Styrene-butadiene rubber copolymer abbreviation

Abbreviations-. EPDM, ethylene-propylene-diene monomer (a copolymer elastomer) CTBN, carboxy-terminated butadiene nitrile (an elastomer prepolymer) ABS, acrylonitrile-butadiene-styrene (a complex latex structure used both independently and to toughen other polymers) SBR, styrene-butadiene rubber (an elastomer). 

Abbreviations coiX-V] = copolymers of X and Y colX-b-Yl = block copolymers of poly X and poly Y ST = styrene MA = methyl acrylate MMA = methyl methacrylate AN = acrylonitrile BD = butadiene LR (liquid rubbers) = a, cj-polybutadiene-diols and -dicarboxylic acids Cell-Ac = cellulose acetate Cell-N02 = cellulose nitrate. 

Give abbreviated stmctnres of each of the following compounds (a) ( )-l,4-poly-2-methyl-l,3-butadiene [(i )-l,4-poly-isoprene] (b) l,2-poly-2-methyl-l,3-butadiene (1,2-polyiso-prene) (c) 3,4-poly-2-methyl-l,3-butadiene (3,4-polyisoprene) (d) copolymer of 1,3-butadiene and ethenylbenzene (styrene, QH5CH=CH2, SBR, used in automobile tires) (e) copolymer of 1,3-butadiene and propenenitrile (acrylonitrile, CH2=CHCN, latex) (f) copolymer of 2-methyl-1,3-butadiene (isoprene) and 2-methylpropene (butyl rubber, for inner tubes). 

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