Binary-grafting

Ishizu K, Minematsu S. Morphology of emulsion systems stabilized by binary graft copolymer blends composed of polyelectrolyte trunks. Makromol Chem Rapid Commun 1989 10 527-531. 

Burillo, G., Dfaz, A., and Bucio, E. 2006. Characterization of thermo and pH sensitivity of binary graft copolymers onto tetrafluoroethylene. J Mex Chem Soc. 50 1-4. 

Melendez-Ortiz, H.I. and Bucio, E. 2008. Radiation synthesis of a thermo-pH responsive binary graft copolymer (PP-g-DMAEMA)-g-NIPAAm by a two step method. Polym Bull. 61 619-629. 

Binary-grafting Approach to Polymer-grafted CNTs... 

Another binary mixture, namely, (acrylic acid/ acrylamide) was grafted onto carboxy methyl cellulose (CMC) [25]. 

Gaylord et al. [49] reported the dilution and matrix effects in grafting of the styrene/AN binary mixture onto cellulose with K2S2O8 as the initiator. Titledman and coworkers [50] reported the effect of hydroxypro-pylmethyl cellulose on the course of (NH4)2S20 decomposition and claimed a route for grafting of vinyl monomers onto the polymer backbone. The decomposition of the peroxo salt, under the catalytic influence of the... 

The photo-induced process of modification of cellulose and its derivatives was reported by Geacintov and coworkers [67,68]. Thus, acrylonitrile, vinyl acetate, styrene, MMA, and the binary system of styrene and AN were grafted onto cellulose and cellulose derivatives. In... 

Dielectric relaxation measurements of polyethylene grafted with acrylic acid(AA), 2-hydroxyethyl methacrylate (HEMA) and their binary mixture were carried out in a trial to explore the molecular dynamics of the grafted samples [125]. Such measurements provide information about their molecular packing and interaction. It was possible to predict that the binary mixture used yields a random copolymer PE—g—P(AA/HEMA), which is greatly enriched with HEMA. This method of characterization is very interesting and is going to be developed in different polymer/monomer systems. 

Greco et al. [50] studied the effect of the reactive compatibilization technique in ethylene propylene rubber-polyamide-6 blends. Binary blends of polyamide-6-ethylene propylene rubber (EPR) and a ternary blend of polyamide-6-EPR-EPR-g-succinic anhydride were prepared by the melt mixing technique, and the influence of the degree of grafting of (EPR-g-SA) on morphology and mechanical properties of the blends was studied. 

Figure 8 Charpy resilience (R) as a function of test temperature for PA-6 homopolymer and PA-6-EPR binary blends with increasing degree of grafting (DG), 0-0%, -0.6%, A-2.4%, and B-4.5% DG. Source Ref. 61.

An additional contributing factor to the mechanism of the present grafting reaction is the role of radiolytically produced hydrogen atoms. In the radiolysis of binary mixtures of aromatic and aliphatic compounds such as styrene-methanol, the concentration of aromatic strongly influences the G(H2) obtained from the methanol. In the most extensively studied binary mixtures of benzene-methanol (11) and pyridine-methanol (10), it is found that the yield of H atoms is important in determining product yields and types. Small additions (5%) of benzene and pyridine significantly reduce G(H2) from the methanol by scavenging H atoms. Above 5% additive, G(H2) is reduced further, but at a slower rate. These data for benzene-methanol and pyridine-methanol can be extrapolated... 

Further work (10) with acid effects in the radiolysis of binary mixtures such as benzene-methanol and pyridine-methanol indicates that the acid phenomenon is more complicated than the simple H atom model originally developed ( ). These more recent experiments (10) show that whilst increased hydrogen atom yields in the presence of acid enhance the overall grafting yield, other mechanisms also contribute to this acid effect. Thus the acid stability of intermediate radicals (I-III) and also analogous species involving the trunk polymer are important. With radicals (I-III), at low styrene concentrations in methanol, these intermediates (MR-) will predominantly react with other available... 

The simulations and theoretical approaches reveal that the density profile is somewhat lost in the presence of polydispersity [193,202], and special features (including a kink in the profile) are observed for a bimodal chain distribution [195,203 ]. The profiles are flatter for the highest grafting densities, due to the influence of high-order terms. Laradji et al. [204] performed an MC simulation with an off-lattice model that uses the Hamiltonian employed in the SCF calculations (i.e., it only considers binary interactions). The parabolic profiles are... 

Binary composite membranes constitute the chief example of membranes classified under (b) in the introductory section. They include binary polymer blends or block or graft copolymers exhibiting a distinct domain structure, filled or semicrystalline polymers and the like. 

Studies in the grafting of mixed monomers to cellulose have also been reported by Sakurada (113). Binary mixtures studied included butadiene with styrene or with acrylonitrile, and styrene with acrylonitrile. Remarkable increases in rate in the case of mixed monomer similar to those found by RAPSON were found in many cases. For example, about 10% of butadiene increased the grafting yield about ten fold. Similar results were found with the addition of acrylonitrile to butadiene and to styrene. Ternary mixtures of monomers were also investigated by both Rapson (109) and Sakurada (113). The large increases in rate with certain mixtures were interpreted by Sakurada as due to a particular balance of gd effects akin in many ways to popcorn polymerization. The effects were found also with polyvinyl alcohol but not with polyethylene where gel effects would perhaps be less prominent. 

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). 

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