Synthesis and properties of flame‐retardant epoxy resins based on DOPO and one of its analog DPPO
Tóm tắt
Two phosphorus‐containing heterocyclic flame retardants ‐9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) and 2,8‐dimethyl‐phenoxaphosphin‐10‐oxide (DPPO) ‐ and their derivatives were characterized and incorporated in the backbone of epoxy novolac to obtain flame‐retardant epoxy resins. The structures and spectroscopic data including high‐resolution mass spectroscopy of these flame retardants were determined. Flame‐retardant epoxy resins with a phosphorus content of up to 2% based on heterocyclic DOPO and DPPO were cured with 4,4′‐diaminodiphenylmethane (DDM), and their features were examined by UL 94, LOI, and DSC. In this manner, high‐performance polymers with glass transition temperatures around 190°C and the UL 94 rating V0 were obtained. These polymers were compared with epoxy resins incorporating diphenyl phosphite and diphenyl phosphate, which are nonheterocyclic and do not pass the UL 94 test up to 2% phosphorus. DPPO has a similar flame retardancy like the commercially available DOPO. Furthermore, to explain the difference in the efficiency of the tested flame retardants, key experiments for the determination of the active species during the flame‐retarding process were performed and the PO radical was identified. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007.
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Tài liệu tham khảo
Muskof J. W., 1987, 547
Varma I. K., 2000, J Macromol Sci Polym Rev C, 42, 139
Lengsfeld H., 2004, Kunststoffe, 10, 300
Deutsches Institut für Normung e.V., 1999, DIN IEC 60695‐11‐10
Deutsches Institut für Normung e.V., 1994, DIN 53765
Deutsches Institut für Normung e.V., 1999, DIN EN ISO 4589‐2
SADABS Siemens Area Detector Absorption Correction Program 1997.
Sheldrick G., 1997, SHELX 97
Wang C. S.;Shieh J. Y.Jpn. Pat. 2 001 220 427 (2001).
Wang C. S.;Hsieh C. Y.;Lin C. Y.Jpn. Pat. 2 003 105 058 (2003).
Kinoshita H.;Makino T.;Yamashita T.;Midori K.;Ikemoto K.;Sumitomo H.Jpn. Pat. 2 002 275 473 (2002).
Taniguchi A.;Sakai S.;Okamoto T.WO. Pat. 2 005 052 055 (2005).
Gan J.;King B. A.;Groot N. H.;Maecker N. L.;Tinetti S. M.;Stobby W. G.WO. Pat. 2 003 102 060 (2003).
Saito T.DE. Pat. 3 010 375 (1980).
Hörold S.DE. Pat. 19 613 066 (1997).
Buysch H. J.;Glock V.;Griehsel B.;Komoschinski J.DE. Pat. 19 505 352 (1996).
Döring M.Proceedings of the Flame Retardants Conference: London 2006 p163. ISBN: 0‐9541216‐7‐8.
Döring M., 2005, 16th BCC Conf Flame Retardancy, 16, 83