244 Radiation‐Processing of Polymers for Advanced Micro‐ and Nanostructured Materials

16:15 - 16:35 Tuesday 23 September | Advanced Materials 3: Medical & Speciality
Giovanni Marletta, FRSC: Department of Chemical Sciences, University of Catania, Viale Andrea Doria, 6I‐95125 Catania, Italy
E‐Mail: gmarletta@unict.it

Abstract
The need for having a breakthrough in fields relevant to health and safety like biocompatible materials, bioelectronics devices, biosensors etc., is the driving force to develop new performant methods for the controlled modification of surfaces and bulk of materials. In particular, polymers represent the material of choice for most of the desired biological applications, due to their highly specific properties, including the dynamical behaviour in presence of external stimuli and the biomimetic mechanical properties.

A welt of competing methods is currently used to modify variable materials thicknesses at the surfaces of inorganic or polymeric materials. Roughly, we can distinguish three basic areas, respectively consisting in "wet chemistry" approach to attach specific functional group onto materials surfaces, deposition of thin and ultrathin films at the materials surfaces and radiation‐based methods to modify the chemical and physical structure of the materials of interest.

Radiation processing has recently shown an intrinsic capability to produce micro‐ and nano‐sized materials or nano‐sized modifications in various materials, which as a result of their size display completely different properties from bulk materials. This capability and the versatility of the radiation based methodologies are the key to induce real breakthrough in critical areas of advanced micro‐ and nano‐structured materials, as biomaterial engineering, polymeric scaffolds for tissue engineering, radiation synthesis of new polymeric phases, fabrication of micro‐ and nanoscale composites, drug delivery polymers, innovative membranes for sensing, diagnostics and imaging, smart polymers, etc. Indeed, the radiation‐induced processing may be considered as the election methods to enable advanced materials engineering at the nanoscale, "implanting" specific functionalities on the polymer surfaces, improving their biocompatibility, enhancing interfacial adhesion with heterogeneous materials, modifying their mechanical and electrical properties, promoting fast and cost effective materials processing.

Among the various irradiation‐based technologies, those involving electron and ion beams are particularly relevant in view of the intrinsic nanometric scale of the induced processes, the relevant dimensions ranging between tens of nanometers up to tens of micrometers.

The present lecture will discuss both fundamental and applied aspects of the use of radiations to obtain micro‐ and nano‐structured materials.

As to the fundamental aspects, the relationship among irradiation parameters, including doses, type of radiation and nature of the primary events will be discussed in view of their intrinsic spatial scale for the different irradiation methodologies.

As to the applied aspects, the use of radiation processing to fabricate hybrid biological systems, for aerospace applications, temperature‐responsive polymers to fabricate transplantable cell sheets, new generation hydrogel biomaterials, radiolytic syntheses of nanoparticles for sensing and biological imaging will be described for very different polymers as polystyrene, segmented polyurethane, polyethylene, polysiloxane, polyimide.