| 초록 |
Solid catalysts based on mesoporous silica materials modified with n-propylsulfonic acid were synthesized for cationic ring opening polymerization of octamethylcyclotetrasiloxane. Two sets with different pore sizes of MCM-41 (2.4 and 3.3 nm) and SBA-15 (8.1 and 12.0 nm) were used and denoted CASM, CAM, CAS, and CALS, respectively. The catalysts are environmentally friendly and can avoid using organic solvent. The conversion rate of the polymerization reactions were depending on the pore size of the mesoporous silica. The order of the rate was CAS (SBET = 850 m2/g) > CAM (800)> CASM (450). Results of CALS will be on the poster and the dependency of specific surface will be examined. The structures of the PDMS products were characterized by 1H-NMR and their molecular weights and polydispersities were investigated by gel permeation chromatography. |
