用差热分析法评选CR防老剂

用差热分析法测定氯丁橡胶(CR)的氧化峰峰温,对 11种防老剂进行了评选,求得氧化反应表观活化能△E,频率因子A,反应速率常数K_T,并用Doyle公式求取氧化反应诱导期t_i。实验证明,K_T和 t_i能够表征防老剂的防老化效果,t_i可用于初步估算 CR的贮存时间,所得结果与烘箱老化实验具有良好的一致性。防老剂1010、1076和甲叉-4426-S是 CR防老化效果较为突出的防老剂。

氯丁橡胶接枝甲基丙烯酸丁酯的热降解动力学

用热重法和微商热重法研究了甲基丙烯酸丁酯与氯丁橡胶的接枝共聚物（CR—g—BMA）的热降解过程。结果表明，该接枝共聚物热降解过程分3个温度范围完成，第1热降解温度为553～653K；第2热降解温度为653～793K；第3热降解温度大于793K，其中第3热降解温度的终止温度明显受升温速率的影响。CR—g—BMA的第1温度范围热分解过程符合Avrami—Erofeev降解机理，即随机成核和随后生成机理，热分解过程平均活化能为234．9kJ／mol；对于热降解的积分机理函数，其频率因子的自然对数为33．48；对于热降解的微分机理函数，其频率因子的自然对数为48．90。

氯丁橡胶中组分含量分析

通过实验介绍了硫化氯丁橡胶中各组分含量分析的系统方法。氯丁橡胶(CR)热分解过程较复杂,不能直接从热重分析(TG)曲线读出各组分含量。笔者用TG分析法与传统化学分离、分析法相结合,成功地分析了硫化CR中各组分含量,推导出计算CR含量的公式。该方法操作方便,分析结果准确,能满足产品开发和生产质量控制的需要。

橡胶密封膜的失效分析

用红外光谱和电子能谱对某破损橡胶密封膜进行了分析 ,分析结果表明 ,橡胶密封膜为氯丁橡胶和丁腈橡胶并用胶 ,与外层胶材质要求不符 。

氯丁橡胶的市场分析

分析了国内外氯丁橡胶(CR)的供需现状及发展前景。

氯丁橡胶胶管内层胶热油老化前后的扣压应力-应变模拟

以氯丁橡胶为胶管基胶,采用非线性有限元分析软件ABAQUS对胶管扣压内层胶进行有限元分析,并建立胶管扣压模拟,模拟热油老化前后内层胶在扣压后不同路径下Mises应力、应变能密度(SED)、应力集中单元SED及扣压过程中静刚度的变化。结果表明,同一路径下,老化前Mises应力及SED均大于老化后;当扣压位移量相同时,老化前的静刚度大于老化后,同一单元老化前的SED大于老化后。

Fatigue Life Estimation of an Elastomeric Pad by ε-N Curve and FEA

Failure analysis and fatigue life prediction are very important in the design procedure to assure the safety and reliability of rubber components. The fatigue life of a railway elastomeric pad is predicted by combining the test of material properties and finite element analysis (FEA). The specially developed chloroprene rubber material’s fatigue life equation is acquired based on uniaxial tensile test and fatigue life tests performed on the dumbbell specimens of the chloroprene rubber. The same chloroprene rubber was developed at Indian Rubber Manufacturer’s Research Association, Thane. The strain distribution contours and the maximum total principal strains of the elastomeric pad at different compressive loads are obtained using finite element analysis method. The software used for the FEA was ANSYS. The three parameter nonlinear hyperelastic Mooney-Rivlin Model and plane 182 elements were used for finite element analysis. The critical region cracks prone to arise are obtained and analysed. Then the maximum first principal elastic strain was used as the fatigue damage parameter, which is substituted in the chloroprene rubber’s fatigue life equation, to predict the fatigue life of an elastomeric pad in the number of cycles at different compressive loads. The results were compared with the technical requirements given by Indian Railway’s Research Designs and Standards Organization. These requirements were achieved up to certain extents. The results were also compared with the data available in the literature and a similarity was observed between the results acquired and literature data. In short, the proposed fatigue life prediction method can shorten the product design cycle, decrease the design and product cost remarkably and improve the quality of an elastomeric pad.

基于PCA-BP网络的氯丁橡胶门尼黏度预测

为了准确预测氯丁橡胶门尼黏度,采用氯丁橡胶生产工艺机理及数据分析结果相结合的方法,选取影响门尼黏度的主要因素,提出了一种基于PCA-BP神经网络的氯丁橡胶门尼黏度的软测量预测方法,建立了双隐含层的神经预测网络模型。通过训练,确定网络结构为6-5-13-1。仿真显示,最大相对误差为4.1%,平均相对误差为1.8%,最大绝对误差为4.389,误差在允许的范围内,满足生产要求。