Selective catalytic hydrogenation of styrene-isoprene-styrene block copolymer

Physical and chemical properties of styrene-isoprene-styrene block copolymer (SIS) can be improved by catalytic hydrogenation, which makes it more widely used in industry. Pt/g-C3N4 catalyst was prepared by a simple impregnation reduction method using chloroplatinic acid and urea as raw materials and then applied to heterogeneous catalytic hydrogenation of SIS. The structure of catalysts and products were characterized by XRD, TEM, 1HNMR and DSC. The effects of catalyst composition, loading amount of Pt and reaction conditions on the hydrogenation performance of SIS were investigated. The results showed that Pt/g-C3N4 exhibited good activity and selectivity, the hydrogenation degree of SIS and selectivity to C==C bonds of polyisoprene units were 85% and 95% under the conditions of cyclohexane as solvent, the dosage of SIS was 2.3-fold of the mass of catalyst, reaction temperature 140℃, 2 MPa and reaction time 2 h. © 2021, Editorial Office of FINE CHEMICALS. All right reserved.