Process for producing polyurethane elastomers
AssigneeTakeda Chemical Industries, Ltd.
InventorsYasuyuki Kajita, Tsutomu Kubota, Kenji Kudo
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Abstract
A method for producing a polyurethane elastomer which comprises reacting (1) either a polyisocyanate and a polyol or an isocyanate-terminated prepolymer obtainable by reacting said polyisocyanate with said polyol with (2) a diol of general formula ##STR1## wherein A.sub.1 and A.sub.2 are the same or different and each represents a bond, --O-- or --COO--; R.sub.1 and R.sub.2 are the same or different and each represents C.sub.1-6 alkylene; X.sub.1 and X.sub.2 are the same or different and each represents H or hydroxyalkyl and (3) a triol having a hydroxyl equivalent of 60 to 500, gives a polyurethane elastomer with improved tensile strength, tear strength and other mechanical properties.
Claims1
A polyurethane elastomer curing composition which consists of a diol of the general formula ##STR4## wherein A.sub.1 and A.sub.2 are the same or different and each represents a bond, --O-- or --COO--;
- R.sub.1 and R.sub.2 are the same or different and each represents C.sub.1-6 alkylene;
- and X.sub.1 and X.sub.2 are the same or different and each represents H or hydroxylalkyl, and
- a triol having a hydroxyl equivalent weight of 60 to 500 and being selected from the group consisting of (a) a trifunctional polyether polyol obtained by random or block addition reaction between at least one of trimethylolpropane or glycerol and at least one alkylene oxide, (b) a trifunctional polyester polyol obtained by addition reaction between at least one of trimethylolpropane or glycerol and at least one cyclic ester and (c) a hydroxyl-containing fatty acid ester which is the product of condensation between at least one of trimethylolpropane and glycerol and at least one hydroxyl-containing fatty acid, the weight ratio of the diol and the triol being 1:0.05 to 1.5.
Dependencies are inferred from the claim text.