The influence of oil content within lignocellulosic filler on thermal degradation kinetics and flammability of polylactide composites modified with linseed cake

Abstract Linseed cake (LC), a by‐product of oil extraction from linseed, due to high content of natural oil can be applied as a filler and modifying agent for polymeric composites. However, the presence of the flammable oil may change thermal properties of the resulting materials. The aim of this study is evaluation of the influence of oil content on flammability and thermal degradation of polylactide composites. The samples filled with 10 wt% of LC containing from 0.9% to 39.8% of oil were subjected to cone calorimetry, horizontal burning test and thermogravimetric analysis. Activation energy values of the thermal decomposition of the composites were calculated using Ozawa and Kissinger methods. The different LC grades and the crude oil were tested as well. Even though all the composite grades presented higher flammability and lower thermal stability than the neat resin, their burning behavior and the process of thermal decomposition did not depend on the oil content. Therefore, the oil‐rich grades of LC can be applied as an effective filler for polylactide without an increase in fire risk.