Strength development at the interface of amorphous polymers and their miscible blends, below the glass transition temperature

Bonding amorphous polystyrene (PS) and poly(2,6-dimethyl 1,4-phenylene oxide) (PPO) has been carried out in a broad range of temperatures and contact; times (t), but always below the glass transition temperature (T-g), in a lap-shear joint; geometry. Strength at the symmetric and asymmetric polymer/polymer interfaces develops with t(1/4) and, hence, is diffusion controlled. The development of strength at the homopolymer/miscible blend interface below T-g can be simulated from data for homopolymer/homopolymer interfaces, taking into account the wetting (and "fast diffusion") and diffusion contributions to the development of strength.