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The improvement of the compatibility between two nonpolar rubber blends has a pivotal role to obtain superior blend properties. In this work, we utilized a facile and biofriendly modification approach of natural bentonite (BT) clay by two renewable resins, namely antibacterial gum rosin (GR) and soybean long oil alkyd resin (LAR). Which are considered to be toxicity-free reinforcing substance, thus preserving the bio-character of the substance. They used to increase the interlayer spacing distance between the BT galleries. This was proven by XRD and FT-IR. Natural rubber (NR)/styrene-butadiene rubber (SBR) blend was loaded with variable proportions of EBT-based GR and LAR bio-resins ranging from 3 to 15 wt.%. The ultrasonic and tensile properties were used to assess the compatibility between the rubber blends. The outcomes revealed that NR/SBR-3EBT-GR and NR/SBR-15EBT-LAR nanocomposites possessed higher tensile strength and rapture at break. Furthermore, the proposed mechanism of EBT by GR and LAR bio-resins with NR/SBR blend was studied. The both nanocomposites were then subjected to different measurements such as morphology by SEM and TEM, H-pull-out adhesion between rubber blends and polyester (PET) cords, and antibacterial activity. These new filled blend systems can be effective supporting a wide range of potential applications such as green tubeless tires technologies. [ABSTRACT FROM AUTHOR]

Improving eco‐friendly coating‐based materials for wool artifacts, such as kilim fabric can inspire new‐fashion design avenues for conserving ancient cultural heritage. Thus, this research addresses an efficient treatment agent from natural rosin acids (R) and dapsone (D) with variable sublethal proportions of synthesized titanium dioxide nanoparticles (TiO2 NPs) (i.e., 0.1%, 0.3%, and 0.6%) for modifying kilim fabric (KF) using a dip‐coating method. The nanostructure of prepared TiO2 nanoparticles and their particle size were examined by x‐ray diffraction (XRD) and Zetasizer analyzer. The data showed that the majority of prepared TiO2 oriented to a rutile‐type structure with an average hydrodynamic diameter of 48.30–49.65 nm. The KF‐R/D‐0.3% TiO2 NPs specimen provided the best tensile properties reached ~3192 N compared with the untreated KF (i.e., 1125 N). This finding confirmed by SEM observations. Whereas, the specimen containing decorated TiO2 NPs (i.e., 0.6%) possessed higher flammability resistance property compared with other specimens. Moreover, XRD and FTIR results for treated KF specimens demonstrated the significant role of TiO2 NPs, which react with KF keratin either by new linkages or through chelating geometry to form a compact KF matrix. This contributed to enhance the tensile and flammability properties. Additionally, a great achievement in antibacterial properties occurred when TiO2 NPs used and their inhibitory zones were 18–36 mm, depending on the bacteria and specimen type. Highlights: Novel treatment of KF fabric‐based bioagents with sublethal contents of TiO2 NPs was successfully prepared by dip‐coating route.The tensile force and flammability of treated KF fabric were greatly enhanced.A great achievement in antibacterial activity was noticed when TiO2 added.These treated fabrics have excellent possibility for use in conserving cultural heritage. [ABSTRACT FROM AUTHOR]

Both biodegradable UV-blocking and antimicrobial films are extremely demanded, especially for food packaging to meet the increasing sustainable requirement for the human health and the environment. Thus, the objective of this research was to fabricate antibiofilms based biodegradable Poly(butylene adipate-co-terephthalate) / organoclay (PBAT/OC) bionanocomposites incorporating with different proportions of cumin essential oil (CEO) as a toxicity-free product without requiring ZnO, TiO2, Ag-NPs or other nanoparticles. The composition of CEO was characterized by GC-MS. PBAT/OC bionanocomposites with variable proportions of CEO were prepared by solvent casting approach. The synergistic effect of CEO on the morphology, UV-shielding, and antibacterial/antioxidant activities was studied. The results revealed that the dispersion of clay layers in the matrix was affected when the CEO content was increased. The incorporated natural CEO into PBAT/OC nanocomposite was enhanced the UV-shielding properties (i.e. 100% blocking for UV-B and nearly up 95% for UV-A), and antimicrobial/antioxidant activities, especially at high oil concentration. Whereas for mechanical properties, the findings showed inferior tensile and modulus values, because of plasticizing CEO effect. The data in this research provide very promising formulations for fabricating sustainable PBAT-based antimicrobial and UV-protecting films for perspective applications in light-sensitive packaging such as drugs, food products or in agriculture mulch films. [ABSTRACT FROM AUTHOR]

The demand for reactive dyes in industries has increased rapidly in recent years, and producing a large quantity of dye-containing effluent waste contaminates soils and water streams. Current efforts to remove these harmful dyes have focused on utilizing functionalized nanomaterials. A 3D polyurethane foam loaded with reduced graphene oxide (rGO) and ZnO nanocomposite (PUF/rGO/ZnO) has been proposed as an efficient structural design for dye degradation under the influence of visible light. The proposed structure was synthesized using a hydrothermal route followed by microwave irradiation. The resultant 3D PUF/rGO/ZnO was examined and characterized by various techniques such as XRD, FTIR, SEM, EDAX, BET, and UV–visible spectroscopy. SEM data illustrated that a good dispersion and embedment of the rGO/ZnO NPs within the PUF matrix occurred. The adsorption capacity for neat PUF showed that around 20% of the Methylene blue (MB) dye was only adsorbed on its surface. However, it was found that an exceptional adsorption capacity for MB degradation was observed when the rGO/ZnO NPs inserted into the PUF, which initially deteriorated to ~ 70 % of its initial concentration. Notably, the MB dye was completely degraded within 3 h. [ABSTRACT FROM AUTHOR]

In this research, sponge ethylene propylene diene rubber (EPDM) nanocomposites based on functionalized multi‐walled carbon nanotubes (f‐MWCNTs) and foaming agent azodicarbonamide (AZD) were successfully fabricated as potential acoustic‐absorbing foams. Two crosslinking systems were utilized for stabilizing the foam structure and improving its properties by subsequent sulfur and electron beam irradiation at 50 kGy as a fixed dose. The impacts of the concentration of AZD, f‐MWCNTs and crosslinking systems on acoustic and physico‐mechanical properties were investigated. The results manifested that the optimum foaming content was 3 phr. The acoustic data exhibited satisfactory enhancement in the sound absorption coefficient (α) for irradiated foam nanocomposites compared to unirradiated nanocomposites. This was attributed to the barrier effect of f‐MWCNTs in reducing the pore size of the foam, leading to an increase in the tortuous path in the foam matrix that stifled the sound waves from transferring into the bulk. Likewise, the compression properties were also improved. However, tensile stress and strain at break values for irradiated foams relatively decreased. The data obtained revealed an excellent possibility of using these EPDM foam nanocomposites for potential applications such as acoustic panels and airborne sound insulation. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Natural volatile antibacterial and anti-mycotoxin tea tree oil (TTO) with rice bran (RB) were used as a solid carrier for achieving a sustained release profile with high antimicrobial efficiency in polyethylene films. Acrylic acid (AAc) monomer was grafted onto a low-density polyethylene (LDPE) through melt blending using a Brabender Plasti-Corder. The low-density polyethylene-grafted acrylic acid (LDPE- g -AAc) was thoroughly characterized by attenuated total reflectance–Fourier transform infrared spectroscopy. LDPE and LDPE- g -AAc (80/20) were mixed with different contents of untreated RB and treated TTO/RB using melt blending to obtain sustainable composites, namely LDPE/LDPE- g -AAc/RB and LDPE/LDPE- g -AAc/TTO-RB, respectively. The effect of the addition of untreated and treated RB on the properties of biocomposites was assessed by using mechanical, barrier, and thermal properties. A prominent decrease in water vapor transmission rate occurred when adding 30 wt% of TTO/RB to LDPE/LDPE- g -AAc blend compared to virgin polymer. This decrease was due to the barrier effect of lignocellulosic material, particularly at high bio-filler content. The prepared biocomposites revealed good thermal stability when compared to virgin LDPE. Moreover, the biodegradability and antimicrobial properties of LDPE/LDPE- g -AAc/TTO-RB biofilms were enhanced with increasing TTO/RB contents from 10 phr to 30 phr due to the combination between LDPE- g -AAc and TTO. The obtained data revealed excellent possibility for using biopolymer grafted with antimicrobial TTO by adding RB for food packaging and biomedical purposes. [ABSTRACT FROM AUTHOR]

At present, renewable and biodegradable biocomposites materials have drawn much attention as promising green materials in different domains of application such as intelligent food packaging, biomedical and drug delivery, bio-membranes, automotive, as well as in industrial composting applications. The current review deals with the advances in preparation methods and technical applications of these biocomposites. Different biomass materials obtained from renewable resources such as coffee grounds (CG), nanocellulose and date stones are developed to be used as smart reinforcing agents in biodegradable biopolymers for improving their overall properties. Conversely, some drawbacks are associated with the use of lignocellulosic materials as reinforcing agents, especially their high humidity absorption, poor wettability, and incompatibility with most biopolymers. Thus, novel processing techniques and different aspects are proposed in this review to produce high performance lignocellulosic reinforced materials with better properties. Facial and green modification of organoclay (OC) by antibacterial natural rosin and stearic acid to obtain toxicity-free expanded OC is also discussed. Green modification using OC can also be used as compatibilizing and reinforcing material for different incompatible biopolymers such as chitosan, carboxy methyl cellulose (CMC) and polylactic acid (PLA). Ultimately, the future vision on the challenges and the environmental issues towards CO 2 emission which is associated to the risk assessment of these bionanomaterials are also discussed. • The present review deals with the advances in the preparation & technical applications biocomposites materials. • Renewable resources such as coffee grounds, nanocellulose & date stones using as smart reinforcing agent in biocomposites. • Green modification of organoclay by antibacterial natural rosin& stearic acid to obtain toxicity-free expanded organoclay. • Future vision on the challenges and the environmental issues towards CO 2 emission. [ABSTRACT FROM AUTHOR]

The need of using biodegradable fillers as polymer reinforcements instead of the polluting and hazard fillers has recently become a very important issue. Therefore, the aim of this study was the utilization of date stones (DS) as reinforcing and flame retardant biofiller in polyamide‐6 (PA6) with and without maleic anhydride‐grafted polypropylene (PP‐g‐MAH) compatibilizer. The composition of DS powder was revealed by X‐ray fluorescence (XRF) and chemical methods. Scanning electron microscopy images of biocomposites showed better compatibility of filler/polymer interface at 20 wt% DS and 5 wt% of the compatibilizer. Fourier transform infrared spectroscopy (FTIR) results confirmed our suggested reaction mechanism. The dynamic data showed satisfied enhancement in the storage modulus (E′) for maleated PA6 at 20 wt% DS filler. The tensile and impact strengths of the biocomposites enhanced for maleated PA6. The presence of the biofiller had no distinct effect on the thermal stability of the biocomposite. The flame retardant properties significantly improved with increasing DS filler content. The X‐ray diffraction and FTIR data revealed that the char layer acted as an insulating barrier to oxygen and heat transfer between the gas phase and the condensed phase thus reduced the heat release rate during the burning. POLYM. COMPOS., 39:1978–1987, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Three types of bio-alkyd resins varies in their oil content and viscosity were added to EPDM rubber mix loaded by three bonding system consisting of Hexamethylenetetramine, Resorcinol and Hydrated silica (HRH). The mixes were charged by certain amount of thermal carbon black. Rubber dough was spread on polyester sheet fabric. The peel strength was used to measure the adhesion strength. The rubber-proofed fabric subjected to UV irradiation at different period of times. The dielectric constant, volume resistivity, thermal stability, water and air permeability of the various rubber coated fabric were examined. The addition of the bio-alkyd resin improved the various mechanical and physical properties of the rubber coated fabric materials. The suggested mechanism of bio-alkyd resin between EPDM and polyester fabric was also studied. [ABSTRACT FROM PUBLISHER]