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Abstract Considering their simplicity, processibility, and tunable rheological properties, polymer composite‐type precursors hold exceptional promise in the processing of polymers, ceramics, metals, and their composites. This large variety of precursors used in many different applications cover a large compositional space with dramatically varying rheological properties. Understanding how precursor composition influences their rheological properties is a key need towards streamlining the design and implementation of these precursors. With regard to this design advancement, this study elucidates the composition‐rheology relationships of graphene‐poly(ethylene) oxide (PEO) composite inks as a sample polymer composite‐type precursor. To this end, shear and extensional rheology of numerous compositions were studied across a wide compositional space, which varied graphene concentration, total solid concentration, and binder molecular weight. These studies showed that composition greatly affected various rheological parameters, such as the overall presence of yielding behavior. Specifically, this study illustrated the influence of (i) binder structure, (ii) total solid loading, and (iii) binder‐filler interactions on ink rheology. Extensional rheology was studied to examine how relaxation behaviors were dependent on composition and explicate how relaxation behaviors coincide with responses to shear forces. In tandem, our results illuminate significant composition‐rheology relationships in polymer composite‐type precursors. HighlightsRheology of polyethylene oxide‐graphene composite precursors were studied.Shear and extensional rheology, and their correlations were investigated.Composition‐binder molecular weight‐yielding relationships were elucidated.Extensional relaxation regimes were identified with respect to composition.Results can be used to determine compositional ranges for different processes.
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This content will become publicly available on December 20, 2025
Impact of salt and fillers on the rheological properties of polymer composites
Abstract Polymer composites with salts or conductive fillers are promising for various solid‐state energy storage applications, where processability is often determined by their rheological properties. This study investigates the effect of lithium salts and conductive fillers on the rheological behavior of polylactic acid (PLA)‐based composites. We specifically examine how these additives influence complex viscosity and the interactions between the salt, fillers, and polymer. Our findings reveal that adding salt to the polymer reduces its viscosity, whereas adding conductive fillers imparts a shear‐thinning property, which is advantageous for thermal processing methods like thermal drawing, injection molding, or 3D printing. The combination of salt and conductive fillers results in multifunctional electrode‐electrolyte composites with enhanced shear‐thinning behavior and improved storage modulus. Characterizations through x‐ray diffraction, electrical measurements, and transmission electron microscopy link the electrical properties and morphology with rheological behavior. The formation of a robust filler network in these composites ensures stable viscoelastic behavior across a range of temperatures and frequencies, indicating their suitability for efficient manufacturing of polymer‐based solid‐state electrode‐electrolyte composites via thermal processing. HighlightsShear‐thinning behavior enhanced by conductive fillers.Viscosity increased with CB and CNT fillers, forming robust networks.Salt reduced viscosity but filler networks dominated flow behavior.Filler combinations led to stable viscoelastic properties across temperatures.Polymer electrolyte–electrode composites improved processability and storage modulus.
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- PAR ID:
- 10643779
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Polymer Composites
- Volume:
- 46
- Issue:
- 8
- ISSN:
- 0272-8397
- Format(s):
- Medium: X Size: p. 6998-7011
- Size(s):
- p. 6998-7011
- Sponsoring Org:
- National Science Foundation
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