Polyester finishes resins

Unsaturated polyester finishes of this type do not need to be stoved to effect crosslinking, but will cure at room temperature once a suitable peroxide initiator cobalt salt activator are added. The system then has a finite pot life and needs to be applied soon after mixing. Such a system is an example of a two-pack system. That is the finish is supplied in two packages to be mixed shortly before use, with obvious limitations. However, polymerisation can also be induced by ultra violet radiation or electron beam exposure when polymerisation occurs almost instantaneously. These techniques are used widely in packaging, particularly cans, for which many other unsaturated polymers, such as unsaturated acrylic resins have been devised. 

Application To produce polyesters for resin and textile applications from terephthalic acid (PTA) or dimethyl terephthalate (DMT) and diols [ethylene glycol (EG) or others], using the UIF-proprietary four-reactor(4R)-process including DISCAGE-finisher. 

FDA 1998 regulates BP as an indirect food additive. It is permitted as a catalyst not exceeding 2% of the finished resin, and as an optional adjuvant in the production of cross-linked polyester resins intended for repeated use in contact with food 21CFR177.2420. EPA Reportable Quantity lOlbs. For MEK Peroxide ACGIH TLV (ceiling) 0.2 ppm (1.5 mg/m3) and OSHA PEL (ceiling) of 0.7 ppm (5 mg/m3). 

Polyester-styrene resins have a low raw material price and are used in wood finishing. Disadvantages are the presence of volatile styrene and the low cure speed. Products with methacrylic groups are used where line (cure) speed is less important, mainly in combination with acrylates in special end uses (e.g., in the electronics industry and in photopolymer printing plates) to improve adhesion or to obtain specific physical properties. Thiol- thiene mixtures can lead to very flexible cured films but their odor seriously limits their use. 

Chem. Descrip. Fatty acid-modified polyester PU resin (45%) in water/N-methyl pyrrolidone, neutralized with dimethyl ethanolamine Uses Polyester for highly flexible aq. stoving systems, e.g., stone chip-resist. primer surfacers for on-line automotive finishing Features Rec. in combination with water-thinnable amino resins Properties Ylsh./brnsh. cloudy appearance 45 015 nm mean particle size sol. in water, alcohols, glycols, glycol ethers dens. = 1.1 ml (20 C) vise. 200-2000 mPa-s-(23 C) add no. 13 02 pH 7.25 00.75 (1 3 in DW) equiv. wt. = 1417 anionic 4501%NV Bayhydrol PR 135 [Bayer AG]... 

Chem. Descrip. Hexabutoxymethyl melamine resin Uses Crosslinking agent for alkyd/polyester or acrylic resins, tor use in solv.-borne coatings, acid curing wood finishes, resinous/polymeric food-contact coatings... 

Polyester finishes contain polyester resins, which, in turn, contain predominantly ester linkages. Polyurethane finishes need not contain polyurethane resins and the urethane linkage is not necessarily predominant in the dry paint film. However, all polyurethane finishes contain isocyanates or their reaction products, so the reader should be familiar with isocyanate reactions before proceeding further with this chapter. 

Adhesives based on methyl methacrylate and epoxy resins are used by engine-fitter mechanics (Castelain et al. 1992). In this way, they can come into contact with DGEBA, TGPAP, TGMDA, and epoxy novolac. Painters can work with products containing cyclohexanone peroxide, a catalyst for polyester finish. The standard allergens to consider are listed in Table 2 additional allergens in the aircraft industry are listed in Table 3. 

A variety of thermosetting resins are used in SMC. Polyesters represent the most volume and are available in systems that provide low shrinkage and low surface profile by means of special additives. Class A automotive surface requirements have resulted in the development of sophisticated systems that commercially produce auto body panels that can be taken direcdy from the mold and processed through standard automotive painting systems, without additional surface finishing. Vinyl ester and epoxy resins (qv) are also used in SMC for more stmcturaHy demanding appHcations. 

The sulfur dyes are widely used in piece dyeing of traditionally woven cotton goods such as drill and corduroy fabrics (see Textiles). The ceUulosic portion of polyester—cotton and polyester—viscose blends is dyed with sulfur dyes. Their fastness matches that of the disperse dyes on the polyester portion, especiaUy when it is taken into account that these fabrics are generaUy given a resin finish. 

Carpet. Carpet, an important textile, may also be treated to provide water and oU repeUency however, the principal functions of the current carpet treatments are to provide soU and stain resistance. High quaUty carpets, especiaUy those made from nylon, polyester, or wool, have a significant proportion of the surface coated with fluorochemical materials. The treatments can be spray-appUed to a finished carpet or appUed directly to the fiber during the spinning or dyeing operations. Suitable fluorinated resin materials are readily avaUable from 3M or DuPont. 

Some commercial durable antistatic finishes have been Hsted in Table 3 (98). Early patents suggest that amino resins (qv) can impart both antisHp and antistatic properties to nylon, acryUc, and polyester fabrics. CycHc polyurethanes, water-soluble amine salts cross-linked with styrene, and water-soluble amine salts of sulfonated polystyrene have been claimed to confer durable antistatic protection. Later patents included dibydroxyethyl sulfone [2580-77-0] hydroxyalkylated cellulose or starch, poly(vinyl alcohol) [9002-86-2] cross-linked with dimethylolethylene urea, chlorotria2ine derivatives, and epoxy-based products. Other patents claim the use of various acryUc polymers and copolymers. Essentially, durable antistats are polyelectrolytes, and the majority of usehil products involve variations of cross-linked polyamines containing polyethoxy segments (92,99—101). 

The principle of blending a conduction fiber with a static-prone fiber has been known for years. A mixture of a substantial quantity (30—40%) of a hydrophilic fiber such as cotton or rayon with a hydrophobic static-prone fiber such as a polyester can produce a static-free blend under ordinary conditions. However, blocking the hydrophilic groups by cross-linking of the cotton with biflinctional reagents such as dimethylolethylene urea or addition of a water-repellent finish such as a sUicone resin increases the static propensity of such a blend. 

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). 

Acryflc coating powders have achieved some success in Japan utilizing resins having gflcydyl methylacrylate functionality cured with C q—0 2 dicarboxyflc acids (49). Hybrid polyester—acryflc coating powders have also been reported in which an acid functional polyester resin coreacts with a glycidyl-containing acryflc polymer (50). Hydroxyl functional acryflc resins cured with blocked isocyanates have also been available for many years in the United States and achieved some commercial success as appliance finishes. 

Phenohc resins (qv), once a popular matrix material for composite materials, have in recent years been superseded by polyesters and epoxies. Nevertheless, phenohc resins stiU find considerable use in appHcations where high temperature stabiHty and fire resistance are of paramount importance. Typical examples of the use of phenoHc resins in the marine industry include internal bulkheads, decks, and certain finishings. The curing process involves significant production of water, often resulting in the formation of voids within the volume of the material. Further, the fact that phenoHcs are prone to absorb water in humid or aqueous conditions somewhat limits their widespread appHcation. PhenoHc resins are also used as the adhesive in plywood, and phenohc molding compounds have wide use in household appliances and in the automotive, aerospace, and electrical industries (12). 

The resins are also used for coating on to moulds to give a good finish that is to be used for polyester hand-lay up operations. 

These requirements are usually met with two-pack paints based on hydroxyl-rich polyester or acrylic resins in the pigmented pack and aliphatic polyisocyanates in the activator pack. Cure with this type of finish is relatively fast and complete even at low ambient temperatures. An alternative finish is an acrylic lacquer, similar to the lacquer used for refinishing motor cars. These finishes are applied to the assembled aircraft by operators protected by air-fed hoods and using airless or conventional spray guns. High durability pigments are included. 

Good quality steel is used and electrozinc is preferred for washing machines. Steel is pretreated with iron phosphate for economy electrozinc with a fine crystal zinc phosphate. No primer is normally used 25-40/im of finish is applied direct to metal. The required properties are best obtained with a thermosetting acrylic or polyester/melamine-formaldehyde finish. Self-reactive acrylics are usually preferred these resins contain about 15 Vo 7V-butoxymethyl acrylamide (CH2=CH —CO —NH —CHj—O —C4H,) monomer and cure in a manner similar to butylated melamine-formaldehyde resins. Resistance or anti-corrosive properties may be upgraded by the inclusion of small amounts of epoxy resin. Application is usually by electrostatic spray application from disc or bell. Shapes are complex enough to require convected hot-air curing. Schedules of 20 min at 150-175°C are... 

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). 

Aromatic amines formed from the reduction of azo colorants in toy products were analysed by means of HPLC-PDA [703], Drews et al. [704] have applied HPLC/ELSD and UV/VIS detection for quantifying SFE and ASE extracts of butyl stearate finish on various commercial yarns. From the calibrated ELSD response the total extract (finish and polyester trimer) is obtained and from the UV/VIS response the trimer only. Representative SFE-ELSD/UV finish analysis data compare satisfactorily to their corresponding SFE gravimetric weight recovery results. GC, HPLC and SEC are also used for characterisation of low-MW compounds (e.g. curing agents, plasticisers, by-products of curing reactions) in epoxy resin adhesives. 

It has been shown that xanthan gum is an effective migration inhibitor for the application of water-soluble chemicals, leading to uniform distribution and more reproducible fixation [379]. Although this work was specifically concerned with the application of a soluble flame retardant to polyester, suitability for the application of reactive dyes or resin finishes is also claimed. 

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