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21.
动态硫化EPDM/PP热塑性弹性体的研究进展   总被引:2,自引:0,他引:2  
阐述了EPDM/PP共混型热塑性弹性体的发展历史、微观结构、性能、硫化体系、制备工艺、加工设备及研究展望。  相似文献   
22.
机械混炼制备碳纳米管/天然橡胶复合材料特性分析   总被引:7,自引:2,他引:7  
通过机械混炼方法将碳纳米管与天然橡胶复合,与炭黑补强样品相比,碳纳米管在橡胶中的混入速度快,功率消耗低,温升幅度小,混炼胶的硫化焦烧时间略有增加,硫化返原现象减轻,硫化剂用量应适当增加。加入碳纳米管后,橡胶DSC曲线中的结晶熔融峰面积减少,交联反应放热峰变宽。碳纳米管复合材料的回弹、压缩疲劳性能明显优于炭黑补强样品,耐老化性能较好,拉伸、撕裂性能水平有待提高。  相似文献   
23.
稀土BR/SBR共混胶的性能   总被引:1,自引:0,他引:1  
研究了4种共混比的LnBR/SBR共混生胶、混炼胶及硫化胶的性能,并与NiBR/SBR共混胶进行了对比。结果表明,共混生胶的ML均低于LnBR及SBR;当LnBR/SBR共混混炼胶的ML、剪切应力、出口膨胀及硫化速度均低于NiBR/SBR共混胶,挤出物外观优于后者;共混硫化胶的拉伸强度、热空气老化、拉伸疲劳、湿滑、耐磨等性能均明显优于后者,生热和透气率高于后者。  相似文献   
24.
Hygrothermally decomposed polyurethane (HD‐PUR) was mixed up to 20 phr in epoxidized natural rubber (with 50 mol % epoxidation; ENR50) recipes, and the curing and mechanical behaviors were studied. Mechanical testing of the ENR50/HD‐PUR vulcanizates determined the tensile, tear, compression‐set, hardness, abrasion, hysteresis, and resilience properties. No significant changes were observed in the tensile properties with the incorporation of HD‐PUR. The ENR50 compounds showed an increase in compression set with increasing HD‐PUR content. Rubbers cured by a semi‐efficient vulcanization system gave the best overall performance. A further improvement in curing and mechanical properties was achieved by the carbon black grade N330 being replaced with a more active grade (N375). © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2265–2276, 2002  相似文献   
25.
综述了离子交联无规羧基橡胶(羧基橡胶)的制备方法、硫化方法、硫化胶性能及其用途,指出了羧基橡胶今后的发展方向。  相似文献   
26.
缩合型室温硫化硅橡胶耐热性的研究进展   总被引:5,自引:1,他引:5  
从硅橡胶的分子结构分析了其耐热性优于普通橡胶的原因及热老化机理,并比较了几种硫化体系的缩合型室温硫化硅橡胶的耐热性,着重介绍了国内外提高室温硫化硅橡胶耐热性的方法和研究进展。  相似文献   
27.
The potential application of lignin biopolymer as a component of styrene–butadiene rubber was examined with regard to its ability to reinforce the vulcanizates. It was shown that the sulfur‐free lignin preparation improved physicomechanical properties of rubber. The determination of the coefficient of lignin activity confirmed that lignin acts as an active filler. FTIR characteristics of lignin isolated from the vulcanizate containing 20 phr lignin indicated its interaction with the sulfur system, resulting in formation of noncyclic sulfide structures. In the case of higher lignin amount in the vulcanizate, some interfacial interaction between lignin and SBR may occur. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 924–929, 2005  相似文献   
28.
The effect of a number of thiophosphoryl compounds [viz., bis(isobutyl) thiophosphoryl di‐, tri‐, and tetrasulfides and bis(dicyclohexyl) thiophopsphoryl di‐, tri‐, and tetrasulfides] on natural rubber (NR)‐carboxylated nitrile rubber (XNBR) blend was studied. All these thiophosphoryl compounds are capable of forming interrubber links leading to covulcanized blends which exhibit a fair degree of synergism with respect to physical properties, the maximum being obtained at the 25% NR and 75% XNBR blend composition. This is an obvious claim that the blend under investigation is technologically compatible, having some degree of interrubber interaction which is enhanced in case of two‐stage vulcanization. The existence of interrubber interaction is judged by the swelling experiment. The blend morphology assessed by SEM micrographs corroborates the foregoing observations and accounts for the significant improvement in physical properties of the blend vulcanizates, particularly in two‐stage vulcanization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3286‐3299, 2002  相似文献   
29.
P Martin  C Maquet  C Bailly  M van Gurp 《Polymer》2004,45(15):5111-5125
The conjugated effects of both reactive compatibilization and dynamic vulcanization on the phase inversion behavior of poly(butylene terephthalate) (PBT)/epoxide-containing rubber blends have been studied in detail. Pure ethylene-methyl acrylate random copolymer (E-MA) and ethylene-methyl acrylate-glycidyl methacrylate random terpolymer (E-MA-GMA) were used as non reactive or reactive rubber phase, respectively. Location of the phase inversion region was studied using several techniques, including transmission electron microscopy (TEM) and dynamical mechanical thermal analysis (DMTA). To evaluate the relative influence of the blend compatibilization and the dynamic vulcanization on the phase inversion behavior, the relative kinetics of the two reactions were modified using different PBT and E-MA-GMA grades. The obtained results show unambiguously that the position and the width of the phase inversion region is essentially governed by the kinetic of the dynamic vulcanization process. The effect of the blend compatibilization remains quite limited even in the case of fast interfacial reaction. The crosslinking of the rubber phase induces an important shift of the phase inversion composition to higher rubber content. For blends containing low molecular weight PBT, up to 60 wt% of rubber can be homogeneously dispersed in the PBT matrix at long mixing time. In this case, development of high performance PBT based thermoplastic vulcanisates can be envisioned.  相似文献   
30.
HPVC/BR共混体系的性能研究   总被引:2,自引:0,他引:2  
采用动态硫化方法制备高聚合度聚氯乙烯/顺丁橡胶(HPVC/BR)共混型热塑性弹性体,考察了单一组分增容剂丁腈橡胶(NBR)、氯化聚乙烯(PE—C)和(氢化苯乙烯/丁二烯/苯乙烯)嵌段共聚物(SEBS),复合增容剂SEBS/NBR和PE—C/NBR及交联程度对HPVC/BR共温体系相容性的影响。结果表明,使用复合增容剂可明显改善HPVC/BR共混物的性能;动态硫化在改善共混物力学性能方面起主要作用。  相似文献   
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