Graft copolymerization of methacrylic acid (MAA) onto starch using a potassium persulfate/sodium thiosulfate redox initiation system was investigated. Emphasis was placed on the promotion of graft formation while minimizing homopolymerization. This could be achieved through a thorough investigation into the major factors affecting the polymerization reaction such as the state of the starch, redox ratio of the initiator, monomer and initiator concentrations, time and temperature of polymerization, and material-to-liquor ratio. The results obtained imply that the magnitude of the polymer yield including total conversion, graft yield, and homopolymer are determined by these factors. The yield is favored under the influence of higher temperature, longer time, short liquor, and increased monomer and initiator concentrations. A poly-(MAA) -starch graft copolymer is the main product of the polymerization reactions only when starch was preswelled (through cooking prior to grafting). Moreover, this grafted product could be precipitated by more dilution with water and easily separated by filtration. Hence, the results of the current work formed the basis of a novel method for the synthesis of poly(MAA) -starch graft copolymers. The mechanisms involved in the synthesis are reported.

Grafting of methacrylic acid (MAA) on starch, poly(vinyl alcohol) (PVA), and a mixture of starch and PVA, using a potassium persulfate/ sodium thiosulfate redox initiation system was carried out. Polymerization was studied with respect to graft yield, homopolymer formation and total conversion. These polymerization criteria were found to depend largely on the concentration of both MAA and initiators, duration and method of polymerization.The results reveal a number of interesting points which reflect the impact of the condition of the treatment. The main product of the polymerization reaction [poly(MAA)starch/PVA graft copolymer] was formed and precipitated during polymerization and can be easily separated by filtration as pure product.Application of these copolymers to cotton fabric was also carried out to evaluate the suitability of such modified products as sizing agents.

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An effective two‐stage method has been developed for imparting antimicrobial properties to regular polyethylene terephthalate (R‐PET), polyethylene glycol modified polyethylene terephthalate (PEG‐M‐PET), R‐PET/Cotton blend (R‐PET/C) and PEG‐M‐PET/Cotton blend (PEG‐M‐PET/C) fabrics. The method consists of partial hydrolysis of the fabrics to create carboxylic groups in PET macromolecules followed by subsequent reaction with dimethylalkylbenzyl ammonium chloride (DMABAC) under alkaline conditions. The reaction conditions such as pH, reaction temperature and time, carboxylic content, and DMABAC concentration were studied. Characterization of the finished fabrics was carried out through scanning electron microscopy (SEM) and Fourier transform infrared spectra (FTIR). All the modified PET fabrics showed excellent antibacterial activity towards Gram‐positive (Bacillus mycoides), Gram‐negative (Escherichia coli), and nonfilamentous fungus (Candida albicans). The achieved antimicrobial functions on the PET fabrics are durable in repeated laundering processes. Even after laundering 10 times the fabrics could still provide more than 85% of its antimicrobial activity against B. mycoides, E. coli, and C. albicans. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

The present work aims to assess: (a) The effectiveness of nylon nonwoven fabrics containing antimicrobial substance and grafted with PMAA, PDMAEMA and the blended fabric containing the above mentioned two types of nonwoven fabrics for metal ions (Cu 2+ , Pb 2+) and chromate (Cr 2 O 7) 2recovery from wastewater; (b) The amount of the ion-exchanger used; and (c) The desired quality of product water (breakthrough point) on the operating capacity of textile under investigation. The main objective of this study is to investigate the possibilities of the final effluent in order to comply with the National Environmental Regularity standard for wastewater discharge into the public sewage network. The Cu 2+ and Pb 2+ removal efficiency by the above mention textile types was studied by batch adsorption and column runs methods. It was found, in case of applying batch adsorption method that, the maximum removal of Cu 2+ (92%) takes place when nylon grafted with PMAA nonwoven fabric was used. The application of blended nonwoven grafted with PMAA and PDMAEMA fabric paves the way for high sorption (79%) of Cu 2+ from wastewater. The Cu 2+ removal with grafted with PDMAEMA nonwoven fabric slightly increased relative to control fabric. The maximum ion removal % of Pb 2+ (80-82%) was attained upon using all three types of grafted textiles, irrespective of the types of grafted polymer. Column method was used for determination of Cu 2+ and Pb 2+ removal efficiency by using the three types of grafted nylon-6 nonwoven fabrics. The copper and lead free effluents, breakthrough points and breakthrough capacities for the ion-exchangers under investigation were obtained Chromate removal efficiency by using Nylon non woven antimicrobial fabrics grafted with PDMAEMA was studied. For this anion exchanger fabric chromate free effluent, chromate breakthrough point and breakthrough capacity were also obtained.