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Reversible complexation mediated polymerization (RCMP) was demonstrated in the presence of an aqueous phase using various amine catalysts and monomers to investigate the effect of hydrophobicity of amine catalysts and monomers on the polymerization control of RCMP in aqueous heterogeneous systems. The essential criteria for polymerization control were (i) sufficient hydrophobicity of initiators and catalysts to enable partitioning into monomer phases, (ii) a suitable I2 concentration and temperature for improving polymerization control using long-alkyl chain amine catalysts, and (iii) sufficient monomer hydrophobicity to suppress water solubilization into monomer phase.
The acidolysis, hydroxypropylation and esterification could influence the DSC curve of TG. Among them, the esterification obviously reduced the initial temperature, peak temperature and conclusion temperature.
The 2D WAXD/SAXS data collected using a synchrotron X-ray microbeam technique revealed the details of the lamellar twisting phenomenon of high-density polyethylene spherulites. The molecular mechanics calculation, performed for large aggregation models of alkane chains having bulky head groups or folded polyethylene chains, has successfully reproduced the lamellar twisting pitch of a few μm, as extracted from the X–ray data analysis.
Graphene-doped ZnO nanoplates (G-ZNPs) were incorporated as a reinforcing material into polyvinyl alcohol (PVA) to prepare nanocomposite PVA/G-ZNP hydrogels by forming a network structure of hydrogen and coordination bonding. G-ZNP improves the tensile property, swelling degree and dye adsorption capacity of PVA hydrogel, and also endows the hydrogel with excellent antibacterial properties.
We investigated the hydration behaviors of PEG and PEGylated dendrimer using X-ray diffraction, infrared spectroscopy, and differential scanning calorimetry analysis in the range of −80 °C to 80 °C. At 20% water content, ice crystals were formed and melted during the heating. At 70% water content, however, PEG crystals were formed and melted. In the mixture of the PEGylated dendrimer with 20% water content, ice formation was suppressed. Comparative analyses are important for the evaluation of such eutectic mixtures of PEG compounds and water.
The effects of incorporating poly(d,l-lactide) (PDLLA) and solvent on the stereocomplex (SC) crystallization and homocrystallization of poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) chains were explored using linear one-armed PLLA (1-L)/PDLA (1-D) and linear one-armed PDLLA (1-DL) as an unconstrained system and using four-armed PLLA-b-PDLA (4-L-D) and linear one-armed 1-DL as a constrained system. The dilution effects of PDLLA and solvent enhanced SC crystallization and suppressed homocrystallization, with the exception of the constrained 4-L-D/1-DL blends in the presence of both PDLLA and solvent.
The folding behavior of a 2-dimethylaminoethyl methacrylate oligomer with alternately protonated side chains surrounded by water molecules was evaluated using molecular dynamics simulations in the temperature range of 280–360 K. Radial distribution functions (RDFs) around the geometric center of the oligomer were evaluated; they indicated that protonated amine groups surrounded the aggregating deprotonated amine groups in the globule state. The calculation of RDFs around the geometric center is a highly reliable strategy to evaluate the folding behavior of stimuli-responsive polymer gels during the coil-to-globule transition.