Abstract: Method for the production of L,L-, D,D-, D,L- and meso-dilactides, comprising the polycondensation and/or polytransesterification of an L-, D- or D,L-lactic acid or of esters thereof to polyesters of higher molecular weights of the L-, D- and D,L-lactic acid (polylactic acids) and cyclizing depolymerization of the polylactic acids to dilactides, wherein the polyesters of higher molecular weights of the L-, D- and D,L-lactic acids are produced in the presence of hydrolysis-stable metal compounds as catalyst.
Type:
Grant
Filed:
November 14, 2008
Date of Patent:
April 30, 2013
Assignee:
Jungbunzlauer Austria AG
Inventors:
Gerald Rafler, Jutta Rafler, Andreas Windsperger, Robert Edlauer, Josef Gass
Abstract: The present invention relates to the use of at least one inorganic nitrate in a fermentation process for producing erythritol using a yeast strain of the Moniliella species as an erythritol-producing microorganism characterized in that the at least one inorganic nitrate is simultaneously used as a main nitrogen source and as a pH regulator in the culture medium, as well as to such an improved method for producing erythritol.
Abstract: Method for the production of L,L-, D,D-, D,L- and meso-dilactides, comprising the polycondensation and/or polytransesterification of an L-, D- or D,L-lactic acid or of esters thereof to polyesters of higher molecular weights of the L-, D- and D,L-lactic acid (polylactic acids) and cyclizing depolymerization of the polylactic acids to dilactides, wherein the polyesters of higher molecular weights of the L-, D- and D,L-lactic acids are produced in the presence of hydrolysis-stable metal compounds as catalyst.
Type:
Application
Filed:
November 14, 2008
Publication date:
December 30, 2010
Applicant:
JUNGBUNZLAUER AUSTRIA AG
Inventors:
Gerald Rafler, Jutta Rafler, Andreas Windsperger, Robert Edlauer, Josef Gass
Abstract: The invention relates to a method for the production of high-molecular homo- and Copolyesters of L-, D- and D,L-lactic acids that comprises the process steps of i) the polycondensation of a lactic acid or polytransesterification of esters thereof to a polymeric lactic acid, ii) the cyclizing depolymerization of the polymeric lactic acid to dilactides, and iii) the ring-opening polymerization of the dilactides or mixtures thereof with suitable comonomers, characterized in that in at least one of the process steps i) to iii), a particulate catalyst and/or a particulate stabilizer, each having an average particle diameter of 1 to 100 nm, is/are used in a heterogeneous reaction mixture.
Type:
Application
Filed:
November 14, 2008
Publication date:
December 16, 2010
Applicant:
JUNGBUNZLAUER AUSTRIA AG
Inventors:
Gerald Rafler, Jutta Rafler, Andreas Windsperger, Robert Edlauer, Josef Gass
Abstract: The present invention relates to the use of at least one inorganic nitrate in a fermentation process for producing erythritol using a yeast strain of the Moniliella species as an erythritol-producing microorganism characterized in that the at least one inorganic nitrate is simultaneously used as a main nitrogen source and as a pH regulator in the culture medium, as well as to such an improved method for producing erythritol.