Effect of Adhesive on the Impact Resistance of Laminated Plastics for Windshield Applications.

摘要

Clamped acrylic-polycarbonate laminates show improved resistance to penetration over that shown by either material alone. Use of thermal bonding techniques or brittle adhesives to form a laminate result in a significant decrease in the ballistic resistance. The brittle adhesive induces spallation of the polycarbonate causing a significantly lower impact resistance and changes the mode of failure from ductile to brittle. Flexible transparent polyurethane adhesives were synthesized with systematic variation in proportions of monomer and structure of the soft segments. Ballistic resistance of laminates using these adhesives was improved by forty percent. The change in relative amount of the hard segment had no significant effect upon the impact behavior. Strength of adhesive bonding was varied by a factor of two through changes in laminating temperature. No correlation between bond strength and ballistic performance was found. Thus,laminates using transparent flexible adhesives with sufficient bond strength to prevent delamination upon impact show ballastic resistance up to fifty percent better than the best commercially available transparent impact resistant polymeric material. (Author)