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Idesaki, Akira; Uechi, Hiroki*; Hakura, Yoshihiko*; Kishi, Hajime*
JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 29, 2015/03
Effects of gamma-ray irradiation on a cyanate ester/epoxy resin composed of dicyanate ester of bisphenol A (DCBA) and diglycidyl ether of bisphenol A (DGEBA) was investigated by changes in physicochemical properties such as gas evolution behavior, change in chemical structure, and so on, after the gamma-ray irradiation with dose of 100 MGy as maximum under vacuum. It was found that ether linkages are mainly decomposed by the gamma-ray irradiation with evolving gases of hydrogen, carbon dioxide and carbon monoxide and decreasing in glass transition temperature.
-ray irradiation on a cyanate ester/epoxy resinIdesaki, Akira; Uechi, Hiroki*; Hakura, Yoshihiko*; Kishi, Hajime*
Radiation Physics and Chemistry, 98, p.1 - 6, 2014/05
Times Cited Count：24 Percentile：87.38(Chemistry, Physical)Effects of -ray irradiation on a cyanate ester/epoxy resin composed of dicyanate ester of bisphenol A (DCBA) and diglycidyl ether of bisphenol A (DGEBA) was investigated by changes in physicochemical and mechanical properties after the -ray irradiation with dose of 100 MGy as maximum at ambient temperature under vacuum. After the irradiation, gases of hydrogen, carbon monoxide and carbon dioxide were evolved, glass transition temperature decreased, and flexural strength also decreased. It was concluded that ether linkages bonded to cyanurate, isocyanurate and oxazolidinone structures are mainly decomposed by the irradiation. After 100 MGy irradiation, the flexural strength of DCBA/DGEBA was maintained more than 170 MPa which is 90% of initial value of 195 MPa.
-raysUechi, Hiroki*; Hakura, Yoshihiko*; Nakagawa, Takaharu*; Matsuda, Satoshi*; Kishi, Hajime*; Idesaki, Akira; Oshima, Takeshi
no journal, ,
Cyanate/epoxy resins are expected to use as insulating material of a superconducting magnet system in a proton accelerator. However, there are little reports on the radiation resistance of the resins. In this work, -ray irradiation effect on the cyanate/epoxy resins in which molecular structures of cyanate and epoxy were varied was investigated by gas analysis, dymanic visco-erastic test, and so on. It was found that glass transition temperature (Tg) of all resins dicreased and that the behavior of Tg was different among the resins. This suggests that there is a relationship between the molecular structure and radiation resistance of the cyanate/epoxy resins.
-ray irradiationUechi, Hiroki*; Idesaki, Akira; Hakura, Yoshihiko*; Matsuda, Satoshi*; Kishi, Hajime*
no journal, ,
Cyanate/epoxy resins are expected to be applied to an electrical insulating material for accelerator, fusion reactor, and so on. However, there are few reports on property change of the resins by radiation. In this work, effect of -ray irradiation on the properties of cyanate/epoxy resin was investigated. It was found that bending modulus and density of the cyanate/epoxy resin increased after the irradiation. This is considered to suggest that nano-voids in the resin decrease due to rupture and recombination of crosslinking between cyanate and epoxy.
Idesaki, Akira; Hakura, Yoshihiko*; Uechi, Hiroki*; Oshima, Takeshi; Kishi, Hajime*
no journal, ,
Relationship between chemical structure of hardeners for epoxy resins and radiation resistance of obtained resins was investigated by gas analysis, bending test, dynamic viscoelasticity measurement, and so on. It was found that epoxy resins which were cured by hardeners containing benzene ring and/or C-N bond in the structure. Especially, epoxy resin which was cured by cyanate ester showed the highest radiation resistance.
-rays on cyanate ester / epoxy resinsIdesaki, Akira; Uechi, Hiroki*; Hakura, Yoshihiko*; Matsuda, Satoshi*; Kishi, Hajime*
no journal, ,
Cyanate ester / epoxy resins are expected to be applied for electrical insulating material used in a superconducting magnet system at J-PARC muon beam line. In this work, radiation degradation mechanism of cyanate ester / epoxy resin was investigated. It was found that crosslinking structure formed between cyanate ester and epoxy is disintegrated by -ray irradiation and gases of hydrogen, carbon dioxide, and so on, evolve. While flexural strength of resin after the irradiation decreased, the resin retained its flexural strength of 180 MPa which is about 90% of initial value.
Arimura, Ken*; Idesaki, Akira; Uechi, Hiroki*; Hakura, Yoshihiko*; Kishi, Hajime*
no journal, ,
Effect of hardeners with different chemical structure on radiation resistance of cured epoxy resins was investigated by gas evolution. 4,4'-diaminodiphenylmethane (DDM), 2,4,6-tris(dimethylaminomethyl)phenol (TDMP), hexahydrophtalic anhydride (HHPA) and phenol novolac (PN) were examined as hardener. The epoxy resins cured by DDM, TDMP and PN which contain C-N bonds or benzene ring in the structure showed small amount of evolved gases after the irradiation.
