Damaging effect of admixtures used in crop protection products on high density polyethylene packaging material. (October 2022)

• Record Type: Journal Article
• Authors: Thuy, Maximilian; Niebergall, Ute; Oehler, Harald; Alig, Ingo; Böhning, Martin
• Is Part Of: Polymer testing. Volume 114(2022)
• Publication Date: 2022-10
• Subjects: Environmental stress cracking -- High-density polyethylene -- Crop protection products -- Full notch creep test -- Fracture surface analysis -- Crack opening displacement; Polymers -- Testing -- Periodicals; Polymères -- Tests -- Périodiques; 620.1920287
• DOI: 10.1016/j.polymertesting.2022.107672
• Languages: English
• ISSNs: 0142-9418

Abstract

Abstract: The phenomenon of environmental stress cracking is still a major issue in materials engineering as well as from a scientific perspective. Especially in the case of packaging materials made of high-density polyethylene, assessing the potential of premature damage due to environmental stress cracking is complex because of the large number of components in possible liquid filling goods. As a first guideline, the well-known effect of detergents and dispersants is usually considered, but the interplay with other components, such as organic solvents is often unknown. Particularly challenging in this respect are crop protection products, consisting of several different admixtures in addition to the biologically active ingredients. This study is based on two model liquids representing these admixtures that were established for testing in this context. The model liquids as well as their constituting components were used as liquid media in the Full Notch Creep Test to characterize the environmental stress cracking behavior of a typical high-density polyethylene. Complementary to the time-to failure of a notched specimen obtained from these tests, the crack opening was monitored optically, and the fracture surface was analyzed post-failure by laser scanning microscopy as well as scanning electron microscopy. Based on the results, the effect of various surfactants as well as the influence of organic solvents on environmental stress cracking are discussed. Graphical abstract: Image 1 Highlights: Environmental stress cracking behavior of PE in complex and binary liquid mixtures. Optical in-situ analysis of crack opening during Full Notch Creep Test. Undamaged actual cross-sectional area hinders and determines craze fail and rupture. Balance of crack growth and shear deformation determined by solvent plasticization. Transition to ductile deformation induced by plasticization at shifted yield stress.