Patent GB-835464-A (GB)
Title: Linear polycarbonate resins
IPC: C08G64/04
Filed: 1957-06-21
Abstract: Dihydroxy aromatic ethers are made by reacting a halogenated etherified phenol with a phenoxide having an etherified phenolic hydroxy group in the presence of copper powder to give an aromatic ether having an etherified phenolic hydroxyl group on each aromatic nuclear and then converting the etherfied hydroxyl groups into hydroxyl groups by treatment with a hydrogen halide or an aluminium halide, preferably in the presence of an acid anhydride.  In examples: (1) and 2) p,p1-dihydroxydiphenyl ether is made by firstly reacting a mixture of p-bromoanisole, p-methoxyphenol and potassium hydroxide in the presence of copper powder to give p,p1-dimethoxydiphenyl ether and secondly di-methylating this product by refluxing it with a mixture of acetic anhydride and hydrobromic acid; (8) 4,41-dihydroxy-3,31-dimethyldiphenyl ether is similarly prepared from o-methyl-p-bromoanisole, o-methyl-p-methoxy phenol and potassium hydroxide; (9) A chlorinated p,p1-dihydroxydiphenyl ether is made by chlorinating p,p1-dimethoxydiphenyl ether and demethylating the product.  Specification 835,465 is referred to.ALSO:New linear aromatic polycarbonate resins contain the residues of a dihydroxy aromatic ether having the formula <FORM:0835464/IV (a)/1> where A is the residue of an aromatic nucleus, Y is an organic or inorganic radical inert in the polycarbonate forming reaction, m is 0 or a whole number equal to from 1 to a maximum equal to the number of replaceable nuclear hydrogen atoms on the hydrocarbon radical A and q is 1 or more.  The inert radical Y may be a halogen atom, a nitro group, or a radical of formula R or OR, where R is a monovalent hydrocarbon radical or halogen substituted hydrocarbon radical.  The polycarbonates may be made (1) by effecting ester-interchange between the dihydroxy aromatic ether and a diaryl, dialkyl or dicycloalkyl carbonate preferably at 150-300 DEG  C., in an inert atmosphere and in the later stages of the reaction under reduced pressure and, if desired, in the presence of an ester-interchange catalyst, e.g. metallic Li, K, Ca, Be, Mg, Zn, Cd, Al, Cr, Mo, Fe, Co, Ni, Cr, Ag, Au, Sn, Sb, Pb, Ba, Sr, Pt or Pd or their alcoholates, oxides, carbonates, acetates or hydrides; (b) by introducing phosgene into a solution of the dihydroxy aromatic ether in an organic base (e.g. pyridine, dimethylaniline or quinoline), if desired diluted with an organic solvent, preferably at 0-100 DEG  C., the polycarbonate being precipitated at the end of the reaction by pouring the solution into a suitable liquid (e.g. water, a hydrocarbon or an alcohol); or (c) by reacting phosgene with an aqueous solution of a soluble salt of the dihydroxy aromatic ether whereby a low molecular weight polycarbonate is precipitated which may be converted into higher molecular weight products either by neutralizing it, washing it and reacting it with a diaryl carbonate or by adding a solvent to the water or by forming an aqueous organic emulsion which keeps the polycarbonate in solution and enables further reaction to take place.  The polycarbonates are soluble in dioxane and may be used (a) in moulding powders, if desired with fillers such as wood flour, diatomaceous earth, carbon black or silica for the manufacture of gears, ratchets, bearings, cams, impact parts, gaskets or valve seats; (b) for the manufacture of films which may be oriented and are useful as containers, covers, closures, pipe coverings, sound recording tapes or electrical insulating tapes; (c) as surface coatings; (d) as wire coatings, wire enamels and slot insulation in dynamoelectric machines; (e) in varnishes and paints; (f) as bonding materials for fibrous or metallic laminates; and (g) as fibres which may be oriented. Specification 835,465 is referred to.