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A set of renewable and biodegradable hydrogels based on acid whey and cellulose derivatives blended with poly(lactic acid) (PLA) were designed as eco-friendly biopolymeric material for sustainable agricultural applications. The physico-chemical properties of the hydrogel were evaluated using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and rheological measurements. The effect of the whey/polysaccharide/PLA hydrogel on soil quality improvement (water retention study, biodegradability, loading capacity and release of the fertilizers) and the growth pattern of Raphanus sativus and Phaseolus vulgaris has been also studied. The addition of PLA has been found to improve mechanical properties of the hydrogel. The introduction of 20% wt PLA extended decomposition time of hydrogels by 25% which makes the material more stable in the environment and maintaining the soil humidity for longer. The increasing the amount of PLA led to a rise in hydrogel viscosity brought about better entrapment efficiency of the fertilizers (86–92% for KNO 3 and 87–96% for urea, resp.) compared to control (82% for KNO 3 and 85% for urea, resp.). The novel hydrogels with swelling ratio of up to 500% showed potential as a sustainable water reservoir for plants improving water retention capacity of the soil by 30%. • Renewable and biodegradable whey/cellulose derivatives-based hydrogels mixed with low-molecular weight PLA were prepared. • Effect of different PLA content on hydrogel properties was evaluated • The hydrogels demonstrate a high water holding capacity and excellent biodegradability. • Acting as a source of water a nutritive whey agents for plants and for slow release of fertilizers. • Promising alternative to commercial hydrogels based on synthetic polymers. [ABSTRACT FROM AUTHOR]

Exposure to endocrine-disrupting chemicals (EDCs) has been linked to harmful effects in biota due to their widespread chemical persistence. In this paper, we report on the fabrication of electrospun polylactic acid (PLA) based nanofibers functionalized with TiO 2 nanoparticles. The PLA-based TiO 2 nanofibers were further stabilized with the incorporation of halloysite (HNT) particles. The nanofibers were fabricated in varied concentrations of HNT (5, 10, 15%), while TiO 2 was kept at 10% for all the prepared samples. The fabricated samples were evaluated for elimination of synthetic 17α-ethinylestradiol (EE2) hormone as a model EDC pollutant. By using combined adsorptive and photocatalytic processes, the as-prepared samples were evaluated in a continuous flow system under dark and UV-light irradiation for EE2 removal. The best-performing sample with an optimized concentration of PLA/TiO 2 /HNT (85, 10, 5%) was able to eliminate 71.6% of EE2 hormone under UV irradiation at a hormone concentration of 0.1 mg/L. The maximum removal capacity obtained was 1.26 mg/g in 2 h, which best fitted the pseudo-first-order kinetics model. The sample was further utilized for additional experiments by changing experimental parameters, such as contact time, solution pH, and flow rate. To elucidate the actual degradation of the EE2 hormone, LCMS analysis was carried out to monitor the formation of by-products, which indicated that EE2 was fragmented into different potentially benign molecules. Finally, the best-performing sample was utilized for ten cyclic runs under optimized conditions for which the sample maintained sufficiently high degradation without any loss in structural integrity. Overall, the results showed that the developed PLA/TiO 2 /HNT nanofibers have a high potential to target persistent organic pollutants. [Display omitted] • PLA-based nanofibers were functionalized with TiO 2 and HNT nanoparticles. • The as-prepared nanofibers were evaluated using ethinylestradiol hormone. • Elimination of EE2 by tandem synergistic adsorptive and photocatalysis processes. • Reusability of the fibers was determined after ten cyclic operations. • LCMS analysis was carried out to identify the formation of degraded byproducts. [ABSTRACT FROM AUTHOR]

Nanocellulose (NC), a one-dimensional nanomaterial, is considered a sustainable material for water and wastewater purification because of its promising hydrophilic surface and mechanical characteristics. In this regard, nanostructured membranes comprising NC and two-dimensional (2D) nanomaterials emerged as advanced membranes for efficient and sustainable water purification. This article critically reviews the recent progress on NC-2D nanostructured membranes for water and wastewater treatment. The review highlights the main techniques employed to fabricate NC-2D nanostructured membranes. The physicochemical properties, including hydrophilicity, percent porosity, surface roughness, structure, and mechanical and thermal stability, are summarized. The key performance indicators such as permeability, rejection, long operation stability, antifouling, and interaction mechanisms are thoroughly discussed to evaluate the role of NC and 2D nanomaterials. Finally, summary points and future development work are highlighted to overcome the challenges for potential practical applications. This review contributes to the design and development of advanced membranes to solve growing water pollution concerns in a sustainable manner. [Display omitted] [ABSTRACT FROM AUTHOR]

This work describes the preparation of a novel biopolymer hydrogel based on acid whey, cellulose derivatives and polyvinyl alcohol (PVA). The hydrogel was prepared and characterized with the aim of producing an environmentally-friendly soil amendment to increase water retention capacity of the soil. The findings showed considerable swelling properties of the hydrogels depending on the PVA content and crosslinking density. The samples with PVA in a concentration 2.5 % and 5 % were more rigid, the gel fraction increased with a subsequently decrease in their swelling capacity. The hydrogels crosslinked with 15 % of citric acid demonstrated a constant swelling ratio (SR) of around 500 % within 10 swelling/drying cycles. The hydrogels crosslinked with 10 % citric acid and supplemented with 1 % of PVA showed SR of 1000–1400 % caused by less crosslinked polymer network and increased pore volume for water uptake. It was found that hydrogel with a higher gel fraction had a stable structure. Supplementing PVA at 5 % extended the period of decomposition of the hydrogel material by almost 60 % in the soil environment and soil humidity was maintained for longer. Applying 2 % of the hydrogel 5PVA to soil increased the water retention capacity by 19 %. • An environmentally-friendly soil conditioner was prepared for sustainable agricultural applications. • The effect of polyvinyl alcohol on the swelling properties and biodegradability of the hydrogels was evaluated. • Addition of 5 % PVA extended the period of biodegradation of the hydrogel in soil by almost 60 %. • The results show the potential of acid whey to be a source of nutritive whey agents for plants. [ABSTRACT FROM AUTHOR]

Composite materials based on PLA have been studied in depth for many applications, including food packaging. This manuscript describes extensive research conducted on a biodegradable polymer (PLA), inorganic filler (CaCO 3), and polyester-based plasticizer (PEP, based on a copolymer of low-molecular-weight PLA and PEG) prepared under semi-industrial conditions, as applicable for the packaging of hot food. The properties of the composite were achieved by post-processing annealing, notably its thermal stability, thereby permitting contact of the material with hot food. The manner of processing was deemed suitable for deployment at an industrial scale, moreover, the thermal stability of the final product endured, evidencing its applicability for such packaging. Change in the morphology of the structure of the composite material depended on the composition and annealing process, as detailed herein. The effect of the post-production thermal annealing on the molecular weight of samples was studied using the gel permeation chromatography. The thermal properties of the composites were investigated by differential scanning calorimetry, dynamic mechanical analysis, and thermogravimetric analysis. The crystallinity was assessed using X-ray diffraction technique, while mechanical behavior was tested in relation to the given tensile properties, shape stability at high temperature, and permeability by the transmission rates of gas/water vapor. [Display omitted] • PLA composite with CaCO 3 and plasticizer was prepared under semi-industrial conditions with a post-processing annealing. • The properties of the composite depended on the morphology and volume fractions of the crystalline and amorphous regions. • The two additive components and given technological conditions lends shape stability to the composite. • The composite was suitable for contact with hot food or use as packaging for foodstuffs that are heated in microwave ovens. [ABSTRACT FROM AUTHOR]