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使用聚乙烯吡咯烷酮(PVP)和聚乙二醇(PEG)作为钝化剂对铜纳米颗粒进行原位包覆制备了PVP/PEG/Cu复合纳米粒子(CuNP),将其作为导热增强剂引入到PEG中制备了CuNP/PEG固-液相变储能材料(PCMs),并通过FTIR、XRD、DSC以及TGA等表征了CuNP/PEG固-液PCMs的结构及热性能。利用纳米粒子表面的PVP与PEG之间的氢键和空间位阻效应,以及PVP对铜核的保护作用,赋予了铜纳米粒子在PCMs中优异的分散稳定性。结果表明,CuNP的引入能够显著提高复合相变储能材料的导热能力,并能够作为晶核加速材料的结晶行为。当纳米粒子的质量分数为5%时,CuNP/PEG固-液PCMs的相变焓值为157.0 J/g,体系的储热速率、放热速率和结晶速率与纯PEG相比分别提高了34.09%、31.45%和53.33%。 相似文献
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新型丙烯-乙烯共聚物增韧聚丙烯的研究 总被引:1,自引:0,他引:1
丙烯-乙烯共聚物Vistamaxx(VM)是一种丙烯摩尔含量占70%以上的新型弹性体。用VM增韧聚丙烯(PP),考察了PP/VM共混物的力学性能、微观形态结构以及结晶性能,并与乙烯-辛烯共聚物(POE)与PP的共混体系进行了对比。结果表明,常温下VM增韧效果优于POE,PP/VM体系拉伸性能优于PP/POE体系;VM在PP中表现出比POE更好的分散性;VM具有与PP相同的晶型,VM的加入细化了PP的晶粒。 相似文献
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聚氨酯型固-固相变储能材料的合成与性能表征 总被引:1,自引:0,他引:1
采用两步溶液聚合法以DMF为溶剂,PEG、MDI、BDO为原料合成了一种聚氨酯型高分子固-固相变储能材料,运用傅立叶红外光谱(FTIR)、差示扫描量热仪(DSC)、偏光显微镜(POM)对该种材料进行结构分析和性能表征,对其相变行为和相变机理进行初步探讨。结果表明,所合成的PUPCM相变焓较大,热性能稳定。相变过程中不出现液体,是一种具有较大使用价值和发展前途的高分子固-固相变储能材料。 相似文献
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以含二氮杂萘联苯结构的聚芳醚砜酮PPESK(Tg263—305℃)为膜材料,以干-湿相转化法制备中空纤维基膜,采用内涂法涂覆聚乙烯基吡咯烷酮(PVP),并配合Ag+,制备了促进输送中空纤维复合膜。研究了复合膜聚电解质涂敷时间、2次涂层、不同银盐以及不同过渡金属离子等对复合膜丙烯/丙烷分离性能的影响。实验结果表明.室温下,n(Ag+):n(C=O)=1:1,涂敷时间为10min时,复合膜对丙烯/丙烷的分离性最好,PVP/AgNO3体系分离系数为3.98,PVP/AgBF4体系的分离系数为5.69。经过2次涂敷后,PVP/AgNO3体系的分离系数升高至4.20,PVP/Ag-BF4体系的分离系数升高至10.78。由此可见,相同条件下,AgNO3的促进传递效果明显低于AgBF4。 相似文献
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采用接枝共聚法将聚乙二醇(PEG)接枝到聚乙烯醇(PVA)主链上,得到了系列性能稳定的PEG/PVA高分子固固相转变材料,利用DSC法对PEG在受限状态下等温结晶及结晶后的熔融行为进行了研究。结果表明:PEG和共聚体系的Avrami指数n在2左右,说明结晶生长方式是二维生长,速率常数Z随温度升高而减小,样品的成核属非均相依热成核方式。结晶后的等温熔融行为表明PEG出现熔融双峰,共聚体系只显示一个与PEG低温峰相对应的吸收峰,该峰的高温侧出现肩峰,且随T0升高而变得明显。 相似文献
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在导电高分子家族中,聚(3,4-二氧乙基噻吩)(PEDOT)由于具有高的电导率、环境稳定性、透明性以及良好的成膜性等优异性能而广泛地应用于有机电致发光器件、太阳能电池、防静电、电致变色器件、传感器等领域.本论文研究了绝缘高分子聚乙二醇(PEG)和乙二醇、一缩二乙二醇等有机极性溶剂提高PEDOT/PSS(聚苯乙烯磺酸钠)电导率的机理,并通过改变稳定剂、掺杂剂等因素制备了具有不同结构和性能的PEDOT胶体颗粒以及PEDOT/PMMA(聚甲基丙烯酸酯)复合微球,取得了以下主要的创新性结果。 相似文献
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Bin‐Yi Chen Yuan‐Sheng Wang Hao‐Yang Mi Peng Yu Tai‐Rong Kuang Xiang‐Fang Peng Jing‐Song Wen 《应用聚合物科学杂志》2014,131(23)
In this study, we prepared poly(lactic acid) (PLA)/poly(ethylene glycol) (PEG)/sodium chloride (NaCl) blends by melt blending with a triple‐screw dynamic extruder. The effects of PEG on the thermal property, mechanical property, and morphology of blends were investigated in detail. It was found that the incorporation of PEG and NaCl significantly improved the crystallization rate, elongation at break, surface adhesion, and reduced viscoelasticity of PLA. The blends were further batch‐foamed at different temperatures with supercritical carbon dioxide to study the foaming properties. The results of PLA/PEG/NaCl (50 : 10 : 40 wt %) composites after foaming and particle leaching revealed that an interconnected bimodal porous scaffold with the highest porosity of 89% could be achieved. Furthermore, the addition of PEG can significantly reduce the water contact angle so as to enhance the wetting ability of the scaffolds. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41181. 相似文献
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以机械共混法制备亲水性聚对苯二甲酸乙二醇酯(PET)共混材料,并通过接触角测定仪、差示扫描量热仪(DSC)和电子万能材料试验机等对共混材料的亲水性能、热性能和力学性能等进行研究与分析。结果表明,亲水处理剂聚乙二醇(PEG)、聚丙烯酸钠(PAAS)、聚乙烯吡咯烷酮(PVP)均能改善PET的亲水性能,影响PET的结晶性能,但亲水处理剂对PET的力学性能影响较小,其中PET/PEG共混材料的亲水性最优;随着PEG含量的增加,PET/PEG共混材料的亲水性先逐渐增强,当PEG含量高于5%后,共混材料的亲水性变化很小;且PET的结晶度随着PEG的加入呈现先增大后减小的趋势。 相似文献
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Phase separation behavior of cocamidopropyl betaine/water/polyethylene glycol (PEG) system was studied. The effects of concentration and molecular weight of PEG on the phase separation behavior were investigated. Clouding occurred when the con-centration of PEG was large enough in the betaine aqueous solution, and the concentration of PEG at cloud point decreased with the increase of PEG molecular weight for a constant betaine concentration. The bottom phase was the PEG-rich phase, and the upper phase was the betaine-rich phase. The volumetric ratio of PEG-rich phase to betaine-rich phase, at the same difference between the PEG concentration and the one at the cloud point, 61508;Ccp (0.1 g8226;ml-1), decreased as the PEG molecular weight increased and approached 1 for higher PEG molecular weight (about 20000), which was similar to the typical aqueous two-phase system. This volumetric ratio depended on the initial PEG concentration, but independent of PEG molecular weight. The concentration ratio of betaine to PEG in both phases depended on the 61508;Ccp, independent of PEG molecular weight. 相似文献
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Wenhao Zhang Binyi Chen Haibin Zhao Peng Yu Dajiong Fu Jinsong Wen Xiangfang Peng 《应用聚合物科学杂志》2013,130(5):3066-3073
Both poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG) are biodegradable polymers, blending PLA with PEG is expected to toughen PLA matrix while maintaining its biodegradability. In this study, PLA/PEG blends in different ratios were prepared through triple‐screw extruder, and the foaming behavior was investigated using supercritical carbon dioxide as physical blowing agent. The mechanical, thermal, rheological properties, and crystallization behavior were also studied. By the incorporation of PEG, the impact strength of the PLA/PEG blends improved by 98% with the specimens fractured in a ductile mode. The crystallization process of the blends was accelerated, and the crystallinity was significantly increased to 45.1%. The viscoelasticity of the PLA/PEG matrix was weakened, and the cells tended to break at the cell wall during cell expansion; thus, a highly interconnected structure with a maximum porosity of 82.3% was obtained. Moreover, the PLA/PEG blends exhibited higher cell densities and smaller cell size, compared to their neat counterparts. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3066–3073, 2013 相似文献
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对全氟辛酸、ω-氯代氧杂全氟癸酸、癸酸钠及三种a-磺基癸酸盐与烷基三甲铵盐混合水溶液起泡性质进行了研究。结果表明,ω-氯代氧杂全氟癸酸有很低的临界胶团浓度,仟低水表面张力的能力很强,并有很好的起泡性能。它与溴化辛基三甲铵混合体系的起泡性却与一般正负表面活性剂混合体系迥异,混合体系的起泡性反劣于单一体系。这破归之于ω-氯代结构的特殊影响。全氟辛酸和三种a-磺基癸酸衍生物与烷基三甲铵盐混合水溶肤泡沫性质比单一溶液均显著增强,而癸酸钠与烷基三甲铵盐混合水溶液起泡性却明显削弱。 相似文献
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Asymmetric micro porous membranes have been prepared successfully from blending of cellulose acetate (CA) and polyethersulfone
(PES) by the phase inversion method with N, N-dimethylformamide (DMF) as solvent. Two additives were selected in this study, including polyethylene glycol 600 (PEG 600)
and polyvinylpyrrolidone (PVP). The effects of concentration of additives on CA/PES blend membrane performance and cross-section
morphology were investigated in detail. CA/PES membranes were compared with CA/PES/PEG and CA/PES/PVP membranes in the performance
such as pure water flux, membrane resistance, porosity and cross-section morphology. The resulting blend membranes were also
carried out the rejection and permeate flux of Egg Albumin (EA) proteins with molecular weight of 45 Da. The membranes thus
obtained with an additive concentration of 5 wt% of both PEG and PVP exhibited superior properties than the 80/20% blend composition
of CA and PES membranes. The permeate flux of protein was increased from 44 to 134 lm2 h with increase in concentrations of both PVP and PEG in 80/20% blend composition of CA and PES membranes. Cross-sectional
images from scanning electron microscopy showed larger macropores in the bottom layer of the membranes with increasing additives
content. Observations from scanning electron microscopy provided qualitative evidence for the trends obtained for permeability
and porosity results. 相似文献
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烷基二苯醚二磺酸盐的制备与性能表征 总被引:14,自引:2,他引:12
制备了一类由刚性基团联接的特殊双亲水基型阴离子表面活性剂———十二烷基二苯醚二磺酸钠(C12-MADS)、双十二烷基二苯醚二磺酸钠(C12-DADS)及十六烷基二苯醚二磺酸钠(C16-MADS),并对其性能进行了研究。25℃时3种烷基二苯醚二磺酸钠的CMC分别为1 16×10-3、1 10×10-5和4 51×10-4mol/L,γCMC分别为44 9、43 5和46 8mN/m,C12-MADS和C16-MADS在浓度分别为2 21×10-2和3 80×10-2mol/L时的胶束聚集数(Nm)分别为24和29。合成的烷基二苯醚二磺酸钠在质量分数高达0 1的无机酸、碱和盐溶液中保持稳定,发泡性低于烷基苯磺酸钠(LAS),但乳化性能优于LAS。C12-MADS在650mg/L硬水中去污比值为14 05%,明显高于LAS(7 18%)。C12-MADS和C12-DADS在4d后的生物降解度≥90%。该类表面活性剂具有优良的应用性能。 相似文献
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Magdy M. Senna Hussein A. Youssef Hannan M. Eyssa 《Polymer-Plastics Technology and Engineering》2013,52(11):1093-1101
The effect of electron beam irradiation, EPDM blending, and Azodicarbonamide (ACA) concentration on the foaming properties of LDPE sheet was investigated. The studied properties are foaming degree, cell densities, mechanical properties and thermal decomposition properties. The data showed that the increasing of foaming agent (ACA) concentration reduces the mechanical properties and increases the gel content. Also, electron beam irradiation has a clear effect on increasing the cell density, mechanical properties gel content and thermal properties of irradiated samples when compared with unirradiated samples. EPDM blending with LDPE at a concentration of 20% reduces the doses required to obtain the foaming degree (71.4%) from 50 kGy in LDPE to 5 kGy in LDPE/EPDM (80/20%). This effect may be attributed to enhancement of radiation cross-linking for LDPE by blending with the amorphous polymer (EPDM). 相似文献