학술논문

Direct 3D Printing of Recycled PET/PP Granules by Shear Screw Extrusion.
Document Type
Article
Source
Polymers (20734360). Dec2023, Vol. 15 Issue 24, p4620. 13p.
Subject
*THREE-dimensional printing
*FUSED deposition modeling
*SCREWS
*RECYCLED products
*MOLECULAR orientation
*POLYETHYLENE terephthalate
*PLASTIC extrusion
Language
ISSN
2073-4360
Abstract
This article introduces a one-step extrusion-based fused deposition modeling (FDM) approach for the challenging separation of polypropylene (PP) and polyethylene terephthalate (PET) during recycling. A shear screw printer (SSP) with shear elements was designed, and it was compared to a conventional single-screw printer (CSP) to investigate the differences in print stability, degradation levels, tensile performance, molecular orientation, and crystallization when preparing recycled PP and recycled PET blends. Although the retention effect of the SSP screw slightly increases the degradation of the blended rPP/rPET, the strong shear (2.6 × 104 s−1) applied near the extrusion exit improves the blending efficiency. The SSP also enhances molecular orientation, modulus of the parts, and reduces performance fluctuations. Additionally, the SSP has the potential to simplify the recycling process, enabling the transformation of blended recycled materials into products with just one melt process. [ABSTRACT FROM AUTHOR]