Hollow spheres of aromatic polyamide prepared by reaction‐induced phase separation

Abstract

Hollow spheres of aromatic polyamide are obtained by the reaction-induced phase separation during polymerization of 5-hydroxyisophthalic acid and 1,4-phenylene diamine in an aromatic solvent at a concentration of 1-2% at 320 C without stirring. The hollow sphere has a dimple hole and the diameters of the hollow spheres are 3-4 lm. The droplets are initially generated via liquid-liquid phase separation and then rigid crosslinked network structure formed the rigid skin layer on the surface of the droplets. The solidification of the droplets occurred owing to the further polymerization in them with maintaining the morphology to form the hollow spheres. The hollow spheres exhibit outstanding thermal stability. 14 Although the rigid polyimides exhibit poor tractability, hollow spheres can be prepared using the soluble precursor poly(amic acid)s. However, many of other aromatic polymers show neither fusibility nor solubility owing to their rigidity and it is too difficult to control the morphology precisely.

Millimeter‐size polyethylene hollow spheres synthesized with MgCl2‐supportedZiegler‐Natta catalyst

“…In recent years, preparation and properties of hollow or multihollow polymer spheres or beads have received increasing attentions . Applications of these materials include absorbents, carriers of drug delivery systems, supports of catalysts, sound absorption materials and thermal insulation materials.…”

“…In recent years, preparation and properties of hollow or multihollow polymer spheres or beads have received increasing attentions. [20][21][22][23][24][25][26] Applications of these materials include absorbents, carriers of drug delivery systems, supports of catalysts, sound absorption materials and thermal insulation materials. Because of the highly hydrophobic and partially crystalline characters of polyolefin materials, hollow spheres based on polyolefins may present more interesting properties and find new applications as compared to the hollow spheres based on polar polymers and amorphous V C 2015 Wiley Periodicals, Inc.…”

Asymmetric electrochemical polymerization in cholesteric liquid crystalline media: Effect of isomeric structures of chiral inducers containing bornyl group

“…Highly-ordered structure in polymers has a great advantage for obtaining macroscopic properties such as ionic conduction [1], mechanical properties [2] and characteristic morphorogies [3]. Many approaches for controlling highly-ordered structure of conjugated polymers have been examined [4][5][6][7].…”

Consideration on formation mechanism of aromatic polyamide hollow spheres prepared by reaction‐Induced phase separation

“…Recently, poly(1,4‐phenylene‐5‐hydroxyisophthalamide) (PPHIA) hollow spheres have been prepared by means of reaction‐induced phase separation during direct polymerization of 5‐hydroxyisophthalic acid (HIPA) and 1,4‐phenylene diamine (PPDA) as shown in Figure (a) . These hollow spheres exhibited neither fusibility nor solubility, and thereby they were thermally and chemically stable.…”

“…Even though microspheres of several rigid aromatic polymers had been prepared so far, [7][8][9][10][11][12][13][14] only aromatic polyimide hollow spheres had been successfully prepared by using the soluble precursor poly(amic acid)s. [15][16][17][18][19][20][21] Recently, poly(1,4-phenylene-5-hydroxyisophthalamide) (PPHIA) hollow spheres have been prepared by means of reactioninduced phase separation during direct polymerization of 5-hydroxyisophthalic acid (HIPA) and 1,4-phenylene diamine (PPDA) as shown in Figure 1(a). 22 These hollow spheres exhibited neither fusibility nor solubility, and thereby they were thermally and chemically stable. The reaction-induced phase separation during polymerization is not limited by the intractability of polymers and this procedure has great potential to prepare hollow spheres of intractable polymers.…”