Ticona Gmbh

Hoechst Aktiengesellschaft

Horst Röschert

Michael Haubs

Michael Hoffmockel

Robert M Gronner

Michael G Yearwood

Satyajit Verma

Hans-Jerg Kleiner

Karl-Friedrich Muck

Dieter Regnat

Karl-Friedrich Mück

An initiator for cationic polymerization comprises a salt of a protic acid as well as a protic add. The molar ratio of protic acid to salt is in the range from 1:0.01 to 1:2000. The initiator is used for example for cationic homo- or copolymerization of trioxane, and permits stable and flexible operation of the polymerization.

Initiator

An initiator for cationic polymerization comprises a salt of a protic acid as well as a protic acid. The molar ratio of protic acid to salt is in the range from 1:0.01 to 1:2000. The initiator is used for example for cationic homo- or copolymerization of trioxane, and permits stable and flexible operation of the polymerization.

A process for the preparation of polyoxymethylene copolymers, wherein 1,3,5-trioxane is polymerized with generally known comonomers in the presence of a strong protonic acid initiator and in the presence of a formaldehyde dialkyl acetal, and wherein the initiator is dissolved in the formaldehyde dialkyl acetal before admixing to the trioxane and the comonomers.

Process for the preparation of thermally stable polyoxymethylene copolymers

Process for the preparation of thermally stable polyoxymethylene

The present invention relates to a process for preparing 2,2'-bis(diphenylphosphinylmethyl)-1,1'-binaphthyls by reacting a reaction mixture prepared in a solvent by reaction of 2,2'-dimethyl-1,1'-binaphthyl with a brominating agent to produce a mixture comprising 2,2'-bis(bromomethyl)-1,1'-binaphthyl and further brominated binaphthyls and optionally further comprising unreacted brominating agent, reacted brominating agent and solvent, with an alkyl diphenylphosphinite of the formula RO--P(Ph--(R').sub.n).sub.2, where R is an alkyl radical having from 1 to 5 carbon atoms, Ph is phenyl, R' is an alkyl radical having from 1 to 4 carbon atoms, CF.sub.3, fluorine, chlorine or bromine and n is 0, 1 or 2, at from 70.degree. to 180.degree. C. optionally in the presence of a further solvent.

Process for preparing

Growing community of inventors

Ober-Hilbersheim, Germany

Horst Röschert