Alkyd resins modified with

The alkyd resins are of value because of their comparatively low cost, durability, flexibility, gloss retention and reasonable heat resistance. Alkyd resins modified with rosin, phenolic resin, epoxy resins and monomers such as styrene are of current commercial importance. 

The phthalic alkyd class is broken down into resins which are unmodified, resins which are modified, except with rosin and rosin ester, and finally resins which are modified with rosin and rosin ester. Under each class various chemical compositions are broken out for purposes of analysis. The alkyd resins modified with rosin and rosin ester are going to be considered in the rosin ester class of materials rather than the phthalic alkyd class of materials. Figures on phthalic alkyds have been available since 1933 11), The Tariff Commission has used more than one type of breakdown over this period. In 1946 they broke down total alkyds into two classes oil-type alkyds as compared with other than oil-type alkyds. Before and after that year, this breakdown was not made. 

Alkyd resins modified with compounds such as styrene, vinyl toluene, and methyl methacrylate have become more important in... 

PEG polyesters with unsaturated dibasic acids such as maleic acid are used to modify polyester resins for paints so as to improve their elasticity and scratch resistance. Alkyd resins modified with PEGs can be made so hydrophilic that they are dispersible in water [17]. 

Phthalate based polycondensate resins, modified with unsaturated fatty acids and styrene as well as vinyltoluene have many applications in the form of paints and lacquers as alkyd resins". 

Low-molar-mass poly(butadiene) oils with 80%-97% cw-1,4 contents are produced with other Ziegler catalysts (for example, cobalt compounds with alkyl aluminum chlorides or nickel compounds with trialkyl aluminum and boron trifluoride-etherate). The products have few cross-links and dry as fast as wood oil and faster than linseed oil. Conversion of the poly (butadiene) oils with 20% maleic anhydride gives air-drying (air-hardening) alkyd resins. Modified poly (butadiene) oils stabilize erosion-endangered soils. Because of its low viscosity, the aqueous emulsion penetrates the surface soil layers. The surface crust is reinforced by an oxidative bonding process. Since no skin is formed on the soil crust, the aqueous absorption characteristics of the soil are retained. 

Alkyd emulsions are made by dispersing a liquid alkyd resin in water by mechanical means. Alkyds are polyester resins modified with fatty acids. They are produced by reacting fatty acids with a polyol such as glycerol (1,2,3-trihydroxypropane) and a dibasic acid such as orthophthalic acid... 

Alkyd resin n. A polyester resin resulting from the condensation of a polyfunctional alcohol and acid, typically glycerine and phthalic anhydride. Today the term is mostly used for (1) resins modified with drying oils and used as vehicles for varnishes and paints and (2) for cross-linking resins in alkyd molding compounds. The word alkyd is an acronym, from al- for alcohol, and -cid (changed to kyd) for acid. G Alkydharz n, F resine alkyde, resine f, S resina alquidica, resina f, I resina alchidica, resina f. ... 

Precooked tung oil-alkylphenolic resin combinations, chilled with drying oil modified alkyd resins. Dehydrated castor oil (DCO)-modified alkyd resin, pigmented with calcium orthoplumbate (COP) as main pigment in the priming coat. 

Alkyd Synthetic resin modified with oil. Coating that contains alkyd resins in the binder. 

In coatings and adhesives, isocyanates may be used as reactive species at room temperature, or by modification, at high temperatures. Most urethane varnishes, however, are probably solutions of alkyd resins modified by reaction of free hydroxyl groups with diisocyanates. 

The polycondensation of di-isocyanates with polyhydric alcohols gives a wide range of polyurethanes which are used as artificial rubbers and light-weight foams, and have other important properties. Isocyanates are also used as modifiers in alkyd resins. ... 

The properties of the polymers may be modified by mixing abphatic acids or anhydrides with the phthalic anhydride. Many alkyd resins find application in the paint industry. 

Alkyd resins are produced by reaction of a polybasic acid, such as phthaUc or maleic anhydride, with a polyhydric alcohol, such as glycerol, pentaerythritol, or glycol, in the presence of an oil or fatty acid. The resulting polymeric material can be further modified with other polymers and chemicals such as acryhcs, siUcones, and natural oils. On account of the broad selection of various polybasic acids, polyhydric alcohols, oils and fatty acids, and other modifying ingredients, many different types of alkyd resins can be produced that have a wide range of coating properties (see Alkyd resins). 

Substituted heat-reactive resins are most widely used in contact-adhesive appHcations and, to a lesser extent, in coatings (77,78) -butylphenol, cresol, and nonylphenol are most frequendy used. The alkyl group increases compatibiHty with oleoresinous varnishes and alkyds. In combination with these resins, phenoHcs reduce water sensitivity. Common appHcations include baked-on and electrical insulation varnishes, and as modifiers for baking alkyds, rosin, and ester gum systems. Substituted heat-reactive resins are not used for air-dry coatings because of theh soft, tacky nature in the uncured state substituted nonheat-reactive phenoHcs are the modifying resin of choice in this case. 

One of the important attributes of alkyds is their good compatibiUty with a wide variety of other coating polymers. This good compatibiUty comes from the relatively low molecular weight of the alkyds, and the fact that the resin stmcture contains, on the one hand, a relatively polar and aromatic backbone, and, on the other hand, many aUphatic side chains with low polarity. An alkyd resin in a blend with another coating polymer may serve as a modifier for the other film-former, or it may be the principal film-former and the other polymer may serve as the modifier for the alkyd to enhance certain properties. Examples of compatible blends foUow. 

Although blending with other coating resins provides a variety of ways to improve the performance of alkyds, or of the other resins, chemically combining the desired modifier into the alkyd stmcture eliminates compatibiUty problems and gives a more uniform product. Several such chemical modifications of the alkyd resins have gained commercial importance. 

Low viscosity cellulose propionate butyrate esters containing 3—5% butyryl, 40—50% propionyl, and 2—3% hydroxyl groups have excellent compatibihty with oil-modified alkyd resins (qv) and are used in wood furniture coatings (155). Acetate butyrate esters have been used in such varied apphcations as hot-melt adhesive formulations (156), electrostatically spray-coated powders for fusible, non-cratering coatings on metal surfaces (157—159), contact lenses (qv) with improved oxygen permeabiUty and excellent wear characteristics (160—162), and as reverse-osmosis membranes for desalination of water (163). 

Alkyds. Alkyd resins (qv) are polyesters formed by the reaction of polybasic acids, unsaturated fatty acids, and polyhydric alcohols (see Alcohols, POLYHYDRic). Modified alkyds are made when epoxy, sUicone, urethane, or vinyl resins take part in this reaction. The resins cross-link by reaction with oxygen in the air, and carboxylate salts of cobalt, chromium, manganese, zinc, or zirconium are included in the formulation to catalyze drying. 

Silicone alkyds These are alkyds modified with silicone resin. They have superior resistance to weathering (particularly gloss retention) than pure alkyds but are generally significantly more expensive. They are useful for exterior use where appearance is important. 

The typical alkyd resin (see above) is eomprised of three basic components an aromatic diacid such as phthalic anhydride which together with a polyol such as glycerol, forms the backbone of the resin molecule and along which are distributed the fatty acids derived from vegetable oils. The solubility, film hardness and colour of alkyd resins depend on the nature of the modifying fatty acid which in most cases contributes some colour to the film. 

Saturated polyesters and saturated alkyds cannot undergo such modification with vinyl monomers but can be modified with other polymers such as silicone resins by alcoholysis. Here outdoor durability is considerably improved. 

These are the most important components of paint. Coatings can be either clear or opaque (containing pigments) and either solvent- or water-based. With solvent-based paints, after application, most of the solvent is lost through evaporation. These solvent-based coatings are mostly alkyds (name derived from alkyl/acid) or modified alkyd resins. Normally they contain 30% polymer solids higher solids content is limited by the increasing viscosity of the system. 

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