| Epoxy resins (EP) are much, cheap and easy to process, so FR-4 made of epoxy resin has been widely used as copper clad laminate (CCL). However, epoxy resins have an undesirably high dielectric constant, high dielectric loss tangent, low thermal stability, unsatisfactory dimensional stability and inherent brittleness, limiting threir application in high-performance CCL materials. Poly (2, 6- dimethyl-1, 4-phenylene ether)(PPE) is a kind of thermoplastic resin with low dielectric constant, low water absorption, excellently thermal and mechanical properties, and EP can be modified using PPE to overcome the disadvantages mentioned above, to obtain a resin system with high performance. There are some major shortcomings existing in PPE/EP system, such as poor compatibilization, solvent resistance. The properties of CCL are mostly determined by the basic properties of the resins, so studying the properties of PPE/EP system has important academic and practical significance.Considering the poor compatibilization and solvent resistance of PPE/EP system, adding home-made compatibilizer SMA to PPE/EP system and simultanously adding TAIC (triallylisocyanurate), were found to be able to improve satisfactorily the compatibilization and solvent resistance of PPE/EP system.The curing reaction of PPE/EP system has been studied by nonisothermal DSC and isothermal DSC methods. PPE content has important effect on cure kinetic characteristics. The apparent activation energy values of PPE/EP system with PPE content of 10 wt %,20wt % and 40 wt % obtained by Kissinger treatment are equal to 63.88,55.37 and 47.31kJ/mol, respectively. PPE can accelerate the curing process of epoxy resin. The isothermal DSC results indicate that in all the temperatures investigated, higher isothermal temperature results in higher reaction rate and higher ultimate conversion.The properties of PPE/EP system have been studied carefully. PPE/EP system exhibits a typical upper critical solution temperature behavior. With increasing PPE content, heat resistance and dielectric properties increase. The tensile strength increases with the curing temperature and is strongly dependent on it. While the tensile modulus approximately exhibit the same, irrespective of cure temperature and composition. Fracture toughness for blends is dominated by the mechanical properties of thermoplastic PPE. Morphology characterized by SEM and TEM shows that the phase separation takes place via spinodal decomposition, and insignificant cross-links occurred between PPE and EP. Adding TAIC to PPE/EP systems can greatly improve solvent resistant of the blends. The size of the dispersed phase increases with increasing PPE content. Phase inversion takes place in about 30%PPE for PPE/EP blends.Temperature, pressure and time have important effects on the performances of PPE/EP composites. The optimum technical parameters for heat pressing molding are below: rising in temperature from room temperature to 150℃, then adding pressure to 1MPa in 25min, after that, 190℃/0.5h/1MPa following by 240℃/2.5h/5 MPa.The effects of heat pressing molding, resin content, silane coupling agent type and content on mechanical properties and dielectric properties of PPE/EP CCL were also studied. Manufactured PPE/EP CCL properties are better than those of FR-4.The compatibilization and its mechanism of styrene-maleic anhydride copolymer (SMA) to PPE and EP were studied. SMA was prepared through solvent polymerization. PPE was miscible with SMA over the entire composition with a low content of maleic anhydride of about 7%. SMA can be used as a kind of effective compatibilizer, but don't improve the solvent resistance of PPE/EP blends. The heat resistance of PPE/EP blends increases with increasing PPE content. The flexural strength of PPE/EP CCL increases with increasing SMA content, while water resistance decreases with the SMA content.Cured PPE/TAIC blends exhibit good chemical resistance, and heat stability increases with increasing PPE content. A-172 is a kind of effective silane coupling agent for PPE/TAIC composites. PPE/TAIC CCL is better than the CCL based on PPE/EP system, but the heat resistance of PPE/TAIC CCL is poorer.
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