viscose fiber characteristics

 Characteristics of viscose fiber :

1. Molecular structure : Regenerated cellulose . 

2. Microscopic features : 

a)Can be produce fiber as filament and staple fiber 

b)Cross section is not even and graved side and likely to be circle .

c) Color is white 

d)Fiber can be produce in three type : Dull , Bright and super bright . 

3. Physical properties of viscose fiber  : 

a)Tenacity : regular -2 , high wet modulus 4.5. It depends on kinds of rayon and polymerization process . 

b) Stretch and elasticity : Changable based on production process . Regular , high modulus and high weight modulus elongation at break is  in sequence of 20%, 13% , 12% . If we elongate 2% then it recover as sequence 80%, 85%, 95%. 

c)Resiliency : Less 

d) Abrasion resistance : Less 

e) Permanent volume : Regular quality is not good but high wet modulus is very good . After wash fabric be some loose . During yarn and fabric can be stretch easily . 

f) Moisture regain : 12-13%

g)Relative humidity : 1.52

h) Flammability : It burn easily and early . 

i)Heat resistance : 150°C temperature can reduce its strength . 

j)Lusture : Medium to bright 

k) Electrical and thermal conductivity : Static electricity can be conductive , charge bearing capacity is very good. 

Chemical properties of viscose fiber : 

a)Action of Acid: In strength acid fiber be destroyed and weak acid can not be destroyed . For example : 2% acetic acid or formic acid can not loss viscose rayon at room temperature . Concentrated sulphuric acid , hydrochloric acid and nitric acid can not destroy viscose fiber . After reaction of acid if not washed good then after dry it can be hard and brittle . 

b) Action of alkali : In weak alkali it is very protective but concentrated alkali can hamper the fiber . 

c)Action of bleach : Strong oxidizing agent may be loss viscose fiber . Oxidizing and reducing both bleach can be use . 

d)Action of solvent : Pine oil , chlorinated hydrocarbon , benzene , toluene, xylene, gasoline , carbon tetrachloride etc are used in viscose rayon and they never damage viscose rayon fiber . But in cupramonium  hydroxide can dissolve viscose rayon. 

e) Action of sun light and heat : In ultraviolet ray may be reduce . above 300°F can loss strength .Calendering temperature is 275°F . 

f) Action of Mildew : Moulds , mildew , fungus , bacteria reduce the quality of viscose rayon . Microorganism can destroy viscose fiber based on the size yarn or fabric how to keep . So for this dry viscose rayon never be attack by moulds and mildew . 

g)Action of  insects: Insects can make hole in fabric. 

h)Dye ability : Viscose fiber dye absorbency is better than cotton .