伊利石与炭黑并用对天然橡胶性能的影响

Effect of combination of illite and carbon black on properties of natural rubber

固定炭黑与伊利石总用量为50份,研究了炭黑与伊利石用量比(CB/illite)对天然橡胶(NR)的硫化特性、动/静态力学性能、抗臭氧老化性能和屈挠疲劳性能的影响。结果表明,与50份炭黑相比,40/10 CB/illite对硫化胶的拉伸强度几乎无影响,但撕裂强度显著下降,且伊利石与炭黑在该配比产生协同效应使胶料抵抗动态应变破坏的能力增强,表现为Payne效应明显减弱,能量耗散更低,体系更稳定。伊利石取代炭黑使胶料的焦烧时间增加,但硫程延长。当伊利石用量达20份时,硫化胶的拉伸强度、撕裂强度、硬度和100%定伸应力均明显下降,但断裂伸长率明显上升,表明伊利石的补强能力显著逊于炭黑。相比炭黑,伊利石可显著改善NR的耐臭氧老化能力。伊利石用量达20份时依然对NR的屈挠疲劳性能几乎无影响。

Fixed the total amount of carbon black and illite is 50 phr,the effects of the ratios of carbon black to illite(CB/illite)on the vulcanization,dynamic/static mechanical properties,ozone aging resistance and flexural fatigue properties of natural rubber(NR)were investigated.The results indicate that,compared with that of 50 phr CB,40/10 CB/illite shows little influence on the tensile strength of the vulcanizate,but the tear strength decreased significantly.Moreover,40/10 CB/illite shows a synergistic effect on the rubber compound and endows it a stronger ability to resist the dynamic strain failure,which is evidenced by an obvious weak Payne effect,a lower energy dissipation and a more stable system.The replacement of carbon black by illite make the scorch time of the rubber compound be increased,but the vulcanization process be prolonged.When the dosage of illite reaches 20 phr,the tensile and tear strengths,hardness and 100%tensile stress of the vulcanizate are significantly reduced,whereas the elongation at break is increased,suggesting the reinforcement of illite is significantly inferior to that of carbon black.Compared with that of carbon black,the ozone aging resistance of NR is improved markedly by illite,and 20phr illite still has no impact on the flexion fatigue performance of NR.