Graft copolymerizations onto cellulosic fibers

Also other oxidants have been used successfully to initiate graft copolymerization onto cellulose substrates. Toyo Rayon (79) achieved grafting by pretreatment of viscose rayon fibers with potassium permanganate-sulfuric acid and contacting it subsequently with acrylonitrile. Methyl methacrylate is being grafted to rayon when heated together with potassium bromate, as claimed by Asahi Chemical Industry... 

Sakurada, I., T. Okasa, Hatakeyama, and F. Kimura. Radiation-induced graft copolymerization onto cellulose and polyvinyl alcohol fibers with binary mixtures of comonomers. J. Polymer Sci. C 4, 1233 (1964). 

B. Ranby and C. Rodehed, "New Graft Copolymerization onto Cellulosic Fibers", in "Review and Preview in Polymer Science. A Tribute to Herman Mark" (Ed. G.A. Stahl), ACS Mon. Ser. 1981. 

Arthur, J.C., Jr., Free-radical initiated graft polymerization of vinyl monomers onto cellulose, in Graft Copolymerization of Lignocellulosic Fibers, Hon, D.N.-S., Ed., ACS Symposium Series, No. 187, American Chemical Society, Washington D.C., 1982, p. 21. 

Desirable and targeted properties for cellulose fibers can be obtained through graft copolymerization, in order to meet the requirements of specialized applications. Graft copolymerization is one of the best methods recommended for modif5dng the properties of cellulose fibers. Different binary vinyl monomers and their mixtures have been graft copolymerized onto ceUulosic materials for modifying the properties of numerous polymer backbones (Kaith et al. 2005 Kalia et al. 2009). 

Graft copolymerization can be initiated by physical or chemical processes. This paper describes methods for chemical initiation of grafting onto cellulosic fibers with special emphasis on recent developments, i.e. studies from the last 10-15 years. The initiation reactions may be free radical or ionic processes. The grafting reaction may also be a condensation or addition process. 

Peracetic acid, formed in situ from acetic acid and hydrogen peroxide in acid aqueous solution, was found to initiate graft copolymerization of vinyl monomers, e.g. methyl methacrylate and 4-vinyl pyridine, onto wood and cellulosic fibers at a good rate (1-3 h time) at 60°C2. The initiati on reaction is not specific for grafting and considerable amounts of homopolymer is formed. 

Graft Copolymerization of Vinyl Monomers onto Cellulosic Fibers... 

As a typical example, a characterization of the product obtained by mutual graft copolymerization of styrene onto cellulose fiber is described in some detail2s ... 

Infrared spectroscopy is a useful tool to identify functional groups through vibrational frequencies in polymers to evaluate changes in structure This research was focused in graft copolymerization of Hydroxyethyl methacrylate (HEMA) onto chicken feathers fibers (CFF) and carboxymethyl cellulose (CMC), evaluating effect of reaction conditions (time reaction, monomer concentration, initiator concentrations) on grafting yield and probe presence of HEMA in copolymers by means Infrared Spectroscopy (IR). 

Thakur VK, Singha AS, Misra BN (2011) Graft copolymerization of methyl methacrylate onto cellulosic biofibers. J Appl Polym Sci 122(l) 532-544. doi 10.1002/app.34094 Thakur VK, Singha AS, Thakur MK (2012a) Green composites from natural fibers mechanical and chemical aging properties. Int J Polym Anal Charact 17(6) 401-407. doi 10.1080/... 

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