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Lecture 8 (Synthetic Fibers)

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Lecture 8 (Synthetic Fibers) CH0204 Organic Chemical Technology Lecture 12 Chapter 4 Synthe2c fibers Balasubramanian S Assistant Professor (OG) Department of Chemical Engineering Balasubramanian S 1 Overview of topics Chapter 4 Synthe2c Fibers 1 Acrylics 2 Polyamides 3 Polyesters 17/02/11 Balasubramanian S 2 Synthetic (or man-made fibers) What are Synthe2c 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. Synthe2c Natural fibers are the fibers which are obtained from plants and animals e.g. silk and wool Synthe2c 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) Synthe2c Fibers Nylon Polyester Balasubramanian S 5 Synthetic (or man-made fibers) The first synthe2c or man-made fiber is cellulose nitrate and the next synthe2c 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 synthe2c fibers. Balasubramanian S 6 Acrylics Acrylic fibers are synthe'c 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 Ace2c acid Polyamide (Nylon) Nitrogen Air Steam Balasubramanian S 8 Polyamides A polyamide is a polymer containing monomers of amides. They occurs both naturally and ar'ficially. Polyamides are commonly used in tex'les, 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 Uhar Pradesh (INDIA) (INDIA) Indo Rama Synthe'cs (India) Limited Relance Industries Limited 31-A, MIDC Industrial Area, Bu2bori, Barabanki Manufacturing Division Nagpur - 441122 Near Lucknow, Uhar Pradesh India Jiwarajka Tex'le 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 Regenera'on Balasubramanian S 26 References 1. Dryden C. E, Outlines of Chemical technology – for the 21st Century, 3rd edi2on, East-West Press (2004) 2. Ausn G. T, Shreve’s Chemical Process Industries, 5th edi2on, Mc Graw Hill Internaonal edi2ons (1984) Balasubramanian S 27 Thank you Balasubramanian S 28 .
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