Other polymers of acrylic acid derivatives

Some results on thermal stability and thermal decomposition products of other acrylic acid derivatives including poly(a-chloro-acrylonitrile), poly(a-phenyl acrylonitrile), and poly(acryloyl chloride) as reported in literature are given in Table 6.7.17 [6]. 

The thermal decomposition of poly(methacrylic acid) starts at about 200° when it eliminates water and some monomer, leaving a residue of poly(methacrylic anhydride) [116]. Some decarboxylation also is noticed at lower temperatures. At higher temperatures the decomposition is more complex [117]. The water elimination process has an activation energy of 40.5 kcal mol and the fragmentation of the anhydride an activation energy of 37.4 kcal mol [118]. 

Polymers with saturated carbon chain backbone 

The salts of poly(methacrylic acid) with Na, Li, K and Cs (CAS for Na salt 25086-62-8) decompose at approximately 350°, whereas the Mg and other alkaline earth metal salts decompose at 500°. The NH4 salt decomposes somewhat differently with elimination of NH3, H2O, and other fragments, at higher temperatures (500° C) forming some isocyanic acid and HCN [119], Some results on poly(methacrylic acid) thermal decomposition as reported in literature are given in Table 6.7.18 [6]. 

Polymer poly(methacrylic acid ammonium salt) 

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