Methyl Methacrylate Polymerization in Nanoporous Matrix

摘要

The effect of nanoconfinement on methyl methacrylate (MMA) polymerization has been previously investigated. The results generally show that the number molecular weight (Mn) increases and PDI decreases for MMA polymerized under nanoconfinement (1-5). However, the PMMA reaction rate inside nanopores has not previsouly been experimentally examined although recent modeling (6) indicates nanoconfinement should result in increasing molecular weight, decreasing PDI, and accelerated reaction rate. The goal of this experimental work is to establish the validity or lack thereof of the modeling results. N anoporous controlled pore glass (CPG) is used as a nanoconfining matrix for MMA polymerization with pore diameters of 13 nm, 50 nm, and 110 cm. Both hydrophilic native surfaces and hydrophobic silanized CPGs are employed. The reaction is followed by measuring heat flow as a function of reaction time during isothermal polymerization at temperatures ranging from 60 °C to 95 °C using Differential Scanning Calorimetry (DSC).