Patent GB-1343287-A (GB)
Title: Heterocyclic polymers and their method of manufacture
IPC: C08G73/06
Filed: 1970-11-20
Abstract: 1343287 Polyquinazolines OFFICE NATIONAL D'ETUDES ET DE RECHERCHES AEROSPATIALES 20 Nov 1970 [21 Nov 1969] 55435/70 Heading C3R Polyquinazolines are described having in the chain nuclei of the formula in which the non-heterocyclic ring represents an arylene nucleus which is unsubstituted or substituted by one or more C 1-5  alkyl, C 1-5  alkoxy, or nitro radical(s) or halogen atom(s), the quinazoline nuclei being linked with one another, either (1) at their 2 positions through a direct linkage or an arylene radical and at their 4 positions through a direct linkage or an arylene, alkylene or alkylarylene radical; or (2) at their 2-positions through an arylene radical and at one of their 5-8 positions through a direct linkage or a bivalent radical X such as -O-, -CH 2 -, -SO 2 -, -CO- or -S-, the quinazoline nuclei bearing an aliphatic or aromatic radical P, at the 4 positions, or (3) at their 4 positions through a direct linkage or through an arylene, alkylene or aralkylene radical and at one of their 5-8 positions directly or through a bivalent radical X, the quinazoline nuclei bearing an aromatic radical Q at the 2-positions. The polyquinazolines can be prepared by reacting compounds containing two functional groups selected from (a) and (b) a nitrile group, in the presence of a Lewis acid such as AlCl 3 , FeCl 3 , SnCl 4  or SbCl 5 , in a Friedel and Crafts type solvent, e.g. nitrobenzene, o-dichlorobenzene or tetrachloroethane at a temperature of 60-180 C. In method (1) a diiminochloride of formula or of the formula is reacted with a dinitrile N#C-R 4 -C#N to give polyquinazolines of the respective formulae where R 2  represents a direct linkage or an arylene radical, and R 4  a direct linkage or an arylene, alkylene or aralkylene radical. In method (2) compounds having one of the general formulae are polycondensed resulting in polyquinazolines of the respective formulae  In method (3) a polyiminochloride in which the basic unit contains the group is reacted with a nitrile P-C#N. The preferred polyiminochloride comprises recurring units of the formula which results in polyquinazolines of the formula The compounds and polymers containing the iminochloride groups are prepared first from their corresponding amide by the action of an acid chloride such as PCl 5  and SOCl 2  at 80- 120 C. The conversion of the amide to the iminochloride and the subsequent formation of the polyquinazoline may be effected in the same solvent with or without intermediate separation of the iminochloride. Amides and nitriles used in the examples for preparing polyquinazolines by method (1) are N,N<SP>1</SP>-dibenzoylbenzidine, isophthalodianilide, terephthalodianilide, isophthalodinitrile and terephthalodinitrile; and by method (2) parabenzoylaminobenzonitrile, and by method (3) poly(diphenyl-isophthalamide), polydiphenylether-isophthalamide, poly(diphenylmethaneisophthalamide), poly(diphenylsulponeisophthalamide), poly(diphenylether terephthalamide), poly(diphenylsulphoneterephthalamide), poly(diphenylterephthalamide), poly(diphenylmethane-terephthalamide), benzonitrile and acetonitrile.