Method for producing millable polyurethanes and polyurethane elastomers
First Claim
1. A method for producing a crosslinkable millable polyurethane rubber having substantially no hard segments and being millable on conventional rubber machinery comprising the steps of:
- producing a poly-ε
-caprolactone based diol represented by formula (I) ##STR3## wherein ( ) is a caprolactone unit;
m and n are numbers of caprolactone units; and
R1 is a divalent group derived from a polymerization initiator of formula R1,(OH)2, the poly-ε
-caprolactone based diol containing a controlled average number of caprolactone units and having a molecular weight distribution Mw/Mn of 1.0 to 1.5; and
reacting said poly-ε
-caprolactone based diol with a diisocyanate to produce a polyurethane rubber having a restricted crystallizability.
3 Assignments
0 Petitions
Accused Products
Abstract
A method for producing millable polyurethanes by first producing a poly-ε-caprolactone based diol, the poly-ε-caprolactone based diol containing a controlled average number of caprolactone units and having a molecular weight distribution; and reacting the poly-ε-caprolactone based diol with a diisocyanate to produce a polyurethane with a restricted crystallizability having a rubber elasticity. The resulting millable polyurethanes exhibit excellent hydrolysis resistance, show no crystallization at low temperatures and have excellent mechanical properties.
-
Citations
13 Claims
-
1. A method for producing a crosslinkable millable polyurethane rubber having substantially no hard segments and being millable on conventional rubber machinery comprising the steps of:
-
producing a poly-ε
-caprolactone based diol represented by formula (I) ##STR3## wherein ( ) is a caprolactone unit;
m and n are numbers of caprolactone units; and
R1 is a divalent group derived from a polymerization initiator of formula R1,(OH)2, the poly-ε
-caprolactone based diol containing a controlled average number of caprolactone units and having a molecular weight distribution Mw/Mn of 1.0 to 1.5; andreacting said poly-ε
-caprolactone based diol with a diisocyanate to produce a polyurethane rubber having a restricted crystallizability. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
Specification