The Preparation And Properities Of Polyimide And High Performance 2-layers Flexible Copper Clad Laminate

Flexible copper clad laminate (FCCL) is the one of the super hybrid materials for flexible printed circuit board with high performance, outstanding portability, perfect flexibility, and high thermal resistant ability and even can be printed to make Flexible printed Circuit Board (FCB) which is widely used as the raw materials for portable devices, flexible devices, military aerospace and etc. Recently,2F,2L-FCCL using polyimide performs well, and become a new tendency of this area.This article using ODPA, BPDA, PMDA, and BTDA as dianhydride and PDA, HDA, HEA, ODA, BAPP as diamine, we synthesized polyamic acid (PAA) under low temperature, fabricatied both aromatic and aromatic-aliphatic PAA, PI was obtained via coating method. 2L-FCCL was manufactured by thermal laminating method. PI used in 2L-FCCL with the best properties was modified by inorganic modification and improving technology. By adding inorganic materials to modify the properties of PI used in 2L-FCCL or coupling PI multiple layers or using non-air thermal treatment,3 kinds of 2L-FCCL were made. By utilizing Fourier transform infrared spectroscopy (FTIR), thermo mechanical analysis (TMA), thermo gravimetric (TG), scanning electron microscopy (SEM), X-ray Diffraction (XRD), polymerization situation of PAA solution and imization ratio, thermal resistance and electrical properties of PI film were characterized. By using SEM, electronic universal tensile testing machine and tin solid bath, the adhesive situation of conjunction layer of 2L-FCCL, the surface of peeling side, and the impact of the peeling strength were analyzed based on mechanism.The results show:of all the kinds PI, aromatic-aliphatic one is the best candidate with high performance over all the other polyimides for further use, especially the type ODPA-80%ODA-20%HDA has the most comprehensive properties. The precursor PAA has the apparent viscosity 79300cp, its T5% is 377.28℃, and the tensile strength is 87.63MPa. FCCL made from this PI film has the highest peel strength 1.37N/mm. By coupling PI multiple layers to make 2L-FCCL or using non-air thermal treatment treating 2L-FCCL, both CTE of PI decreased and the later one has the lowest CTE close to Copper film (17×10-6/k), the peel strength after thermal treatment still remain 1.0N/mm, it can pass Tin Solid Bath under 360℃ which means high thermal stability.