| Summary: | 碩士 === 國立成功大學 === 化學工程學系 === 88 === In this investigation, 9,10-Dihydro-9-oxa-10-phosphaphenthrene（DOP O）was directly reacted with Cresol novolac epoxy（CNE）to form a epoxy resins which contain phosphorus. We also used melamine, phenol, formalde- hyde to synthesize a condensation polymer（MPN, Melamine Phenol Novolac） by the condensation polymerization. The condensation polymer MPN-1 and MPN-2 was used as a curing agent for CNE. All the structures of synthesized monomers were confirmed by IR、Mass、EA、NMR.
The epoxy resins C8（CNE with average functionality of 8）、C8P1（C8 with 1% phosphorus）、C8P2（C8 with 2% phosphorus）and C8P3（C8 with 3% phosphorus） were cured with various nitrogen content of MPN-1 and MPN-2 with 0.1 phr TPP（Triphenyl Phosphine） as curing accelerator. The kinetics of MPN-1 and MPN-2 with C8、C8P1、C8P2 and C8P3 were found to follow auto-catalytic model by DSC and this model was used to calculate the parameters and activation energies of curing reactions. We also use SEM to observe the morphology of the cured systems. The thermal、mechanical properties and flame retardancy of cured epoxy resins were evaluated by DMA、TGA、LOI and UL-94 tests. The results indicated that Epoxy/MPN-1 and Epoxy/MPN-2 systems exhibit higher Tg but lower thermal stability than epoxy/PN system. Furthermore, LOI value and char yield increased with the increase in phosphorus content of epoxy resins. The data implied that the used of MPN-1、MPN-2 to cure phosphorus-containing epoxy resins could achieve excellent flame retardancy with much smaller content of phosphorus than PN and this phenomenon was called N-P synergism. The use of N-P synergism also reduced moisture absorption by decreasing phosphorus content. Sofar, a cured epoxy system with high Tg、halogen-free and high reliability for PCB materials is obtained.
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