Investigating the thermo-mechanical and UV-shielding properties of a nano-porous Zr(IV)-type metal-organic framework (MOF) incorporated epoxy composite coating

In the present work, the effects of UIO-66 nanoparticles on the epoxy-polyamide composite coating thermal resistance, mechanical features, and weathering (UV) resistance were explored. The nanoporous UIO-66 particles were developed by the common solvothermal procedure. The final particles were identified by Brunauer-Emmett-Teller (BET), Fourier transform infrared (FT-IR) spectroscopy, and Raman analysis. Also, the thermal properties, as well as the mechanical characteristics of the epoxy nanocomposites loaded with 0.2, 0.4, 0.8, and 1.2 wt% of the UIO-66 particles were studied by thermal gravimetric analysis (TGA), tensile, and dynamic mechanical thermal analysis (DMTA) methods. Besides, the UIO-66 particles containing composite coatings UV resistance at various loadings were studied after 500 h exposure to UV-A irradiation (320-400 nm range) via spectrophotometer analysis, contact angle test, surface roughness analysis, and micro-hardness investigation. BET surface area analysis illustrated a surface area (SA) of 820 m2 g-1 for the constructed metal-organic framework (MOF) particles. TGA outcome exhibited that the temperature related to the weight loss of 80% in the presence of nanoparticles (NPs) increased up to approximately 60 degrees C. On the other hand, the tensile analysis outcomes indicated that the toughness and strain values related to the breaking of the film increased about 2.1 and 1.5 times (at 1.2 wt% filler loading), in comparison with the pure (un-filled) epoxy matrix, respectively. The DMTA test outcomes demonstrated significant improvements of the UIO-66 particles loaded epoxy coatings storage modulus in the glassy region (especially at 1.2 wt%) and crosslinking density (especially at 0.8 wt%). Results proved that the thermal and mechanical characteristics of the nanocomposite were promisingly improved compared to the pure epoxy. Results proved significant epoxy film UV-shielding properties enhancement in the presence of 1.2 wt% UIO particles.

Automated summary

The effects of UIO-66 nanoparticles on the thermal resistance, mechanical features, and UV resistance of epoxy-polyamide composite coatings were investigated. The results showed promising improvements in thermal and mechanical properties, as well as significant enhancement of UV-shielding properties with the presence of UIO-66 particles.