Аннотация:Free radical initiated polymerization of methyl methacrylate containing1–15 wt% of dissolved polyimide is studied by a calorimetric method. It isshown that polyimide (up to 10 wt%) addition leads to a shifting of the initialautoacceleration and initial autoretardation conversions to lower conversionvalues than those for polymerization of plain methyl methacrylate. It is statedthat polyimide macromolecules do not create additional initiation reactioncentres, but may take part in chain transfer and/or termination reactionsduring methyl methacrylate polymerization. Besides polyimides some otheraromatic polymers, namely polyesters, polyamides, poly(ether ether ketone)sand poly(phthalide)s, have been used in similar processes. The new copolymersobtained differ in properties (solubility, thermal resistance, etc) compared tocorresponding polymer components.