Pvdf Fluorine Resin Coating Composition And Performance

In this paper the effect of component part and preparation and application process on polyvinylidene difluoride (PVDF) coatings was studied, the results provided the basis for PVDF coatings ratio and preparation technology design.Some problems often affect the performance of PVDF coatings, for example coating thixotropy increasing, coating cosmetic defects, unstable weatherability, burnish fluctuations, etc. By studying the miscibility of the solvent and PVDF resin, acrylic resin and PVDF resin, temperature change during the preparation, cooling in different ways, comparing pigment weathering, the mechanism related factors had been identified.It was found that PVDF resin dispersion is the low-viscosity when the ketone and ester as dispersing medium by comparing viscosity and thixotropy of various solvent dispersions. PVDF dispersion to isophorone as a dispersing medium receives lower viscosity and smaller thixotropy, which is more conducive to PVDF coatings roller application.Acrylic resin composition in PVDF coatings was studied. According to competition theory of hydrogen bonding the PVDF resin/acrylic resin mixture viscosity fluctuations were analyzed and discussed. Experiments showed that the compatibility impact of the PVDF resin depend on acrylic resin composition. With the increasing content of hydrogen bond donors in the acrylic resin structure, the miscibility of Acrylic resin/PVDF dispersion was decreased. PMMA resin is the best material compatibility. While adding other strong hydrogen bond donors, the hydrogen bonds between PVDF resin and acrylic resin will be destroyed, so that the viscosity and thixotropy was increased dramatically.Weathering of some pigments in PVDF coatings was researched by artificially accelerated aging test. Pigment volume concentration, hiding power, and light resistance can cause poor weatherability.The coating performance influenced by cooling method after the baking process was studied. PVDF resin cooled at different rates has different crystal. The PVDF coatings cooled by water that mainly contains the Crystalβhas a high gloss and cooled by air that mainly contains the Crystal a has a low gloss. The two kinds of Crystal also caused the difference in gloss retention. Comparing a variety of temperature the viscosity of dispersion was found paint rheological behavior mutation when the temperature is higher than 70℃, the viscosity increased rapidly, affecting the coating properties of PVDF coatings.By studying the solvents, resins, pigments., preparation temperature and cooling method, the mechanism of various factors was summed up, which can adjust the coating formulation and process design to improve the coating performance and the application performance of PVDF coatings.