Vinyl pyridine polymerization graft

Radiation-indneed grafting is another modification method that utilizes ultraviolet or ionizing radiation to produce active sites on the manbrane snrface for attaching different kinds of groups (IAEA-TECDOC-1465 2005). The polymerization of the monomer grafted to these active sites results in membranes with different properties. The most common monomers used for radiation-induced grafting are vinyl acetate, A-vinyl pyrrolidone, acrylic acid, metacrylic acid, or V-vinyl pyridine. 

Thiohydroxamic esters have also seen applicadon in grafting of polyacrylonitrile onto polyethylene, of polystyrene (PSt), polyacrylamide (PAM), and poly(N-isopropylacrylamide) onto cellulose,and of PS, PMMA, poly(vinyl pyridine), and polyacrylamide onto poly(arylene ether sulfone). The process involves derivatization of a parent carboxy-fimctional polymer to form the thiohydroxamic ester 59 with R= polymer, which then behaves as a polymeric transfer agent. 

Leza, M. L., Casinos, I., Guzman, G. M., Bello, A., Graft Polymerization of 4-vinyl-pyridine Onto Cellulosic Fibres by the Ceric on Method, Angew. Makromol. Chem. 1990,178,1091119. 

Carbon blacks have been reported to be capable of initiating the cationic polymerization of vinyl monomers such as vinyl ethers, indene, and acenaphthylene. The grafting sites of the polymer were based on carboxyl groups present on the surface [88]. The polymerization was inhibited by treatment of the carbon blacks with NaHCOs, CH2N2, pyridine, and DMF. Also, the degree of conversion was found to be dependent on temperature and time of polymerization [89]. 

A series of graft polymers on polychloroprene were made with isobutylene, iso-butyl vinyl ether, and a-methylstyrene by cationic polymerization in solution. The efficiency of the grafting reaction was improved by use of a proton trap, 2,6-di-tertiarybutyl pyridine (50). 

Martin et al (1992) reported synthesis of a variety of monosaccharides with vinyl acrylate in pyridine to obtain 6-acryloyl esters and later on polymerized them in DMF solvent with AIBN as the initiator to give poly(acrylate) products. Enzymatic reactions have been used to synthesize linear polymers with sugar as part of the main chain (Patil et al, 1991b). More recently, several new lipase grafting reactions on polysaccharides have been carried out. Polysaccharides are... 

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