Yi, Longfei; Luo, Shanshan; Shen, Jiabin; Guo, Shaoyun; Sue, Hung-Jue
Bioinspired Polylactide Based on the Multilayer Assembly of Shish-Kebab Structure: A Strategy for Achieving Balanced Performances
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…
Scalable, anisotropic transparent paper directly from wood for light management in solar cells
Jia, Chao; Li, Tian; Chen, Chaoji; Dai, Jiaqi; Kierzewski, Iain Michael; Song, Jianwei; Li, Yiju; Yang, Chunpeng; Wang, Chengwei; Hu, Liangbing
The growing demand for flexible electronics and solar energy conversion devices has fueled a search for high-quality paper-based materials with excellent mechanical flexibility and optical properties such as high transparency and haze. Despite the tremendous efforts have been dedicated to developing paper-based materials with high transparency or high haze, challenges…
3D Printing of Liquid Crystal Elastomeric Actuators with Spatially Programed Nematic Order
Kotikian, Arda; Truby, Ryan L.; Boley, John William; White, Timothy J.; Lewis, Jennifer A.
Liquid crystal elastomers (LCEs) are soft materials capable of large, reversible shape changes, which may find potential application as artificial muscles, soft robots, and dynamic functional architectures. Here, the design and additive manufacturing of LCE actuators (LCEAs) with spatially programed nematic order that exhibit large, reversible, and repeatable contraction with…
Cavitation in Poly(4-methyl-1-pentene) during Tensile Deformation
Chen, Ran; Lu, Ying; Jiang, Zhiyong; Men, Yongfeng
The poly(4-methyl-1-pentene) sample was used to investigate the cavitation-induced stress-whitening phenomenon during stretching at different temperatures via the ultrasmall-angle X-ray scattering technique. Two modes of cavitation were found that mode I cavitation activated around yield point followed by mode II cavitation generated in highly oriented state. The critical strain for…
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…
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…
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…
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…
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…
Anisotropic nanoparticles as templates for the crystalline structure of an injection-molded isotactic polypropylene/TiO2 nanocomposite
Zhang, Peng; Kraus, Tobias
We study the molecular origins of anisotropy in a semicrystalline polymer nanocomposite that is caused by aligned, elongated filler nanoparticles. Our study is based on spatially resolved 2D WAXS/SAXS data that indicates the arrangement of molecules, lamellae, and filler particles in the composite. Isotactic polypropylene (IPP) samples filled with anisotropic…