聚酰胺−酰亚胺材料腐蚀及老化特性研究

Corrosion and Aging Characteristics of Polyamide-imide Materials

将聚酰胺−酰亚胺材料进行霉菌、高温热老化试验及吸湿试验,并采用力学性能测试、玻璃化转变温度测试、表面形貌观察、红外光谱分析等方法,研究聚酰胺−酰亚胺材料的腐蚀老化特性。结果表明:聚酰胺−酰亚胺材料霉菌试验后外观颜色基本不变,拉伸强度有所降低,而延伸率稍有增加;热老化试验后,材料颜色由黄绿色变为棕色,拉伸强度和延伸率基本不变,而玻璃化转变温度有所升高,聚酰胺−酰亚胺中主要的酰亚胺结构、酰胺键和苯环结构均未发生改变;长时吸水后,聚酰胺−酰亚胺材料的拉伸强度降低,且随着湿度提高,强度下降趋势变大,材料弹性模量随着湿度增加而增大,但水分子不与聚酰胺−酰亚胺发生化学反应,水分除去后,材料的尺寸及性能恢复到原始水平。

The polyamide-imide material was subjected to mold test,high temperature thermal aging test and moisture absorption test.The mechanical property test,glass transition temperature test,surface morphology observation,infrared spectrum analysis and other tests were used to study the corrosion aging properties of the polyamide-imide material.The results show that the appearance color of the polyamide-imide material was basically unchanged after the mold test,and the tensile strength reduced,the elongation slightly increased.After the heat aging test,the material color changed from yellow-green to brown,and the tensile strength and elongation were basically unchanged,but the glass transition temperature increased.The main imide structure,amide bond and benzene ring structure in polyamide-imide did not change.After long-term water absorption,the tensile strength of polyamide-imide material decreased,and the strength decline trend became larger and the elastic modulus of the material increased with the increase of humidity.However,the water molecules did not chemically react with the polyamide-imide.After removal of the moisture,the dimensions and properties of the material returned to their original levels.