Frank R. Libsch, Takatoshi Tsujimura
Active Matrix Liquid Crystal Displays Technology and Applications 1997
Normally brittle, high molecular weight polystyrene can be very effectively toughened by blending polybutadiene of 2.76 kg/mol at volume concentrations of a few percent. An increase of toughness by about a factor of 10 above that of homo-PS can be readily achieved with a 1.1% PB-2.76K blend if the precipitated PB pools can be maintained at a size smaller than 0.2 μm. It is proposed that this dramatic effect is the result of a controlled solvent crazing action of the PB-2.76K on the homo-PS when the former becomes soluble into the latter in the fringing layers of the craze borders subjected to negative pressure by the local craze tuft drawing process. © 1990, American Chemical Society. All rights reserved.