Patent GB-1032649-A (GB)
Title: Aromatic amide-imide polymers
IPC: C09D5/25
Filed: 1964-10-22
Abstract: Trimellitic anhydride monohalides may be prepared by treating trimellitic anhydride with an excess of a halogenating agent, e.g. SO2Cl2, Cl2CO or PCl5 in a solvent, e.g. benzene, benzyl chloride or petroleum at 10-200 DEG  C.  Trimellitic acid monoesters are prepared by treating the acid with an alcohol, e.g. MeOH or EtOH, at temperatures up to 100 DEG  C.  The product is usually a mixture of the 1- and 2-esters.  Monoesters of trimellityl dichloride are prepared from the corresponding monoester of trimellitic acid, e.g. the methyl ester and phosgene or thionyl chloride, optionally in a polar solvent at temperatures up to 100 DEG  C.ALSO:The invention comprises polymers containing 50-15,000 repeating units of formula <FORM:1032649/C3/1> where R is any of the following <FORM:1032649/C3/2>  X being 1-500.  They may be prepared by interacting trimellitic anhydride monohalide or a monoester of trimellityl dihalide with an aromatic diamine or amine terminated polyamide. The trimellitic anhydride monohalide, e.g. the monochloride, may be prepared by treating the anhydride with an excess of a chlorinating agent, e.g. thionyl chloride, phosgene or PCl5 optionally in a solvent, e.g. benzene, benzyl chloride or petroleum.  The dihalide monoester may be prepared by treating the 1- or 2-ester of the acid or a mixture of the two with thionyl chloride or phosgene at up to 100 DEG  C. optionally in a polar solvent, the monoester being produced by interacting the acid anhydride with the corresponding alcohol, e.g. MeOH or EtOH at up to 100 DEG  C. The diamine may be prepared by reducing the corresponding dinitro-compound.  The main reaction is initially carried out in a solvent, e.g. water, xylene, dimethylacetamide, dimethyl formamide, N-methyl-2-pyrrolidone, or dimethyl sulphoxide, to form an intermediate of formula <FORM:1032649/C3/3> in which R1 is H or C1- 15 hydrocarbon, e.g. lower alkyl, and n = 50-15,000.  The reactants may be in equimolar proportions or up to a 15 mole per cent excess of either may be used. They may be added to a single solvent or dissolved in separate solvents prior to mixing. The reaction mixture may also contain a base, e.g. Na2CO3, triethyl-amine, a basic ion-exchange resin, or borax, a dibasic acid or amide-forming derivative thereof, e.g. iso- or terephthalyl chloride and pyromellitic anhydride. The reaction temperature may be up to 150 DEG .  The final product may be obtained by heating the intermediate at 25-175 DEG  C.  It may be used for making insulating coatings for electrical conductors, shaped articles, films, laminates and varnishes.  In Example 4 an amine terminated polyamide prepared from m-phenylene diamine and iso- and terephthalyl chlorides was used to prepare a polyamide/polyimide. In Example 9 a polyamide/polyimide was coated on to glass cloth. In Example 14 the diamine was prepared by interacting phenylene diamine and m-nitrobenzoyl chloride in aqueous NaOH and reducing the product in butyrolactone and ethanol with H2/Raney nickel.  In Example 7 a polymer made from diamino benzanilide, monomethyl trimellityl dichloride and pyromellitic dianhydride in the presence of Na2CO3, dimethyl acetamide and nylene was heat-cured under reduced pressure to give a cellular product.ALSO:Glass cloth or serving or copper wire, are coated with solutions of a polymer having 50-15,000 repeating units of formula: <FORM:1032649/B1-B2/1> where R1 = C1 - 15 alkyl, the free acyl group is joined to the benzene ring at the 4 or 5 position and R is one of a number of divalent aromatic radicals which may be monomeric or polymeric and may contain ketone groups, ether, sulphides sulphone or amide links or fused benzene rings dissolved in dimethyl acetamide, dimethyl sulphonide, dimethyl formamide, N-methyl-2-pyrrolidone or aqueous NaOH,NH4OH, or NaHCO3.  The coatings are heated to 25-175 DEG C. to convert the repeating unit to <FORM:1032649/B1-B2/2> In Example XI a polymer of diaminobenzanilide, and the monomethyl ester of trimellityl dichloride dissolved in dimethyl acetamide containing Na2 Co3 was applied in 3 coats to glass cloth by alternate dipping and baking.  A fourth coat of the polymer solution was applied by dipping and dried.