炭黑N134在不同橡胶基体中的分散及其混炼工艺调控

Dispersion of Carbon Black N134 in Different Rubber Systems and Its Mixing Process Regulation

以炭黑N134作为填料,对比了异戊橡胶、丁苯橡胶及仿生橡胶3种体系下混炼工艺对硫化胶性能的影响,并针对仿生橡胶体系炭黑分散度低的问题,对混炼工艺进一步优化,从而提高分散度和动静态性能.结果表明,在所研究的密炼时间范围内,随着密炼时间的延长,异戊橡胶体系和丁苯橡胶体系的分散等级由原本的1级左右提升至6级以上.但延长密炼时间并未明显提升仿生橡胶体系的炭黑分散度.针对该问题引入塑炼和包辊工艺,仿生橡胶炭黑分散性明显提高.随炭黑分散等级的增加,3种橡胶体系的伸张疲劳性能均得到了较大改善.其中仿生橡胶生胶经塑炼后,门尼黏度和重均分子量均明显下降,表明塑炼对于增强胶料的加工性能有明显作用.相同炭黑混炼时间下,随着塑炼时间的延长,硫化胶佩恩效应也增强,这主要是由于炭黑分散程度的提高使得炭黑与橡胶基体的有效接触面积增加,进而在一定程度上增加了界面结合胶的含量.

The influence of mixing process on the properties of carbon black(CB,N134)reinforced isoprene rubber,styrene butadiene rubber and bionic rubber after cure was studied.Considering that the dispersion of CB in bionic rubber is poor compared to that in the other two systems,a new processing routine was designed to improve the dispersity of CB in bionic rubber,and the results show a good dispersity of CB and an enhanced performance of bionic rubber.Our study indicates that,with increasing internal mixing time,the dispersity of CB in isoprene rubber and styrene butadiene rubber is improved from about 1 grade to higher than 6 grade,while that in bionic rubber still remains a low grade(around 1 grade).Further increasing the internal mixing time does not greatly improve the disper⁃sity of CB in bionic rubber system.To solve this,mastication and mill banding were introduced and the dispersion of CB was greatly improved in bionic systems.As expected,with increasing the dispersity of CB in rubber systems,the tensile fatigue life was enhanced,as verified by all the three studied rubber systems.For bionic rubber,a certain time of mastication will decrease the Mooney viscosity and the molecular weight of gum,leading to an enhanced processability.Moreover,Payne effect in vulcanized bionic rubber was also increased with increasing the mastication time.This is probably due to the fact that the improvement of dispersion of CB in rubber matrix increases the specific area of CB agglomerates,which brings more bound rubber to enhance the interfacial adhesion between fillers and rubber matrix.