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Supramolecular gels consisting of trivalent polyisobutylene and bivalent poly(ethylene oxide) are generated. Strong hydrogen bonding interactions, affixed to the end‐group moieties of the respective polymers (binding constantKassn= 105M–1), serve as molecular glue, leading to the formation of weak gels. Two different gels were prepared: one, with a short telechelic poly(ethylene glycol) (PEG) segment (gel A), and one with a longer PEG segment (number‐average molecular weight Mn= 2000 g mol–1) (gel B). Both gels show a significant increase in viscosity upon mixing of the two polymeric components, with a lag time of several minutes, indicative of nucleation mechanisms as the formation principle. However, only gel A displays classical gel‐like behavior, with a loss modulus G′ larger than the storage modulus G″ after formation. Both gels display microphase‐separated behavior with a spacing between 4–5 nm as probed via small‐angle X‐ray scattering (SAXS) and transmission electron microscopy (TEM) measurements. The incorporation of magnetic nanoparticles (Fe2O3; radius r= 3.5 nm) is successfully achieved, generating new magnetic gels with strongly thermoresponsive properties, displaying a strong temperature‐dependent release profile of included dye molecules. Magnetic measurements indicate a superparamagnetic behavior of the incorporated nanoparticles, prospecting the application as magneto‐sensitive delivery gels for pharmaceutical purposes.

Amphiphilic AB, A¹A²B, and A2B block copolymers, where A = polyisobutylene, B = poly(methyl vinyl ether), and the superscripts denote molecular weight asymmetry, with constant molecular weight and composition have been synthesized by living cationic polymerization. The influence of architecture on aqueous micellar properties of these block copolymers were investigated in the temperature range 20−30 °C by fluorescence spectroscopy and static and dynamic light scattering (SLS and DLS). The critical micelle concentration (cmc) measured at 23 °C increased in the order A2B < A¹A²B < AB. The partition equilibrium constants, Kv of pyrene, characteristic of hydrophobicity, increased in the opposite order of cmc. The hydrodynamic radii (Rh) and aggregation numbers (Nagg) of micelles remained approximately constant in the whole temperature range for A¹A²B and A2B and below 25 °C for AB. At ~25 °C, however, there was a sudden increase in both Rh and Nagg for AB. Below 25 °C both Rh and Nagg increased in the order AB < A¹A²B < A2B. The particle size distribution for all block copolymers remained narrow in the whole temperature range. The results are discussed in terms of possible morphologies.

The reaction between lactic acid and diphenylmethane diisocyanate was studied by ¹H NMR, ¹³C NMR, and matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy. The structure of the oligomers formed was also investigated and supported by using the postsource decay method. Analysis of the products revealed that, besides linear chain copolymer formation, branching and homooligomerization of lactic acid also took place. A mechanism is suggested for the cooligomerization processes.

The carbocationic polymerization of n-butyl vinyl ether (BVE) using the new LiAlH4/AlCl3 initiating system is reported. The polymerizations were carried out in diethyl ether (Et2O), and in a mixture of diethyl ether and dichloromethane (1:1 v/v) at various temperatures, and the kinetics of the polymerizations was studied. The rate constants, the temperature dependence of the rate constants, and the kinetic order of the reactants were determined. The end groups of the polymers were characterized by ¹H NMR and MALDI-TOF MS methods. Three different interconvertible end groups, i.e., heteroacetal, homoacetal, and aldehyde, were observed. The tacticity of the polymers formed was determined by ¹³C NMR. On the basis of detailed kinetic and structural investigations, a direct initiation mechanism for the polymerization is proposed.

The decarboxylation upon oligomerization of propylene carbonate in the presence of the bisphenol A/KHCO3 initiating system was studied by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Five different series of peaks appeared in the MALDI-TOF MS spectra of the oligomerization mixture. In addition to the chain-extension reaction with the propylene oxide units, the oligomers of all of the propylene oxide units and oligomers containing carbonate end groups condensed. The product of the oligomerization reaction was hydrolyzed under alkaline conditions. It was found that hydrolyzed oligomers do not carry carbonate groups. The results of the MS studies agreed well with those obtained by ¹H and ¹³C NMR spectroscopies and size-exclusion chromatography (SEC). On the basis of the results of the present investigation, a mechanism for the oligomerization is also proposed.

The melt polycondensation of d,l-lactic acid was studied by the MALDI-TOF MS method at temperatures ranging from 100 to 220 °C. At low temperature, i.e., up to 120 °C, linear, and at higher temperature both linear and cyclic oligomers were formed. The ring−chain equilibrium was investigated in detail and the concentration-based equilibrium constants (Kx) and their dependence on the degree of polycondensation and on the temperature were determined. It was also found that the molecular size distribution of the linear chain oligomers obeys to “the most probable distribution”. A detailed investigation also showed that the ring size distribution of the cyclic oligomers follows the Jacobson-Stockmayer theory.

Characterization of polyisobutylene (PIB)−polybutylene terephthalate (PBT) multiblock copolymers by thermally stimulated discharge (TSD) current and dynamic mechanical analysis (DMA) methods is described. Both the length of the PIB segments (2200−10000 g/mol), and the overall composition (30−80 wt %) of the multiblock copolymers were varied. Both methods support the block structure of the multiblock copolymers investigated. Despite the apolar nature of the PIB segments, they proved to be detectable by the TSD method. The relaxation times and the mobility of the chain length were also determined.

The effect of light on the Bray−Liebhafsky oscillatory reaction was studied at 55 °C. It was found that both the induction time and period decreased with the increasing light intensity, and at a critical value of intensity, dependent on the initial concentration of the reactants, oscillation disappeared. The reaction scheme proposed by Schmitz was extended with a direct reaction of I2 with H2O2. By taking into account the latter reaction, the oscillations were numerically calculated and good agreements with the experimental data were found.

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