Graft copolymers, with cellulose

Condensation of an acrylic acid-cellulose graft copolymer with 5-amino-l,10-phe-nanthroline (233) has been utilized to provide polymer (234 Scheme 113) with the phenanthroline ligand oriented optimally for complexation (77MI11110). The polymer was described as exhibiting a strong sorption capacity for Co2+ and Cu2+ ions. 

Graft Copolymerization. Graft copolymers of cellulose and cellulose derivatives were prepared in a quartz reactor containing 0.5 g oven dried sample, 10 ml monomer and 100 ml water at 45°C. The grafting mixtures or solutions were photo-irradiated with the ultraviolet light of X > 254 nm and X >... 

Variables affecting the homopolymer yields in acid have been examined and include radiation dose, dose-rate and concentration of monomer in solvent. Water is shown to have a different effect to acid. M values on all homopolymers from the above runs are lower in acid than in neutral solution. The significance of the molecular weight data in grafting and homopolymerisation is discussed especially with respect to possible commercial applications of the graft copolymers of cellulose. 

Figure 5. GPC curves of 1, cellulose nitrate 2, polyf methyl methacrylate) 3, physical mixture of cellulose nitrate and polyf methyl methacrylate) and 4, graft copolymer of cellulose nitrate-g-poly-(methyl methacrylate). (Reprinted, with permission, from Ref. 21. 

Cellulose constitutes a ubiquitous and renewable natural material that has great potential for chemical conversion into high-quality adhesive products. The resurrection of research and development of cellulose derivatives, such as cellulose esters and ethers, cellulose graft-copolymers, and cellulose polyblends, has instituted new avenues for adhesive applications. There is little doubt that new solvent systems for cellulose have created the potential of developing uniform cellulose products with superior properties for adhesive applications. 

Graft copolymers of cellulose with glycidyl methacrylate yield cation-exchange materials with sodium hydrogen sulfite100) and cationites with ammonia, monoethanolamine and diethylamine. 

It is also interesting to note that the nitration of cellulose in the graft copolymer with PS occurs much more slowly than that of the cotton cellulose used for grafting (Fig. 7). 

A separate and promising trent in the chemical modification of cel-lul< e is the synthesis of graft copolym d cellulose with various vinyl and dmxs monomers. This is a big problem dind ndent interest our results in this line obtained in recent years have b n published in special revies articles (5). 

Kang HL, Liu WY, Liu RG, Huang Y (2008) A novel, amphiphilic ethyl cellulose grafting copolymer with poly(2-hydroxyethyl methacrylate) side chains and its micellization. Macromol Chem Phys 209 424 30... 

Kang HL, Gao X, Liu RG, Huang Y (2012) Synthesis and properties of cellulose graft copolymers with well-defined architecture. In Liebner F, Rosenau T (eds) Functional materials from renewable sources. ACS symposium series, vol 1107. American Chemical Society, Washington, pp 109-131... 

Chauhan GS, Guleria L, Sharma R. Synthesis, characterization and metal ion sorption studies of graft copolymers of cellulose with glycidyl methacrylate and some comonomers. Cellulose 2005 12 97-110. 

Similar processes have been observed using metal(O) vapor deposition on polymers, metal dissolution in the presence of polymers, mechanochemical syntheses involving macromolecular ligands, etc. However, transition metal reduction is most often observed in these processes. Hence compounds of and are reduced relatively easily, as it was shown with PVA as a model compound. A graft copolymer of cellulose is reduced in a similar manner. The degree of reduction depends on the pH of reaction medium (maximum of 70% at pH 4.5-5.0), and if die resulting is fuUy bound to the polymer. 

Copolymers of diallyl dimethyl ammonium chloride [7398-69-8] with acrylamide have been used in electroconductive coatings (155). Copolymers with acrylamide made in activated aqueous persulfate solution have flocculating activity increasing with molecular weight (156). DADM ammonium chloride can be grafted with cellulose from concentrated aqueous solution catalysis is by ammonium persulfate (157). Diallyl didodecylammonium bromide [96499-24-0] has been used for preparation of polymerized vesicles (158). 

Emulsion polymerizations of vinyl acetate in the presence of ethylene oxide- or propylene oxide-based surfactants and protective coUoids also are characterized by the formation of graft copolymers of vinyl acetate on these materials. This was also observed in mixed systems of hydroxyethyl cellulose and nonylphenol ethoxylates. The oxyethylene chain groups supply the specific site of transfer (111). The concentration of insoluble (grafted) polymer decreases with increase in surfactant ratio, and (max) is observed at an ethoxylation degree of 8 (112). 

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