Alkyd resins vinyl monomers

A common procedure for the preparation of vinylated alkyds is as foUows. A base alkyd resin is brought to the desired endpoint. The resin is then cooled to about 160°C and often diluted with aromatic thinner. The desired monomer is added, usually at about 20 —60% based on the final product, foUowed by an appropriate amount of a free radical initiator. Alternatively, a premix of the monomer and the initiator is added at a controUed rate over most of the reaction. The reaction is brought to monomer reflux, until the residual monomer content has fallen below a specified level. Residual monomer, if any, is stripped away before the product is diluted in a solvent, filtered, and packaged. 

Glycidyl and Vinyl Esters. Glycidyl neodecanoate [26761-45-5] sold commercially as GLYDEXXN-10 (Exxon) or as CarduraElO (Shell), is prepared by the reaction of neodecanoic acid and epichl orohydrin under alkaline conditions, followed by purification. Physical properties of the commercially available material are given in Table 3. The material is a mobile Hquid monomer with a mild odor and is used primarily in coatings. Eor example, it is used as an intermediate for the production of a range of alkyd resins (qv) and acryHcs, and as a reactive diluent for epoxy resins (qv). 

Saturated polyesters and saturated alkyds cannot undergo such modification with vinyl monomers but can be modified with other polymers such as silicone resins by alcoholysis. Here outdoor durability is considerably improved. 

Several other resins can be blended with alkyd resins to introduce desired improvement in properties, e. g. cellulose nitrate, chlorinated rubber, phenolics, amino resins or silicons oils. Vinyl monomers like styrene can be added to alkyd resins along with initiator to get a tougher resin with shorter drying times and lighter colour. 

The manufacturing of alkyd resins involves a wide variety of organic ingredients. Whereas most of them are relatively mild and of low toxicity, some, such as phthalic anhydride, maleic anhydride, solvents, and many of the vinyl (especially acrylic) monomers, are known irritants or skin sensitizers and are poisonous to humans. The hazard potential of the chemicals should be determined by consulting the Material Safety Data Sheets provided by the suppliers, and recommended safety precautions in handling the materials should be practiced. 

Alkyd resins have been the workhorse for the coatings industry over the last half century. The term alkyd was coined to define the reaction product of polyhydric alcohols and polybasic acids, in other words, polyesters. However, its definition has been narrowed to include only those polyesters containing monobasic acids, usually long-chain fatty acids. Thus thermoplastic polyesters typified by polyethylene terephthalate (PET) used in synthetic fibers, films, and plastics and unsaturated polyesters typified by the condensation product of glycols and unsaturated dibasic acids (which are widely used in conjunction with vinylic monomers in making sheet molding compounds or other thermosetting molded plastics) are not considered as part of the alkyd family and are beyond the scope of the present discussion. 

One major use of polyesters, the alkyd coating resins, is based on random prepolymers reacted with unsaturated fatty acids. Gelation phenomena have been studied extensively and the gelation theories of Carothers, Flory, and Stock-mayer were developed with polyester random prepolymers. Only recently, Gordon (iJ, 12) has extended the gelation theory to the structopendant polyester system cross-linked by vinyl monomers. 

Chem. Descrip. Vinyloxazoline diester of an unsat. fatty acid Uses Monomer for polymerization, improving pigment wetting and resin props, (adhesion to metal, weathering, corrosion resist.), for use in alkyd resins, acrylic/vinyl resins, car repair/primer systems gloss aid for acrylic topcoats applied on SER-AD FX 521 modified alkyd primers Properties Gardner 11 max. clear liq. dens. 940 kg/m (20 C) vise. 275 mPa s (20 C) acid no. 10 max. flash pt. > 100 C 100% act. 

First comes the unsaturated polyester resin itself. From Chapters 12 and 15 we should have a clear idea of what is meant by a polyester resin and, in particular, a saturated polyester resin. Although a drying-oil alkyd is, in a sense, an unsaturated polyester resin, the term has come to be applied solely to polyester resins based on components which introduce unsaturation directly into the polyester backbone. This unsaturation must be capable of direct addition copolymerization with vinyl monomers. To give a linear polymer, any of the dibasic acids or dihydric alcohols mentioned in Chapters 12 and 15 may be used, but the resin should include some unsaturated components. These are usually, though not necessarily, acids, e.g. ... 

Polyester Resin—Thermosetting resins produced by dissolving unsaturated, generally linear, alkyd resins in a vinyl type monomer such as styrene and capable of being crosslinked by vinyl polymerisation using initiators and promoters. 

Contact resin n. A liquid resin that thickens or cross-links on heating and, when used for bonding laminates, requires little or no pressure. Typical components are an unsaturated monomer such as an allyl ester, or a mixture of styrene or other vinyl monomer with an unsaturated polyester or alkyd. 

Research on the copolymerization of terpenoids with industrially used vinyl monomers or other monomers have been often reported. Littmann" introduced terpene-maleic anhydride resins for industrial use in alkyd resins in 1936. The resin was synthesized from a-terpinene and maleic anhydride via... 

Emulsions resulting from the emulsion polymerisation of acrylic or vinyl monomers are unique compared to other resins used for surface coating applications. As such they have properties which are totally different to a conventional solution acrylic, polyester or alkyd resins. Their mechanism of film formation is totally different to other types of resins. Because particles are present it is necessary for them to coalesce to film form and pigmentation is also different to conventional solution polymers. Consider first the unique properties and test methods of emulsion polymers. 

Crosslinkers generally used to cure and modify the properties of alkyd/polyester resins include amino resins, phenolic resins, polyisocyanates, epoxy resins, silicone resins and vinyl monomers. In this section, the curing mechanism with amino resins and vinyl monomers will be mainly discussed. Also, the importance and influence of such curing reactions on paint performance will be briefly summarized. However, no attempt will be made here to review the structural influence of basic components in the resins on paint performance. This has recently been comprehensively reviewed. ... 

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