Development and characterization of renewable source composites to replace petrol-based polymers into interior door trims

Abstract

The Mechanical properties of PHA/PLA blends can be optimized trough the variation of the PHA contents on the blend. It's possible to predict the flexural and tensile properties recurring to Rule of Mixtures, Kerner-Uemura-Takayanagi, Nicolai-Narkis and Béla-Pukánsky models. All of them will validate the experimental obtain values and they anticipate a good adhesion between both phases. Nevertheless, for low levels of incorporation of PHA (up to 30%), where PLA is expectantly the matrix, the experimental data seems to deviate from the perfect adhesion models, suggesting a decrease on the adhesion between both polymeric phases. The impact energy varies over 157% over the entire blend composition. It's possible to identify that for blends with PHA weight fraction lower than 50% the impact strength of the blend is higher than the pure base polymers. The highest synergetic effect is found for the blend PHA/PLA of 30/70. The second maximum is found for the inverse composition. PLA has a Heat Deflection Temperature substantially lower than PHA. For the blends, the HDT increases with the increment upon the % of incorporation of PHA. Up to 50% PHA (PLA as matrix), the HDT is practically constant and equal to PLA value. Over this point (PHA matrix), the HDT of the polymer blends increases linearly with % of addition of PHA.