Moisture curable polymers having terminal or pendant silyl groups of the formula:
where R1 represents an alkyl group having 1 to 10 carbon atoms, optionally interupted with one or more ether oxygen atoms, or a group of the formula
R2 represents a C1 to C6 alkoxy group or a C6-C8 aryloxy group;
R3 represents an alkyl or an aryl group;
T represents a branched or cyclic alkylene radical of 4 to 10 carbons, which may be optionally interrupted by one or more ether oxygen atoms;
X is an alkylene group of 3-10 carbon atoms, which may be linear, branched or cyclic;
and a is 0, 1 or 2, may be prepared by reacting (A) a compound having at least two isocyanate groups thereon with (B) a silane of formula (3):
Moisture cured sealant formulations formulated with the polymers exhibit improved thermal stability, elongation, and tear resistance.
具有末端或侧链
硅基基团的湿度固化聚合物,其
化学式为:其中R1代表具有1至10个碳原子的烷基,可选地中断一个或多个醚氧原子,或者是
化学式R2代表C1至C6烷氧基或C6-C8芳氧基的基团;R3代表烷基或芳基基团;T代表4至10个碳原子的分支或环状烷基基团,可选地中断一个或多个醚氧原子;X是3-10个碳原子的烷基基团,可线性、分支或环状;a为0、1或2。可以通过将(A)至少具有两个
异氰酸酯基团的化合物与(B)
化学式(3)的
硅烷反应来制备这些聚合物。使用这些聚合物制备的湿度固化密封剂配方表现出改善的热稳定性、延展性和撕裂强度。