Classical cationic polymerization of styrene in a spinning disc reactor using silica‐supported BF₃ catalyst

Abstract

ABSTRACT:The carbo-cationic polymerization of styrene has been studied in a Spinning Disc Reactor (SDR) and the results were compared to those observed in a conventional Stirred Tank Reactor (STR). Addition of styrene to a slurry of silica-supported boron trifluoride (BF 3 /SiO 2 ) in 1,2-dichloroethane led to uncontrollable reactions in the STR at monomer concentrations Ͼ 25%w/w and initial temperatures of 20 -25°C. By comparison, monomer concentrations of 75% w/w were safely and controllably polymerized in the SDR at 40°C to yield polymers with molecular weights comparable to those reported in the literature for polymer prepared at Ϫ60°C. Exceptional heat transfer rates achieved in the SDR are sufficient to deal with the heat evolved when styrene is polymerized at concentrations as high as 75% w/w, the reaction proceeding under essentially isothermal conditions. In the present study, the effects of monomer/solvent feed rates, monomer concentrations, disc size, and disc speed on monomer conversions, polymer molecular weights, and polydispersities achieved in the SDR are investigated. Speculative explanations of the observed results are presented in terms of enhanced mixing effects on the polymerization mechanisms in the SDR.

Optimising a vortex fluidic device for controlling chemical reactivity and selectivity

“…Microfluidics also encompasses dynamic fluidic thin films generated centrifugally by passing liquids over rotating surfaces, as in spinning disc processors (SDPs)3456789101112131415161718 and horizontally aligned rotating tube processors (RTPs) with open ends18192021222324. These processors are effective in controlling chemical reactions34567891011121322, probing the structure of self organised systems14, and exfoliation and scrolling of graphite and hexagonal boron nitride ( h -BN)318192021222324. However, the volumes of liquid required for maintaining constant shear intensity in the fluids flowing over the rotating surfaces, coupled with finite residence times and high cost of construction, can limit the scope of their applications.…”

Novel acid initiators for the rapid cationic polymerization of styrene in room temperature ionic liquids

“…There have been recent reports, involving different Lewis acids, salts and solvents to stabilize the carbocation, to reduce side reactions and produce living polymers [6,7]. Studies pertaining to controlled polymerization of vinyl monomers at different temperatures in conventional solvents have also been investigated [8][9][10]. However, the handling and disposal of the conventional Lewis acid initiators and the chlorinated solvents used remains an issue [11,12].…”

Process Intensification on Synthesis of Nanoparticles in a Spinning Disc Reactor

“…In diesen Arbeiten wurde der Spinning-Disc-Reaktor für eine Vielzahl von Reaktionen, wie beispielsweise organische Synthesen [3,4], Polymerisationen [5,6], katalytische [7] und photokatalytische Reaktionen [8,9] und Fällungsreaktionen [10,11] eingesetzt. Ein modifiziertes Rotor-Stator-Reaktorsystem wurde von der Gruppe um Schouten für mehrphasige Reaktionssysteme entwickelt und getestet [12 -15].…”