Patent GB-1135462-A (GB)
Title: Aromatic polyamides
Inventor: JONES MICHAEL EDWARD BENET
IPC: C08G69/32
Filed: 1966-05-13
Abstract: 1,135,462. Aromatic polyamide. IMPERIAL CHEMICAL INDUSTRIES Ltd. 13 May, 1966 [21 May, 1965], No. 19751/66. Divided out of 1,128,807. Heading C3R. Amorphous or at most weakly crystalline and non-crystallizable aromatic polyamides are derived from (i) an aromatic diprimary amine in which the amino groups are on non-adjacent carbon atoms and which is either (a) a compound containing a benzene ring carrying 2 meta-amino groups, (b) a compound containing 2 benzene rings each carrying an amino group linked together by -O-, -S-, -SO-, -S-S-, -NR- where R is a saturated hydrocarbon group or a substituted derivative thereof or a tetravalent carbon atom where each of the 2 other valencies is linked to an H or C atom or (c) a diamino-derivative of a fused aromatic polycyclic compound and (ii) an aromatic dicarboxylic acid in which the carboxyl groups are on non-adjacent carbon atoms and which is either (a) a compound containing a benzene ring carrying 2 carboxyl groups and on one other carbon atom an -OR group or (b) a compound containing 2 benzene rings linked by a group -O(ArO) n - where Ar is phenylene and n=0 or 1, each benzene ring carrying a carboxyl group and being unsubstituted or substituted by -R, -OR, or SR with the proviso that not all the diamide units are derived from 4,4<SP>1</SP>-dicarboxydiphenyl ether and either meta-phenylene diamine or 4,4<SP>1</SP>-diaminodiphenyl ether, up to 10% of the aromatic diamine and dicarboxylic acid may be replaced by aliphatic amine or dicarboxylic acid and up to 50 mole per cent of the diamine and dicarboxylic acid of the invention may be replaced by other aromatic diamines and dicarboxylic acids. Diamines specified include m-phenylene diamine, 2,4- diamino toluene, 3,5-diamino-o-xylene, 2,4- diaminochlorobenzene, 2,4-diaminobromo benzene, 2,4 - diaminoanisole, diaminotriphenylmethanes, bis-(2-chloro-4-aminophenyl) -ether, bis - (2 - isopropoxy - 4 - aminophenyl) - methane, bis - (4 - aminophenyl) - ether, bis - (4 - aminophenyl) - sulphoxide, bis - (4 - aminophenyl) - methane, 2,2 - bis - (4 - aminophenyl)- propane and 1,5 - diaminonaphthalene. A minor proportion of the diamine may be replaced by another diamine, e.g. bis-(4-aminophenyl)-sulphone. Dicarboxylic acids specified include: a 2-, 4- or 5-alkoxyisophthalic acid, e.g. 4-methoxyisophthalic acid, bis-(4-carboxyphenyl)-ether, 1,2-bis-(4-carboxyphenoxy)-ethane, 2 - methoxy - isophthalic acid, methoxyterephthalic acid, n-propoxyterephthalic acid, and p-bis(4-carboxyphenoxy)-benzene. A minor proportion of the acid may be replaced by another dicarboxylic acid, e.g. isophthalic acid. The reactants may be polymerized in bulk or interfacially. However, preferably the diamine or a salt thereof is reacted with the dihalide of the dicarboxylic acid in an organic solvent for both reactants at about - 20‹ C. and under a nitrogen atmosphere. A surface-active agent and a base may be present. Solvents specified include 2,4-dimethyl cyclic tetramethylene sulphone, methyl ethyl ketone, acetonitrile, cyclic tetramethylene sulphone, hexamethyl phosphoramide, tetramethyl urea, N,N-dialkyl aliphatic carboamides having at least 2 carbon atoms, e.g. N,N-dimethyl acetamide, propionitrile and polyhalogenated hydrocarbons, e.g. CH 2 Cl. Bases specified include pyridine and sodium carbonate. Surface-active agents specified include sodium lauryl sulphate. Water may also be present. The products may be made into films or fibres which may be drawn, or used for coatings.