and modified with silane coupling reagents vinyl triethoxylsilane (KH-151)
-glycidylpropyltrimethoxysilane (KH-560) and -methacryloxypropyl- trimethoxysilane (KH-570)
respectively.Then different types of modified mesoporous sieves (M-SBA-15) were used as microreactors which were loaded with methyl methacrylate and initiator in toluene.Mesoporous channels were covered by PMMA in the form of thin coating via solution polymerization.M-SBA-15
PMMA/M-SBA-15 composites and PMMA polymerized in the channels were characterized by X-Ray diffraction (XRD)
N2 adsorption/desorption
gel permeation chromatography (GPC)
1H-nuclear magnetism resonance spectrum (1H-NMR)
Fourier transform infrared spectra (FTIR)
thermal gravimetric analysis (TGA) and differential scanning calorimeter (DSC).The results showed that modified mesoporous sieves and parts of the composites still retained the basic features of order mesoporous materials.Compared with SBA-15
BET surface areas
pore size and pore volume of both the modified mesoporous sieves and corresponding polymer composites decreased obviously.This confirmed that PMMA was loaded into the mesoporous channels.Molecular weight of PMMA in the channels of the mesoporous sieves was ten times more than that of traditional PMMA via solution polymerization.In addition
thus prepared PMMA exhibited higher initial thermal temperature
and glass transition temperature (an increase of 9~11 K) due to the little weak bonds formation and higher molecular weight.Furthermore
KH-151 modified SBA-15 loaded the highest PMMA content
and the PMMA possessed the highest molecular weight and Tg.