Molecular diffusion and latex film formation: An analysis of direct nonradiative energy transfer experiments

Abstract

The diffusion of polymer molecules across an interface is an important topic in polymer physics. Measuring this diffusion process requires a labeling experiment so that the mixing of otherwise identical molecules can be followed. Here we examine the use of nonradiative energy transfer to follow the interdiffusion of polymer molecules during the annealing of latex films. Those films are prepared from a mixture of phenanthrene (Phe, the donor)- and anthracene(An, the acceptor)-labeled poly(butyl methacrylate) (PBMA) latex particles. We examine in some detail the kinetics of direct energy transfer (DET) at an interface and the evolution of the DET kinetics as the components mix. Time resolved and steady state measurement approaches are compared, and the former is employed to examine molecular diffusion in a series PBMA latex films. Various diffusion models are considered. Diffusion coefficients are calculated by treating the data in terms of a Fickian spherical diffusion model. A film from one set of samples is similar in molecular weight to that studied by small angle neutron scattering (SANS) [K. Hahn, G. Ley, H. Schuller, and R. Oberthur, Colloid Polym. Sci. 264, 1029 (1986)]. Diffusion coefficients calculated from both sets of experiments using similar Fickian diffusion models are very similar in magnitude.

Molecular Weight Effect on Latex Film Formation from Polystyrene Particles: A Photon Transmission Study

“…Alternatively, the process of interparticle polymer interdiffusion has been studied by direct nonradiative energy transfer (DET) using fluorescence decay measurements in conjunction with particles labeled with appropriate donor and acceptor chromophores (4 -7). This transient fluorescence technique has been used to examine latex film formation of 1-mdiameter hard poly(methyl methacrylate) (PMMA) (4) and 100-nm-diameter soft poly(butyl methacrylate) (PBMA) particles (5,6). These studies all indicate that in the particular systems examined, annealing the films above the glass transition temperature (T g ) leads to polymer interdiffusion at the particle-particle junction as the particle interface heals.…”

Fast Transient Fluorescence Technique (FTRF) for Studying Vapor-Induced Latex Film Formation

“…Alternatively, the process of interparticle polymer interdiffusion hsa been studied by direct nonradiative energy transfer (DET) using fluorescence decay measurements in conjunction with particles labeled with appropriate donor and acceptor 348 0021-9797/02 $35.00 chromophors (24)(25)(26). This transient fluorescence technique has been used to examine latex film formation of l-µm-diameter high-T g (PMMA) particles (24) and of 100-nm-diameter low-T g poly(butyl methacrylate) (PBMA) particles (25,26). Atomic force microscopy (AFM) has been used to observed the surface topography and packing of the PBMA system during stage II (27).…”

Interfacial and volumetric sensitivity of the dry sintering process of polymer colloidal crystals: a thermal transport and photonic bandgap study

“…transfer (DET), [32][33][34][35][36] small-angle X-ray scattering (SAXS), 21,[37][38][39][40] atomic force microscopy (AFM) 19,41,42 and solid state NMR 42,43 haven been established to investigate latex film formation and dry particle sintering. Most of these methods need a quite elaborate experimental setup or a specific labelling with dyes/ deuterated compounds of the sample.…”