贮存硬化对脱蛋白天然橡胶性能影响的初探

Effect of storage hardening on the performance of deproteinized natural rubber

通过对比刚生产和自然贮存半年发生贮存硬化的LPNR制备的改性胎肩垫胶,研究天然橡胶的蛋白质含量在0.06%~0.5%时的物理性能、硫化力学性能。结果表明,其压缩温升、球性回弹、tanδ、门尼黏度、正硫化时间、拉伸强度、拉断伸长率等加工特性变化不大,撕裂强度、屈挠性能在蛋白质含量0.5%时变化不大,随着蛋白质含量进一步降低,撕裂强度、屈挠性能明显提高,蛋白质含量在0.25%时撕裂强度、屈挠性能达到最大,撕裂强度为97.8 kN/m,屈挠(级/3.0×10^5万)为12.5次万/6级,蛋白质含量在0.06%时略有下降;与进口20号胶(TQ927)相比,LPNR改性垫胶的定伸应力、撕裂强度和硬度较TQ927有一定的下降,其屈挠、温升、回弹性、tanδ、拉伸强度、拉断伸长率有明显的改善。

This article compares the modified shoulder filler mat prepared by storage-hardened LPNR that has just been produced and naturally stored for six months.To study the physical and chemical properties of natural rubber and the mechanical properties of vulcanizates with a protein content of 0.06%~0.5%.The result showed that the processing and curing characteristics,such as Mooney viscosity,scorch time,curing time,fixed elongation,tensile strength,elongation at break,permanent deformation,hardness,compression temperature rise,ball rebound,tanδand so on,didn’t change.The tear strength and flexural performance did not change much when the protein content was 0.5%.As the protein content was further reduced,the tear strength and flexion performance were significantly improved.The tear strength and flexion performance reached the maximum when the protein content was 0.25%.The tear strength was 97.8 kN/m,flexion(per level/3.0×10^5)was 12.5 times per million/six level,and the protein content was slightly decreased at 0.06%.Compared with imported No.20 glue,the tensile stress,tear strength and hardness of LPNR modified sizing rubber are somewhat lower than that of TQ927,but its tensile strength,tensile elongation at break,tanδ,flexing performance,compression of heat and rebound have obvious improvement.