摘要 |
The invention relates to a method for synthesis of aliphatic isocyanates from aromatic isocyanates in substantially 3 stages. In particular, the invention relates to a method for synthesis of bis{4-isocyanatocyclohexyl}methane (H12MDI) from bis{4-isocyanatophenyl}methane (MDI). More especially, the invention relates to a method for synthesis of H12MDI with a trans-trans isomer content of <30%, preferably of <20%, particularly preferably of 5 to 15%.
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