Yue Xiao1 Zhihan Hong1 Garrett Coleman1 Qing Hao1 Rongguang Liang1 Pierre Lucas1

1, University of Arizona, Tucson, Arizona, United States

In recent years, tremendous efforts have been dedicated to the additive manufacturing, or three-dimensional (3D) printing of various polymers, for its extensive applications in bioengineering1,2, optics3 and other fields. Comparing with ultraviolet (UV) curing, laser curing with heat can avoid color changes by UV light and keep high optical transmissivity. However, the spatial resolution of laser heating is still on the order of millimeter4–6. In this work, a pulsed infrared (IR) laser is used for 3D printing of thermally curable polymers. With ultrafast heating, this technique can precisely control the polymer curing to achieve a minimum feature size of ~20 micrometers. Thermal simulations are carried out to better understand the thermal curing process, with the measured exothermal enthalpy of the polymer to improve the simulation accuracy. Various 2D and 3D patterns are fabricated based on polydimethylsiloxane, which can be used for optics and other relevant fields.

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