Studies on the reactive polyvinylidene fluoride-polyamide 6 interfaces: rheological properties and interfacial width

We firstly synthesized and characterized a series of functional carboxylated polyvinylidene fluoride (PVDF-g-AAc). Then the temporal change of the complex viscosity (η*) of the two plates consisting of the graft polymer PVDF-g-AAc and polyamide 6 (PA6) was measured by a rotational rheometer. There were two distinct stages for the change of the complex viscosity (η*) with time: (i) stage I, where η* increased rapidly at short times, a reaction-controlled kinetics was induced; (ii) stage II, where η* increased slowly at a long time, however, a diffusion-controlled kinetics was obtained. Despite whether the kinetics are reaction-controlled or diffusion-controlled, the reaction could be predicted by pseudo-first-order kinetics. Meanwhile, the reaction temperature had an effect on the interfacial width and roughness. The value of the interfacial root-mean-square (rms) roughness obtained from AFM was consistent with that of the interfacial width from ellipsometer at different temperatures.