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- Avella, Angelica, 1995, et al.
(författare)
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Reactive melt crosslinking of cellulose nanocrystals/poly(ε-caprolactone) for heat-shrinkable network
- 2022
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Ingår i: Composites Part A: Applied Science and Manufacturing. - : Elsevier BV. - 1359-835X. ; 163
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Tidskriftsartikel (refereegranskat)abstract
- Focusing on the challenge of non-biodegradable plastics replacement, we propose a design for peroxide-initiated crosslinking of biodegradable poly(ε-caprolactone) (PCL) and renewable cellulose nanocrystals (CNCs) bionanocomposites. An industrially scalable water-assisted reactive melt-processing (REx) is studied to explore the hypothesis of synergy between simultaneous effects of water on improving CNC dispersion and boosting PCL branching/crosslinking. We demonstrate that the melt processing control enables the preparation of targeted thermoplastic/thermoset bionanocomposites with gel content up to ≈ 40 %, identified as the limit of their melt-processability. Structural characterization reveals that ≈ 70 wt% of the initial CNC content is irreversibly incorporated in a percolating network, enhancing the crosslinked bionanocomposites properties. The bionanocomposites' complex viscosity and elastic character increase with the gel content, thus improving PCL melt performance. Furthermore, the irreversible entrapment of CNCs in the 3D percolating network provides heat-shrinkability, indicating a potential of the reacted bionanocomposites for heat-triggered shape-memory.
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| 2. |
- Venkatesh, Abhijit, 1989, et al.
(författare)
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Water-assisted melt processing of cellulose biocomposites with poly(ε-caprolactone) or poly(ethylene-acrylic acid) for the production of carton screw caps
- 2022
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Ingår i: Journal of Applied Polymer Science. - : Wiley. - 1097-4628 .- 0021-8995. ; 139:6
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Tidskriftsartikel (refereegranskat)abstract
- Composites in 25 kg batches were compounded of cellulose nanocrystals (CNC) and thermomechanical pulp (TMP) and shaped into caps at industrial facilities on a pilot-plant scale. Some of the material was also injection molded into plaques to compare the effect of laboratory-scale and pilot-scale compounding of poly(ethylene-co-acrylic acid) (EAA7) and poly(caprolactone) composites reinforced with 10 wt% CNC and TMP. The materials compounded under laboratory-scale conditions showed a different morphology, improved mechanical properties, and a higher viscosity, than the materials compounded on a pilot-scale. In some cases, the rheological properties of the melts indicated the presence of a relatively strong percolating cellulosic network, and the interphase region between the cellulose and the matrix appears to be important for the mechanical performance of the composites. After the compounding on a pilot scale, both the length and width of the pulp fibers was reduced. The TMP provided better reinforcement than the CNC possibly due to the higher aspect ratio.
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