Preparation And Properties Of Polyphenylene Ether / Thermosetting Resin Cured For High Frequency Copper Clad Laminate

Copper Clad Laminate is an important basic material for the electronics industry.It is used in the manufacture of printed circuit board?PCB?which is widely used in computers,cell phones,televisions and other electronic products.With the high speed and high frequency development of electronic industry,more stringent requirements are proposed for the performance of the substrate-coated copper sheet:Both the excellent thermal stability,the smaller dielectric loss and the lower dielectric constant are needed to ensure the signal transmission speed and quality,which undoubtedly need to improve the performance of matrix resin.While the copper clad laminate made of phenolic resin or epoxy resin as matrix material has poor dielectric properties under high frequency working environment,which cannot meet the requirements of current high-frequency copper clad laminate for matrix materials.Polyphenylene oxide?PPO?is a high performance resin with a glass transition temperature of 210?,a dielectric constant of 2.45?1 MHz?,a loss factor of 7×10^-4?1 MHz?,good dimensional stability,and it is an important high temperature resistant resin which is widely used in low dielectric loss of printed circuit board.Therefore,the following two aspects are carried out in this study.1.In order to improve the dielectric properties and heat resistance of epoxy E-51 resin,and also improve the PPO poor film-forming and poor solvent resistance defects,MPPO,which obtained by the redistribution of PPO resin,was used as the modifier of epoxy E-51 resin and the curing composite agent was prepared.The molecular weight and chemical composition of PPO and MPPO were analyzed by gel permeation chromatography?GPC?and Fourier transform infrared spectroscopy?FT-IR?.The chemical composition,microstructure and thermal stability of the MPPO/E-51 system were analyzed by FT-IR,scanning electron microscopy?SEM?and TG system;the dynamic thermal mechanical properties?DMA?,mechanical properties,thermal conductivity and dielectric properties of the MPPO/E-51 system were also studied.The results showed that the amount of BPA used for redistribution not only affects the molecular weight,and also introduces a large number of phenolic hydroxyl groups in the system,and the molecular weight distribution was obviously narrowed.When the amount of BPA was 20 wt.%of PPO,MPPO had the lowest molecular weight of 2652.7.Reducing the molecular weight of PPO promotes its compatibility with E-51;Compared with the pure epoxy phase,the heat resistance of the MPPO/E-51 system is improved,and the maximum thermal weight loss temperature(Td₅₀%)is 421.02?;The MPPO/E-51 system can effectively improve the glass transition temperature of E-51,the highest reaching 151?.The bending strength of the MPPO/E-51 system is slightly lower than that of the pure E-51,but it still meets the requirements of the copper cladding plate.The thermal conductivity of MPPO/E-51 system is slightly lower than that of pure E-51,but it is still in the range of copper clad laminate.The MPPO/E-51 system has the lowest dielectric constant of3.76/10⁷ Hz and the lowest dielectric loss of 2.11×10^-3/10⁷ Hz.2.In order to overcome the shortcomings of the traditional matrix resin,but also to maintain excellent dielectric properties and thermal properties,the MPPO/BADCy curing resin was prepared by blending bisphenol A?BPA?cyanate ester resin?BADCy?with PPO.The microstructure of the cured resin system was analyzed by SEM.The DMA,mechanical properties,thermal conductivity and dielectric properties of the cured resin system were also studied.The results show that the reduction of PPO molecular weight effectively promoted the compatibility with BADCy.Compared with the pure BADCy resin,the glass transition temperature?Tg?of MPPO/BADCy curing resin decreased significantly,reaching a minimum of230?.The bending strength and thermal diffusivity of MPPO/BADCy resin system decreased slightly comparing with pure resin,but still met the requirements of CCL usage.The lowest permittivity of cured resin system is 3.85/10⁷ Hz and the lowest dielectric loss is 2.64×10^-3/10⁶ Hz.