Improving of surface properties of PET with environmental … · 2018. 1. 4. · 18° International Symposium on Plasma Chemistry – Kyoto, Japan Improving of surface properties

18° International Symposium on Plasma Chemistry – Kyoto, Japan

Improving of surface properties of PET

with environmental friendly Atmospheric Pressure Plasma

treatments

Domenico D’Angelo Environment Park S.p.A.

22nd INTERNATIONAL IFATCC CONGRESS – Friday, May 7, 2010 - Stresa

Ionisation degree.

Plasma

22nd International IFATCC Congress – Friday, May 7, 2010 Stresa - Dr. Domenico D’Angelo

Ionisation degree = 1

Termonuclear plasma

Ionisation degree = 10-7 -10-4

Conventional plasma chemical

systems

Completly ionised plasma Weakly ionised plasma

Plasma and plasma chemistry

Plasma

Thermal plasma Non thermal plasma

Pressure range

T0 = Te

T0 « Te


Thermodynamic equilibrium


Gas pressure Strengths Disadvantage Low

(~ 0.01 kPa) Uniformity Batch process

Expensive equipment Subatmospheric

(~ 1 kPa) Uniformity Batch process

Expensive equipment

Atmospheric

(~ 100 kPa) In-line

speed Only in some plant

uniformity

Typical pressure ranges



Plasma System: Atmospheric Plasma Pressure Glow Dielectric Barrier Discharge

•  Two planar modular stainless steel electrodes •  Self plasma-impedance adapting glow discharge •  Lab scale version of production-size unit •  Roll to roll system:10m/min max velocity •  Max Power 2500W •  4 indipendent gas lines •  2 independent monomer lines •  1 micro-droplets dispenser •  pre-heating system


•  Vertical electrodes configuration suitable for textiles and polymeric rolls. (natural and polymeric fibers, PP,PE,PET etc)

•  Horizontal electrodes configuration:possibility to treat rigid plane surfaces (wood laminates, polymeric sheets,cellulose

APP-DBD PLASMA SYSTEM: CHANGEABLE ELECTRODES CONFIGURATION

Why plasma technologies?


Intrinsic properties

Additional functionalities

Traditional finishing Plasma processing

Flexibility

Strenght

“Hand” or touch

Low specific Weight

Require the use of large amount of chemicals, water, and energy

Comparison of plasma treatment vs. traditional processes

Parameter Plasma Traditional Solvent None (gas phase) Water Energy Electricity Heat

Type of reaction Complex Simple Deepness of the

Treatment Very thin layer Bulk of the fibers

New treatments High potentialities Very rare Water and energy

consumption Low High

Pollution Very low High

Equipment Totally new Slow evolution


Textile processing

Wet washed polyester fabric

Application of the finish

Drying Plasma treatment

Polymerization

Finished polyester

Drying



Dyeing

HO CH2CH2OC COO CH2CH2OHn

OO

Dye

Dye

DyeDye

Dye

Dye

1 2 3

The dyeing process is industrially performed above the glass transition temperature

Polyester/natural blends

HO CH2CH2OC COO CH2CH2n

OO

OC

O

COCH2CH2OC

O O

SO3H


OO

OC

O

COCH2CH2OC

O O

N


OO

OC

O

COCH2CH2OC

O

CH2CH2CH2CH2CH2CH2

O

Dyeing



OO

All these modifications lead to a variation of the bulk properties of the textile


PLASMA

electrons gas

Ionisations Dissociations Excitation

Positive ions Negative ions Radicals Molecules Light

Etching Grafting Deposition Activation NH2


Plasma surface interaction

Ka

Kb

Kc

KdKe

KfKg

KhKi



Parameter used in APP-GDBD treatments

POWER

TIME

SCCM PRECURSOR

Sample Gas and precursors Power (W) Time (sec)

K/S Untreated - - - 0.32

B He 100% 1000 60 0.52 C N2 75% 1000 60 0.58

A1 O2 75% 1000 60 0.71 A2 O2 55% 1000 60 0.67 A3 O2 35% 1000 60 0.69 A4 O2 15% 1000 60 0.61

D Activation with O2 75% 1000 60 0.71

NH3 15% 1000 60

E Activation with O2 75% 1000 60 0.93

HEMA/NH3 mixture 350 60

0,0

1,0

2,0

3,0

4,0

5,0

6,0

1,2 1,4 1,6 1,8 2,0 2,2 2,4 2,6

Energy input W/F [W/sccm]

Depo

sitio

n ra

te [n

m/m

in]

TEXTILE STRUCTURE

Structure

O

O

O

O

O

O

O

O



Acid Blue (127:1)

Dyeing procedure

Basic Red 18

RRSK2

)1(/2−

=K = absorption coefficient

S = scattering coefficient

R = reflection factor

OES analysis


EXCITED SPECIES WAVELENGTHS He* 447.1 nm He* 501.7 nm H* 486.1 nm H* 656.3 nm O* 777.4 nm O* 844.6 nm CO 519.8 nm CO 561.0 nm

Hem + O2 à He + O* + O+ + e

He+ + O2 à He+ + O + O*

He+ + O2 à He + O+ + O*

Penning reaction:


XPS analysis


OOO1s 1

O1s 2 C1s 1 C1s 3

C1s 2

D

C

B

A4

A3

A2

A1

0.140.544.833.4561.76PET O2/NH3

0.090.543.1034.3062.59PET N2

0.030.581.9436.0162.06PET He

0.020.521.3233.8364.86PET He/O2

0.020.581.1236.4562.47PET He/O2

0.010.560.9335.8863.25PET He/O2

0.010.690.7640.5458.69PET He/O2

-0.445-30.8269.18PET untreated

-0.4-28.671.4PET theorical

N/CO/CN %O %C %

D

C

B

A4

A3

A2

A1

0.140.544.833.4561.76PET O2/NH3

0.090.543.1034.3062.59PET N2

0.030.581.9436.0162.06PET He

0.020.521.3233.8364.86PET He/O2

0.020.581.1236.4562.47PET He/O2

0.010.560.9335.8863.25PET He/O2

0.010.690.7640.5458.69PET He/O2

-0.445-30.8269.18PET untreated

-0.4-28.671.4PET theorical

N/CO/CN %O %C %


Non treated APP treated


OOO1s 1

O1s 2 C1s 1 C1s 3

C1s 2

XPS analysis

The deconvolution of the O1s electron peak shows the change in the relative proportions of oxygen singly and doubly bonded to carbon.


Two competitive processes

COOCH2CH2OCO

COOCH2CH2OCO 2H

COOCH2CH2OCO COOCH2CH2OCO

In the sample B there is a strong crosslinking, depending on the high percentage of helium and low percentage of oxygen.

Conclusion


The treated PET showed significant improvement in the water absorbance and the dyeability An increase in color depth upon dyeing was obtained after treating PET fabrics with the two types of plasma treatment performed in this work The introduction of hydrophilic groups increases the affinity of PET fibers for dyes The reinforced crosslinked layer that stabilized the surface is formed under the action of the He active species, while the oxigen species induce the formation of an oxidized polymeric structure The presence of O2 in excess induces a depopulation of the excited levels of He, particularly the metastable ones, a fact which is reflected by a considerable decrease of the stability of the surface properties of the treated polymer The results proved the suitability of plasma treatment in textile industry especially in PET dyeing and processing by enhancing the wettability of the polyester fibers

Thanks for your attention !!!



Department of General Chemistry and Organic Chemistry and NIS, Interdepartmental Center of Excellence, University of Torino

Foundation Bruno Kessler, Trento

GRINP s.r.l., Torino

Dr. Guy Buyle, Centexbel, Belgium

Acknowledgements

Documents

Improving of surface properties of PET with environmental … · 2018. 1. 4. · 18° International Symposium on Plasma Chemistry – Kyoto, Japan Improving of surface properties