Methacrylonitrile copolymerization

Another concern, is the potential reactivity of 10 as a transfer agent under polymerization conditions (see 3.3.1.1.4).103 Tetramethylsuccinonitrile (9) appears to be essentially inert under polymerization conditions. However, the compound is reported to be toxic and may be a problem in polymers used in food contact applications.1" 30 Methacrylonitrile (MAN) formed by disproportionation readily copolymerizes.7"34 The copolymerized MAN may affect the thermal stability of polymers. A suggestion103 that copolymerized MAN may be a "weak link" in PS initiated with AIBN has been disputed.14... 

Copolymerization of butadiene with another monomer such as acrylonitrile, methacrylonitrile, styrene, or methyl vinyl ketone increases perceptibly the proportion of 1,4 units at the expense of 1,2. The ratio of cis to trans is not materially altered, however. One is obliged to conclude that the co-monomer shows a greater preference for addition to the terminal carbon (i.e., to carbon 4) of the resonating chain radical than does the butadiene Foster and... 

Block copolymerization was carried out in the bulk polymerization of St using 18 as the polymeric iniferter. The block copolymer was isolated with 63-72 % yield by solvent extraction. In contrast with the polymerization of MMA with 6, the St polymerization with 18 as the polymeric iniferter does not proceed via the livingradical polymerization mechanism,because the co-chain end of the block copolymer 19 in Eq. (22) has the penta-substituted ethane structure, of which the C-C bond will dissociate less frequently than the C-C bond of hexa-substituted ethanes, e.g., the co-chain end of 18. This result agrees with the fact that the polymerization of St with 6 does not proceed through a living radical polymerization mechanism. Therefore, 18 is suitably used for the block copolymerization of 1,1-diubstituted ethylenes such as methacrylonitrile and alkyl methacrylates [83]. 

A minor reaction of 2-cyano-2-propyl radicals is disproportionation to methacrylonitrile and isobutyronitrile [Moad et al., 1984 Starnes et al., 1984]. This presents a complication for polymerizations carried out to high conversions where the methacrylonitrile concentration is significant since methacrylonitrile undergoes copolymerization with many monomers. 

The incorporation of small percentages (<10%) of 3-oximino-2-butanone methacrylate (4) into poly(methyl methacrylate) (PMMA) (Scheme I) results in a four fold increase in polymer sensitivity in the range of 230-260 nm flO.l 11. Presumably, the moderately labile N-O bond is induced to cleave, leading to decarboxylation and main chain scission (Scheme II). The sensitivity is further enhanced by the addition of external sensitizers. Also, preliminary results indicated that terpolymerization with methacrylonitrile would effect an additional increase. These results complement those of Stillwagon (12) who had previously shown that copolymerization of methyl methacrylate with methacrylonitrile increased the polymer s sensitivity to electron beam irradiation. The mole fraction of the comonomers was kept low in order to insure retention of the high resolution properties of PMMA (3.41. 

In an effort to improve PMMA s photosensitivity further, methyl methacrylate has been copolymerized with higher percentages of the a-keto-oxime methacrylate and terpolymerized with varying amounts of methacrylonitrile. The resulting effects on resist properties, e.g., sensitivity, contrast and resolution, and plasma resistance, are reported here. The terpolymers are up to 85 times more sensitive than PMMA, and retain its high resolution characteristics. 

Table 7. Block copolymerization of methacrylonitrile (MAN) with the living prepolymer of methyl methacrylate (MMA) (2) in the presence of methylaluminum bis(2,6-di-ferf-butyl-4-methylphenolate) (3e) ... 

One of the first detailed studies on these systems was that of Beaman (26), who showed that methacrylonitrile polymerizes by an anionic chain mechanism when treated with various bases, including Na in liquid ammonia at —75° C. He noted also that low molecular weight polymers are obtained from reaction of acrylonitrile with butylmagnesium bromide. Foster (56) extended the liquid ammonia method to copolymerization studies in which acrylonitrile was combined with styrene, with methyl methacrylate and with vinyl butyl sulfone. Satisfactory data were obtained only with the sulfone, in which case there was some tendency for alternation. 

However, the ratio 22/ 21 is the reactivity ratio f2 for copolymerization of acrylonitrile with methacrylonitrile, so that... 

Gindin, Abkin, and Medvedev (21) observed several of the characteristics of copolymerizations involving charge transfer intermediates in the benzoyl peroxide-catalyzed copolymerization of butadiene with acrylonitrile and methacrylonitrile. Irrespective of the initial concentrations, polymerization ceased when one of the components was consumed. The butadiene-acrylonitrile copolymer had a 67% alternating structure, while the butadiene-methacrylonitrile copolymer had an 80% alternating structure. 

When 0.3 mol fraction methacrylonitrile is copolymerized with styrene in a radical reaction, what is the average length of sequences of each monomer in the copolymer ... 

Methacrylonitrile is a slow polymerizing monomer under conditions of CCT, and it yields oligomer with a double-bond end group similar to methacrylates (eq 40). The resulting oligomeric products have a stronger tendency to copolymerize with additional monomer and thus be incorporated into subsequent polymer chains than do MMA oligomers.139... 

Excited states and energy migration by way of excitons have been studied in random copolymers of acenaphthylene (ACN) with acrylonitrile (AN), methacrylonitrile (MAN) and 2-vinyl napthalene (2VN). Also ACN was copolymerized with vinyl acetate and hydrolyzed to give free hydroxyl groups. 

Polystyrene formed at 60 or 85% conversion was found to contain methacrylonitrile units, which should have been introduced by the copolymerization of methacrylonitrile formed through disproportionation of the primary radicals of AIBN. 

Transfer to monomer is an important process in the radical polymerization of vinyl chloride so that the number of initiator fragment in a polymer chain is less than unity. For example, poly(vinyl chloride)s prepared with AIBN in 1,2-dichloroethane at 40°C were found to contain 0.17 0.34 AIBN fragments per chain from the 13C NMR analysis of the polymer reduced with Bu3SnH. The polymers also contained a CN group in the chain (0.025 0.12 per chain), suggesting the copolymerization of methacrylonitrile which was formed in situ or admitted as an impurity in the starting AIBN.79... 

The catalyzed graft copolymerization of styrene-methyl methacry-late-EASC and a-methylstyrene-methacrylonitrile-EASC onto nitrile rubber in solution is shown in Table XII. In addition, grafting has been done on ethylene-propylene copolymers, polybutadiene, acrylic ester copolymers, and other polymers containing labile hydrogen atoms. 

It was shown many years ago that if some methacrylic acid is copolymerized with methacrylonitrile, the discolouration reaction... 

Only a small percent of styrene copolymers reported in the literature achieved industrial importance. Some of the interesting copolymers of styrene that were reported but not utilized commercially are copolymers with various unsaturated nitriles. This includes vinvlidine cyanide, fumaronitrile, malononitrile, methacrylonitrile, acrylonitrile, and cinnamonitrile. Often, copolymerization of styrene with nitriles yields copolymers with higher heat distortion temperature, higher tensiles, better craze resistance, and higher percent elongation. 

Other Anionic Carboxyiate Monomers. The anionic carboxylate monomers 8A and 9A, prepared by the Ritter reaction involving acrylonitrile or methacrylonitrile and 3,3-dimethylacrylic acid have been copolymerized in the sodium salt form to yield calcium-tolerant copoljnners with utility in enhanced oil recovery (145-148). Monomer 8A, for example, has been copol5unerized with 7A... 

Styrene (3.0 M) is copolymerized with methacrylonitrile (1.5 M) in benzene solution by adding benzoyl peroxide to a concentration of 0.1 M and heating to 60° C. Calculate for the polymer initially formed (a) composition of the copolymer, (b) probability of forming styrene and methacrylonitrile sequences that are 3 units long, (c) average sequence lengths of styrene and methacrylonitrile in the copolymer, and (d) the run number of the copolymer. [Given fi = 2 = 0.25 at 60° C.]... 

K. R. Sharma, Methacrylonitrile as Termonomer in Alphamethylstyrene and Acrylonitrile Multicomponent Copolymerization, AIChE Spring National Meeting, New Orleans, LA, March 30th-April 3rd, 2003. 

Random copolymers based on acrylonitrile and methacrylonitrile with ethyl a-acetoxyacrylate [69] were synthesized by radical copolymerization. The microstructure of the resulting copolymers was characterized by C NMR spectroscopy, and some reactivity ratios could be assessed. In addition, copolymers based on methyl vinylidene cyanide (MVCN) and vinyl acetate [70], styrene [71], or substituted styrene also exhibit interesting dielectric behavior [72]. 

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