Raychem Limited

Viktors Jansons

Heinrich C Gors

Klaus J Dahl

Patrick J Horner

Stephen S Moore

Richard Harold Whiteley

Robert H Reamey

Paul Becker

Ryan W Dupon

Paul B Germeraad

Alan J Gotcher

Stephen L Tondre

Alan S Yeung

Pawel Czubarow

Anthony C Evans

John B Mazzanti

Mark A Bannick

George A Divers, Iii

Novel polyester compositions, particularly suitable for the insulation of wires, contain an aromatic polyester, especially polybutylene terephthalate. The presence of certain tin (II) compounds, for example tin (II) oxide, oxalate, phthalate, pyromellitate, or phosphite, reduces the flammability and smoke generation of such compositions. The presence of an aliphatic polyester, and optionally a thermoplastic elastomer, can also improve the properties of such compositions.

Polyester compositions

An electrode is formed on a substrate such as a varistor, a PTC ceramic, or a piezoelectric ceramic by coating a surface of the substrate with a combination of a metal source and a source of reducing carbon. The substrate and/or the combination is an absorber of microwave radiation. Irradiation with microwave radiation causes a carbothermic reduction to occur, converting the metal source to a metal electrode on the substrate.

Method of forming an electrode on a substrate

Novel aromatic poly(ether ketones) having imide, amide, ester, azo, quinoxaline, benzimidazole, benzoxazole, or benzothiazole groups, comprising, for example, a repeat unit ##STR1## are prepared by Friedel Crafts polymerization.

Aromatic polymers

Aromatic carbonyl compounds, in particular arylene ether ketones, are prepared by reacting an appropriate reagent system in the presence of free Lewis acid and a complex between a Lewis acid, for example, aluminum trichloride, and an inorganic salt controlling agent, for example, lithium chloride, and, optionally, a diluent, such as methylene chloride. The process is particularly advantageous for the preparation of substantially or all para-linked arylene ether ketones as the presence of the Lewis acid/Lewis base complex markedly reduces alkylation and ensures the substantial absence of ortho substitution.

Friedel-crafts preparation of aromatic ketones with an inoganic salt

A process for producing an aromatic polyketone which comprises polymerizing an appropriate monomer or monomers by a Friedel-Crafts polymerization reaction using a Lewis acid catalyst. A controlling agent such as a Lewis base may be added to the reaction medium and/or the reaction is conducted under specified conditions to control the reaction. The reaction medium comprises, for example, aluminum trichloride as the Lewis acid, an organic Lewis base such as N,N-dimethylformamide or an inorganic Lewis base such as sodium or lithium chloride, and a diluent such as methylene chloride or dichloroethane. The amount of Lewis acid, the amount of Lewis base, the temperature of the reaction and the monomer to diluent molar ratio are varied depending on the monomer system to obtain melt-processable, high molecular weight, substantially linear polymers, for example poly(carbonyl-p-phenylene-oxy-p-phenylene), poly(carbonyl-p-phenylene-oxy-p-phenylene-oxy-p-phenylene), and the like. Copolymers containing up to 30% by weight of an aromatic sulfonyl halide comonomer can also advantageously be produced by this process.

Preparation of aromatic polymers using a specified quantity of Lewis acid

Aromatic oligomers, in particular arylene ketone and arylene sulfone oligomers, are prepared by reacting an appropriate monomer system in the presence of free Lewis acid and a complex between a Lewis acid, for example, aluminum trichloride, and a Lewis base, for example, N,N-dimethylformamide, and, optionally, a diluent, such as methylene chloride. The process is particularly advantageous for the preparation of substantially or all paralinked arylene ether ketone oligomers as the presence of the Lewis acid/Lewis base complex markedly reduces alkylation and ensures the substantial absence of ortho substitution. The monomer system can be, for example, a self-reacting monomer such as p-phenoxy-benzoyl chloride or a two-monomer system such as 1,4-diphenoxybenzene and terephthaloyl chloride.

Preparation of aromatic oligomers

Novel aromatic polymers

A method of preparing 4,4'-diphenoxybenzophenone, comprising reacting diphenyl ether and carbon dioxide in the presence of a Friedel-Crafts catalyst and a promoting agent, preferably selected from the group consisting of phosphoryl chloride, phosphorus pentoxide, tetrachlorosilane, methyltrichlorosilane, dimethyldichlorosilane, titanium tetrachloride, zirconium tetrachloride, zirconium oxyhalide, and phosphorus pentachloride. In a preferred embodiment, the Friedel-Crafts catalyst is aluminum chloride and the promoting agent is phosphoryl chloride.

Preparation of 4,4'-diphenoxybenzophenone

A method of preparing a poly(arylene ether ketone) having a repeat unit ##STR1## comprising polymerizing a monomer system comprising (I) a monomer of the formula ##STR2## and (II) a monomer of the formula ##STR3## wherein R.sup.1 is p-phenylene, m-phenylene, or 4,4'-biphenylene;

Preparation of poly(arylene ether ketones)

Aromatic carbonyl compounds, in particular arylene ether ketones, are prepared by reacting an appropriate reagent system in the presence of free Lewis acid and a complex between a Lewis acid, for example, aluminum trichloride, and a Lewis base, for example, N,N-dimethylformamide, and, optionally, a diluent, such as methylene chloride. The process is particularly advantageous for the preparation of substantially or all para-linked arylene ether ketones as the presence of the Lewis acid/Lewis base complex markedly reduces alkylation and ensures the substantial absence of ortho substitution.

Friedel-crafts preparation of aromatic ketones

This invention relates to novel copolymers derived from diphenyl ether, terephthalic acid derivative and a third monomer of the formula ##STR1## where n=1 or 2. The copolymers can be prepared by Friedel-Crafts polymerization. Preferred copolymers are derived from diphenyl ether, terephthaloyl chloride, and 1,4-diphenoxybenzene.

Aryl ether ketone copolymers

A method for preparing poly(aryl ether ketones) having the repeat unit of the formula

Method for preparing poly(aryl ether ketones)

Preparation of aromatic polymers

The preparation of poly(arylene ether ketones) by Friedel-Crafts polymerization, in the presence of a Lewis acid catalyst and a diluent, is conducted under conditions in which the polymer and/or its complex with the catalyst is suspended in the diluent during at least part of the polyreaction mixture if desired. The dispersant may be a polymer or an organic compound containing at least eight carbon atoms and is preferably a Lewis base. The dispersant preferably contains at least one molecular segment substantially compatible with the poly(arylene ether ketone) or its complex with the Lewis acid and substantially incompatible with the diluent and at least one molecular segment substantially compatible with the diluent and substantially incompatible with the poly(arylene ether ketone) or its complex with the Lewis acid.

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Los Gatos, CA, United States of America

Viktors Jansons