Imperial Chemical Industries Limited

Robert Allan Rennie

John Crosby

Robert Michael Paton

John Tanner

Trevor Johnson

Process for the preparation of a mercaptal of an oligosaccharide which process comprises the step of reacting the oligosaccharide with a thiol in the presence of an aqueous halocarboxylic or halosulphonic acid.

Saccharide mercaptals

2,4-DIISOCYANATO BICYCLO (3,3,0)-OCT-6-ENE, A NEW COMPOUND AND ITS PREPARATION AND USE ARE DISCLOSED.

2,4-Diisocyanato bicyclo (3,3,0)-oct-6-ene

A furoxan, especially one in which the furoxan ring is fused to a strained aliphatic ring system, is heated in the presence of sulphur dioxide to give an isocyanate. The process enables furoxans, such as dicyclopentadiene furoxan, which ring-open at temperatures &lt;180.degree. C to be converted into isocyanates. In the absence of sulphur dioxide, may be difficult to control the reaction and, in some cases, no isocyanate is obtained. Diisocyanates prepared by the process may be converted into polyurethanes by reaction with suitable hydroxylic compounds.

Production of isocyanates

3,4-Cycloalkano furoxans are produced and are found to be useful in cross-linking of polymers.

3,4-Cycloalkano furoxans

The liquid phase oxidation of an aromatic compound comprising a benzene ring having at least one unsubstituted carbon atom to an aromatic compound comprising a hydroxy-substituted benzene ring is effected using as oxidant a solution of a tetravalent lead compound in the presence of a strong acid.

Oxidation of aromatic compounds with a tetravalent lead oxidation system

The in situ thermal decomposition of specified furoxans to yield dinitrile oxides is used to modify a polyfunctional species. Preferred uses involve cross-linking of polymers, especially rubbers, but the process may also be used to form polymers from monomeric materials or to bind additives to polymeric substrates. Compositions incorporating polymeric materials and suitable furoxans may be used as 'one-shot' casting systems or be produced in the form of thermally curable sheets, etc, having useful shelf-lives.

Growing community of inventors

Runcorn, United Kingdom

Robert Allan Rennie