| 摘要 |
The present invention relates to a process for preparing methacrylic acid or methacrylic esters, comprising the process steps of IA) preparing 3-hydroxyisobutyric acid by a process comprising the process step of contacting a cell which has been genetically modified with respect to its wild type such that, in comparison to its wild type, it is capable of forming more 3-hydroxyisobutyric acid or polyhydroxyalkanoates based on 3-hydroxyisobutyric acid, with a nutrient medium comprising, as the carbon source, carbohydrates, glycerol, carbon dioxide, methanol, L-valine or L-glutamate, under conditions under which 3-hydroxyisobutyric acid or polyhydroxyalkanoates based on 3-hydroxyisobutyric acid are formed from the carbon source, if appropriate purifying the 3-hydroxyisobutyric acid to free it of the nutrient medium and if appropriate neutralizing the 3-hydroxyisobutyric acid, IB) dehydrating the 3-hydroxyisobutyric acid to form methacrylic acid and if appropriate esterifying methacrylic acid. The invention also relates to a process for preparing polymethacrylic acid or polymethacrylic esters. |
