Polyurethane Resins, cured polyester

FIGURE 18.8 SEM pictures of methylsilica capsules doped with free-radical initiator BPO. These capsules, with a size between 700 and 900 nm, are leach-proof curing agents for polyurethane foams and polyester resins. (Reproduced from Ciriminna, R. et al., ACS Sustainable Chem. Eng., 1, 2013, 1572 with kind permission.)... 

An oil modified polyester resin is mixed with isocyanate, producing a polyurethane resin, which hardens slowly. The curing of the mould is accelerated by a catalyst and completed by heating to 150 T. 

Uses Carboxylated comonomer for polyacrylic and polymethacrylic acids, other acrylic acids, acrylic polymers, styrene-butadiene, vinyl acetate, nitrile latex comonomer for radiation-cured polyester/polyurethane resin paints antimigrant for pigment pad dyeing pigment print emulsifier... 

Uses Defoamerfor solv.-based coatings, esp. wood finishes based on nitrocellulose, acid curing, polyester, or polyurethane, epoxy coatings, chlorinated mbber, or vinyl resin systems, and inks... 

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). 

As it had been shown that silanes were effective as pretreatments for a variety of coatings and particularly so when used as additives, selected silanes were examined as pretreatments and additives in conjunction with a two pack polyamide cured epoxide adhesive (Epikote 828/Versamid 115, 1/1) and a structural polyurethane adhesive based on diphenylmethanediisocyanate and a polyester resin. 

Lucite positive relief structures. Epofix was selected as the chip substrate, among acrylic-polyester resin (Casolite) and epoxy resin (Araldite), because of its having the best mechanical properties and the least chemical interference needed for fabricating the MS chip [780]. In another report, PDMS was chosen over epoxy to fabricate MS chips because of its less chemical noises (interferents) in MS, and over polyurethane because of good adhesion properties. Even so, in the use of PDMS its curing (at 70°C) should be carried out for at least 72 h to further reduce the chemical noise [800]. 

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. 

Although epoxies dominate the thermoset fracture literature, work has been reported on other systems, e.g., polyester resins, phenol-formaldehyde compounds, peroxide cured polystyrene, and highly crosslinked polyurethanes. In general, these materials exhibit fracture behaviors similar to epoxies, and suggest that thermosets, as a class of materials, display characteristic crack growth properties. 

The electron beam curing of coatings has for some time attracted a great deal of attention since It Is claimed that coatings can be fully cured In a fraction of a — second. The coatings are primarily based on the cross-linking of acrylic or epoxy resins In a polyurethane or polyester base (l.e., modified paints). 

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

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