Gebhart, Thomas M. J.; Jehnichen, Dieter; Koschichow, Roman; Müller, Michael; Göbel, Michael; Geske, Vinzenz; Stegelmann, Michael; Gude, Maik
Multi-scale modelling approach to homogenise the mechanical properties of polymeric closed-cell bead foams
The complex mechanical deformation behaviour of closed-cell foams is governed by morphological and physical properties such as cell structure and crystallinity. In this study, the micro-, meso- and macroscopic scale of commercially available bead foam was analysed. Statistical distribution of the cell structure including cell size, wall thickness and shape…
Improving the Hydrolysis Rate of the Renewable Poly(hexamethylene sebacate) Through Copolymerization of a Bis(pyrrolidone)-Based Dicarboxylic Acid
Noordzij, Geert J.; Roy, Manta; Bos, Natasja; Reinartz, Vincent; Wilsens, Carolus H. R. M.
In this work, we report on the synthesis of a series of polyesters based on 1,6-hexanediol, sebacic acid, and N,N’-dimethylene-bis(pyrrolidone-4-carboxylic acid) (BP-C2), of which the latter is derived from renewable itaconic acid and 1,2-ethanediamine. Copolymers with a varying amount of BP-C2 as dicarboxylic acid are synthesized using a melt-polycondensation reaction…
Tailored crystalline order of nascent polyethylene from metallocene supported on confined polystyrene
Wu, Yanjie; Yang, Huaqin; Li, Wei; Mattea, Carlos; Stapf, Siegfried; Zhang, Letian; Ye, Chunlin; Ye, Xiaofeng
Building the desirable superstructure of polyethylene is one of the important topics for developing high value-added products, which brings potential benefits for society and sustainable development. Crystalline order is the ubiquitous superstructure for enhancing mechanical properties of polymeric materials. In this work, polystyrene copolymers (c-PS) are incorporated into pores of…
Facile Route for the Fabrication of Polypropylene Separators for Lithium-Ion Batteries with High Elongation and Strong Puncture Resistance
Kang, Jian; Chen, Dandan; Xiong, Bijin; Zheng, Nan; Yang, Feng; Xiang, Ming; Zheng, Zhuo
A facile route for fabrication of polypropylene separators for lithium-ion batteries with high elongation and strong puncture resistance has been proposed in this work. Polypropylene separators immersed in paraffin wax have been prepared to introduce small molecules into separators. The influence of small molecules on mechanical properties of separators is…
Time resolved alkali silicate decondensation by sodium hydroxide solution
Dupuis, Romain; Rodrigues, Donatien Gomes; Champenois, Jean-Baptiste; Pellenq, Roland; Poulesquen, Arnaud
Silica is by far the chemical compound the most widespread and used around the world: as a raw product in the buildings and roads industry, as concrete, or as a processed product in the manufacture of glass, ceramics or zeolites. In alkali silicate solutions often used to synthesize those…
Local mobility in electrochemically inactive sodium in hard carbon anodes after the first cycle
Jensen, Anders C. S.; Olsson, Emilia; Au, Heather; Alptekin, Hande; Yang, Zhengqiang; Cottrell, Stephen; Yokoyama, Koji; Cai, Qiong; Titirici, Maria-Magdalena; Drew, Alan J.
Sodium ion batteries are a promising alternative to current lithium ion battery technology, providing relatively high capacity and good cycling stability at low cost. Hard carbons are today the anodes of choice but they suffer from poor rate performance and low initial coulombic efficiency. To improve the understanding of the…
Toughening anti-overswelling semicrystalline polymer hydrogels with ultra-small hydrophobic nanoparticles
Meng, Xiaohui; Wu, Teng; Qiu, Dong
Semicrystalline polymer hydrogels (SC-gels) are intrinsically electrolyte tolerant and over-swelling resistant, emerging as promising candidates for applications in solution environments. However, SC-gels with high mechanical strength are usually brittle. In the present work, by introducing ultra-small hydrophobic nanoparticles, highly-stretchable SC-gels (15 times of its original length) with
Morphological Evolution of Tetrachlorinated Perylene Bisimides with Lengthy Alkyl Substituent Polycrystalline Thin Films during Reversible Phase Transitions
Xin, Rui; Wang, Shaojuan; Zeng, Cheng; Ji, Andong; Zhang, Jie; Ren, Zhongjie; Jiang, Wei; Wang, Zhaohui; Yan, Shouke
The phase behavior and related morphological evolution of thin films of lengthy alkyl substituted core-tetrachlorinated perylene bisimide (C18-4ClPBI), a large ?-conjugated molecule, have been studied. It is found that the C18-4ClPBI can exist in two different crystalline phases depending on temperature, which transform reversibly in heating and cooling processes. The…
Transformation from form II to form I accelerated by oriented lamellae in Polybutene-1
Chen, Jinlong; Wang, Binghua; Sun, Taicheng; Xu, Jianwei; Chen, Jingbo; Zhang, Bin
Promoting the transformation from Form II to Form I in polybutene-1 (PB-1) is deemed to be crucial and demanded for commercial applications. The mechanism of phase transition is previously described in terms of thermal or mechanical stress applied between the crystalline and amorphous regions. Here, we find that the structural…
Microstructure Induced Rigidity of Polysiloxane Yielding Hierarchical Self-Assembly of Alkyl Side Chains
Sarkar, Alok; Negi, Lalit Mohan Singh; Lewis, Kenrick M.; Vasimalai, Nagamalai; Gowd, E. Bhoje; Dasgupta, Debarshi
The influence of a backbone microstructure on the side chain crystallization of a comb-like polymer is analyzed systematically using a tailor-made random versus block siloxane copolymer system. While the side alkyl chains of the random siloxane undergo a stepwise orderdisorder (OD) transition to form well-ordered orthorhombic structure at low temperature,…