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This work has investigated two routes of synthesising polymers containing L-histidine using maleimide chemistry; grafting of histidine onto an ethylene-alt-maleic anhydride copolymer and AIBN (azobisisobutyronitrile) initiated radical polymerisation of the monomer maleoyl-L-histidine. The grafting technique and monomer synthesis are utilising the maleimide formation between the primary amine of histidine and maleic anhydride. The reactions are conveniently carried out in one step with good yields. The copolymers containing L-histidine were prepared by reacting L-histidine or L-histidine methyl ester with poly(ethylene-alt maleic anhydride) in DMSO at 50 °C for 8-16 h with 80% yields independent of the degree of substitution. The monomer maleoyl-L-histidine was synthesised by reacting histidine and maleic anhydride in acetic acid and the monomer was subsequently polymerised by AIBN radical initiation in DMSO at 80 °C for 48 h to yield poly(N-histidyl maleimide). The resulting polymer had a different optical rotation ([α] = −11) than the monomer ([α] = +25), which is ascribed to the threo-diisotactic and/or threo-disyndiotactic stereoregularity of the polymer. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The multi-sited phase transfer radical polymerisation of acrylonitrile (AN) with newly synthesized and characterized 1, 4-Bis (tributyl methyl ammonium) benzene dichloride (MPTC) was investigated in K2S2O8 aqueous-organic two phase system at 60 ± 1 °C under nitrogen atmosphere. The role of concentrations of monomer, initiator, catalyst, temperature, acid and ionic strength on the rate of polymerisation (Rp) was ascertained. The order with respect to monomer, initiator and multi-site phase transfer catalyst were found to be 0.5, 1.0 and 0.5, respectively. A suitable kinetic scheme has been proposed to account for experimental observations and its significance. The prepared polymer was characterized by FT-IR and XRD analysis. [ABSTRACT FROM AUTHOR]

The article describes the perhaps most important synthetic access, the so-called macromonomer route to dendronized polymers which are comb polymers with dendrons of varying generations as the teeth. After a brief description of this route in general terms, some recent examples are discussed. The polymerisation mechanisms are either step or chain growth which has considerable impact not only on achievable molar mass and mass distribution but also on the chemical nature of the polymers’ backbone. Even for macromonomers with high generation dendrons, the highest molar mass dendronized polymers presently available are prepared by chain growth procedures. To cite this article: A.D. Schlu¨ter et al., C. R. Chimie 6 (2003). [Copyright &y& Elsevier]