Chapter 10 Carbon: More Than Just Another Element

John C. Kotz • State University of New York, College at Oneonta

John C. KotzPaul M. TreichelJohn Townsend

http://academic.cengage.com/kotz

Chapter 10Carbon: More Than Just Another Element

22

© 2009 Brooks/Cole - Cengage

Important – Read Before Using Slides in Class

Instructor: This PowerPoint presentation contains photos and figures from the text, as well as selected animations and videos. For animations and videos to run properly, we recommend that you run this PowerPoint presentation from the PowerLecture disc inserted in your computer. Also, for the mathematical symbols to display properly, you must install the supplied font called “Symb_chm,” supplied as a cross-platform TrueType font in the “Font_for_Lectures” folder in the "Media" folder on this disc.

If you prefer to customize the presentation or run it without the PowerLecture disc inserted, the animations and videos will only run properly if you also copy the associated animation and video files for each chapter onto your computer. Follow these steps:

1. Go to the disc drive directory containing the PowerLecture disc, and then to the “Media” folder, and then to the

“PowerPoint_Lectures” folder. 2. In the “PowerPoint_Lectures” folder, copy the entire chapter

folder to your computer. Chapter folders are named “chapter1”, “chapter2”, etc. Each chapter folder contains the PowerPoint Lecture file as well as the animation and video files.

For assistance with installing the fonts or copying the animations and video files, please visit our Technical Support at http://academic.cengage.com/support or call (800) 423-0563. Thank you.

33


ORGANIC CHEMISTRYORGANIC CHEMISTRYORGANIC CHEMISTRYORGANIC CHEMISTRY

44


cinnamaldehyde

eugenol

55


Types of Organic Types of Organic CompoundsCompounds

• Vast majority of over 20 million known compounds are based on C: organic compounds.organic compounds.

• Generally contain C and H + other elements

• Great variety of compounds

66


IsomerismIsomerism• Isomers Isomers have identical composition have identical composition but different structuresbut different structures

• Two forms of isomerismTwo forms of isomerism– Constitutional (or structural)Constitutional (or structural)– StereoisomerismStereoisomerism

• ConstitutionalConstitutional– Same empirical formula but different Same empirical formula but different atom-to-atom connectionsatom-to-atom connections

• StereoisomerismStereoisomerism– Same atom-to-atom connections but Same atom-to-atom connections but different arrangement in space.different arrangement in space.

77


Structural IsomersStructural Isomers

88


Cis-2-buteneCis-2-butene

Stereoisomers: Stereoisomers: GeometricGeometric

Geometric isomers can occur when there is a C=C double bond.

Trans-2-buteneTrans-2-butene

99


• Optical isomersOptical isomers are molecules are molecules with non-superimposable mirror with non-superimposable mirror images.images.

• Such molecules are called Such molecules are called CHIRALCHIRAL• Pairs of chiral molecules are Pairs of chiral molecules are enantiomersenantiomers..

• Chiral molecules in solution can Chiral molecules in solution can rotate the plane of plane rotate the plane of plane polarized light.polarized light.

Stereoisomers: Stereoisomers: OpticalOptical

1010


Chiral Compounds—Polarized Chiral Compounds—Polarized LightLight

1111


Stereoisomers Stereoisomers IsomersIsomers

Chirality Chirality generally generally occurs when occurs when a C atom has a C atom has 4 different 4 different groups groups attached.attached.Lactic acid

1212


Stereoisomers Stereoisomers IsomersIsomers

Lactic acid isomers Lactic acid isomers are are nonsuperimposablenonsuperimposable

1313


Chirality: Chirality: Handedness in NatureHandedness in Nature

These molecules are non-These molecules are non-superimposable mirror superimposable mirror

images.images.

1414


Chirality: Chirality: Handedness in NatureHandedness in Nature

These amino acids are non-superimposable These amino acids are non-superimposable mirror images.mirror images.

1515


Stereoisomers in Stereoisomers in NatureNature

Right- and Right- and left-handed left-handed seashellsseashells The DNA here The DNA here

is right-is right-handedhanded

1616


The egg cases of The egg cases of the whelk have a the whelk have a right-handed right-handed twist.twist.

1717


• Compounds of C and HCompounds of C and H• Subgroups: Subgroups: –Alkanes: C-C single bondsAlkanes: C-C single bonds–Alkenes: C=C double bondsAlkenes: C=C double bonds–Alkynes: carbon-carbon Alkynes: carbon-carbon triple bondstriple bonds

–Aromatic: based on benzeneAromatic: based on benzene

HydrocarbonsHydrocarbons

1818


• Alkanes have the general Alkanes have the general formula Cformula CnnHH2n+22n+2

• CHCH44 = methane = methane

• CC22HH66 = ethane = ethane

• CC33HH88 = propane = propane

• CC44HH10 10 = butane= butane

• CC55HH1212 = pentane = pentane

HydrocarbonsHydrocarbons

1919


2020


Methane Hydrate, CHMethane Hydrate, CH44(H(H22O)O)xx

2121


Pentane

2-Methylbutane

2,2-Dimethylpropane

CH3CH2CH2CH2CH3

CH3CHCH2CH3

CH3

H3CCCH3

CH3

CH3

Hydrocarbons Hydrocarbons & Structural & Structural IsomerismIsomerism

CC55HH1212 has 3 has 3 structural structural isomers.isomers.

CC66HH1414 has 5 has 5


CC55HH1212 has 3 has 3 structural structural isomers.isomers.



Isomers of CIsomers of C55HH1212??Isomers of CIsomers of C55HH1212??

Note names of isomersNote names of isomersNote names of isomersNote names of isomers

2222


Alkanes are colorless Alkanes are colorless gases, liquids, and solidsgases, liquids, and solids

Generally unreactive (but Generally unreactive (but undergo combustion)undergo combustion)

Not polar (or low polarity) Not polar (or low polarity) and so are not soluble in and so are not soluble in water.water.

Hydrocarbons: Hydrocarbons: AlkanesAlkanes

2323


All compounds are flexible. All compounds are flexible.

Cyclohexane, CCyclohexane, C66HH1212, has interconverting , has interconverting “chair” and “boat” forms.“chair” and “boat” forms.

Hydrocarbons: Hydrocarbons: CycloalkanesCycloalkanes

Axial H atom

Equatorial H atom

Chair form Boat form

123

56

1

23

44

5 6

H H

H

H

H

H

H

H

H

H

H

H

HH

H

H

H

H

H

H

H

H

H

H

H

H

H

H

HH

H

H

H

H

H

Chair form

1

6

2

34

5

H

2424


Alkenes: Compounds Alkenes: Compounds with C=C Double Bondswith C=C Double Bonds

• How many isomers are possible for How many isomers are possible for a compound with the formula Ca compound with the formula C44HH88??

CH3

CC

H

CH3H

H

CC

H

CH3H3C

H

CC

H3C

CH3H

2-methylpropene(isobutene)

cis-2-butene trans-2-butene

H

CC

H

CH2CH3H

1-butene

1 2

3 4

1

1

1

2

3

2 23 3

4 4

CH3

CC

H

CH3H

H

CC

H

CH3H3C

H

CC

H3C

CH3H

2-methylpropene(isobutene)

cis-2-butene trans-2-butene

H

CC

H

CH2CH3H

1-butene

1 2

3 4

1

1

1

2

3

2 23 3

4 4

2525


Alkenes—Alkenes—Many Occur NaturallyMany Occur Naturally

2626


Reactions of Alkenes:Reactions of Alkenes:ADDITION REACTIONSADDITION REACTIONS

• Alkenes are Alkenes are unsaturated unsaturated — more — more bonds can form to the C atomsbonds can form to the C atoms

• Molecules such as BrMolecules such as Br22, H, H22, HCl, , HCl,

HBr, and HHBr, and H22O O addadd to the double bond to the double bond

C CCH

H

H

HC

Br BrH H

HH

+ Br2

1,2-dibromoethane

C CCH

H

H

HC

Br BrH H

HH

+ Br2

1,2-dibromoethane

2727


An Addition ReactionAn Addition Reaction

• The fat in bacon is partially The fat in bacon is partially unsaturated. The fat adds Brunsaturated. The fat adds Br22 to to the C=C bonds.the C=C bonds.

• Fats can be “hydrogenated” with HFats can be “hydrogenated” with H22..

Fat Fat placed in placed in BrBr22 vapor vapor

2828


An Addition ReactionAn Addition Reaction

Fat Fat placed in placed in BrBr22 vapor vapor

PLAY MOVIE

2929


An Addition ReactionAn Addition Reaction• Fats can be “hydrogenated” with HFats can be “hydrogenated” with H22..

Peanut butter has partially Peanut butter has partially hydrogenated vegetable oil.hydrogenated vegetable oil.

Peanut butter has partially Peanut butter has partially hydrogenated vegetable oil.hydrogenated vegetable oil.

PLAY MOVIE

3030


Trans Fatty Acids

tend to raise total blood cholesterol

CHCH33(CH(CH22))77CH=CH(CHCH=CH(CH22))77COCO22H H

3131


Trans Fatty AcidsTrans Fatty AcidsFood Percentages of Trans-Fatty Acids

Butter 3.6

Soft Margarine 5.2

Hard Margarine 12.4

Vegetable Oils, Including Safflower, Sunflower, and Soy

0

Beef burger, Fried or Grilled

0.8

Chocolate Cake with Icing 7.1

3232


AlkynesAlkynes

• Alkynes have carbon-carbon triple bonds. Alkynes have carbon-carbon triple bonds.

• CC22HH22: common name = acetylene: common name = acetylenesystematic name = ethynesystematic name = ethyne

Preparation:Preparation:

CaCCaC22(s) + H(s) + H22O(liq) --O(liq) --

> >

C C22HH22 (g) + (g) +

Ca(OH)Ca(OH)22(s)(s)∆∆ffHHoo(C(C22HH22, g) = +226.7 , g) = +226.7 kJ/molkJ/mol

Preparation:Preparation:

CaCCaC22(s) + H(s) + H22O(liq) --O(liq) --

> >

C C22HH22 (g) + (g) +

Ca(OH)Ca(OH)22(s)(s)∆∆ffHHoo(C(C22HH22, g) = +226.7 , g) = +226.7 kJ/molkJ/mol

∆∆rrH for CH for C22HH22 + O + O22 = –1300 kJ/mol= –1300 kJ/mol

∆∆rrH for CH for C22HH22 + O + O22 = –1300 kJ/mol= –1300 kJ/mol

3333


Aromatic CompoundsAromatic Compounds

• Benzene, CBenzene, C66HH66, in , in the top 25 the top 25 chemicals chemicals produced in the produced in the U.S. U.S.

• Starting point Starting point for hundreds of for hundreds of other compounds.other compounds.

3434


Resonance in BenzeneResonance in Benzene

• CC66HH66 has two resonance structures with has two resonance structures with alternating double bonds. alternating double bonds.

• The π electrons are The π electrons are delocalizeddelocalized over the ring. over the ring.

CC

CC

C

CC

C

CC

C

C

H

H

HH

H H

H

H

HH

H H

CC

CC

C

C

H

H

HH

H H

Resonance structures of benzene, C6H6 Abbreviated representation of resonance structures

3535


Resonance in BenzeneResonance in Benzene

• CC bond order is _______________CC bond order is _______________• C–C single bond = 154 pm C–C single bond = 154 pm C=C bond = 134 pmC=C bond = 134 pm

• CC bonds in benzene = 139 pmCC bonds in benzene = 139 pm

π electrons delocalizedπ electrons delocalized

3636


Bonding in BenzeneBonding in Benzene

3737


Other Aromatic Other Aromatic HydrocarbonsHydrocarbons

TolueneToluene NaphthaleneNaphthalene

3838


Benzene DerivativesBenzene Derivatives

AnilineAnilineCC66HH55NHNH22

PhenolPhenol

CC66HH55OHOH

TNTTNTtrinitrotoluenetrinitrotoluene

CC66HH44CHCH33(NO(NO22))33

3939


Naming Benzene Naming Benzene DerivativesDerivatives

1,4-dimethylbenzeneCommon name: Para-xylene

Cl

Ortho to Cl

Meta to Cl

Para to Cl

12

3

4

5

6

4040


Reactions of AromaticsReactions of Aromatics• SubstitutionsSubstitutions — not additions — are typical.

+ CH3Cl

CH3

+ HClAlCl3

AlClAlCl33 is a catalyst. Catalysts is a catalyst. Catalysts typically used in aromatic typically used in aromatic

substitutions.substitutions.

4141


Functional GroupsFunctional Groups

See Chemistry Now, Chapter 10See Chemistry Now, Chapter 10See Chemistry Now, Chapter 10See Chemistry Now, Chapter 10

4242


AlcoholsAlcohols• Characterized by –OH groupCharacterized by –OH group• Name: add –ol to name of Name: add –ol to name of hydrocarbonhydrocarbon

MethanolMethanol

ButanolButanol

4343


Structures of AlcoholsStructures of Alcohols

CC33HH55OH: how many structural isomers?OH: how many structural isomers?

C C C OH

H

H

H

H

H

H

H

1-propanol

C C C H

H

H

OH

H

H

H

H

2-propanol

Naming:Naming: Add -ol to name of 3-C hydrocarbon. Add -ol to name of 3-C hydrocarbon. Indicate position of OH with number.Indicate position of OH with number.

4444


Alcohol PropertiesAlcohol Properties• Alcohols are a derivative of water Alcohols are a derivative of water • Many alcohols dissolve in waterMany alcohols dissolve in water

Methanol Methanol dissolves in dissolves in water.water.

Methanol Methanol dissolves in dissolves in water.water.

Butanol is NOT Butanol is NOT soluble in water. soluble in water.

Butanol is NOT Butanol is NOT soluble in water. soluble in water.

4545


““Sterno”Sterno”

• Alcohols burn in Alcohols burn in

air air

• A mixture of A mixture of

ethanol + calcium ethanol + calcium

acetate = STERNOacetate = STERNO

4646


GLYCOLSGLYCOLSAlcohols with Two OH Alcohols with Two OH

GroupsGroups

EthyleEthylene ne glycolglycol

4747


Alcohol ReactionsAlcohol ReactionsScreen 11.6Screen 11.6

SubstitutionSubstitution Elimination—Elimination—the reverse the reverse of of additionaddition

PLAY MOVIEPLAY MOVIE

4848


TYPES OF ALCOHOLSTYPES OF ALCOHOLS

R C OH

H

H

R C OH

R

H

R C OH

R

R

CH3CH2OH, ethanol

rubbing alcohol H3C C OH

CH3

H

Primary

Secondary

Tertiary

4949


More Alcohol ReactionsMore Alcohol Reactions

Ethanol is a Ethanol is a PRIMARY PRIMARY ALCOHOLALCOHOL. It is . It is oxidized to an oxidized to an ALDEHYDE and then to ALDEHYDE and then to an ACID.an ACID.

C

C

C

H H

H OH

HH

(l)

C

H O

H OH

H

(l)

Ethanol

+ Oxidizing agent

Acetic acid

+ Oxidizing agentC C

H O

H H

H

(l)

Acetaldehyde

5050


More Alcohol ReactionsMore Alcohol Reactions

SECONDARY ALCOHOLS SECONDARY ALCOHOLS are oxidized are oxidized to KETONES — and reaction stops to KETONES — and reaction stops there. there.

R—C—R'

oxidizing agent

R—C—R'

O

Secondary alcohol KetoneH

(–R and –R' are organic groups. They may be the same or different.)

OH

5151


Sugars: Related to Sugars: Related to AlcoholsAlcohols

• Sugars are carbohydrates, compounds Sugars are carbohydrates, compounds with the formula Cwith the formula Cxx(H(H22O)O)yy..

What is the difference between What is the difference between and and D-glucose?D-glucose?

What is the difference between What is the difference between and and D-glucose?D-glucose?

O

H

HO

H

HO

HOHH

OH

OHCHO

OHH

HHO

OHH

OHH

CH2OH

O

H

HO

H

HO

OHOHH

H

OH

1

23

4 5

12

3

45

1

2

3

4

5

-D-glucose β-D-glucose

Open chain form

H H

5252


Sucrose and RiboseSucrose and Ribose

O

CH2OH

CH2OHH

HOOH

H

H

O

H

HO

H

HO

H

OOHH

H

OH

-D-Glucose

Fructose

O

HOH

HHHH

HOOHO

HOH

HHHH

HOOH

DeoxyriboseDeoxyribose, the sugar , the sugar in the DNA in the DNA backbone.backbone.

5353


AminesAminesAminesAminesAlcohols are derivatives of HAlcohols are derivatives of H22O O (R–OH) and (R–OH) and aminesamines are are derivatives of NHderivatives of NH33..

MethylamineMethylamine DimethylamineDimethylamine TrimethylamineTrimethylamine

5454


AminesAminesAminesAminesAmines generally have terrible

odors!

CadaverineCadaverine

PyridinePyridine

5555


AminesAminesAminesAminesAmines, like NHAmines, like NH33, are bases, are bases

2 C6H5NH2(aq) + H2SO4(aq) 2 C6H5NH3+(aq) + SO4

2-(aq)

Aniline Anilinium ion

5656


AminesAminesAminesAmines

Many natural Many natural products products and drugs and drugs (such as (such as nicotine nicotine and and cocaine) cocaine) are bases.are bases.

NicotineNicotineHH++

5757


Compounds with Compounds with Carbonyl GroupCarbonyl Group

AldehydeAldehydeAldehydeAldehyde Carboxylic acidCarboxylic acidCarboxylic acidCarboxylic acid KetoneKetoneKetoneKetone

C

O

5858


Structures of Structures of AldehydesAldehydes

CinnamaldehydeCinnamaldehyde Odors from aldehydes Odors from aldehydes and ketonesand ketones

5959


Carboxylic AcidsCarboxylic AcidsBenzoic Benzoic acidacid

Carboxylic acid Carboxylic acid group with group with acidic Hacidic H++

All are All are WEAKWEAK acids acids

Acetic acidAcetic acid

Acids are Acids are found in many found in many natural natural substances: substances: bread, fruits, bread, fruits, milk, winemilk, wine

Acids are Acids are found in many found in many natural natural substances: substances: bread, fruits, bread, fruits, milk, winemilk, wine

6060


Carboxylic Carboxylic AcidsAcids

C

OC

O O

H

O

CH3

Aspirin, acetylsalicylic acidAspirin, acetylsalicylic acid

Formic acid, Formic acid, HCOHCO22H, gives H, gives the sting to the sting to

ants.ants.

Formic acid, Formic acid, HCOHCO22H, gives H, gives the sting to the sting to

ants.ants.

6161


Acids + Alcohols --> Acids + Alcohols --> ESTERSESTERS

Esters have generally pleasant odorsEsters have generally pleasant odors

6262



One of the important reactions in nature!One of the important reactions in nature!

H+

O O

CH3COH + CH3CH2OH CH 3COCH2CH3 + H 2O

Acetic acid Ethanol Ethyl acetate

O

RC—O—HH+

O

+ R'—O—H RC—O—R' + H2O

Carboxylic acid Alcohol Ester

6363



Acetic acid

OC CH2CH2CHCH3

O

H3C

CH3

3-methylbutanol

3-methylbutylacetate

Many fruits such as Many fruits such as bananas and bananas and strawberries strawberries contain esters.contain esters.

6464


GlycerolGlycerolAlcohol with 3 OH GroupsAlcohol with 3 OH Groups

Combine this with long chain acids Combine this with long chain acids ff ??? ???Fatty acids Fatty acids ff fats and oils fats and oils

Combine this with long chain acids Combine this with long chain acids ff ??? ???Fatty acids Fatty acids ff fats and oils fats and oils

6565


Fats and OilsFats and Oils

R = organic R = organic group with group with NONO C=C bondsC=C bondsCC1212 = Lauric = Lauric acidacidCC1616 = Palmitic = Palmitic acidacidCC1818 = Stearic = Stearic acid acid

R = organic R = organic group with group with NONO C=C bondsC=C bondsCC1212 = Lauric = Lauric acidacidCC1616 = Palmitic = Palmitic acidacidCC1818 = Stearic = Stearic acid acid

O

O

O

H2C

HC

H2C

CRO

CRO

CR

O

R = organic R = organic group group WITHWITH C=C C=C

bondsbondsCC1818 = oleic = oleic

acidacid

R = organic R = organic group group WITHWITH C=C C=C

bondsbondsCC1818 = oleic = oleic

acidacid

What is the What is the functional functional

groupgroup in a fat in a fat or oil?or oil?

What is the What is the functional functional

groupgroup in a fat in a fat or oil?or oil?

6666


Fats and OilsFats and OilsO

O

O

H2C

HC

H2C

CRO

CRO

CR

O

Fats with C=C bonds are Fats with C=C bonds are usually LIQUDSusually LIQUDS

Fats with C=C bonds are Fats with C=C bonds are usually LIQUDSusually LIQUDS

Oleic acid: a Oleic acid: a monounsaturatmonounsaturated fatty acid ed fatty acid

Oleic acid: a Oleic acid: a monounsaturatmonounsaturated fatty acid ed fatty acid

C=C bondC=C bondC=C bondC=C bond

6767


Fats and OilsFats and Oils

Fats with saturated acids (no Fats with saturated acids (no C=C bonds) are SOLIDS.C=C bonds) are SOLIDS.

Fats with saturated acids (no Fats with saturated acids (no C=C bonds) are SOLIDS.C=C bonds) are SOLIDS.

O

O

O

H2C

HC

H2C

CRO

CRO

CR

O

Saturated fats Saturated fats are more common are more common in animals. in animals.

Saturated fats Saturated fats are more common are more common in animals. in animals.

6868


Fats and Polar BearsFats and Polar Bears•Bears gorge on Bears gorge on blubber in the blubber in the winter.winter.

•During the summer During the summer bears rely on bears rely on stored fat for stored fat for energy.energy.

•Burn 1-1.5 kg of Burn 1-1.5 kg of fat per day.fat per day.

•Water for Water for metabolism comes metabolism comes from fat burning.from fat burning.

•Bears gorge on Bears gorge on blubber in the blubber in the winter.winter.

•During the summer During the summer bears rely on bears rely on stored fat for stored fat for energy.energy.

•Burn 1-1.5 kg of Burn 1-1.5 kg of fat per day.fat per day.

•Water for Water for metabolism comes metabolism comes from fat burning.from fat burning.

6969


Trans Fatty AcidsTrans Fatty Acids•Oleic acid is a mono–Oleic acid is a mono–unsaturated unsaturated cis-cis-fatty acidfatty acid

•Trans fatty acids have Trans fatty acids have deleterious health effects. deleterious health effects.

•Trans fatty acids raise Trans fatty acids raise plasma LDL cholesterol and plasma LDL cholesterol and lower HDL levels.lower HDL levels.

C=C bondC=C bondC=C bondC=C bond

7070


Fats and Oils: Fats and Oils: SaponificationSaponification

OCH2

CH

CH2

O—HO—H

O—H

Glycerol

+ 3 RC—O- Na +

Sodium stearate, a soap

OO CR

OO CR

CH2

CH

CH2

OO CR

Glyceryl stearate, a fat + NaOH

R = —(CH2)16CH3

+ 3 NaOH

7171


Acids + Amines --> Acids + Amines --> AMIDESAMIDES

N-methylacetamideN-methylacetamide

7272


Acids + Amines --> Acids + Amines --> AMIDESAMIDESC

C

C

C

C

C

H

H

N

H

O

HCC

O

H

HH

H

H

Amide link

AcetaminophenAcetaminophenTylenol, Datril, Momentum, ...Tylenol, Datril, Momentum, ...AcetaminophenAcetaminophenTylenol, Datril, Momentum, ...Tylenol, Datril, Momentum, ...

7373


Alpha-Amino AcidsAlpha-Amino Acids

H

CH3C CO2

NH3

Chiral -carbon

Alanine

C

H

H2N C

O

OH

RAcidAmine

7474


Peptides and ProteinsPeptides and Proteins

H3NO–

O

HHOCH2H3NO–

O

CH3H

NO–

O

CH3H

H

H3N

O

HHOCH2

peptide bondSerineAlanine

+

Adding more peptide links ---> PROTEINAdding more peptide links ---> PROTEIN

– H2O

7575


PolymersPolymersPolymersPolymers

• Giant molecules made by Giant molecules made by joining many small molecules joining many small molecules called called monomersmonomers

• Average production is 150 kg Average production is 150 kg per person annually in the per person annually in the U.S.U.S.

7676


Polymer Polymer ClassificationsClassifications

• ThermoplasticsThermoplastics (polyethylene) (polyethylene) soften and flow when heatedsoften and flow when heated

• ThermosettingThermosetting plastics — soft plastics — soft initially but set to solid initially but set to solid when heated. Cannot be when heated. Cannot be resoftened.resoftened.

• Other classification: Other classification: plastics, fibers, elastomers, plastics, fibers, elastomers, coatings, adhesivescoatings, adhesives

7777


Polymer PreparationPolymer Preparation

• AdditionAddition polymers — polymers — directly adding monomer directly adding monomer units togetherunits together

• CondensationCondensation polymers — polymers — combining monomer units combining monomer units and splitting out a small and splitting out a small water (water)water (water)

7878


Polyethylene: Addition Polyethylene: Addition PolymerPolymer

H2C CH2 C C

H

H

H

H

n

n

EthyleneEthylene PolyethylenePolyethylene

A polymer with a molar A polymer with a molar mass of 1emass of 1e66 has about has about 360,000 units.360,000 units.

7979


Mechanism of Addition Mechanism of Addition PolymerizationPolymerization

PLAY MOVIE

8080


Types of PolyethyleneTypes of Polyethylene

Linear, high density Linear, high density PE (HDPE)PE (HDPE)

Branched, low Branched, low density PE, LDPEdensity PE, LDPE

Cross-linked PE, Cross-linked PE, CLPECLPE

8181


Types of PolyethyleneTypes of Polyethylene

CH2CH

OH

CH2CH

OCCH3

CH2CH

n n n

polyvinyl alcohol polyvinyl acetate polystyrene

Polymers based on Substituted Ethylenes, CH2=CHX

O

Table 10.12: others are PVC, Table 10.12: others are PVC, acrylonitrile, polypropylene, polymethyl acrylonitrile, polypropylene, polymethyl

methacrylatemethacrylate

8282


PolystyrenePolystyrene

• Polystyrene is nonpolar material and Polystyrene is nonpolar material and dissolves in organic solvents.dissolves in organic solvents.

• PS foam is mostly air, and when it PS foam is mostly air, and when it dissolves it collapses to a much smaller dissolves it collapses to a much smaller volume.volume.

8383


Slime!Slime!

Slime is Slime is polyvinylalpolyvinylalcohol cohol cross-cross-linked with linked with boric acidboric acid

8484


Bubble Bubble Gum!Gum!A A

copolymercopolymer

Bubble Bubble Gum!Gum!A A

copolymercopolymer

Styrene + butadieneStyrene + butadiene

8585


Condensation PolymersCondensation Polymers

HOC

O

COH

O

CO

COCH2CH2OO

+ n HOCH2CH2OH

terephthalic acid ethylene glycol

+ H2O

Polyethylene terephthalate (PET), a polyester

n

n

8686


Polyesters, PETPolyesters, PET

Jackets made from Jackets made from recycled PET soda recycled PET soda bottlesbottles

Soda bottles, Soda bottles, mylar film.mylar film.

8787


Polyesters: MechanismPolyesters: Mechanism

PLAY MOVIE

8888


Polyamides: NylonPolyamides: Nylon

PLAY MOVIE

8989


Polyamides: NylonPolyamides: Nylon

•Each monomer has 6 C atoms in its chain.Each monomer has 6 C atoms in its chain.•A polyamide link forms on elimination of HClA polyamide link forms on elimination of HCl•Result = nylon 66Result = nylon 66•Proteins are Proteins are polyamidespolyamides

9090


Polymer Recycling Polymer Recycling SymbolsSymbols

LDPE = LDPE = Low density PE = 0.910-0.925 g/cmLow density PE = 0.910-0.925 g/cm33

HDPE = HDPE = High density PE = 0.941-0.965High density PE = 0.941-0.965PP = PP = Polypropylene = 0.90Polypropylene = 0.90V = V = PVC (Vinyl chloride) = 1.30-1.58PVC (Vinyl chloride) = 1.30-1.58

Documents

Chapter 10 Carbon: More Than Just Another Element