Polyester coating systems

Polymers. The molecular weights of polymers used in high energy electron radiation-curable coating systems are ca 1,000—25,000 and the polymers usually contain acryUc, methacrylic, or fumaric vinyl unsaturation along or attached to the polymer backbone (4,48). Aromatic or aUphatic diisocyanates react with glycols or alcohol-terrninated polyether or polyester to form either isocyanate or hydroxyl functional polyurethane intermediates. The isocyanate functional polyurethane intermediates react with hydroxyl functional polyurethane and with acryUc or methacrylic acids to form reactive p olyurethanes. 

Another specialty area is coil coating, which involves coating metal coils by continuous operation. Modern roller systems afford speeds of up to 200 m/min. Most coils are made of cold-rolled and surface treated steel, aluminum, or alloys of the latter with manganese or magnesium. Coating systems are based on alkyd or acrylic resins, oil-free polyester, silicone-modified polyester or acrylic resin, poly(vinylidene fluoride), or poly(vinyl fluoride). Water-reducible systems, mainly based on acrylic resins, have been developed for aluminum as well as for steel coils [21-24], Drying is carried out by continuous operation in gas- or oil-heated multichamber ovens. 

This isoindoline nickel complex pigment is mainly recommended for the coloration of metallics and effect coatings, especially for water based systems. P.R.271 affords yellowish to medium red shades, providing a bright flop in metallics. Alkyd/melamine resin systems may safely be overcoated and withstand exposure of 140°C for 30 minutes. The flow properties of P.R.271 in these systems and in polyester cellulose acetobutyrate base coat systems are good, but there is a certain tendency to flocculate. 

From an industrial point of view, not only the high-molecular-weight linear polyesters are of interest. Also, a series of low-molecular-weight linear or branched polyesters (Example 4-1) find application in surface coating systems (alkyd resins), as coreactants in unsaturated polyester resins (Example 4-8), or in polyurethane foams (Examples 5-28 and 5-29). 

D. Schmaljohan, B.I. Voit, J.F.G.A. Jansen, P. Hendrdriks, J.A. Loontjens, New Coating Systems Based on Vinyl Ether- and Oxetane-modified Hyperbranched Polyester, Macromol. Mater. Eng. 275,31-41 (2000)... 

Conventional industrial coatings materials of the thermoset type are usually acrylic, polyester, epoxy, polyurethane or silicone resins dispersed or dissolved in organic or water/ether-alcohol coupling solvents. They are cured with gas convection or electric IR ovens. The raw materials for the polymers come from petroleum feedstocks which are processed or manufactured into a finished coating system. 

The nonacrylic monomer styrene is used as a reactive solvent in the polymerisation of coating systems on the basis of unsaturated polyesters. Styrene has a penetrating and unpleasant odour and a strong irritant effect. In spite of this substitute, products such as 2-phenyl-l-propene (a-methylstyrene), n-vinylpyrrolidone and vinyltoluene have not become established owing to their clearly inferior application properties. 

Chemical produces methylamine and its derivatives, and acrylic, polyurethane and polyester rapid cure and pressure-sensitive resins for solvent-free coating systems ... 

Miscellaneous Extrusion-Applied Polymers. As mentioned earlier, there is a tendency to develop solventless magnet wire enamel formulations, and extrudable polymer systems would fulfill that requirement. There have been reports about extrusion of thin coatings of polyesters over copper wire. At this point, the state of the art allows extrusion of thin insulating films only with thermoplastic materials. The reliable extrusion of uniform and concentric insulating films of approximately 0.001-0.002 in. wall thickness is already an improvement over the more traditional extrusions of polyethylene, poly(vinyl chloride), and several fluoropolymers in much greater wall thicknesses. Because cross-linked insulation is ultimately required for most magnet wire applications, further materials development needs to be done to provide polymer compositions that are both extrudable as thin films and can be cross-linked in an economical process suitable for large-scale industrial application. 

The earliest commercial urethane coatings were based on polyester-polyisocyanate systems that exhibited excellent abrasion resistance, toughness, and a wide range of mechanical strength properties. Most urethane coating systems in this country were first based on tolylene diisocyanate (TDI), while in Europe many systems based on 4,4 -methylene bis(phenyl isocyanate) (MDI) were developed. In order to avoid the use of free TDI, adducts of polyols such as trimethyolpropane or 1,2,6-hexanetriol with TDI were introduced, particularly for two-component coatings (1., 2). 

Lnpraphcn. [BASF AG] Polyester poly for die prod, ci ptdyurethane, dwmioplastic grmules, textfie coating systems, finished parts made of polyurethane and casting elastomers for foe auKunotive, machine and equfo. construction industries. 

SiUkoftal . [Tego] Silicone-modified polyester resin binders for high gloss coatings, one-coat systems, decorated... 

Lupraphen. [BASF AG] Polyester pol> for the juod. of polyur ane, thermt lastic grmules, textile coating systems, finisl parts made of polyurethane and casting elasbuners for the aummotive, machine and equip, con-structkm Industries. 

When polymerization is used as the hardening principle, reactive components combine to form the binder, e.g., unsaturated polyesters with styrene or acrylate monomers. Here, one component often behaves as a reactive solvent for the other, and low-emission coating systems are the result. Cross-linking can be carried out at room temperature (cold curing) or by radiation curing. 

It is however, with the more complex and comprehensive investigation of ternary systems that this molecular mechanics approach started to yield results of greater interest on the fundamental principles of adhesion [32]. Ternary systems present two interfaces because they are composed of three molecular species, namely the cellulose substrate, a photopolymerizable primer resin, and a top coat alkyd/polyester varnish [32]. This work was started mainly to address the concept of flexibility of a surface finish system on lignocellulosic materials but led to some unexpected and rewarding results on adhesion too. Examples of the visualization of the conformations of minimum energy of ternary systems are shown in Figs. 4-6. 

The systems can include many options surfiice veil, chopped liners, sprayed resin systems, hoop winding strands, helical winding strands, resin bath, unidirectional tape, woven roving tape, pigmented resin surfaces, wax-resin surfaces, gel coats, BPO catalyst, epoxy resins, vinyl ester resins, filled resin systems, abrasive resin systems, polyester foam, syntactic foam, and charting film. 

Chem. Descrip. Acrylate coploymer, absorbed on silicone dioxide Uses In powd. coating systems based on epoxy, acrylate, polyester, and polyurethane... 

Uses Crosslinking agent in melamine resin coating systems, general industrial finishes, coil-coating enamels, appliance finishes, useful with alkyd, polyester, thermosetting acrylic, epoxy, and cellulose resins Properties Gardner 2 max. clear, vise, liq. limited water-sol. dens. 10.0 Ib/gal vise. (G-H) X-Z2 flash pt. > 180 F 98% NV Cymel 350 [Cytecind.j... 

Chem. Descrip. 3-Methaciyloxypropyl trimethoxysilane CAS 2530-85-0 EINECS/ELINCS 219-785-8 Uses Coupling agent for free-radical crosslinked polyester, rubber, polyolefins, styrenics, acrylics adhesion promoter for solv., water-based, solventless, arid powd. coating systems pigment treatment Properties Sp.gr. 1.040 vise. 2 cSt flash pt. (CC) 46 C 100% act. 

Chem. Descrip. Linear high m.w. sat. polyester resin Uses Polyester for coil coating primers and one-coat systems, laminate adhesives, deep-drawable, stamping enamels for can coatings Properties Sp.gr. 1.23 (20 C) acid no. < 3 hyd. no. 9 100% solids Dynapol L 490 [Degussa AG/Coatings Colorants]... 

Chem. Descrip. Linear low m.w. sat. polyester resin in aromatic soivs. Uses Polyester for coil coatings, top coats, spray coatings and one-coat systems for exterior applies. 

Uses Defoamer for soiv.-borne, polyurethane, and acid-curing coatings, unsat. polyester systems, and NC lacquers Properties SI. yish. clear Iiq. dens. 0.86-0.89 g/cm (20 C) flash pt. 25 C ... 

Uses Texturizer, slip agent, abrasion resist, aid for powd. coatings based on hybrid systems, polyesters, urethanes Features Stable inc. matted appearance improves metal mark resist, scratch resist. aids in dirt removal from coat surfs. 

Uses Matting agent, mar resist, aid, scratch resist, aid for solvent-borne and waterborne coatings, esp. wood coatings, varnishes, plastic coatings, and stoving enamels based on acrylics, acid-catalyzed systems, polyesters, two-pack PU, acrylic and PU disps., NC and blends Features Smooth, soft surf, feel esp. rec. in clearcoats where minimal haze is required... 

Uses Surfactant, emulsifier, pigment wetting agent/dispersant, color acceptance agent for industrial coating systems, esp. latex paints, and for solvent-borne architectural paints, printing inks, adhesives, latexes food pkg. adhesives defoamer in food-contact paper coatings Features Low-foam remedies defoamer-induced film defects suitable for PVAc, acrylics, S/B, PVC/PVdC, alkyds, HC resins, NC, PU, epoxy, polyesters... 

Chem. Descrip. y-Methacryloxypropyltrimethoxysilane CAS 2530-85-0 EINECS/ELINCS 219-785-8 Uses Adhesion promoter for adhesives and coatings coupling agent for glass-reinforced and min.-filled thermosetting resins blend additive in resin systems (polyester, acrylic), and filled or reinforced thermoplastic polymers (polyolefins, polyurethanes)... 

Uses Flow aid, leveling agent for p. coatings for polyesters, epo) resin systems, epoxy esters, crosslinking acrylics, polyurethanes Features Silicone-free Properties Powd. 

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