The structure of LRS3 showed that the molar mass of GP-LRS3 and UP-LRS3 were mainly distributed in the range 1.0 104–2 104 g/mol and they accounted for 67.69% and 69.26% of total LRS3, while a decrease of MP-LRS3 was observed. The particle of MP-LRS3 was smaller and relatively smoother while UP-LRS3 was bigger and rougher compared to GP-LRS3 by ESEM