Patent GB-886978-A (GB)
Title: Polyphenyl ethers
IPC: C10M173/02
Filed: 1959-11-19
Abstract: Polyphenyl polyethers comprising at least three, preferably 4 to 8, benzene nuclei connected to one another by oxygen atoms, there being at least one meta dioxyphenylene group, are effective lubricants for metal surfaces at high operating temperatures and/or in the presence of ionizing radiation.  The specification includes tables showing the flash point, fire point, initial decomposition temperature, viscosities at 100 DEG , 210 DEG , 400 DEG  and 600 DEG F., oxidation stability and coking resistance of m-diphenoxybenzene, bis(m-phenoxyphenyl)-ether, m-phenoxyphenyl-p-phenoxyphenyl ether, p-bis(m-phenoxyphenoxy) benzene, m-bis(m-phenoxyphenoxy) benzene, and m-bis[m-(p-phenoxyphenoxy) phenoxy] benzene compared with polyphenyl polyethers containing no meta dioxyphenyl groups, and with other lubricants.  Where temperatures below 300 DEG F. are anticipated during the useful life of the lubricant, pour point depressants and viscosity index improvers such as the polymers of acrylic acid esters or of 2-alkyl acrylic acid esters may be utilized.  It may be desirable to subject the polymers to a shearing action, e.g. by passing them through an injector nozzle, before incorporating them in the compositions.  Suitable anti-lacquering agents for addition to the compositions are salts of aromatic carboxylic acids or of phenols with a metal of Group II of the Periodic Table.  Particularly effective additives of this type are the zinc salts of alkylated salicyclic acids containing 8 to 20 carbon atoms in the alkyl group. Extreme pressure additives may be added, such as trioctyl phosphate, tricresyl phosphate, monobutyl hydrogen trichloromethyl-phosphonate and its salts with di(2-ethylhexyl) amine.  For the preparation of the polyphenyl polyethers see Group IV(b).ALSO:Polyphenyl polyethers comprising at least four benzene nuclei connected to one another by oxygen atoms, there being at least one metadioxyphenylene group, are prepared by heating, in the presence of copper powder, a halogenated benzene hydrocarbon, a halogenated polyphenyl ether or polyether with an alkali metal salt of a phenol, a phenoxyphenol or a polyphenoxyphenol.  In Example 3, a mixture of m-phenoxyphenol and potassium hydroxide pellets is heated under vacuum until no more water is evolved. Copper catalyst is added, and the mixture is heated to 180 DEG C. in an atmosphere of nitrogen.  p-Dibromobenzene is then gradually added with stirring; and the mixture is heated at about 220 DEG C. for 7 hours.  The product is extracted with benzene, and the extract is distilled under reduced pressure to isolate p-bis(m-phenoxyphenoxy) benzene <FORM:0886978/IV (b)/1> Example 4 describes the preparation of an ether having 7 benzene nuclei joined by 6 oxygen atoms - [meta - bis meta - (para - phenoxy - phenoxy)phenoxy] benzene, by reacting sodium meta (p-phenoxyphenoxy) phenol with m-dibromobenzene.  These polyphenyl polyethers have use as lubricants (see Group III). Suitable additives are salts of alkylated hydroxy-benzoic acids which may be produced (a) by reacting salicylic acid or 4-hydroxybenzoic acid with a mixture of alkenes obtained by cracking paraffin wax, or with a mixture of alcohols, or (b) from alkylated phenols by the Kolbe-Schmidt reaction.  The zinc salt of a mixture of alkyl salicylic acids, made by alkylating phenol with a mixture of alkenes containing 14 to 18 carbon atoms in the molecule and converting the resulting alkyl phenols into the corresponding salicylic acids, is referred to.