Alkyd resins design

An aromatic compound which is employed along with glycerol in the production of alkyd resins is phthalic anhydride. The conventional process for the manufacture of this chemical has been from the catalytic oxidation of coal tar naphthalene, and annual production of the anhydride in recent years has been around 150,000,000 pounds. In 1946 production was started (4) in a plant of the Oronite Chemical Co. at Richmond, Calif., to produce phthalic anhydride by the oxidation of o-xylene produced in a hydroformer unit of the adjacent Standard Oil Co. of California refinery. The Oronite plant was reported to have a design capacity of 7,000,000 to 8,000,000 pounds per year of 99.7% pure phthalic anhydride. 

A complete renge of colors designed for oil-phase print systems containing alkyd resins as binding agents. 

Classification and Properties of Alkyd Resins Formulation and Design of Alkyd Resins Uses of Alkyd Resins Saturated Reactive Polyesters Resin Systems for Reduced Solvent Emissions Low-Solvent and Solvent-Free Alkyd Resins... 

The coreaction of phenolic resins with alkyds is an "old timer" in which the excellent gloss retention and durability of alkyds are combined with the water and alkali resistance of phenolics. Alkyd resin can be designed to have compatibility with hydroxyl-modified vinyl chloride-vinyl acetate copolymer resins, and this combination of fast drying, adhesion, excellent water resistance, and durability is specified in a number of coatings for military and marine use. 

The relatively low molecular weights of alkyd resins allow medium-high solids at brushing viscosity (about 5 poises). Films dry to touch in about 1-4 hours in warm weather, but take longer when it is cold. Once air is allowed into the paint can, drying occurs at the surface forming a skin it does not usually go deeper. Alkyd films harden slowly over many days. Those designed to last outdoors are soft and easily marked, but very flexible. 

The effects of film thickness on the drying of alkyd resin-based paints can be directly monitored by ratioing the intensity of the carbonyl band at 1735 cm against the alkene stretch band at 1636 cm h To avoid saturation of the strong carbonyl band, a 60° ZnSe crystal was used. The cured resin was readily cleaned from the trough with either methylene chloride or acetone. The unique out-of-compartment design permits the use of UV lamps or other radiation sources to evaluate their effects on rate of cure. 

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