Polyether polyol, method for producing polyether polyol, polyester elastomer and polyurethane
The present invention provides a high-molecular-weight polyether polyol ensuring that when used as a polyurethane raw material, a polyurethane having excellent flexibility and elastic recovery can be obtained; and a method for producing, with high productivity, a polyether polyol having a higher number average molecular weight and a narrower molecular weight distribution than those of the raw material polyether polyol, and the polyether polyol of the present invention has a number average molecular weight of 3,500 to 5,500 and a molecular weight distribution of 1.7 to 3.0.
1. A polyether polyol, which is a polytetramethylene ether glycol, wherein:
repeating units in a main framework of the polytetramethylene ether glycol consist of only 1,4-butanediol units;
the polytetramethylene ether glycol has a number average molecular weight of 3,500 to 5,500;
the polytetramethylene ether glycol has a molecular weight distribution of 1.8 to 2.2; and
a viscosity of the polytetramethylene ether glycol is 5,500 mPa·s or less, as measured at 40° C. by means of an E-type rotary viscometer.
2. A polyester elastomer, comprising, as constituent units:
the polyether polyol according to claim 1 ;
a diol (excluding the polyether polyol); and
a dicarboxylic acid.
3. A method for producing a polyether polyol, which is a polytetramethylene ether glycol, the method comprising:
subjecting a mixed solution comprising a raw material polytetramethylene ether glycol having a number average molecular weight of 2,500 or more, water and an alcohol to a layer separation, to obtain a product polytetramethylene ether glycol,
wherein:
repeating units in a main framework of the product polytetramethylene ether glycol consist of only 1,4-butanediol units;
the product polytetramethylene ether glycol has a number average molecular weight of 3,500 to 5,500, which is 300 or more higher than a number average molecular weight of the raw material polytetramethylene ether glycol;
the product polytetraymethylene ether glycol has a molecular weight distribution of 1.8 to 2.2; and
a viscosity of the product polytetramethylene ether glycol is 5,500 mP·s or less, as measured at 40° C. by means of an E-type rotary viscometer.
4. The method for producing a polyether polyol according to claim 3 , wherein:
a molecular weight distribution of the raw material polytetraymethylene ether glycol is 2.0 or more; and
a molecular weight distribution of the product polytetraymethylene ether glycol is 0.2 or more lower than the molecular weight distribution of the raw material polytetraymethylene ether glycol.
5. The method for producing a polyether polyol according to claim 3 , wherein a mixed solution temperature during the layer separation is 31° C. or more.
6. The method for producing a polyether polyol according to claim 3 , wherein at least one member selected from the group consisting of an organic carboxylic acid, an organic sulfonic acid and an inorganic acid is added to the mixed solution before the layer separation.
7. The method for producing a polyether polyol according to claim 6 , wherein phosphoric acid or sulfuric acid is added as an inorganic acid to the mixed solution before the layer separation.
8. The method for producing a polyether polyol according to claim 3 , wherein the alcohol is an aliphatic alcohol having a carbon number of 1 to 10.
9. A polyurethane, comprising, as constituent units:
a polytetramethylene ether glycol having a number average molecular weight of 3,500 to 5,500, a molecular weight distribution of 1.8 to 2.2, and a viscosity of 5,500 mPa·s or less as measured at 40° C. by means of an E-type rotary viscometer; and
an isocyanate compound,
wherein repeating units in a main framework of the polytetramethylene ether glycol consist of only 1,4-butanediol units.
10. The polyurethane according to claim 9 , further comprising:
a chain extender (excluding the isocyanate compound).
11. A fiber, which uses the polyurethane according to claim 9 .
12. An artificial or synthetic leather, which uses the polyurethane according to claim 9 .
13. A coating agent, which uses the polyurethane according to claim 9 .
14. A polyether polyol, which is a polytetramethylene ether glycol, wherein:
repeating units in a main framework of the polytetramethylene ether glycol consist of only 1,4-butanediol units;
the polytetramethylene ether glycol has a number average molecular weight of 3,500 to 5,500;
the polytetramethylene ether glycol has a molecular weight distribution of 1.8 to 3.0; and
a viscosity of the polytetramethylene ether glycol is 5,500 mPa·s or less, as measured at 40° C. by means of an E-type rotary viscometer.
15. A method for producing a polyether polyol, which is a polytetramethylene ether glycol, the method comprising:
subjecting a mixed solution comprising a raw material polytetramethylene ether glycol having a number average molecular weight of 2,500 or more, water and an alcohol to a layer separation, to obtain a product polytetramethylene ether glycol,
wherein:
repeating units in a main framework of the product polytetramethylene ether glycol consist of only 1,4-butanediol units;
the product polytetramethylene ether glycol has a number average molecular weight of 3,500 to 5,500, which is 300 or more higher than a number average molecular weight of the raw material polytetramethylene ether glycol;
the product polytetraymethylene ether glycol has a molecular weight distribution of 1.8 to 3.0; and
a viscosity of the product polytetramethylene ether glycol is 5,500 mPa·s or less, as measured at 40° C. by means of an E-type rotary viscometer.
16. A polyurethane, comprising, as constituent units:
a polytetramethylene ether glycol having a number average molecular weight of 3,000 to 5,500, a molecular weight distribution of 1.8 to 3.0, and a viscosity of 5,500 mPa·s or less, as measured at 40° C. by means of an E-type rotary viscometer; and
an isocyanate compound,
wherein repeating units in a main framework of the polytetramethylene ether glycol consist of only 1,4-butanediol units.