This application note discusses the characteristics of block copolymers synthesized via transition metal mediated living radical polymerization. These reactions allow for controlled synthesis of polymers with predetermined molecular weight, polydispersity, and well-defined architecture using cheap and simple procedures. The ability to convert hydroxyl functional groups to active initiator groups enables the synthesis of architecturally diverse materials such as stars, blocks, and grafts. Block copolymers consist of two or more chains with different repeat units, known as blocks. For example, a block of polystyrene connected to a block of polymethy...
The document explains that determining the molecular weight of block copolymers is not straightforward when using conventional Gel Permeation Chromatography (GPC) with only a refractive index detector due to composition effects. It proposes using viscometry via a universal calibration approach, which relies on the relationship between molecular weight and molecular density.
The analysis covered a series of five poly(styrene-co-methyl methacrylate) copolymers manufactured with different molecular weights.
The analysis was performed using a flow rate of 1 mL/min.
The analysis was conducted at a temperature of 40°C.