Green Polymer Chemistry and Bio‐based Plastics: Dreams and Reality Tập 214 Số 2 - Trang 159-174 - 2013
Rolf Mülhaupt
AbstractDwindling fossil resources, surging energy demand and global warming stimulate growing demand for renewable polymer products with low carbon footprint. Going well beyond the limited scope of natural polymers, biomass conversion in biorefineries and chemical carbon dioxide fixation are teamed up with highly effective tailoring, processing and recycling of po...... hiện toàn bộ Influence of Type of Initiation on Thiol–Ene “Click” Chemistry Tập 211 Số 1 - Trang 103-110 - 2010
Mustafa Uyğun, Mehmet Atilla Taşdelen, Yusuf Yağcı
AbstractThermally and photochemically initiated thiol–ene click reactions using thiol‐ and allyl‐ end functionalized linear polystyrenes with various enes (allyl bromide, methyl acrylate, and methyl methacrylate) and thiol (3‐mercaptopropionic acid) have been investigated. Allyl‐ and thiol‐end‐capped polystyrenes with controlled molecular weight and low polydispers...... hiện toàn bộ Synthesis, properties and biodegradability of polyesters based on 1,3‐propanediol Tập 195 Số 2 - Trang 793-802 - 1994
Uwe Witt, Rolf‐Joachim Müller, Josef Augusta, Hartmut Widdecke, Wolf‐Dieter Deckwer
AbstractAliphatic homopolyesters and copolyesters based on 1,3‐propanediol and containing terephthalic acid as aromatic compounds and sebacic acid as aliphatic compound were synthesized by condensation in bulk. Intrinsic viscosity and weight‐average molecular weight were measured. Melting temperatures were studied by differential scanning calorimetry. For all polye...... hiện toàn bộ Electrically Insulated Epoxy Nanocomposites Reinforced with Synergistic Core–Shell SiO2@MWCNTs and Montmorillonite Bifillers Tập 218 Số 23 - 2017
Zijian Wu, Sheng Gao, Lei Chen, Dawei Jiang, Qian Shao, Bing Zhang, Zhao-Hui Zhai, Chen Wang, Min Zhao, Yingyi Ma, Xiaohong Zhang, Ling Weng, Mingyan Zhang, Zhanhu Guo
AbstractWith unique physicochemical properties, multiwalled carbon nanotubes (MWCNTs) have enabled major achievement in polymer composites as reinforcing fillers. Nevertheless, high conductivity of raw MWCNTs (R‐MWCNTs) limits their wider applications in certain fields, which require outstanding thermal conductivity, mechanical, and insulation properties simultaneo...... hiện toàn bộ Mechanism of the Formation of Amorphous Gold Nanoparticles within Spherical Polyelectrolyte Brushes Tập 208 Số 14 - Trang 1542-1547 - 2007
Marc Schrinner, Frank Polzer, Yu Mei, Yan Lü, Björn Haupt, Matthias Ballauff, Astrid Göldel, Markus Drechsler, Johannes Preußner, Uwe Glatzel
AbstractWe present a comprehensive investigation on the formation of gold nanoparticles in spherical polyelectrolyte brushes. These colloidal carrier particles consist of a solid polystyrene core onto which long cationic polyelectrolyte chains are grafted. Immersed in water these polyelectrolyte chains can be used to enrich AuCl ions. The metal ions thus confined in the polyelectrolyte layer can be reduced to gold nanoparticles of approximately 1 nm diameter. Cryogenic transmission electron microscopy shows that the Au particles are located near the surface and exhibit a narrow size distribution. Measurements by dynamic light scattering demonstrate that the polyelectrolyte chains are located near the surface of the core particles. This is explained by a crosslinking of the cationic polyelectrolyte chains by the nanoparticles that carry a negative charge. If the Au nanoparticles are removed, the spherical polyelectrolyte brushes re‐expand. High‐resolution electron microscopy together with wide‐angle X‐ray scattering measurements demonstrates that the Au nanoparticles are amorphous. We demonstrate that these Au nanoparticles exhibit catalytic activity for hydrogenation reactions that is slightly below the one of Pt and Pd nanoparticles. hiện toàn bộ
Nuclear magnetic resonance spectroscopic characterization of carboxymethylcellulose Tập 195 Số 5 - Trang 1483-1492 - 1994
Andreas Baar, Werner‐Michael Kulicke, Klaus Szablikowski, R Kiesewetter
AbstractPrevious assignment of the signals in the spectra of carboxymethylcellulose, based on an incremental calculation and hence on low‐molar‐mass model substances, made determination of the partial degree of substitution fundamentally impossible because overlapping of the relevant signals was predicted. However, the methods of acid and enzymatic hydrolysis emplo...... hiện toàn bộ