Effect of Composition on the Molecular Dynamics of Biodegradable Isotactic Polypropylene/Thermoplastic Starch Blends
[ 1 ] Instytut Technologii Materiałów, Wydział Budowy Maszyn i Zarządzania, Politechnika Poznańska | [ P ] employee
2019
scientific article
english
- NMR spectroscopy
- dielectric relaxation
- polymer dynamics
- chain relaxation
- polymer blends
EN Polyolefins such as polypropylene are used in an immensely broad range of commodity products and account for the largest volume of synthetic polymers generated worldwide. For this reason, this family of thermoplastics contributes significantly to solid waste both on land and in the ocean. One viable approach to mitigate this growing problem and simultaneously reduce the cost of and dependence on petroleum-based polymers relies on blends wherein an added biopolymer can promote natural biodegradation. Due to their chemical dissimilarity, however, nonpolar polyolefins and polar biopolymers tend to phase-separate, in which case a fundamental, molecular-level understanding of the role of polymer/polymer interfaces on chain mobility in blends differing in composition is needed. In the present study, the molecular dynamics of blends composed of isotactic polypropylene (iPP) and glycerol-plasticized thermoplastic starch (TPS) are investigated by solid-state proton nuclear magnetic resonance and dielectric relaxation spectroscopies. Blends prepared by twin-screw extrusion range in composition from 10 to 70 wt % TPS, and their morphologies and thermal properties are examined by scanning electron microscopy and differential scanning calorimetry, respectively. This comparative analysis establishes the influence of TPS on the molecular dynamics of biphasic iPP/TPS blends relative to the constituent homopolymers.
10.09.2019
16050 - 16059
140
140
7,632