共聚酰亚胺及其应变基底胶的研究

STUDY ON THE COPOLYIMIDE AND USED FOR A LASE MATERIAL OF THE STRAIN GAUGE

以多相溶液共聚合研制了其共聚酰亚胺(CPI)具有很高粘结力的共聚酰胺酸(CPAA)型应变基底胶。研究发现,原料组分、热亚胺固化温度(T_i)、溶剂种类和少量酚醛树脂(PF)对CPAA固相热亚胺(固)化过程和对CPI的粘度(η_i)、粘结性及T_g等均有明显影响。确定了最佳工艺条件,并以此制造了具有高精度的应变计。

The copolyamic acid (CPAA) were prepared from two or three aromatic anhydrides with an aromatic p, p -diamine by copolymerization in different solvents in order that the adhesion raise of the Polyimide (PI) and make for as an adhesive which used as a base material of the strain gauge.The various factors on the characterization of Process of thermal imidization in solid-state that conversion from CPAA to copolyimide (CPI)and the Properties of CPI have been ive-stigated.It was found that the adhesion of CPI is changed with the components of raw material and have a highest peak in B 60-70 molar %, and the viscosity (ηi)and the adhesion of CPI are changed with the .temperature (Ti) of the imidization (cure)and have a-highest peak on both by oneself and the corresponding temperature Tin and Tic, the difference between Tin and Tie is about 50℃it is affirmed that Tic ( 230-250℃) is a suitable temperature of imidization (cure) which generally appear over the Tiη about 50℃Free solvents DMF<DMAc<NMP is arranged in the increasing and Promoting action for both adhesion and imidization.The mixture of the CPAA with little PF resin used as base adhesive show small change form and higher elastic modulus of strain gauge at the high temperature,A suitable technical conditions were affirmed as an application of strain adhesive for make strain gauges with higher accuracy.