TABLE OF CONTENTS Asphalt is a low-cost thermoplastic material, which is highly temperature-dependent. The addition of a thermoplastic rubber at 1 5% by weight greatly reduces the dependence of viscosity on temperature. Useful operating temperature ranges can often be doubled in this manner. The addition of a thermoplastic rubber, such as butyl rubber or polyisobutylene, at 10 30% by weight produces a truly thermoplastic product with elasticity, resilience, and high cohesive strength. Such mixtures are useful as sealants. Asphalt emulsions are used to increase solid content, improve water resistance, and lower the cost of laminating adhesives. Such adhesives are used in laminating paper and other packing materials where a water-barrier layer is required. Another important application is in roofing and flooring adhesives. [1 ,17 ,18 ]
