Polymer resins and varnishes
What are polymer resins?
The resins are named after the reactions leading to their production: polymerization, polycondensation and polyaddition. Thus, polymer resins are produced by the polymerization method. In this chemical reaction, small monomers bind into macromolecules (giant particles) by breaking double bonds.
What important binders belong to the polymer resins?
The main group of polymer resins are acrylic resins. Other important polymer resins are dispersion paint binders: polyvinyl acetate, vinyl polypropionate, styrene-butadiene copolymer, ethyl polyacylate, polymethacrylate. Polymer resins used as lacquer binders are equally important. These include PVC copolymers (polyvinyl chloride), polychloroprene and chlorosulfonated polyethylene.
Please list important properties of polymer varnishes
Most polymer varnishes dry physically by the evaporation of solvents and thinners. Coatings made of these varnishes harden, keeping the thermoplastic character (reversible) and therefore show no particular resistance to solvents.
Two-component polymer varnishes, e.g. two-component acrylic varnishes, however, they cure irreversibly and are very resistant to solvents.
The chemical resistance of polymer varnishes is sufficient for most applications. Thus, most polymer resins are alkali-resistant and non-saponifiable. Varnishes made of these resins are resistant to weather conditions.
The mechanical strength of physically drying varnishes and paints is not very high. On the other hand, two-component polymer varnishes are very scratch-resistant.