Graft copolymerization vinylpyrrolidone

Radical Graft Copolymerization of Vinylpyrrolidone onto Poly(vinylalcohol)... 

A rather similar dependence was observed by Hoffman et al. 98) for heparin covalently immobilized on silicone rubber, which had been pre-modified by graft-copolymerization of hydroxyethyl methacrylate and N-vinylpyrrolidone (Table 11). 

Several graft copolymerizations were described by Ballantine (17, 64), Henglein (104, 105) and coworkers. Different monomer-polymer systems were examined styrene on polymethyl methacrylate, poly-2, 5-dichlorostyrene, polytetrafluoroethylene, polyethylene, polypropylene and polyisobutylene, acrylonitrile on polyethylene, rubber, polymethyl methacrylate and dimethyl polysiloxane, vinylpyrrolidone and acroleine on polymethyl methacrylate. The results agree with the preceding ones moreover they show the influence of the swelling and diffusion of the monomer into the polymer. 

Graft copolymerization of TV-vinylpyrrolidone onto polyethylene terephthalate (Dacron) [114]. 

Graft copolymerization of a mixture of methyl methacrylate and TV-vinylpyrrolidone onto cellulose [120]. 

Graft copolymerization of vinyl chloride onto poly(vinylpyrrolidone) [254]. 

Other methods that have been reported include inducing the cyclization reaction by incorporating thioamide groups [491], copolymerized AF-vinylpyrrolidone [492], or vinyl halogen monomers in copolymerized or grafted form [493]. Stabilizers based on maleic acid are also effective [494,495]. Reviews on the subject have been published by Brown [496] and Krcma [497]. 

Because poly(vinylpyrrolidone) is a water-soluble polymer, cross-linked copolymers of this material imbibe water and swell. This fact has been applied to the possible preparation of contact lenses which are soft and flexible on contact with water or aqueous fluids not only by grafting appropriate monomers to preformed PVP but also by direct copolymerization of N-vinylpyrrolidone with other comonomers. For example, a cross-linked hydrogel was prepared by terpolymerizing A-vinylpyrrolidone, methyl acrylate, and tetraethylene glycol dimethacrylate in the presence of AIBN [44]. 

MA-A -vinylphthalimide copolymerization, 401 MA-A -vinylpyrrolidone copolymerization, 401 MA-A -vinylsuccinimide copolymerization, 401 maleimide polymerization, 265 naphthalene effects on styrene-MA pair, 370 poly(styrene-co-MA) grafting on poly butadiene, 470... 

Many graft copolymers have been made by free radical copolymerization of co-styryl or co-methacryloyloxy macromonomers and various comonomers. Special interest has been devoted to amphiphilic copolymers involving a hydrophilic backbone and hydrophobic grafts, or vice versaf Poly(perfluoroalkyl methacrylate) and poly(stearyl methacrylate) are typical examples of hydrophobic polymers, whereas poly(hydroxyethyl methacrylate) or poly(vinylpyrrolidone) are examples of nonionic hydrophilic chains. Such graft copolymers have found a number of applications as surface modifiers or coatings because of their ability to give intramolecular phase separation (surface accumulation phenomena ). 

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