| Summary: | 博士 === 國立臺灣大學 === 化學工程學系研究所 === 86 === In this study, two new types of phosphorus-containing epoxide and a anhydride
were prepared and used as reactive type flame retardants. The cyclic organic
phosphorus compound, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)
, was covalently incorporated into the molecular structures of epoxides and an
hydride as pendant group to improve the flame retardancy of epoxy-resin compos
ites. The structures of the obtained compounds were confirmed by mass, FTIR, 1
H, 13C, 31P-NMR spectroscopies, elemental analyses, and X-ray single crystal a
nalysis.An aryl phosphinate anhydride, (9,10-dihydro-9-oxa-10-phosphaphenanthr
ene-10-oxide)-methyl succinic anhydride (DMSA), was synthesized by the additio
n and dehydration reaction of DOPO with itaconic acid. Two kinds of epoxides,
DER 331 and DEN 438, were cured with different proportion of DMSA/PA and DMSA/
HHPA using a BDMA catalyst. The thermal and flame resistance of the epoxy-resi
n composites were evaluated by thermogravimetric analysis (TGA) and determinin
g their limiting oxygen index (LOI) value. The results showed that epoxy resin
s cured with DMSA exhibit higher LOI values and char yields compared with thos
e cured by commercial curing agents, such as PA and HHPA. Furthermore, LOI val
ue as well as char yield of the epoxy-resin composites increases with increasi
ng phosphorus content. The flame retardancy of the epoxy-resin composites were
significantly improved by using DMSA as curing agent.The first novel aryl pho
sphinate epoxide, 10-(2'',5''-diglycidyl ether phenyl)-9,10-dihydro-9-oxa-10-pho
sphaphenanthrene-10-oxide (DHQEP), was synthesized through the reaction of DOP
O with 1,4-benzoquinone, followed by glycidyletherification with epichlorohydr
in in excess and using sodium methoxide as a active agent. The second novel ar
yl phosphinate epoxide, 10-(2'',3''-diglycidyl ester propyl)-9,10-dihydro-9-oxa-
10-phosphaphenan-threne-10-oxide (DIAEP), was synthesized by the addition reac
tion of DOPO with itaconic acid, followed by glycidylesterification with epich
lorohydrin in excess and using a quaternary ammonium halide as active agent. I
n addition, compositions of the DHQEP and DIAEP with several anhydride and dia
mine curing agents, e.g., phthalic anhydride (PA), hexahydrophthalic anhydride
(HHPA), aryl phosphinate anhydride (DMSA), dicyanodiamide (DICY), 4,4''-diamin
odiphenylmethane (DDM), and 4,4''-diaminodiphenyl sulfone (DDS), were used for
making a comparison of its heat and flame retardancy with that of DER331 and D
EN438. The resulting aryl phosphinate epoxy-resin composites demonstrated a qu
ite high limiting oxygen index (LOI) value as well as high char yield, confirm
ing the effectiveness of aryl phosphinate epoxides as flame retardant for epox
y resins.
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