construction of fe(iii)/fumarate-based metal-organic framework (mof) grown on graphene oxide (go) nanocomposites as an excellent uv blocker for epoxy coatings (ecs): appearance and surface investigation

The mil-88a (fe) as a fe(iii)/fumarate-based metal-organic framework (mof) was grown on the graphene oxide (go) and a novel hybrid nanocomposite (go-m) was fabricated to improve weathering properties of epoxy coatings by blocking uv rays. the go contribution in hybrid go-m pigment was 13.5 wt.% and the nanoparticles were incorporated in the epoxy coatings ( 0.15 wt.%). some reports indicated go and mil-88a are potent uv absorbers and they can substantially reduce the photodegradation extent. herein, the free epoxy film with go-m hybrid nanocomposite (ec/go-m) showed more absorbance in the uva and uvb region and less transmittance than neat epoxy coating (ec), and the films loaded with go or mil-88a additives separately. the coatings were placed in the quv accelerated weathering tester up to 400 hours and some aesthetic analysis were measured. the ec/go-m sample faced with the least changes of color (de), blueness-yellowness (db), and lightness (dl). the roughness (ra and rz) and hardness (h) of all coatings were increased, but the increments were significantly lower in the coatings containing go-m nanoparticles. also, the water contact angle (ca) measurements demonstrated the ca decrement was fewer than 5% in ec/go-m panel while this value was more than 20% in ec and ec/go coatings. all results confirmed the excellent weathering resistance of epoxy coatings in the presence of go-m hybrid nanocomposites.

Construction of Fe(III)/fumarate-based metal-organic framework (MOF) grown on graphene oxide (GO) nanocomposites as an excellent UV blocker for epoxy coatings (ECs): appearance and surface investigation

The MIL-88A (Fe) as a Fe(III)/fumarate-based metal-organic framework (MOF) was grown on the graphene oxide (GO) and a novel hybrid nanocomposite (GO-M) was fabricated to improve weathering properties of epoxy coatings by blocking UV rays. The GO contribution in hybrid GO-M pigment was 13.5 wt.% and the nanoparticles were incorporated in the epoxy coatings ( 0.15 wt.%). Some reports indicated GO and MIL-88A are potent UV absorbers and they can substantially reduce the photodegradation extent. Herein, the free epoxy film with GO-M hybrid nanocomposite (EC/GO-M) showed more absorbance in the UVA and UVB region and less transmittance than neat epoxy coating (EC), and the films loaded with GO or MIL-88A additives separately. The coatings were placed in the QUV accelerated weathering tester up to 400 hours and some aesthetic analysis were measured. The EC/GO-M sample faced with the least changes of color (dE), blueness-yellowness (db), and lightness (dL). The roughness (Ra and Rz) and hardness (H) of all coatings were increased, but the increments were significantly lower in the coatings containing GO-M nanoparticles. Also, the water contact angle (CA) measurements demonstrated the CA decrement was fewer than 5% in EC/GO-M panel while this value was more than 20% in EC and EC/GO coatings. All results confirmed the excellent weathering resistance of epoxy coatings in the presence of GO-M hybrid nanocomposites.