TO MY PRESENTATION

Amit BiswasID: 143003014Department of Textile engineeringGreen University of Bangladesh

ACRYLIC FIBRE

Acrylics: A manufactured fiber in which the fiber forming substance

is any long chain synthetic polymer composed of at least 85% by weight of acrylonitrile units .  these fibers have an average molecular weight of ~100,000, about 1900 monomer units. 

Acrylonitrile: The substance from which acrylic fibers are made and from

which the generic name is derived was first made in Germany in 1893 .

INTRODUCTION:

Acrylic Fiber Features

Resilient and retains shape Quick drying Resistant to water damage, sunlight and

does not fade Resistant to mold, mildew and insects Flammable

CHEMICAL PROPERTIESEffect of acids Damage by strong concentrated acids. Good

resistance to mineral acids

Effect of Alkali Resistance to weak alkali but affected by strong alkali.

Effect of Solvents Resistance to common solvents

Effect of Bleaches

Resistance to bleaches.

Effect of Heat Most heat sensitive

Effect of Dye Acid, basic, cationic.

Effect of LightResistance but not for long time.

CH2 CH|CN

Chemical Composition and molecular arrangement of Acrylic

PhotopolymerCopolymerGraft polymerBicomponentBlends of various deniersBlends of homopolymer and copolymerHelical, nonreversible crimpReversible crimpSurface modifiedVarious cross section—round, acorn,dog-boneVariable dyeability –cationic,disperse,acidic,basicSolution dyed

FAVOURABLE UNFAVOURABLE

Light weight Has only fair strength 20% weaker when wet

Good drape, Wool like hand Hydrophobic fiber(1 1/2% moisture regained )

Good resiliency and elasticity Static and pilling a frequent problem

Excellent resistance to sunlight and weathering Abrasion resistance is fair

May be washed or dry-cleaned Resistant to water borne stains and odors

Good quality of wicking which adds to comfort in wearing

Durable

Highly degradation resistant to dilute acids, both organic and mineral .orlon is resistant to strong acids as well .also to dilute Alkalis ,likely to be found in home cleansing agents.Dyeable to bright shades with excellent fastness

PHYCAL PROPERTIES

Cross section of acrylic fiber

The acrylic process is a "one step technology", with the following main

characteristics

1. polymerization in solution 2. direct feeding of the dope to spinning 3. wet spinning.4. DMF as solvent for both polymerization and spinning

Manufacturing process of acrylic

Comparison OF Acrylic and woolS.NO FIBER PROPERTIES ACRYLIC WOOL

1 EFFECT OF ALKALIES Resistant to weak Alkalis Harmed

2 EFFECT OF ACIDS Resistant to most acids Resistant to weak acids

3 EFFECT OF SOLVENTS Can be dry cleaned Dry-cleaning recommended

4 EFFECT OF SUNLIGHT excellent resistance Low resistance

5 STABILITY Generally retains shape Subject to letting shrinkage

6 PERMANENCE OF CREASES

Creases can be set and removed by heat

Creases set by heat and moisture

7 EFFECT OF HEAT Thermoplastic sticks at 450-490o F

Scorches easily , becomes brittle at high temperatures

8 RESISTANTANCE TO MOTHS AND FUNGI

resistant HARMED BY MOTHS ,mildew forms on soiled , stored wool

9 EFFECT OF WATER None May felt or mat, noticeable odor when met.

Raw wool acrylic

Uses of AcrylicThe principal end uses for this fiber include:

Dresses Blankets Carpeting Children’s Garments Outdoor products such as bunting

and canopies. Sweaters Gloves Mats Knit Jersey Wrinkle resistant fabrics Pile and Fleece fabrics rugs

Thank you