A polysiloxane prepolymer that is useful for forming biomedical devices comprises blocks (I) and (II) and is terminated at each end with an ethylenically unsaturated radical:
(*Dii*Diol*Dii*PS)
x
(I)
(*Dii*PS)
y
(II)
wherein: each Dii is independently a diradical residue of a diisocyanate; each Diol is independently a diradical residue of a diol having 1 to 10 carbon atoms; each PS is independently a diradical residue of a polysiloxane-containing diol or diamine; each * is independently —NH—CO—NH—, —NH—COO— or —OCO—NH—: x represents the number of blocks (I) and is at least 2, and y represents the number of blocks (II) and is at least 1.
一种可用于形成
生物医学设备的聚
硅氧烷预聚物由嵌段(I)和嵌段(II)组成,并在两端以
乙烯基不饱和基为端基:
(*Dii*Diol*Dii*PS)
x
(I)
(*Dii*PS)
y
(II)
其中:每个 Dii 独立地是二
异氰酸酯的二元残基;每个 Diol 独立地是具有 1 至 10 个碳原子的二元醇的二元残基;每个 PS 独立地是含聚
硅氧烷的二元醇或二元胺的二元残基;每个 * 独立地是-NH-CO-NH-、-NH-COO-或-OCO-NH-:x 代表嵌段(I)的数目且至少为 2,y 代表嵌段(II)的数目且至少为 1。