Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic Fragmentation
Viscosimetric experiments and microscopy measurements on microdispersions of polycaprolactone (PCL) plastics showed an unexpected exponential decrease in viscosity over the first 3 months and a plateau for a further 4 months of observations. This behavior is due to the release of nanoplastics from s...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-05-01
|
| Series: | Molecules |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1420-3049/30/10/2235 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850256631829364736 |
|---|---|
| author | Vincenzo Villani Pier Luigi Gentili |
| author_facet | Vincenzo Villani Pier Luigi Gentili |
| author_sort | Vincenzo Villani |
| collection | DOAJ |
| description | Viscosimetric experiments and microscopy measurements on microdispersions of polycaprolactone (PCL) plastics showed an unexpected exponential decrease in viscosity over the first 3 months and a plateau for a further 4 months of observations. This behavior is due to the release of nanoplastics from semicrystalline particles that reduce the viscosity of the dispersion, and leave stable and fine crystalline microplastics ranging in size from 30 to 180 μm. The development of nonlinear kinetic models for the fragmentation process from macro- to meso-, micro-, and nanoplastics reveals complex behavior that we call a cracking–leaching mechanism. The autocatalytic mechanical cracking of macroplastics larger than 5 mm is followed by a logistic-type mechanical cracking of mesoplastics between 5 and 1 mm. Therefore, microplastics smaller than 1 mm experience the leaching diffusion modeled via nonlinear coupled kinetic differential equations: semicrystalline microplastics quickly release nanoplastics from the amorphous fraction, followed by fine and stable crystalline microplastics. This proposed mechanism explains the size distribution of floating plastic debris in the oceans, with an unexpected gap of microplastics. Considering the outcome, a general reflection is made on the critical issues that currently appear unsolvable regarding plastic pollution. |
| format | Article |
| id | doaj-art-afc06f2425dd4f70967b0d5e0e2aa190 |
| institution | OA Journals |
| issn | 1420-3049 |
| language | English |
| publishDate | 2025-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj-art-afc06f2425dd4f70967b0d5e0e2aa1902025-08-20T01:56:35ZengMDPI AGMolecules1420-30492025-05-013010223510.3390/molecules30102235Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic FragmentationVincenzo Villani0Pier Luigi Gentili1Department of Basic and Applied Sciences, University of Basilicata, Campus Macchia Romana, 85100 Potenza, ItalyDepartment of Chemistry, Biology, and Biotechnology, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, ItalyViscosimetric experiments and microscopy measurements on microdispersions of polycaprolactone (PCL) plastics showed an unexpected exponential decrease in viscosity over the first 3 months and a plateau for a further 4 months of observations. This behavior is due to the release of nanoplastics from semicrystalline particles that reduce the viscosity of the dispersion, and leave stable and fine crystalline microplastics ranging in size from 30 to 180 μm. The development of nonlinear kinetic models for the fragmentation process from macro- to meso-, micro-, and nanoplastics reveals complex behavior that we call a cracking–leaching mechanism. The autocatalytic mechanical cracking of macroplastics larger than 5 mm is followed by a logistic-type mechanical cracking of mesoplastics between 5 and 1 mm. Therefore, microplastics smaller than 1 mm experience the leaching diffusion modeled via nonlinear coupled kinetic differential equations: semicrystalline microplastics quickly release nanoplastics from the amorphous fraction, followed by fine and stable crystalline microplastics. This proposed mechanism explains the size distribution of floating plastic debris in the oceans, with an unexpected gap of microplastics. Considering the outcome, a general reflection is made on the critical issues that currently appear unsolvable regarding plastic pollution.https://www.mdpi.com/1420-3049/30/10/2235plastic pollutionkinetic models of fragmentationpolycaprolactone (PCL)viscosity of dispersionsmicroplasticsnanoplastics |
| spellingShingle | Vincenzo Villani Pier Luigi Gentili Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic Fragmentation Molecules plastic pollution kinetic models of fragmentation polycaprolactone (PCL) viscosity of dispersions microplastics nanoplastics |
| title | Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic Fragmentation |
| title_full | Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic Fragmentation |
| title_fullStr | Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic Fragmentation |
| title_full_unstemmed | Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic Fragmentation |
| title_short | Viscosity of Polycaprolactone Microplastic Dispersions and Nonlinear Kinetic Models of Plastic Fragmentation |
| title_sort | viscosity of polycaprolactone microplastic dispersions and nonlinear kinetic models of plastic fragmentation |
| topic | plastic pollution kinetic models of fragmentation polycaprolactone (PCL) viscosity of dispersions microplastics nanoplastics |
| url | https://www.mdpi.com/1420-3049/30/10/2235 |
| work_keys_str_mv | AT vincenzovillani viscosityofpolycaprolactonemicroplasticdispersionsandnonlinearkineticmodelsofplasticfragmentation AT pierluigigentili viscosityofpolycaprolactonemicroplasticdispersionsandnonlinearkineticmodelsofplasticfragmentation |