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采用均苯四甲酸二酐(PMDA),4,4’-二氨基二苯醚(ODA)为单体,甲醇、四氢呋喃组成的混合溶液为溶剂,进行缩聚反应合成聚酰亚胺(PI)的预聚体聚酰胺酸,经过两步法亚胺化得到PI粒子。红外光谱(FT-IR)对聚合物进行表征,表明经过两步法亚胺化(化学亚胺化和热亚胺化)才能使聚酰胺酸完全亚胺化;扫描电镜(SEM)图片显示,当四氢呋喃/甲醇(THF/MeOH)比例为7∶3可得到粒径为5～10μm且分散性好的PI粒子;利用热失重分析(TGA)可知T5d为530℃,T10d在560℃,PI粒子具有优良的热稳定性。
Polyimides (PI) were synthesized by polycondensation using a mixed solution of pyromellitic dianhydride (PMDA), 4,4’-oxydianiline (ODA) as a monomer and methanol and tetrahydrofuran as a solvent Prepolymer Polyamic acid, imidized in two steps to give PI particles. The FT-IR spectra of the polymer showed that imidization of polyamic acid was completely imidized by two-step imidization (chemical imidization and thermal imidization) When the molar ratio of tetrahydrofuran / methanol (THF / MeOH) is 7: 3, PI particles with 5 ~ 10μm particle size and good dispersibility can be obtained; T5d is 530 ℃ and T10d is 560 ℃ by thermogravimetric analysis (TGA) Has excellent thermal stability.