Thiol–enes are a group of alternating copolymers with highly ordered networks and are used in a wide range of applications.Here,“click”chemistry photostructuring in off-stoichiometric thiol–enes is shown to induce...Thiol–enes are a group of alternating copolymers with highly ordered networks and are used in a wide range of applications.Here,“click”chemistry photostructuring in off-stoichiometric thiol–enes is shown to induce microscale polymeric compositional gradients due to species diffusion between non-illuminated and illuminated regions,creating two narrow zones with distinct compositions on either side of the photomask feature boundary:a densely cross-linked zone in the illuminated region and a zone with an unpolymerized highly off-stoichiometric monomer composition in the non-illuminated region.Using confocal Raman microscopy,it is here explained how species diffusion causes such intricate compositional gradients in the polymer and how offstoichiometry results in improved image transfer accuracy in thiol–ene photostructuring.Furthermore,increasing the functional group off-stoichiometry and decreasing the photomask feature size is shown to amplify the induced gradients,which potentially leads to a new methodology for microstructuring.展开更多
基金This project was funded by the European Research Council through the European Research Council Advanced grant XMEMS(No.267528).
文摘Thiol–enes are a group of alternating copolymers with highly ordered networks and are used in a wide range of applications.Here,“click”chemistry photostructuring in off-stoichiometric thiol–enes is shown to induce microscale polymeric compositional gradients due to species diffusion between non-illuminated and illuminated regions,creating two narrow zones with distinct compositions on either side of the photomask feature boundary:a densely cross-linked zone in the illuminated region and a zone with an unpolymerized highly off-stoichiometric monomer composition in the non-illuminated region.Using confocal Raman microscopy,it is here explained how species diffusion causes such intricate compositional gradients in the polymer and how offstoichiometry results in improved image transfer accuracy in thiol–ene photostructuring.Furthermore,increasing the functional group off-stoichiometry and decreasing the photomask feature size is shown to amplify the induced gradients,which potentially leads to a new methodology for microstructuring.