Interaction of Energetic Heavy Ions with Polymers

The effects of electronic excitations due to irradiation of electrons or energetic heavy ion (\u3e1 MeV/amu) irradiations on Linear polymers of general formula -(CR1R2-CR3R4)n- are reviewed and compared with previous results obtained with γ and electron irradiation. The polymer modification are discussed accounting for the nature and the position of the R1, R2, R3 and R4 substituents on the main chain. It is suggested that Linear polymers evolve according to the R can nature (R=R1, R2, R3, R4). This paper includes the physical and chemical processes of electronic excitation and the mechanisms which Lead to modification of the macromolecules. An attempt is made to relate the macromolecular structure of polymers and their structural modifications under irradiation

Glow Discharge Effects on Polytetrafluoroethylene Polymers Investigated by Secondary Electron Microscopy and X-Ray Photoelectron Spectroscopy

A glow discharge treatment of Polytetrafluoroethylene avoids charging effects and permits observation of the sample in Scanning Electron Spectroscopy; x-ray Photoelectron Spectroscopy has been used to study changes in the surface chemical composition and electronic structure of the polymer produced by this treatment

New sulfonated pyrrole and pyrrole 3-carboxylic acid copolymers membranes via track-etched templates

New copolymers of polypyrrole and poly(3-carboxylic acid pyrrole) have been synthesized via diaphragmatic method using track-etched polycarbonate matrix. The carboxylic acid presence permits to introduce new functionalities such as sulfonate groups. The resulted copolymer membranes with tubules microstructure has been characterized by Scanning Electron Microscopy, X-ray Photoelectron Spectroscopy, Time-of-flight Secondary Ion mass Spectrometry and FTIR. By SEM it was observed that ion-track trajectories present characteristic of crossing. FTIR, XPS and ToF-SIMS proved the attachment of the Taurin molecule to the membrane. The thermal stability study shows that the polypyrrole copolymer membranes have an exceptional stability; decomposition was not observed up to 900°C

A study on radiation grafting of methyl methacrylate induced by swift heavy ions in poly(vinylidene fluoride)

Poly(vinylidene fluoride) films were irradiated with swift heavy ions to induce the formation of reactive radicals which are able to initiate a grafting reaction with methyl methacrylate. We have studied the influence of irradiation parameters such as mean absorbed dose, type of ion, electronic stopping power of the ion on the grafting yield and rate. The influence of an inhibitor is shown and a comparison of grafting results between two crystalline phases of the poly(vinylidene fluoride) is established

Study of the molecular weight distribution of polystyrene grafted by means of swift heavy ions

Thin poly(vinylidene fluoride) films were irradiated with swift heavy ions in order to induce along the ion path the formation of radicals which can initiate the grafting of styrene. Using size exclusion chromatography, we have studied the influence of irradiation (dose, type of ion) and kinetic (grafting time, monomer concentration) parameters on the molecular weight distribution ([math], P) These parameters modify the length and the polydispersity of the polystyrene grafted chains. An effect of the electronic stopping power of the ion is observed

A FTIR characterization of a haemocompatible material obtained by swift heavy ion radiation grafting

In order to prepare materials destined to be used as vascular prothesis, a radiation grafting of styrene, induced by swift heavy ions in polyvinylidene fluoride films, was performed. A substitution of the grafted polystyrene with sulfonate and aspartic acid sulfamide groups, which confers to the polymer anticoagulant properties, was achieved. The material was characterized by Fourier Transform Infrared spectroscopy at each step of the synthesis

ESR studies in γ‐irradiated and PS‐radiation‐grafted poly(vinylidene fluoride)

International audienceAbstract The fluoropolymer poly(vinylidene fluoride) was irradiated with γ rays to induce a polystyrene (PS) radiation grafting via an indirect method. Electron spin resonance and Fourier transform infrared studies were performed to identify the species that initiated the PS grafting. Specific experiments were performed to prove separately the importance of each kind of radical. A localization of the radicals in this irradiated polymer is proposed, and a kinetic model of the grafting is given. © 2001 John Wiley & Sons, Inc. J Polym Sci B Part B: Polym Phys 39: 1437–1448, 200