Today's KNOWLEDGE Share : 3D-printable transparent block copolymer resin via photopolymerization-induced microphase separation

Today's KNOWLEDGE Share

Impact-resistant, haze-free, 3D-printable transparent block copolymer resin via photopolymerization-induced microphase separation

Incorporating rubbery domains into glassy polymers is an effective route to improve toughness and impact strength. However, retaining the transparency of the composite material over a wide temperature range with enhanced mechanical attributes is challenging because of a mismatch in refractive indices with changing temperatures, limiting their applications as optical materials.

Here, we report photopolymerization-induced microphase separation as a strategy for the fabrication of transparent, temperature-resistant nanostructured polymeric materials. Taking poly(methyl methacrylate) (PMMA) as the glassy component for its renowned high transparency, we perform controlled radical polymerization upon light exposure to transform the whole polymerization mixture into a cross-linked block polymer material, where a bicontinuous nanostructure consisting of PMMA and cross-linked rubbery microdomains spontaneously arises during polymerization in situ. The facile formation of the rubbery domains, smaller than 50 nm yet 3D continuous and cross-linked, is the key to retaining transparency above 120 °C in the visible light wavelength with dimensional stability and allowing efficient stress dissipation through the large interfacial area. We further demonstrate the 3D printability of the nanostructured materials into custom shapes via direct ink writing.

DOI: https://doi.org/10.1038/s41427-025-00618-3

source : Nature