| Summary: | 碩士 === 國立中興大學 === 化學工程學系所 === 100 === Linear poly(ether sulfones) are generally prepared from equal molar of bisphenols and dihalides of diphenyl sulfone in the presence of base. Therefore, poly(ethers sulfones) with a residual phenol group in the repea ting unit are difficult to control. In this work, a phosphinate poly(ether su- lfone) (P1) with a phenol group in the repeating unit was prepared from a one-pot reaction of a 4,4''-dihydroxybenzophenone (DHBP)-based poly(e- ther sulfone), poly(oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1,4-ph- enylene-sulfonyl-1,4-phenylene (DHBP-PEEK), with 9,10-dihydro-oxa- 10-phosph aphenanthrene-10-oxide (DOPO) and phenol in the presence of H2SO4. The phenol linkages provide reacting cites with epoxy resins. Therefore, flexible and transparent films of epoxy thermosets can be pre- pared from the curing of P1 with epoxy resins, cresol novolac epoxy (C- NE) and diglycidyl ether of bisphenol A(DGEBA). A phosphinated pol- y(ether sulfone) (P2) with an amino group in the repeating unit was ate- mpted to prepare in a similar procedure except for the phenol is replaced by aniline. However, the reaction was not successfully. To achieve the go- al, a DOPO-diphenolaniline, 1,1-bis(4-hydroxyphenyl)-1-(4-aminopheny- l)-1-(6-oxido-6H -dibenz <c,e> <1,2> oxaphosphorin-6-yl)ethane, was prepared from the one-pot reaction of DOPO, DHBP and aniline in the presence of H2SO4 . P2 can successfully be prepared from the nucleophi- lic substitution of DOPO-diphenolaniline and difluorodiphenylsulfone (DFDPS) in the presence of K2CO3. P1/CNE, P1/DGEBA, P2/CNE, P2/DGEBA thermosets all show flexibility. The moderate-to-high mole- cular weight of P1 might be responsible for the flexibility (toughness), which is rarely seen in the low molecular weight curing agent/epoxy thermosets. P2 is brittle, but flexible film can be achieved by reacting the amine with dianhydride ODPA. After imidization at 300 oC (1h), the resulting P2/ODPA displays a Tg value as high as 340 oC by dynamic mechanical mechanical analysis. The data show the power of crosslinking.
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