Effects of aging on latex film formation from polystyrene particles: A photon transmission study

Aging due to the storage time on latex film formation was studied using the photon transmission method. The UV visible technique was used to monitor t he evolution of transparency during film formation from two different polys tyrene (PS) particles produced by using two different steric stabilizers, i .e., polyvinyl alcohol and polyvinyl pyrrolidone. The latex films were prep ared from PS particles at room temperature before and after aging and annea led at elevated temperatures in various time intervals above glass transiti on (T-g). The increase in the transmitted photon intensity I-tr was attribu ted to the increase in the number of disappeared particle-particle interfac es. Relative decrease in transparency and delay in film formation were obse rved in the aged latex films compared to the nonaged ones. The Prager-Tirre ll model was employed to interpret the increase in crossing density at the junction surface. The back and forth activation energies (DeltaE) were meas ured and found to be dependent on aging for a diffusing polymer chain acros s the junction surface. (C) 2001 John Wiley & Sons, Inc.