Balancing wear and traction with lithium catalyzed polymers

Abstract

This paper is a report of methods of balancing wear and traction in passenger tire treads with lithium catalyzed polymers. The results demonstrate the versatility of the alkyllithium system for preparing a wide variety of polymers and copolymers with differing wear and traction properties in passenger tire treads. In addition, the use of this system for preparing polymers with improved processing and green strength is briefly discussed. ZUSAMMENFASSUNG :Es wird iiber den Ausgleich von VerschleiB und Rutschverhalten bei Personenwagenreifen mit Lithium-katalysierten Polymeren berichtet. Die Ergebnisse zeigen die Vielfaltigkeit von Alkyllithium-Systemen zur Herstellung einer breiten Palette von Polymeren und Copolymeren mit verschiedenen VerschleiB-und Abriebeigenschaften. Ferner wird die Anwendung dieses Systems fiir die Herstellung von Polymeren mit verbesserter Verarbeitbarkeit und Festigkeit diskutiert.In a previous paperl, we demonstrated the versatility of the alkyllithium system for preparing butadienelstyrene copolymers with a wide variety of propert,ies and applications. I n addition, we demonstrated a relationship between tread wear and traction properties in passenger tires constructed from butadiene/styrene copolymers with varying styrene content and varying microstructure. We showed that as the styrene content or vinyl content was increased in the polymers, a corresponding increase in T, (glass transition temperature) resulted. Also, the compounded stocks from these polymers exhibit,ed an increase in the YMI** with increasing vinyl or styrene content. The wear resistance properties of tires were shown t o decrease with increasing * Paper presented a t the meeting of the GDCh-Fachgruppe "Makromoleku-* * Temperature where YOUNG'S Modulus Index reaches 10000 lbs./sq.in. -ASTM lare Chemie" in Bad Nauheim, Germany, March 21, 1972. 797-64.