Phenol-aldehyde resins

Phenolic resins were the first totally synthetic plastics invented. They were commercialized by 1910 [I]. Their history begins before the development of the structural theory of chemistry and even before Kekule had his famous dreams of snakes biting their tails. It commences with Gerhardt s 1853 observations of insoluble resin formation while dehydrating sodium salicylate [2]. These were followed by similar reports on the behavior of salicylic acid derivatives under a variety of reaction conditions by Schroder et al. (1869), Baeyer (1872), Velden (1877), Doebner (1896 and 1898), Speyer (1897) and Baekeland (1909-1912) [3-17]. Many of these early reports appear to involve the formation of phenolic polyesters rather than the phenol-aldehyde resins that we think of today. For... 

Phenolic-aldehydic resin that remains permanently thermoplastic unless methylene groups are added. 

A blend of a polyoxyalkylene-polysiloxane copolymer and an alkoxy-lated phenol-aldehyde resin is useful as a demulsifier [1457, 1458]. 

Resols are phenolic aldehyde resins that undergo self-cross-linking catalyzed with bases or basic salts. Their structure depends on the choice and molar ratios of the raw materials (e.g., phenols and cresols), the solvents, and the type and amount of catalyst used. Resols have free hydroxymethyl groups which can react on heating to form homocondensates. Heterocondensation with other reaction partners is also possible. 

Novalak—A phenolic-aldehydic resin that, unless a source of methylene groups is added, remains permanently thermoplastic. 

Novolac (novolak) According to ASTM D 883, a novolac is a phenolic-aldehyde resin, which, unless a source of methylene groups is added, remains permanently thermoplastic. For a preferred definition, see phenolic novolac. However, the term is also used in connection with epoxies. Lenz RW (1967) Organic chemistry of synthetic high polymers. Interscience Publishers Inc., New York. 

Phenol-aldehyde polymers n. Common name for phenol, polymer with formaldehyde. It is also commonly known as phenol-aldehyde resin. 

A phenol-aldehyde resin containing reactive phenolic hydroxyl groups, plus an epoxide resin. After heat curing, high degrees of tensile, shear, and peel strengths were obtained. 

Blending phenol-aldehyde resins with poly(vinyl butyral crotonal) or other poly(vinyl acetals) [133]. 

Chen C M 1980 Phenol-aldehyde resin composition containing pecan pith extract and an aldehyde. U S Pat No 4201699... 

The cyclic phenol-formaldehyde resins were naturally produced in low yield as by-products of linear resins [17[. In the cyclic phenol—aldehyde resin, the end valences are joined to form a cyclic structure, for example. 

Other factors of importance in these reactions will be brought out in the foUoTiving pages. For a detailed study of phenol-aldehyde resins, the reader is referred to "The Chemistry of Synthetic Besins" by Carleton EUis. ... 

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