Functionalization of an amorphous ethylene‐propylene copolymer, EPM, has been performed by means of homogeneous grafting reactions of unsaturated molecules such as dibutylmaleate, diethylfumarate, itaconic anhydride, and maleic anhydride, initiated by free radicals. Dicumylperoxide and dibenzoylperoxide have been used as a free radical source and their efficiency has been compared. A different reactivity of the unsaturated molecules has been evidenced. The influence of the nature of the solvent on the functionalization degree has been investigated, revealing a noticeable effect of the solvent either on the amounts of grafted molecules or on the secondary reactions which lead to partial degradation of the functionalized EPM chains.

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New formulations of rubber toughening agents for difunctional and tetrafunctional commercial epoxies are attempted, on the basis of their increased thermal stability compared with classical unsaturated elastomers. Quite satisfactory results are obtained where a block copolymer of polydimethylsiloxane and polyoxyethylene elastomer or a functionalized poly (1 -butene) in difunctional epoxy are used. On the other hand, poor results are obtained when the same elastomers are employed in tetrafunctional epoxies. A tentative explanation is given on the basis of the different networks obtained in the two matrix systems.

Base functionalization of saturated ethylene-propylene rubbers (EPR) was performed either by means of the radical grafting of 2-(dimethylamino)ethyl methacrylate onto EPR or by the reaction of a succinic anhydride grafted EPR with N,N-dimethylethylenediamine. Differences in the structure of the grafted molecules and in their thermal stability are also reported. An investigation is made on the reactivity of EPR having tertiary amino pendant groups toward acid functionalized EPR leading to gelation.

synopsisPolyamides from n-alkylmalonic acids and linear aliphatic diamines, with paraffinic side chains of 3-18 carbon atoms, were prepared by melt polycondensation or by lowtemperature interfacial polycondensation and were characterized by infrared, differential scanning calorimetry (DSC), and x-ray diffraction techniques. Firsborder transitions were found in the range of 130-21OoC, depending on the number of carbon atoms in the side chain. The x-ray diffraction indicated substantially amorphous systems for polyamides with 8-18 carbon atoms in the side chain. However, longrange order arises in these polymers from a solid-state structure in which polyamide and hydrocarbon layers having partially disordered chain conformations alternate.