Styrene, graft copolymers with methacrylate

II. B polyethylene glycol, ethylene oxide, polystyrene, diisocyanates (urethanes), polyvinylchloride, chloroprene, THF, diglycolide, dilac-tide, <5-valerolactone, substituted e-caprolactones, 4-vinyl anisole, styrene, methyl methacrylate, and vinyl acetate. In addition to these species, many copolymers have been prepared from oligomers of PCL. In particular, a variety of polyester-urethanes have been synthesized from hydroxy-terminated PCL, some of which have achieved commercial status (9). Graft copolymers with acrylic acid, acrylonitrile, and styrene have been prepared using PCL as the backbone polymer (60). 

The ozonization method has been extended to the most varied polymer/monomer systems, such as polybutadiene-03 with acrylamide, methyl methacrylate or styrene, cellulose-03 with styrene or acrylonitrile (127), starch-03 with styrene (126). In this last case the formation of some homopolystyrene as side-product has been mentionned by the authors. The starch-styrene graft copolymers are claimed to be good emulsifiers for water-oil suspensions. 

Comparison of Methyl Methacrylate-Butadiene-Styrene with Acrylonitrile-Butadiene—Styrene Graft Copolymers... 

Weather-resistant ABS can be obtained either by the incorporation of EVAc [Fukushima and Mitarai, 1971], or by replacing PB with EPDM, to obtain AES [Wefer, 1984, 1985, 1988]. Alternatively, blends of SAN with maleated EPDM and CPE may be used [JCim et al., 1994]. However, the non-weatherable styrenics are frequentiy prepared by dissolving an elastomer in methyl methacrylate, and either styrene or a-methylstyrene, then polymerizing them into methyl methacrylate-butadiene-styrene graft copolymers... 

A second approach is the copolymerization of vinyl, or methacryloyl group containing backbone chain of poly(si 1sesqui-oxanes) with vinyl monomers such as styrene, methyl methacrylate, and acrylonitrile by a radical initiator. At low concentration of monomers ( less than 10 vjt% ), soluble styrene-grafted copolymers have been indeed obtained. 

Recently, several other aminopolymers were synthesized for the NCA polymerization. Ichie and coworkers used copolymers of styrene-vinyl benzylamine and methyl methacrylate-vinyl benzylamine for NCA polymerization to study the kinetics of NCA polymerization with macroinitiators. 2 The polymerization was Ist-order with respect to monomer concentration and was much faster in nitrobenzene than in dioxane or THF. Kiba patented a new system for NCA polymerization with the different aminopolymers [38] produced according to Scheme 5. He also claimed the ester exchange reaction of the resulting graft copolymer with ethylene cyanohydrin over p-toluene sulfonic acid. 

Figure 9.17 Plot of log [i ]M versus retention volume for various polymers, showing how different systems are represented by a single calibration curve when data are represented in this manner. The polymers used include linear and branched polystyrene, poly(methyl methacrylate), poly(vinyl chloride), poly(phenyl siloxane), polybutadiene, and branched, block, and graft copolymers of styrene and methyl methacrylate. [From Z. Grubisec, P. Rempp, and H. Benoit, Polym. Lett. 5 753 (1967), used with permission of Wiley.]...

A waterborne system for container coatings was developed based on a graft copolymerization of an advanced epoxy resin and an acryHc (52). The acryhc-vinyl monomers are grafted onto preformed epoxy resins in the presence of a free-radical initiator grafting occurs mainly at the methylene group of the aHphatic backbone on the epoxy resin. The polymeric product is a mixture of methacrylic acid—styrene copolymer, soHd epoxy resin, and graft copolymer of the unsaturated monomers onto the epoxy resin backbone. It is dispersible in water upon neutralization with an amine before cure with an amino—formaldehyde resin. 

Recently it has been shown that anionic functionalization techniques can be applied to the synthesis of macromonomers — macromolecular monomers — i.e. linear polymers fitted at chain end with a polymerizable unsaturation, most commonly styrene or methacrylic ester 69 71). These species in turn provide easy access to graft copolymers upon radical copolymerization with vinylic or acrylic monomers. 

In our own research, the functional termination of the living siloxanolate with a chlorosilane functional methacrylate leading to siloxane macromonomers with number average molecular weights from 1000 to 20,000 g/mole has been emphasized. Methacrylic and styrenic monomers were then copolymerized with these macromonomers to produce graft copolymers where the styrenic or acrylic monomers comprise the backbone, and the siloxane chains are pendant as grafts as depicted in Scheme 1. Copolymers were prepared with siloxane contents from 5 to 50 weight percent. 

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