Polyurethane elastomer and foam exhibiting improved abrasion resistance
AssigneeDow Italia s.r.l.
InventorStefano Mussini
Life of this patent
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Abstract
Disclosed is a polyurethane elastomer having a density of from about 100 to about 1100 kg/m.sup.3, and an abrasion loss of less than about 300 mg, as determined in accordance with Test Method A of ISO 4649. Such elastomer can be prepared by reacting a urethane-modified polyisocyanate with at least one polyol in the presence of from about 0.1 to about 10 parts per 100 parts by weight of polyol' of a liquid polybutadiene comprising 1,2-butene, 2,3-(trans)butene and 2,3-(cis)butene moieties, wherein the 1,2-butene content is less than about 50 percent, based on total butene content, and the 2,3 (cis)-butene content is greater than the 2,3-(trans)butene content.
Claims20
A polyurethane elastomer prepared by reacting:
- (a) a urethane-modified polyisocyanate, with
- (b) at least one polyether polyol or polyester polyol, in the presence of
- (c) from about 0.1 to about 10 parts per 100 parts by weight of (b) of a liquid polybutadiene comprising 1,2-butene, 2,3-(trans)butene and 2,3-(cis)butene moieties wherein the 1,2-butene content of less than about 50 percent, based on total butene content and the 2,3 (cis)-butene content is greater than the 2,3-(trans)butene content, with
- said elastomer being characterized in having (i) a density of from about 100 to about 1100 kg/m.sup.3, and (ii) an abrasion loss of less than about 300 mg, as determined in accordance with Test Method A of ISO 4649.
A polyurethane elastomer prepared by reacting:
- (a) a urethane-modified polyisocyanate which has an isocyanate content of from about 15 to about 30 weight percent and obtained by reacting a methylene diphenylisocyanate with a polyol, with
- (b) at least one polyester or polyether polyol, which is a diol or triol having an average hydroxyl equivalent weight of from about 500 to about 5000, in the presence of
- (c) from about 0.1 to about 10 parts per 100 parts by weight of (b) of a liquid polybutadiene comprising 1,2-butene, 2,3-(trans)butene and 2,3-(cis)butene moieties and having a molecular weight of from about 1000 to about 10000 wherein the a 1,2-butene content is less than about 35 percent, and the 2,3 (cis)-butene content is at least 60 percent, both percentages based on total butene content.
- said elastomer being characterized in having (i) a density of from about 100 to about 1100 kg/m.sup.3, and (ii) an abrasion loss of less than about 300 mg, as determined in accordance with Test Method A of ISO 4649.
A method for improving the abrasion resistance of a polyurethane elastomer which comprises reacting a urethane-modified polyisocyanate with at least one polyether polyol or polyester polyol in the presence of a liquid polybutadiene, wherein:
- (a) the polybutadiene is present in an amount of from about 0.1 to about 10 parts per 100 parts by weight of polyol, and comprises 1,2-butene, 2,3-(trans)butene and 2,3-(cis)butene moieties the 1,2-butene content being less than about 50 percent based on total butene content and the 2,3 (cis)-butene content is greater than the 2,3-(trans)butene content;
- and
- (b) the polyisocyanate is present in an amount sufficient to provide an isocyanate reaction index of from about 80 to about 120.
Dependencies are inferred from the claim text.