The Study Of The Synthesis Of The 1,3;2,4-Dibenzylidene Sorbitol

In this text, the applications of the 1,3;2,4-Dibenzylidene Sorbitol and its derivatives like p-Me-DBS, p-Cl-DBS in the plastics, rubber, dope, and other fields were introduced firstly, and besides that, the study situation, the market foreground and the development significance were discussed. And then the technical process of the synthesis of the 1,3;2,4-Dibenzylidene Sorbitol, the principle of the chemical synthesis reaction and the method of the preparing about the synthesis of the product were summarized. The mechanism of the synthesis of the 1,3;2,4-Dibenzylidene Sorbitol that catalyzed was probed afterwards. After the rate of mix was chosen as 450rpm and the reaction temperature as 70℃, the toluene-p-sulfonic acid was ascertained as the catalyst with the feed of the D-sorbitol and the benzaldehyde, four effective factors such as the benzaldehyde/sorbiol(B/S) feeding molar ratios, the reaction time, the dose of the cyclohexane and the mass of the toluene-p-sulfonic acid were investigated, which were used in the synthesis of the 1,3;2,4-Dibenzylidene Sorbitol. Then the orthogonal experimentation was used, several factors had different influence in yields, the sequence was that: the mass of the toluene-p-sulfonic acid > the reaction time, the dose of the cyclohexane> the benzaldehyde/sorbiol(B/S) feeding molar ratios. After the different experiment results at different factors were concluded, the following optimum condition was got: the benzaldehyde /sorbiol(B/S)feeding molar ratios is 2.2:1.0, the reaction time is 2h, the dose of the cyclohexane is 448%(weight percentage) and the mass of the toluene-p-sulfonic acid is 1% of the feed . The repeated experiments were taken at above factors, the yields we got were approximately 85%, the range of the melting points of the 1,3;2,4-Dibenzylidene Sorbitol was 217-222 °C, the purity of the product we knew was 93-97%.