申请人:Kuraray Co., Ltd.
公开号:EP1440997A1
公开(公告)日:2004-07-28
An acrylic polymer powder obtained by coagulating and drying a latex containing acrylic polymer particles, in which acrylic polymer powder, the average particle size of the powder is 5 to 100µm, the percentage of void is 70 % or less, and the integral void volume on voids having a pore diameter of 1 µm or more is 0.9 mL/g or less. The acrylic sol obtained using the powder is excellent in storage stability and fluidity.
The storage stability and fluidity of the acrylic sol can further be heightened, or it is possible to give different effects (enhancement of mixing properties of the powder with a plasticizer; lowering of the viscosity of the acrylic sol, enhancement of particle destruction resistance; enhancement of the bleed-out resistance, film uniformity and flexibility of moldings obtained from the acrylic sol, formation of smooth film; etc.), by adjusting the macropore diameter and micropore diameter of the acrylic polymer powder, the ratio between the pore volume of macropores to the pore volume of micropores per gram of the powder or the particle size ratio between the length and breadth of the powder in a specific range; incorporating a water soluble macromolecule in the latex; making a reactive surfactant a constituent of the acrylic polymer particles; or using as the latex a mixed latex of two kinds of latexes containing mutually different acrylic polymer particles.
Further, the molding of the invention never generates hydrogen chloride gas when incinerated, which is different from moldings formed from polyvinyl chloride sol.
一种丙烯酸聚合物粉末,通过凝结和干燥含有丙烯酸聚合物颗粒的胶乳而获得,在这种丙烯酸聚合物粉末中,粉末的平均粒径为 5 至 100µm,空隙百分比为 70 % 或以下,孔径为 1 µm 或以上的空隙的整体空隙体积为 0.9 mL/g 或以下。使用该粉末获得的丙烯酸溶胶具有出色的储存稳定性和流动性。
丙烯酸溶胶的储存稳定性和流动性还可以进一步提高,或者通过调整大孔孔径来达到不同的效果(提高粉末与增塑剂的混合性;降低丙烯酸溶胶的粘度,提高颗粒的抗破坏性;提高丙烯酸溶胶的抗渗出性、薄膜的均匀性和模塑件的柔韧性,形成光滑的薄膜等)。此外,本发明的模塑方法还包括:通过调整丙烯酸聚合物粉末的大孔直径和微孔直径、每克粉末的大孔孔径与微孔孔径之比或粉末的长宽粒径比在特定范围内;在胶乳中加入水溶性大分子;将活性表面活性剂作为丙烯酸聚合物颗粒的成分;或使用含有相互不同的丙烯酸聚合物颗粒的两种胶乳的混合胶乳作为胶乳。
此外,本发明的模塑在焚烧时不会产生氯化氢气体,这与聚氯乙烯溶胶形成的模塑不同。