Dodecyl Methacrylate Polymerization under Nanoconfinement: Reactivity and Resulting Properties
Qian Tian, Sara Orski, Sindee Simon
The effect of nanoconfinement on the free radical polymerization of dodecyl methacrylate (DMA) with di-tert-butyl peroxide (DtBP) initiator is investigated over a wide temperature range from 110 to 190 °C using differential scanning calorimetry. The reaction rate increases with increasing temperature, is Arrhenius at temperatures lower than 160 °C, and is highest in 50 nm pores and lowest in bulk conditions. Depropogation becomes increasingly pronounced at temperatures higher than 160 °C and results in the equilibrium conversion decreasing with increasing temperature as the ceiling temperature is approached. The equilibrium conversion is almost the same for samples reacted in bulk conditions and in 50 nm pores, but decreases in 8 nm pores at temperatures higher than 180 °C. For bulk polymerization, the molecular weight increases as temperature decreases with an infinite molecular weight, crosslinked product obtained at temperatures of 140 °C and lower due to chain transfer to polymer. At all polymerization temperatures, the molecular weight of polymer synthesized in nanopores is smaller compared to that synthesized in bulk conditions, and the molecular weight and polydispersity decreases as pore size decreases. Crosslinked products are not observed for the polymer synthesized under nanoconfinement, indicating that confinement suppress chain transfer to polymer. Nanoconfinement can be used as a synthesis tool to control the polymer properties.
, Orski, S.
and Simon, S.
Dodecyl Methacrylate Polymerization under Nanoconfinement: Reactivity and Resulting Properties, Macromolecules, [online], https://doi.org/10.1021/acs.macromol.1c01724, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932442
(Accessed June 8, 2023)