New modified silica for optimized tire tread development
In addition to high performance targets for tires, modern car tread development places increasing value on problem-free and resource-saving processing. In the course of the introduction of silica mixtures and their optimization over the past 25 years, the processability of the increasingly filled mixtures became more difficult and more energy intensive. The next step in improving both tire performance and compound processing is the fundamental chemical redesign of the raw materials rubber and filler. This article shows ways to significantly improve both the technical performance and the processing of tread compounds and to reduce resource consumption by using optimized surface-modified silica.
Modern car tread development places increasing value on problem-free and resource- saving processing as well as in high performance targets for tires. In the course of the introduction of silica mixtures and their optimization over the past 25 years, the processability of the increasingly filled mixtures became more difficult and more energy intensive. Silicic acid as a polar filler cannot be easily distributed in the non-polar matrix of the usual BR/SSBR blends in the high dosages of car tread mixtures from 70 phr to 120 phr. First, processing was improved with process additives, with liquid elastomers, the rubbers used and also HD silicas. However, the chemical nature of today’s raw materials and the processes used still lead to high energy losses in production. If one could save this energy, one could, for example, operate 300 LED energy-saving lamps of 15 W each for one hour. This amount of energy is generated four to five times an hour.
The next step in improving both tire performance and compound processability might be the fundamental chemical redesign of the raw materials rubber and filler. This article shows ways to improve both technical performance and processing of passenger car tread compounds by using optimized surface-modified silica and thereby massively reduce VOC’s and unnecessary energy losses in production. The new silica presented is a candidate for the resource-saving production of new compounds for future generations of electrically powered cars.
The surface-modified type enables a simple and short mixing process, short curing times and the lowest VOC development and guarantees energy-efficient and cost-effective mixture production. High static and complex moduli with high elongation at break and resistance to tearing can be achieved. The DIN abrasion is significantly higher than the comparison group and gives hope for corresponding results on the tire. The indicators for wet grip and rolling resistance are also advantageous for the new silica. The results, which are less favorable in terms of balance for snow and ice properties, can be corrected by simple, known compounding measures if necessary.
J. Bertrand, RFP Rubber Fibres Plastics, 04 2020, 186-190.