Novel vulcanizable silane-terminated polyurethane polymers

• US 4,645,816 A
• Filed: 06/28/1985
• Issued: 02/24/1987
• Est. Priority Date: 06/28/1985
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: Union Carbide Corporation (Dow, Inc.)
• Inventors: Pohl, Eric R., Osterholtz, Frederick D.
• Primary Examiner(s): WELSH JR, MAURICE
• Application Number:
  US06/749,785
• Time in Patent Office: 606 Days
• Field of Search: 528/28, 528/906
• US Class Current: 528/28
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/289 containing silicon
• CPC Class Codes: C08G 18/3893 containing silicon
• CPC Class Codes: C09K 3/1021 Polyurethanes or derivatives thereof
• CPC Class Codes: Y10S 528/906 Fiber or elastomer prepared from an isocyanate reactant

Abstract

Room-temperature curable isocyanate terminated polyurethane polymers whose terminal isocyanate groups have been reacted with a silane monomer having at least one dialkoxy silane group and an organo-functional group with at least one active hydrogen. The polymers crosslink to produce elastomeric polymers with improved elongation and flexibility.

Claims

1. A process for producing vulcanizable, dihydrocarbyloxysilyl-terminated polyurethane polymers having terminal end-blocking units of the formula:

##STR7## wherein R is C₁ -C₁₆ alkyl or C₆ -C₁₂ aryl;

R¹ is C₁ -C₄ alkyl;

R₂ is C₂ -C₁₈ alkylene or C₆ -C₁₈ arylene; and

Z is --O--, --S-- or --NR³, wherein R³ is hydrogen, ##STR8## or C₁ -C₁₆ alkyl, aminoalkyl or diaminoalkyl, with the proviso that when Z is --O--, R² must be C₄ -C₁₈ alkylene or C₆ -C₁₈ arylene, which comprises reacting;

(a) the --NCO terminal groups of an isocyanate-terminated polyurethane prepolymer with

(b) at least a stoichiometric amount of silane monomer of the formula;

##STR9## wherein R, R¹, R² and Z are as defined above.

2. A process as recited in claim 1 wherein

R is C₁ -C₁₆ alkyl;

R² is C₂ -C₈ alkylene; and

Z is --S-- or NH.

3. A process as recited in claim 2 wherein

R and R¹ are methyl or ethyl:

R2 is ethylene or propylene; and

Z is NH.

4. A process as recited in claim 3 wherein the silane is gammaaminopropyldimethoxymethylsilane.

5. A process as recited in claim 1 wherein the polyurethane prepolymer is the reaction product of polyoxyalkylene diol and an aromatic diisocyanate.

6. The process as recited in claim 5 wherein the polyoxyalkylene diol is polyoxyalkylene glycol and the aromatic diisocyanate is toluene diisocyanate.

7. The process as recited in claim 6 wherein the polyoxyalkylene glycol is polypropylene glycol.

8. The process as recited in claim 1 further comprising admixing with said polyurethane prepolymer and said silane monomer a silanol condensation catalyst in an amount sufficient to cure the polymer upon exposure to moisture.

9. The process as recited in claim 1 further comprising admixing a filler with said polyurethane prepolymer and said silane monomer.