Thermoplastic acrylic resins are the high molecular, physically curing film forming agents. These resins set by giving off solvents, without undergoing a chemical change during film formation. They offered significantly improved color, color stability and exterior durability over other polymers of similar cost. Thermoplastic acrylics are prepared by the polymerization of acrylic monomers and are usually regarded as inert. The major characteristics of thermoplastic acrylics which govern their use in specific applications are: • Color (water white) •Color stability •Chemical & water resistance •Rapid drying •Adhesion •Burn without ash •Exterior durability
Continuing development in the field of acrylic polymers for surface coating applications lead to commercialization of heat curing thermosetting acrylic resins for using in high quality industrial coating systems for both interior and exterior applications. Whilst retaining the excellent color and chemical resistance properties. Thermoset acrylic resins also offer the advantages of significantly higher applications solids, improved hardness and chemical resistance. Furthermore, through judicious choice of backbone monomers, monomer levels and crosslink density, a wide spectrum of film performances can be achieved. As a result thermosetting acrylics started to replace alkyd-amino stoving finishes in automotive and domestic appliances, metal decorating, coil coating and number of other applications.
These resins are based on methacrylate monomers which are used for cold plastic marking paints. They are hard, durable, weather resistant and also resistant to some chemicals such as road salts and fuels. The binder contains paraffin which tends to float when stored for a long period of time at lower temperatures. Therefore, it must be homogenized before use by stirring. Tacryl RM965 is the main binder and Tacryl AC100 is used as an activator, which should be added to the paint right before application. This system will be hardened by adding dibenzoil peroxide and it is used for marking pedestrian crossings, stop lines, direction arrows and safety markings with increased night visibility. It’s suitable for manual application with smoothing trowels or draw boxes. Cold plastic materials are usually applied to asphalt and concrete surfaces in layer thickness of 1.5-2.5 mm. The system is totally solvent free so the thickness of wet and dried film is nearly the same. The reaction will be ended after 30 minutes and the coating will be ready to use.
Two component isocyanate cure acrylics can be attributed to two main factors. The first is the urethane linkage which is formed at ambient temperature by the reaction between the acrylic polyol and the isocyanate pre polymers. The urethane linkage is extremely resistant to chemical degradation by acids, alkalis, petrol, oil and detergents. As the result making coatings based on this technology, is highly suitable for use in aggressive environment. The second attributes is the formulatory flexibility of the hydroxyl functional acrylic. When reacted with the isocyanate component, they produce coatings, which display a blend of following performance characteristics: •Ambient, low bake (60-80) cure •Exceptional chemical resistance •Water white coating •High gloss •Durability •Mechanical properties •Hardness and flexibility These performances attributes have contributed to the important role that the two pack acrylic isocyanate coatings play in the wide range of end user applications, such as: Marin paints, industrial finishing, automotive paint and clear coating refinishes, military applications, masonry coating, vehicle refinishing, aircraft coating, transport finishes and floor coatings.