Patent GB-650436-A (GB)
Title: Improvements in or relating to polyesters of 2-ethylhexanediol-1:3 and their use as plasticisers
IPC: C08K5/10
Filed: 1948-04-29
Abstract: Liquid polyesters having a molecular weight of at least 500 are made by reacting 2-ethyl-hexanediol-1 : 3 with an aliphatic saturated dicarboxylic acid having from 4 to 10 carbon atoms or an anhydride of such acid, the molar ratio of the diol to the acid or anhydride being between 1.01 and 1.5.  Part of the diol may be replaced by a polyethylene glycol.  As a modification, any residual hydroxyl groups in the polyester are acylated with a fatty acid anhydride.  The products are useful as plasticizers for vinyl resins and cellulose derivatives.  Suitable dibasic acids are succinic, adipic, 3,31-thio-dipropionic or sebacic acids.  The amount of glycol which may replace diol is between 1 in 5 and 1 in 2, depending on the chain length of the dibasic acid.  A table shows the products to be compatible with cellulose nitrate, polymethylmethacrylate resin, polyvinyl acetate and chloride and their copolymers, and chlorinated rubber; slightly incompatible with cellulose acetate-butyrate and in some cases ethyl cellulose, and incompatible with cellulose acetate, polystyrene, and polyvinyl butyral.  The polyesters are preferably made by heating the reactants in the presence of a solvent which forms an azeotrope with water, to facilitate its removal.  An example describes reacting together: (1) succinic anhydride, 2-ethyl-hexanediol-1 : 3, and benzene, by refluxing for 16 hours, adding a sulphuric acid catalyst and refluxing a further 16 hours, while distilling off water.  The product after stripping in a falling film still is a liquid of molecular weight 666.  The product is then reacted with an excess of 2-ethyl hexanoic anhydride by heating at 150 DEG  C. for 4 1/2 days.  Other examples describe similar procedure employing as reactants with the diol (2) and (3) succinic acid and acetic anhydride or 2-ethylhexanoic anhydride; (5) adipic acid, and acetic anhydride; (7) sebacic acid and acetic anhydride; (8) 3,31-thio-dipropionic acid and acetic anhydride; (9) succinic, adipic, or mixtures of succinic and adipic, or succinic and sebacic acids in different proportions, and acetic anhydride. A table gives the properties of a vinyl copolymer plasticized by the products. Example 10 describes the reaction of mixtures of the 2-ethyl-hexane-diol-1,3- and 1,10-decane-diol, tri-ethylene glycol, tetra-ethylene glycol with succinic acid, and a mixture of the diol and tri-ethylene glycol with adipic acid.  The products are acetylated and used to plasticize a vinyl copolymer, a table of physical properties being given.  Other examples describe compositions of (4), a polyester as in (3) and vinyl chloride-vinyl acetate copolymer, with (A) lead silicate, mineral oil, calcium carbonate, red iron oxide, carbon black, and red and brown pigments; (B) calcium stearate, dibutyl tin laurate-maleate, and aluminium hydrate; (C) dibutyl tin laurate-maleate and stearic acid; (D) they may be used as a backing for pressure-sensitive tape.  A composition for electrical insulation comprises the polyester of (5), a vinyl chloride/acetate copolymer, lead silicate, lead stearate, and clay.