fibres and plastics

 Fibre - Fibre is a single and elongated piece of material which is similar to threads.


Monomer - Mono - single, Mer- unit 

Polymer - Poly - many, Mer - unit

Polymer are formed from repeating units of monomer, 'Poly' means many,  'mer' means unit .


Natural fibre silk 

Silk is a smooth fibre, it is obtained from pupa of silkworms 

Silk rope is equally strong as equally thick metal wire.

Silk is first discovered in China by yellow empress Leizo and kept as secret for thousand of years.

Cultivation of silkworms to produce silk is called Sericulture. 


10 kg of cocoon -> 1kg of silk 

The cocoon produced by the silkworm is treated with hot air, steam and boiling water to obtain silk strands. 


Silk produced by Bombyx Mori is considered to be the best quality 

Bombyx Mori feeds on mulberry leaves 


Process by which silk is obtained is somehow cruel, killing the silkworms but we can find another alternative to silk and at that time scientists wanted too because of the high rocketing prices of silk and disease that hit silkworm 


Artificial Silk - Rayon 

Rayon is invented by Hilaire de chardonnet 

Rayon is obtained by the chemical treatment of wood pulp 

It is made out of cellulose that is natural but it is considered as the synthetic fibres due to chemical treatment of it 

First company to manufacture rayon is 

Du Pont 


First completely synthetic fibre - Nylon 

Nylon was first discovered by Wallace Carothers 

Nylon is a first completely man made fibre

Carothers in DuPont was working with amides and discovered Nylon 

Nylon is so strong that it is used in parachutes and rock & mountain climbing 


Commercial production of Nylon began in 1939. 


Polyester 

Polyester is a man made or synthetic fibre 

Polyester was discovered in April 1930 even before nylon by lab assistant of carothers but carothers neglected it and invented nylon.

PET was patented by Winfield and Dickson in 1941 

PET- Polyethylene teraphthalate 


Terylene was the first polyester 

It was first manufactured by ICI (Imperial Chemical Industry) 


Repeating units of a chemical called esters forms polyester 


Polyester + cotton results in Polycot 

Polyester + wool results in Polywool 


Polyesters can be blended with cotton o form Polycot and with wool to form Polywool 


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