甲基乙烯基硅橡胶/溶聚丁苯橡胶并用胶在轮胎胎面胶中的应用研究

采用甲基乙烯基硅橡胶(MVQ)与溶聚丁苯橡胶(SSBR)并用制备胎面胶,并与传统SSBR胎面胶的性能进行对比。结果表明,与SSBR胶料相比,加入相容剂T的SSBR/MVQ并用胶硫化特性和物理性能并未显著下降,耐磨性能提高,生热和滚动阻力降低,符合高性能轮胎胎面胶需求。     

白炭黑分散剂在甲基乙烯基硅橡胶/丁苯橡胶 并用胶中的应用

研究白炭黑分散剂HST和H60EF对甲基乙烯基硅橡胶(MVQ)/丁苯橡胶(SBR)并用胶性能的影响。结果表明:在MVQ/SBR并用胶中加入白炭黑分散剂HST和H60EF,可加快胶料的硫化速度,改善分散性和加工性能,提高混炼效率;白炭黑分散剂HST对MVQ/SBR并用胶的动态力学性能无明显影响,可提高撕裂强度和耐老化性能,可用作MVQ/SBR并用胶的功能性助剂。     

甲基乙烯基硅橡胶/溶聚丁苯橡胶并用胶性能的研究

研究甲基乙烯基硅橡胶(MVQ)/溶聚丁苯橡胶(SSBR)并用胶的性能,探讨并用胶表面能与耐磨和抗湿滑性能的关系。结果表明:随着MVQ用量的增大,MVQ/SSBR并用胶的物理性能和抗湿滑性能下降,摩擦因数和表面能减小,耐磨性能先提高后降低;当MVQ用量为20份时,MVQ/SSBR并用胶的综合性能最佳;MVQ/SSBR并用胶的表面能与摩擦因数和抗湿滑性能成正比;当MVQ用量小于20份时,MVQ/SSBR并用胶的表面能与耐磨性能成正比。     

硅橡胶／丁苯橡胶并用胶的硫化特性及性能研究

研究了硅橡胶与丁苯橡胶的质量比对硅橡胶／丁苯橡胶并用胶的硫化性能、力学性能及耐热老化性能的影响;探索了共混工艺对硅橡胶／丁苯橡胶并用胶力学性能的影响。结果表明,热捏合共混法能够改善硅橡胶与丁苯橡胶的相容性,提高硅橡胶／丁苯橡胶并用胶的力学性能,热捏合工艺为150℃×1h。硅橡胶与丁苯橡胶的最佳质量比为90：10。此时,与硅橡胶相比,并用胶的拉伸强度为10．58MPa,提高了28．0％;撕裂强度为51．6kN／m,提高了261％。     

团状模塑料/丁苯橡胶/甲基乙烯基硅橡胶绝缘复合材料的性能研究

制备玻璃纤维团状模塑料(DMC)/丁苯橡胶(SBR)/甲基乙烯基硅橡胶(MVQ)绝缘复合材料,并对其性能进行研究。结果表明:与采用顺丁橡胶、丁腈橡胶、丙烯酸酯橡胶和三元乙丙橡胶作相容剂相比,采用SBR作相容剂可以改善DMC和MVQ间的相容性,提高DMC/SBR/MVQ绝缘复合材料的性能,DMC/SBR/MVQ的最佳配比为60/25/75;DMC/SBR/MVQ绝缘复合材料最佳混炼工艺为分步法加入白炭黑、分批法加入DMC,分别将MVQ和SBR进行混炼,再将两种混炼胶共混均匀;最佳硫化条件为180℃/1.2 MPa×15 min。在此条件下制备的DMC/SBR/MVQ绝缘复合材料的电绝缘性能良好,阻燃性能达到电缆绝缘材料的要求。     

顺丁橡胶对硅橡胶/丙烯酸酯橡胶并用胶的增容作用

采用偏光显微镜、差示扫描量热仪以及力学性能、热老化性能测试手段,研究了顺丁橡胶(BR)增容的甲基乙烯基硅橡胶(MVQ)/丙烯酸酯橡胶(ACM)共混体系的并用比(质量比)、硫化工艺参数以及BR的加入对并用胶力学性能、耐热老化性能和相容性的影响。结果表明,BR的加入改善了MVQ/ACM并用胶的力学性能和耐热老化性能,当白炭黑用量为30份、BR/MVQ/ACM的并用比为25/45/55时,并用胶的力学性能和耐热老化性能最好;最佳硫化工艺参数为70℃×10 MPa×30 min;加入BR可以改善MVQ/ACM并用胶的相容性,且使其玻璃化转变温度降低,耐低温性能提高。     

氟橡胶/甲基乙烯基硅橡胶共混胶的性能

研究了氟橡胶(FKM)与甲基乙烯基硅橡胶(MVQ)的共混比、1,4-双叔丁基过氧异丙基苯(BIBP)硫化剂和三烯丙基异三聚氰酸酯(TAIC)助硫化剂用量以及硫化温度对FKM/MVQ共混胶硫化性能和力学性能的影响。结果表明,当FKM/MVQ共混比为50/50、硫化剂BIBP用量为1.0份、助硫化剂TAIC用量为2.5份、硫化温度为160℃时,FKM/MVQ共混胶的硫化性能和力学性能最优,硫化时其最大转矩为19.34 dN·m,拉伸强度为5.29 MPa,扯断伸长率为230.68%。     

制备工艺对甲基乙烯基硅橡胶/丙烯酸酯橡胶并用胶性能的影响

采用两种不同工艺制备甲基乙烯基硅橡胶(MVQ)/丙烯酸酯橡胶(ACM)并用胶,研究制备工艺对MVQ/ACM并用胶结构和物理性能的影响。结果表明:与分别制备MVQ/白炭黑和ACM/白炭黑混炼胶工艺相比,MVQ/白炭黑混炼胶直接与ACM共混制备的并用胶分散较为均匀,并对一段硫化诱导期具有延迟作用。该工艺制备的混炼胶在一段硫化条件为160℃×12 min、二段硫化条件为180℃×120 min时制得的并用胶的综合性能较好。     

氟橡胶/硅橡胶并用胶性能的研究

考察了不同的共混工艺对氟橡胶/硅橡胶并用胶的硫化特性、力学性能、耐热油性能、耐热老化性能以及动态力学性能的影响.实验结果表明:双硫化体系#试样硫化速度快,硫化平坦性好,硫化胶的拉伸强度达到10MPa;硅橡胶动态预硫化后再并用,其力学性能较差;三种并用胶的DMA曲线在-40℃和0℃附近分别显示硅橡胶和氟橡胶的阻尼峰,三者的tanδ相差不大,不同制备方法对氟橡胶和硅橡胶的相容性有一定影响.     

再生硅橡胶/甲基乙烯基硅橡胶共混物的性能

采用机械剪切破碎法制备再生硅橡胶,并将其掺入到甲基乙烯基硅橡胶中制备再生硅橡胶/硅橡胶共混物,研究了再生硅橡胶含量、硫化促进剂2,5-双(叔丁基过氧化)-2,5-二甲基己烷和沉淀法白炭黑用量对共混物硫化特性和力学性能的影响,通过傅里叶变换红外光谱、动态力学分析仪和扫描电子显微镜对共混物和硅橡胶进行了分析。结果表明,随着共混物中再生硅橡胶含量的增加,共混物的硫化速率变慢,力学性能降低,当再生硅橡胶质量分数为46.9%时,共混物的综合力学性能较好。当2,5-双(叔丁基过氧化)-2,5-二甲基己烷用量为0.5份(质量)且沉淀法白炭黑用量为15份时,共混物具有良好的力学性能。机械剪切破碎法没有引起再生硅橡胶化学性质的变化;共混物的玻璃化转变温度与硅橡胶接近,但其损耗因子峰值下降;共混物中填料的分散均匀性介于再生硅橡胶与硅橡胶之间。     

Preparation and properties of magnetorheological elastomers based on silicon rubber/polystyrene blend matrix

Magnetorheological (MR) elastomers, which are mainly composed of magnetic particles and elastic polymer, are a new kind of smart materials whose modulus can be controlled by changing the strength of magnetic fields. In this article, MR elastomers based on immiscible silicon rubber/polystyrene (SR/PS) blend matrix were fabricated successfully via cosolvent method and the MR effect, electric and mechanical properties, and the microstructures of the corresponding materials were studied. SEM studies showed that the dispersion of iron particles in blend matrix were different from that in single polymer, which could be further proved by the different electric conductivity. The MR effect of MR elastomers based on blend matrix varied with the different ratios of SR and PS, which was discussed in detail from the special dispersion of iron particles and of zero‐modulus of MR elastomers. In addition, the MR elastomers based on SR/PS blend matrix had enhanced mechanical properties, which made them more hopeful to be applied in practice. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3143–3149, 2007     

可分散性纳米SiO2对甲基乙烯基硅橡胶结构与性能的影响

考察了原位改性法制备的可分散性DNS-2型纳米SiO2对甲基乙烯基硅橡胶(MVQ)结构与性能的影响,并与气相法白炭黑填充MVQ进行了比较。结果表明,DNS-2-1型、DNS-2-2型和DNS-2-3型纳米SiO2为类球形颗粒,其表面改性的有机物质量分数分别为6.0%,3.9%,3.1%;DNS-2型纳米SiO2填充MVQ的加工性能及力学性能均优于气相法白炭黑填充MVQ;填充DNS-2型纳米SiO2后,MVQ的结晶温度降低,熔融吸热减小,在低温下不易硬化;DNS-2型纳米SiO2与MVQ的相容性及其在硅橡胶中的分散性优于气相法白炭黑。     

氟橡胶/甲基乙烯基硅橡胶共混弹性体的性能

通过机械共混法制备了氟橡胶(FKM)/甲基乙烯基硅橡胶(MVQ)弹性体,研究了二者的质量比对共混弹性体力学性能、耐油性能和动态力学性能的影响.结果表明,当FKM/MVQ(质量比,下同)为80/20时,共混弹性体具有较好的综合力学性能.随着FKM所占比例的增加,共混弹性体的耐油性能提高.当振动频率为1 Hz时,共混弹性体中MVQ相的玻璃化转变温度(Tg)比MVQ的Tg提高了约5.0 ℃,而FKM相的Tg改变不大;当FKM/MVQ为60/40时,随着振动频率由1 Hz增大到50 Hz,FKM相的Tg升高了12.9 ℃,而MVQ相的Tg变化不大.     

Preparation and characterization of chitosan/poly(vinyl alcohol) blend fibers

Chitosan and poly(vinyl alcohol) blend fibers were prepared by spinning their solution through a viscose‐type spinneret at 25°C into a coagulating bath containing aqueous NaOH and ethanol. The influence of coagulation solution composition on the spinning performance was discussed, and the intermolecular interactions of blend fibers were studied by infrared analysis (IR), X‐ray diffraction (XRD), and scanning electron micrograph (SEM) and by measurements of mechanical properties and water‐retention properties. The results demonstrated that the water‐retention properties and mechanical properties of the blend fibers increase due to the presence of PVA in the chitosan substract, and the mechanical strength of the blends is also related to PVA content and the degree of deacetylation of chitosan. The best mechanical strength values of the blend fibers, 1.82 cN/d (dry state) and 0.81 cN/d (wet state), were obtained when PVA content was 20 wt % and the degree of deacetylation of chitosan was 90.2%. The strength of the blend fibers, especially wet tenacity could be improved further by crosslinking with glutaraldehyde. The water‐retention values (WRV) of the blend fibers were between 170 and 241%, obviously higher than pure chitosan fiber (120%). The structure analysis indicated that there are strong interaction and good miscibility between chitosan and poly(vinyl alcohol) molecular resulted from intermolecular hydrogen bonds. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2558–2565, 2001     

氯丁橡胶/丙烯酸酯橡胶共混研究

丙烯酸酯橡胶(ACM)的耐热老化性能和耐油性能较好,但力学性能较差。而氯丁橡胶(CR)的力学性能较高,耐温性能较差。两种橡胶并用可使力学性能和热老化性能有显著的提高。采用丙烯酸酯橡胶(ACM)和氯丁橡胶(CR)共混改性,通过偏光显微镜(×400)对共混物中两种橡胶的分散情况进行了分析。研究了CR/ACM共混物质量比、混炼和硫化工艺对共混物性能的影响,结果表明:当CR/ACM并用比在75/25时,采用过氧化二异丙苯、氧化锌、硫磺共硫化体系,白炭黑在混炼时分两次加入,硫化条件为165℃×10 MPa×30 min时,获得的CR/ACM共混物具有优异的力学性能和热老化性能。     

粉末羧基丁腈橡胶/聚氯乙烯共混胶的研制

将羧基丁腈橡胶(XNBR)乳液与聚氯乙烯(PVC)乳液共混,然后用胶乳凝聚成粉法凝聚成粉。研究了凝聚成粉的工艺及条件,考察了XNBR/PVC配比对产品性能的影响。结果表明,在隔离剂质量分数为3%～5%、凝聚温度为50～60℃、搅拌转速为300～400r/min的条件下,可制得成粉率在95.0%以上、贮存不黏结且性能良好的不同配比的粉末XNBR/PVC共混胶。     

Studies of chitosan. I. Preparation and characterization of chitosan/poly(vinyl alcohol) blend films

Various blending ratios of chitosan/poly (vinyl alcohol) (CS/PVA) blend films were prepared by solution blend method in this study. The thermal properties and chemical structure characterization of the CS/PVA blend films were examined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), and Fourier transform infrared (FTIR). Based upon the observation on the DSC thermal analysis, the melting point of PVA is decreased when the amount of CS in the blend film is increased. The FTIR absorption characteristic is changed when the amount of CS in the blend film is varied. Results of X‐ray diffraction (XRD) analysis indicate that the intensity of diffraction peak at 19° of PVA becomes lower and broader with increasing the amount of CS in the CS/PVA blend film. This trend illustrates that the existence of CS decreases the crystallinity of PVA. Although both PVA and CS are hydrophilic biodegradable polymers, the results of water contact angle measurement are still shown as high as 68° and 83° for PVA and for CS films, respectively. A minimum water contact angle (56°) was observed when the blend film contains 50 wt % CS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

甲基乙烯基硅橡胶并用体系研究

并用两种乙烯基含量不同的甲基乙烯基硅橡胶，添加适量含氢硅油，同时采用过氧化物和铂催化加成这两种硫化方式。可以得到高撕裂乙烯基硅橡胶。结果表明，当乙烯基质量分数为0．09％和0．13％的生胶并用比为50／50时，其撕裂强度比单独使用两种生胶时分别提高了46．9％和21．7％；两种硫化体系并用时，性能有了显著提高，超过了单独使用一种硫化方式的性能。