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Purpose This study aims to get rid of non-degradable polyvinyl chloride (PVC) waste as well as sunflower seed cake (SSC) waste by preparing eco-friendly composites from both in different proportions to reach good mechanical and insulating properties for antimicrobial and antistatic applications. Design/methodology/approach Eco-friendly composite films based on waste polyvinylchloride (WPVC) and SSC of concentrations (0, 10, 20, 30 and 40 Wt.%) were prepared using solution casting method. Further, the effect of sunflower seed oil (SSO) on the biophysical properties of the prepared composites is also investigated. Fourier transform infrared spectroscopy, X-ray diffraction (XRD), scanning electron microscope, mechanical, thermal, dielectric properties were assessed. Besides, the antimicrobial and biodegradation tests were also studied. Findings The crystallinity increases by rising SSC concentration as revealed by XRD results. Additionally, the permittivity (ε′) increases by increasing SSC filler and SSO as well. A remarkable increase in dc conductivity was attained after the addition of SSO. While raw WPVC has very low bacterial activity. The composite films are found to be very effective against staphylococcus epidermidis, staphylococcus aureus bacteria and against candida albicans as well. On the other hand, the weight loss of WPVC increases by adding of SSC and SSO, as disclosed by biodegradation studies. Originality/value The study aims to reach the optimum method for safe and beneficial disposal of PVC waste as well as SSC for antistatic and antimicrobial application.

Carbon black (CB), obtained by incomplete combustion of heavy petroleum products, is the most important filler used to improve the properties of various rubber composites. Its production process causes very serious environmental impacts in addition to its dependence on nonrenewable resources. Therefore, the trend has been to use eco‐friendly alternative materials that reduce the pollution associated with the CB production process and at the same time achieve the required mechanical properties of rubber composites. Biochar, a carbon‐rich solid product, could fulfill this role. It can be obtained by pyrolysis of organic matter such as agricultural waste in the absence of air at temperatures of 400–600°C. Herein, biochar was used in different ratios with CB to investigate its effect on the mechanical properties of styrene/butadiene rubber. The chemical composition of biochar and CB was investigated using a scanning electron microscopy and X‐ray fluorescence. In addition, the thermal properties, tensile strength, elongation at break, as well as thermo‐oxidative aging of the prepared rubber were studied. The tensile strength for styrene/butadiene rubber (SBR) composites containing 100% CB was 14.9 MPa, which decreases by adding biochar where it becomes 13.5, 11.2, 9.5, and 6.9 for SBR composites containing 25%, 50%, 75%, and 100% biochar, respectively. Furthermore, the vulcanized sample with 25% biochar (E2) shows higher retained tensile strength values than that containing 100% CB (E1) with increasing the aging time.

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Purpose The purpose of this study is to manufacture composites from sawdust and polymer high-density polyethylene (HDPE) with different loading from alum as natural and cheap flame retardant and subsequently characterized using standard analytical tools. Design/methodology/approach Artificial wood plastic composites (WPCs) were prepared by mixing HDPE with sawdust as a filler with constant ratio (2:1) using hot press. Polyethylene-graft-maleic anhydride (PE-g-MAH) used as a coupling agent between two parents of the composites with different ratios (2.5, 5, 7 and 10). Alum as a flame retardant was incorporated into HDPE with 5 phr polyethylene grafted with maleic anhydride (PE-g-MAH) with different ratios (10, 15 and 20). Flame retardant efficiency was investigated using differential scanning calorimetry, thermal gravimetric analysis and the technique of ASTM E162. Findings The results revealed that the composite containing 5 phr from (PE-g-MAH) exhibited higher mechanical properties and this proved that (PE-g-MAH) act as an efficient coupling agent using the aforementioned ratio. The results also revealed that incorporation of alum as a flame retardant increased the thermal stability of the composites. Originality/value Artificial WPCs are ecofriendly materials with a wide range of applications in the constructions field. Moreover, they have high mechanical and physical properties with low cost. Evaluate alum as a natural and cheap flame retardant.