Degradation methacrylate copolymers

Radical copolymerization is used in the manufacturing of random copolymers of acrylamide with vinyl monomers. Anionic copolymers are obtained by copolymerization of acrylamide with acrylic, methacrylic, maleic, fu-maric, styrenesulfonic, 2-acrylamide-2-methylpro-panesulfonic acids and its salts, etc., as well as by hydrolysis and sulfomethylation of polyacrylamide Cationic copolymers are obtained by copolymerization of acrylamide with jV-dialkylaminoalkyl acrylates and methacrylates, l,2-dimethyl-5-vinylpyridinum sulfate, etc. or by postreactions of polyacrylamide (the Mannich reaction and Hofmann degradation). Nonionic copolymers are obtained by copolymerization of acrylamide with acrylates, methacrylates, styrene derivatives, acrylonitrile, etc. Copolymerization methods are the same as the polymerization of acrylamide. 

A study was made of the thermal degradation behaviour of PS foams used as patterns in the lost foam process for metal casting. The data indicated that the thermal degradation of the pattern had a strong effect on mould filling and casting quality. The use of other types of foam such as PE, PP, PMMA and styrene-methyl methacrylate copolymers to overcome problems encountered with PS foam patterns is discussed. 7 refs. 

To some extent, the stability of VDC polymers is dependent on tire nature of the comonomer present. Copolymers with acrylates degrade slowly. Copolymers with acrylonitrile or methacrylate undergo degradation more readily. 

Copolymer. The appearence and properties of a particular copolymer obtained depended to a large degree on the type of monomer with which the copolymer was prepared. LS-(methyl acrylate) and LS-(methyl methacrylate) copolymers were brownish amorphous solids. The former was rubbery and moderately hard and the latter was plastic like and harder than the former. At room temperature, both were insoluble in ordinary solvents and quickly swelled in water to about six times in volume. At elevated temperature, the lignin backbone of these two copolymers could be degraded through acid or alkaline hydrolysis. 

Poly(acrylates) and (alkyl acrylates). - Structured nanopore films of poly(styrene-block-methyl methacrylate) copolymers have been made with controlled spectral sensitivity, such that each block is sensitive to a specific degradation wavelength. In copolymers of 2,2,2-trifluoroethyl methacrylate with vinyl ethers, the photosensitivity is controlled by the vinyl ether units. Photodegradation occurs at the tertiary positions of the ether units followed by lactone formation and chain scission processes. Furthermore, the fluorinated side chains have been found to inhibit cyclization reactions. 

Table 1.1 Reported techniques to selectively degrade one copolymer block. Poly(styrene) PS, poly (dimethylsiloxane) PDMS, poly(ethyleneoxide) PEO, poly(isoprene) PI. poly(lactic acid) PLA. poly(methyl methacrylate) PMMA, poly(vinylpyridine) PVP, 3-pentadecylphenol PDP...

Morris MJ, Striegel AM (2012) The effect of styrene-methyl methacrylate monomeric arrangement on the ultrasonic degradation of copolymers. Polym Degrad Stab 97 2185-2194... 

In a study of the flame retardance of styrene-methyl methacrylate copolymer with covalently bound pyrocatechol-vinyl phosphate, diethyl p-vinyl benzyl phosphonate, or di(2-phenyl ethyl phosphonate) groups. Ebdon and co-workers [23] obtained data on their decomposition behaviour. This was achieved by reducing the rate of liberation of flammable methyl methacrylate monomer during combustion. Possible mechanisms for these processes are suggested. Other methacrylate copolymers which have been the subject of thermal degradation studies include PMMA-N-methylmaleimide-styrene [24] and PMMA-ethylene vinyl acetate [25-27]. 

Amino methacrylate copolymer Eudragit EPO 56 1. Processing at 100 °C 2. Degradation onset is > 200 °C 3. Low Tg can limit stability... 

A variety of studies have been made on copolym of styrene. They include the kinetics of degradation of styrene-alkyl methacrylate copolymers the effect... 

Over the last few years a number of applications on the analysis of olefin copolymers have been published that make use of the LC-Transform system. These include the SEC-FTIR analysis of ethylene/vinyl acetate copolymers [117], ethylene/ methyl methacrylate copolymers [118, 119], ethylene/styrene copolymers [120], HOPE and PP [121]. A number of studies used SEC-FTIR for monitoring the thermo-oxidative degradation of polyolefins [122-126] and a combination of TREE and SEC-FTIR to investigate the complex structure of olefin copolymers [127,128]. 

Vinu, R., Madras, G. Photocatalytic degradation of methyl methacrylate copolymers. Polym. Degrad. Stab. 93, 1440-1449 (2008)... 

Poly(methyl methacrylate)-Ws poly(styrene) Ambient to 500 Polymers degrade separately without interaction to give same products as polymers degraded separately copolymers and mixtures of the same molar compositions can be distinguished by degradation behavior 141... 

Because the polymer degrades before melting, polyacrylonitrile is commonly formed into fibers via a wet spinning process. The precursor is actually a copolymer of acrylonitrile and other monomer(s) which are added to control the oxidation rate and lower the glass transition temperature of the material. Common copolymers include vinyl acetate, methyl acrylate, methyl methacrylate, acrylic acid, itaconic acid, and methacrylic acid [1,2]. 

Grassie, N., "Recent Work on the Thermal Degradation of Acrylate and Methacrylate Homopolymers and Copolymers", Pure and Appl, Chem., 1972, 30, 119-134. 

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