Copolymer hydrocarbon-maleic anhydride

The double bond of maleic anhydride may undergo free radical polymerization with the proper initiator. Polymers of maleic anhydride (or copolymers made with another monomer) are commercially available (Polysciences). They consist of a linear hydrocarbon backbone (formed from the polymerization of the vinyl groups) with cyclic anhydrides repeating along the chain. Such polymers are highly reactive toward amine-containing molecules. 

MVE/MAN Copolymem. Various iuol wl grades of polv(melliyl vinyl ether-co-maleic anhydride) (PMVEMA) are available. PMVEMA, supplied as a white, fluffy powder, is soluble in ketones, esters, pyridine, lactams, and aldehydes, and insoluble in aliphatic, aromatic, or halogenated hydrocarbons, as well as in ethyl ether and nitroparaffins. When the copolymer dissolves in water or alcohols, the anhydride group is cleaved, forming the polymers in free acid form or the half-esters of the corresponding alcohol, respectively. 

Through copolymerization there can be made materials with different properties than those of either homopolymer, and thus another dimension is added to the technology. Consider, for example, styrene. Polymerized alone, it gives a good electric insulator that is molded into parts for radios, television sets, and automobiles. Copolymerization with butadiene (30%) adds toughness with acrylonitrile (20-30%) increases resistance to impact and to hydrocarbons with maleic anhydride yields a material that, on hydrolysis, is water-soluble, and is used as a dispersant and sizing agent. The copolymer in which butadiene predominates (75% butadiene, 25% styrene) is an elastomer, and since World War II has been the principal rubber substitute manufactured in the United States. 

Chlorine is virtually absent in the copolymer produced in the azobisisobutyronitrile (AIBN) catalyzed copolymerization of styrene and maleic anhydride in the presence of chloroform or carbon tetrachloride (3, 4), or of p-dioxene and maleic anhydride in the presence of acrylonitrile in chloroform (5). This absence indicates that trichloromethyl radicals generated by the reaction of the chlorinated hydrocarbons with the radicals from AIBN are not incorporated into the polymer chain. Similarly, there is little or no cnlorine in the alternating copolymer that is formed in the copolymerization of styrene and methyl methacrylate in the presence of ethylaluminum sesquichloride (EASC) in the presence of chloroform and carbon tetrachloride, and with or without a peroxide initiator (6). 

PP [or PP copolymer with 20-40 wt% hydrocarbon resin], in the core outer layers from PP, LLDPE, PB, or their blends with 4-15 wt% PP and the intermediate layers from polyolefin-based carboxylic acid or maleic anhydride. 

Foster and Lindt developed models for devolatilization in connection with reactive extrusion (27,28). In later work it has been described that in a reflux flask reactor a significant acceleration of a transesterification reaction could be achieved if a boiling inert hydrocarbon solvent was present (29). The same significant enhancement was found in reactive extrusion with simultaneous devolatilization, during a monoesterification reaction between styrene-maleic anhydride copolymer and alcohol (30). 

Polymeric nonionic surfactants can also be prepared from prepolymerized hydrocarbon backbones. An interesting class of materials already mentioned, alternating copolymers, can be synthesized from polymers of maleic anhydride and styrene, a-olefins, and other interesting molecules. Maleic anhydride has the interesting (and usefid) property that it tends to copolymerize with most other olefins in a regularly alternating manner MA - - O —> (MA-0) , where MA represents the maleic anhydride unit and O, the olefin component. An example of such a syntnesis would be the reaction of maleic anhydride with 1-hexadecene. The resulting polyanhydride can be further reacted with an alcohol, amine, and so on (RXH) to produce a comb polymer. If the teeth of the comb are, for example, short to... 

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