反应详情

Further, in a process for preparing a polyester according to the present invention, crude 1,2-butanediol (hereinafter referred to as crude 1,2-BG) containing acetoxyhydroxybutane and/or diacetoxybutane may be used as 1,2-butanediol. Crude 1,2-BG is usually formed as a by-product during the preparation of 1,4-butanediol by the reaction of butadiene with acetic acid, such crude 1,2-BG contains various acetoxy compounds. For instance, from a gas chromatography analysis, a typical sample of such crude 1,2-BG has been found to have a composition comprising 54% by weight of 1,2-BG, 23% by weight of 1-acetoxy-2-hydroxybutane, 8% by weight of 1-hydroxy-2-acetoxybutane, 10% by weight of 1,2-diacetoxybutane and 5% by weight of other substances such as 1,3-butanediol and 1,4-butanediol, and thus it has been found that the major components of the impurities are acetoxy derivatives of 1,2-BG.