Environmental stress cracking (ESC) is a premature failure of a polymer exposed to a fluid, under stress which is much less than its yield stress. Many experimental works were done before in an effort to predict experimentally the ESC potential of a fluid in different polymers. None of the previous works applied molecular modeling techniques to predict this potential so this work is a pioneering work. This study's goal was to apply atomistic molecular modeling techniques to gain a better understanding of the ESC mechanism and to predict the ESC potential of different fluids in polymers. Our model experimental system was amorphous polycarbonate (PC) with water as an ESC fluid. The computational study was expanded to include a high level ESC fluid for PC-toluene and a non ESC fluid-BD, together with the moderate ESC fluid-water. A clear distinction between ESC fluids and non ESC fluids for PC was achieved by means of molecular modeling. The experimental work approved that water is an ESC fluid for PC as predicted in the computational part.

Plastic components in use are often exposed to a large number of influences which strongly affect the functionality of the component and are often the main cause of their failure. Here, the environmental stress cracking (ESC) is considered as the main cause for the failure of plastics. Until now, there are only a few possibilities on how to predict the ESC resistance of a plastics component in use and the engineer is often confronted with this failure after the product development process is already completed. This investigations deal with that problem and it is shown how the stress cracking resistance of plastics can be influenced according to the already completed product development by the example of polycarbonate under the influence of water. The focus is on the targeted influencing of the internal part properties, the influence of additional fiber reinforcement and as a last option the selection of a new material under the elimination of elaborate experiments using molecular dynamics simulations. POLYM. ENG. SCI., 59:E361–E366, 2019. © 2018 Society of Plastics Engineers

No abstract

No abstract