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Synthesis of bio-polyols by epoxide ring opening reaction with H2O as a reagent

The effect of reaction parameters like the amount of reagents, catalyst, temperature and time of a polyol synthesis were studied through the hydroxyl and oxirane oxygen content of product. Moreover, the impact of the parameters on the correlation P/E was determined by comparing a hydroxyl group formation to an epoxide group consumption. When the hydroxylation reaction was carried out with ESO:H2O mole ratio of 1:15; in 8 wt.% H2SO4; at temperature of 70 oC and in 5 hours, the hydroxyl content of 358.51 mgKOH/g of the obtained product was achieved. | Vietnam Journal of Chemistry, International Edition, 55(4): 411-416, 2017 DOI: 10.15625/2525-2321.2017-00482 Synthesis of bio-polyols by epoxide ring opening reaction with H2O as a reagent Nguyen Thi Thuy*, Vu Minh Duc, Nguyen Thanh Liem Polymer Center, Hanoi University of Science and Technology Received 13 December 2016; Accepted for publication 28 August 2017 Abstract The different nucleophilic reagents have been using in epoxide ring opening reactions among which water is the most preferable. At first, the epoxide group must be protonated by water in the presence of H2SO4 as catalyst. The successful epoxide ring opening reaction of epoxidized soybean oil (ESO) by water in the H2SO4 environment was verified by FTIR and H-NMR spectroscopy. The effect of reaction parameters like the amount of reagents, catalyst, temperature and time of a polyol synthesis were studied through the hydroxyl and oxirane oxygen content of product. Moreover, the impact of the parameters on the correlation P/E was determined by comparing a hydroxyl group formation to an epoxide group consumption. When the hydroxylation reaction was carried out with ESO:H 2O mole ratio of 1:15; in 8 wt.% H2SO4; at temperature of 70 oC and in 5 hours, the hydroxyl content of 358.51 mgKOH/g of the obtained product was achieved. Keywords. Epoxidized vegetable oil, biopolyol, epoxide ring-opening, epoxidized soybean oil. 1. INTRODUCTION There are many methods to synthesize polyols from a epoxidized vegetable oil (EVO). These methods can be divided into two groups. Group 1 (indirect method) - polyols are synthesized from the epoxidized vegetable oil through the formation of intermediate compounds. This group has two methods: method 1-the epoxidized vegetable oils were first performed by ring-opening polymerization catalyst HBF4, then reduced by catalytic LiH4; method 2 – the epoxidized vegetable oil was initially carbonized by CO2 and catalyst, then ring opened by agent of HR forms such as HN[R'OH]2. Group .