Investigation of nanocomposite system with long-chain phosphorus-containing intercalator-modified montmorillonite nanosheets

The biodegradable polyester polybutylene adipate-co-terephthalate (PBAT) is a synthetic material that can melt and ignite easily when exposed to fire. Herein, we synthesized a long-chain phosphorus-containing intercalator by grafting 9,10-dihydro-9-oxa-10-phos-phaphenanthrene10-oxide (DOPO) onto long-chain quaternary ammonium salts (BHMDAC). Then inserted it into the sodium-based montmorillonite (MMT) nanosheets at the ratio of 25.9 wt% to obtain organic modified nanosheets. Subsequently, they were mixed into the PBAT matrix, and a series of performance such as microscopic dispersion, thermal stability, flame retardancy, mechanism and mechanical properties of nanocomposite were investigated. Compared with PBAT (1138.42 kW/m²), PBAT/MMT-(DOPO-BHMDAC) 5 wt% exhibited the lowest peak heat release rate value (508.04 kW/m²), which was reduced by 55.37 %. After adding 1 wt% MMT/DOPO-BHMDAC, the tensile strength of the sample increased from 25.1 MPa to 32.0 MPa, and the elongation at break increased to 826 %. This work provides a new perspective for future research on high-performance degradable polyester materials. © 2023 Published by Elsevier Ltd.