Abstract: The novel process for preparing dialkyl dicarbonates by reacting the corresponding alkyl haloformates with alkali metal hydroxides, alkaline earth metal hydroxides and/or carbonates in the presence of water-immiscible organic solvents and in the presence of a catalyst is characterized in that the catalyst used is at least one tertiary alkylamine of the formula (I) NR1R2R3,??(I) where the substituents are each as defined in the description.
Type:
Grant
Filed:
April 30, 2005
Date of Patent:
September 2, 2008
Assignee:
Lanxess Deutschland GmbH
Inventors:
Thomas Prinz, Markus Eckert, Hans-Ulrich Buschhaus, Steffen Kahlert
Abstract: The present invention relates to a peroxide curable rubber compound containing at least one elastomeric polymer comprising repeating units derived from at least one C4 to C7 isomonoolefin monomer, at least one C4 to C14 multiolefin monomer, at least one p- or m-alkylstyrene monomer and at least one co-agent.
Abstract: A method of using Raman Spectra for determining the progress of a graft polymerization reaction is disclosed. The method entails (a) measuring at the beginning of the reaction and at a plurality of time intervals in the course of the reaction, continuously and on-site, the Raman spectrum in the wave number range of 100 to 4000 cm?1 of one or more of the monomers and/or polymers entailed in the reaction and of at least one internal standard and (b) recording the spectra and (c) adding reaction partners necessary to the reaction continuously and/or discontinuously and (d) calculating the change in concentration of the monomers and polymers by comparing the spectra of the monomers or polymers with the internal standard.
Type:
Grant
Filed:
October 28, 2002
Date of Patent:
October 17, 2006
Assignee:
Bayer Aktiengesellschaft
Inventors:
Udo Wolf, Ralf-Jürgen Born, Vera Buchholz, Herbert Eichenauer, Eckhard Wenz, Wilhelm Bergmeier, Christof Boden