Enhancement of scratch resistance properties on the surface of photocurable 3D printed models through the integration of polysiloxane core–shell nanoparticles

Photocurable 3D printing technology has attracted widespread attention because of rapid formation speed and high printing accuracy, but photosensitive resin (PSR) materials with scratch resistance have become a difficult problem in 3D printing research. In this paper, polysiloxane core-shell nanoparticles (CSP) were prepared to achieve both reduced friction coefficient and enhanced mechanical properties. Compared with pure photosensitive resin, the 3D printed model with the optimal amount of 2.5 wt% CSP has a lower friction coefficient and wear rate, which are reduced by 77.6 % and 75.8 %, respectively, and the impact strength, tensile strength and elongation at break are increased by 25.7 %, 26.1 % and 40.1 %, respectively. The scratch resistance was evaluated by constant load scratch test and progressive load scratch test. The results showed that CSP significantly improved the scratch resistance of 3D printed models, and the penetration depth was continuously reduced from 175.5 μm to 128.3 μm under a load of 30 N. These findings indicate that CSP is a promising scratch-resistant additive for application, expanding the application range of photocurable 3D printing.