Carbonate, epoxy ester coatings

Epoxidized soybean oil does not form coatings at 185 C for several hours. Obviously, its epoxy groups do not polymerize under these conditions. Both triolein and vernonia oil form good coatings. These results show that vernonia oil drying is based on its unsaturated carbon-carbon double bonds and not on its epoxy functionality. This allows its application as a reactive diluent, not only in epoxy and epoxy-ester formulations, but in alkyd resins as well. 

The role of the triphenylphosphine is similar in the rubber-modification reaction. In this case however the betaine abstracts a proton from the carboxylic acid. The carboxylate anion attacks the electrophilic carbon attached to the phosphorus forming an ester linkage and regenerating the catalyst. The rubber is terminated on both ends by epoxides and can later be crosslinked into the epoxy matrix during the coating and curing phases. This sequence is shown in Reaction Scheme 5. 

Solvents used for paint removal are able to dissolve or considerably swell physically drying binders (e.g., vinyl chloride copolymers, cellulose nitrate, polyacrylates) and chemically cross-linked coatings (e.g., oil-based paints, dried alkyd resins, cross-linked polyester-melamine resins, cross-linked epoxy and isocyanate coatings) [14.237]. A combination of dichloromethane with low-boiling ketones or esters is particularly suitable. Small amounts of high-boiling solvents with a low volatility (e.g., tetrahydronaphthalene, solvent naphtha, methyl benzyl alcohol, or benzyl alcohol) are added to these mixtures to retard evaporation and increase the solvency. Modern paint removers do not contain chlorinated hydrocarbons, they are formulated on the basis of high boilers (e.g., dimethylformamide, dimethyl sulfoxide, propylene carbonate, and yV-methylpyrrolidone) in combination with alcohols and aromatics, or consist of aqueous, frequently alkaline or acidic systems. 

This technique has found the following applications in addition to those discussed in Sections 10.1 (resin cure studies on phenol urethane compositions) [65], 12.2 (photopolymer studies [66-68]), and 13.3 (phase transitions in PE) [66], Chapter 15 (viscoelastic and rheological properties), and Section 16.4 (heat deflection temperatures) epoxy resin-amine system [67], cured acrylate-terminated unsaturated copolymers [68], PE and PP foam [69], ethylene-propylene-diene terpolymers [70], natural rubbers [71, 72], polyester-based clear coat resins [73], polyvinyl esters and unsaturated polyester resins [74], polyimide-clay nanocomposites [75], polyether sulfone-styrene-acrylonitrile, PS-polymethyl methacrylate (PMMA) blends and PS-polytetrafluoroethylene PMMA copolymers [76], cyanate ester resin-carbon fibre composites [77], polycyanate epoxy resins [78], and styrenic copolymers [79]. 

Reinforced Dielectric Materials. Copper-clad dielectrics for HDI can be reinforced, as in FR-4, or unreinforced, as in coated copper foil. The dielectrics can be epoxy, as in FR-4, or polyimide, cyanate ester, bismalene-triazine (BT), PPE, or PTFE. Reinforcements are typicdly glass cloth, but there are a variety of glass as well as aramid paper and exotic fibers such as quartz or carbon fiber. 

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