To provide a highly heat resistant flame retardant.

A polymer having repeating units represented by the following formula (1), which has a weight average molecular weight as calculated as standard polystyrene of at least 6,000:

##STR00001##

wherein R is a C.sub.1-6 alkylene group, S or SO.sub.2.

A method for treating a shear-thinning residue composition deriving from the synthesis of an aryl ether ketone, the residue composition including a liquid fraction and solid residues, the method including the steps of: passing said shear-thinning residue composition through a shear-generating evaporating device, between a rotating part and a stationary part; and recovering a condensed liquid fraction and separately recover concentrated solid residues.

A method for manufacturing 1,4-bis 4-phenoxybenzoyl) benzene, including: providing a reactant mixture including terephthaloyl chloride and diphenyl ether in a solvent; adding a Lewis acid to the reactant mixture, so as to obtain a product mixture; wherein the temperature of the reactant mixture is greater than 5 C. during at least part of the step of adding the Lewis acid to the reactant mixture.

The invention relates to a method for manufacturing 1,4-bis(4-phenoxybenzoylbenzene), comprising: providing a reactant mixture comprising terephthaloyl chloride and diphenyl ether in a solvent; adding a Lewis acid to the reactant mixture, so as to obtain a product mixture; wherein the temperature of the reactant mixture is greater than 5 C. during at least part of the step of adding the Lewis acid to the reactant mixture.

Polyaryletherketones are produced which are end-capped with a phenylethynyl-containing moiety. The end-capped material, having a relatively low molecular weight, may be subjected to a thermal cycle to produce a higher molecular weight material having excellent mechanical properties, a relatively high level of crystallinity and acceptable Tm and Tg

Described here are blocky PEEK copolymers and corresponding synthesis methods. It was surprisingly found that synthesis of blocky PEEK copolymers in a non-solvent environment with respect to PEEK produced blocky PEEK copolymers with high degrees of functionalization and crystallinity. The blocky PEEK copolymers had an increased blocky structure, relative to corresponding PEEK copolymer synthesized with other known methods. Moreover, membranes formed from the blocky PEEK polymers are particularly desirable in fuel cell applications. For example, the membranes formed from the blocky PEEK polymers had surprisingly large ion conductivities as well as significantly improved chemical and thermal resistance, at least in part, to the improved functionalization and crystallinity.

The present specification relates to a compound comprising an aromatic ring, a polyelectrolyte membrane comprising the same, a membrane-electrode assembly comprising the polyelectrolyte membrane, a fuel cell comprising the membrane-electrode assembly, and a redox flow battery comprising the polyelectrolyte membrane.

A composition comprising: (i) a polymeric material (A) having a repeat unit of formula
(O-Ph)n-O-Ph-O-Ph-CO-Ph-I and a repeat unit of formula
O-Ph-Ph-O-Ph-CO-Ph-II wherein Ph represents a phenylene moiety and n represents 0 or 1; and (ii) a polymeric additive comprising one or more of: (a) a polycarbonate; and/or (b) a polymeric material (B) which includes a repeat unit of general formula ##STR00001## wherein R.sup.1 and R.sup.2 independently represent a hydrogen atom or an optionally-substituted (preferably un-substituted) alkyl group, and R.sup.3 and R.sup.4 independently represent a hydrogen atom or an optionally-substituted alkyl group, an anhydride-containing moiety or an alkyloxycarbonyl-containing moiety.

A method for manufacturing 1,4-bis(4-phenoxybenzoylbenzene), including: reacting terephthaloyl chloride with diphenyl ether in a reaction solvent and in the presence of a Lewis acid, so as to obtain a product mixture including a 1,4-bis(4-phenoxybenzoylbenzene)-Lewis acid complex; contacting the product mixture with a protic solvent, so as to obtain a first phase containing the Lewis acid and a second phase containing 1,4-bis(4-phenoxybenzoylbenzene); subjecting at least the second phase to a solid/liquid separation step by centrifugal filtration, so as to recover solid 1,4-bis(4-phenoxybenzoylbenzene).

Provided is a polymer electrolyte article having high proton conductivity, mechanical strength, and chemical stability, wherein, for the average periodic distance in the phase-separated structure of the polymer electrolyte article observed by small-angle X-ray scattering, the average periodic distance in the atmosphere and the average periodic distance in water satisfy the following condition: (the average periodic distance in water)/(the average periodic distance in the atmosphere)?2.20.