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With increasing awareness of environmental concerns, various chemical finishes for processing of textiles have been discussed. In this paper major changes which have occured to satisfy the consumer's demand in terms of comfort, easy care, health, and hygiene are reviewed.

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SYNOPSISAcrylonitrile ( A N ) was copolymerized with acrylic acid ( AA) , methacrylic acid ( M A A ) , and itaconic acid (IA) by the aqueous suspension method at 40°C with ammonium persulfate and sodium metabisulfite as the redox initiator. The reactivity ratios for the AN-AA and AN-IA systems were also calculated by the Finemann-Ross and the Kelen-Tud6s methods. Higher r2 (AA) for the AN-AA system in comparison to r2 ( I A ) for the AN-IA system indicates greater reactivity of AA toward the propagating species. The influence of comonomers on intrinsic viscosity, tacticity, and number-average sequence lengths was studied. 13C-NMR spectra revealed that A N copolymers having approximately 2 mol % of AA have a greater percentage (> 30% ) of isotactic content than of homopolyacrylonitrile. Tacticity has also been calculated from infrared spectra of the polymers using stereospecific absorption bands at 1250 and 1230 cm-' . 0 1993 John Wiley & Sons, Inc. INTRODUCTIONPolyacrylonitrile ( PAN ) is modified to improve its properties by incorporation of suitable comonomers ' during polymerization. Modification of PAN by acidic comonomers increases its hydrophilicity2 and helps in the cyclization of nitrile groups during heat treatment for thermal stabilization of acrylic fib e r~.~~~ Therefore, the incorporation of certain acidic comonomers is prevalent in the synthesis of the copolymers used for the manufacture of special acrylic fibres (SAF) and as precursors of carbon fiber^.^ The copolymerization of acrylonitrile (AN) with some acidic comonomers, viz., acrylic acid and itaconic acid, along with a third monomer is reported in the patent literat~re.',~ AN may be polymerized with a number of comonomers by various methods such as solution, emulsion, aqueous suspension, and solvent water suspension p~lymerization.~ Studies reported on the polymerization of PAN homopolymer include various aspects such as ( i ) the effect of the method of polymerization on properties of the * To whom correspondence should be addressed.Journal of Applied Polymer Science, Vol. 49, 823-833 (1993) 0 1993 John Wiley & Sons, Inc.CCC OOZl-8995/93/050823-11 polymer' and (ii) the effect of the various initiat o r~.~-"For aqueous suspension polymerization, three loci of polymerization have been reported by Peebles.12 Since AN is partly soluble in water, a twophase liquid system can exist, in which one phase would be a monomer-rich phase, while the other is a monomer-poor phase. The distribution of comonomers between these two liquid phases would influence the course of polymerization. Initiation and some propagation would occur in the aqueous phase prior to the precipitation of the growing radical. The second locus of polymerization occurs at the particle-solution interphase known as the surface polymerization. The third loci of polymerization would be interior polymerization through buried free radicals, which is controlled by the diffusion of monomer to the active site. However, interior polymerization becomes less important as the polymerization t...