Klucel HPC Booklet

8/20/2019 Klucel HPC Booklet

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KlucelKlucel

Klucel ®hydroxypropylcellulose

Klucel

Klucel

KlucelKlucel

KlucelKlucel

Klucel

KlucelPhysicaland Chemical

Properties


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HERCULES INCORPORATEDAq ua lon Divis ionHercules P la za

1313 North Market Street

Wilmington, DE 19894-0001

(302) 594-5000www.aqualon.com

ORDER P LAC EMENT INFORMATION(800) 334-8426

P RODUC T AND TEC HNICAL INFORMATION(800) 345-0447


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KLUCEL® HYDROXYPROPYLCELLULOSE

CONTENTS PAG EKLUCEL® HYDROXYPROPYLCELLULOSE...... 2

APPLICATIONS.................................................. 3

CHEMISTRY ...................................................... 4

GRADES AND VISCOSITY TYPES.................... 5

PROPERTIES...................................................... 6MOISTURE ABS ORPTION .................................. 6

P OLYMER STABILITY........... ............... ............... . 6

BURNOUTTEMP ERATURE ................................ 6

DISPERSION AND DISSOLUTION. . . .. . . .. . . .. . . .. . . . 7IN WATER .............. ............... ............... ............... . 7

Method 1 ........................................................ 7Method 2 ........................................................ 7

Method 3 ........................................................ 7

IN ORGANIC LIQUIDS ........................................ 7IN HOT-MELTS AND WAXES .... ..... ..... ..... ..... ..... . 8

PROPERTIES OF SOLUTIONS. . . .. . . .. . . .. . . .. . . .. . . .. . 9AQUEOUS SOLUTIONS ...................................... 9

Effect of Conc entration and Visc os ity Type .... 9Rheology ........................................................ 10

Effect of Temperature .................................... 10

Precipitation Temperature in Water .............. 11Compa tibility With S urfacta nts...................... 11

Addition of Certain Ionic S urfacta nts ............ 11

Effect of pH .................................................. 11

Effect of Inorga nic Sa lts ................................ 11Compa tibility With Other P olymers .............. 12

Water-So luble Po lymers ............................ 12

Water-Insoluble Po lymers .......................... 13Visc osity S tability .......................................... 13

Hydrolysis and Oxida tion .......................... 13

Biological Sta bility .................................... 13Preservatives ................................................ 13

Surface and Interfacial Tension .................... 14

Recommended Defoamers. . .. . . .. . . .. . . .. . . .. . . .. 14

VISCOS ITY IN ORG ANIC S OLVENTSOLUTIONS .................................................... 15

Visco sity and P recipitation Temp era ture

in Aqueous Alcohols ...................................... 17

THERMOPLASTICITY – MOLDINGAND EXTRUSION .......................................... 18

FORMULATION OF MOLDING

COMPOUNDS .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 18

FILMS AND COATINGS .................................. 19FILM P ROPERTIES............................................ 19

P LASTICIZERS FOR FILMS .............. ............... . 19ADDITIVE AND MOD IFIER FOR FILMS

AND COATINGS .............................................. 19

S OLUTION CASTING FOR FILMS

AND COATINGS .............................................. 19INS OLUBILIZING FILMS AND COATING S .... .... 19

PACKAGING, REGULATORY STATUS,TOXICOLOGY, SAFETY ................................ 20

PACKAGING ...................................................... 20

REGULATORY S TATUS ............... ............... ...... 20

TOXICOLOGY.................................................... 20

PRODUCT SAFETY .......................................... 20

APPENDIX ........................................................ 21METHODS OF ANALYSIS ................................ 21

A. Moisture .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 21B. Viscos ity in Water . . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 21

B . So lution P repa ration .............................. 21

B . Visc os ity Determination ........................ 22

C. Visc osity in Ethanol.................................. 22D. Ash Content . . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 22

PRODUCT LISTING SUP PLEMENT.................. 23

© Hercules Incorporated, 2001.

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KLUCEL® HYDROXYPROPYLCELLULOSE

KLUCEL® hydroxypropylcellulose (HPC) is a nonionic water-so luble c ellulos e e ther with a remarkable co mbination o fproperties . It co mbines organic so lvent s olubility, thermoplas -ticity, a nd s urfac e a ctivity with the aq ueous thickening a ndstabilizing properties characteristic of other water-solublecellulose polymers available from Hercules Incorporated,Aq ualon Division. KLUC EL films a re flexible w ithout plasticiz-ers a nd non-tac ky at high humidity.

The informa tion in this b oo klet prese nts the p hys ica l a ndchemica l properties of KLUCEL as developed in our rese archand plant facilities. Also included is information about thebehavior of KLUCEL with many of the materials that would beused in mos t app lica tions. A guide to regulato ry status a ndtoxico log ica l studies is provided for convenient reference.The Append ix gives informa tion abo ut Aq ualon tes t method sfor visc osity, moisture, a nd a sh c ontent.

To he lp the rea de r ide ntify the versa tile uses for this w a ter-so luble po lymer, a representative listing has been developedand is presented on the following page. Many of these usesfor KLUCEL are discussed in detail in technical literatureava ilab le from your Aq ualon sa les representative by req uest,and /or from o ur webs ite a t ww w.Aq ualon.com.


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Applica tions for KLUCEL® Hydroxypropylcellulose

Types of Uses Specific Applications Properties Utilized

Adhes ives S olvent-ba s ed Thic kenerHot-melt Thermopla s tic

Aerosols Food – w hipped toppings S ta bilizer, foa ming a idEmulsions – c os meticsS olvent-ba s ed Film-former, b inder

B inder B urnout types Rea dy burnout, low res idue,Elec trica l ins ula tors solvent-solubleCeramic glazesAlc ohol core-w a sh compounds Thic kener, b inder s us pend ing agentMa trix boa rd ma nufa c ture S olvent-solub le

C oa tings Edible food c oa tings G la ze, o il- a nd oxygen-ba rrierTextile a nd pa per coa tings S olvent-soluble film-former, oil- a ndFilm coa tings fa t-ba rrier, hea t-s ea la ble

C osmetic s Ha ir s tyling a idsAlc ohol-ba sed prepa ra tions Alc ohol-solub le thickener a nd film-formerPe rfumes a nd colognesEmuls ion c rea ms , lotions , a nd Emuls ion s ta bilizer, thic kenershampoos

Enca psula tion Mic ro- a nd ma croenca ps ula tion S olub le, ed ib le, flexible film ba rrier, fa s t relea se

Extrus ion Film a nd sheet B inder, thermopla s tic , w a ter- a nd

P rofiles a nd fila ment solvent-soluble

Foods Whipped topping s S ta bilizer, w hipping a idEd ib le c oa ting s fo r nuts a nd c and ie s P ro te ctive c oa ting a nd o il b arrie rG la ze for confec tions High g loss a nd c olor coa tingsFa bric a ted foods B inder for mold ing a nd extrus ion

Molding Injec tion-, c ompress ion-, a nd B inder, thermopla s tic , w a ter- a ndb low -molding solvent-soluble

P a int removers Ac id-ba sed Thic kener, a c id res is ta ntS crape -off and flush-off

P a per C oa ting s S olvent-soluble, flexible, thermopla s tic film ba rrier

P ha rma c eutica ls Ta blet b inder Aq ueous a nd solvent solub ilityTa blet coa ting Thermopla s tic b inderModified relea se Non-ionic , pH insens itiveLiq uids a nd semisolids Thic kener, suspending a gent, d iffus ion ba rrier

Flexible films, s urfa ce a ctive

P la s tic foa ms Foa med sheet, tube, rod Thermopla s tic ity

P olyvinyl c hloride S uspens ion polymeriza tion S urfa ce-a c tive protec tive colloidprocessing

P rinting Inks (w a ter-, a lc ohol-, a nd g lyc ol-ba sed) Thic kener, b inder, suspending a gent

Misc ella neous C lea ners (a c id-ba s ed) Thic kener, a c id res is ta ntP o lis hes (a qu eous - a n d s o lvent -b a s ed) Th ic kener, s ta b iliz e r, s us p en d in g a gent

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APPLICATIONS

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CHEMISTRY

KLUCEL® hydroxypropylcellulose is manufactured by reactingalkali cellulose with propylene oxide at elevated temperaturesand pressures. The propylene oxide c an b e s ubstituted o nthe cellulose through an ether linkage at the three reactivehydroxyls present on each anhydroglucose monomer unit ofthe ce llulose cha in. P ublished information sugg ests thatetherifica tion ta kes place in such a wa y that hyd roxypropylsubs tituent groups co ntain almost entirely seco nda ryhydroxyls. The s eco nda ry hydroxyl prese nt in a side cha inis available for further reaction with the oxide, and chaining-out ma y take plac e. This res ults in forma tion of s ide cha inscontaining more than one mole of combined propylene oxide.

It is probab le tha t mos t of the primary hydroxyls o n thecellulose have b een s ubstituted a nd that the reac tive groupsrema ining a re se co nda ry hydroxyls. S ome typica l molecularwe ight values are g iven in Tab le I.

An idealized structure for a portion of a hydroxypropyl-cellulose molecule with a molar substitution (MS) of 3.0 isgiven in Figure 1.

Figure 1Structure of Hydroxypropylcellulose (MS 3.0)


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Ta ble I – KLUCEL Visc os ity Type s, Visc os ities (c ps )(a), a nd Their Corres pond ing Molec ula r Weights

Industrial Grade Concentration in Water by Weight, %

Vis cos ity Types 1 2 5 10 Mw (b)

H Indus tria l 1,275-3,500 – – – 1,150,000M Indus tria l – 3,500-7,500 – – 850,000G Indus tria l – 125- 450 – – 370,000J Indus tria l – – 125-450 – 140,000L Indus tria l – – 65-175 – 95,000E Indus tria l – – – 250-800 80,000

Food Grade, Personal CareGrade, Pharmaceutical Grade


H C S , HF P ha rm 1,500-3,000 – – – 1,150,000M C S , MF P ha rm – 4,000-6,500 – – 850,000G F, G C S , G F P ha rm – 150- 400 – – 370,000J F, J C S , J F P ha rm – – 150-400 – 140,000LF, L C S , LF P ha rm – – 75-150 – 95,000EF, E C S – – – 200-600 80,000EF P ha rm – – – 300-600 80,000

Personal Care Grade,Pharmaceutical Grade

Concentration in Anhydrous Ethanol, by Weight, %


H C S , HF P ha rm 1,000-4,000 – – – 1,150,000M C S , MF P ha rm – 3,000-6,500 – – 850,000G C S , G F P ha rm – 75- 400 – – 370,000J C S , J F P ha rm – – 75-400 – 140,000L C S , LF P ha rm – – 25-150 – 95,000E C S , EF P ha rm – – – 150-700 80,000

Grades of KLUCEL

Intended Market Grade Designation

Indus tria l Indus tria lFood FP ers ona l C a re C SP ha rma ceutic a l F P ha rm

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GRADES AND VISCOSITY TYPES

KLUCEL® hydroxypropylcellulose is produced in severalgrades, determined by intended markets. For each grade,up to six visc osity types a re a vailab le d esignated as H, M,G, J , L, E. P roduct des igna tion is a comb ination of visc ositytype followed by grade designation. For example: Klucel HIndustrial, HF, H C S , a nd HF Pha rm. Tab le I gives the wa terand ethanol visc osity specifica tions b y grad e for eac h ava il-ab le viscos ity type.

(a) All viscosities are determined at 25˚C using a Brookfield LVF viscometer with spindle and speed combinations depending on viscosity level. See Appendix.(b) Weight-avera ge molecular weight determined by size exclusion chromato grap hy.


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POLYMER STABILITY Long-term sto rage sta bility o f KLUCEL hydroxypropylcellulos eis affected by the initial molecular weight of the polymerand storage conditions. Studies have shown that low- andmedium-viscosity types maintain an average of 97% of theiroriginal viscosity after three years when stored at roomtemperature with frequent exposure to the atmosphere.

H visc osity types ha ve a higher molecular weight and,therefore, are mo re s usce ptible to visco sity loss over time.Studies have shown that H viscosity types may sustain upto 10% visc osity loss after one ye ar a nd 20% visc os ity lossafter two years. Storage at room temperatures with infrequentexposure to the a tmosphe re improves viscos ity s tability.Customers are encouraged to retest H viscosity types after

one ye ar a nd q uarterly thereafter to as sure material visc osity.

Ta ble III – Typica l Prope rties for KLUC EL

Product as Shipped

Solubility in water(a) Solutions are clear andsmooth at temperaturesbelow 38˚C.

Solubilit y in organic so lvents Disso lves eas ily in manypolar solvents to giveclear, smooth solutions

B ulk dens ity, g/ml 0.5 (va ries w ith type)S oftening tempera ture 100-150˚CB urnout tempera ture B urns out c ompletely a t

450˚ to 500˚C in N2 or O 2B io lo gic al Oxyg en De ma nd 14,000 ppm

Solutions in WaterSpecific gravity, 2% solution

a t 30˚C 1.010R efra c t ive in dex , 2% so lut io n 1. 337S urfa ce tens ion, a t 0.1% 43.6 d ynes /c mInterfacial tension, 0.1%

KLUC EL in w ate r vs refinedminera l oil 12.5 dynes/cm

Bulking va lue in so lu tion , 0 .04 (0 .334) ga l/lb (l/kg)

(a)Silicon dioxide is added as an anticaking agent and may contribute aslight ha ze.

BURNOUT TEMPERATUREKLUCEL has excellent binding properties. It is often usedas a temporary binder in production of ceramics, glazes,refrac tories, and pow dered meta l produc ts. This polymer isvaporized , or burned out, o ver the temperature rang e o f 250˚to 500˚C in oxidizing, reducing, or inert a tmos pheres. Thevery low as h co ntent of the original KLUCEL and the co m-plete absence of organic residues after firing ensure virtuallyuncontaminated end products after burnout.

All gra de s c onform to the s pec ifications given in Ta ble II.Typic a l prope rties a re g iven in Ta ble III.

Ta ble II – P rod uct S pec ifications for KLUC EL® HP C

Viscos ity Va lues a re show n inTa b le I.

P hys ic a l form White to off-w hite,granular solid

P article s ize (1) min. 85% through 30 meshmin. 99% through 20 meshIndustrial Grad e:min. 80% through 30 meshmin. 98% through 20 mesh

Ash content,ca lculated as Na 2S O4, % 0.2 ma x, s ilic a free

(No ash specification forIndustrial G rades )

Moisture content(a s pa cked), % 5.0 ma x

pH in w a ter solution Food a nd P ersona l C a reGrades: 5.0-8.0Pha rmace utica l Grade:5.0-7.5

Moles of subs titution 3.4 to 4.4

(1)Fine x-grind P harmace utica l Grade E a nd H visco sity types a re availab le a nddesignated as EXAF Pha rm and HXAF Pha rm. Pa rticle size spec ifica tions are:

min. 80% through 100 meshmin. 90% through 80 meshmin. 99.9% through 60 mesh

MOISTURE ABSORPTIONKLUCEL absorbs moisture from the atmosphere, as do otherwa ter-soluble materials. The amo unt abso rbed de pends onrelative humidity and temperature of the environment. Aspacked, moisture content of all grades does not exceed 5% byweight, and is generally between 2% and 3%. It is suggestedthat KLUCEL be s tored in tightly closed co ntainers a nd in adry atmo sphere to prevent any increa se in moisture c ontent.

KLUC EL has a low a ffinity for wa ter. At a ny g iven relativehumidity (RH), it has a low er eq uilibrium mo isture c onte nttha n mos t other wa ter-so luble polymers. Typica l values forKLUCEL are given below.

Eq uilibrium mo isture c ontent a t 50% RHa nd 73˚F (23˚C ) 4%

Eq uilibrium mo isture c ontent a t 84% RHa nd 73˚F (23˚C ) 12%

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PROPERTIES


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KLUCEL® HPC is s oluble in wa ter at room temp erature. Itis insoluble in water above 45˚C. It is readily soluble in manyorganic so lvents, hot or co ld. The be st method s for prepar-ing solutions of KLUCEL in water or organic solvents aredes cribed in the follow ing pa ragraphs .

Note: As a gene ral aid to preparation of s olutions, thefollowing points should be kept in mind:

• Wherever poss ible, KLUCEL should b e put into s olutionbefore a dd ing other soluble ingredients. Other diss olvedmate rials c ompete for the s olvent and slow the s olutionrate of KLUCEL. In this regard, soft water is preferred tohard water for solution preparation.

• KLUCEL is less soluble in hot w ater than in co ld. In orga nicsolvents, applica tion of hea t spee ds the solution rate.

IN WATERMost soluble polymers have a tendency to agglomerate, orlump, when the dry pow der is first wet with solvent. Hydra-tion of the outer surfac e of a particle, or an ag glomerate ofparticles (lump), results in the formation of a viscous gel layertha t inhibits w etting of the inside ma terials. The fa ste r the rateof hydration of the polymer, the more quickly the gel layer willbe developed, and the greater the tendency for lumping asthe dry powder is added to the solvent.

KLUCEL hydrates some wha t slowly, and lumping c an b eavoided during s olution preparation if the recommend ed

proc edures a re follow ed. Lump formation sho uld b e a voided ,as this c an g rea tly increas e the time req uired to preparehomogeneous solutions.

To prepa re lump-free , clea r so lutions of KLUCEL in theshortest time, the following methods are suggested.

Method 1The preferred me thod involves p re-slurrying the po wd er in anonsolvent, such a s hot w ater or g lycerin, prior to a dd ition tothe main volume of water.

In the first step, prepare a high-solids slurry by adding dryKLUCEL powder to 6 times (or more) its weight of well-ag itated hot w ate r at a temperature o f 50˚ to 60˚C. Tempera-

ture s hould not exc eed the 60˚C maximum indicated . The hotslurry must be ma intained a bove 50˚C during this preso ak toensure that there is no premature dissolving of the particlesthat w ould res ult in the formation of a g elatinous ma ss . Theslurry should be allow ed to s tir for a few minutes b eforead dition to the ma in volume o f co ld wa ter. This preso akresults in a fas ter diss olving o f particles in the sec ond s tep.

DISPERSION AND DISSOLUTION

In the sec ond s tep, the hot s lurry is d iluted w ith cold w ater(room tempe rature or low er). Agitation is c ontinued until allparticles a re d iss olved and solution is c ompletely free ofgels. High-shear agitation is not necessary, and may beundesirable because of the tendency for foaming and airentrainment. In this dissolving step, the time factor is moreimportant than high shea r when it comes to ens uringcomplete solution of all gel particles.

Dissolving periods of 10 minutes or more may be required,depending on solution concentration and viscosity type beingused . S olutions of lower-visc os ity KLUCEL types at low -solids co ncentration req uire the s hortest time for preparation.

Method 2Add pow dered KLUCEL to the vortex of well-agitated wa terat room temperature. The rate o f ad dition must be slow enough to pe rmit pa rticles to sepa rate in the w ater. Add itionof the powder should be completed, however, before anyap preciab le visco sity buildup is ob ta ined in the s olution. Therate of a gitation then ma y be reduc ed, but co ntinued until age l-free so lution is o bta ined. Throug hout the m ixing period ,solution temp erature s hould be maintained below 35˚C.

Method 3Dry-blend KLUCEL w ith any inert or nonpo lymeric so lublematerial that will be used in the formulation. Blending aidssepa ration o f pa rticles of KLUCEL at first we tting andreduc es the tende ncy to lump. For best results, KLUCELsho uld b e less than 20% of the tota l dry blend . This blend

is then handled as described in Method 2.

IN ORGANIC LIQUIDSAll types of KLUCEL have exc ellent s olubility in a w ide rang eof polar organic liq uids and give clear, smo oth so lutions atamb ient or elevated temperatures. There is no tendenc y forprecipitation o f KLUC EL in hot orga nic so lvents ; this is incontras t to its b ehavior in w ater s olutions. Ge nerally, themore polar the liquid, the better the solution. Methyl andethyl alco hol, propylene glycol, dioxane, and Celloso lve a resome of the be st orga nic s olvents for all types o f KLUCEL.

Ta ble VIII, pa ge 15, lists the typ e o f so lutions o bta ined w ithG visc osity types in ma ny orga nic liq uids . The mo lecularweight of the type of KLUCEL can ha ve a m arked effect on

solution quality in an organic liquid that is a borderline solventfor KLUCEL.


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G viscosity types are intermediate in viscosity (i.e., molecularwe ight) betw een high H visc osity types a nd very low Evisc osity types. In compa riso n with G viscos ity types, lowe r-visc osity types a re more rea dily so luble a nd ma y give betterso lutions . The higher-visc os ity type s m ay give s lightlyinferior solutions in some of the liquids listed in the table.For example, ac etone g ives e xcellent so lutions with theE visc osity types, but a ceto ne so lutions o f the G viscos itytypes a re ha zy and somew hat granular.

Solution quality in borderline solvents often can be greatlyimproved through the use o f sma ll quantities of co solvents.Water, metha nol, a nd e thanol function as excellent c oso l-vents a nd, in many c as es, are effective in relatively sm allq uantities (5% to 15%). For exa mple, me thylene c hlorideis a borderline s olvent for high H visc osity types, andsolutions are granular. Addition to the system of 10%methanol results in a smooth solution of normal viscosity(5,000 cps a t 1% solids).

Elevated temperatures will improve solvent power of organicliq uids for KLUCEL® HPC, and there is no tendency forprecipitation of the po lymer at thes e elevated temperatures.Heating of solvents will (a) reduce viscosity, (b) increase rateof solution, and (c) improve solution quality in the case ofborderline solvents.

Aliphatic and aromatic hydrocarbons and petroleum distil-lates are no nso lvents for KLUCEL. How ever, relatively largequantities of these nonsolvents can be tolerated in a solution

if KLUCEL is first diss olved in a so lvent tha t is misc ible w iththese nonsolvents. Examples of s olvent-nonsolvent s ystemsa re given in Ta ble VIII. Figure 2 deta ils the e ffect of s olventcomposition on viscosity of a solution of G Industrial in atoluene:ethanol sys tem.

In g eneral, principles discuss ed for prepa ring wa ter solu-tions apply when us ing o rga nic s olvents to make s olutionsof KLUCEL. Methods 1, 2, and 3 des cribed for prepa ringwa ter solutions c an therefore be used to prepare solutionsof KLUCEL in orga nic s olvents. The “ pre-slurry” principle ofMethod 1 ca n be em ployed through the use o f nonsolventssuch as glycerin, aliphatics, aromatics, and others.

In aqueous-organic systems, the proportion of organicsolvent will determine whether elevated temperature willspeed or slow the rate of solution of KLUCEL. (See Viscositya nd P recipitation Temp erature in Aq ueo us Alcoho ls, pa ge 17).

IN HOT-MELTS AND WAXESAt elevated tem peratures, many w axes are sufficiently go odsolvents so that KLUCEL is rea dily d iss olved by a dd ition ofthe dry pow der to the s tirred molten wa x. Examples ofmaterials that a re g ood solvents for KLUCEL at a n elevatedtemperature are: acetylated monoglycerides (e.g., Myvacet5-00 a nd 7-00 s eries ); g lyc eride s (e.g ., Myverol 18-07);polyethylene glycols (e.g., C arbow ax); po lypropylene g lyco l,pine oil, and tall oil fatty acids.

KLUCEL is compatible with a number of high-molecular-weight, high-boiling waxes and oils, and can be used tomod ify the properties o f these m a teria ls. The a dd ition ofKLUCEL to these sys tems will increas e viscos ity andimprove hardness and crack resistance to coatings.

Figure 2Viscosity of G Industrial Dissolved in Toluene-Ethanol

5,000

1,000

500

100

G Industrial, at 2%

KLUCEL S olubleKLUCELInsoluble


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KLUCEL® HPC has excellent so lubility in water a nd in manypolar orga nic s olvents, a s d isc usse d in the Dispersion a ndDiss olution s ec tion s tarting o n pa ge 7. S olutions are c lea r,smo oth, and exceptionally free from gels a nd fibers.S olutions are non-Newto nian in flow, s ince they cha ngein viscosity with rate of shear. But solutions display littleor no thixotropy.

Be ca use KLUCEL is use d e xtensively to mo dify visc osity ofsolutions, dispersions, emulsions, and suspe nsions involvingwa ter and/or orga nic s olvents, a discuss ion of so me of thefac tors that a ffect solution viscos ity follow s.

PROPERTIES OF SOLUTIONS

AQUEOUS SOLUTIONSAt room temperature, solutions of KLUCEL can be preparedin a wide range of viscosities, depending on concentrationand visc os ity type used . Since s olutions a re non-New tonian,it is essential to standardize viscosity determination methods.The metho d us ed in the co ntrol labo ratory a t Aq ualon isdescribed in detail in the Appendix.

Effect of Concentration and Viscosity TypeThe visco sity of s olutions of KLUCEL increa se s ra pidly withconc entration and bec omes almost a straight-line relation-ship whe n plotted o n a s emi-log ba sis. (S ee Figure 3.) Theba nds in this figure indicate the visc osity range within w hichea ch type is s upplied. (S ee a lso Tab le I, pag e 5.)

Figure 3Effect of Concentration and Type of KLUCEL on Viscosity of Water Solutions

100,000

10,000

1,000

100

10

0 2 4 6 8 10 12 14

B r o o k f i e l d V i s c o s i t y a t 2 5 ˚ C ,

c p s ( m P a s )

S olids Co ncentration o f KLUCEL, wt%

H ViscosityTypes

M ViscosityTypes

G ViscosityTypes

J ViscosityTypes

L ViscosityTypes

E ViscosityTypes


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H Visc os ity Typ e,at 1%

10

RheologyS olutions of KLUCEL are exceptionally s mooth-flow ing andexhibit little or no structure o r thixotropy. How ever, so lutionsare pseudoplastic under conditions of high rates of shearand will show a tem porary dec rea se in visc os ity while undershe a r. The visc os ity returns to the o riginal value w hen theshe a r is remo ved . The lowe r the molecular weight ofKLUCEL and the lower the she ar rate, the less will bethis d ecreas e in visc os ity experience d under shea r.

Effect of TemperatureVisc osity of an a q ueous s olution of KLUCEL decreas es a stempe rature is increa se d. This effect is norma l for polymersin solution. This cha nge in visco sity is illustrate d in Figure 4for H visc osity type and J visc osity type. As s hown, viscos ityis halved a s te mpe rature is raise d through 15˚C. This e ffect isuniform up to the p rec ipitation tem perature (40˚ to 45˚C).

Figure 4Effect of Temperature on the Viscosity of Aqueous Solutions of KLUCEL

Temperature, ˚C

V i s c o s i t y ,

c p s ( m P a s )

10,000

1,000

1000 5 10 20 30 40 50 60 70

Cooling

P recipita tion Temperature

Heating

KLUCELPrecipitates

J Visc osity type,at 5%


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Precipitation Temperature in WaterAs a lrea dy s tated , KLUCEL® HPC will precipitate from w aterso lution at a temp erature be twe en 40˚ and 45˚C. This prec ipi-ta tion is c omp letely reversible. The po lymer red isso lves uponco oling the sys tem be low 40˚C with stirring, a nd the originalvisc osity is restored.

As the temperature reaches 40˚ to 45˚C, this precipitationphenomenon is evidenced by appearance of cloudiness inthe aq ueous s olution a nd b y a marked reduction in visc os ity.These effects a re due to sep aration of the polymer as a highlysw ollen prec ipitate . The trans ition from d isso lved to prec ipi-tated polymer takes plac e w ithout the formation of a gel. Theonly apparent viscosity change is one of a rapid decrease, asshown in Figure 4.

The form in w hich KLUCEL prec ipitate s from a q ueoussolutions d epend s not o nly on the mo lecular weight of thepolymer, but also on other materials present in solution andwhether or not stirring is employed. Low-visc osity types tendto se parate as highly sw ollen a nd finely divided precipitates .High-viscosity types, particularly under agitation, mayag glomerate on hea ting a nd form a s tringy, rather than afinely divide d, precipita te. The a dd ition o f Aq ualon® cellulosegum or surfactants reduces the tendency for agglomerationof the KLUCEL polymer as it precipitates , a nd by this me ans ,the high-visc osity types a lso c an b e se parated in finelydivided form.

The prec ipita tion te mpera ture o f KLUCEL is increas ed

through the ad dition of o rga nic liq uids that a re s olventsfor the polymer. The prec ipitation te mpera ture in aq ueousalcohols and aqueous glycol is discussed in another section.

The prec ipita tion te mpera ture is lowe r in the prese nce ofrelatively high concentrations of other dissolved materialsthat co mpete for the wa ter in the system . The ma gnitude o fthe low ering is dep endent on the na ture a nd c once ntration ofthe other d isso lved ingredients. The d ata in Tab le IV illustra tethis effect.

Tab le IV – Co mpa rative Effect o f S olutionCo mpo sition o n P recipitation Tempe rature

Ingredients and Precipitation

Concentration Temperature, ̊C

1% H visc os ity type 411% H visc os ity type + 1.0% Na Cl 381% H visc os ity type + 5.0% Na Cl 300.5% H vis cos ity type + 10% S uc ros e 410.5% H vis cos ity type + 20% S uc ros e 360.5% H vis cos ity type + 30% S uc ros e 320.5% H vis cos ity type + 40% S uc ros e 200.5% H visc os ity type + 50% S ucrose 7

11

Compatibility With SurfactantsCompatibility of KLUCEL with surface-active agents will varyaccording to the particular agent and concentration, as wellas to the grade and concentration of KLUCEL used.

Because of its hydroxypropyl substitution, KLUCEL is morelipophilic in nature than other w a ter-so luble c ellulos e d eriva-tives. Accordingly, it is compatible with a wide range ofanionic, no nionic, ca tionic, and amp hoteric s urfac tants.

Addition of Certain Ionic SurfactantsS tudies with KLUCEL using certain ionic surfacta nts ha veaided the de velopment of tec hnolog y to permit thickening a ttemperatures in exces s o f the normal cloudpoints for KLUCEL.Aqueous solutions of M viscosity type and sodium laurylsulfate, at a surfac tant to KLUCEL ratio o f 1:3 or greater,result in cloudpoints in excess of 70˚C. At some ratios,cloudpoints greater than 95˚C may be achieved.

Included in these studies were the following ionic surfactants,which proved to be effective:

• Sodium lauryl sulfa tes• Ammonium lauryl sulfates• Lauryl alcohol ether sulfate• Trimethylco co ammo nium chloride

The nonionic surfac ta nts s tudied w ere not effective in raisingthe c loudpoints.

Effect of pHKLUCEL HPC is a nonionic polymer, a nd viscos ity of w atersolutions is not a ffec ted b y cha nges in pH. The visc osity ofsolutions remains unchang ed a s pH is varied o ver the rangeof 2 to 11.

However, where long-term storage stability is required,the solution pH is an important cons ideration bec aus e ofdeg rada tion that c an o cc ur under highly ac id o r alkalinecond itions, as des cribed in the s ec tion titled Visc osityS tability, pa ge 13.

Effect of Inorganic SaltsThe c omp a tibility of KLUC EL w ith diss olved inorga nic s a ltsin water solution varies according to the salt. If relatively high

concentrations of dissolved salts are used, there is a ten-denc y for the KLUCEL polymer to be “s alted o ut” fromsolution as a finely divided and highly swollen precipitate.

This s alting-out phenom enon g enera lly results in so medecrease in viscosity and in the appearance of cloudiness inthe so lution. In borderline c as es, this sa lting o ut may not beimmediately apparent, but may occur upon standing.


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The c omp atibility of G visc os ity types with a numbe r ofse lect ed sa lts is illustra ted in Ta ble V.

Ta ble V – C ompa tibility of KLUCEL® HPC With So meInorganic S alts (a)

Salt Salt Concentration,% by weight

2 5 10 50

Aluminum sulfa te C I – –Ammonium nitra te C C C IAmmonium sulfa te C I – –

Ca lc ium chloride C C C IDisodium phospha te I – – –Ferric c hloride C C C IP ota ss ium ferroc ya nide C C I –S ilver nitra te C C C IS odium a c eta te C C I –S odium c a rbona te C I – –S odium c hloride C C I –S odium nitra te C C C IS odium sulfa te C I – –S odium sulfite C I – –S odium thiosulfa te C I – –S uc rose C C C I

Key: C = compa tible; I = incompa tible(a)

Tests were conducted by a dding a 2% solution of G visco sity type to sa lt

solutions o f various conc entrations. The sa lt co ncentration in the system isindicated, and the final concentration of KLUCEL was approximately 0.1%by weight in all cases .

Compatibility With Other PolymersKLUCEL has a wide rang e o f co mpatibility with orga nicma terials. The d ual s olubility o f KLUC EL permits its a dm ix-ture with water-soluble, as well as solvent-soluble, resins,polymers, a nd o rga nic liq uids .

In spite of this wide compatibility, the KLUCEL polymer, whenused in aq ueous systems, may not tolerate high concentra-tions of other d iss olved ma terials. The b alanc e o f hydrophilic-lipophilic properties of the polymer, w hich a re req uired fordual solubility, reduces its ability to remain hydrated in thepresence of high concentrations of other dissolved materials.

KLUCEL may precipitate or “salt out” under these conditions.

A detailed discussion of compatibility with natural andsynthetic p olymers a nd inorga nic s alts follow s.

12

Water-Soluble Polymers

KLUCEL is c ompa tible with most na tural gums and syntheticwater-soluble polymers. Solutions in water are homogeneous,and films ca st from thes e s olutions are uniform. The follow inghave been tested a nd found to be compa tible:

• AQUALON® sod ium ca rboxymethylcellulose (CMC)• NATROSOL® hydroxye thylcellulos e (HEC)• B ENEC EL® methylce llulos e (MC)• S UP ERC OL® guar gum• G ela tin• So d ium c a s e in a te• Polyethylene oxide• C a rb o wa x 1000• Polyvinyl a lcohol• So d ium a lg in a te• Lo c us t be a n g um

The effec t on so lution visco sity of blends of KLUCEL andother water-soluble polymers varies, depending on the ionicnature o f the c opo lyme r. To illustrate , b lend s of KLUCEL withNATROS OL hydroxyethylcellulos e a nd C MC w ere stud ied.The blends we re prepared a t a 1:1 ratio of the two polymers.The res ults o f this s tudy a re g iven in Ta ble VI.

Solution viscosity of blends of nonionic polymers KLUCELand NATROS OL wa s e ss entially in agree ment w ith theca lculated value. This wa s true for all visc os ity types studied.

When solutions of blends of KLUCEL and an ionic polymer,

CMC, w ere prepa red, the resultant visc osity wa s g rea terthan the ca lculated value. The s ynergism o f this co mbinationincrease d with increas ing mo lecular weight of the polymers.

The d a ta s how n in Ta ble VI were ob tained w ith so lutionsprepa red in distilled wa ter or ta pw a ter. The sy nergistic effectmay b e dras tica lly reduc ed in the prese nce o f low levels ofdissolved sa lts or if pH is b elow 3 and ab ove 10.


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Ta ble VI – B lends of KLUC EL® HPC and Other Water-Soluble Polymers: Effect on Viscosity

Polymer Blend (1:1) Concentration, % Solution Viscosity, cps (mPas)

Viscosity Types Expected Initial After 24 Hours

J a nd NATROS OL® 250J HEC 5 235 240 235M a nd NATROS OL 250M 2 6,250 5,900 5,600H a nd NATROS OL 250H 1 2,320 2,440 2,440H and AQUALON® C MC -7H 1 2,220 4,400 3,860

13

Water-Insoluble Polymers

KLUCEL is com patible w ith ma ny natural and synthetic

latexes available as emulsions in water. KLUCEL is solublein the aqueous phase, and uniform films and coatings areobtained upon drying.

Using co mmon so lvents, KLUCEL has be en incorporatedwith wa ter-insoluble po lymers s uch a s zein, shellac ,AQUALON ethylcellulose, and cellulose acetate phthalate.Films and coatings prepared from these systems are homo-geneous a nd of goo d q uality.

Viscosity StabilityWater s olutions of KLUCEL posse ss bes t viscos ity s tab ilitywhen pH is held between 6.0 and 8.0, and when the solutionsare protected from light, hea t, and ac tion of microorga nisms .

KLUC EL in w ate r solution, like other w a ter-so luble polyme rs,is susceptible to both chemical and biological degradation.This deg rad a tion g enera lly res ults in red uction of molecularwe ight of the disso lved polymer, with an ac co mpanyingdec rea se in visc os ity of the so lution. S ome los s o f solutionclarity may occur in cases of severe biological degradation.

KLUCEL has demonstrated greater resistance to chemicaland biological degradation than other cellulose ethers.Techniques to minimize deg rada tion me cha nisms arediscussed in the following two sections.

Hydrolysis and Oxidation

KLUCEL in solution is susceptible to acid hydrolysis, whichcauses chain scission and loss of viscosity of the solution.The rate of hyd rolysis increase s with temperature a nd

hydrogen ion co ncentration. S olutions s hould b e buffered topH 6.0 to 8.0 a nd maintained at low temperature to minimizeac id hydrolysis.

Alkali-cata lyzed oxida tive d egrad ation w ill also d egrad e thepolymer a nd result in de crea se in visc os ity of s olution. Thedegradation can result from presence of dissolved oxygenor oxidizing a ge nts in the s olution. P eroxides and sod iumhypochlorite under alkaline c onditions c aus e rapid de grad a-tion. For best s tab ility on s torage , pH should be maintainedbetween 6.0 and 8.0 and antioxidants should be used ifoxidative degradation is likely to occur.

Ultraviolet light will degrade the cellulose, and solutions ofKLUCEL will undergo s ome dec rea se in visc osity if expose d

to light for several months.

Biolog ical Stability

The high level of s ubs titution o f KLUC EL improves resista nceof this po lymer to deg rada tion by c ellulas e enzymes pro-duced by molds and bacteria. However, water solutions aresusceptible to degradation under severe condtions, and avisc osity dec rea se m ay result. If prolonged storag e is con-templated, a preservative is recommended.

Certain enzymes, produce d b y microbial action, will deg radeKLUCEL in so lution. If microbial co nta mination is prese nt inmakeup water, it is important that sterilization techniqueseffective against enzymes as well as against microorganismsbe employed prior to preparing the solution of KLUCEL.

Solutions of KLUCEL in organic solvents do not generallyrequire preservative.

PreservativesListed below are so me o f the prese rvatives that a re effectivein preserving solutions of KLUCEL. It is recommended thatthe preservative ma nufac turer be co nsulted reg arding kind,amount, and rate of use for the preservative to be added.

• Dow icil 100 n-(3-chloroa llyl)-hexam inium chloride• Fo rma ldehyde• P henol• Oma dine

Some of the preservatives that are effective with KLUCEL and

are in complianc e w ith the Food and Drug Administration foruse in food a re listed below.

• S o d ium b enz oa te• So rbic ac id and its potassium, sodium, and ca lcium salts• Sodium propiona te• Methyl and propyl parahydroxybenzoate

Note: S olutions o f KLUCEL have dem onstrated someincomp atibility w ith a number of prese rvatives ba sed onsubs tituted phenol d erivatives.


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Ta ble VII – Surfac e a nd Inte rfac ial Tens ions of KLUCELSolutions at 25˚C

Surface Interfacial TensionTension, vs Refined Mineral Oil,

dynes/cm dynes/cmKLUCEL, wt% (mN/m) (mN/M)

0 (w a ter) 74.1 31.60.01 45.0 –0.1 43.6 12.50.2 43.0 –

14

Surface and Interfacial TensionKLUCEL® HPC is a surface-active polymer. Water solutionsdisplay greatly reduc ed surfac e a nd interfac ial tension.Be ca use o f this, KLUCEL functions a s a n aid in both emulsi-fying and whipping. These properties , c oupled w ith protectivecolloid action, enable it to perform dual functions in thefollowing systems:

• Oil-in-Water Emulsions – S tab ilizer a nd emulsifica tion a id

• Foamed Systems – Stabilizer and w hipping a id

The reduc tion in surfac e a nd interfac ial tens ion of wa terso lutions c ont a ining KLUCEL is illust rate d in Ta ble VII. Allviscosity types have essentially the same effects, and aconcentration of KLUCEL as low as 0.01% produces closeto the maximum reduc tion in surfac e tens ion.

Recommended Defoamers

The low surfac e te nsion of w ater s olutions co ntainingKLUCEL tends to promote foaming a nd air entrainment. Ifthis prese nts a difficulty, a wa ter-dispersible a ntifoam ag entca n be used a nd should be ad ded to the water prior tosolution preparation.

Water-dispersible de foame rs s uch a s HERCULES ® 1512defoamer; Colloid 581-B; Nopco NDW and KFS; AntifoamAF; or lauryl or octyl alcohol are effective. De foame d conc en-trations g enerally run 25 to 200 ppm, but it is s ugg ested thatthe ma nufacturers be cons ulted for their rec ommend ations

for the particular system involved.


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VISCOSITY IN ORGANIC SOLVENT SOLUTIONSThe visc os ity-vs-co nce ntration curve for KLUC EL® HPCdisso lved in orga nic liq uids , which a re g ood solvents for thepolymer, show s the s ame ge neral pattern as that for KLUCELdiss olved in wa ter (Figure 3, pa ge 9). The visc os ity rise srapidly as the c once ntration of po lymer is increase d. Thecurves for visc osity in ethanol and methanol pa rallel thosefor viscosity in water, but are displaced toward somewhatlow er visc osity values.

Ta ble VIII – S olvents for KLUC EL(a)

A. CLEAR AND SMOOTH

Ac etic ac id (g la cia l) Isopropyl a lcohol (95%)Ac etone:w a ter (9:1) Metha nolB enze ne:me tha no l (1:1) Methyl C ello so lveC elloso lve Methylene c hloride:

metha nol (9:1)C hloroform MorpholineC yc lohexa none M-P ryolDimethyl forma mide P ropylene g lycolDimethyl sulfoxide P yridineDioxa ne t-B uta nol:w a ter (9:1)Ethyl a lc ohol Tetra hydrofura nEthyle ne c hlo ro hyd rin To lue ne :e tha no l (3:2)Formic a c id (88%) Wa terGlycerin:water (3:7)

B . MODER ATELY G RANULAR AND/OR HAZY

Ac etone Methyl a c eta teB utyl a c eta te Methyl ethyl ketoneB utyl C ellosolve Methylene c hlorideC yc lohexa nol Na phtha :etha nol (1:1)Is opro pyl a lc oho l (99%) Te rtia ry buta no lLa ctic a c id Xylene:isopropyl a lc ohol

(1:3)

C. INSOLUBLE

Alipha tic hyd ro ca rb ons Methyl c hlo ro fo rmB enzene Minera l oilsC a rbon tetra c hloride S oybea n oilDichlorobenzene Toluene

Kerosene G a solineTric hloroethylene G lyc erinXylene Linseed oil

(a) Solvents were tested using G viscosity types at 2% solids concentration byweight. All ratios indicated in this table are on a by-weight basis.

15


18/26

Ta ble IX – Co mpa rative Visco sity of KLUCEL in Wa ter and Ce rtain Orga nic S olvents

Solvent Viscosity(a) Type of KLUCEL and Concentration,cps (mPas)

H at 1% G at 2% L at 9% E at 10%

Wa ter 2,100 270 80 275Metha nol 800 85 25 75Metha nol:w a ter (3:7 by w eight) – 360 – –

Etha nol 1,600 210 65 255Etha nol:w a ter (3:7) – 500 – –

Isopropyl alcohol (99%) (b) (b) 145 570Isopropyl a lc ohol (95%) – – 130 420

Acetone (b) (b) 50 175Methylene c hloride 4,500 (b) – 1,240 (b) 14,600 (b)

Methylene c hloride:metha nol (9:1) 5,000 – 400 –

Chloroform – – 2,560(B)

17,000 (b)

P ropylene g lyc ol 6,000 6,640 5,020 >10,000Ethylene c hlorohydrin 470 430 310 1,110

(a) Viscosities shown are presented only as typical values. Some variation in these viscosities will be obtained from lot to lot of each type of KLUCEL.(b) Borderline solvent for the particular type of KLUCEL. Solutions are granular and may be hazy.

16

Where orga nic liq uids that are b orderline s olvents forKLUCEL® HPC are used, unusual viscosity effects can beobserved. Viscosity may be abnormally high or abnormallylow, depending on the degree of solvation of the polymer. Forexa mple, a s sho wn in Tab le IX, H visco sity types in me thylenechloride ga ve a p oo r solution w ith red uced visc os ity. The Lvisc osity types, which was better solvated, g ave a solutionwith unusually high viscosity. In both cases, the addition of asmall amount of a cosolvent (10% methanol) gave solutionswith normal viscosities.

Ta ble IX list s typ ica l so lution visc os ities for various type s o fKLUCEL in a number of s olvents.


19/2617

Viscosity and Precipitation Temperature inAqueous AlcoholsThe visc os ity o f so lutions of KLUCEL® HPC in aq ueousa lco hols varies with comp os ition of the so lvent. The visc os itygo es through a m aximum value at a so lvent compo sition of7 parts w ate r: 3 pa rts alco hol by we ig ht. This is illustrate din Figure 5. This type o f visc os ity curve is o bta ined whe nKLUCEL is a dd ed directly to a q ueous a lcoho l or when it isfirst dissolved in either wa ter or alcohol with subseq uentaddition of the second solvent.

Addition of alcohol to a water solution of KLUCEL willincreas e the temperature a t w hich the polymer will precipitatefrom s olution. Temp erature elevation is de pend ent on typ eand co ncentration of a lco hol. The effect ob tained w ithmethanol and ethanol is detailed in Figure 6. As shown,so lutions o f KLUC EL conta ining 45% (by volume) of etha nolor methanol ca n be heated to the bo iling po int of the so lutionwithout prec ipita tion o f KLUCEL.

P ropylene g lyco l performs s imilarly to methanol, a nd eleva-tion of precipitation temperature falls on the same curve.Other water-miscible organic liquids, which are good solventsfor KLUC EL, w ill also func tion to elevate precipita tiontemperature o f the polymer in the s ystem.

Figure 5Viscosity of Aqueous Alcohol Solutions (G viscosity typesat 2% concentration by weight)

Boiling Points

Ethanol-Water

Methano l-Wa ter

Alcohol Content, % by volume

P r e c i p i t a t i o n T e m p e r a t u r e ,

˚ C

Figure 6Precipitation Temperature of KLUCEL in Aqueous Alcohols

1,000

100

100 20 40 60 80 100

Water Content of Aqueous AlcoholS olvent, % by weight

Ethano l-Wa ter

Methanol-Water

V i s c o s i t y ,

c p s ( m P a s )


20/2618

KLUCEL® HPC is an excellent thermoplastic polymer that canbe proc ess ed by virtually a ll fab rica tion method s use d forplastics. Injection- a nd co mpress ion-molding; blow-molding;injection foam molding; vacuum-forming; and extrusion offilm, shee t, foam profiles, and filame nt have be en de mon-strated on c onventiona l plas tics eq uipment, using pelletizedmolding po wd er.

All molecular weight types are thermoplas tic and ca n berea dily mo lded and extruded . In general, the low-molecular-weight types are preferred in injection- and blow-molding,where rigidity, hardness, and dimensional stab ility a re m ostimportant. The me dium- to high-molecular-weight ty pes a rerecommended for most extrusion systems where greaterflexibility and higher tens ile p roperties are d es ired . Whenfillers or extenders are used, the higher-molecular-weighttypes of KLUCEL are selected for their superior bindingproperties and their ability to maintain good flexibility andtoughness, even at filler levels up to 90% by weight.

FORMULATION OF MOLDING COMPOUNDSWhile not essential, small amounts of plasticizers are normallyused with KLUCEL to ensure smooth, uniform melt flow andhomog eneous end produc ts. The a dd ition of plas ticizers willgive finished articles softer a nd more flexible c harac teristics.P las ticizers such as propylene g lyco l, g lyce rin, polyethyleneglycols, and trimethylolpropane are generally suitable.

Internal lubrica nts a re a dd ed to KLUCEL molding po wd ers toprovide lubrication at the die wall or mold wall, ensuring easy

release from m old surfaces and preventing lam ination of theKLUCEL to itself, as in a roll of KLUC EL hydroxypropyl-cellulose film. Glycerol monostearate, silicones, lecithin,and various stearates have proved useful.

Antioxida nts a lso c an b e a dd ed to the low -molec ular-we ighttypes to prevent discoloration and thermal degradation.Butylated hydroxytoluene, lauryl thiodipropionate, andascorbic acid are a few of the effective antioxidantscommonly used .

Fillers, extenders, and compatible polymers may be added toKLUCEL to impart some functional property, to vary physicalcha racteristics, o r to reduc e c osts . In general, any fillermaterial that will withstand the melt temperatures of KLUCELca n be incorporated and proces sed as with other plas tics.Numerous filler materials, s uch a s sta rch, ta lc, dete rge nts,frag rances , pigments, fertilizers, various foo d produc ts, a ndsome drugs and medicinals, have been successfully evalu-ated in molding a nd extrusion systems . Depending on theparticle size and bulk density of the filler, loadings of 40 to95 weight % are possible with KLUCEL.

A twin-sc rew extruder is recommend ed for the preparation o fpelletized molding pow ders. A single-screw extruder ca n beused if it is e q uipped with a nylon screw or metering s crew having a long, d eep-flighted feed s ection.

Most a rticles fa brica ted from KLUCEL are c ustom-formulate dto o bta in the d esired physical properties and solubility ratereq uired for a s pec ific applica tion. We s ugg est that youcontact your Aqualon sales representative for assistancein formulating a prod uct to me et your needs .

THERMOPLASTICITY – MOLDING AND EXTRUSION


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The e xc ellent film prop erties o f KLUC EL® HPC make it auseful material for fabrication of film and sheet. It is alsouseful in the formulation of c oa tings on pa per, fab rics , foodprod ucts, a nd other substrates . Flexible pac kaging films a ndsheet can be produced with conventional extrusion tech-niques. Coatings can be applied by extrusion or fromaq ueous or orga nic solvent systems.

FILM PROPERTIESAll films of KLUCEL are c ha rac terized by the fo llowingoutsta nding properties:

• Excellent flexibility• Lac k of tac kiness at high humidity• Good hea t sea lab ilit y• Barrier to oil and fa t

PLASTICIZERS FOR FILMSSince films of KLUCEL® HP C a re inherently flexible, it isnot nece ss ary to a dd plas ticizers to ca st films. How ever, inextruded films, plasticizers provide desirable die lubrication,reduction in melt visc os ity, a nd improveme nt in melt uni-formity. In a ll films of KLUCEL, ad de d plas ticizer w ill softenthe film, reduce heat-sea l temperatures, and impart improvedflexibilty and increased elongation. Plasticizer levels of 5% orless (usually 2% or less) are recommended. Higher additionlevels lea d to reduced tensile properties, increase d ta ckinessat high humidity, and poorer clarity, dimensional stability, andsolubility characteristics.

The fo llowing p la sticizers a re c omp a tible in films of KLUCELat a conc entration of 5%:• P ro py lene g lyc ol• G lyc erin• Trimethylolpropane• Polyethylene glycols

For improved resistance to tackiness at high humidity, thefollow ing lubrica nts a re recom mende d:• P olyethylene glycols (1,000 to 20,000 molec ular weight)• Propylene glycol monostearate• G lycero l monos teara te• S ilic one

ADDITIVE AND MODIFIER FOR FILMS AND COATINGSThe g oo d film properties a nd w ide rang e of s olubility ofKLUCEL make it a useful additive and modifier for other filmsand coatings. Solubility in polar organic solvents permitsaddition to many organic-solvent-soluble resins, while abroad range of co mpa tibility ensures homog eneous filmsof improved quality.

The a dd ition of KLUC EL in co a tings ge nerally:• Improves flexibility.• Improves toughness .• Improves heat-seal properties.• Reduces wa ter res is t ance .• Reduces the tendency to crack .

SOLUTION CASTING FOR FILMS AND COATINGSThe s olubility of KLUCEL in w ate r as we ll as in po lar orga nicsolvents a ffords a wide c hoice in the preparation of so lutionsused for cas ting film or for coa ting operations.

KLUCEL is insoluble in hot water, so care must be exercisedwhen drying a queous coa tings to a void the “ blushing” thatca n occ ur at high temperatures a nd that might impa ir thefilm properties.

INSOLUBILIZING FILMS AND COATINGSFilms a nd c oa tings of KLUCEL can b e ma de insolublethrough crosslinking with resins that are reactive with theavailable hydroxyl groups on the KLUCEL polymer. A numberof resins are capable of performing this crosslinking reaction.

Rate of c ure a nd e xtent of insolubility of the final co mpos itionare g enerally d epend ent not o nly on the reactivity of theinsolubilizing resin, but also on the temperature of the cure,pH of the sys tem, a nd the a mount of cross linking resin used.High temperature, low pH, and higher proportions of resinstend to increa se the rate o f cure, improve w ater resistanc e,and increase stiffness.

The crosslinked c ompos ition ma y poss ess a high deg ree ofinsolubility in water, but the composition is not completelyresista nt and ge nerally sw ells in the pres enc e of w a ter. Thismeans that films a nd c oatings have reduced w et strengthand lose toughness.

FILMS AND COATINGS


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PACKAGINGKLUCEL® HPC is shipped in fiber drums with a polyethyleneinner liner containing 100 lbs net.

REGULATORY STATUSFood g rad e, de signated with a “F,” c omplies w ith the re-quirements of the US FDA for direct addition to food forhuman cons umption, as spec ified in the C ode of FederalReg ulations, Title 21, S ec tion 172.870. Food gra de Klucelalso conforms to the specifications for hydroxypropylcellulosese t forth in the Food Chemicals Codex .

Personal Care grade, de signated with “C S,” conforms to thesp ec ifica tions fo r hydroxypropylcellulos e s et forth in the C TFA.

Pharmaceutical grade, designated with “F Pharm,” conformsto the spe cifica tions for hydroxypropylce llulos e s et forth in theU.S. National Formulary, European Pharmacopoeia and theJapanese Pharmacop oeia .

TOXICOLOGY Toxicity tes ting indica tes tha t KLUCEL is p hys iolog ica lly inert.The results of repeat-insult pa tch tes ts o n humans discloseno e vide nce tha t it is either a primary s kin irritant or skin-sens itizing a gent. Feed ing o f KLUCEL to rats for 90 da ys a tdietary levels up to a nd including 5.0% produc ed no g ross orhistopathologic changes or other deleterious effects. KLUCELis co nside red nutritionally eq uivalent to purified ce llulos e inthat neither material is meta bolized . For a co mplete report,reque st a co py o f B ulletin T-122, “KLUCEL® Hydroxypropyl-

ce llulose: S umma ry of Toxicolog ica l Inves tiga tions .”

PRODUCT SAFETY KLUCEL is a flamma ble dust when finely d ivided andsuspe nded in a ir. An explosion c an oc cur if the sus pende ddust is ignited. P roper de sign and operation of facilities andgood housekeeping practices can minimize this hazard.

Floors s ubjec t to spills or dusting w ith KLUCEL ca n be co meslippery when w etted with wa ter. Follow go od housekeepingpractices and clean up spills promptly.

Read and understand the Material Sa fety Data S heet (MSDS)before using this product.

CAS RN: 9004-64-2CAS Na me: C ellulose 2-hydroxypropyl ether

PACKAGING,REGULATORY STATUS,TOXICOLOGY, SAFETY


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The s olution volumes s pec ified unde r item 4 s hould not beless than outlined or there may not be sufficient solution tocover the appropriate Brookfield spindle.

1. Weigh the specified amo unts to ± 0.005 g, as o btainedfrom Ta ble XIII, pa ge 24, q uickly into c lean, g round-glas s-stoppe red weighing bottles. Sto pper immed iately toeliminate ga in or loss of mo isture c ontent.

2. From the determined percent moisture, ca lculate thewater to be added for the respective viscosity solutions,as follows :

a. For a 1% visco sity solution:

(Weight o f KLUCEL, g )

x (99 – % mo isture) = Weigh t of w a ter, g

b. For a 2% visc osity solution:

(Weight o f KLUCEL, g )x (98 – % moisture)

= Weight of wa ter, g2

c. For a 5% visco sity solution:

(Weight o f KLUCEL, g )x (95 – % moisture)

= Weight of w ate r, g5

d. For a 10% visc osity solution:(Weight o f KLUCEL, g )

x (90 – % moisture)= Weight of w ate r, g

10

3. Add the ca lculated a mount of distilled w ater to a16-oz bo ttle.

4. Stir the wa ter with a mechanical ag itator to c reate avortex, and slowly s ift the KLUCEL into the vortex over a15 to 30-sec period to ens ure g ood dispersion. An a nchor-shaped stirrer turned by a compressed-air or electricmotor has been found to be satisfactory. After the solutionappears to be complete, stir it for an additional 10 to 15min at high speed. Be careful to avoid loss of solution.

5. When the solution is complete, cover the mouth of thebottle w ith cellophane a nd s crew the c ap on se curely.P lac e it in a cons tant-temperature b ath (25˚ ± 0.2˚C) for30 min, or for as long as neces sa ry to ad just the so lutiontemperature to 25˚ ± 0.2˚C.

METHODS OF ANALYSISAll types of KLUCEL® HPC meet certain specifications formoisture, viscos ity, a nd a sh c ontent. Detailed des criptionsare g iven of Aq ualon methods for determining thes e va lues.

A. Moisture1. Weigh d uplica te sa mples o f 5 g, to the nea rest 0.001 g, into

previously dried and we ighed moisture c ans with covers.2. Place the sa mples in a gravity convection oven main-

tained a t 105˚ ± 0.5˚C. Heat for 3 hrs. C ool in a desicca torand w eigh.

3. Return the sa mple to the oven for 45 min. Cool and w eighas before. If the se co nd d ried we ight is not w ithin 0.005 gof the first dried weight, repeat the 45-min oven periodsuntil two s ubseq uent weighings are in ag reement. Then,using the lowest dried weight obtained, calculate percentmoisture a s follow s:

Originalsample weight – dry sample weight

x 100 = % moistureOriginal sample weight

B. Viscosity in WaterAs e xplained on pa ge 9, the appa rent visc osity of a so lutionof KLUCEL depend s o n a number of fac tors. If reproducibleresults are to be obtained, a closely standardized methodof s olution prepa ration a nd visc osity de termination mustbe followed.

Preparation of the solution is critical in that KLUCEL must becompletely dissolved in order to obtain a significant measure-ment. In weighing out the proper amount of KLUCEL for avisc osity determination, ca re must be taken to include amoisture correction. This correction com pens a tes for themoisture in KLUCEL and plac es the visc osity mea surementof KLUCEL on a dry ba sis. The viscos ity-mea surement testmust be rigidly standardized because the viscosity readingobtained is dependent on the rate of shear during dissolution,the am ount of ag itation prior to mea surement, the tempera-ture, and the elapsed time between agitation and measure-ment. The metho d use d in Aq ualon labo ratories is thereforegiven here in detail.

Solut ion Preparat ion

Immediately after taking portions of the KLUCEL polymersa mple for mo isture d etermination, portions of the sa meundried KLUCEL should be taken for viscosity solutionprepa ration. Weighings o f moisture and so lution sa mplesshould be ca rried out practically tog ether to ensure that themoisture c ontent of the respec tive portions is the s ame attime o f we ighings.

The s tand ardized Aqualon method for determining theviscosity of solutions of KLUCEL specifies use of theBrookfield viscometer, Model LVF (Brookfield EngineeringLabs , S toughton, Massa chusetts; 4 spindles, 4 spee dscovering the range 0 to 100,000 cps).

21

APPENDIX


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C. Viscosity in EthanolThe visco sity of etha nol so lutions of KLUCEL is d eterminedin the sa me ma nner as for aq ueous s olutions, b ut with thefollowing modification:

1. To minimize e vaporation of the ethano l, the bottle may becapped and mechanically shaken to accomplish solutionof the KLUCEL instead of stirring the solution by hand.

2. Repeat steps 5, 6, 7, 8, and 9 a s d esc ribed in the Visco sityin Water procedures.

D. Ash ContentThe a sh c ompone nts of KLUCEL are s odium sa lts. Dete rmi-nation of these is complicated by the presence of certainanticaking a ge nts, w hich c ontribute to the to tal as h. The a sh

method is referenced in the National Formulary , c urrent ed ition.

22

Viscosi ty Determ inat ion

6. While the s olution is in the co nstant-temperature b ath,se lec t from Tab le XIII below the B rookfield s pindle-sp eedcom bination c orrespo nding to the viscos ity type ofKLUCEL® HPC being tested. Determine the viscosity ofthe KLUCEL within 2 hrs after removing it from the stirrer.If the solution stands longer than 2 hrs, return it to thestirrer for 10 min, place it in a bath for 30 min, and thendetermine viscosity.

7. Remove the bottle from the c onstant-temperature ba thand stir the solution by hand for 10 sec, using a stirringrod. Avoid shaking or vigorous stirring, as this will increaseair bubbles, which interfere with viscosity measurement.

8. Immed iately insert the appropriate B rookfield visc ometerspindle into the solution and start the spindle rotating.Allow it to rotate for 3 min before taking the reading.

9. S top the instrument and read the dial. Multiply the dialreading by the factor corresponding to the speed andspindle use d. The result is the visc os ity of the so lutionin centipoises.

Ta ble XIII – Sa mple Weights of KLUCEL, and Broo kfield S pindle and S pee d fo r Visc os ity Mea surement

ViscosityConcentration, % Sample Wt, g

Brookfield Settings

rpm Spindle No.

E 10 25.0 30 2L 5 11.0 30 1J 5 11.0 60 2G 2 5.2 60 2M 2 5.2 60 4H 1 2.3 30 3

Type


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PRODUCT LISTING SUPPLEMENT

23

The follow ing list o f produc ts, a long w ith their che mica l ide ntityand source of supply, may be helpful to the reader who isunfamilia r with some of the p roducts referred to in this boo klet.

Read and understand the Material Safety Data Sheets(MSDSs) before using these products.

Product Chemical Identity Manufacturer

Antifoam AF Dimethylpolys iloxa ne ma teria ls S tew art Ha ll Chemica l

Aqualon® CMC S odium ca rboxymethylcellulose Hercules Incorpora ted

Benecel® MC Methylcellulose Hercules Incorpora ted

Butyl C ellosolve Ethylene g lycol monobutyl ether-solvent Dow Chemica l C o.

Ca rbow ax 1000 P olyethylene g lycol Dow Chemica l C o.

Cellosolve Ethylene g lycol monoethyl ether-solvent Dow Chemica l C o.

C ollo id 581-B Hy dro ca rb on-b a se d m ate ria l c o nta ining s urfa c ta nts , w a xe s, and me ta llic s oa ps Rhô ne -P o ule nc , Inc .

Defoa mer 1512 S ilica -type defoa mer Hercules Incorpora ted

Methyl Cellosolve Ethylene g lycol monomethyl ether Dow Chemica l C o.

M-P yrol N-methyl-2-pyrrolidone G AF Corpora tion

Myvacet Acetyla ted monog lyceride Eas tma n C hemica l P roducts , Inc.

Myverol Monoglyceride Eas tma n C hemica l P roducts , Inc .

Natrosol® HEC Hydroxyethylcellulose Hercules Incorpora ted

No pc o KFS P ro prie ta ry ble nd o f hyd ro ca rb on oil, fa tty a cid s, wa x, a nd no nio nic s urfa cta nts He nke l C orpo ra tio n

Nop co NDW P rop rie ta ry b lend o f h yd rocarb on o ils , s ilicone , non ionic su rfac tan ts , an d meta llic soap s Henke l C orp ora t ion

Oma dine S odium 1-hydroxpyridine-2-thione Olin Chemica ls


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The produc ts a nd related information provided by Hercules a re for manufacturing use only. Hercules m akes no express , implied, o r other represen-tation, warranty, or guarantee concerning (i) the handling, use, or application of such products, whether alone, in combination with other products, or

otherwise , (ii) the co mpleteness , definitivenes s, o r adeq uac y of suc h information for user’s or other purpos es, (iii) the q uality of suc h products , exce pt

that such products are of Hercules’ standard quality. Users are advised to make their own tests to determine the safety and suitability of each product

or product c ombination for their own purposes Read and understand the Material Sa fety Data Sheets (MSDSs ) before using these products

Documents

Klucel HPC Booklet