Copolymerization of 4-Acetylphenyl Methacrylate with Ethyl Methacrylate: Synthesis, Characterization, Monomer Reactivity Ratios, and Thermal Properties

Gamze Barim,Mustafa Gokhun Yayla

doi:10.1155/2014/643789

Abstract

Methacrylates have high glass transition temperature (Tg) values and high thermal stability. A new methacrylate copolymer, poly(4-acetylphenyl methacrylate-co-ethyl methacrylate) (APMA-co-EMA), was synthesized. The thermal behaviors of copolymers were investigated by differential scanning calorimetry and thermogravimetric analysis. They behaved as new single polymers with singleTg’s and the thermal stability of the copolymers increased with increasing 4-acetylphenyl methacrylate (APMA) fraction, leading to the manufacture of copolymers with desiredTgvalues. Structure and composition of copolymers for a wide range of monomer feed ratios were determined by Fourier transform infrared (FT-IR) and1H-nuclear magnetic resonance (1H-NMR) spectroscopic techniques. Copolymerization reactions were continued up to 40% conversions. The monomer reactivity ratios for copolymer system were determined by the Kelen-Tüdös (ra(APMA)=0.81;rb(EMA)=0.61) and extended Kelen-Tüdös (ra=0.77;rb=0.54) methods and a nonlinear least squares (ra=0.74;rb=0.49) method.

Highlights

In recent years, many studies have been carried on aromatic acrylate and methacrylate monomers and polymers [1,2,3,4]
The mole fraction of acetylphenyl methacrylate (APMA) in copolymer was determined by measuring the integrated peak areas of the aromatic protons of APMA at 8.00 ppm, which is adjacent to the carbonyl and OCH2 protons of ethyl methacrylate (EMA) at 4.06 ppm
As the monomer reactivity ratios found by the three methods are close, the curves are similar and results differ from experiment to experiment, overall nonlinear least squares (NLLS) results give the best fit

Summary

Introduction

Many studies have been carried on aromatic acrylate and methacrylate monomers and polymers [1,2,3,4]. There are studies related to the synthesis and reactivity ratios of copolymers of APMA with glycidyl methacrylate [30]. All these studies were low conversion investigations. Are no moderate or high conversion investigations related to determining reactivity ratios of APMA-co-EMA system. For this reason, in this study the synthesis and characterization of copolymers of APMA with EMA are investigated at moderate conversion. Tg’s of new copolymers and the effect of APMA content on the thermal properties of resulting copolymers are investigated

Experimental

Results and Discussion

C OC O b b a a bC O a CH3

Conclusions