Method for accelerating and quantifying setting of glue, useful e.g. in preparation of wood laminates, based on electrical heating

摘要

Process for accelerating and quantifying the kinetics of gluing by applying electrical energy. Process for accelerating and quantifying the kinetics of gluing by applying electrical energy comprises (1) preparing two supports by coating them with a glue of the aminoplast, phenoplast, vinyl or epoxy resin types; (2) placing a conductive textile covering (Te), containing an intrinsically conductive polymer (Pci), at the junction of the two glue layers; (3) fixing conductors to the ends of Te; (4) putting in place an electrical assembly (Me) through which current is applied; (5) stopping the flow of current after a heating time that corresponds to polymerization of the glue; and (6) disconnecting the electrical device. The current is such that V = (Pc.Rs)12L, where V = applied voltage; Rs = surface resistivity (ohm square); L = distance between connectors and Pc = power (W/m2). V is applied from a generator and during this phase V is measured with a voltmeter, while the current is measured with an ammeter and the temperature, T0, close to the junction of the glue layers, is determined with a thermocouple, or these last two are calculated using simple formulae. Temperature and time (t) for polymerization are determined as T0 = f(t), so an experimental law for the setting time is deduced, allowing quantification of this time for various classes of materials.