Aromatic polyethersulphones having --OCH.sub.2 COR end groups
AssigneeImperial Chemical Industries PLC
InventorJohn Stuart-Webb
Life of this patent
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Abstract
Aromatic polyethersulphones that are particularly useful as adhesives and coatings having end groups of formula --OCH.sub.2 COR, where R is alkyl or alkoxy. Preferred examples are --OCH.sub.2 COCH.sub.3 and --OCH.sub.2 COOC.sub.2 H.sub.5. Such polymers may be made by heating polyethersulphones made from halophenates or bisphenate/dihalide mixtures, in the presence of a reagent of formula XCH.sub.2 COR (X is halogen, preferably chlorine), such as chloroacetone or ethyl chloroacetate, for a short period of time. Such polymers of molecular weight (RV<0.25) are of particular use in coating compositions comprising a dispersion of a fluorocarbon polymer dispersed in a solution or dispersion of the polyethersulphone.
Claims6
An aromatic polyethersulphone containing repeat units of the general formula
- --E--O--E'--O--
- or, where E is the same as E',
- --E--O--
- in which E is the residuum obtained by the removal of the halogen atoms of a dihalobenzenoid compound in which each halogen atom is activated by an --SO.sub.2 -- group ortho or para thereto, and E' is the residuum obtained by removal of the hydroxyl groups from a bisphenol;
- or where E is the same as E', it is the residuum obtained by the removal of the halogen atom and the hydroxyl group from a halophenol in which the halogen atom is activated by an --SO.sub.2 -- group ortho or para thereto, said polyethersulphone having from 3 to 20 end groups of the formula --OCH.sub.2 COR where R is alkyl or alkoxy, per 100 repeat units.
A process for the production of an aromatic polyethersulphone in which 3 to 20 of the end groups per 100 repeat units are groups having the formula --OCH.sub.2 COR where R is alkyl or alkoxy, wherein said process comprises heating
- (i) an alkali metal halophenate, or
- (ii) a mixture of substantially equimolar proportions of
- (a) an alkali metal bisphenate, or
- (b) a bisphenol and an alkali metal carbonate or bicarbonate, and a dihalobenzenoid compound,
- in which halophenate or dihalobenzenoid compound each halogen atom is activated by an --SO.sub.2 -- group ortho or para thereto, and then heating the polyethersulphone so formed under anhydrous conditions with a reagent of formula XCH.sub.2 COR, where X is halogen, and R is alkyl or alkoxy, to form the aromatic polyethersulphone.
Dependencies are inferred from the claim text.