Incorporation of Low Viscosity Amorphous Propylene-Ethylene Copolymers in Adhesive and Sealant Formulations, 1998 Hot Melt Symposium Proceedings

Amorphous polyolefins (APO) are used extensively for paper, film and foil laminations, and as ingredients in hot melt adhesives and sealants. They are also used in rubber compounding, in waterproofing compounds for wire and cable applications and as a modifier for asphalt in single-ply roofing. In these applications, amorphous polyolefins are used to enhance adhesion and tack and to improve the flexibility of the formulation. Historically, amorphous polyolefins were produced as a by-product of isotactic polypropylene synthesis. However, advances in catalyst technology have eliminated this by-product from most polypropylene processes and direct synthesis APO’s were introduced to fill the market demand for amorphous polyolefins. With the capability to directly synthesize amorphous polyolefins, it is possible to tailor the polymer to provide specific properties required for various end uses. The polymer variables that are controlled include molecular weight and comonomer content. Using these variables, an amorphous propylene-ethylene copolymer specifically designed for use in low temperature adhesive and sealant applications has been developed. This paper will compare the performance of Eastoflex E1003 APO (An Amorphous Propylene-Ethylene Copolymer) in hot melt adhesive and sealant formulations versus other additives such as polyisobutylene used to improve low temperature performance.