Producing bimodal molecular weight distribution polymers through facile one‐pot/one‐step RAFT polymerization

Abstract

Well‐defined bimodal molecular weight distribution (MWD) polystyrene and polystyrene‐b‐poly(acrylonitrile) were successfully synthesized using a pair of mono/difunctional trithiocarbonate RAFT agents 1 and 2 via one‐pot RAFT polymerization. The kinetics of RAFT polymerization for styrene in bulk with a molar ratio of [St]0:[AIBN]0:[1]0:[2]0 = 1200:1:2.5:2.5 was studied at 75°C. The results indicated that the system showed excellent controllability and “living” characteristics to both higher and lower molecular weight fractions, providing an efficient and facile way to producing bimodal MWD (co)polymers with both controlled molecular weight (MW) and MWD in molecular level, and the plausible mechanism was discussed in this work. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Exploiting the Interplay Between Bi-Modal Molecular Weight Distribution in Polystyrene and Humidity to Induce Self-Assembly of Biomimetic Micropillars/honeycomb Morphology in Thin Polymer Film

“…(27) Thus, it should be highlighted that the location and the width of the MWD can affect polymer solution properties and, as a result, solid thin polymeric films formation. The width of the MWD can be tailored either within the polymerization process (28,29) or by mixing two polymer species with very narrow MWD (30). By tailoring the concentration and location of the two nodes of the distribution of a bimodal polymer, it is possible achieve properties that are otherwise unavailable.…”

Water vapor induced self-assembly of islands/honeycomb structure by secondary phase separation in polystyrene solution with bimodal molecular weight distribution

“…As a result, a porous membrane with higher robustness was obtained. (26) The width of the MWD can be tailored either within the polymerization process (27,28) or by mixing two polymer species with a very narrow MWD (29). Heitmiller et al reported that a heterogeneous melt of polyethylene had a higher flow index than a homogeneous melt.…”

Mechanochemical tuning of molecular weight distribution of styrene homopolymers as postpolymerization modification in solvent‐free solid‐state

“…[ 1–3,7–9 ] Methods to control MWD are generally based on the manipulation of specific variables during the polymer synthesis or performed using melt or solution blending of different MWDs. [ 8–14 ]…”