Novel vulcanizable silane-terminated polyurethane polymers

DETAILED DESCRIPTION What is claimed is: 1.
A process for producing vulcanizable, dihydrocarbyloxysilyl-terminated polyurethane polymers having terminal end-blocking units of the formula: ##STR7## wherein R is C.
sub.
1 -C.
sub.
16 alkyl or C.
sub.
6 -C.
sub.
12 aryl; R.
sup.
1 is C.
sub.
1 -C.
sub.
4 alkyl; R.
sub.
2 is C.
sub.
2 -C.
sub.
18 alkylene or C.
sub.
6 -C.
sub.
18 arylene; and Z is --O--, --S-- or --NR.
sup.
3, wherein R.
sup.
3 is hydrogen, ##STR8## or C.
sub.
1 -C.
sub.
16 alkyl, aminoalkyl or diaminoalkyl, with the proviso that when Z is --O--, R.
sup.
2 must be C.
sub.
4 -C.
sub.
18 alkylene or C.
sub.
6 -C.
sub.
18 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, R.
sup.
1, R.
sup.
2 and Z are as defined above.
2.
A process as recited in claim 1 wherein R is C.
sub.
1 -C.
sub.
16 alkyl; R.
sup.
2 is C.
sub.
2 -C.
sub.
8 alkylene; and Z is --S-- or NH.
3.
A process as recited in claim 2 wherein R and R.
sup.
1 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.




Description:
FIELD OF THE INVENTION This invention relates to a novel class of room temperature, moisture curable and silane-terminated polyurethane polymers with improved elongation, flexibility and low modulus