Alkyd resins condensation polymerization

The formation of alkyd resins is a typical example of condensation polymerization. In 1847, Berzelius reported a resinous product formed by the reaction of tartaric acid and glycerol. In 1901, Watson Smith (England) prepared a brittle resinous polymer by... 

Alkyd resins are based on polymeric resins developed in the 1920s. The first alkyd resins sold commercially under the name Glyptal were made by the General Electric Company (Fig. 3.20). Alkyd resins are a class of polyesters synthesized by condensation between an alcohol and an acid or anhydride. Actually, the anhydride is modified with a monofunctional acid, most commonly C g fatty acid, which can be obtained from vegetable oil (rubber seed oil (RSO) or palm oil) [61-63]. The major advantage of the alkyd resins is their components (fatty acids and triglyceride... 

Polymeric ipa-b- mer-ik, polymerism pa- li-mo- ri-zom n, ad]. (1) Substance, the molecules of which consist of one or more structural units repeated any number of times vinyl resins are examples of true polymers. The name is also frequently applied to large molecules produced by any chemical process, e.g., condensation in which water or other products are produced alkyd resins are examples of these. Homopolymer - Polymer of which the molecules consist of one kind of structural unit repeated any number of times polyvinyl chloride and polyvinyl acetate are... 

The condensation of an alcohol with an acid to give an ester with water as a by-product is a classical way to make polymers (Table 17.1,1). In alkyd resin cooking (Section 13.4), it was mentioned that additional reactions are those between anhydride and alcohol or epoxide and between free acid and alcohol and esters (transesterification). The simple polyester with its repeating dyadic structure can be dissolved in styrene (about 70 parts polyester to 30 parts styrene) and polymerized at room temperature by a free-radical route using a redox couple. (Methyl ethyl ketone peroxide plus cobalt naphthenate would be typical.) Glass-reinforced boat hulls and automobile bodies are made from such systems. In some cases, monomers more expensive than styrene can be justified. Methyl methacrylate, triallyl cyan-urate, and diallyl phthalate have been suggested by various sources. Flammability... 

Covalent polymeric networks which are completely disordered. Continuity of structure is provided by an irregular three-dimensional network of covalent links, some of which are crosslinks. The network is uninterrupted and has an infinite molecular weight. Examples are vulcanized rubbers, condensation polymers, vinyl-divinyl copolymers, alkyd and phenolic resins. 

Formaldehyde polymerizes by condensation with phenol and urea to form phenol— and urea— formaldehyde resins which are popular and inexpensive adhesives. They are paint and coatings often used in coatings when combined with alkyds, epoxides, polyesters, or acrylic to give strong flexible films. 

Castor oil fatty acids have one double bond per molecule, whereas hydrogenated castor oil fatty acids are saturated consequently, the oils, or alkyds derived from them, are not film forming under autooxidation conditions. However, alkyds prepared from these oils are widely used as polymeric plasticizers for other filmforming resins the two most important types are cellulose nitrate and melamine-formaldehyde condensates. 

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