Acryloyl-group functionalized graphene
In a new study scientists prepared acryloyl-group functionalized graphene to enhance thermal and mechanical properties of acrylated epoxidized soybean oil UV-curable based coatings.
To reinforce AESO-based UV-curable coatings, acryloyl-group functionalized graphene (acr-RGO) was successfully prepared and characterized using attenuated total reflection-Fourier transformed infrared spectroscopy, X-ray diffraction, Raman spectroscopy, and thermogravimetric analysis.
The AESO/acr-RGO nanocomposite coatings were fabricated using UV-curing technology to covalently introduce graphene sheets into the AESO matrix. Real-time infrared and ATR-FTIR spectroscopy were used to monitor double-bond conversions and deep curing in the AESO/acr-RGO coating. Scanning electron microscope images revealed the homogeneous dispersion of acr-RGO in AESO. The thermal and mechanical properties of cured films were evaluated through thermogravimetric analysis, tensile testing, and dynamic mechanical analysis.
Enhancing the coating properties
The results revealed that the introduction of acr-RGO effectively enhanced the mechanical properties and the thermal stability of the host resin AESO. The optimal reinforcing effect was observed at 1.0 wt% acr-RGO loading, under which the tensile strength and storage modulus of the AESO/acr-RGO nanocomposite improved by 167% and 15%, respectively, compared with those of neat AESO. The initial degradation temperature of the AESO/acr-RGO nanocomposite was also sharply improved by 61 °C under a loading of 0.5 wt%. Additionally, a slight increase in the glass transition temperature of the AESO/acr-RGO nanocomposite from 29.6 to 36.1 °C was observed when acr-RGO was incorporated.
Furthermore, introducing acr-RGO enhanced the coating properties. By contrast, the composite coating using amino-group functionalized graphene (AESO/ami-RGO) nanocomposites exhibited poorer mechanical properties and lower thermal stability than its acr-RGO counterpart. The remarkable property reinforcements are thus attributed to the acryloyl-group functionalization of graphene, which improved the compatibility and enhanced the interfacial adhesion of graphene with the AESO matrix.
The study is published in: Progress in Organic Coatings Volume 118, May 2018, Pages 57-65.
Image source: Pixabay
