Thermal Behavior of the Porous Polymer Composites Based on LDPE and Natural Fillers Studied by Real Time Thermal Microscopy

Foaming of the biodegradable polymer composites and melting of the gas-filled materials were studied using thermal microscopy. Composite materials under investigation were based on the low density polyethylene and natural products used as the polymer composite fillers: wood flour and corn starch. Porous structure of the composite material was obtained using a chemical porogen “Hydrocerol BIF”. It has been shown that the foaming and melting processes occur differently in the polymer composite samples containing either different amount of the fillers or the same content of the filler with different particle size fractions. Thermal behavior of the composite samples was shown to be different from the behavior of pure polyethylene, which indicates non-additivity (superadditivity) of the contribution of the above components to the thermal behavior of the final composite material. All the results obtained using heating stage (hot stage) microscopy were in good agreement with the SEM and DSC data.