Faculteit Engineering Technology
Afdeling Elastomer Technology and Engineering (MS3)
Master opleiding Mechanical Engineering
In het kader van zijn/haar doctoraalopdracht zal
Bisschop, R. (Rick)
een voordracht houden getiteld:
Processing of Modern Passenger Car Tire Treads
In the future, the CO2 emission of passenger cars should in fact be reduced. As a consequence, the rolling resistance of the tire tread has to be improved since it has a significant impact on the fuel consumption of the car. Therefore, four typical passenger car tire tread rubbers are analysed namely two butadiene rubbers (BR) and two functionalized styrene-butadiene rubbers (SBR). One of these BRs is functionalized and the main difference between both SBRs is the chemical composition of the polymer which results in a different glass-transition temperature (Tg). To understand the behaviour of the individual rubber, the four polymers are blended together in various blend ratios. The reinforcing filler content is constant in each blend, however, two types of silica with different surface areas are used. Hence, the influence of functionalization and chemical composition of polymers on the processing behaviour and dynamic mechanical properties is investigated in this research.
It shows that the chemical composition of the functionalized butadiene rubber in the SBR/BR blends improve the micro and macro filler dispersion in the compounds. This leads to better dynamic and mechanical properties of the tread compound independently of the specific surface area of the used type of silica. Hence, the reinforcement index is increased and the loss factor tangent delta (tan δ) at 60°C is reduced while the tan δ at 0°C is similar to the non-functionalized BR. Therefore, the rolling resistance is improved without negatively influencing the dry and wet grip properties.
Besides, the two functionalized styrene-butadiene rubbers are blended together and clearly show a difference in both micro and macro filler dispersion due to their chemical compositions. However, the dynamic and mechanical properties partially depend on the type of silica that is used. For both fillers, it applies that tan δ at low temperatures is strongly influenced by the chain flexibility or Tg of the blends. Hence, the wet and dry grip deteriorates with decreasing Tg. However, the tan δ at 60°C is partially influenced by the type of silica and the Tg of the compounds.
|Prof. dr. A. Blume
Dr. F. Grunert
Dr. M.I. Abdul Rasheed
Dr. S. Ilisch