Microwave‐Assisted Ring‐Opening Polymerization of ε‐Caprolactone in the Presence of Ionic Liquid

Abstract

Summary: Microwave‐assisted ring‐opening polymerization of ε‐caprolactone in the presence of 1‐butyl‐3‐methylimidazolium tetrafluoroborate ionic liquid using zinc oxide as a catalyst is investigated. By adding 30 wt.‐% ionic liquid, poly(ε‐caprolactone) with a weight‐average molar mass of 28 500 g · mol−1 is obtained at 85 W for 30 min. The results indicate that the polymerization could be efficiently enhanced in the presence of ionic liquids under microwave irradiation because ionic liquids can effectively absorb microwave energy. magnified image

Synthesis and processing of biodegradable and bio-based polymers by microwave irradiation

“…The 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid has been successfully used as solvent for the ROP of ε-caprolactone: on account of its efficient microwave energy absorption. PCL with M w of 28,500 g/mol was obtained by means of a multimodal domestic oven at 85 W for 30 min, using Zinc oxide as catalyst (Liao et al, 2006). A large scale synthesis was recently performed using up to 2.45 Kg of monomer to assess the industrialization possibilities of microwave assisted ε-CL polymerization.…”

Applying the Principles of Green Chemistry to Polymer Production Technology

“…In addition, they have the ability to interact through hydrogen bonding, and dipolar and electrostatic interactions . Their highly ionic character improves the reaction rates in various reactions such as microwave‐assisted organic synthesis and polymerizations …”

“…Another major advantage of using ILs is the absence of enzyme deactivation, which usually takes place in most polar solvents (e.g., methanol) . Free‐radical polymerizations were also performed in ILs and interestingly, the molecular weights and rates of reactions were reported to be higher compared to that in organic solvents . The rate constants of propagation tend to be higher and the rates of termination lower than in bulk or conventional solution polymerization.…”

A study of the ionic liquid mediated microwave heating for the synthesis of new thermally stable and optically active aromatic polyamides under green procedure

“…26 Recently several organic reactions as well as macromolecular synthesis have been carried out using of this useful approach (combination of ILs and microwave irradiation). [27][28][29][30] Polyamides (PAs) are a class of engineering thermoplastics that play an important role in modern industrial and commercial applications. One of the drawbacks to the employment of these polymers is the difficulty in processing due to their insoluble nature in organic solvents in addition to their high melting and/or glass transition temperatures.…”