Butadiene-acrylonitrile-methacrylic acid-terpolymer

Rao and co-workers [62] applied Py-GC and C-NMR to the determination of sequence distribution of butadiene (B) - acrylonitrile (A) - methacrylic acid (M) terpolymers. Sequence distribution was described in terms of six triads (BBB, ABA, ABB, BBA, MBR and AMB) and found to vary with the mode of addition of methacrylic acid monomer. 

NMR data were found to be in good agreement with a mechanism of polymerisation in which methacrylic acid is preferentially involved in initiation reactions by a 

Rao and co-workers [62] classified into (I) triads containing butadiene (b), (II) triads containing butadiene (B) and acrylonitrile (A) and (III) triads containing B, A and M units. 

These workers discuss, under separate headings, the following types of triads BB, ABA, ABB, BBA, MBM, MBB and BBM under olefinic carbon resonances and BBB, ABA, ABB triads under nitrile carbon resonances. 

The main conclusions that can be drawn from the C-NMR studies of the terpolymers can be summarised as follows  

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Organic peroxides are used in the polymer industry as thermal sources of free radicals. They are used primarily to initiate the polymerisation and copolymerisation of vinyl and diene monomers, eg, ethylene, vinyl chloride, styrene, acryUc acid and esters, methacrylic acid and esters, vinyl acetate, acrylonitrile, and butadiene (see Initiators). They ate also used to cute or cross-link resins, eg, unsaturated polyester—styrene blends, thermoplastics such as polyethylene, elastomers such as ethylene—propylene copolymers and terpolymers and ethylene—vinyl acetate copolymer, and mbbets such as siUcone mbbet and styrene-butadiene mbbet. 

Third Monomers. In order to achieve certain property improvements, nitrile mbber producers add a third monomer to the emulsion polymerization process. When methacrylic acid is added to the polymer stmcture, a carboxylated nitrile mbber with greatly enhanced abrasion properties is achieved (9). Carboxylated nitrile mbber carries the ASTM designation of XNBR. Cross-linking monomers, eg, divinylbenzene or ethylene glycol dimethacrylate, produce precross-linked mbbers with low nerve and die swell. To avoid extraction losses of antioxidant as a result of contact with fluids duriag service, grades of NBR are available that have utilized a special third monomer that contains an antioxidant moiety (10). FiaaHy, terpolymers prepared from 1,3-butadiene, acrylonitrile, and isoprene are also commercially available. 

Acrylic resin Acrylonitrilefbutadiene/styrene copolymer Bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite Butadiene/acrylonitrile copolymer EthyleneA/A copolymer Methoxyethyl acrylate Methyl methacrylate butadiene styrene terpolymer Polyethylene elastomer, chlorinated 2-Propenoic acid, 2-methylmethyl ester, polymer with 1,3-butadiene and butyl 2-propenoate impact modifier, PVC rigid EVA/PVC graft polymer impact modifier, recycled polyamides EPDM, maleated impact modifier, thermoplastics Butadiene/acrylonitrile copolymer impact strength modifier PEG-6 trimethylolpropane impact-resistance lights Polyester carbonate resin impact-resistance, lights Polyester carbonate resin impeller... 

Orientations in elongated mbbers are sometimes regular to the extent that there is local crystallization of individual chain segments (e.g., in natural rubber). X-ray diffraction patterns of such samples are very similar to those obtained from stretched fibers. The following synthetic polymers are of technical relevance as mbbers poly(acrylic ester)s, polybutadienes, polyisoprenes, polychloroprenes, butadiene/styrene copolymers, styrene/butadiene/styrene tri-block-copolymers (also hydrogenated), butadiene/acrylonitrile copolymers (also hydrogenated), ethylene/propylene co- and terpolymers (with non-conjugated dienes (e.g., ethylidene norbomene)), ethylene/vinyl acetate copolymers, ethyl-ene/methacrylic acid copolymers (ionomers), polyisobutylene (and copolymers with isoprene), chlorinated polyethylenes, chlorosulfonated polyethylenes, polyurethanes, silicones, poly(fluoro alkylene)s, poly(alkylene sulfide)s. 

Olefin copolymer Styrene acrylonitrile copolymer Amylonitrile butadiene styrene terpolymer Thermoplastic olefin elastomer Ethyl methacryl acid copolymer ... 

Py-GC-MS has been used to characterise elastomers including natural rubber, butyl rubber, polychloroprene and acrylonitrile-butadiene copolymer [91]. Other copolymers that have been investigated include 1-octene-l-decene-l-dodecane terpolymer [92], acrylic-acid methacrylic acid [39],styrene-butadiene[93-95],styrene-isoprene [54], ethylene-vinyl acetate [96], polyisopropenyl cyclohexane - -methyl styrene [57], vinyl pyrrolidine- methacryloxysilicone [97], ethylene-carbon monoxide [98], acrylic copolymers [99], 1-vinyl-2-pyrrolidine - l-vinyl-3-methylimidoazolium chloride [100], acrylonitrile-butadiene-styrene [101], acetone-furfural [102] and styrene-acrylonitrile [103]. 

Styrene/acrylonitrile copolymers are used for crockery, machine components, and monofilaments. They are made less breakable by the addition of l,4-ci5-poly(butadiene) (ABS polymer). ABS polymers are sensitive to sunlight and acid (weathering in exterior use), so for these purposes ASA polymers are more suitable, i.e., terpolymers of acrylic ester, styrene, and acrylonitrile. Terpolymers of methyl methacrylate, butadiene, and styrene (MBS polymers) are transparent, in contrast to ABS polymers. 

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