ma021197d_si_001.pdf (122 kB)
Facile Synthesis of ABC and CBABC Multiblock Copolymers of Styrene, tert-Butyl Acrylate, and Methyl Methacrylate via Room Temperature ATRP of MMA
journal contribution
posted on 2003-01-30, 00:00 authored by A. Ramakrishnan, R. DhamodharanA detailed investigation of the atom transfer radical polymerization of methyl methacrylate
(MMA) with the ethyl 2-bromoisobutyrate (2-EiBBr)/CuBr/N,N,N‘,N‘,N‘ ‘-pentamethyldiethylenetriamine
(PMDETA) catalyst system in anisole was performed at 30 °C. The number-average molecular weight of
the PMMA was observed to increase gradually and linearly while the polydispersity index (PDI) remained
narrow throughout the reaction time. The summary of these studies showed that PMMA with molecular
weight up to 105 g/mol could be synthesized in a controlled fashion at room temperature. The new route
developed was utilized to demonstrate the facile synthesis of ABC and CBABC multiblock copolymers of
styrene, tert-butyl acrylate (tBA), and MMA. For this, the starting blocks of AB and BAB were synthesized
by coupling different ATRP methods reported. The end-block consisting of PMMA was synthesized by
the ATRP of MMA using the CuCl/PMDETA catalyst system (halogen exchange) with anisole as the
solvent at room temperature. Gel permeation chromatography (GPC) was used to determine the Mn, Mw,
and PDI of the polymers synthesized. The PDI of all the block copolymers is found to be low (1.1−1.4).
1H NMR spectroscopy was used to determine the chemical composition of the block copolymers. Additional
evidence for the blocky nature was also gained from FT-IR and thermal analysis.