Effects of compositional parameters on morphology and rheological properties of HDPE/PVA blends

• Published in: Journal of applied polymer science 2023-06, Vol.140 (21), p.n/a
• Main Authors: Melo Carvalho, Benjamim, Silva, Jorge Manuel Jardim, Farah, Marcelo, Kaipers Stocker, Mariele, Lauer Sanson, Murilo
• Format: Article
• Language: English
• Subjects: Compatibilizers; Crosslinking; dynamic mechanical analysis; electron microscopy; Glass transition temperature; High density polyethylenes; Hydrogen bonds; Maleic anhydride; Materials science; Morphology; Parameters; poly(vinyl alcohol); polyethylene; Polymer blends; Polymers; Polyvinyl alcohol; Rheological properties; Rheology; selectively crosslinked blend; Thermoplastic resins; Viscosity
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.53869

Polymeric blends are relevant for research and industry because of their versatility, being able to accomplish property tailoring with competitive cost and ease to scale up, when compared to the development of in‐reactor new polymers. Blends of thermoplastics, however, might have their morphology and properties altered upon processing, therefore, there is uncertainty to some outputs after melt processing. Therefore, having a fixed morphology that is capable of being further processed without significant changes have industrial and academic value. This work presents a comprehensive study of rheological properties and morphology of a selectively crosslinked blend of polyethylene (HDPE) and poly(vinyl alcohol) (PVA), where the effect of the following parameters are evaluated: dispersed phase (PVA) weight fraction, continuous phase (HDPE) rheological properties, compatibilizer (PE‐g‐MAh) and crosslinking agent (maleic anhydride) content. Overall, melt complex viscosity and elasticity have increased with PVA weight fraction and HDPE viscosity. The compatibilizer content has not severely affected melt rheology, although it influenced blend morphology. Crosslinking agent content affected melt rheology and glass transition temperature in a complex way due to the probable competition of some phenomena (crosslinking and reaction vs reduction of crystallinity degree and H bond attenuation), with little effect over PVA morphology. In this selectively crosslinked blend, PVA weight fraction leads to an increase in melt viscosity and elasticity. The HDPE viscosity affects blend morphology and rheological properties. The compatibilizer (PE‐g‐MAh) content does not severely affect blend rheology, but it affects its morphology. PVA crosslinking agent (MAh) loading level affects glass transition temperature of PVA, and slightly affects blend rheology and PVA morphology.