Accession Number : ADA305782

Title :   Environmental Stress Cracking of Polymers.

Descriptive Note : Final rept.,

Corporate Author : UNIVERSITY OF SOUTHERN COLORADO PUEBLO

Personal Author(s) : Hahan, Kent I.

PDF Url : ADA305782

Report Date : 1980

Pagination or Media Count : 102

Abstract : A two point bending method for use in studying the environmental stress cracking and crazing phenomena is described and demonstrated for a variety of polymer/solvent systems. Critical strain values obtained from these curves are reported for various polymer/solvent systems including a considerable number of systems for which critical strain values have not been previously reported. Polymers studied using this technique include polycarbonate (PC), ABS, high impact styrene (HIS), polyphenylene oxide (PPO), and polymethyl methacrylate (PMMA). Critical strain values obtained using this method compared favorably with available existing data. The major advantage of the technique is the ability to obtain time vs. strain curves over a short period of time. This allows, in most cases, sensitive determination of the nature of the transition between the time independent portion and the time dependent portion of the time vs. strain curve. The data obtained suggests that over a short period of time the transition in most of the polymer solvent systems is more gradual than previously believed. Studies of the temperature effects in the PC/MIBK, PC/Cyclohexanone, and PPO/MIBK systems give results consistent with previous studies that support a plasticization mechanism for environmental stress cracking and crazing. (MM)

Descriptors :   *POLYMERS, *CRACKING(FRACTURING), *PLASTICS, STYRENES, POLYMETHYL METHACRYLATE, STRAIN(MECHANICS), GLASS, BENDING, STRENGTH(MECHANICS), STRAIN RATE, SOLVENTS, POLYCARBONATES, PLASTICIZERS, POLYPHENYLENES, CYCLOHEXANONES, CRAZING.

Subject Categories : Polymer Chemistry
      Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE