Wooden Polymer Composites of Poly(vinyl chloride), Olive Pits Flour, and Precipitated Bio-Calcium Carbonate

As a filler to be inserted into poly(vinyl chloride) (PVC), low-cost olive pits flour (OPF) and precipitated bio-calcium carbonate (PBCC)-produced PVC/OPF/PBCC composites have been used with high stability and rigidity compared to PVC. Hydrogen bonding is generated between OH cellulose in OPF and H in PVC. Composite tensile modulus increased in PVC grid in the presence of PBCC and OPF, possibly because of a filler restriction effect on the polymer chains. The hardness also increased as both OPF and PBCC increased. The mechanical tendency of the PVC/OPF composite was improved by adding a low content of PBCC particles with the PVC network, resulting in a smart distribution in the range of 10% by weight, and it was reduced by adding more than that percentage. The successful distribution of PBCC in PVC/OPF composite strengthened the mechanical path. The morphology and possible interface adhesion of components in the composite were demonstrated by scanning electron microscopy (SEM). The PVC SEM images showed a homogeneous, smart, and consistent surface, while the PVC/60 wt % OPF SEM images showed a large number of voids that suggested weak PVC/OPF interactions. The SEM images showed outstanding PBCC distribution in the PVC/OPF matrix for the PVC/50 wt % OPF/10 wt % PBCC composite. Due to the accumulation of PBCC particles producing cavities, the distribution of particles became nonhomogeneous at percentages above 10 wt %. At a low filler material, better spread of PBCC particles in the PVC grid was achieved. Owing to the polarity of OPF, the H2O absorption and thickness swelling of PVC/OPF/PBCC composites showed higher amounts than PVC. PBCC improved the thermal stabilization and the neutralization of Cl- negative ions as an acid acceptor of secondary PVC stabilization.