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991.
积层多层板用UV油墨的合成研究   总被引:1,自引:0,他引:1  
采用丙烯酸改性环氧树脂E-44的方法,合成了环氧丙烯酸酯预聚物,并将其用在UV光固化油墨的配方中。在树脂合成过程中,研究了反应温度,催化剂,阻聚剂等因素对合 产品的影响。通过L9(3^4)正交试验,得到了优化的工艺参数:反应温度为90℃,催化剂为N,N-二甲苯胺,用量1%;阻聚剂对苯二酚,用量0.5%,投料环氧树脂和丙烯酸的摩尔比为1:1.08。  相似文献   
992.
压挤成形--固化法制备0-3型压电复合材料的性能研究   总被引:2,自引:0,他引:2  
详细地叙述了室温压挤成形———固化工艺制备 0 -3型压电复合材料工艺 ,使用XRD、SEM和HP42 94测试并分析了样品的结构和性能 ,并与压电陶瓷性能参数进行了对比 ;同时用这种工艺制备可以获得介电损耗小、机电耦合系数为 2 5 .11%、压电应变常数为 3 2PC N和机电品质因数可达到 3 0 2的 0— 3型压电复合材料。  相似文献   
993.
20世纪90年代以来撞击流领域研究重点转向以液体为连续相。液体连续相撞击流(US)具有有效促进微观混合和存在压力波动的特性,从而有利于超细粉体的制备。实验结果表明,浸没循环撞击流反应器(SCISR)是反应一沉淀法制取超细粉体的一种优越的反应技术装备。  相似文献   
994.
Three different polyethylene/polypropylene (PE/PP) blends were microcellular foamed and their crystallinities and melt strengths were investigated. The relationship between crystallinity, melt strength, and cellular structure was studied. Experimental results showed that the three blends had similar variation patterns in respect of crystallinity, melt strength, and cellular structure, and these variation patterns were correlative for each blend. For all blends, the melt strength and PP melting point initially heightened and then lowered, the PP crystallinity first decreased, and then increased as the PE content increased. At PE content of 30%, the melt strength and PP melting point were highest and the PP crystallinity was least. The blend with lower PP crystallinity and higher melt strength had better cellular structure and broader microcellular foaming temperature range. So, three blends had best cellular structure at PE content of 30%. Furthermore, when compared with PE/homopolymer (hPP) blend, the PE/copolymer PP (cPP) blend had higher melt strength, better cellular structure, and wider microcellular foaming temperature range, so it was more suited to be microcellular foamed. Whereas LDPE/cPP blend had the broadest microcellular foaming temperature range because of its highest melt strength within three blends. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 4149–4159, 2007  相似文献   
995.
分析了国内外汽车工业对塑料的市场需求现状与趋势,提出了"十·五"期间塑料在我国汽车领域的应用方向与发展思路.  相似文献   
996.
Summary: Poly(ethylene 2,6‐naphthalate) (PEN) can crystallize either from the glassy state or from the melt state. When crystallized from the glassy state, the sample was quenched from the melt in liquid nitrogen and then annealed at certain crystallization temperatures. When crystallized from the melt state, the sample was cooled to a preset temperature from the melt and then annealed for a certain time. The crystal modifications, morphologies and melting behaviors of PEN were investigated by means of wide‐angle X‐ray diffraction (WAXD), polarized optical microscopy (POM), small‐angle light scattering (SALS) and differential scanning calorimetry (DSC). The results show that an α crystal modification of PEN was obtained when PEN crystallized from the glassy state, whilst a β crystal modification was obtained when PEN crystallized from the melt state at a higher temperature. An hedritic morphology of PEN crystal was obtained with only one melting peak observed in DSC curves when PEN was crystallized at a higher temperature from either the glassy state or the melt state. The α crystal modification could also be obtained when PEN was crystallized at a lower temperature from the melt. Spherulitic or banded spherulitic morphologies of PEN crystals, exhibiting multiple melting peaks in DSC curves, were observed when PEN was crystallized at a lower temperature. The multiple melting behaviors of PEN crystals may be associated with spherulitic structures composed of lamellae of varying thickness.

WAXD patterns of PEN isothermally crystallized from different states.  相似文献   

997.
洗车废水回用技术的研究应用进展   总被引:5,自引:1,他引:5  
洗车废水含有油污,泥沙,表面活性剂及其他可溶性有机物。洗车废水处理回用技术因洗车规模大小不同存在很大差别。该文介绍了目前国内外大型洗车场废水处理回用的主要工艺,概括和比较了洗车点洗车废水回用装置的主要技术,分析了目前小型回用装置存在的问题,并对发展方向作了展望。  相似文献   
998.
Butan‐1‐ol modified toluene diisocyanate tri mer (TDI‐trimer) was synthesized and characterized with Fourier transform infrared spectroscopy, gel permeation chromatography, and thermal gravimetry analysis techniques. The modified TDI‐trimer showed good dissolvable ability with hydroxy resin and can be used to produce paints with acrylic polyol resin. The thermal stability of the modified TDI‐trimer was improved by simply increasing both the amount of catalyst and the ratio of ? NCO/? OH, less depended on the kind of catalyst. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4958–4962, 2006  相似文献   
999.
天然肉桂油臭氧化制取苯甲醛   总被引:10,自引:4,他引:10  
利用天然肉桂油中富含的肉桂醛,经过臭氧化反应和还原反应制得了苯甲醛。由该法制得的苯甲醛在国际上可作为天然苯甲醛使用。  相似文献   
1000.
Poly(methyl methyacrylate)‐block‐polydimethylsiloxane (PMMA‐b‐PDMS) copolymers with various compositions were synthesized with PDMS‐containing macroazoinitiator (MAI), which was first prepared by a facile one‐step method in our lab. Results from the characterizations of X‐ray photoelectron spectroscopy (XPS), contact angle measurements, and atomic force microscopy (AFM) showed that the copolymer films took on a gradient of composition and more PDMS segments enriched at the film surfaces, which then resulted in the low surface free energy and little microphase separation at the film surfaces. By contrast, transmission electron microscopy (TEM) analysis demonstrated that distinct microphase separation occurred in bulk. Slight crosslinking of the block copolymers led to much steady morphology and more distinct microphase separation, in particularly for copolymers with low content of PDMS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   
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