Dietmar Stadermann

Structural investigations on low molecular weight polybutadienes and the corresponding epoxides

Abstract Structural investigations of low molecular weight polybutadienes and derived epoxides have been made by 13C-NMR. It is possible to attribute the signals of methylene and methine carbon atoms to different diads and triads of the polybutadienes as well as of the epoxides. Methods for the quantitative determination of the epoxide content have been compared.

Synthesis of oxidation stabilized cyclopentadiene polymers via cationic copolymerization with 4-isopropenylphenol

SummaryA method is described to improve the oxidation stability of cyclopentadiene co- and terpolymers via cationic polymerization using 4-isopropenylphenols as polymerizable comonomers. The efficiency of these phenols depends on their part in the copolymer and on the number and size of their alkyl groups.

Synthesis and Photoinitiated Cationic Polymerization of Substituted 2‐Cyclopropyl‐4‐methylene‐1,3‐dioxolanes

The synthesis of substituted 2-cyclopropyl-4-methylene-1,3-dioxolanes 6a-c is described. Photoinitiated cationic polymerization at ambient temperatures in bulk and in solution was investigated using (η 5 -2,4-cyclopentadiene-1-yl)[1,2,3,4,5,6-η] (1-methylethyl) benzene)iron(II) hexafluorophosphate (Irgacure 261, I-1) and ditolyliodonium hexafluoro-phosphate (I-2). Upon irradiation a single ring-opening polymerziation occured within 4 min leading to polyether ketones 6a-c with number average molecular weights M n between 5000 and 33 600 g/mol. No ring-opening polymerization of the cyclopropane ring could be detected. A volume shrinkage of about 6.4% was found.

Photopolymerization of exo-methylene-1,3-dioxolane with bisphenol-A-diglycidylether and methyl methacrylate using photoinitiators

The copolymerization of 2-exo-methylene-4-phenyl, 3-dioxolane with bisphenol-A-diglycidylether and methyl methacrylate using a cationic and a radical initiator is described. The structure of the polymers is elucidated by NMR and IR spectroscopy. Using a cationic photoinitiator the dioxolane structure is maintained in the copolymer and remaining oxirane structures from the bisphenol-A-diglycidylether can be proved. Surprisingly, no complete ring-opening of the dioxolane takes place in the presence of a radical initiator leading to statistical copolymers with methyl methacrylate.

Polymerizable derivatives of (+)-1(S)-p-nitrophenyl-2(S)-amino-propane-1, 3-diol

Template molecules have been used to generate cavities in polymer materials. If chiral template molecules are used, then it is to be expected that the prepared cavities will also be chiral. An attempt has been made to convert (+)-1(S)-p-nitrophenyl-2(S)-amino-propane-1,3-diol, a by-product in the synthesis of chloroamphenicol, into polymerizable derivatives and to incorporate these derivatives into polymers. Preferred conformations of the monomers were calculated by means of the cosmos force field. The results are compared with those of the spectroscopic characterization of the substances.