Defence Science Journal, Vol 50, No.4, October 2000, pp.425-433 @ 2000, DESIDOC SHORT COMMUNICATION Radiochemical Graft Copolymerisation of 2-Hydroxy Ethylmethacrylate onto Polyamide-6, 6-Nylon Inderjeet Kaur, Raghuvir Barsola, B.N. Misra and Ghanshyam S. Chauhan Himacha/ Pradesh University, Shim/a - 71005 ABSTRACT Polyamide-6,6-nylon has been modified by radiation-induced graft copolymerisation of 2-hydroxy ethylmethacrylate (2-HEMA) in nonaqueous medium (ethanol). No homopolymer formation was observed during grafting. Optimum conditions for affording maximum percentage of grafting have been evaluated. Maximum percentage of grafting (170 per cent) was obtained at a total dose of 0.74 x 104 Gy using 2-HEMA (8 x 10-3 moles) in ethanol (10 ml). The grafted samples were characterisedby thermogravimetric analysis and it was observed that grafting slightly decreased the thermal stability of the polyamide-6,6 fibre. Dyeing properties ofpolyamide-6,6 fibre and grafted fibre have also been investigated. product improvement and search of even better polyamide-type. 1 INTRODUCTION The dominant role of polyamide in the field of industrial fibres is related to their high toughness, strength, ability to absorb high velocity impact and the specific tailoring ofpolyamide towards the intended industrial end-use. Polyamide is specifically used in seat belts in automobiles, in parachute cloth and in diverse industrial applications because of its excellent abrasion resistance. Polyamides are high modulus polymers that have. applications where high molecular weight and lightweight are required. Nylon shows distinct advantage over met~ls and ceramics on property-weight basis. Currentlyavailable commercial polyamides fulfil considerable number of end-use requirements. They have certain deficiencies in selected applications. Their high cost, relatively poor heat resistance, light fastness, only fair pilling resistancel, etc., have directed research efforts towards Improvement in stain resistance, static and soil resistance, increased ironing temperatures, increased dyeabifity, etc., may be achieved by reacting the fibres with a suitable material. Adipoyl chloride- treated with polyamide-6,6 fibres have increased the melting temperature (T m) and the dyeability properties2-4. Increase in crystalline Tm has also been observed when the polyamide fibre is treated with cyanuric chlorides, ZnC 126 HCHO7 and SnC128. However, modification of polyamide fibre by grafting appropriate vinyl monomers has been extensively studied but only limited commercialisation has been obtained. Grafted nylons have generally improved the physical properties over the conventional nylons. Properties improved by grafting a polymer, such as polyacrylic acid in the form of its sodium salt onto Revised 19 July 2000 425