A New Method for Synthesis of Poly(2,6-dimethyl-1,4-phenylene oxide) and Poly(2,6-diphenyl-1,4-phenyl oxide)

Naser M Al Andis

doi:10.1155/2013/856928

Abstract

The polymerization of two monomers 2,6-dimethylphenol and 2,6-diphenylphenol was carried out by an oxidative route in the presence of Cu(I) as a catalyst and amine complex as a solvent assisted by microwave heating. The synthesized polymers were characterized by NMR spectroscopy, differential scanning calorimetry (DSC), and gel permeation chromatography (GPC). It was observed that this process of polymerization gives high yield (98 wt%) of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) and poly(2,6-diphenyl-1,4-phenylene oxide) (PPPO) with a molar mass of 1180 (M¯n), 1400 (M¯w) and 28000 (M¯n), 46500 (M¯w) gm/mol, respectively. A negligible amount of diphenoquinone was also observed and its dispersity was rather moderate, 1.17 and 1.68, respectively.

Highlights

Microwave-assisted reaction was introduced in 1986 [1]
Characterization. 13C and 1H NMR spectra of the PPO and PPPO in deuterated chloroform were recorded with a JEOL ECLIPSE 400 spectrometer, using tetramethylsilane (TMS) as an internal standard. e glass transition temperature (Tg) of PPO and PPPO was measured with a differential scanning calorimetry (DSC) (Shimadzu DSC 60), previously calibrated with indium. e samples were heated from 30 to 240∘C at a heating rate of 20∘C min−1. e dispersity of PPO and PPPO was determined at 30∘C with a Viscotek Complete Tetra Detector Platform and GPCMax front-end chromatography setup equipped with 2 × 1-MBMMW column by using standard polystyrene and tetrahydrofuran (THF) as a solvent
A maximum of 98 wt % conversion was obtained for PPO and PPPO a er 3 min of the reaction time with a negligible amount of diphenoquinone

Summary

Introduction

Microwave-assisted reaction was introduced in 1986 [1]. A high molar mass linear PPO was formed along with a small amount of diphenoquinone [13]. In this investigation it was observed that the length of the polymer chain depended on the amine type used, its molar ratio, and polarity of the solvent. According to Hasy works [14] in a similar reaction, it was noted that the diphenoquinone became its major product at a high temperature. In this work PPO and PPPO were synthesized for the rst time by oxidative polymerization using the Cu(I) in amine complex as catalyst, heating by microwave

Experimental

Results and Discussion

Conclusion