Control of reactivity of novolac resins: the use of 3,4-dihydro-2H-pyran as a labile protecting group

The control of the reactivity of novolac resins towards common crosslinkers through the use of 3,4-dihydro-2H-pyran as a protecting group is reported. This thermally labile protecting group is shown to be effective for the co ntrol of the cure of the novolac resin system through the use of models and on the resins themselves. The option of controlling the temperature of cur e of the resins through the manipulation of the pH of the reaction mixture is also reported. The control of the cure was measured by differential scan ning calorimetry (DSC). The use of the protecting group as a means to manip ulate the structure of the cured resins is discussed. (C) 2001 Elsevier Sci ence Ltd. All rights reserved.