Xu, Guan; Ding, Lei; Wu, Tong; Xiang, Ming; Yang, Feng
Effect of high molecular weight on pore formation and various properties of microporous membrane used for lithium-ion battery separator
In this article, iPP cast films with high molecular weight in middle layer were prepared to investigate the effect of high molecular weight component on pore formation and mechanical strength. The results of DSC, SEM and 2D-XRD indicated that higher molecular weight and die draw ratio (DDR) would not alter…
Highly Biodegradable and Tough Polylactic Acid–Cellulose Nanocrystal Composite
Muiruri, Joseph K.; Liu, Songlin; Teo, Wern Sze; Kong, Junhua; He, Chaobin
Poly(l-lactide) cellulose nanocrystals-filled nanocomposites were fabricated by blending of cellulose nanocrystals-g-rubber-g-poly(d-lactide) (CNC-rD-PDLA) and commercial PLLA, in which CNC-g-rubber was synthesized by ring opening polymerization (ROP) of d-lactide and a ε-caprolactone mixture to obtain CNC-P(CL-DLA), followed by further polymerization of d-lactide to obtain CNC-rD-PDLA. X-ray…
Bioinspired Polylactide Based on the Multilayer Assembly of Shish-Kebab Structure: A Strategy for Achieving Balanced Performances
Yi, Longfei; Luo, Shanshan; Shen, Jiabin; Guo, Shaoyun; Sue, Hung-Jue
Achieving balanced mechanical performances in a polymer material has long been attractive, but it is still a significant challenge. Herein, a nonadditive strategy was proposed by tailoring the crystalline structure of neat polylactide (PLA) through a layer-multiplying extrusion. Compared with normal PLA, the layer-multiplied material exhibited a 50% increase in…
Effects of Interconnected Polymer Nanopores Leading to Different Degrees of Confined Polymerization
Wang, Kui; Lei, Jinhua; Nie, Heran; Shen, Lu; Chen, Peng; Zhou, Guangyuan
In this study, different degrees of ethylene-confined polymerization (non-confined, slightly confined, and highly confined) are presented in porous polymer microspheres (PPMs) with an interconnected tri-modal pore structure. First, three catalysts, Cp2ZrCl2, Cp2TiCl2, and TiCl4, are attached to the interface of PPMs to form a nano-confined space for ethylene polymerization. Then…
Inter-fibrillar tie chains determined critical stress of large strain cavitation in tensile stretched isotactic polypropylene
Lu, Ying; Lyu, Dong; Xiong, Bijin; Chen, Ran; Men, Yongfeng
Isotactic polypropylene (iPP) samples with pure mesophase, pure α modification, and coexistence of both phases were used to investigate the sudden stress whitening triggered at large strain during stretching. This whitening was caused by the cavities generated in the highly oriented amorphous network. The critical stresses of such cavitation-induced whitening…
High molecular weight poly(butylene succinate-co-furandicarboxylate) with 10mol% of BF unit: Synthesis, crystallization-melting behavior and mechanical properties
Peng, Shuangbao; Bu, Zhiyang; Wu, Linbo; Li, Bo-Geng; Dubois, Philippe
In this study, high molecular weight poly(butylene succinate-co-furandicarboxylate) with 10mol% of butylene furandicarboxylate unit (PBSF10) was synthesized and its crystal structure and crystallization-melting behaviors were investigated by means of WAXD, SAXS, DSC and POM. The tensile properties were also assessed. The crystal structure of PBSF10 is found to be the…
Crystallization of hard segments in MDI/BD-based polyurethanes deformed at elevated temperature and their dependence on the MDI/BD content
Li, Xuke; Lu, Ying; Wang, Hai; Pöselt, Elmar; Eling, Berend; Men, Yongfeng
Morphological variation of thermoplastic polyurethanes (TPUs) with different hard segment contents (HSCs) stretched at 100 °C higher than the Tg of hard domain was monitored by in-situ wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS) techniques. WAXS patterns reveal that the crystalline modification of TPUs with high HSCs transforms from…
Controlling Crystal Microstructure To Minimize Loss in Polymer Dielectrics
Miranda, Daniel F.; Zhang, Shihai; Runt, James
A model semicrystalline polymer, poly(ethylene naphthalate) (PEN), was used to examine how morphological factors inhibit chain segment relaxations that contribute to dielectric loss. This was achieved by manipulating the extent of crystallization and the crystalline microstructure through a combination of annealing and uniaxial drawing and investigating the effects on dielectric…
Structural transformation from shish-kebab crystals to micro-fibrils through hot stretching process of gel-spun ultra-high molecular weight polyethylene fibers with high concentration solution
An, Minfang; Lv, You; Yao, Guibin; Zhang, Li; Wang, Zongbao
Structural evolution of gel-spun ultra-high molecular weight polyethylene fibers with high concentration solution via hot stretching process was investigated by in situ small-angle X-ray scattering, in situ wide-angle X-ray diffraction measurements, scanning electron microscopy, and differential scanning calorimetry. With the increase of stretching strain, the long period continuously increases…
Generating Nanoscopic Patterns in Conductivity within a Poly(3-hexylthiophene) Crystal via Bias-Controlled Scanning Probe Nanolithography
Wang, Binghua; Zhang, Bin; Shen, Changyu; Chen, Jingbo; Reiter, Günter
Generating Nanoscopic Patterns in Conductivity within a Poly(3-hexylthiophene) Crystal via Bias-Controlled Scanning Probe…