Patent GB-1071901-A (GB)
Title: Polyamides
Inventor: PRUCKMAYR GERFRIED
IPC: C08G73/10
Filed: 1965-01-11
Abstract: Fusible amide-esters of less than 0.2 inherent viscosity contain at least one unit of formula <FORM:1071901/C3/1> in which R1 is an aromatic radical such that the 4 carbonyl groups are in two pairs, the two in each pair being ortho- or perito each other, R2 is alkyl or aryl and R3 is arylene such that the two amino groups are separated by at least 3 carbon atoms.  They may be prepared by heating the corresponding tetracarboxylic acid tetraester and diamine in the molar ratio 0.9-1.5:1.  Esters specified include the phenyl, methyl, biphenyl, naphthyl, cresyl, dichlorophenyl, ethyl and butyl esters, of benzophenone-3,31, 4,41-tetracarboxylic, pyromellitic, acids and mixtures thereof.  Diamines specified include bis(aminophenyl)ethers, bis(aminophenyl) methanes, 2,2 - bis(aminophenyl)hexafluoropropanes, 2,2 - bis(aminophenyl)propanes, diamino - m - xylenes, bis(aminophenyl)-sulphone, benzidine, m-phenylene diamine, naphthylene diamines, anthrylene diamines, furylene diamines, benzfurylene diamines, bis-(aminophenyl) difluoromethanes, diaminobenzophenones, and bis(aminophenyl)sulphides.  Particles of ester and amine may be mixed, melted and then heated to 200-300 DEG  C.  The product may be a mixture of compounds containing 1-5 or more of the units specified optionally together with units in which 3 or 4 of the ester groups in one molecule have been converted to amide groups.  If isomerism is possible at R1 a mixture of isomers will be obtained.  It may melt between 50 DEG  and 200 DEG  C., be soluble in organic solvents, many of which are specified, and be converted to the corresponding polyimide by heating above 250 DEG  C.  Before conversion to the polyimide it may be mixed with fillers, pigments, carbon black, metal particles, abrasives, dielectrics, lubricating polymers and polybenzimidazoles prepared by heating a diester of an aromatic dicarboxylic acid, e.g. iso- or terephthalic or a triester of a tricarboxylic acid, e.g. trimesic, with a tetra-amine, e.g. 3,31-diamino-benzidine in the ratio 1:09-1.4.  This latter material which may have an inherent viscosity of 0.04-0.12 may be mixed with 60-90% of the ester-amide.  The mixture may be used for coating and sticking metal surfaces.  It may be foamed by incorporating a blowing agent or dispersing air, CO2 or nitrogen in a melt or solution.ALSO:Surfaces may be coated with a mixture of amide-ester isomers containing units of formula:  <FORM:1071901/B1-B2/1> where R1 is aromatic, its valencies being in 2 pairs the members of each pair being ortho or peri to each other, R2 is alkyl or aryl and R3 is aromatic its 2 valencies stemming from carbon atoms which are separated by at least one other carbon atom which may then be heated to convert it to a polyimide.  The mixtures may be applied as melts or solutions in dioxan, tetrahydrofuran, methylene chloride, chloroform, pyridine, hexamethylene phosphoramide, dimethyl sulphoxide, dimethyl formamide, or dimethyl acetamide by brushing, spraying, rolling, dipping and doctoring.  Substrates listed are: steel, aluminium, copper, brass and other metals in the form of sheets, fibres, wires, and screening, asbestos, glass in the form of sheets, fibres, foam and fabrics, cellulose resins, polyolefins, polyesters, polyamides, polyimides, polyfluorocarbons, or polyurethanes in the form of sheets, fibres, films, fabrics and screening and leather.