Preparation and characterization of poly(2-hydroxyethyl methacrylate) grafted bacterial cellulose using atom transfer radical polymerization

The purpose of this study is to synthesize grafted Bacterial Cellulose (BC) nanofibers using Atom Transfer Radical Polymerization (ATRP) reinforced into poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogel matrix. Nanofibers grafting polymerizations were conducted in the presence of the catalyst CuCl/CuBr and the initiator 2-bromoisobutyrylbromide (2-BiBr). Degrees of substitution (DS) of BC-macroinitiators were quantified using both elemental analysis and gravimetric method. FTIR results confirmed BC nanofibers’ surface modifications of both initiator and hydroxyethyl methacrylate (HEMA) grafts. X-ray spectroscopy further confirmed the increase in carbonyl content after PHEMA-grafting polymerization. Results of the gravimetric analysis showed an increase in the weight of the grafted BC upon increasing reaction time. Furthermore, the change in the swelling ratio percentages of the reinforced composites product (BC-MI-3-g-PHEMA-1.5) was considerably higher based on reaction time. Slight increase in the swelling ratio of BC-MI-3 nanofibers was observed after 48 hours to reach 31 %. Moreover, results of thermal gravimetric analysis (TGA) demonstrated that decomposition temperature at 50 % weight loss (T50) decreased to 350 °C for BC-MI-3-g-PHEMA-1.5. These characteristics demonstrate potentials for applications in the biomedical fields including drug delivery and wound care.