Free radical grafting of maleic anhydride in vapour phase on polypropylenefilm

The formation of a graft polymer is observed when polypropylene as a film r eacts with maleic anhydride in the vapour phase in the presence of peroxide . The activity of the employed peroxides decreases in the order: dicumylper oxide > bis(tert, butylperoxyisopropyl)benzene > benzoylperoxide, The graft ing reaction is not limited to the surface, but also takes place inside the film. Besides this reaction takes place on the film surface the formation of groups which give in ATR spectra a diffuse absortion band in the range b etween 1664 and 1500 cm(-1). The modified film is characterised by a wettin g tension of 35 dynes/cm and exhibits the anhydride group characteristic pr operties. (C) 1999 Elsevier Science Ltd. All rights reserved.