Study On Structure And Properties Of Domestic New Rubber SIBR And Its Application In Tire

The microcosmic structure of SIBR 2505 and 2535 were studied by means of Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Spectrometer (FTIR), Gel Permeation Chromatography (GPC), Differential Scanning Calorimeter (DSC), and Thermal Gravimetric Analysis (TGA). Compared with IR and SBR, the influence of Carbon Black varieties and content on the properties of the SIBR was investigated by physic mechanical properties and dynamic mechanical analysis. On basis of this, the application of SIBR in the tread rubber was investigated.The results showed that the styrene content of both SIBR were in the range of 21~23, the content of 3, 4-PI structure and 1, 2-PB structure of SIBR2505 were lower than SIBR2535. The glass transition temperature (Tg) of SIBR2505 was -37.9℃, and that of SIBR2535 was -28.7℃. Molecular weight distribution of SIBR2505 presented double-peak distribution,and there was a peak over the shoulder of high molecular weight side. Molecule configuration of SIBR2505 was very close, while that of SIBR2535 was very nearly spherical in shape, and the two kinds of SIBR possessedgood thermal stability characteristics. Because the chain regularity was not so good in SIBR, the unfilled SIBR had poor properties. The comprehensive performance of carbon black filled SIBR was superior to IR. At low frequency(RPA frequency scanning)or in the mixed processing, the energy consumption of SIBR was significantly lower than SBR, but the carbon black dispersion was worse than SBR; at high frequency, for example, extrusion process, the energy consumption and elastic effects was higher than SBR1712, but lower than SBR1502.The result of RPA strain scanning was that the Payne effect of SIBR2535 was more clear than SIBR2505.Under the same condition, the curing rate of SIBR was faster than SBR, and SIBR and SBR were the similar mechanical properties, but abrasion resistance of the former was slightly worse than SBR, and heat build-up and permanent deformation were lower than SBR, that showed compression heat resistance of SIBR preceded SBR. The abrasion resistance of SIBR was slightly lower than SBR. SIBR had excellent dynamic mechanical properties, high wet traction and lower rolling resistance. So SIBR could meet the requirements of high performance tire.The filling properties of SIBR was studied, the results showed that, the effects of carbon black specific surface area and carbon black content on the properties of SIBR were similar. With Increasing specific surface area or content of carbon black, the tensile strength, modulus at 300% and tear strength will be improved while the dynamic mechanical properties will be weakened. The carbon black filling properties of SIBR2505 and SIBR2535 are similar. The general properties of these two kinds of SIBR cured were the best when the amount of N330 was 50 phr. The dynamic mechanical properties of these two SIBR were excellent, but the rolling resistance of SIBR2505 was lower than that of SIBR2535 while the wet traction of SIBR2535 was better than that of SIBR2505. When carbon black and silica were used together, the change of mechanical properties of SIBR was not obvious with the increase of silica and decrease of carbon black.The comprehensive properties of SIBR in tread rubber was better than SBR; With the increase of the carbon black specific surface area, tc10 became longer, but tc90 became shorter, so the cure rate increased. For the carbon black with the same specific surface area, tc90 of the rubber filled with the higher structure one was shorter. N234 was more suitable for SIBR. The carbon black filling properties of SIBR2505 and SIBR2535 were similar in tire tread rubber, the mechanical properties and abrasion resistance of SIBR filled with carbon black N330 was the best. The comprehensive properties were the best when the amount of filler was 70phr. In the tire tread formula all used SIBR, the abrasion resistance of SIBR showed the best performance with 30 phr silica in silica/carbon black system content. In this formula, the compression heat resistance could not be improved by the using of silica.In SIBR/SBR/BR tire tread rubber formula, both the abrasion resistance and compression heat resistance were improved by the use of silica and this effect was clearer to SIBR2535. The dynamic mechanical properties of the two types SIBR were greatly improved, with the increase of white carbon black content , wet traction was improved while lower rolling resistance was reduced. When the comprehensive properties were considered, the suitable silica was 40 phr.