Two new test methods for assessing environmental stress cracking of amorphous thermoplastics

Two new test methods, monotonic creep and micro-hardness, are used to study the environmental stress crack (ESC) resistance of polymethyl methacrylate (PMMA) and unplasticised polyvinyl chloride (UPVC). Monotonic creep is shown to discriminate, to a high resolution and in the short term, the ESC resistance of polymer/fluid pairs, including those polymer/fluid pairs which exhibit mild/weak interactions. Micro-hadness is shown to offer a cost-effective method of mass screening polymer/fluid pairs for compatibility.