Application of Sorbitol Mixture Self-healing glass for 3D printing

Recently, researchers from Taiwan’s National Central University developed a UV-resistant, heat-resistant, self-healing emulsion glass. An impressive library of properties makes Liquid Solid (LLS) materials ideal for support media, allowing UV and thermoset inks (also known as resins) to be “3D written” directly into it and cured independently of the surrounding LLS.

Many mechanical tests were performed on liquid glass to determine its suitability for supporting media. National Central University photo. Liquid-like solids and 3D writing According to the researchers, LLS materials can be used as a strong support medium for liquid inks. Using them to hold the ink in place while it cures helps maintain the intended writing geometry. Without a supporting medium, the ink’s gravity and surface tension can cause fluid instability (thermal chaos). For example, PDMS (an elastomer) is biocompatible, nontoxic, and optically clean, making it useful in lubricants and defoaming agents. Despite its UV and thermoset properties, its applications are largely limited to its fluid form due to its extremely low prepolymer viscosity and long cure time. So, by itself, it cannot maintain the desired 3D shape long enough for it to solidify, making it very difficult to 3D print.

Recently, this problem was solved by writing liquid PDMS3D into the LLS holding medium and solidifying it after suspending it. Self-Healing Emulsion Glass To develop the next generation support medium, the research team first mixed a specially formulated silicone oil with sorbitol and water to form an aqueous solution. From this, they extracted a “stable latex glass” and used it as a support medium for their experiments. The team chose to use PDMS elastomer as the ink, which was 3D written into latex glass and cured. The 3D writing device (a syringe pump with a nozzle diameter of 1.83mm) was built from the ground up. The 3D structures were modeled and written into latex glass samples and cured with heat and UV light to demonstrate the suitability of the glass as a support medium. For the UV process, a 365nm UV lamp was used for 60 seconds, and for the thermal process, the ink glass samples were heated in an oven at 100°C for 1 hour. Even after six UV and heat exposures, latex glass remains phase-free and maintains its structural integrity, making it UV and heat resistant. This means the glass can be used to cure UV and thermal inks simultaneously.