This research aimed to enhance the properties of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biocomposites by incorporating hemp microcrystalline cellulose (MCC). Additionally, to improve interfacial adhesion between PHBV and MCC phases, a compatibilizer consisting of epoxidized natural rubber (ENR) grafted with microfibrillated cellulose (MFC) modified by vinyltrimethoxysilane (ENR-vinyl silanized MFC) was introduced. The addition of 5 wt% MCC increases the flexural modulus by approximately 65%. The use of ENR-vinyl silanized MFC as a compatibilizer demonstrated improved compatibility, as observed in scanning electron microscope (SEM) images. After 30 days of accelerated weathering (QUV) exposure, the flexural strength of the PHBV-based biocomposite with ENR-vinyl silanized MFC and MCC (vinyl silanized MFC biocomposite) was superior to that of the other samples. The remaining flexural strength can be sequentially categorized as follows: vinyl silanized MFC > MFC > non-MFC > PHBV. The Tg of PHBV-based biocomposites showed no significant change. Interestingly, the crystallinity of the vinyl silanized MFC biocomposite was the highest among all materials and demonstrated higher hydrophobicity. This makes the vinyl silanized MFC biocomposite a suitable material for construction, furniture, and both exterior and interior decoration.

The widespread use of cellulose nanofiber (CNF)-based aerogels is hindered by their limited flame retardancy and mechanical properties. This study addresses these challenges by developing cellulose nanofiber/sodium alginate/fly ash (CNF/SA/FA) aerogel through a one-pot method, utilizing industrial waste fly ash (FA) as a reinforcing material. Various characterization and analytical techniques were employed to evaluate the properties of the CNF/SA/FA aerogel. The findings have revealed that resulting aerogel exhibited excellent thermal insulation performance, with a thermal conductivity of 0.485 W/(m·K), along with an impressive compressive strength of 88.4 kPa and favorable shape processability. Vertical combustion tests demonstrated a V-0 rating, indicating superior flame retardancy, and the aerogel achieved a remarkable 79.16% residual carbon, confirming their effective heat shielding capabilities. Notably, the incorporation of FA significantly enhanced both the thermal and mechanical properties of the composite aerogel, presenting a sustainable and effective solution to optimizing the properties of aerogel for thermal insulation.

Natural fibre-reinforced polymer composite (NFRPC) has been introduced as one of the solutions to overcome the ecological and environmental problems accompanying the widespread usage of polymeric materials in every facet of life. However, the organic nature of both natural fibres (NFs) and polymers increases their flammability behaviour, and this, in turn, limits their application. In this regard, this work concentrates on studying the effect of adding flame retardants (FR) to jute-reinforced epoxy composites (JRECs), either by treating the jute fabric with diammonium phosphate (DAP) or adding DAP powder to the epoxy resin matrix on the flame retardancy performance as well as the mechanical properties. The results showed that the effect of the incorporation method of DAP either to jute fabric or to resin matrix has a significant difference on the flammability test results at low concentrations; however, at higher concentrations, the flame retardancy performance is not affected by the technique of adding FR to the composite system. On the other hand, the mechanical properties are significantly affected by the method of incorporating FR to JRECs at all concentrations. Moreover, the results obtained from JRECs with FR systems were evaluated and compared with the literature by constructing selection charts that relate the flame retardancy level to mechanical properties.

Appropriate protection and guiding are crucial during peripheral nerves repair. New generation nerve guidance conduits (NGCs) should not only provide mechanical support for the damaged nerve but also support healing processes. One of the most promising tissue regeneration applications is fibrous biomaterials since they are characterized by high porosity, flexibility, and strength. Additionally, they enable cell adhesion and proliferation. In this study, novel fibrous nanocomposites were obtained by applying the electrospinning technique, using polylactic acid (PLA) as a polymeric matrix which was further modified with metallic nanoparticles coated with conductive polymers. Such an approach resulted in the obtainment of biomaterials with a potential ability to conduct nerve impulses. The chemical structure of the obtained composites, as well as the morphology of ready products and separate nanocomponents, were investigated using Fourier-transform infrared spectroscopy (FTIR), transmission electron microscope (TEM) and scanning electron microscope (SEM) techniques. Furthermore, conductive and swelling properties in various media were determined. Finally, biomaterials were confirmed to be non-cytotoxic to L929 mouse fibroblasts and 1321N1 human glial cells. Based on the presented results, it can be concluded that nanofibrous nerve guidance conduits have all the key properties in the process of peripheral nerve regeneration and may constitute an important step in novel NGCs development.

Sago starch (SS) was blended with natural rubber (NR) using nanoclays, namely montmorillonite (MMT), kaolinite (KAO), and kaolinite modified by dimethyl sulfoxide (KAO-D) to enhance its physical and mechanical properties. Each nanoclay was incorporated at 2, 4, 6, and 8 wt%, respectively. The SS80NR20 (80 wt% of sago starch and 20 wt% of natural rubber) biocomposites were characterized by solubility of water, water vapor transmission, mechanical and thermal properties. The constituent interaction and morphology of the SS80NR20 biocomposites were also presented by using X-ray diffraction (XRD) technique and scanning electron microscope (SEM). The findings demonstrated that the inclusion of clays significantly improved both the water resistance and tensile properties when compared to the SS80NR20 blend. In the SS80NR20 biocomposites, MMT at 6 wt% exhibited the lowest moisture content, solubility in water, and water vapor transmission. As the amount of nanoclay in the biocomposites increased, their tensile strength dramatically increased whilst their strain at break had a tendency to diminish. Strong interaction by establishing the intercalated structure of MMT, and KAO within SS80NR20 biocomposites were attributed to both physical and mechanical properties, while the weak interaction at the interface of SS and NR was attributed to KAO-D.