Patent GB-980509-A (GB)
Title: Linear polyether resins and processes for their production
IPC: C08G59/62
Filed: 1961-07-31
Abstract: Linear condensation products having high impact resistance are prepared by heating, in the presence of 0.005 to 0.1 mol of an alkaline catalyst and of a solvent for reactants and products, mixtures containing less than one per cent of water, of 1 mol of a dihydric phenol of formula <FORM:0980509/C3/1> and 0.98 to 1.025 mols of a diglycidyl ether of formula <FORM:0980509/C3/2> wherein R1, R2, R3 and R4 are chosen independently of one another, and consist (if desired together with carbon atoms C1 and C2) of H, alkyl with not more than six carbon atoms, cyclohexyl, phenyl or alkyl substituted cyclohexyl, phenyl, or their halogen derivatives, the total number of carbon atoms in the groups attached to C1 or C2 not exceeding 18. The rings in the starting materials may be substituted, e.g. by alkyl groups or halogen atoms. The catalyst may be an alkali, e.g. sodium or potassium hydroxide, ammonia or benzyltrimethyl ammonium hydroxide or an amine, a sodium or ammonium salt of the dihydric phenol, and any phenol provided by the catalyst as well as any saponifiable chlorine in the diglycidyl ether is taken into account in calculating reactant ratios.  The catalyst is neutralized with carbon dioxide at the end of the reaction.  The solvent must maintain reactants and product in solution at the reaction temperatures and concentrations, must not react significantly with epoxide or phenolic OH groups, must be readily and completely removable from the final reaction mixture and must have a boiling point which permits reaction at 75-150 DEG C. Suitable solvents are methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, mesityl oxide, chloroform, 1,2-dichloroethane, dioxane, tetrahydrofuran, 1,2-dimethoxyethane, methyl or ethyl ethers of ethylene glycol, dimethyl formamide, cyclo tetra methylene sulphone, or suitable mixtures.  The epoxy reagent may be a crude mixture containing at least 70% of the simple diepoxide, the remainder being diglycidyl polyethers of the dihydric phenol of higher molecular weight (see Specification 930,640). It should be free of mono-epoxide and monohydric alcohol or phenol.  The product may be recovered as shreds by pouring a solution of them into a non-solvent, e.g. water, or as sheets by pouring the solution on to the top roll of a two-roll mill to evaporate the solvent.  The products in solution may also be worked up directly to coating compositions.  Many examples are given, mostly concerned with the reaction of p,p1-bisphenol A with its diglycidyl ether, and illustrating small variations in reaction conditions.  When using methyl ethyl ketone as a solvent, it is sometimes advisable to add 1-3% of water to it. In Example 18, 4.4% of the initial phenolic hydroxyl functionality is provided by 2,4-bis-(a ,a  - dimethyl - p - hydroxybenzyl) - phenol.  Other reagents used in the examples are bis-(4 - hydroxylphenyl) methyl phenyl methane; bis - (4 - hydroxyphenyl)methane; 1,1 - bis - (4 - hydroxyphenyl)ethane; 2,2 - bis - (4 - hydroxyphenyl)butane; 2,2 - bis - (4 - hydroxyphenyl)nonadecane; bis - (4 - hydroxyphenyl)-diphenylmethane; bis - (2,3 - epoxy - propoxyphenyl)methyl phenyl methane.  Example 38 describes the reaction of 2, 2-bis-(3,5:dimethyl-4-hydroxyphenyl)propane with epichlorhydrin to produce the diglycidyl ether which is then reacted in sulpholane an equimolar proportion of the same dihydric phenol.  Example 39 is similar, but uses 2,2 - bis - (3,5 - dichloro - 4 - hydroxyphenyl) propane.  The physical and chemical properties of the products of the examples were determined.  Specifications 652,024 and 666,732 are referred to.