摘要 |
A high impact resistant macromolecular network is disclosed that includes a basic, stiff framework interconnected by soft, shock-absorbing multiple bridges to cushion thermoelastic stresses. The network is prepared by polymerizing or copolymerizing with vigorous agitation, an unsaturated hard material (characterized in that when homopolymerized, it forms a polymeric material that is below its glass transition temperature at ambient temperature), in the presence of a soft moiety selected from the group consisting of vinyl substituted siloxane, allyl substituted siloxane, acrylate terminated or substituted siloxane, and unsaturated hydrocarbon polymer, to form a partially polymerized mixture in which the soft moiety is homogeneously distributed; pouring the partially polymerized mixture into a mold, and then completing the polymerization without agitation. The final products are dimensionally exact and stable, transparent, easily machinable and resilient, and can be designed to have good optical properties.
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