| 摘要 |
PURPOSE:To obtain the subject lightweight and thin-wall granules useful for organic pigments, thermal insulating materials, etc., from a latex containing polymeric particles having specific laminated structure, using a base and acid, etc. CONSTITUTION:(I) 100 pts.wt. of a latex having polymeric particles with at least three-layered structure obtained from (A) a central layer polymer prepared by copolymerization between (1) 20-60 (pref. 30-50)wt.% of a carboxyl group- bearing monomer (e.g. acrylic acid) and (2) 80-40 (pref. 70-50)wt.% of a monomer copolymerizable with the component 1 (e.g. styrene, divinylbenzene) in the presence of seed particles prepared in advance, (B) an interlayer polymer prepared by copolymerization between (3) 1-12wt.% of a carboxyl group-bearing monomer and (4) 99-88wt.% of a monomer copolymerizable with the component 3 in the presence of the seed particles and (C) a surface layer polymer prepared by polymerizing a carboxyl group-free monomer in the presence of the components A and B are incorporated with (II) 2-10 pts.wt. of a base (e.g. sodium hydroxide) followed by 1-10 pts.wt. of an acid (e.g. hydrochloric acid, sulfuric acid), and the resultant system is put to after-treatment, thus obtaining the objective hollow polymeric granules. |
