An, Minfang; Lv, You; Yao, Guibin; Zhang, Li; Wang, Zongbao
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
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…
Effects of oxidation on the physicochemical properties of polyunsaturated lipid membranes
Parra-Ortiz, Elisa; Browning, Kathryn L.; Damgaard, Liv S. E.; Nordström, Randi; Micciulla, Samantha; Bucciarelli, Saskia; Malmsten, Martin
The exposure of biological membranes to reactive oxygen species (ROS) plays an important role in many pathological conditions such as inflammation, infection, or sepsis. ROS also modulate signaling processes and produce markers for damaged tissue. Lipid peroxidation, mainly affecting polyunsaturated phospholipids, results in a complex mixture of oxidized products, which…
Adduct modified nano-clay mineral dispersed polystyrene nanocomposites as advanced corrosion resistance coatings for aluminum alloys
Raju, Annu; Lakshmi, V.; Vishnu Prataap, R. K.; Resmi, V. G.; Rajan, T. P. D.; Pavithran, C.; Prasad, V. S.; Mohan, S.
The present investigation is on processing of a series of clay polystyrene nanocomposite (CPS) coatings containing different adduct modified montmorillonite (Mt) for corrosion resistance coating applications. The corrosion properties were studied using potentiodynamic and electrochemical impedance spectroscopy measurements in 3.5wt% aqueous NaCl electrolyte. The CPS coatings offered enhanced
Amino-functionalized breath-figure cavities in polystyrene–alumina hybrid films: effect of particle concentration and dispersion
V, Lakshmi; Raju, Annu; G, Resmi V.; Pancrecious, Jerin K.; D, Rajan T. P.; C, Pavithran
We report the formation of breath-figure (BF) patterns with amino-functionalized cavities in a BF incompatible polystyrene (PS) by incorporating functionalized alumina nanoparticles. The particles were amphiphilic-modified and the modifier ratio was regulated to achieve a specific hydrophobic/hydrophilic balance of the particles. The influence of the physical and chemical properties of…
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…
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…
Characterization of multi-scale structure and thermal properties of Indica rice starch with different amylose contents
Li, Zhihang; Kong, Xiangli; Zhou, Xianrong; Zhong, Kui; Zhou, Sumei; Liu, Xingxun
Fully understanding the relationship between multi-scale structure and thermal properties of rice starch is important for starch-based food processing. Multi-scale structures of Indica rice starch were studied from molecules to aggregation structure. Gel-permeation chromatography (GPC) and high-performance anion-exchange chromatography (HPAEC) both show that the amylopectin from debranched rice…
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…
Effects of calcination and activation conditions on ordered mesoporous carbon supported iron catalysts for production of lower olefins from synthesis gas
Oschatz, M.; Deelen, T. W. van; Weber, J. L.; Lamme, W. S.; Wang, G.; Goderis, B.; Verkinderen, O.; Dugulan, A. I.; Jong, K. P. de
Lower C2–C4 olefins are important commodity chemicals usually produced by steam cracking of naphtha or fluid catalytic cracking of vacuum gas oil. The Fischer–Tropsch synthesis of lower olefins (FTO) with iron-based catalysts uses synthesis gas as an alternative feedstock. Nanostructured carbon materials are widely applied as supports for the iron…