| 摘要 |
Polyurethane foams having improved retention of insulative properties can be prepared using one or more of two novel polyols. One of the polyols is a polyether having general formula (I), wherein T is any group substantially unreactive with epichlorohydrin except a halogen, Z is an integer from 0 to 8 and Q has general formula (II), wherein A is N, S or O; L is a covalent bond or a connecting group having from 1 to 10 carbons; I is an integer from 1 to 10; J is an integer from 2 to 8; and D is H, L-(((CH2CH2O)I)H)J, an alkyl or an aromatic group if A is N or an electron pair if A is S or O, prepared by reacting a monoepoxide with a compound having general formula (III), wherein X is H, Li, Na, K; A is N, S or O; L is a covalent bond or a connecting group having from 1 to 10 carbons; M is any group capable of reacting with an ethylene oxide molecule in the presence of a basic catalyst; and J is an integer from 2 to 8. The other polyol is prepared by (1) admixing ethylene carbonate and one or more hydroxyl functional compounds under reaction conditions sufficient to react the ethylene carbonate and the hydroxyl functional compounds to produce a polyol precursor, and (2) admixing the polyol precursor with diethylene glycol and an anhydride, a dicarboxylic acid, a tricarboxylic acid or mixtures thereof, optionally in the presence of a catalyst. |
