According to the present invention, an aqueous dispersion containing a graft copolymer satisfying (a) to (e) shown below and water is provided, and it is an aqueous dispersion containing a graft copolymer which shows an excellent dispersibility even in a state of reducing a surfactant and which is excellent in an affinity with a binder resin, a pigment and the like:
(a) a graft rate is 1 to 150 % by mass,
(b) a weight average molecular weight measured by GPC is 500 to 400000,
(c) a molecular weight distribution (Mw/Mn) is 1.5 to 4,
(d) a main chain is a polymerization chain containing a monomer unit having a hydrophilic group and
(e) a side chain is a homopolymerization chain of a single kind or a copolymerization chain of two or more kinds selected from α-olefins having 3 to 28 carbon atoms or a copolymerization chain comprising an α-olefin unit having 3 to 28 carbon atoms and an ethylene unit which accounts for 50 % by mass or less, wherein a mesopentad ratio [mmmm] of the polymerization chain is 30 to 80 mole %.
根据本发明,提供了一种含有满足下图(a)至(e)的接枝共聚物和
水的
水性分散体,它是一种含有接枝共聚物的
水性分散体,即使在减少表面活性剂的状态下也显示出优异的分散性,并且与粘合剂
树脂、
颜料等的亲和性优异:
(a) 接枝率为 1-150%(质量百分比)、
(b) 用
GPC 测得的平均分子量为 500 至 400000、
(c) 分子量分布(Mw/Mn)为 1.5 至 4、
(d) 主链是含有亲
水基团单体单元的聚合链,以及
(e) 侧链是单一种类的均聚链,或两种或两种以上的共聚链,选自具有 3 至 28 个碳原子的 α-烯烃,或由具有 3 至 28 个碳原子的 α-烯烃单元和
乙烯单元组成的共聚链,
乙烯单元的质量占 50%或更少,其中聚合链的中五元比[mmm]为 30 至 80 摩尔%。