Crosslinked Polyesters

High-resolution 13C NMR studies have been conducted on intact cuticles from limes, suberized cell walls from potatoes, and insoluble residues that remain after chemical depolymerization treatments of these materials. Identification and quantitation of the major functional moieties in cutin and suberin have been accomplished with cross-polarization magic-angle spinning as well as direct polarization methods. Evidence for polyester crosslinks and details of the interactions among polyester, wax, and cell-wall components have come from a variety of spin-relaxation measurements. Structural models for these protective plant biopolymers have been evaluated in light of the NMR results. 

Other common binders include nitrocellulose (acetone as the solvent), polyvinyl alcohol (used with water), and Laminae (an unsaturated polyester crosslinked with styrene — the material is a liquid until cured by catalyst, heat, or both, and no solvent is required). Epoxy binders can also be used in hquid form during the mixing process and then allowed to cure to leave a final, rigid product. 

Hyperbranched polyester crosslinked photorefractive polymers were prepared by Nishikata [4] consisting of Dispersant Red-19, (VII), and trimesic acid or trimesic acid containing isophthalic acid. Perfluorobenzoate Dispersant Red-19 derivatives, (VIII), were also prepared by the author [5]. 

IR-ATR and ESCA spectroscopy have been applied to the study of photo-oxidation and photostabilization of unsaturated polyesters crosslinked with styrene. Results obtained show that both styrene and polyester units of the cured resins are vulnerable to UV oxidative degradation and are easily photo-oxidized. 

This vinyl ether is monomeric in character and is used as a chemical intermediate or os o crosslinking ogent. Addition of isocyanic acid produces secondary diisocyonates. Divinyl ethers hydrolyze to the glycol and acetaldehyde. Chlorine or bromine odd to the double bonds. Reaction with an alcohol in the presence of water produces a diacetal. Polymerization of divinyl ether of diethylene glycol with acidic catolysts produce crasslinked gels. Unsoturoted polyesters, crosslinked with styrene, hove been made noncorrosive to metols through use of divinyl ethers to reduce hydroxyl ond acid numbeis. 

Figure 6.18 Production of an (ortho) unsaturated polyester crosslinked matrix...

Figure 8.20 Typical reaction scheme of side chain LC polyester crosslinking using diisocyanate.

Polyesters Crosslinkers, cocuring resins Industrial coatings... 

The structure of unsaturated polyester crosslinking with vinyl monomers, such as styrene, may be described in the simplest form as short polystyrene units linked by double bonds at different polyester molecules, as follows ... 

Polyester crosslinker Masonry Floor, textiles Emulsions for textiles Floor polishes Photographic films Milk Carton... 

Polyester crosslinker Polypropylene Japan 6,795 1968 Chisso Corp. ... 

MA chain transfer, 244, 253 MA monomer, 239, 243-253, 259 Radical polymerization initiators, for polyester crosslinking, 487-491 Raman spectroscopy, MA spectrum, 8 Raney nickel hydrogenation catalyst, 42 7-Rays, polymerization initiation, 239-241,... 

MA copolymerization, 332 MA modified, 479, 500 polyester crosslinkers, 490, 500 synthesis, 500 Vinyl ethers alkyl... 

Curing of oil-modified alkyds with polyisocyanates results in faster drying, better chemical resistance and abrasion resistance. Hydroxylated polyesters crosslinked with both aromatic and aliphatic polyisocyanates are finding extensive applications in high-quality maintenance finishes. These two-component finishes cure at ambient temperature. Aliphatic urethane types are used on aircraft, rail and other transportation equipment where excellent gloss retention and... 

The product, in the case of R = butyl, dibutyltin ddaurate (DBTDL), can also be made from the oxide, as in Reaction (31). DBTDL is a stabilizer of only modest effee-tiveness and is now rarely used in PVC. It is, however, a strong esterifieation/ hydrolysis eatalyst, and finds much use in preparation of polyesters, crosslinking of polyurethanes, and in hydrolysis of silanes (previously grafted to polyolefins) to provide sdoxane crosslinks. Much more effective stabilizers result from reaction wifli maleic acid ... 

The primer/surfacer, composed most often of a polyester crosslinked with a blocked isocyanate or MF resin, is generally appUed at a dty film thickness of approximately 25 microns (1.0 ml) by conventional spray application equipment. The primer is often made conductive through the incorporation of conductive pigments such as carbon black, to increase the transfer efficiency of the electrostatic topcoating process. 

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