炭黑和白炭黑填充硫化胶的湿摩擦差异性分析

研究不同负荷和速度下炭黑和白炭黑填充硫化胶的湿摩擦因数,并对其摩损表面进行了扫描电子显微镜和透射电镜表征。结果表明：炭黑填充硫化胶的湿摩擦因数随着速度的增大呈线性下降,随着负荷的增大略有降低,而白炭黑填充硫化胶的湿摩擦因数随着速度的增大呈非线性下降,随着负荷的增大先迅速下降后缓慢降低;白炭黑填充硫化胶摩擦面橡胶膜较薄,裸露白炭黑粒子,过渡区摩擦力较大,不能忽略;炭黑填充硫化胶表面的橡胶膜厚度较大,表面炭黑粒子被橡胶大分子覆盖,过渡区摩擦力小,可以忽略。     

白炭黑胎面胶配方中促进剂DPG的替代试验研究

研究在典型的白炭黑胎面胶配方中用促进剂DPT和TATD替代促进剂DPG的应用效果。结果表明:虽然促进剂DPG高温裂解会产生危害人体健康和环境的苯胺,但其在白炭黑胎面胶配方中的综合性能优势比较明显;促进剂DPT替代促进剂DPG在硫化体系上需要进行适当调整,同时要注意其对胶料门尼粘度、拉伸强度及拉断伸长率等的影响;促进剂TATD替代促进剂DPG的难度较大,替代后混炼胶的加工性能和硫化胶的物理性能都发生了比较明显的变化;在白炭黑胎面胶配方中促进剂DPG替代不能进行简单的品种更换,同时需对配方其他组分进行优化调整。     

Silica masterbatches produced with liquid phase mixing Part IV. Volume variation and SEM observations upon stretching

The volume of vulcanizates changes slightly during stretching. Generally, dilatometry and hydrostatic weighing methods are used to measure volume change. Vacuole formation and polymer crystallization are the two main causes of the volume changes, and these are attributed to the separation of polymer from the filler surface and the alignment of polymer molecules, respectively. The relative volume change, ΔV/V, of four different vulcanizates based on a blend of SSBR (solution polymerized styrene-butadiene rubber) and BR (cis-polybutadiene rubber) has been plotted against elongation, ε. The relative volume change of an eco-visco-elastomer-composite (EVEC) compound produced by a continuous liquid phase mixing process was much less than that of a dry-mixed counterpart, especially after normalizing by stress, σ. Scanning electron microscopy (SEM) was utilized to observe the emergence of vacuoles during stretching, and obtain information on their relative size and distribution without the need for replication or ion sputter coating. SEM images also showed that the dispersion of silica in EVEC is better and the number of vacuoles is much less than in the dry-mixed compounds, characterizing a “denser” vulcanizate.     

辐射预硫化炭黑/白炭黑天然橡胶胶料性能对比研究

对炭黑和白炭黑分别填充的天然橡胶(NR)胶料进行电子辐射预硫化,研究辐射预硫化对胶料的结合胶含量、门尼粘度和硫化特性及硫化胶的物理性能和动态性能的影响。结果表明,辐射预硫化能提高胶料的结合胶含量、门尼粘度和硫化速度,对两种硫化胶的应力应变、生热和磨耗等性能产生不同的影响,并能显著抑制填料在橡胶基体内网络结构的形成,降低胶料的滞后损失。     

防老剂对过氧化物硫化体系氢化丁腈橡胶性能的影响

研究防老剂对过氧化物硫化体系氢化丁腈橡胶(HNBR)性能的影响。结果表明:防老剂种类可以显著影响过氧化物硫化体系HNBR硫化胶的交联密度,防老剂ZMTI可显著消耗过氧化物自由基,阻碍过氧化物硫化反应的进行,使采用防老剂ZMTI的硫化胶的交联密度减小,单用防老剂445或ODA对硫化胶的交联密度影响相对较小;单用防老剂445的HNBR硫化胶的定伸应力最大,弹性最好,压缩永久变形和损耗因子最小,防老剂445是非常适合过氧化物硫化体系HNBR的防老剂。     

硅烷偶联剂对白炭黑填充溴化丁基橡胶/天然橡胶并用胶性能的影响

试验研究硅烷偶联剂Si69,Si75和KH560对白炭黑填充溴化丁基橡胶(BIIR)/天然橡胶(NR)并用胶性能的影响。结果表明:随着硅烷偶联剂Si75或KH560用量的增大,胶料的挤出膨胀率呈增大趋势,门尼粘度和F;减小,Payne效应减弱,定伸应力和拉伸强度呈增大趋势,拉断伸长率和撕裂强度呈减小趋势,加工性能和老化后耐屈挠性能改善;硅烷偶联剂Si75和KH560能够明显改善白炭黑填充BIIR/NR并用胶的加工性能和老化后的耐屈挠性能。     

磨损轮胎的性能研究

使用4个规格、不同剩余花纹深度的磨损轮胎,通过实车测试研究磨损率对轮胎性能的影响。结果表明,随着磨损率增大,轮胎的滚动阻力系数呈先增大后减小的趋势,接地面积呈先减小后增大的趋势,干地制动性能呈先降低后提高的趋势但变化较小,湿地制动性能明显降低。