Impregnated porous granules with slow-release pore membranes, and process for the manufacture thereof
申请人:STAUFFER CHEMICAL COMPANY
公开号:EP0005302A2
公开(公告)日:1979-11-14
Open-ended pores of a porous granule are filled with a liquid material which is at least partially immiscible with water, and sealed with a porous polyurea membrane which limits the release rate of the material into the surrounding medium. The membrane is formed by
(a) applying to the bare granule an organic solution comprising the liquid material and an organic polyisocyanate, followed by
(b) applying to the granule an aqueous solution comprising water and a catalytic amount of a catalyst selected from the group consisting of a basic organic tertiary amine and an alkyl tin carboxylate.
在多孔颗粒的开口孔中填充至少部分与水不相溶的液态材料,并用多孔聚脲膜密封,以限制材料释放到周围介质中的速度。聚脲膜的形成过程如下
(a) 在裸颗粒上涂抹由液态材料和有机多异氰酸酯组成的有机溶液,然后
(b) 对颗粒施加水溶液,该水溶液由水和一定量的催化剂组成,催化剂选自碱性有机叔胺和烷基羧酸锡。