@article{HeinzeMangPeteretal.2014, author = {Heinze, Daniel and Mang, Thomas and Peter, Karin and M{\"o}ller, Martin and Weichold, Oliver}, title = {Synthesis of low molecular weight poly(vinyl acetate) and its application as plasticizer}, series = {Journal of applied polymer science}, volume = {131}, journal = {Journal of applied polymer science}, number = {9}, publisher = {Wiley}, address = {New York}, issn = {1097-4628 (E-Journal); 0021-8995 (Print)}, doi = {10.1002/app.40226}, pages = {Article No. 40226}, year = {2014}, abstract = {Poly(vinyl acetate), PVAc, with a degree of polymerization Xn = 10 was prepared by chain-transfer radical polymerization using carbon tetrachloride and used as oligomeric plasticizer for commercial PVAc. However, the chlorinated chain ends cause a low thermal stability requiring mild Cl/H substitution. The product exhibits high thermal stability and excellent melt-compounding properties. Blends of oligomeric and commercial PVAc show single glass transition temperatures which decrease with higher oligomer content and exhibit small negative deviations from Fox' linear additivity rule. This indicates plasticization and miscibility being mainly due to entropic effects. Injection-moulded thick specimens show ductile behaviour at oligomer contents >10 wt \%, while sheets with a thickness of 0.2-0.5 mm appear flexible already at 7.5 wt \%. The oxygen permeability coefficients are an order of magnitude lower than those of low-density polyethylene. Due to the sum of their properties, the plasticized sheets present a promising alternative in the preparation of barrier materials.}, language = {en} } @article{BreuerRaueKirschbaumetal.2015, author = {Breuer, Lars and Raue, Markus and Kirschbaum, M. and Mang, Thomas and Sch{\"o}ning, Michael Josef and Thoelen, R. and Wagner, Torsten}, title = {Light-controllable polymeric material based on temperature-sensitive hydrogels with incorporated graphene oxide}, series = {Physica status solidi (a)}, volume = {212}, journal = {Physica status solidi (a)}, number = {6}, publisher = {Wiley}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.201431944}, pages = {1368 -- 1374}, year = {2015}, abstract = {Poly(N-isopropylacrylamide) (PNIPAAm) hydrogel films with incorporated graphene oxide (GO) were developed and tested as light-stimulated actuators. GO dispersions were synthesized via Hummers method and characterized toward their optical properties and photothermal energy conversion. The hydrogels were prepared by means of photopolymerization. In addition, the influence of GO within the hydrogel network on the lower critical solution temperature (LCST) was investigated by differential scanning calorimetry (DSC). The optical absorbance and the response to illumination were determined as a function of GO concentration for thin hydrogel films. A proof of principle for the stimulation with light was performed.}, language = {en} }