First through fourth generation (G1-G4) dendronized macromonomers, 3, 5, 7, and 9, with a methyleneoxycarbonyl spacer between the polymerizable group and dendritic side chain (dendron) were synthesized, and their polymerization behavior to the corresponding dendronized polymers PG1s, PG2s, PG3s, and PG4s, respectively, was investigated by heating the monomers to 55 degrees C without intentional addition of initiator. This self-induced polymerization is referred to as thermally induced radical polymerization (TRP). The molar masses of PG1s-PG4s were determined by gel permeation chromatography in DMF calibrated to a recently developed G1 dendronized polymer standard (PG1). A comparison of this homologous series' polymerization results with those of an already existing one, which differed only by the lack of this spacer (referred to as PG1-PG4), was made to contribute to the issue of whether short spacers have an effect on polymerization. Several representatives of both series were also used in the first systematic and generation-dependent investigation of these unusual comb polymers' bulk properties. Both structure and dynamics were investigated by DSC, X-ray diffraction, and dynamic mechanical measurements.

Atom transfer radical polymerization (ATRP), reversible addition-fragmentation chain transfer (RAFT) process, and the conventional radical polymerization (RP) were applied to the copolymerization of methyl methacrylate (MMA) and methacrylate-terminated poly(dimethylsiloxane) macromonomer (PDMS-MA). They resulted in PMMA-g-PDMS graft copolymers with various branching and molecular weight distributions. By applying appropriate conditions, ATRP led to homogeneously branched copolymer and RAFT to gradient branched copolymer. The RP process gave heterogeneously branched copolymer with large polydispersity. The structure and mechanical properties in these copolymers were analyzed.

Several non-conventional polyurethane (PU) networks crosslinked with hyperbranched polyester (Boltorn Ò H40) were synthesised with an aim to determine an influence of the PU chain length on molecular relaxations in such systems. The PU chain length was regulated by changing the macrodiol length or by changing the number of the repeating macrodiol/diisocyanate units n. Molecular dynamics were investigated by broadband dielectric spectroscopy and by dynamic mechanical analysis. It was found that the macrodiol length has a strong influence on the glass transition and the a-relaxation, and also on the crystallization. By contrast, the changes of n practically do not affect the molecular relaxations. This effect was explained by the formation of a physical network by hydrogen bonds between urethane groups, controlling the molecular mobility. The rheological measurements have shown, that at temperatures above 150 C, when hydrogen bonds were thermally destroyed, not only macrodiol length but also n had strong influence on the flowing point.

Several polyurethane networks based on hyperbranched polyesters (trade name Boltorn Ò H40) were synthesized. Molecular dynamics in these systems were investigated by means of broadband dielectric spectroscopy and comparatively by dynamic mechanical analysis. Glass transition temperatures were determined by differential scanning calorimetry. It was found that these techniques yield consistent results concerning molecular relaxation processes, however, the dielectric spectroscopy appears to be the most sensitive to show the secondary relaxation processes. The molecular relaxations are much more sensitive to the changes of the chemical character of polyurethane linear links between the hyperbranched centers, than to crosslinking density changed by the length of linear PU chains. The weak influence of the PU chain length on the molecular properties can be explained by the existence of hydrogen bonds forming a physical network, which is more dense and consequently, much stronger than the chemical network in the investigated temperature range.

Several new polyurethane networks based on hyperbranched polyesters (trade name Boltorn) were synthesized to investigate the influence of the hyperbranched crosslinking agent on the molecular dynamics of the linear segments containing urethane groups. For comparison, linear polyurethanes as well as polyurethanes crosslinked with the classical crosslinker trimethylolpropane were prepared. Broadband dielectric spectroscopy, dynamic mechanical analysis, and differential scanning calorimetry yielded consistent results concerning the molecular relaxation processes; however, dielectric spectroscopy appeared to be more sensitive concerning the secondary relaxation processes. In the temperature range up to 1508C, the molecular relaxations were very similar in all the investigated samples, despite considerable structural differences. The weak influence of the crosslinking on the molecular properties could be explained by the existence of hydrogen bonds forming a physical network, which was very dense in this temperature range in comparison with the chemical crosslinks and therefore dominated the molecular mobility in all the investigated systems. This hypothesis was confirmed by rheological measurements performed at temperatures above 1508C, when the hydrogen bonds should be thermally destroyed. At these temperatures, the effect of crosslinking was manifested by a strong shift of the flowing point: in the linear polyurethanes, this point occurred at much higher frequencies (and lower temperatures) than in the crosslinked analogues.

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A general strategy for the preparation of well-defined diblock copolymers combining a random cascade-branched dendritic (i.e., hyperbranched) and a linear block has been developed. The strategy is based on a linear poly(styrene-b-butadiene) (PS-b-PB) diblock copolymer with high molecular weight PS block and short, functional 1,2-PB block, prepared by conventional anionic polymerization. The functional PB block is used for the grafting of branched AB2-type carbosilane monomers, resulting in the attachment of a hyperbranched structure to the backbone. Slow addition of the methyldi(undecenyl)silane monomers using Karstedt's catalyst permits control of the molecular weight of the hyperbranched block, resulting in high molecular weight linear-hyperbranched diblock copolymers. Molecular weights of the block copolymers ranged between 72 800 and 106 400 g/mol for M n, and polydispersity M̄ w/M̄ n was low (typically below 1.1), as predicted by theory for slow monomer addition. Morphological studies by TEM, AFM, and SAXS on these systems demonstrate that various microdomain structures typical for microphase-separated block copolymers can be obtained upon increasing the size of the hyperbranched block with respect to the linear one, despite the strong architectural asymmetry of the linear-hyperbranched macromolecules. However, due to the hyperbranched structure and the crowding of the interface, an asymmetry of the phase diagram is observed. The linear-hyperbranched PS520-b-[PB47-hb-PCSi142] sample with 49 wt % of the hyperbranched component displayed the most unusual morphological behavior

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