Method for the production of polyoxymethylene dialkyl ethers from trioxane and dialkylethers

A process for preparing polyoxymethylene dialkyl ethers of formula: H2m+1CmO(CH2O)nCmH2m+1 where n is 2 to 10, m independently is 1 or 2 is disclosed, in which a dialkyl ether selected from dimethyl ether, methyl ethyl ether or diethyl ether and trioxane are fed into a reactor and reacted in the presence of an acid catalyst, whereby the amount of water introduced into the reaction mixture with the dialkyl ether, trioxane and/or the catalyst is less than 1 % by weight based on the reaction mixture.