共查询到20条相似文献,搜索用时 187 毫秒
1.
2.
3.
4.
5.
6.
本文通过动态力学谱(DMS)研究了树脂硫化丁基橡胶时树脂类型对其动态力学性能的影响。发现:以2402树腊(对—叔丁基苯酚甲醛树脂)和以WS树脂(对—特辛基苯酚甲醛树脂)硫化的丁基橡胶,其动态力学性能差异较大。在同样条件下,以WS树脂硫化的丁基橡胶,其Tg(玻璃化温度)随硫化时间的延长而升高,且在较高温区的宽温域内具有较好的阻尼性能。 相似文献
7.
8.
IIR/CIIR共混胶硫化特性的研究 总被引:5,自引:0,他引:5
研究了影响丁基橡胶/氯化丁基橡胶(IIR/CIIR)共混胶硫化特性的因素.包括并用比、硫化体系、补强剂和硅炕偶联剂。研究结果表明:随着IIR/CIIR共混胶中CIIR含量的增加,硫化速度加快,是大转矩值减小:用硫磺硫化的共混胶硫化速度比用树脂硫化的快,且共混胶起始转矩值也较高。在选用的几种补强剂中,添加N220补强的共混胶硫化速度较快,T90时间较短,添加活性沉淀白炭黑(WCB)补强的共混胶最大转矩值较高。加入硅烷偶联剂会使共混胶的T90时间延长,最大转矩值变高。 相似文献
9.
研究了不同并用质量比的氯化丁基橡胶/溴化丁基橡胶(CIIR/BIIR)共混胶的硫化特性、力学性能、老化性能和动态力学性能。结果表明,不同并用质量比的CIIR/BIIR共混胶相容性良好,仅有一个损耗因子(tan δ)峰,随着BIIR用量提高,共混胶的交联程度略降低,正硫化时间延长,硫化速率减慢,力学性能没有明显变化,玻璃化转变温度明显向高温偏移;当CIIR/BIIR并用质量比为90/10时,共混胶的动态力学性能达到最优,60℃的tan δ值比纯BIIR硫化胶降低19%。 相似文献
10.
11.
树脂对硅橡胶性能的影响 总被引:1,自引:1,他引:0
研究了PS树脂、2112树脂、C5/C9石油树脂等3种树脂时硅橡胶混炼胶力学性能和阻尼性能的影响.结果表明,加入PS树脂可提高硅橡胶的力学性能,加入C5/C9石油树脂或2112树脂对硅橡胶力学性能无明显影响;加入C5/G9石油树脂和2112树脂对硅橡胶阻尼性能无明显影响,但加入PS树脂对硅橡胶高温阻尼性能有一定改善作用;加入C5/C9石油树脂和2112树脂对硅橡胶的高低温模量变化影响不大,但加入PS树脂使硅橡胶的高低温模量变化超过2个数量级,影响其模量稳定性,不利于在高低温环境下减振材料的实际应用. 相似文献
12.
The devulcanization of resin‐cured unfilled butyl rubber with a grooved‐barrel ultrasonic reactor under various processing conditions was carried out. The experiments indicated that, because of the lower unsaturation and good thermal stability of butyl rubber, its devulcanization could be successfully accomplished only under severe ultrasonic‐treatment conditions. Gel permeation chromatography measurements were carried out for the virgin gum and sol part of devulcanized samples to study the changes in the rubber network during the devulcanization process. The obtained data showed a significant molecular weight reduction and a broadening of the molecular weight distribution upon devulcanization, which indicated that the devulcanization and degradation of butyl rubber occurred simultaneously. The rheological properties showed that devulcanized butyl rubber was more elastic than the virgin gum. The vulcanizates of the devulcanized butyl rubber showed mechanical properties comparable to those of the virgin vulcanizate. The thermal behaviors of the virgin and devulcanized butyl rubber were different and were correlated to the double‐bond content. The structural characteristics of the devulcanized butyl rubber were simulated with the Dobson–Gordon theory of rubber network statistics. A fairly good agreement between the experimental data and theoretical prediction was achieved. The simulation of devulcanized butyl rubber indicated that the rate of crosslink rupture was much higher than that of the main chain. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1316–1325, 2004 相似文献
13.
采用超临界CO2流体作传输介质,二苯基二硫(DD)作脱硫剂,研究了废旧丁基橡胶的脱硫再生。结果表明,所得丁基橡胶再生胶(RIIR)不能被硫黄硫化,但能被树脂硫化。在丁基橡胶(IIR)的硫黄硫化过程中,DD不能用作硫化剂和硫化促进剂,其对硫化过程有明显的抑制作用。采用丙酮抽出残留DD后,RIIR可被硫黄硫化。针对IIR/RIIR并用体系,分别以硫黄和树脂作硫化体系且用量相同时,树脂硫化体系的交联密度明显高于硫黄硫化体系。 相似文献
14.
Effects of degree of crosslinking in butyl rubber on the flow behavior and morphology of crosslinkable polyethylene (XLPE) and butyl rubber blends have been studied as a function of shear rate and processing temperature. Viscosity, flow activation energy, and rheological parameters have been studied with reference to the effect of blend compositions. Low-crosslinked butyl rubber showed higher normal stress difference than the highly crosslinked butyl rubber in the blend. As evidenced from extrudate swell, melt compliance, and Reynolds number, phase reversion in low-crosslinked butyl rubber occurred within a narrow composition range whereas in highly crosslinked butyl rubber blends, the change occurred over a wide composition range. Change of phase has also been confirmed by SEM examination. Highly crosslinekd butyl rubber showed higher elastic response than low-crosslinked rubber. 相似文献
15.
We have conducted a study of composite polymer particles with a gradated resin composition by suspension polymerization, in which the resin composition gradually changes from the surface to the center of the particles. The binder resin of the polymer particles consists primarily of styrene, butyl acrylate, and methacrylic acid (MAA). Fourier transform infrared/photoacoustic spectroscopy analysis of the polymer particles by suspension polymerization has proved that MAA, having a higher polarity, concentrates near the surface of the particles, and this results in a formation similar to a core–shell structure. These composite polymer particles are excellent in blocking resistivity because the resin, containing a higher concentration of MAA, has a high glass‐transition temperature. Composite polymer particles with a gradated MAA concentration could be used for toner applications in low‐power hot‐roll fusing electrophotography systems because the melting property of the core resin is controlled and allows fusing at lower temperatures. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 682–690, 2005 相似文献
16.
采用单因素变量法研究了不同的生胶(107胶)分子量,硅烷交联剂、催化剂以及硅烷偶联剂对缩合型室温硫化(RTV)硅橡胶耐热空气老化的影响,并初步探讨了自制有机硅高沸树脂对RTV硅橡胶在空气中耐热性的影响。通过热重分析仪(TGA)表征了RTV硅橡胶的热失重。结果表明,催化剂对RTV硅橡胶的耐热性有很大影响。有机硅高沸树脂可适当提高RTV硅橡胶的耐热性能,且在一定范围内,RTV硅橡胶的最大热失重温度和最终残炭率均随高沸树脂添加量的增加而增加。耐热性较好的RTV硅橡胶组分为:较高分子量的107胶、正硅酸乙酯、氨丙基三乙氧基硅烷、钛酸丁酯,以及适量的有机硅高沸树脂。 相似文献
17.
聚丙烯酸酯液体橡胶增韧环氧树脂体系研究 总被引:2,自引:0,他引:2
采用溶液聚合法合成了以丙烯酸丁酯、丙烯酸乙酯、丙烯酸缩水甘油酯为主链的液体橡胶,将其用于增韧改性环氧树脂/间苯二甲胺(EP 828/mXDA)体系,研究了聚丙烯酸酯液体橡胶用量对共混体系的微观形态、力学性能和玻璃化温度的影响。电镜观察显示液体橡胶改性EP828/mXDA的共混物呈海岛结构,连续相为环氧树脂,分散相为液体橡胶。随着丙烯酸酯液体橡胶用量增加,海岛相区的粒径和数量均呈增长趋势。当丙烯酸酯液体橡胶质量分数为15%时,共混物中海岛相区的尺寸为1μm左右,共混体系的冲击强度增加151.8%,玻璃化温度下降11.3℃。以丙烯酸液体橡胶改性EP828/mXDA环氧树脂体系,可以较大程度提高其韧性,同时其耐热性基本保持不变。 相似文献
18.
19.
The electron-microscopic visualization of acrylic rubber dispersed in a heterogeneous structural resin composition consisting of a rubber-modified two-phase plastic comprising essentially a butyl acrylate rubber phase and an acrylonitrile–styrene copolymer phase, respectively, has been accomplished. This procedure consists of the following: The molded resin specimen is treated with hydrazine hydrate solution to produce the acrylic acid hydrazides. Allow the treated specimen to soak in osmium tetroxide solution. The acrylic rubber may be indirectly fixed and stained. Some micrographs of ultrathin sections of two or three resin compositions, cut by an ultramicrotome, are presented. 相似文献