Methacrylate polymers degradation

Zhu and co-workers [84] have studied the thermal degradation of a new flame-retardant phosphate methacrylate polymer. Degradation was monitored by in situ Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Raman measurements. The carbon structure of the final char after burning was examined. 

A. Laachachi, E. Leroy, M. Cochez, M. Ferriol, and J. M. Lopez-Cuesta, Use of oxide nanoparticles and organoclays to improve thermal stability and fire retardancy of poly(methyl methacrylate). Polymer Degradation and Stability, 89 (2005), 344-52. 

C. Manzi-Nshuti, J. M. Hossenlopp, and C. A. Wilkie, Fire retardancy of melamine and zinc aluminum layered double hydroxide in poly(methyl methacrylate). Polymer Degradation and Stability, 93 (2008), 1855-63. 

Grassie,N. McNeiU,I.C. and Samson, JJS.R., Degradation of polymer mixtures-Part 10 The thermal degradation of blends of polyacrylonitrile and poly(methyl methacrylate), Polym. Degrad. Stabil., 1 (1), 17-35 (1979). 

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]. 

Methacrylic polymers in general can be easily identified by Py-GC/MS because at temperatures higher than 400°C they degrade by unzipping, a mechanism of depolymerization in which the polymer essentially reverts to monomers [65]. Thus the main pyrolysis product of Elvacite 2044 is BMA. 

In this case, there are too few macroradicals available for reaction because of insufficient polymer degradation. In the disk-type extruder, a higher-stress gradient is achievable, more macroradicals are generated, and intensive cross-linking between polyethylene or highly chlorinated polyethylene and maleic anhydride or methyl methacrylate can be obtained (Heinicke 1984, Zhao et al. 2002, 2003). 

Polymethyl methacrylate (PMMA) degrades under irradiation and becomes more soluble due to main chain scission. The degradation can be greatly reduced by the addition of 10% of various additives, such as aniline, thiourea, or benzoquinone. PMMA is an example of a nongelling polymer it does not form a three-dimensional network structure under irradiation. ... 

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. 

D. Price, K. Pyrah, T.R. Huh, G.J. Milnes, J.R. Ebdon, BJ. Hunt, P. Joseph, and C.S. Konkel, Flame retarding poly(methyl methacrylate) with phosphorus-containing compounds Comparison of an additive with a reactive approach. Polym. Degrad. Stab., 74,441 447 (2001). 

Ebdon, J. R., Price, D., Hunt, B. J., Joseph, P., Gao, F. G., Milnes, G. J., and Cunliffe, L. K., Flame retardance in some polystyrenes and polyfmethyl methacrylate)s with covalently bound phosphorus-containing groups Initial screening experiments and some laser pyrolysis mechanistic studies, Polym. Degrad. Stab., 2000, 69, 267-277. 

Su, S., Jiang, D. D., and Wilkie, C. A. Poly(methyl methacrylate), polypropylene and polyethylene nanocomposite formation by melt blending using novel polymerically-modified clays, Polym. Degrad. Stab. (2004), 83,321-331. 

Gentilhomme A, Cochez M, Ferriol M, Oget N, Mieloszynski JL. Thermal degradation of methyl methacrylate polymers functionalized by phosphorus-containing molecules. Ill Cone calorimeter experiments and investigation of residues. Polym. Degrad. Stab. 2005 88 92-97. 

Inaba, A., Kashiwagi, T., and Brown, J. E. Effects of initial molecular weight on thermal degradation of polyfmethyl methacrylate) Part 1—Model 1. Polymer Degradation and Stability 1988 21 1. 

Degradation of polymers The effect of heat on polymers varies according to the type of polymer under investigation. In an inert atmosphere, polymeric materials react in two distinct ways they either depolymerize or carbonize. For example, poly(methyl methacrylate) may degrade back to the monomer. 

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