Abstract: The present invention relates to an energy absorbent medium which is compliant and conformable in the absence of an applied force, and stiffens in response to the rate of an applied force to dissipate energy. The medium comprises a blend of a polymer and a lubricant incompatible with the polymer to produce a conformable absorbent which exhibits dilatant (shear thickening) characteristics under high rates of force or stress. The polymer has reformable sacrificial chemical bonds which are broken under a high rate of deformation and which reform under static conditions. Suitable polymers for the invention include polyborosiloxanes. Applications for the medium include absorbent for sports padding, athletic equipment, motor vehicle seats, bulletproof vests, medical equipment, industrial equipment, weaponry, and playing fields.

Abstract: A tackifier resin is prepared by polymerizing a monomer mixture of 10-70% piperylene concentrate and 30-90% of a vinyl aromatic monomer in the presence of a boron trifluoride catalyst and an inert diluent. The resin is water white in color, has a Gardner number of less than one, a softening point of 60.degree. to 120.degree. C. and a polydispersity of 1 to 5. The tackifier is used in formulations based on EVA, block copolymers and polyolefins for hot melt and pressure sensitive adhesive applications.