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1.
NBR/PP热塑性弹性体研究进展 总被引:12,自引:0,他引:12
阐述了NBR/PP共混热塑性弹性体动态硫化胶的国内外研究进展、微观相态结构、性能、应用及展望。 相似文献
2.
E. M. Abdel-Bary H. H. Hassan A. M. El-Lawindy M. K. Abu-Assy F. K. El-Tantawy 《Polymer International》1993,30(3):371-374
Butyl rubber mixtures loaded with 70 phr general purpose furnace black (GPF) and tetramethyl thiuram disulphide (TMTD)/S as vulcanizing system were prepared. The kinetics of their electrical conductivity development during the vulcanization process were followed by using an especially devised system. It was found that the increase in the electrical conductivity during vulcanization obeys an exponential growth function with time constant τ, which markedly decreases with increasing vulcanization temperature as well as with the efficiency of the vulcanizing system. After completion of the vulcanization process, about 80 min, the samples obtained possess reasonable stability and reproducibility of electrical conductivity. 相似文献
3.
研究3种牌号丁苯橡胶(SKMS-10,SL-4525-0,SBR1502)的硫化特性、物理性能和耐低温性能。结果表明:SKMS-10具有优异的耐低温性能,生胶的玻璃化转变温度(Tg)为-73.3℃,硫化胶的Tg为-59.8℃,适于在极寒条件下使用;SL-4525-0胶料的Fmax-FL较大,硫化胶的拉伸强度为19.3 MPa,撕裂强度为53 kN·m-1,Tg为-48.6℃,具有优异的综合性能;SBR1502硫化胶的拉伸强度高达24.9 MPa,撕裂强度为49 kN·m-1,但Tg为-38.4℃,耐低温性能较差,适用于载荷较大且耐低温性能要求不高的橡胶减振制品。 相似文献
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根据国外动态硫化技术的发地趋势,结合国内科研情况.对TPV推广应用的可能性进行了分析,并对今后的发展提出了建议。国内TPV的主要应用市场是轿车及电线电缆行业。顶计2000年,轿车行业对TPE的需求量达3250t/a。国内EPDM/PPTPV工厂成本不超过1.7万元/t.售价将远低于Santoprene。 相似文献
6.
乙烯-辛烯共聚物/再生丁基橡胶热塑性弹性体的制备及其性能 总被引:2,自引:0,他引:2
采用动态硫化法制备了乙烯-辛烯共聚物(POE)/再生丁基橡胶(RIIR)热塑性弹性体(TPE),考察了共混比、硫黄、软化剂白油和炭黑N330对TPE力学性能的影响,研究了TPE的动态力学性能和流变性能。结果表明,当POE/RIIR(质量比)为2/1、硫黄为0.5份、软化剂白油为20份、炭黑为30份时,TPE的综合力学性能较佳;POE和RIIR具有较好的相容性;当体系中加入白油时,TPE的动态复数黏度(η*)降低,炭黑的加入使TPE的η*迅速增大。 相似文献
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Composites based on natural rubber (NR) and containing organophilic and pristine layered silicates of natural and synthetic origin were produced by melt compounding and sulfur curing. The curing, thermomechanical, and mechanical properties of the mixes, which contained 10 phr (parts per hundred parts of rubber) silicates, were determined. The dispersion of the silicates was studied by X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Organophilic clays accelerated the sulfur curing of NR, which was believed to occur because of a complexation reaction in which the amine groups of the clay intercalants participated. The property improvements caused by the fillers were ranked as follows: organophilic clays > pristine synthetic layered silicate (sodium fluorohectorite) > pristine natural clay (purified sodium bentonite) > precipitated nonlayered silica (used as a reference). This was attributed to partial intercalation of the organophilic clay by NR on the basis of XRD and TEM results and to the high aspect ratio of the fluorohectorite. Apart from intercalation, severe confinement (i.e., the collapse of the interlayer distance) of the organoclays was observed. This peculiar feature was traced to the formation of a zinc coordination complex, which extracted the amine intercalant of the organoclays, thus causing the collapse of the layers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 813–819, 2004 相似文献
9.
Black rice husk ash (BRHA) and white rice husk ash (WRHA) were incorporated into natural rubber (NR) using a laboratory‐size two‐roll mill. A conventional vulcanization system (CV) was chosen and cure studies were carried out on a TI‐100 Curometer. The torque curves were obtained at 150, 160, 170, and 180°C. The overall rate and the apparent activation energy for the vulcanization process were calculated for each compound assuming that vulcanization follows first‐order kinetics. For comparison purposes, two commercial fillers, precipitated silica (Zeosil‐175) and carbon black (N762), were also used. It was observed that addition of WRHA to NR compounds increased the cross‐linking rate and lowered the apparent activation energy more markedly than the other fillers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1194–1203, 2003 相似文献
10.
叙述硫化外胎胎冠花纹沟露线、胎冠中心线露线、胎肩露线、胎圈露线以及胎里露线等问题的特征和弊端,提出结构设计、生产工艺和设备条件各方面的预防和改进措施:同一规格、不同花纹的轮胎要用不同的胎面挤出口型,胎肩曲线、内衬层厚度等设计要合理;压延、挤出、成型和定型、硫化各工序要严格执行工艺规程;要经常检查硫化设备运行状况,对磨损和老化部件及时更换。 相似文献