The effect of pre‐curing UV‐irradiation on the crosslinking of silicone rubber

Abstract

A recent work made use of selective pre-curing UV-irradiation and its effect on the kinetics of reaction of heat-cure silicone elastomers to spatially tune its viscoelastic properties and design architected solid membranes. The present study adds to the possibility of controlling the local properties of spatially graded materials by exploring the effect of key processing parameters such as the UV dose and the silicone mix thickness on the vulcanization kinetics. Dynamic Differential Scanning Calorimetry measurements have been performed showing that, over the conditions explored, the higher the UV dose, the slower the kinetics reaction. Additionally, complete crosslinking was always reached. Companion modeling effort using the Kissinger reaction model is attempted and the effects of processing parameters on the apparent activation energy are discussed. This work is a crucial first step towards the control of the processing settings needed to design architected silicone rubber membranes with spatially controlled mechanical property gradients obtained from a unique macromolecular network.

Photopatterning of PDMS Films: Challenging the Reaction between Benzophenone and Silicone Functional Groups

“…This scenario tends to further demonstrate why the curing time, rather than the irradiation dose or the stoichiometry of benzophenone to reactive radicals, is such a crucial point in the process first presented by other research teams. We are currently trying to adapt this process to the photopatterning of RTV formulations [29,30].…”

A facile and efficient strategy for fabrication of silicone rubber foam based on in situ precuring‐supercritical CO2 foaming technology

“…The precuring degree of silicone rubber compounds was measured by a differential scanning calorimetry (Netzsch DSC 214, Germany) at a heating rate of 10°C/min. The precuring degree value was calculated by Equation () 28 where α is the precuring degree of the sample, ∆H t is the exothermic enthalpy of precuring reaction, and ∆H total is the complete curing reaction exothermic enthalpy of the uncured sample, ∆H total = 10.86 J/g.…”