用于UV树脂改性的可溶性聚酰亚胺的制备工艺

Preparation Technology of a Soluble Polyimide Used for UV Resin Modification

针对环氧丙烯酸树脂在应用于柔性电路板UV光固化阻焊油墨时所表现出的柔韧性、耐热性等方面的不足,通过不同单体组合和亚胺化法制备出一种具有合适分子量和耐热性良好的可溶性聚酰亚胺,并用其对环氧丙烯酸树脂改性.结果表明：制备该聚酰亚胺（PI）的较佳工艺过程为在0℃的温度下将摩尔比为1∶0.505∶0.505的3,4＇-ODA、BPDA、ODPA反应2 h合成聚酰胺酸（PAA）,再通过加入催化剂三乙胺和脱水剂乙酸酐的化学亚胺法在90℃将聚酰胺酸脱水4 h合成聚酰亚胺.该条件下合成的聚酰亚胺分子量为2.64×10^4,分解温度为508℃,用于环氧丙烯酸树脂改性使产物分解温度由原来的291℃提升至374℃,耐热性有所提高.

Epoxy acrylic resin has the shortcoming of the heat resistance and flexibility,when it was used in UV curable solder resist ink for flexible circuit board. A soluble polyimide with suitable molecular weight and good heat resistance was prepared to modify the epoxy acrylic resin. The souble polyimide（ PI） with different monomer combinations was made by different imidization methods. The better preparation process of polyimide was determined. Firstly,the polyamic acid（ PAA） was synthesized by 3,4＇-ODA、BPDA、ODPA,of which the molar ratios was 1∶ 0. 505∶ 0. 505,at 0 ℃ about 2 h,and then the polyamic acid was used to make polyimide（ PI） with the triethylamine as catalyst and acetic anhydride as dehydrating agent at 90 ℃ about 4 h. The molecular weight of this PI was 2. 64 × 10^4,and its decomposition temperature was 508℃. The decomposition temperature of epoxy acrylic resin modified by the souble PI was improved from 291 ℃ to 374 ℃ and its heat resistance was improved.