Evaluation of the effective parameters in the grafting of functional monomers on the surface of polypropylene hollow microfibers by peroxidation and mutual gamma irradiation methods

Abstract

One of the most efficient methods for modifying the surface of polymers for some specific applications such as the production of adsorbents is the grafting of functional monomers onto polymers. In this research, the grafting of acrylonitrile and methacrylic acid on the surface of polypropylene hollow microfibers and its effective parameters such as radiation doses and concentration of functional monomers were investigated using peroxidation and mutual gamma irradiation methods. The highest rate of grafting was 81.2% which was related to the mutual irradiation method with 45 kGy radiation dose, which was carried out in the monomer concentration of 40% and in the presence of ferric chloride inhibiting salt with a concentration of 0.2%. The use of Mohr’s salt in the mutual method had a lesser effect in preventing the side reaction of polymerization due to its low solubility in the organic medium. The highest rate of grafting using 0.2% Mohr’s salt at 40 kGy irradiation dose was 33.62%. Infrared spectroscopy of the grafted samples confirmed the results obtained by calculating the grafting percentages by the gravimetric method. In addition, the results showed that the peroxidation method performed at the Atomic Energy Organization's gamma radiation center was not effective.

Keywords

• surface modification
• hollow microfibers
• mutual grafting
• peroxidation
• mohr’s salt
• ferric chloride