Oil alkyd

More frequentiy, alkyd resias are described by a combiaed classification ia terms of thek oil length, the type of fatty acids, and any unusual kigredients. Such descriptions as an isophthaUc, very long tall oil alkyd a medium oil dehydrated castor-PE ( pentaerythritol, not polyethylene) alkyd or a short oil lauric-ben2oic alkyd, immediately project the general properties of the reski. 

Nitrocellulose based lacquers often contain short or medium oil alkyds to improve flexibiUty and adhesion. The most commonly used are short oil non drying alkyds. Amino resins or urethane resins with residual isocyanate functional groups may be added to cross-link the coating film for improved solvent and chemical resistance. The principal appHcations are furniture coatings, top lacquer for printed paper, and automotive refinishing primers. 

Silicone resins with high phenyl contents may be used with medium or short oil alkyds as blends in air-dried or baked coatings to improve heat or weather resistance the alkyd component contributes to adhesion and flexibiUty. AppHcations include insulation varnishes, heat-resistant paints, and marine coatings. 

The specific solvents that make up the three solvency categories depend on the solute in question. For example, an aUphatic hydrocarbon may have adequate solvency for a long oil alkyd, but would be a diluent for an acryUc or vinyl resin, which require stronger solvents such as ketones or esters. The formulator must understand the solvency requirements of the solute to know which category a particular solvent would occupy. 

Trimethylolpropane (TMP), the reduced crossed aldol condensation product of //-butyraldehyde and formaldehyde, competes in many of the same markets as glycerol (qv) and pentaerythritol. The largest market for TMP is as a precursor in unsaturated polyester resins, short-oil alkyds, and urethanes for surface coatings (see Alkyd resins). 

Another approach to high soHds alkyd coatings is the partial replacement of solvent in a conventional long-oil alkyd with a reactive diluent. Eor example, dicyclopentenyloxyethyl methacrylate [70191-60-9J, mixed amides from the condensation of acrylamide (qv) (2-propeneamide)... 

Short-oil alkyd Hard Fair Fair Poor Fair Good Fair Easy... 

Long-oil alkyd Flexible Fair Poor Poor Poor Good Good Easy... 

With these lacquers, nitrocellulose-based primer-surfacers are used. As well as liquid plasticisers, a wide range of materials are used as plasticising resins short oil alkyds, maleinised oils, ester gum, rosin and bodied castor oils. Pigmentation is usually inert. Thermoplastic acrylics are often preferred under acrylic lacquers these are based on acrylic resins and cellulose acetate butyrate. 

Coating materials may be based on short or medium-oil alkyds (e.g. primers for door and window frames) nitrocellulose or thermoplastic acrylics (e.g. lacquers for paper or furniture finishes) amino resin-alkyd coatings, with or without nitrocellulose inclusions, but with a strong acid catalyst to promote low temperature cure (furniture finishes) two-pack polyurethanes (furniture, flat boards) unsaturated polyester resins in styrene with free-radical cure initiated by peroxides (furniture) or unsaturated acrylic oligomers and monomers cured by u.v. radiation or electron beams (coatings for record sleeves paperback covers, knock-down furniture or flush interior doors). 

Medium lanthanides, 74 631 Medium oil alkyds, 2 148 Medium performance sealants, 22 28 Medium pH, for fermentation, 77 38 Medium-temperature radiation furnaces, 72 292-293... 

Short-fiber composites fabrication of, 26 766 Short fiber metal-matrix composites, casting process for, 76 168 Short fiber web layering systems, 77 504 Short oil alkyds, 2.T48 Short random fiber reinforcement,... 

Fig. 72 Pigment Orange 34 samples of different particle sizes (above small, below large) in a long-oil alkyd resin system. Pigment concentration in the system 6% thickness of the wet film 75 pm.

Fig. 77 P. 0.34 in a long-oil alkyd resin system. Influence of the particle size on the dispersibility. Dispersion unit paint shaker, organic pigment Ti02 = l 5. Sample 1 fine particle pigment,...

Fig. 81 Scanning electron micrographs of long-oil alkyd resin systems containing P.R.3, (a) nonhazing, (b) hazing. Drying time 1 day.

Conditions to be met in oven drying enamels depend also on the composition of the binder. Paint systems containing melamine-formaldehyde or urea-formaldehyde resins, for instance, harden by polycondensation with other resins, such as epoxy resins, short-oil alkyd or acrylic resins at elevated temperatures. Baking is carried out at temperatures between 100 and almost 200°C and may last from a few minutes to more than an horn. A general trend towards energy conservation has shifted public attention towards binders which require low baking temperatures. 

P.R.ll has largely been replaced by other products. Its hue is a bluish red which resembles the color of ruby P.R.ll is more bluish than its positional isomer P.R.7. Both pigments behave similarly as far as fastness properties are concerned, which includes fastness to most of the solvents that are used in paints and printing inks, fastness to overlacquering, heat stability, and others. However, P.R.ll is much less lightfast than P.R.7 incorporated in medium-oil alkyd systems at 1/3 SD, P.R.ll scores 2 steps less on the Blue Scale (step 4). 

P.O.19 has stimulated only limited industrial interest and is rarely used in Europe. It provides a shade which in white reductions resembles that of P.O.34, but which is much duller. Its full shade is noticeably yellower than that of P.O.34. P.O.19, incorporated in medium-oil alkyd resin systems, is less lightfast, both in full shade and in white reductions, than opaque P.O.34 types. The commercially available type exhibits poor rheological behavior. 

Rapeseed oil - [ALKYD RESINS] (Vol 2) -feedstocks for fatty acids [CARBOXYLIC ACIDS - MANUFACTURE] (Vol 5) -m hydraulicfluids [HYDRAULIC FLUIDS] (Vol 13) -use m dairy substitutes [DAIRY SUBSTITUTES] (Vol 7)... 

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