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This study describes the synthesis, the spectroscopic, and the thermal characterization of linear and crosslinked polymers as well as a number of corresponding model compounds, containing Diels–Alder adducts derived from furan and maleimide groups. The thermal reversibility (rDA, DA) of structurally varied model compounds, polymeric and network structures were studied by differential scanning calorimetry, where possible in combination with 1H NMR spectroscopy. It was established that the endo and exo DA stereoisomers show significantly different thermal responses: the rDA of the endo DA‐adducts typically takes place at 20–40 K lower temperatures than that of the corresponding exo DA‐adducts in all cases, with the exception of some aromatic maleimides. Although in situ isomerization was observed to a limited extent and only in some cases, this effect is not expected to influence the thermoremendability of DA‐crosslinked networks being dependent on two separate stereoisomeric rDA steps. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3456–3467, 2010

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The influence of organized media on polymerization reactions results in many cases in interesting morphologies of the polymeric material. In the present study, vesicle bilayers were used as ordered medium for the free radical polymerization of styrene. Cryo-electron microscopy gives evidence that the polymerization induces phase-separation phenomena leading to parachute-like morphologies. On the basis of general knowledge about vesicles and polymerizations in heterogeneous media, explanations for the observed phenomena are given. Bearing in mind that vesicles are outstanding models for membrane mimetic chemistry, it becomes evident that these findings can be relevant to the investigation of, for example, membrane-protein interactions.

Polypropylene (PP)/sepiolite (Sep) nanocomposites are prepared by melt compounding in a miniextruder apparatus. The often used maleic anhydridemodified polypropylene (PP-g-MA) is compared with two custom-made functionalized polymers, PP-acid and the diblock copolymer PP-PEO, with respect to the filler dispersion and filler reinforcement efficiency. For that purpose, morphological and mechanical studies are carried out by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and mechanical tensile tests. In addition, the nanocomposites are characterized by wide-angle X-ray scattering (WAXS) and differential scanning calorimetric (DSC) techniques, to assess the effect of the nanofiller on the crystalline structure of the PP matrix nano-filler. The use of PP-PEO and PP-acid resulted in a better nanofiller dispersion compared with traditional PP-g-MA-modified systems. Sepiolite acts as nucleating agent for the crystallization of PP and seems to lead to an orientation of the a-phase crystals.