共查询到20条相似文献,搜索用时 125 毫秒
1.
EXPERIMENTALINVESTIGATIONOFKINETICANDTRANSPORTPARAMETERSINAWALL-COOLEDFIXED-BEDREACTORZhen-MinCHENGandWei-KangYUAN(UNILABRese... 相似文献
2.
国内外增强用玻璃纤维的现状与发展 总被引:1,自引:0,他引:1
国内外增强用玻璃纤维的现状与发展林树益,高建枢,朱晶莹(南京玻璃纤维研究设计院210012)STATUSANDDEVELOPMENTOFREINFORCEDGLASSFIBERATHOMEANDABROAD¥LinShuyi;GaoJianshu;Z... 相似文献
3.
1—2折流换热器流体温度沿程变化及其LMTD的计算 总被引:1,自引:0,他引:1
1-2折流换热器流体温度沿程变化及其LMTD的计算梁日忠THEVARIATIONOFFLUIDTEMPERATUREALONGSIDPASSANDTHECALUATIONOFLMTDIN1-2BAFFLEHEATEXCHANGER1前言换热器设计中,... 相似文献
4.
《高校化学工程学报》1994,(Z1)
LARGESCALEPURIFICATIONOFPHOSPHOGLYCERATEKINASE(PGK)ANDGLYCERALDEHYDE3-PHOSPHATEDEHYDROGENASE(GAPDH)FROMYELLOWPEASBYPEG/REPPAL... 相似文献
5.
《高校化学工程学报》1994,(Z1)
THEORETICALSTUDIESONREACTIONSELECTIVITYIMPROVEMENTFORREDUCTIONOFNITROBENZENEINAPACKED-BEDELECTRODEREACTORUNDERPERIODIC-CURREN... 相似文献
6.
《感光科学与光化学》1995,(1)
SEMICONDUCTINGPOLYMERDEVICES:NEWDEVELOPMENTSYUGANG(InstituteforPolymersandOrganicSolidsUniversityofCaliforniaatSantaBarbara,S... 相似文献
7.
THEPREPARATIONOFHIGH-PURITY,ULTRAFINEANDMONODISPERSEDTITANIUMDIOXIDEPOWDERFROMTITANIUMTETRACHLORIDEBYHYDROLYSISOFTITANIUMALKO... 相似文献
8.
《感光科学与光化学》1996,(2)
STRUCTURALANDPHOTOELECTRICPROPERTIESOFANOVELAMPHIPHILICZINCPHTHALOCYANINEMIXEDLBMULTILAYERS¥LIHongwu;CHENTiefeng;WANGHanhui;Z... 相似文献
9.
稀土对聚氯乙烯(PVC)的热稳定作用李昕THERMALSTABILIZATIONOFRAREEARTHSONPVC1前言聚氯乙烯(PVC)是世界五大通用塑料之一,1987年,FVC树脂产量约600kt,制成品约800kt,1990年PVC树脂产量将近... 相似文献
10.
国内外汽车玻璃钢市场的现状与展望 总被引:1,自引:0,他引:1
李湘洲 《玻璃钢/复合材料》1994,(1):37-39
国内外汽车玻璃钢市场的现状与展望李湘洲(长春建筑材料工业学校130022)CURRENTSITUATIONANDPROSPECTOFMARKETFORAUTOMOBILEFRPATHOMEANDABROAD¥LiXisligzhou(Changchu... 相似文献
11.
The effects of rubber particle size and rubber/matrix adhesion on the impact properties of a brittle polymer have been separated using polystyrene (PS)/acrylonitrile-butadiene rubber (NBR) as a model system in which interfacial chemical reaction could be controlled. It has been proven that the interfacial adhesion between the rubber phase and the PS matrix not only greatly aids in reducing the rubber particle size but also plays a further role in improving the impact properties of the matrix polymer. The impact energies of PS/NBR blends with interfacial chemical bonding are four to ten times as high as those without interfacial bonding for the same average rubber particle size. However, at temperatures below the glass transition temperature of the rubber, there is no difference in impact energies with or without interfacial chemical bonding. It has been found that the optimum rubber particle size for toughening PS is influenced by interfacial adhesion. Smaller optimum rubber particle size is observed for blends with greater amounts of interfacial chemical bonding. 相似文献
12.
采用机械共混法和乳液共沉法制备了NBR/PVC共混胶,通过差示扫描量热仪(DSC)和场发射扫描电子显微镜(FE-SEM)对共混胶的微观形貌、结构进行了表征,考察了共混方式和共混胶配比对其力学性能的影响,并比较了共混胶、CPE、P-83对硬质/软质PVC的改性效果。结果表明:①与机械共混胶相比,乳液共沉胶混合得更均匀,分散性更好,其分子级混合程度更好;②乳液共沉胶试样的力学性能在总体上优于机械共混胶;③对于硬质PVC,CPE的改性效果优于其他改性剂;④对于软质PVC,乳液共沉胶的改性效果最好,特别是对撕裂强度的提高非常明显。 相似文献
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14.
The effect of chlorinated polyethylene (CPE) content and test temperature on the notched Izod impact strength and brittle‐ductile transition behaviors for polyvinylchloride (PVC)/CPE blends and PVC/CPE/nano‐CaCO3 ternary composites is studied. The CPE content and the test temperature regions are from 0–50 phr and 243–363 K, respectively. It is found that the optimum nano‐CaCO3 content is 15 phr for PVC/CPE/nano‐CaCO3 ternary composites. For both PVC/CPE blends and PVC/CPE/nano‐CaCO3 ternary composites, the impact strength is improved remarkably when the CPE content or test temperature is higher than the critical value, that is, brittle‐ductile transition content (CBD) or brittle‐ductile transition temperature (TBD). The TBD is closely related to the CPE content, the higher the CPE content, the lower the TBD. The temperature dependence of impact strength for PVC/CPE blends and PVC/CPE/nano‐CaCO3 ternary composites can be well simulated with a logistic fitting model, and the simulation results can be illustrated with the percolation model proposed by Wu and Jiang. DMA results reveal that both PVC and CPE can affect the TBD of PVC/CPE blends and PVC/CPE/nano‐CaCO3 composites. When the CPE content is enough (20 phr), the CPE is more important than PVC for determining the TBD of PVC/CPE blends and PVC/CPE/nano‐CaCO3 composites. Scanning electron microscopy (SEM) observations reveal that the impact fractured mechanism can change from brittle to ductile with increasing test temperature for these PVC systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
15.
本文用Brabender塑化仪,双锟开炼机研究了刚性有机粒子对PVC/CPE共混体熔融塑化为及力学性能的影响,探讨了不同加工温度对PVC/CPE共混体力学性能的影响,实验表明:添加少量刚性有机粒子后,体系的塑化时间缩短,塑化行为改善,韧性有较大幅度提高,拉伸强度有所改善,加工温度为160-180℃体系性能最好。 相似文献
16.
本文研究刚性聚合物(PS、PMMA)对CaCO_2填充的PVC/CPE共混体力学性能和流变性能的影响。结果表明,刚性聚合物的填入提高了共混体的冲击强度,其中,对PVC/CPE/CaCO_3=100/15/10体系的增韧效果较好。PMMA使共混体的拉伸强度有所提高而PS使共混体拉伸强度下降。流变性的测定显示,Ca-CO_2使共混体的表观粘度和粘流活化能增加,牛顿的流动性增强,而在PVC/CPE/CaCO_3共混体中加入4.5份PS能明显降低共混体的表观粘度和粘流活化能,牛顿的流动性降低,但仍有良好的挤出物外观和较低的挤出膨胀率。 相似文献
17.
Chao Zhou Qing-Bo Si Yu-Hui Ao Zhi-Yong Tan Shu-Lin Sun Ming-Yao Zhang Hui-Xuan Zhang 《Polymer Bulletin》2007,58(5-6):979-988
Summary PB-g-MMA core-shell impact modifiers were synthesized by seed emulsion polymerization and impact-modified PMMA/PVC blends
were prepared by melt blending PMMA, PVC and PB-g-MMA at 160 °C. The PB-g-MMA particles were dispersed uniformly in the PMMA/PVC
matrix. PMMA/PVC blends were prepared in the blend ratio from 100/0 to 0/100 and the rubber content was kept 16% in all the
compositions. The effects of matrix composition on the mechanical properties and morphology of the blends were studied. It
was found that when the matrix was a PMMA-rich system, the sample broke in a brittle mode and crazing of the matrix was the
main mechanisms of deformation. When the matrix was a PVC-rich system, the sample broke in a ductile mode and the main deformation
mechanisms were cavitation of the particle and shear yielding of the matrix. There existed a transition from crazing to shear
yielding in the rubber-modified PMMA/PVC blend as the matrix composition varied. 相似文献
18.
有机刚性填料对PVC韧性的影响 总被引:4,自引:0,他引:4
用拉伸实验和冲击实验研究了聚甲基丙烯酸甲酯(PMMA)、聚苯乙烯(PS)等有机刚性填料(ROF)对聚氯乙烯(PVC)韧性的影响。实验表明PMMA、PS对PVC具有一定的增韧作用,并且其增韧机理与弹性体增韧不同。 相似文献
19.