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On the basis of commercially available trimethylolpropane (TMP) three six-membered ring carbonates were prepared, substituted with reactive side groups: a chloroformate (2a), an imidazolyl carbamate (2b) and a phenyl carbonate (2c). Their synthesis and characterizations are described and compared to known ring carbonates with reactive side groups. Starting from 2a-c orthogonal couplers 3a and 3b were synthesized for conversion under mild reaction conditions. In a model reaction 2-azidoethyl 2-N-acetylamino-2-deoxy- -D-glucopyranose and tertbutyl- N-(3-aminopropyl) carbamate were linked with coupler 3a via a 1,3-dipolar cycloaddition and a nucleophilic ring-opening reaction. This coupling principle can be used for the preparation of multifunctional polymers or surface coatings at ambient conditions.

Ethylene - methyl methacrylate block copolymers are semicrystalline polymers that dissolve in organic solvents only at high temperatures. Accordingly, microstructure analysis by solution methods must be conducted at temperatures above 130°C. For the analysis of block copolymers of different compositions several analytical techniques were used, including high-temperature size-exclusion chromatography (SEC), hyphenated SEC-FTIR, and CRYSTAF (crystallisation analysis fractionation). While SEC with refractive index detection indicated a certain multimodality of the samples, SEC coupled with FTIR revealed that the samples were chemically inhomogeneous and may contain homo- and copolymer fractions. The presence of polyethylene and poly(methyl methacrylate) homopolymers in the copolymer samples was confirmed by CRYSTAF analysis, when the total concentration as well as the carbonyl group distribution were monitored separately. Chromatographic separation of the different sample components was achieved when liquid chromatography at critical conditions (LC-CC) was used. For the first time, true high-temperature LC-CC methods were developed operating at a column temperature of 140°C. As the stationary phase, silica gel was used. Suitable mobile phases were binary mixtures of 1,2,4-trichlorobenzene or 1,2- dichlorobenzene with cyclohexanone. Using LC-CC, the samples were separated into the copolymer and the homopolymer fractions.

Atom transfer radical coupling (ATRC) is a method for chain extension of styrene homopolymers prepared by atom transfer radical polymerization (ATRP). This concept is used to produce multiblock copolymers from block copolymers prepared via ATRP of styrene using various macroinitiators. ATRC comprises the reactivation of the dormant species at the chain ends. In the absence of monomer, the active radical species recombine to give chain extension (from polystyrene, PS) or multiblock copolymers (from block copolymers). The application of ATRC to PSblock- poly(bisphenol A carbonate)-block-PS (PS-b-PC-b-PS) was not successful because chain degradation of the PC block occurs. However, poly(phenylene oxide)-block-PS (PPO-b-PS) and PS-b-PPO-b-PS were successfully transformed into tri- and multiblock copolymers by ATRC, although the coupling efficiency is not as high as observed for PS oligomers under similar conditions.

Alternating poly(ester amide)s 6a - e were prepared by polycondensation of α-carboxyl-ω-hydroxyamides 3a - e which were obtained by aminolysis of glutaric anhydride (1) and α,ω-aminoalcohols, H2N-(CH2)x-OH (x = 2 - 6) 2a - e. The polycondensation was performed in dimethylformamide solution using a carbodiimide as activating agent, or in bulk with Bu2Sn(OMe)2, Ti(OBu)4 and Sn(octoate)2 as a catalyst. For the polycondensation in bulk, the influence of catalyst and of temperature on the number-average molecular weight was studied. 1H NMR analyses of the poly(ester amide)s clearly show the alternating microstructure. The poly(ester amide)s from glutaric anhydride and the homologous series of α,ω-aminoalcohols are semicrystalline materials; their melting points show the odd/even effect observed for other poly(ester amide)s.

A-B Di- and B-A-B triblock copolymers with poly(tetramethyleneoxy) (poly(THF)) and poly(tetramethyleneoxycarbonylimino) (poly(TeU)) blocks were prepared by sequential polymerization of tetrahydrofuran (THF) and tetramethyleneurethane (TeU) with the monofunctional initiator methyl trifluormethylsulfonate and the bifunctional initiator trifluoromethanesulfonic acid anhydride, respectively. The block copolymers obtained after purification exhibit a monomodal narrow molecular weight distribution and a uniform microstructure of the two blocks as was deduced from gel permeation chromatography and NMR analysis. The block copolymers are semicrystalline materials with distinct melting points of the poly(THF) and the poly(TeU) domains.