REN Shenyong, ZHANG Ka, YAN Hui, et al. Grafting of organic polymer in pores of macroporous silica vesicle material[J]. CIESC Journal, 2016, (8): 3507-3514.
DOI:
REN Shenyong, ZHANG Ka, YAN Hui, et al. Grafting of organic polymer in pores of macroporous silica vesicle material[J]. CIESC Journal, 2016, (8): 3507-3514.DOI: 10.11949/j.issn.0438-1157.20160415.
Grafting of organic polymer in pores of macroporous silica vesicle material
Macroporous vesicle material with more than 100 nm diameter was synthesized via hydrothermal method using poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123) as template and tetramethyl orthosilicate (TMOS) as silica source. Moreover
the radical initiators with silane coupling groups such as (2-bromo-2-methylpropionyl)oxy-butyl triethoxysilane (BPE) and (2-bromo-2-methylpropionyl) oxy-butyl chlorodimethylsilane (BPCM) were synthesized by a two-step method. Then BPE and BPCM were grafted onto the inner surface of vesicle via coupling reaction of silane group and Si-OH. The elemental analysis confirmed that BPCM gave higher grafting efficiency. After that the atom transfer radical polymerizations (ATRP) of methyl methacrylate (MMA) and butyl methacrylate (BMA) were initiated in the pores of vesicle
respectively
and the monomers gradually reacted on surface-initiators to form polymer brushes. Transmission electron microscopy (TEM) results suggested that the vesicles retained after grafting of polymers into the inner surface of material successfully. The grafted polymers were cleaved by chemical process and analyzed by gel permeation chromatography (GPC). The number average molecular weights (Mn) of PMMA and PBMA were 7600 and 11400
respectively
the polydispersity indexes (PDI) of PMMA and PBMA were both 1.25.