Styrene/methyl methacrylate copolymer grafted onto

Transparent, Impact-Resistant, Styrene/ Methyl Methacrylate Copolymer Grafted onto Polybutadiene... 

Better control of grafting and less homopolymer formation is achievable in ionic reactions than can be obtained in free-radical reactions. Anionic grafting via backbone initiation has been demonstrated (22) with caprolacteim on macromolecular ester sites of styrene/methyl methacrylate copolymers. Cationic grafting of isobutylene onto poly(vinyl chloride) with the aid of aluminum alkyl has been carried out by J. P. Kennedy (23). 

This technique was developed, for the first time, at Brooklyn Polytechnic Institute, where hydroperoxides, resulting from the thermal oxidation of a vinyl polymer, were used to initiate the polymerization of vinyl monomers. The grafting of styrene, methyl methacrylate, or vinyl chloride onto poly-a-olefins was realized by this method. The thermal oxidation mechanism was shown to involve the formation of hydroperoxides, which decompose to a number of oxygenated functional groups, not necessarily leading to a grafted copolymer. 

The same procedure can be employed to make well defined comb-like polymers Living polystyrene can be grafted onto a partially chloromethylated polystyrene89 146), or onto a random copolymer of styrene and methyl methacrylate containing less than 10% of the latter monomer I48). 

The MABS copolymers are prepared by dissolving or dispersing polybuiadiene rubber in a methyl methacrylate—acrylonitrile—styrene monomer mixture. MBS polymers are prepared by grafting methyl methacrylate and styrene onto a styrene—butadiene rubber in an emulsion process. The product is a two-phase polymer useful as an impact modifier for rigid polytvinyl chloride). 

Acres and Dalton (1963b) studied the graft and/or block copolymeri-zation of methyl methacrylate onto irradiated polystyrene latex and styrene onto irradiated poly(methyl methacrylate) latex. A number of experimental variables and conditions that give good yields were investigated. It was difficult to separate the copolymers from the homopolymers but it was clear that good yields of nonrandom copolymers were indeed obtained. 

ABS-type resins are used as impact modifiers for PVC, but the resultant blend has insufficient transparency for application in clear bottles. Transparency can be obtained by grafting PMMA onto crosslinked PBD (5) or poly (butyl acrylate) (6) which has been previously grafted onto PS (Diagram 4). In this case the PMMA branch is compatible with PVC by virtue of its solubility parameter, and optical clarity results from suitable component ratios in the graft copolymer so that the refractive index matches that of PVC. The desired results are not obtained if a copolymer of methyl methacrylate and styrene is... 

Y. Amagi, M. Ohya, Z. Shiiki, and H. Yusa, PVC Blended with Cross-linked Graft Copolymers of Styrene and Methyl Methacrylate onto a Butadiene Polymer, U.S. Pat. 3,775,514 (1973). MBS resins in latex form. Triple IPN in latex form. Clear, impact-resistant PVC. 

Aerdts AM, Theelen S JC, Smith TMC, German AL. Grafting of styrene and methyl-methacrylate concurrently onto polybutadiene in semicontinuous emulsion processes and determination of copolymer microstructure. Polymer 1994 35 1648-1653. 

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