Expanded polytetrafluoroethylene, ePTFE, is an attractive material for use as the implant in facial reconstruction surgery because it is bioinert; however, its low surface energy does not facilitate a strong interfacial bond with bone and thus for some applications the surfaces need to be modified to enhance their bone-integration properties. The surface modification of ePTFE membranes with copolymers of acrylic acid (AA) and itaconic acid (IA) using in situ gamma radiation induced grafting has been studied. Solutions with AA mole fractions ranging from 0.4 to 1.0 have been investigated. Graft yields of 35-50% with water uptakes of greater than 300% were obtained using 3 mol L 21 aqueous solutions of the monomers and a total incident dose of 10 kGy. The grafts were characterized by Fourier transform infrared and X-ray photoelectron spectroscopy analyses and the compositional microstructure of the grafted copolymers was investigated. The water uptake by the grafted membranes displayed a complex dependence on polymer chemistry and topology.

BACKGROUND: Copolymers of acrylic acid (AA) are important materials for the preparation of glass ionomer cements. Copolymerisation of AA is widely used to alter the acid strength of the material and to increase the number of salt bridges formed in cements. In this paper we report the copolymerisation of AA with n‐butyl vinyl ether (BVE) to form unique copolymers of the hemiacetal ester and with BVE incorporated into the main chain.RESULTS: AA and BVE undergo a spontaneous reaction to form a hemiacetal ester which can itself undergo free radical copolymerisation. The kinetics of this reaction in the bulk state have been examined. In addition, under these conditions BVE is incorporated into the polymer main chain via a free radical mechanism.CONCLUSION: Novel copolymers of the hemiacetal ester and BVE have been prepared in this study. The hemiacetal side chains are labile under moderate heating, being converted back to the acid analogue. Copyright © 2009 Society of Chemical Industry