摘要 |
A MULTI-FUNCTIONAL EPOXY RESIN WITH GOOD HIGH TEMPERATURE PROPERTIES ALLOWING PROLONGED SERVICE AT TEMPERATURE ABOVE 120°C IS DERIVED FROM A PRECURSOR OF FORMULA (I): FORMULA 1 IN WHICH R3 TO R8 INCLUSIVE ARE INDEPENDENTLY SELECTED FROM HYDROGEN, C1 TO C3 ALKYL OR HALO-ALKYL AND R9 IS HYDROGEN, ALKYL OR HALOGEN, AND IN WHICH N HAS THE VALUE 0, 1 OR 2. THE PRECURSOR (1) MAY BE SELF-COUPLED OR CROSS-COUPLED WITH PRECURSOR OF OTHER EPOXY COMPOUNDS OF THE TGDDM TYPE. SUCH CROSS-COUPLING GIVES RISE TO A COMPLEX MIXTURE CONTAINING NOT ONLY THE MIXED PRODUCT, BUT ALSO THE SELF-COUPLED PRODUCTS OF EACH CONSTITUTENT. REGARDLESS OF THE PRECISE CHEMICAL MAKE-UP OF THE MIXTURE, THE OBSERVED GLASS TRANSITION TEMPERATURE IS HIGHER THAN FOR TGDDM RESINS FORMED WITHOUT PRECURSOR (I). IF THE SUBSTITUENT AT THE R9 POSITION IS ALKYL OR HALOGEN, OLIGOMER FORMATION IS SUPPRESSED AND A LESS COMPLEX MIXTURE RESULTS.
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