Manfred Hartmann

Synthesis and Properties of Polyanhydrides Containing Urethane Bonds in the Main Chain

Abstract Polyanhydrides containing urethane linkages in the main chain have been synthesized from bis(4-carboxyphenyl-amino-carbonyloxy) alkanes and oxyalkanes by melt polycondensation of the corresponding acetic mixed anhydrides. Weight-average molecular weights up to 27,000 were obtained. All polymers have been characterized by 1H-NMR and IR spectroscopy as well as by TG analysis. The dicarboxylic acid monomers were prepared by reaction of 4-aminobenzoic acid with suitable bis(chloroformate)s. Hydrolysis of the synthesized polyanhydrides (pH 7.4; 37°C) proceeds with cleavage of anhydride bonds and maintenance of urethane linkages to give nearly constant degradation rates. Comparative hydrolysis studies including poly(amide-anhydride)s and poly(esteranhydride)s having analogous structures are described. The release of 4-nitroanisole as a drug model from a polyanhydride matrix followed the polymer degradation to a large extent.

Polymeric Nitrofuran Derivatives. I. Radical-Initiated Homo- and Copolymerization of 5-Nitrofurfuryl Methacrylate

Abstract The radical homopolymerization of 5-nitrofurfuryl methacrylate (NFMA) and the copolymerization of NFMA with methyl methacrylate and various vinyl monomers, respectively, have been studied in dimethylformamide at 65°C. NFMA and poly(NFMA) have been characterized by 1H-NMR, IR, and UV spectroscopy. The influence of polymerization conditions on monomer conversion and on the molecular weight of the polymers obtained has been investigated. The thermal behavior of the polymers obtained has been studied by TGA and DSC analysis.

Vinyl Polymerization Initiated by Reducing Compounds of Transition Metals. XI. Two-step Selective Graft Copolymerization

Abstract Grafting of methyl methacrylate onto poly(methyl-4-vinylbenzyl-sulfoxide-co-trichloroethyl methacrylate) is initiated by molybdenum (III) chloride in ethylene chloride. In a second step the obtained graft copolymers are grafted with styrene in the presence of chromium(II) acetate and morpholinocyclohexene in dimethylformamide. By this stepwise selective graft copolymerization technique, polymers can be tailored to give the required properties.

Polymeric Nitrofuran Derivatives. II. Chemical Modification of Functionalized Resins with Nitrofuran Derivatives

Abstract Polymeric nitrofuran derivatives have been synthesized by chemical modification of macroporous styrene-divinylbenzene copolymers with low molecular weight nitrofurans. The 5-nitrofuryl groups are covalently attached to the polymeric carrier by azomethine, ester, N-alkyl, and sulfamide links, respectively. Comparative hydrolysis studies and biological tests of the modified resins suggested that the polymeric carrier-bound nitrofurans are antimicrobially active. The polymeric nitrofurans have been characterized by IR and “C-solid-NMR spectroscopy”.