Patent GB-723777-A (GB)
Title: New polymeric substances
Inventor: FARTHING ALAN CHARLES
IPC: C08G65/18
Filed: 1951-08-22
Abstract: Polymers of oxacyclobutanes of the formula <FORM:0723777/IV (a)/1> where X and Y = halogen, cyanide, hydroxyl, alkoxy, aroxy or acyloxy or may be joined to form a ring with oxygen as the heterocyclic element are produced by contacting the monomers preferably in the absence of water with a Friedel-Crafts catalyst, e.g. BF3 or its complexes, sulphuric acid, stannic chloride, aluminium chloride, gallium trichloride or a tertiary oxonium salt, e.g. triethyl oxonium fluoborate, e.g. at a temperature between -80 DEG  C. and 150 DEG  C. The temperature may be controlled by a low-boiling solvent, e.g. methyl chloride, sulphur dioxide or monofluorodichloromethane. Polymers are linear or cross-linked.  The monomers are prepared from pentaerythritol or its derivatives, e.g. the 1,3-chlor- or brom-hydrin.  A suitable monomer is <FORM:0723777/IV (a)/2> or 2,6-dioxaspiro-(3,3)heptane.  It yields a hard, insoluble, cross-linked product.  Co-polymers may be made.  Where X and Y in the above formula are both OH they may be protected by preliminary condensation with acetone and regenerated after the polymerization. The products may be moulded, cast into films or made into fibres. Examples describe (1), (2) and (3) polymerization of 3,3-bis chloromethyl oxacyclobutane with boron trifluoride diethyl etherate. Removal of unchanged monomer gives a harder product; (4) polymerization with boron trifluoride of 3-chloromethyl-3-acetoxymethyl-oxacyclobutane or of 3,3-bis-acetoxymethyl - oxacyclobutane; (5) polymerization of 3-hydroxymethyl-3-chloromethyl-oxacyclobutane with boron trifluoride etherate; (6) isopropylidene-3,3-bis-hydroxymethyl-oxacyclobutane treated with boron trifluoride etherate gives a polymer with a repeating unit <FORM:0723777/IV (a)/3> Treatment with water, followed by hydrochloric acid, splits off acetone to yield a polymer with the repeating unit <FORM:0723777/IV (a)/4> (7) 3,3-bis-chloromethyl-oxacyclobutane is polymerized with boron trifluoride at 0 DEG  C. in monofluorodichlormethane; (8) a copolymer of 3,3-bis-chloromethyl-oxacyclobutane and isopropylidene - 3,3 - bis - hydroxymethyl - oxa - cyclobutane is prepared.  It is sticky and soluble in ethanol until treated with dilute hydrochloric acid; (9) is similar to (7); (10) 3,3-bis-ethoxymethyl-oxacyclobutane is polymerized with boron trifluoride etherate; (11) 3,3-bis-phenoxymethyl-oxacyclobutane is polymerized with boron trifluoride etherate.  The products may be used for moulding or for making films, sheets, fibres or yarns.ALSO:Oxacyclobutanes of the general formula <FORM:0723777/IV (b)/1> where X and Y are halogen, cyanide, hydroxyl, alkoxy, aroxy, or acyloxy or are joined to form a ring with oxygen as the heterocyclic element are obtained from derivatives of pentaerythritol.  In examples: (4) 3,3-bis-chloromethyl oxacyclobutane heated with potassium acetate yields 3-chloromethyl-3-acetoxymethyl-oxacyclobutane (B.Pt. 120 DEG C. at 13 mms.) and 3,3-bis-acetoxymethyl oxacyclobutane (B.P. 152 DEG C. at 21 mms); (5) pentaerythritol dichloride heated with caustic potash in ethyl alcohol yields 3-hydroxymethyl-3-chloromethyl oxacyclobutane; (6) pentaerythritol monochloride (obtained by hydrolysis of 3 - hydroxymethyl - 3 - chloromethyloxacyclobutane with H2SO4) is treated in acetone with dry HCl, neutralized with K2CO3, filtered, washed and distilled to yield isopropylidene pentaerythritol monochloride <FORM:0723777/IV (b)/2> (B.P. 130-140 DEG  C. at 9 mms.).  Treatment of this product with potassium hydroxide is ethyl alcohol yields isopropylidene-3,3-bis-hydroxymethyl-oxacyclobutane (B.Pt. 40 DEG  C. at 0.15 mms.); (10) 3,3 - bis - chloromethyloxacyclobutane boiled with potassium in ethyl alcohol yields 3,3-bis-ethoxymethyloxacyclobutane (B.Pt. 81-82 DEG  C. at 19 mms.); (11) 3,3 - bis - chloromethyloxacyclobutane heated with dry potassium phenate yields 3,3-bis-phenoxymethyloxacyclobutane (M.Pt. 68 DEG  C.).