Selected properties of biocomposites on the basis of PHBV with cellulose fillers

Abstract

The paper presents selected properties of the developed biocomposites based on PHBV poly (3-hydroxybutyric co-3-hydroxyvaleric acid) biopolymer. The PHBV biopolymer is obtained by the copolymerization of 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The biopolymer used for the tests contained 8% of poly(3-hydroxyvaleric acid). For the preparation of the composite, three types of fillers: wood flour, hemp fiber and flax fiber were used in search for the best possible mechanical properties of composite. During the selection of filler types, the availability and price in the geographical area of Poland as well as mechanical properties were taken into account. Fillers were alkalized and fiber modification parameters were determined. The following mass percentages of fillers in the tests: 15%, 30%, 45%, 50% and various fiber lengths were used. To produce the biocom-posites the single- and twin screw extruders made by Zamak Company were used. The initial processing parameters were determined using DSC thermogram analyses. The technological parameters depended on the type of filler and its percentage content. The best mechanical properties, compared to generally available polymers like PP, PE, PVC or PS were obtained for the composite with hemp fiber. The developed composite is completely biodegradable. Better mechanical properties of produced composite in relation to e.g. PE or PP allow using it for the production of parts that are used in various branches of the economy.