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981.
Jingjing Meng Yushun Zeng Pengfei Chen Jie Zhang Cheng Yao Zheng Fang Pingkai Ouyang Kai Guo 《大分子材料与工程》2020,305(1)
This work outlines an interesting approach to bioepoxy resins from sustainable 2,5‐bis((oxiran‐2‐ylmethoxy)methyl)furan (BOF). The 3,3′‐diamino diphenyl‐sulfone (33DDS) and 4,4′‐diamino diphenyl‐sulfone (44DDS) are employed as hardeners. For comparison, petro‐based networks from diglycidyl ether of bisphenol A (DGEBA) are developed as well. The systematic analyses suggest that the BOF/DDS networks show higher crosslink densities and mechanical properties than DGEBA/DDS thermosets. Remarkably, an attractive multilayer tubular microstructure is fabricated in the BOF/44DDS thermosets, and it greatly enhances the mechanical performance. Apart from that, BOF/DDS composites exhibit excellent flame retardancy. Especially, for BOF/44DDS, the self‐extinguishment happens in 7 s. The fire retardant mechanism confirms that a low heat release rate and heat release capacity as well as a compact char layer occur in the pyrolysis of BOF/DDS. Thus, the BOF/DDS exhibits superior performance over its DGEBA counterparts and meets a wide variety of requirements in engineering. 相似文献
982.
Catalysts for the desulfurization of gasoline samples were synthesized via the immobilization of well-dispersed phosphotungstic acid (HPW) on Mobil composition of matter-twenty-two (MWW) zeolite. Characterization results indicated that these catalysts possess a mesoporous structure with the retention of the Keggin structure of immobilized HPW. Relevant reaction parameters influencing sulfur removal were systematically investigated, including HPW loading, catalyst dosage, temperature, initial S-concentration, molar ratio of oxidant to sulfide (O/S), volume ratio of MeCN to model oil (Ext./oil), and sulfide species. The 40 wt-% HPW/MWW catalyst exhibited the highest catalytic activity with 99.6% dibenzothiophene sulfur removal from prepared samples. The 40 wt-% HPW/MWW catalyst was recycled four times and could be easily regenerated. Finally, as an exploratory study, straight-run-gasoline and fluid catalytic cracking gasoline were employed to accurately evaluate the desulfurization performance of 40 wt-% HPW/MWW. Our research provides new insights into the development and application of catalysts for desulfurization of gasoline. 相似文献
983.
Dachao Tang Zhujun Zeng Yongqing Xia Binghe Chen Shuai Gao Meiwen Cao Shengjie Wang Dongxiang Li 《应用聚合物科学杂志》2020,137(23):48773
In recent years, poly(N-isopropylacrylamide)-based microgels have been emerged as a new thermoresponsive coating for cell/cell sheet harvesting, yet few work reports their effect on cell attachment, morphology, activity, and proliferation in details. In this work, poly(N-isopropylacrylamide-co-styrene) (pNIPAAmSt) microgel was selected as the model to study its density on NIH3T3 cell adhesion, morphology, activity, and detachment. Results showed that 0.5 wt % pNIPAAmSt microgel density leads to more cells adhesion, higher cell activity yet lower cell proliferation. Moreover, cell adhesion location can be well controlled either by manipulating the sub-cellular scale distances between microgels or by fabricating large scale surface patterns of the microgels on higher microgel density. By temperature stimuli, similar ratio cells detached from the microgel density surface from 0.5 to 1.5 wt %. The results in this article are worthy for the application of thermoresponsive microgels in cell regulation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48773. 相似文献
984.
985.
The compatibility of zinc-neutralized sulfonated EPDM (Zn-SEPDM) and its effect on crystallizing behavior of high-density polyethylene (HDPE) as well as the morphology of the blend were studied through wide-angle X-ray diffractomer (WAXD), differential scannign calorimetry (DSC), transition electron micrography.(TEM), scanning electron micrography (SEM), a capillary rheometer, and mechanical property test. The results show that addition of Zn-SEPDM decreases both the melting point and the crystallizing temperature of HDPE. The apparent viscosity of the blend decreases with increasing of shear rate and stress. As Zn-SEPDM content exceeds 20%, Zn-SEPDM in the blend becomes continuous and an abrupt change in impact strength occurs. Owing to the incorporation of ionic groups into EPDM, the strong interaction between the chains make the impact strength of HDPE incredibly increased without sacrificing much of its tensile strength. 相似文献
986.
塑料基TiO2电致变色薄膜制备及性能研究 总被引:1,自引:0,他引:1
采用溶胶-凝胶法分别在镀有ITO透明电极的玻璃和塑料基体上制备了TiO2电致变色薄膜,对比研究了不同基体上溶胶的成膜性及薄膜的电致变色性能.结果表明:在相对湿度低于15%的环境中,采用0.4mol/L的溶胶可以通过多次提拉制得表面光洁的较厚透明TiO2薄膜;随热处理温度的升高,薄膜的电色可逆性变好,循环寿命变大,但离子储存能力下降;塑料基TiO2薄膜与相同条件下制备的玻璃基薄膜具有相似的性能,呈现出较弱的阴极电致变色效应和较强的Li 储存能力,有望用作柔性电致变色器件的对电极. 相似文献
987.
988.
考察了脉冲式气流干燥过程中不同参数对干燥结果的影响。增大固气流量比,可以增大干燥热效率和降低最终产品的湿含量;进口气体温度的升高,能降低最终产品的湿含量,但同时也降低了干燥的热效率。粒径的减小,会使颗粒表面水分蒸发速度上升,从而降低产品的最终湿含量,增加干燥的热效率。 相似文献
989.
部分实心预应力混凝土管桩是一种用于一般工业与民用建筑基础的新型工程桩,其特点是采用工厂预先填芯生产工艺,从而形成部分实心预应力混凝土管桩.施工时采用预应力钢棒作为连接钢筋,并通过六角头穿芯孔螺丝锁定于端板的预应力张拉孔上,保证桩与桩或基础承台的可靠连接.与一般空心PHC管桩相比,能有效减少现场施工工作量、缩短工期、降低... 相似文献
990.