Abstract
Polyethylene terephthalate (PET) waste often contains a large amount of thermally unstable contaminants and additives that negatively impacts processing. A reduced processing temperature is desired. In this work, we report using a renewably sourced tall oil fatty acid (TOFA) as a modifier for recycled PET. To that end, PET was compounded with TOFA at different concentrations and extruded at 240 °C. Phase transition behaviors characterized by thermal and dynamic mechanical analyses exhibit shifts in the melting and recrystallization temperatures of PET to lower temperatures and depression of glass transition temperature from 91 to 65 °C. Addition of TOFA also creates crystal-phase imperfection that slows recrystallization, an important processing parameter. Changes in the morphology of plasticized PET reduces and stabilizes the melt viscosity at 240 and 250 °C. Melt-spun, undrawn continuous filaments of diameter 36-46 μm made from these low-melting PET exhibit 29-38 MPa tensile strength, 2.7-2.8 GPa tensile modulus, and 20-36% elongation. These results suggest a potential path for reusing waste PET as high-performance polymeric fibers.
| Original language | English |
|---|---|
| Pages (from-to) | 10709-10715 |
| Number of pages | 7 |
| Journal | ACS Omega |
| Volume | 3 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 30 2018 |
Funding
This project is supported by the Sun Grant Initiative and by Agriculture and Food Research Initiative Competitive grant no. 2014-38502-22598 from the USDA National Institute of Food and Agriculture and by the USDA National Institute of Food and Agriculture, Hatch project 1012359. N.A.N. acknowledges support from the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy, BioEnergy Technologies Office Program for the rheological analysis of the materials. A.K.N. acknowledges support from the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the US Department of Energy. The NMR portion of this research was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.
