Abstract. An investigation was made of grafting trans-ethylene-1,2-dicarboxylic acid (TEDA) onto metallocene-linear low-density polyethylene (mLLDPE) and low-density polyethylene (LDPE) in the course of reactive extrusion. The initiator was 1,3-bis-(tert-butyl-peroxyisopropyl)benzene. The graft efficiency of TEDA has been shown to increase with increasing initiator concentration, irrespective of polyethylene type. The graft values for LDPE were higher than for mLLDPE over the initiator concentration range (0.05 to 0.4 wt%). The rheological properties of mLLDPE were found to undergo more tangible changes during functionalization than those of LDPE. These changes were caused by side reactions, mainly macromolecular crosslinking. It has been established that some carboxyl groups get transformed to anhydride groups in the grafted product. The concentration of end double bonds reduces, but intramolecular unsaturation in both polyethylenes increases. Data are presented on thermal and stress-strain (mechanical) properties of virgin and functionalized polymers, as well as rheological and viscoelastic properties of their melts.

Distinctive features of free-radical grafting of trans-ethylene-1,2-dicarboxylic acid (TEDA) onto macromolecules of molten ethylene-vinyl acetate copolymer (EVA) in the course of reactive extrusion have been investigated along with structure, mechanical characteristics, and high-elastic properties of molten functionalized products (EVA-g-TEDA). It is shown that EVA-g-TEDA yield depends on both the peroxide initiator concentration and content of vinyl acetate units in the copolymer molecular structure. At functionalization, acid grafting is accompanied by secondary reactions of macromolecular degradation and crosslinking. With a low-peroxide initiator concentration (0.1 wt %), degradation prevails; with a higher (0.3 wt %) concentration, crosslinking of macromolecules prevails. It is reported that monomers being grafted attach mostly over secondary carbon atoms in the polymer chain. EVA-g-TEDA appears to have a less perfect crystal structure with a lower-melting temperature and crystallinity as against the starting polymer. The functionalized products display enhanced rigidity and lower deformability in comparison with the initial copolymer. Variations in the swelling ratio and melt strength of EVA-g-TEDA depend on the course of competing secondary processes of macromolecular degradation and crosslinking.

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The reaction of carboethoxycarbene with styrene and p-substituted styrenes in the conditions of thermocatalytic decomposition of ethyl diazoacetate has been studied. It has been shown that the substituents in the investigated styrenes have an essential effect on the activity of the double bond with respect to carboethoxy¬¬carbene. It has been established as a result of the investigation that the substituents in the para- position of styrene influence essentially on the activity of the double bond with respect to carboethoxycarbene. It has been revealed that carboethoxycarbene is connected to the double bond of styrene and p-styrenes practically without formation of by products. As a result of the reaction, 2-phenyl and 2-p-substituted phenyl-1-ethoxycarbonyl cyclopropane (1–4) as a mixture of cis- and trans- isomers at a ratio of~ (30:70) with the predominant formation of a trans-isomer has been obtained. The composition and structure of the synthesized compounds have been established. It has been revealed that all synthesized cyclopropane-containing compounds show the various biologically active properties. In addition, the compounds 9–12 can be used as a modifier and diluent for epoxy resin ED-20

The radical copolymerization of of (p-vinylphenyl)cyclopropyl chlorocinnamate with styrene has been studied. The new cyclopropane-containing photosensitive copolymer has been prepared. The composition and structure of the synthesized copolymer have been established, the constant values of relative activity of monomers have been determined and the parameters Q-e have been calculated. The dependence of photosensitivity on composition of copolymer has been revealed.

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