'On the Reason that Passenger Tire Sidewals are Based on Blends of Natural Rubber and cis-Polybutadiene'

摘要

Sidewalls of passenger tires are commonly based on blends of equal proportions of natural rubber and cis-polybutadiene.These blends are known to be heterogeneous.Suitable compositions must be designed to withstand "extremes" of tire service.Not only must a sidewall have outstanding resistance to catastrophic crack growth under severe service conditions,e.g.,when a tire runs into a curb or hits a deep chuckhole,but also a sidewall must resist crack growth over long times at smaller strains experienced during "normal" rolling.Moreover,sidewalls must ressit both types of crack growth over a wide range of temperatures,and after aging for many years.