活化改性废硅橡胶与EPDM共混的研究

采用六亚甲基四胺与氯化铁/氯化亚铁混合物作为废硅橡胶的活化改性剂，以活化改性后的废硅橡胶与EPDM共混，研究活化改性剂添加方式及活化改性废硅橡胶用量对共混物物理性能的影响。结果表明，活化改性剂与废硅橡胶先预炼的活化效果较好，EPDM/活化改性废硅橡胶共混比为90/10时共混物的综合性能较好。     

硅橡胶/顺丁橡胶/乙丙橡胶共混材料的研究

针对硅橡胶具有较高耐热性．但力学性能差；三元乙丙橡胶（EPDM）力学性能较好，但互粘性较差；顺丁橡胶（BR）弹性好．但加工性能堇的特点，提出了将硅橡胶、三元乙丙橡胶与顺丁橡胶共混的方法，制成共混材料；再通过测定样品的性能，确定共混的最佳配比。结果表明：BR与EPDM、硅橡胶相客性较好，可达到共硫化；硅橡胶／BR／EPDM质量比为20／30／50时，共混物的物理机械性能和老化性能较好；用过氧化二异丙苯（DCP）／硫磺作硫化剂要好于用硫磺、过氧化二苯甲酰（BPO）和硫磺／BPO硫化剂。试样的耐热老化性能、邵尔A型硬度和扯断伸长率较好，其中样品的综合性能具备了硅橡胶、顺丁橡胶和三元乙丙橡胶的优点。     

硅橡胶/EPDM泡沫合金材料的结构与性能

分别采用电镜和激光共聚焦显微镜研究了硅橡胶／EPDM泡沫合金的结构均匀性和泡孔结构,并进行强伸性能,压缩性能和阻尼减震性能的研究,结果表明,采用硅烷偶联剂后,硅橡胶／EPDM共混物的分散均匀性较好;泡沫合金的密度小于0．55Mg.m^-3,泡孔均匀,平均孔径小于80um,且泡沫合金的拉伸强度,压缩性能和阻尼减震性能优于硅橡胶泡沫。     

A study on mechanical and thermal properties of silicone rubber/EPDM damping materials

Silicone rubber (SR) and ethylene‐propylene‐diene monomer (EPDM) blends were prepared for damping application. The mechanical and thermal properties of the blends are studied. With the increasing content of EPDM, the tensile strength is decreased but elongation at break is increased. By blending with EPDM, tan δ (at 35 to 200°C) of SR is enhanced. However, thermogravimetric analysis results showed the decrease in thermal stability. Scanning electron microscopy study showed the good filler dispersion of the blends with some large silica particles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Thermal stability and ablation properties of silicone rubber composites

Effects of incorporation of clay and carbon fiber (CF) into a high temperature vulcanized (HTV) silicone rubber, i.e., poly(dimethylsiloxane) (PDMS) containing vinyl groups, on its thermal stability and ablation properties were explored through thermogravimetric analyses (TGA) and oxy‐acetylene torch tests. Natural clay, sodium montmorillonite (MMT), was modified with a silane compound bearing tetra sulfide (TS) groups to prepare MMTS₄: the TS groups may react with the vinyl groups of HTV and enhance the interfacial interaction between the clay and HTV. MMTS₄ layers were better dispersed than MMT layers in the respective composites with exfoliated/intercalated coexisting morphology. According to TGA results and to the insulation index, the HTV/MMTS₄ composite was more thermally stable than HTV/MMT. However, addition of CF to the composites lowered their thermal stability, because of the high thermal conductivity of CF. The time elapsed for the composite specimen, loaded with a constant weight, to break off after the oxy‐acetylene flame bursts onto the surface of the specimen was employed as an index for an integrated assessment of the ablation properties, simultaneously taking into consideration the mechanical strength of the char and the rate of decomposition. The elapsed time increased in the order of: HTV < HTV/CF ≈ HTV/MMTS₄ < HTV/CF/MMTS₄ ≈ HTV/MMT < HTV/CF/MMT. This order was different from the increasing order of the thermal stability determined by TGA results and the insulation index. The decreased degree of crosslinking of the composites with MMTS₄ compared with that of the composite with MMT may be unfavorable for the formation of a mechanically strong char and could lead to early rupture of the HTV/MMTS₄ specimen. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Radiation synthesis of polysilane-modified graphene oxide for improving thermal conductivity and mechanical properties of silicone rubber

Functionalized graphene oxide (named GO-Si) was synthesized with graphene oxide and triethoxyvinylsilane (TEVS) using tetrahydrofuran solution by γ-ray irradiation. TEVS was successfully covered onto GO sheets, and the polysilane content on GO-Si was increased upon increasing the absorbed dose. The structures of GO-Si were verified by atomic force microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The resultant GO-Si was dispersed into α,ω-dihydroxypolydimethylsiloxane to prepare room temperature vulcanized silicone rubber composites (named SR/GO-Si) by solution casting. The dispersion of GO-Si was more uniform than that of GO. Compared to that of pure SR, the thermal conductivity of SR/GO-Si-1.95 composites was increased 1.5-fold, and its tensile strength and elongation at break increased 78.6 and 71.4%, respectively. It was expected that SR/GO-Si would have potential application as the thermal interface material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47776.     

硅灰石对陶瓷化硅橡胶性能的影响

研究硅灰石长径比和用量对硅橡胶性能的影响。结果表明:加入硅灰石,硅橡胶能够在高温烧蚀下形成坚硬、致密的陶瓷状壳体;随着硅灰石用量的增大,硅橡胶烧结体的弯曲强度增大,硅橡胶的阻燃性能和热稳定性提高;硅灰石用量相同时,添加普通硅灰石的硅橡胶烧结体的弯曲强度较大,添加针状硅灰石的硅橡胶的阻燃性能和热稳定性更好;针状硅灰石用量为60份时,硅橡胶的综合性能最佳。     

The effects of technological compatibility for silicone rubber/fluororubber blends

In this study, silicone rubber (SR) and fluororubber (FKM) blends were prepared and their properties were investigated. The crosslinking rate in the blends was increased with increase of SR content due to the silica filler existing into SR. As the content of FKM in the blends increases, the thermal decomposition temperature of the blends tended to increase and the thermal stability of 25/75 SR/FKM blend was higher than that of any other blends ratios. With the increase of FKM content in the blends, the contact angle of SR/FKM blends decreased and the surface energy increased owing to the change of the polarity of the surface. Dynamic mechanical analysis of 25/75 SR/FKM blend showed two transitions peak at −60.5 and −12.7°C, respectively, indicating the immiscibility. Fourier transform infrared attenuated total reflectance studies showed shifts in the peaks due to specific interactions in the blends, and field emission scanning electron microscopy (FE-SEM) studies revealed that the domain sizes of the blends come to be smaller with increasing FKM content. In the blend with 75 wt % of FKM, we observed that it is technologically compatible due to the increase of physical properties and the decrease of the domain size of FE-SEM in 25/75 SR/FKM blend. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

过氧化物高温硫化硅橡胶的热稳定性机理

研究了铁锡氧化物的复合物作为耐热添加剂的过氧化物高温硫化硅橡胶的热空气老化性能及其热稳定机理。热重法－差热分析说明铁锡氧化物的复合物可以提高硅橡胶的抗热氧化温度,Ｘ射线光电子能谱分析证明锡元素在硫化过程和热空气老化过程中被从Ｓｎ＾＋４还原到了Ｓｎ＾０,发生了多个电子转移的氧化－还原反应。     

4种网格结构模具用硅橡胶性能研究

分析了网格结构模具用4种不同的室温硫化硅橡胶的性能结果表明,该4种硅橡胶均具有较小的线收缩率及较长的凝胶时间,但加成型室温硫化硅橡胶较缩合型硅橡胶具有突出的室温力学性能、热稳定性及热线胀性能,完全满足用于制作网格模具的硅橡胶要求.     

可瓷化硅橡胶的制备与性能

以硅橡胶为基材、低软化点玻璃粉为成瓷填料,采用双辊开炼的方法制备一种可瓷化硅橡胶复合材料。研究玻璃粉用量对复合材料拉伸性能及瓷化性能的影响。结果表明:玻璃粉用量对复合体系的拉伸强度影响较小,在6~7 MPa间波动,对体系的断裂伸长率有显著影响,从约180%下降到110%;玻璃粉用量较大时,瓷化温度从750℃迅速下降到600℃;玻璃粉用量增加可提高低温瓷化物的抗热冲击性。扫描电镜观察结果表明:瓷化物内部存在大量气孔,导致试样的致密性均较差。     

Preparation and heat resistance of hollow glass microbead/silicone rubber composite coating

Hollow glass microbead/silicone rubber composite coatings were prepared to improve the heat-resistance and mechanical properties of silicone rubber-based composites, using CE modified SR as the matrix and HGM as the filler. The microscopic morphology and thermal stability of the composites were characterized by scanning electron microscopy (SEM) and thermogravimetric analyzer (TGA), respectively. The results showed that the thermal stability of the composites increases with the increase of filler content. For the composite sample with a HGM mass content of 16.7%, the initial decomposition temperature (T₅) is 408°C, which is 84°C higher than that of silicone rubber. The low density and high sphericity of HGM make it easier to uniformly disperse in the polymer matrix. In addition, compared to silica, which is commonly used as an inorganic filler, the lower thermal conductivity of HGM is also beneficial for achieving better thermal shielding effect. It is confirmed that the insufficient thermal stability of the polymer matrix above 400°C can be compensated for by the properly dispersed inorganic fillers. Therefore, the thermal stability of the composite is improved by the synergistic effect of modified heat-resistant matrix and inorganic filler.     

Adhesion properties and thermal degradation of silicone rubber

Silicone rubber is suitable for the thermal insulator of the rocket motors owing to its heat resisting properties as well as its excellent elasticity and restoring force. However, the adhesion properties of the silicone rubber should be improved greatly to be used as the thermal insulator because of its poor adhesiveness coming from the low surface tension. Functional groups were incorporated through copolymerization to the silicone rubber to induce chemical reaction with the functional groups in the propellant/liner components to enhance the adhesion properties. Peeling tests results disclosed that the incorporation of amine groups was the most efficient for the adhesiveness enhancement and that addition of carbon black improved the adhesiveness still more. Stability against thermal degradation of the silicone rubber was examined by measuring the activation energy through the thermogravimetric analysis. The results revealed that the compounding of the Cloisite® clays boosted up the thermal stability of the silicone rubber much more greatly than that of carbon black. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2782–2787, 2007     

硅橡胶在电气绝缘方面的应用进展

简述了国内外硅橡胶(高温硫化型硅橡胶、室温硫化型硅橡胶、液体硅橡胶等)在电气绝缘方面的应用情况。     

三元乙丙海绵橡胶垫热老化寿命之研究

三元乙丙海绵发泡产品在越来越多的领域里得到了推广和应用。文中主要针对三元乙丙橡胶（EPDM）海绵发泡蛰板的热老化使用寿命进行了分析、研究并计算。研究结果表明,EPDM海绵发泡橡胶垫板在40℃以下性能下隆20%时,产品仍可正常使用43年。     

导热硅橡胶的研究进展

综述了填充型导热橡胶的导热机理和各类导热填料的导热特性,介绍了提高导热硅橡胶导热性的途径。     

Electrically insulating ZnOs/ZnOw/silicone rubber nanocomposites with enhanced thermal conductivity and mechanical properties

In this work, hybrids of surface modified zinc oxide spherical (ZnOs) nanoparticles and tetrapod‐shaped whiskers (ZnOw) were incorporated into the silicon rubber (SR) to prepare the ZnOs/ZnOw/SR nanocomposites. The incorporation of the ZnOs/ZnOw facilitated the formation of three‐dimensional thermally conducting network. It was found that the thermal conductivity of the ZnOs/ZnOw/SR reached up to 1.309 W m^?1 K^?1 when the ZnOs/ZnOw content was 20 vol % (V_m‐ZnOs:V_ZnOw = 7:3), which was nearly 6.5 times that of the pristine SR. The dielectric and resistivity measurements showed that the incorporation of the ZnOs/ZnOw hybrids did not cause much change in the electrical properties. In addition, the results show that the tensile strength of ZnOs/ZnOw/SR nanocomposites is higher than that of pristine SR. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46454.     

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。     

硅橡胶／纳米铜复合材料的结构与性能研究

采用机械混炼法制备了一种新型的宫内节育器材料——硅橡胶／纳米铜（SiR／nano-Cu）复合材料。利用扫描电子显微镜（SEM）和X射线衍射仪（XRD）观察了复合材料的组织结构,系统研究了nano-Cu含量对复合材料的力学性能、热稳定性能和吸水性能的影响。结果表明,纳米铜在复合材料的分散比较均匀,呈纳米级分布,只有极少数发生团聚。nano-Cu能提高复合材料的硬度,在高添加量时,材料的拉伸强度稍稍下降,但撕裂强度得到了很好的保持。随着纳米铜含量的增大,复合材料的热稳定性和吸水性能大大提高。     

硅橡胶／三元乙丙橡胶泡沫合金的研制

研究了硅橡胶／三元乙丙橡胶（Ｑ／ＥＰＤＭ）共混,发泡的配方与成型工艺,对补强剂,发泡剂,硫化剂,成型温度,时间等因素对泡沫材料的密度硬度等性能的影响进行了研究。