Effects of nanoparticles on thermal degradation of polylactide/aluminium diethylphosphinate composites

• Pyrolysis of aluminium diethylphosphinate generated dimeric compounds.
• Presence of aluminium diethylphosphinate decreased thermal stability of PLA.
• The decrease was mainly due to the interactions of diethylphosphinic acid.
• Addition of SiO2, HNT and OMMT affected thermal degradation characteristics.
• Incorporation of montmorillonite improved thermal characteristics of PLA/AlPi.

We investigated the thermal degradation characteristics of polylactide (PLA) aluminium diethylphosphinate (AlPi) composites involving SiO2, halloysite (HNT) and organically modified montmorillonite (OMMT) via direct pyrolysis mass spectrometry. Presence of nanoparticles, SiO2, HNT and OMMT affected both thermal stability and relative yields of thermal degradation products of PLA/AlPi. The trans-esterification reactions and interactions between PLA and AlPi were depressed in the presence of SiO2 and HNT. The increase in thermal stability detected in the presence of OMMT was associated with generation of cross-linked structure as a consequence of reactions between the organic modifier of montmorillonite, the carbonyl groups of PLA and phosphinates.