Exterior formulations

TROYSAN CMP has demonstrated efficacy against a broad range of fungal organisms. However, because of its water solubility, it is not recommended for use in exterior formulations without test fence exposure. TROYSAN CMP may be used in water-based formulations only. 

TROYSAN PMA-30 Can be used as an in-can preservative as well as a mildeweide for exterior formulations. 

Acrylates are primarily used to prepare emulsion and solution polymers. The emulsion polymerization process provides high yields of polymers in a form suitable for a variety of appHcations. Acrylate polymer emulsions were first used as coatings for leather in the eady 1930s and have found wide utiHty as coatings, finishes, and binders for leather, textiles, and paper. Acrylate emulsions are used in the preparation of both interior and exterior paints, door poHshes, and adhesives. Solution polymers of acrylates, frequentiy with minor concentrations of other monomers, are employed in the preparation of industrial coatings. Polymers of acryHc acid can be used as superabsorbents in disposable diapers, as well as in formulation of superior, reduced-phosphate-level detergents. 

Binders and Resins. The choice of binder is the most important ingredient choice in the formulation process because the binder affects the performance properties of a paint more than any other single ingredient (3). The physical properties of binders required for paints include the abiHty to dry or cure under various ambient conditions, good adhesion to various substrates, abrasion resistance, washabiHty, flexibiHty, water resistance, and ultraviolet light resistance. The balance of these required properties is mosdy dependent on whether the paint is being developed for interior or exterior appHcations. 

PyCis usuaHy expressed in percentage, but the % sign is often omitted. Although many additives in the paint formulation are nonvolatile, they are often omitted from this calculation, because they represent a smaH fraction of the volume of a newly formed paint film and, in exterior paints, are often water-soluble materials leached out by rainfaH, and therefore wHl probably not factor into the long-term performance of the paint film. 

A third criterion for the proper formulation of house paints is volume soHds level. Paint with low volume soHds are characterized by poor adhesion and poor exterior durabiUty. A low volume soHds paint film does not have the tensile strength properties necessary for good adhesion found in a higher volume soHds paint (10). Also, any slight dismption or imperfection in the dried paint film or in the appHcation of a low volume soHds paint can result in poor durabiHty properties. 

Developments in the 1980s and 1990s include phosphoric acid-based formulations for the cleaning of exterior automotive plastic parts and the demand for high purity electronics-grade phosphoric acid. 

Unsaturated polyester resin powders can provide a colored and finished exterior molded surface or a finish ready for painting. Normally, a primer/sealer must be appHed to molded articles prior to painting. In addition to the unsaturated polyester resin, multifimctional unsaturated monomers such as triaHyl cyanurate (TAC) [101-37-1] or diaHyl phthalate (DAP) [131-17-9] suitable peroxide initiators (qv) or mixtures thereof, and mold release agents (qv) are used to formulate the coating powder (46). 

Color Properties Required. Colorants must be chosen to permit formulation of a coating that can meet performance requirements such as exterior durability and resistance to solvents, chemicals, and heat. Health and safety regulations may also affect colorant choice. 

There are limitations to the appHcabiHty of exterior latex house paints providing a small continuing market for oil or alkyd exterior house paints. Because film formation from latex paints occurs by coalescence, there is a temperature limit, below which the paint should not be appHed. This temperature can be varied by choice of the T of the latex polymer and the amount of coalesciag agent ia the formula. Ia the United States, most latex paints are formulated for appHcation at temperatures above 5—7°C. If painting must be done when the temperature is below 5—7°C, oil or alkyd paint is preferable. 

Nylon 11 Nylon 11 is a hard abrasion-resistant, scuff-resistant coating. When correctly formulated and applied, it can be used for exterior application. It has good resistance to solvents and to a range of alkalis and salt solutions up to 80°C. If water quenched, the coating has excellent impact strength. However, Nylon 11 is crystalline and pull-back from sharp edges can be a problem. It is therefore essential that metal work is well radiused. 

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