Synthesis of polyglutarimides from p(methyl methacrylate) and cyclohexylamine. I. Influence of working conditions on imidization reaction

Abstract

Over the last 50 years methacrylic polymers, especially poly(methyl methacrylate) (PMMA), have reached a noteworthy place in world polymer production. However, for special applications that require thermal properties, polycarbonates take the place of PMMA because of the latter's low glass transition temperature (T g ) of 105°C. The aminolysis reaction of PMMA with cyclohexylamine in xylene was studied to obtain a polyglutarimide exhibiting higher T g values. The mechanism involving aminolysis and further amidization of ester groups was correlated with the experimental characterization of all the species created during the reaction. Poly(N-cyclohexylacrylamide) and polyglutarimide (prepared from this precursor) were prepared in order to determine the special characteristics of these model compounds by FTIR. This method abled the quantification of ester, amide, acid, and imide groups. This aminolysis reaction was optimized (190-250°C; ratio of constituents, 0.5: 3) by spectroscopically following the different groups and monitoring the increase of the T g . Poly(N-cyclohexyl glutarimide) (65%) containing amide groups (25%) and acid groups (10%) presents a T g value of 195°C.