Study On Aramid Short Fibre & Pulp As NR Composite Reinforcing Filling Used In Tyre

Short fiber-rubber composite (SFRC) is widely used in the tire industry. Application of SFRC become the most important technical approach to improve quality of tyre.Many technologies of aramid short fibre & pulp as natural rubber (NR) composite reinforcing filling have been developed for some excellent characteristics of aramid short fiber, such as high modulus, high strength & low density. Study on aramid short fibre & pulp as NR composite reinforcing filling used in tyre could find an effective way to develop tyre products of our country.In this paper, the effect of mechanical properties of NR composite which reinforced with two type of aramid short fiber predispersion, Sulfron3000 & EE, was studied. At the same time, test and analysis on dispersibility of aramid short fibre in rubber matrix and interface adhesion between rubber matrix and short fibre were also made.The results revealed that:Firstly, as aramid short fiber predispersion, both Sulforn3000 & EE had effectively improved dispersibility in rubber matrix. Both of them enhanced the mechanical properties of NR composite greatly.Secondly, there was some difference between the effect of Sulfron 3000 and EE as reinforcing filling on the mechanical properties such as tensile strength, tearing strength, elongation at break, shore A hardness and Akron abrasion of NR composite. Thirdly, splits and fibrillates of PPTA pulp could not only be helpful to improve adhesion between short fibre and rubber matrix, but also caused hardness for pulp to disperse into rubber matrix .As a result, difference of dispersibility and adhesion between EE & Sulfron 3000 caused different reinforcing action in composite. Fourthly, the mechanical properties and the data of DMA indicated that the bond properties and dispersibility between fiber and rubber matrix were not good enough. It caused neither Sulfron3000 nor EE had been fully utilized in NR composite.It was worth to carry on further investigation of suitable methods to pretreat PPTA in order to obtain a better performance tire.Fifthly, theoretical prediction about the effect on running performance of tyre was made on the data of DMA. The results showed that both of two type of aramid short fiber predispersion had its own strong point in improving the properties of tyre. In chief, both Sulfron 3000 & EE could be well-dispersed in rubber matrix with predispersion of this two products and will become ideal reinforcement material for NR composite because of high modulus and high strength of aramid short fibre. It is hard to tell which the better one for NR composite is. The improvement on some properties of tyre is always accompanied with the sacrifice of some others. So Choice between Sulfron 3000 & EE as reinforcing filling of NR composite will be made according to requirement of tyre in designing of rubber products.