Acetone-initiated photografting of methacrylic acid on low-density polyethylene film in water solvent

The effect of acetone on photografting of methacrylic acid (MAA) on low-density polyethylene (PE) film (thickness=30 μm) was investigated at 60°C in water solvent. A maximum percentage of grafting was afforded at a certain concentration of acetone, while the percentage of homopolymer decreased with increasing the acetone concentration (3–40 vol%). The total conversion in the system also decreased with an increase in the acetone concentration. The graft efficiency was less than 35%, showing an easier formation of homopolymer. These results suggest that acetone in the system acts as a photoinitiator as well as a screening agent. The resulting MAA-grafted PE film was characterized by a homogeneous distribution of the grafted chains, which was measured by an attenuated reflection infrared spectroscopy and an electron probe microanalysis, and higher pH-responsive character compared to that prepared by photografting using xanthone photoinitiator, which had been coated on the film sample earlier.