Question

For polymerization of styrene in tetrahydrofuran at 25°C using sodium naphthalide initiator, the rate coefficient for propagation is 550 dm^3 mol^-1 s^-1. If the initial mass concentration of styrene is 156 g dm^-3 and that of sodium naphthalide is 3.02x10^-2 g dm^-3, calculate the initial rate of polymerization and, for complete converison of the styrene, the number-average molar mass of polystyrene formed. Comment upon the expected value of molar mass dispersity (Mw/Mn) and the stereoregularity of the polystyrene produced.

Assume: Process is anionic polymerization, Styrene MW=104g/mol, Sodium Naphthalide MW=151g/mol, and initiation occurs by dissociation mechanism

Answer 1

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