Energy absorbing laminated glass, pref. for use as automobile windscreens, consists of a glass sheet bonded to a sheet of a urethane derived from (I) a linear aliphatic polycarbonate possessing -OC(=O)O- bonds and 2 gps. reactive with isocyanate gps the polycarbonate having a mol.wt. 500-5000, (II) a diisocyanate, and (III) a cpd. with a mol.wt. 250 contg. =2 active H atoms, which react with isocyanate gps. Pref. the urethane is placed between two glass sheets. The polycarbonate possesses ether linkages ina ratio (relative to ether-to-carbonate linkages) of 2-10:1 pref. 3-6:1. (I) is a cycloaliphatic diisocyanate, pref, 4,4'-methylene-bis-(cyclohexylisocyanate). (III) is an aliphatic diol, pref. 1,4-butanediol. The urethane bonds firmly to the glass giving high impact resistance over a wide temp. range, good resistance to shearing and tearing and a high optical transparency.
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