Lecture 8 (Synthetic Fibers)

CH0204 Organic Chemical Technology

Lecture 12

Chapter 4 Synthec fibers

Balasubramanian S Assistant Professor (OG) Department of Chemical Engineering

Balasubramanian S 1 Overview of topics

Chapter 4 Synthec Fibers

1 Acrylics

2 Polyamides

3 Polyesters

17/02/11 Balasubramanian S 2 Synthetic (or man-made fibers)

What are Synthec Fibers?

The clothes that we wear are made up of fabrics

Fabrics are made up of fibers

Depending on the sources the fibers are classified in two types 1. Natural and 2. Synthec

Natural fibers are the fibers which are obtained from plants and animals e.g. silk and wool

Synthec fibers are made by human beings or also called as man- made fibers Nylon, Polyester, Rayon etc.

Balasubramanian S 3 Synthetic (or man-made fibers)

Natural Fiber, Silk wool

Balasubramanian S 4 Synthetic (or man-made fibers)

Synthec Fibers

Nylon

Polyester

Balasubramanian S 5 Synthetic (or man-made fibers)

The first synthec or man-made fiber is cellulose nitrate and the next synthec fiber is regenerated cellulose or viscose.

Some of the man-made fibers emerged aer 1940’s were acrylics, polyamides, polyesters and polyolefin.

The uses of man-made fibers depend upon the nature of the individual fiber. Clothing, Carpets, and Upholstery are all made largely, or wholly, of synthec fibers.

Balasubramanian S 6 Acrylics

Acrylic fibers are synthec fibers made from a polymer (polyacrylonitrile) with an average molecular weight of ~100, 000 about 1900 monomer units

The Dupont Corporaon created the first Acrylic fibers in 1941 and trademarked them under the name “Orlon”

Balasubramanian S 7 Polyamide (Nylon fiber) Production

Adipic Acid

Water Hexamethylene diamine Process Acec acid Polyamide (Nylon) Nitrogen

Air Steam

Balasubramanian S 8 Polyamides

A polyamide is a polymer containing monomers of amides.

They occurs both naturally and arficially.

Polyamides are commonly used in texles, automoves, carpet and sports wear.

Balasubramanian S 9 Polyamides – Method of production

Adipic acid + Hexamethylene diamine

Hexamethylene diammonium adipate (or) nylon salt

Poly(hexa methylene adipamide) or Nylon

Balasubramanian S 10 Polyamides (Nylon)

A heat transfer fluid and is a mixture of biphenyl (C12 H10 and diphenyl oxide (C12H10O) 2 – 3 atm 240 – 280 oc

2 – 3 atm 240 – 280 oc

Balasubramanian S 11 Uses of Polyamides (Nylon)

Used in the manufacture of

1. Unlubricated or non lubricated bearings 2. Bags 3. Fabrics 4. Ropes 5. Fishing line or net

Balasubramanian S 12 Uses of Polyamides (Nylon)

Used in the manufacture of unlubricated or non lubricated bearings

Balasubramanian S 13 Uses of Polyamides (Nylon)

Used in the manufacture of bags

Used in the manufacture of fabrics

Balasubramanian S 14 Uses of Polyamides (Nylon)

Used in the manufacture of ropes

Used in the manufacture of Fish lines or fish nets

Balasubramanian S 15 Polyesters (PET)

Air

Catalyst p-Xylene Process Methanol Polyethylene Ethylene glycol Therepthalate

Water Steam

Balasubramanian S 16 Polyesters (PET) The common polyester fibers are polymers of the ester formed from dimethyl terepthalate and ethylene glycol Producon steps

1. Preparaon of intermediates 2. Polymerizaon of ester monomers

Dimethyl P-xylene Terepthalic acid terephthalate

Balasubramanian S 17 Polyesters (PET)

Polymerizaon is a two stage

1. Monomer is first prepared either by an ester interchange between dimethyl terepthalate and ethylene glycol or by direct esterificaon of terepthalic acid

2. The second stage is the polymerizaon of monomer to yield polyethylene terephthalate (Polyester)

Balasubramanian S 18 Polyesters-PET

H2SO4

Balasubramanian S 19 Uses of Polyesters (PET)

Used in the manufacture of

1. Fabrics 2. Wrinkle free fabrics 3. Hoses 4. V belts 5. Pillows 6. Carpets

Balasubramanian S 20 Uses of Polyesters

Fabric Wrinkle free fabric

Balasubramanian S 21 Uses of Polyesters

Hose V - Belts

Balasubramanian S 22 Uses of Polyesters

Pillows

Carpets

Balasubramanian S 23 Polyesters manufacturers in India

VACMET INDIA LIMITED Filatex India Limited (FIL) Anant Plaza, IInd Floor Noida Office and Plant 4/117-2A, Civil Lines, A-2 Noida Extension, Phase-II, Dist. Church Road, Agra - 282 002, Gautam Budh Nagar (U.P)-201301 Uar Pradesh (INDIA) (INDIA)

Indo Rama Synthecs (India) Limited Relance Industries Limited 31-A, MIDC Industrial Area, Bubori, Barabanki Manufacturing Division Nagpur - 441122 Near Lucknow, Uar Pradesh India

Jiwarajka Texle Industries 220 Atlanta Estate, 2nd Floor, Vit Bha, Goregaon (E), Mumbai 400063

Balasubramanian S 24 Viscose Rayon

Major Steps 1. Alkali Conversion Cellulose + NaoH = Alkali Cellulose + Water

2. CS2 Stabilizaon/Solubilizaon Alkali Cellulose + Carbon disulphide = Sodium Cellulose Xanthane 3. Acid Regeneraon Sodium Cellulose Xanthane +Sulfuric Acid = Rayon + Carbon disulphide + Sodium bisulphate

Balasubramanian S 25 Viscose Rayon

Alkali Conversion

2 – 4 h

2 – 3 days

4 – 5 days CS2 or Carbon di sulphide Acid stabilizaon/solubilizaon Regeneraon

Balasubramanian S 26 References

1. Dryden C. E, Outlines of Chemical technology – for the 21st Century, 3rd edion, East-West Press (2004)

2. Ausn G. T, Shreve’s Chemical Process Industries, 5th edion, Mc Graw Hill Internaonal edions (1984)

Balasubramanian S 27 Thank you

Balasubramanian S 28