反相水性乳液法制备聚酰亚胺微球形貌调控及影响因素
|
摘要
利用聚酰胺酸三乙胺盐可溶于水的特性,利用反相乳液技术,以液体石蜡为连续相,含水的聚酰胺酸盐为分散相,非离子型表面活性剂Span 80/Span 85为乳化剂,通过化学酰亚胺法制备聚酰亚胺微球。重点研究聚酰亚胺分子链结构和HLB值对聚酰亚胺微球形貌的调控作用。研究结果表明,随着聚酰亚胺分子链结构刚性降低,分别得到半球、多孔球以及带凹陷的微球。针对均苯四甲酸酐(PMDA)/4,4′-二氨基二苯醚(ODA)体系,当乳化剂体系的HLB值从1.8增加到4.3时,微球形貌从微球逐渐转变成半球,球表面的凹陷逐渐减少。此外,还对比研究了酰亚胺方法和搅拌速率对微球形态的影响。研究表明热酰亚胺化只能得到粘结严重的纳米微球;搅拌速度过快或过慢都可能造成微球破裂或变形。
Polyimide microspheres were prepared by chemical imidization on the basis of the common inverse emulsion technique using properties of polyamic acid triethylamine salt dissolved in water.Inverse emulsion was fabricated with the mixed solution of poly(amic acid)ammonium salt and water as dispersed phase,liquid paraffin as continuous phase and Span 80/Span 85 as surfactant.This paper focused on controlling the morphology of polyimide(PI)microspheres through changing the molecular structures of PI and HLB value.Research results indicate that,according to decreasing the rigid of polyimide molecular chain,hemisphere,porous sphere and sphere with meteor crater can be got.For the PI spheres made with pyromellitic dianhydride/4,4′-oxydianiline(PMDA/ODA),with the HLBvalue of emulsifiers increasing from 1.8to 4.3,the morphology of microspheres changes from sphere to hemisphere with meteor crater reduced.In addition,the effects of the stirring speed and the imidization method on polyimide microspheres morphology were checked.Research results indicate that nano spheres can be obtained by thermal imidization with severe adhesion;too fast or too slow stirring can cause microspheres cracking or deformation.
Polyimide microspheres were prepared by chemical imidization on the basis of the common inverse emulsion technique using properties of polyamic acid triethylamine salt dissolved in water.Inverse emulsion was fabricated with the mixed solution of poly(amic acid)ammonium salt and water as dispersed phase,liquid paraffin as continuous phase and Span 80/Span 85 as surfactant.This paper focused on controlling the morphology of polyimide(PI)microspheres through changing the molecular structures of PI and HLB value.Research results indicate that,according to decreasing the rigid of polyimide molecular chain,hemisphere,porous sphere and sphere with meteor crater can be got.For the PI spheres made with pyromellitic dianhydride/4,4′-oxydianiline(PMDA/ODA),with the HLBvalue of emulsifiers increasing from 1.8to 4.3,the morphology of microspheres changes from sphere to hemisphere with meteor crater reduced.In addition,the effects of the stirring speed and the imidization method on polyimide microspheres morphology were checked.Research results indicate that nano spheres can be obtained by thermal imidization with severe adhesion;too fast or too slow stirring can cause microspheres cracking or deformation.
引文
[1]陈丽,倪孝威,陈莉莉,等.分散聚合法制备聚酰亚胺粒子及其形貌分析[J].高分子材料科学与工程,2009,25(5):36-38.Chen L,Ni X W,Chen L L,et al.Synthesis of polyimide microparticles and its analysis of morphology[J].Polymer Materials Science&Engineering,2009,25(5):36-38.
[2]蒋远媛,阙正波,王晓东,等.聚酰亚胺的微球化[J].高等学校化学学报,2008,29(10):2091-2095.Jiang Y Y,Que Z B,Wang X D,et al.Research on sphericization of polyimide[J].Chemical Journal of Chinese Universities,2008,29(10):2091-2095.
[3]Zhao G,Ishizaka T,Kasai H,et al.Fabrication of unique porous polyimide nanoparticles using a reprecipitation method[J].Chem.Mater.,2007,19:1901-1905.
[4]Frank H,Ziener U,Landfester K.Formation of polyimide nanoparticles in heterophase with an ionic liquid as continuous phase[J].Macromolecules,2009,42:7846-7853.
[5]Kasai H,Mitsui H,Zhao G,et al.Fabrication of porous nanoscale polyimide structures[J].Chem.Lett.,2008,37:1056-1057.
[6]Jing J,Ding S,Zhang C,et al.Fabrication of size-controllable hollow nano-spheres based on polyimides composites[J].Mater.Chem.Phys.,2009,116:330-334.
[7]卢建军,赵晓博,刘妙青.反相非水乳液法制备聚酰亚胺微球[J].高分子学报,2010(12):1479-1482.Lu J J,Zhao X B,Liu M Q.Preparation of polyimide microspheres in non-aqueous inverse emulsion[J].Acta Polymerica Sinica,2010(12):1479-1482.
[8]Yang Y,Jia Z,Wang Y,et al.Preparation of hemispherical polyimide particles by inverse emulsion technique from poly(amic acid)ammonium salts[J].Colloid Polym.Sci.,2013,291:1049-1055.
[9]Ma L,Yang Y,He C,et al.In situ preparation and characterization of polyimide/silica composite hemispheres by inverse aqueous emulsion technique and sol-gel method[J].Colloid Polym.Sci.,2015,293:1281-1287.
[10]尚小琴,童张法,龚福忠,等.含固相淀粉的反相乳液体系稳定性研究[J].高分子材料科学与工程,2007,23(3):70-73.Shang X Q,Tong Z F,Gong F Z,et al.The stability of inverse emulsion including starch granule[J].Polymer Materials Science&Engineering,2007,23(3):70-73.
[2]蒋远媛,阙正波,王晓东,等.聚酰亚胺的微球化[J].高等学校化学学报,2008,29(10):2091-2095.Jiang Y Y,Que Z B,Wang X D,et al.Research on sphericization of polyimide[J].Chemical Journal of Chinese Universities,2008,29(10):2091-2095.
[3]Zhao G,Ishizaka T,Kasai H,et al.Fabrication of unique porous polyimide nanoparticles using a reprecipitation method[J].Chem.Mater.,2007,19:1901-1905.
[4]Frank H,Ziener U,Landfester K.Formation of polyimide nanoparticles in heterophase with an ionic liquid as continuous phase[J].Macromolecules,2009,42:7846-7853.
[5]Kasai H,Mitsui H,Zhao G,et al.Fabrication of porous nanoscale polyimide structures[J].Chem.Lett.,2008,37:1056-1057.
[6]Jing J,Ding S,Zhang C,et al.Fabrication of size-controllable hollow nano-spheres based on polyimides composites[J].Mater.Chem.Phys.,2009,116:330-334.
[7]卢建军,赵晓博,刘妙青.反相非水乳液法制备聚酰亚胺微球[J].高分子学报,2010(12):1479-1482.Lu J J,Zhao X B,Liu M Q.Preparation of polyimide microspheres in non-aqueous inverse emulsion[J].Acta Polymerica Sinica,2010(12):1479-1482.
[8]Yang Y,Jia Z,Wang Y,et al.Preparation of hemispherical polyimide particles by inverse emulsion technique from poly(amic acid)ammonium salts[J].Colloid Polym.Sci.,2013,291:1049-1055.
[9]Ma L,Yang Y,He C,et al.In situ preparation and characterization of polyimide/silica composite hemispheres by inverse aqueous emulsion technique and sol-gel method[J].Colloid Polym.Sci.,2015,293:1281-1287.
[10]尚小琴,童张法,龚福忠,等.含固相淀粉的反相乳液体系稳定性研究[J].高分子材料科学与工程,2007,23(3):70-73.Shang X Q,Tong Z F,Gong F Z,et al.The stability of inverse emulsion including starch granule[J].Polymer Materials Science&Engineering,2007,23(3):70-73.