[6p-A409-1~8] 【CS.1】3.3 & 4.5 Code-sharing session

▲ [6p-A409-2] Diffusivity of single fluorescent probes embedded in thin polymer films

〇(M1)CHARMAINE SIBANDA SIBANDA¹, DR G BOSMAN BOSMAN¹, PROF E ROHWER ROHWER¹ (1.LRI, STELLENBOSCH UNI)

Keywords:thin polymer films

Photophysics and photochemistry in polymer science has been of central areas of interest in understanding the structure and dynamics of polymers. The physical properties of polymers especially the dynamical properties close to the phase transition from rubbery to the glassy state are complex and have not been completely understood despite experimental and theoretical studies over the past decades [1]. Understanding the dynamics of polymer nano environments is highly crucial for numerous technological applications in various industrial and biomedical sectors related to protective and functional coatings and biocompatibility of medical implants [2]. The diffusivity of single probes embedded in thin polymer films can exhibit unusual physical properties due to geometric constraints imposed by the presence of surfaces and interfaces and using single molecule fluorescence microscopy as an imaging technique, allows one to look at the microscopic processes on the nanometer scale [3]. For this research single nanoparticles were embedded in thin polystyrene (PS) and poly (isobutyl methacrylate) (PIMA) films and were used to study the nano scale polymer dynamics via the diffusivity of the single nanoparticles. The diffusivity of the single nanoparticles was analyzed assuming a typical Brownian motion model that is used to calculate the mean square displacement of the single probes as a function of time, which in turn uniquely determines the diffusion coefficient of the single probes. Using the diffusion coefficient of the single nanoparticles helps to study the molecular dynamics in thin polymeric films and how these molecular dynamics are related to the glass transition of the thin polymer films.