Thermoplastic urethane elastomeric alloys

• US 5,516,857 A
• Filed: 06/07/1995
• Issued: 05/14/1996
• Est. Priority Date: 06/25/1993
• Status: Expired due to Fees

• Current Assignee: Refac International Limited
• Original Assignee: Refac International Limited
• Inventors: Mann, William H.
• Primary Examiner(s): Hamilton, III, Thomas
• Application Number:
  US08/474,095
• Time in Patent Office: 342 Days
• Field of Search: 525/457, 525/458, 525/129, 525/130, 525/424, 525/440
• US Class Current: 525/458
• CPC Class Codes: C08K 5/0016 Plasticisers
• CPC Class Codes: C08K 5/10 Esters; Ether-esters
• CPC Class Codes: C08L 2203/02 for biomedical use
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 75/04 Polyurethanes

Abstract

Thermoplastic urethane elastomeric alloys are obtained by melt compounding at least one first component that is a polyurethane elastomer having at least one plasticizer reacted therein, this first component being formed by heating a reaction mixture comprising at least one isocyanate having a functionality of less than about 2.2, at least one long chain polyol, at least one chain extender and at least one plasticizer in specified amounts at a temperature of at least about 330° F. (165.6° C.), with at least one second component that is another thermoplastic elastomer not within the definition of the first component.

Claims

1. A composition containing:

(a) from 5-95 wt. % of a first component of at least one first thermoplastic hot melt composition formed by heating to a temperature of at least about 330°

F. (165.6°

C.) a reaction mixture comprising at least one isocyanate having a functionality less than about 2.2, at least one chain polyol, at least one chain extender and at least one plasticizer, the NCO/QH ratio in the reaction system being about 0.95 to about 1.05, wherein said ingredients are present in amounts sufficient to meet the following formula;

##EQU2## wherein A represents the equivalent weight of the long chain polyol x the moles thereof used;

B represents the equivalent weight of the chain extender x the moles thereof used;

C represents the equivalent weight of the isocyanate used; and

D represents the grams of plasticizer, and

(b) from 95-5 wt. % of a second component of a polyurethane not within the definition of the first component.

2. A composition according to claim 1 wherein the isocyanate in the first component is MDI, HMDI or an isocyanate of the formula O═

C═

N--(D)--N═

C═

O where D is an aliphatic group of from 6 to 36 carbon atoms.

3. A composition according to claim 1 wherein the long chain polyol in the first component is a polyester polyol, a polycaprolactone polyol, a polyether polyol, or a polycarbonate polyol.

4. A composition according to claim 1 wherein the chain extender of the first component is a short chain diol of from 2 to about 10 carbon atoms.

5. A composition according to claim 4 wherein the chain extender of the first component is ethylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2-methyl-1,4-butanediol, 1,6-hexanediol, and 1,10-decanediol.

6. A composition according to claim 1 wherein the plasticizer is capable of being reacted into the polyurethane at a temperature of about 330°

F. (165.6°

C.).

7. A composition according to claim 6 wherein the plasticizer is butyl benzyl phthalate, dibutyl phthalate, dioctyl phthalate, or dipropylene glycol dibenzoate.

8. A composition according to claim 1 wherein the first component is present in an amount of from about 15 to about 85 wt. % and the second component is present in an amount of from about 85 to about 15 wt. %, the isocyanate in the first component is MDI, HMDI or an isocyanate of the formula O═

C═

N--(D)--N═

C═

O where D is an aliphatic group of from 6 to 36 carbon atoms, the long chain polyol in the first component is a polyester polyol, a polcaprolactone polyol, a polyether polyol, or a polycarbonate polyol, the chain extender is a short chain diol of from 2 to about 10 carbon atoms, and the plasticizer is capable of being reacted into the polyurethane at a temperature of about 330°

F. (165.6°

C.).

9. A composition according to claim 1 wherein the first component is present in an amount of from about 20 to about 80 wt. % and the second component is present in an amount of from 80 to about 20 wt. %.

10. A composition according to claim 1 wherein the first component is present in an amount of about 30 to about 70 wt. % and the second component is present in an amount of from about 70 to about 30 wt. %.

11. A method of preparing a composition of claim 1 comprising melt compounding at least one first component according to claim 1 with at least one second component according to claim 1 at a temperature of at least about 330°

F. (165.6°

C.).

12. A composition according to claim 1 wherein the composition has a compression set performance of between 15 and 20, as by ASTM D395-61.