Patent GB-677429-A (GB)
Title: Improvements in the preparation of modified alkyd resins
IPC: C08G63/46
Filed: 1949-05-26
Abstract: Modified alkyd resins are prepared by heating with an organic dibasic acid or anhydride and a polyhydric alcohol the reaction product of ketene and an unsaturated aldehyde of formula R1-CR2=CR3-CHO prepared in the presence of a Friedel-Craft or activated clay catalyst; R1, R2 and R3 being hydrogen or monovalent aliphatic, alicyclic, aryl or aralkyl groups.  Specified aldehydes are acrolein, crotonaldehyde, 2,4-hexadienal-1, octatrienal and cinnamic aldehyde.  In examples the ketene/aldehyde reaction product (hereinafter referred to as the "polymer") is prepared by reacting equimolecular parts of ketene and crotonaldehyde in presence of boron trifluoride and methyl-butyl ether as solvent (see Group IV (b)).  (1) The "polymer," dissolved in isopropyl ether, is heated with phthalic anhydride and linseed monoglyceride.  Glycerol and then xylene are added, the mixture refluxed with addition of xylene, water is removed from the reflux, and the product thinned with xylene and butanol.  (3) A "polymer"-modified oil is prepared by refluxing a mixture of the "polymer," linseed oil, glycerol, calcium naphthenate and xylene. The modified oil is then heated with glycerol and calcium naphthenate, phthalic acid and xylene added and the mixture refluxed with water separation.  (4) Pentaerythritol is added to a preheated mixture of soya oil and calcium naphthenate, the mixture heated and phthalic anhydride and the "polymer" dissolved in diethyl ether added.  Further pentaerythritol is added, xylene added and the mixture refluxed.  The product was thinned with xylene and butanol. (5) A mixture of the "polymer" dissolved in isopropyl ether, adipic acid, linseed monoglyceride, glycerol and xylene are refluxed and the product dissolved in xylene and butanol.  (6) The "polymer" dissolved in xylene, adipic acid and glycerol are warmed together, sulphuric acid in methanol added, the mixture refluxed and the product thinned with toluene.  (7) Maleic anhydride, linseed fatty acids and 1 : 2 : 3-trimethylol propane are heated, the "polymer" dissolved in isopropyl ether added, toluene added, the mixture refluxed and the batch thinned with xylene.  (8) Dehydrated castor oil and calcium naphthenate are heated, glycerol added, the mixture heated and the "polymer" dissolved in xylene, D 4-3,6-endomethylene tetrahydrophthalic anhydride (cyclopentadiene-maleic adduct) and ethylene glycol added, the mixture refluxed and the product thinned with xylene.  Instead of the alcohols exemplified arabitol, mannitol or sorbitol may be used.  Specifications 570,839, 677,428 and U.S.A. Specification 2,421,976 are referred to.ALSO:Polymeric esters are prepared by reacting an unsaturated aldehyde of formula R1-CR2= CR3-CHO (where R1, R2 and R3 are hydrogen or monovalent aliphatic, alicyclic, aryl or aralkyl groups) and ketene at low temperatures and in presence of a Friedel-Crafts or activated clay catalyst. Specified aldehydes are acrolein; crotonaldehyde; 2,4-hexadienol-1; octatrienal; and cinnamic aldehyde.  In an example ketene and crotonaldehyde are reacted in presence of boron trifluoride and methyl-butyl ether at 5-10 DEG  C. to yield a monomer unit of formula <FORM:0677429/IV (b)/1> This polymerizes by addition to yield polymeric esters of 3-hydroxy-hex-4-en-1-oic acid and 4- or 5-hydroxy-hex-2-en-1-oic acids.  Hydrogenation of the reaction product yielded about 80 per cent of the six carbon acids; caproic, delta caprolacetone, trans-hexen-2-oic and other products.  The reaction product is used to modify alkyd resins (see Group IV (a)). Specifications 570,839, 677,428, [Group IV (a)], and U.S.A. Specification 2,421,976 are referred to.