烷氧基封端107硅橡胶的合成及性能研究

采用不同烷氧基封端剂对α,ω-二羟基聚二甲基硅氧烷(107硅橡胶)进行封端制得烷氧基封端107硅橡胶。以此为基胶,加入气相法白炭黑、催化剂等制得脱醇型室温硫化硅橡胶胶粘剂。考察了封端剂种类及用量对烷氧基封端107硅橡胶性能的影响;考察了催化剂、气相法白炭黑种类及用量对胶粘剂性能的影响。结果表明,采用甲基三甲氧基硅烷和乙烯基三甲氧基硅烷封端的107硅橡胶配制的胶粘剂的综合性能较好;传统有机锡催化剂(二月桂酸二丁基锡)会导致胶料贮存后不硫化,不适合于封端107硅橡胶体系;采用经过改性的有机锡为催化剂,具有较快的催化速率,得到的胶粘剂的力学性能较好,且胶料贮存稳定;而以钛配合物为催化剂能赋予胶料较好的透明性和耐黄变性能。亲水型气相法白炭黑可赋予胶料良好的增稠触变性;疏水型气相法白炭黑可赋予胶料良好的透明性;而经过结构化处理的疏水型气相法白炭黑,则可赋予胶料良好的流动性和优异的透明性。     

硅烷偶联剂在气相白炭黑表面处理中的应用研究

本文考察了几种不同硅烷偶联剂对气相白炭黑的表面处理效果.对处理前后的气相白炭黑作了FT-IR分析,并用正交试验法考察了处理剂类型、处理时间及处理温度对产品疏水性的影响.结果表明,用18％的HMDS作处理剂,将气相白炭黑在90℃条件下处理4h,所得的疏水性气相白炭黑能很好改善RTV-2硅橡胶的工艺性能和力学性能;另外,采用胶料中直接混合的方式HMDS也能有效改善胶料工艺性能.     

气相白炭黑的比表面积与表面特性对硅橡胶补强效果的影响

探讨了气相白炭黑的比表面积和表面特性对硅橡胶力学性能的影响,同时采用扫描电镜和溶胀法分别研究了不同表面特性白炭黑补强硅橡胶的拉伸断面形貌和交联密度。结果表明：随着疏水性白炭黑比表面积的增加,硅橡胶拉伸强度和断裂伸长率增加;对比发现,疏水性白炭黑的补强效果优于亲水性白炭黑,这是由于疏水性白炭黑在橡胶基体中分散更加均匀,而且疏水性白炭黑补强硅橡胶的交联密度更大。     

硅橡胶补强填料的研究进展

纯硅橡胶的机械强度很低,添加补强填料是提高硅橡胶物理机械性能的主要手段。简要介绍了近年来有关气相法白炭黑、沉淀法白炭黑、短纤维与碳纳米管、纳米碳酸钙在硅橡胶补强中的应用研究概况。     

耐高温甲基乙烯基硅橡胶

本发明公开了一种耐高温甲基乙烯基硅橡胶,包括配方、制备工艺方法。本发明采取在以甲基乙烯基硅生胶为橡胶原料的配方中,添加氧化铈、聚酰亚胺提高耐热温度,添加羟基硅油、二甲基硅油,硅烷偶联剂提高耐油性能,添加沉淀法白炭黑、气相法白炭黑提高抗撕裂强度,添加石英粉、硅藻土提高拉伸强度,     

影响HTV硅橡胶撕裂强度的因素

考察了白炭黑种类、羟基硅油用量、含氢硅油用量以及不同乙烯基含量生胶并用对热硫化(HTV)硅橡胶撕裂强度的影响。结果显示,气相法白炭黑的补强效果强于沉淀法白炭黑,且比表面积越大,硅橡胶的撕裂强度越高;随着羟基硅油加入量的增加,硅橡胶的撕裂强度先增后趋于稳定;含氢硅油的用量对HTV硅橡胶的撕裂强度基本没有影响;高乙烯基含量生胶和低乙烯基含量生胶并用能显著提高HTV硅橡胶的撕裂强度。较佳配方是:166 g 110-0生胶,4 g 112生胶、80 g QS-102气相法白炭黑、8.5 g羟基硅油、1.0 g含氢硅油、0.5 g乙烯基硅油,此时,HTV硅橡胶的撕裂强度达到21 KN/m。     

高炉煤气蝶阀硅橡胶密封圈的研制

介绍了高炉煤气蝶阀硅橡胶密封圈的研制。高炉煤气蝶阀硅橡胶密封圈胶料的配方确定为：甲基乙烯基硅橡胶　５０ ;甲基苯基乙烯基硅橡胶　５０ ;气相法白炭黑　３０ ;沉淀法白炭黑　４０ ;三氧化二铁　５ ;氧化锌　５ ;二苯基硅二醇　２ 。胶料混炼分二段进行,一段混炼胶料经２００ ℃×１ ｈ 的热处理后再进行二段混炼。一段硫化条件（１０ Ｍ Ｐａ） 为：１６０ ℃×１５ ｍｉｎ ;二段硫化工艺为：室温１ ｈ １５０ ℃１ ｈ ２００ ℃１ ｈ ２５０ ℃５ ｈ 硫化完毕。胶料性能满足设计要求,成品耐热老化性和耐化学稳定性好。     

新型无定形白炭黑SilOaTM在HTV硅橡胶中的应用

简要介绍了罗地亚公司近期推出的SilOa^TM系列无定形白炭黑的特点，着重比较了SilOa^TM72X、沉淀法白炭黑及气相法白炭黑在热硫化硅橡胶中的应用特点。结果表明，SilOa^TM72X在物化性能上介于气相法白炭黑和沉淀法白炭黑之间；应用在硅橡胶中，其补强性能优于普通的沉淀法白炭黑，接近比表面积为150m^2／g的气相法白炭黑；电学性能也相似。而且，SilOa^TM72X具有更好的操作性能；在提高硅橡胶撕裂强度的同时，赋予硅橡胶优异的抗压缩永久变形性。     

红外光谱和拉曼光谱法研究白炭黑的微观结构

用红外光谱和拉曼光谱分析沉淀法白炭黑和气相法白炭黑的微观结构。结果表明：与气相法白炭黑相比,沉淀法白炭黑表面羟基含量相对较高;未经热处理的沉淀法白炭黑表面覆盖结合水分子,随着处理温度的升高,沉淀法白炭黑表面先失去羟基结合水分子,然后发生羟基缩合反应,直至最后失去所有羟基,形成Si—O—Si网络结构;气相法白炭黑未经热处理时即可明显观察到羟基的存在,且处理温度对其结构影响不明显,这可能是沉淀法白炭黑与气相法白炭黑生产工艺不同造成的。     

耐热型热硫化混炼胶的研制

以甲基乙烯基硅橡胶为生胶,添加气相法白炭黑、耐热添加剂等制得耐热型热硫化硅橡胶,研究了生胶中羟基含量、白炭黑种类、白炭黑处理剂种类以及耐热剂种类对硅橡胶耐热性能的影响。结果表明,当采用羟基质量分数≤15×10^-6、乙烯基摩尔分数为0.19%的甲基乙烯基硅橡胶生胶时,其抗降解表现更好;不同类型白炭黑在不同的老化温度下对硅橡胶的影响不同,225℃及以下温度条件下,亲水型白炭黑的耐热效果优于疏水型白炭黑,225~300℃及以上温度条件下,疏水型白炭黑更优;在白炭黑处理剂对硅橡胶耐老化影响方面,采用聚二甲基二苯基硅氧烷RP140PH比常规低黏度羟基硅油和六甲基二硅氮烷更好;耐热剂对硅橡胶体系耐老化效果提升极为明显,其提升效果由高到低依次为AD105、AD111、AD104、AD110。     

Effect of surface chemistry and morphology of silica on the thermal and mechanical properties of silicone elastomers

In this study, high‐temperature vulcanized silicone rubbers (HTV‐SRs) using fumed silica (FSi), precipitated silica (PSi), and modified precipitated silica (MPSi) as reinforcing fillers were prepared. The effect of morphology and surface chemistry of the silica on the thermal and mechanical properties of the resultant silicone rubbers was investigated using curing rheometer, scanning electron microscopy, mechanical test, and dynamic mechanical analysis. The thermo‐oxidative stability and solvent resistance of the vulcanized silicone rubbers were further evaluated via heat ageing test, extraction, and swelling experiments. It is shown that the mechanical properties (tensile modulus and tensile strength) of the as‐prepared HTV‐SRs are in the order of FSi > PSi > MPSi, which could be attributed to the molecular interaction between the filler and the matrix. FSi has the highest surface area, which enhances the hydrogen bonding interaction between the filler and the silicone matrix; while MPSi, in which part of Si? OH groups have been consumed during modification, shows the weakest interaction among the three. The filler–matrix interaction could also explain the lowest swelling and sol fraction in FSi‐filled HTV‐SR, and the low viscosity and good processibility of PSi‐ and MPSi‐filled HTV‐SR. Furthermore, it is also shown that the MPSi‐filled HTV‐SR exhibits the highest retention of mechanical properties after thermal aging at 250 °C for 24 h, which could be attributed to the lowest acidity of the fillers. The possible mechanism for acid catalyzed hydrolytic chain scission and intramolecular chain backbiting has been proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46646.     

Synthesis of reusable silicone foam containing carbon nanotubes for oil spill remediation

The aim of this work is the synthesis of silicone foam containing carbon nanotubes (CNT) for oil spills remediation. The CNT silicone foams are obtained by foaming a solution of a silicone matrix with CNT filler (5.6 wt %) in presence of a Sn‐based catalyst. Pristine and functionalized CNT have been used. All the obtained materials present a foam morphology with an open cell structure. Each foam is tested in four commonly used oils (kerosene, pump oil, naphtha, and crude oil). Among all, the foam filled with pristine CNT shows the highest sorption capacity (800 wt % in virgin naphtha) and an excellent reusability (up to 10 times). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46067.     

耐高温强碱有机硅消泡剂的研制

实验从消泡活性物的研制入手,通过单因素实验和L16(45)正交试验确定了影响消泡剂抑泡性能的条件,优选合成工艺条件为:m(甲基硅油):m(羟基硅油)=4:1,w(MQ硅树脂)=10%,M/Q(MQ硅树脂单官能链节Me3SiO0.5和四官能链节SiO4/2的摩尔比)为0.8,w(疏水白炭黑)=8%,w(氢氧化钾)=2%,交联反应温度和时间分别为150℃和4 h.用自制的两种硅聚醚为主乳化剂对上述消泡活性物进行了乳化,制得耐高温强碱有机硅乳液消泡剂.     

聚硅氧烷消泡剂的失活和再生机理

介绍了聚硅氧烷消泡剂失活和再生的现象，分析了失活过程中消泡剂分散体粒径大小和分布，泡沫体系的表面张力、接触角、硅油铺展层的厚度以及泡沫膜的结构和状态，结果表明：硅油组成的改变、硅油和疏水二氧化硅微粒的分离、消泡剂分散体粒径的变小、铺展油层的消失和白色絮凝物的出现导致消泡剂失活，其中二氧化硅硅粒-硅油的分离和泡沫膜上硅油铺展油层的消失是主要因素。失活的消泡剂中加入硅油，消泡活性可再次恢复，这主要是由于消泡剂分散体粒子中的硅油-二氧化硅硅粒比例达到最佳的状态并在泡沫膜上又形成了新的具有消泡活性的硅油铺展油层。     

离子束表面沉积对泡沫硅橡胶性能的影响

采用铜离子束辅助增强沉积技术对泡沫硅橡胶进行表面改性处理，分析由此引起的材料密度、硬度及电阻率的变化，研究了表面沉积导电薄膜对泡沫硅橡胶拉伸性能、压缩应力－应变性能及压缩永久变形的影响。结果表明，采用铜离子束辅助增强沉积技术，在不影响材料力学性能的前提下，可改进泡沫硅橡胶的抗静电性能。     

有机硅泡沫塑料的研究进展（上）

以２８篇文资料综述了近２０年来国内外关于有机硅泡沫塑料的研究进展,并介绍了有机硅泡沫塑料的制备方法。     

有机硅泡沫塑料的研究进展（下）

以２８篇文献综述了近２０年来国内外关于有机硅泡沫的研究进展，并介绍了有机硅泡沫塑料的制备方法。     

硅橡胶泡沫材料技术及应用

综述了近年来硅橡胶泡沫材料的研究进展, 着重从硅橡胶泡沫材料的制备及发泡机理、功能性硅橡胶泡沫材料以及硅橡胶泡沫材料的应用等方面进行介绍。并指出硅橡胶泡沫有望成为未来发泡材料的发展方向之一。     

Kinetics of the thermal degradation and thermal stability of conductive silicone rubber filled with conductive carbon black

The kinetics of the thermal degradation and thermal stability of conductive silicone rubber filled with conductive carbon black was investigated by thermogravimetric analysis in a flowing nitrogen atmosphere at a heating rate of 5°C/min. The rate parameters were evaluated by the method of Freeman–Carroll. The results show that the thermal degradation of conductive silicone rubber begins at about 350°C and ends at about 600°C. The thermal degradation is multistage, in which zero‐order reactions are principal. The kinetics of the thermal degradation of conductive silicone rubber has relevance to its loading of conductive carbon black. The activation energies are temperature‐sensitive and their sensitivity to temperature becomes weak as temperature increases. In addition, the conductive silicone rubber filled with conductive carbon black has better thermal stability than that of silicone rubber without any fillers. Also, conductive silicone rubber filled with conductive carbon black has better thermal stability than that of silicone rubber filled with the same amount of silica. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1548–1554, 2003     

Silicone rubbers for dielectric elastomers with improved dielectric and mechanical properties as a result of substituting silica with titanium dioxide

One prominent method of modifying the properties of dielectric elastomers (DEs) is by adding suitable metal oxide fillers. However, almost all commercially available silicone elastomers are already heavily filled with silica to reinforce the otherwise rather weak silicone network and the resulting metal oxide filled elastomer may contain too much filler. We therefore explore the replacement of silica with titanium dioxide to ensure a relatively low concentration of filler. Liquid silicone rubber (LSR) has relatively low viscosity, which is favorable for loading inorganic fillers. In the present study, four commercial LSRs with varying loadings of silica and one benchmark room-temperature vulcanizable rubber (RTV) were investigated. The resulting elastomers were evaluated with respect to their dielectric permittivity, tear and tensile strengths, electrical breakdown, thermal stability and dynamic viscosity. Filled silicone elastomers with high loadings of nano-sized titanium dioxide (TiO₂) particles were also studied. The best overall performing formulation had 35 wt.% TiO₂ nanoparticles in the POWERSIL® XLR LSR, where the excellent ensemble of relative dielectric permittivity of 4.9 at 0.1 Hz, breakdown strength of 160 V µm^?1, tear strength of 5.3 MPa, elongation at break of 190%, a Young’s modulus of 0.85 MPa and a 10% strain response (simple tension) in a 50 V μm^?1 electric field was obtained.