Water Absorption Rate Research Articles

Influence of Interface Modification on the Moisture Absorption and Thermal Resistance of Ramie Fiber/Degradable Epoxy Composites.

Natural fiber/degradable epoxy composites have received much attention for their advantages of low carbon emissions, low environmental pollution, and utilization of renewable resources. However, the poor interfacial bonding strength and inferior moisture resistance of natural fiber/degradable epoxy composites restrict their application areas. In order to improve the moisture and heat resistance of natural fiber/degradable epoxy resin-based composites, this study modified the surfaces of ramie fibers with hydroxylated carbon nanotubes, silane coupling agents, and sodium hydroxide, respectively. Three types of modified ramie fiber/degradable epoxy composites, namely F-CN-DEP, F-Si-DEP, and F-OH-DEP, were prepared using a winding forming process. The water absorption rate and short-beam shear strength of the materials were tested under different environments, and the fiber morphology and thermal-mechanical properties of the materials were investigated by scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA). The results show that F-CN-DEP exhibited the lowest moisture absorption rate; the highest shear strength, of 43.8 MPa; and a glass transition temperature (Tg) of 121.7 °C. The results demonstrate that carbon nanotubes on the fiber surface can improve the interfacial stability of ramie fiber/degradable epoxy composites in humid and hot environments. These results give guidelines for the development of natural fiber/degradable epoxy composites.

Study on the influence mechanism of hydrophobic materials-MPTMS and DMDMOS on the water resistance performance of asphalt mixtures

The interfacial adhesion between aggregate and asphalt is a critical factor affecting the water damage resistance performance of asphalt mixtures. To enhance the adhesion between aggregate and asphalt, Methyltrimethoxysilane (MPTMS) and Dimethyldimethoxysilane (DMDMOS) were co-opted to modify the aggregate surface. The interfacial strength between aggregate and asphalt was analyzed by water boiling test and contact angle experiment, and the mechanism of aggregate interfacial modification was investigated by combining SEM, FTIR and MD. The results showed that: hydrophobic treatment of aggregates reduces the water absorption rate of aggregates in a wet environment and significantly improves the water damage resistance of asphalt mixtures; MPTMS and DMDMOS reduced the aggregate surface polarity component, thus improving the match between aggregate and asphalt; The optimal processing environment for aggregates is acidity and 30 minutes. Further mechanistic tests and simulations showed that the reactive Si-O portion of the polymer reacts with the Si-O-C portion of MPTMS and DMDMOS to form hydrophobic clusters on the surface of the polymer, increasing the aggregate surface roughness. The clusters attract asphalt molecules to arrange closely and orderly around them. The intramolecular interactions and molecular angular energy of asphalt molecules are significantly reduced, which improves the stability of the aggregate-asphalt system, and further enhances the bonding energy between the aggregate and the asphalt, thus improving the water damage resistance of asphalt mixtures.

Preparation and Performance of Ceramic Tiles with Steel Slag and Waste Clay Bricks.

Steel slag and waste clay bricks are two prevalent solid waste materials generated during industrial production. The complex chemical compositions of these materials present challenges to their utilization in conventional alumina silicate ceramics manufacturing. A new type of ceramic tile, which utilizes steel slag and waste clay brick as raw materials, has been successfully developed in order to effectively utilize these solid wastes. The optimal composition of the ceramic material was determined through orthogonal experimentation, during which the effects of the sample molding pressure, the soaking time, and the sintering temperature on the ceramic properties were studied. The results show that the optimal ceramic tile formula was 45% steel slag, 35% waste clay bricks, and 25% talc. The optimal process parameters for this composition included a molding pressure of 25 MPa, a sintering temperature of 1190 °C, and a soaking time of 60 min. The prepared ceramic tile samples had compositions in which solid waste accounted for more than 76% of the total material. Additionally, they possessed a modulus of rupture of more than 73.2 MPa and a corresponding water absorption rate of less than 0.05%.

Biocomposite Based on Polylactic Acid and Rice Straw for Food Packaging Products.

Plastic containers, commonly produced from non-biodegradable petroleum-based plastics such as polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET), raise significant environmental concerns due to their persistence. The disposal of agricultural waste, specifically rice straw (RS), through burning, further compounds these environmental issues. In response, this study explores the integration of polylactic acid (PLA), a biodegradable material, with RS using a twin-screw extruder and injection process, resulting in the creation of a biodegradable packaging material. The inclusion of RS led to a decrease in the melt flow rate, thermal stability, and tensile strength, while concurrently enhancing the hydrophilic properties of the composite polymers. Additionally, the incorporation of maleic anhydride (MA) contributed to a reduction in the water absorption rate. The optimized formulation underwent migration testing and met the standards for food packaging products. Furthermore, no MA migration was detected from the composite. This approach not only provides a practical solution for the disposal of RS, but also serves as an environmentally-friendly alternative to conventional synthetic plastic waste.

Impact of rice variety, cooking equipment and pretreatment method on the quality of lightly milled rice

Lightly milled rice is a healthier choice compared to refined white rice. In this study, the effects of variety, cooking equipment and pretreatment method on the quality of six varieties of lightly milled rice from China after cooking was investigated through physics, chemistry and instrumental analysis method. Nanjing-No.5055 has the best eating quality, Xiadao-No.1 has higher appearance score, and Fengliangyouxiang-No.1 has the lowest glycemic index. Compared with microwave oven and electric cooker, steamer has a more significant positive impact on component retention, eating quality and sensory quality, but the former has lower cooking time and higher glycemic index. Soaking can effectively improve the water absorption rate, thus reducing hardness. Cleaning affects component retention but is beneficial for sensory quality. The most obvious variation in organizational structure can be observed in the steamer and soaking processes. These findings could serve as a valuable reference for the processing of lightly milled rice.

Influence of Solid Waste Material Content on the Properties of Steel Slag-Waste Clay Brick Ceramic Bricks

Steel slag and waste clay brick are two common solid wastes in industrial production, and their complex chemical compositions pose challenges to the production of traditional alumina silicate ceramics. To investigate the influence of steel slag and waste clay brick on the performance of CaO–SiO2–MgO ceramic materials, this study examined their effects on the mechanical properties, crystal composition, and microstructure of the ceramics through single-factor experiments. The results demonstrate that when keeping the dosage of waste clay brick and talcum powder constant, a 43% dosage of steel slag yields optimal performance for the ceramic materials with a modulus of rupture of 73.01 MPa and a water absorption rate as low as 0.037%. Similarly, when maintaining a constant dosage of steel slag and talcum powder, a 41% dosage of waste clay brick leads to superior performance of the ceramic materials, with a modulus of rupture reaching 82.17 MPa and a water absorption rate only at 0.071%. Furthermore, when keeping the dosage of steel slag and waste clay brick constant, employing a talcum powder dosage of 24% results in excellent performance for the ceramic materials with a modulus of rupture measuring 73.01 MPa while maintaining an extremely low water absorption rate at only 0.037%. It is noteworthy that steel slag contributes to akermanite phase formation while talcum powder and waste clay brick contribute to diopside phase formation.

Experimental Study on the Effect of Date Palm Powder on the Thermal and Physico-Mechanical Properties of Gypsum Mortars

Date palm leaves have been diachronically applied in building materials in the Middle East and North Africa (MENA) region, so as to enhance specific properties, such as volume stability and strength. This research work concerns an experimental study on the impact of date palm leaflet powder (DPLP) on the thermal and physico-mechanical properties of gypsum mortars. A series of mortar compositions were prepared with different proportions of DPLP (0, 1, 3, and 5% w/w of binder) and variant particle size (0.5, 1, and 1.5 mm). The results showed that the mortars containing DPLP exhibited significant changes in their properties due to variations in DPLP concentration and particle size. Increased DPLP led to lower density, higher porosity, and water absorption rate, whereas mechanical strength and thermal conductivity were decreased according to the DPLP proportion and size. This research provides valuable insights into the use of sustainable and renewable building materials, highlighting the benefits of exploiting agricultural waste in the constructional sector. The findings lay the groundwork for future research and innovation in environmentally friendly construction technologies.

Accelerated carbonation of recycled concrete aggregate in semi-wet environments: A promising technique for CO2 utilization

The practical implementation of accelerated carbonation for recycled waste concrete is impeded by sluggish carbonation efficiency. In contrast to previous carbonation enhancement schemes using high-pressure gas and/or complex pre-/post-processing, this study introduces a novel semi-wet carbonation method that achieves high-efficiency carbonation of recycled concrete aggregates (RCA) in a practically simple way. A noteworthy carbonation degree of 10.6 % was achieved within 30 min at room temperature and ambient pressure, which enhanced the RCA by reducing the water absorption rate and porosity by 3.6 % and 20 % respectively. The formed CaCO3 is primarily in calcite form with poorer crystallinity and smaller grain size and the formed silica gel features a lower polymerization degree compared with those formed in wet carbonation. It is due to that the carbonation reactions for the semi-wet scenario happen at the spatially confined water film of the solid-liquid interface. Moreover, the addition of sodium bicarbonate significantly accelerated the semi-wet carbonation, which is due to the weak alkaline environment lowering the CO2 speciation free energy as revealed by reactive molecular dynamics simulations. The proposed semi-wet carbonation method provides a promising way of pushing industrial CO2 capture and utilization.

Impact of pre-soaked lime water carbonized recycled fine aggregate on mechanical properties and pore structure of 3D printed mortar

Compared to natural fine aggregate, recycled fine aggregate has disadvantages such as high water absorption and poor strength. Accelerated carbonization is considered a method to enhance recycled aggregate performance. However, the lack of substances available for carbonation reaction in old cement mortar restricts the enhancement of RFA performance. In this study, a pre-soaked lime-water carbonization method was employed to enhance carbonization efficiency and improve cement mortar performance by introducing additional sources of calcium. Therefore, the focus was on investigating the effects of pre-soaked lime-water carbonization-treated recycled fine aggregate with different replacement ratios (0%, 30%, 50%, 70%, 100%) on the mechanical properties of 3D printed mortar. In addition, combining XRD、SEM-EDS, and X-CT microscale testing methods, the study analyzed the influence of carbonized recycled fine aggregate on the pore structure of 3D printed recycled mortar. The purpose was to reveal the reinforcement mechanism of pre-soaked lime water composite carbonization. Experimental results showed that the pre-soaked lime water carbonization method improved the physical properties of recycled fine aggregate, with the most significant decrease in the water absorption ratio, which decreased by 53.89%. Incorporating appropriate carbonized recycled fine aggregate can enhance the mechanical properties of 3D printed mortar, increase interlayer bonding strength, reduce mechanical anisotropy and overall porosity, and improve pore defects. Defects on the aggregate surface are filled with CaCO3 carbonization products, improving the pore structure and strengthening the interfacial transition zone, thus enhancing the resistance of 3D printed recycled mortar to external forces. The findings of the present work not only improve the utilization of recycled sand but also provide methods and ideas for improving the properties of 3D printed recycled mortar.

Study on Reducing Water Absorption of Recycled Aggregates (RAs) by Microbial Mineralization.

Crushing waste concrete and using it directly as RAs has the disadvantages of high porosity and high water absorption. To achieve the reuse of resources, the researchers use microbial mineralization methods to further reinforce RAs. In this paper, the effect of the microbial carbonic anhydrase mineralization method on the water absorption of RAs was investigated, and the macroscopic analysis was performed by determining the indexes of water absorption and apparent density of RAs before and after the modification, and the microscopic analysis of RAs by using the methods of SEM, XRD, DSC, and EDS as well. According to the microscopic analysis, the mineralization products of microorganisms are calcium carbonate crystals, and with the increase in microbial liquid concentration, the water absorption rate of RAs shows a trend of decreasing and then increasing, and it can be found through the microscopic morphology that abundant mineralization products attached to the surface of the aggregate lead to the surface of the aggregate becoming rougher and more porous. The method of soaking the RAs in 3% bacterial solution and 0.1 mol/L calcium acetate solution followed by carbonation with 20% CO2 resulted in a 4.85% reduction in water absorption.

Study on physicochemical and anti-corrosion performance of methylsiloxane-based hydrophobic powder modified mortar

The porous hydrophilic nature of cement-based material is susceptible to water and corrosive media, severely reducing the durability. In this paper, methyl siloxane-based hydrophobic powder was prepared, and its effect on the physicochemical and anti-corrosion properties of mortar with different water-cement ratios were investigated. The results show that the addition of hydrophobic powder significantly improved the hydrophobic properties of mortars. Especially for the mortars with w/c ratios of 0.2 and 0.4, it showed superhydrophobicity with a water contact angle up to 156.5 ° and 152.3 ° respectively. Lower w/c ratio mortar has a denser microstructure, which reduces the water absorption rate of the mortar, and the hydrophobic powder enhances the hydrophobic effect of low w/c ratio mortar more significantly. The methyl siloxane groups in the hydrophobic powders will bind to the C-S-H gel in the mortar through Si-O bonding, preventing the C-S-H gel connections from forming a continuous network structure. This increased the pore volume and reduced the compressive strength by 14.6%-22.7%, but the total hydration degree was increased, and significant corrosion protection of the steel rebar was demonstrated.

Analysis of Soil Permeability Batu Bulan Dam’s Right Secondary Irrigation Canal in Sumbawa, Indonesia

The assessment of soil and water conditions is crucial in planning and management of an irrigation system. This study focused primarily on investigating the fine aggregate flow absorption conditions of the soil from the secondary irrigation canal of the Batu Bulan Dam’s right bank in Sumbawa Regency, Indonesia. Soil permeability level was determined in a laboratory setting using standard water absorption parameters of an irrigation canal. Analysis of specific gravity and absorption of fine aggregate showed that sand sample (A) had a bulk specific gravity of 2.53, a saturated surface dried specific gravity of 2.55, and a water absorption of 0.92 percent. Sand sample (B) had a specific gravity of 2.53, a saturated surface dried specific gravity of 2.56 and an absorption rate of 1.02%. According to the characteristics of fine aggregate (sand) standard, the specific gravity range is between 1.6 and 3.3. Thus, the mud content value of the sand samples follows the standards set by SNI. The sand sample (A) exhibited a water absorption rate of 0.92%, whereas sand sample (B) displayed a water absorption rate of 1.02%. As per the Fine Aggregate Inspection Standard, the upper limit for water absorption in fine aggregate is prescribed as 3% of dry weight for concrete with abrasion and 5% of dry weight for non-abrasive concrete. Thus, the mud content value of the sand samples complies with SNI standards. The results suggest that future irrigation strategies should consider the distinct characteristics of native aquifers, the routes of groundwater movement, and the conveyance of soil nutrients to ensure the sustainability of agricultural development in secondary irrigation areas adjacent to reservoirs.

Usability of Trabzon stone as a natural building stone and aggregate

This study investigated the suitability of Trabzon stone, which is used as a building stone in many areas in and around Trabzon province, as an aggregate. It was found that the uniaxial compressive strength values of the samples taken from the quarry were 87-130 MPa, P-wave velocities were 5048-5642 m/s, density value was 2.58 g/cm3, apparent porosity values were 2.77-4.54%, water absorption values by weight were 1.04-1.78% and water absorption value by mass was 2.0%. Weight loss in the freeze-thaw test was 0.36%, weight loss in the wet-dry test was 0.22%, loss in the magnesium sulfate test was 13%, Los Angeles fragmentation resistance in coarse aggregate was 22%, abrasion resistance value was 18% and methylene blue value was 0.9%. When the results were analyzed, it was found that the mass water absorption rate and the magnesium sulfate test results were above the values required by the standards. Although these rocks are used as marble, it has been determined that the waste material is not suitable for use as ballast, crushed stone, stone fill, pere, and masonry for road and concrete construction. Despite this result, it is necessary to investigate the usability of materials from other marble quarries in the region as aggregates.

Enhancing Residential Construction Efficiency: Evaluating Interlock Blocks as a Sustainable Alternative to Traditional Brick Construction (A Case Study of Private Housing in Setipakha Height, Lalitpur)

In Nepal, traditional clay red bricks have been extensively used in residential and commercial construction, but their labour-intensive nature has prompted the exploration of alternative construction materials. This study investigates the feasibility of using interlocking blocks as a replacement for traditional bricks in residential housing, focusing on cost, strength, and socioeconomic acceptance. Through a combination of literature review, lab tests, and on-site observations, the properties of interlock blocks were evaluated and compared with traditional bricks. The study area, Setipakha Height in Lalitpur, provided a suitable context for data collection, given the prevalent use of interlock blocks in ongoing housing projects. Results from compressive strength tests revealed that interlock blocks exhibited comparable strength to both first- and second-class bricks, indicating their suitability for load-bearing applications. Additionally, interlock blocks demonstrated lower water absorption rates compared to clay bricks, suggesting enhanced durability and resistance to moisture-related issues. Furthermore, interlock blocks showed higher density and consistency, potentially offering greater structural integrity and material efficiency. Cost analysis indicated that interlock block masonry was more cost-effective than traditional brick masonry, with potential savings in construction time and labour requirements. Moreover, interlock blocks, when properly manufactured, could provide a sustainable alternative to traditional bricks, reducing environmental impact. In conclusion, interlock blocks present a promising alternative to traditional clay bricks in residential construction, offering advantages in terms of strength, durability, cost-effectiveness, and sustainability. Recommendations include the adoption of interlock blocks in construction projects, further research on their long-term performance, regulatory considerations, and increased awareness among stakeholders in the construction industry. Embracing interlock blocks has the potential to revolutionize residential construction practices in Nepal, contributing to sustainable development and meeting the housing needs of communities.

Effect of Intermittent Low-Pressure Radiofrequency Helium Cold Plasma Treatments on Rice Gelatinization, Fatty Acid, and Hygroscopicity.

To establish the safe and reproducible effects of cold plasma (CP) technology on food products, this study evaluated the gelatinization parameters, fatty acid profile, and hygroscopic properties of rice grains repeatedly treated with low-pressure radiofrequency (RF) helium CP (13.56 MHz, 140 Pa, 120 W-20s, 0-4 times, and 300 g sample). Compared with the untreated (zero times) sample, with an increase in CP treatment times from one to four on rice, the water contact angle and cooking time decreased, while the water absorption rate and freshness index increased, and the pH value remained unchanged. CP repeating treatments essentially had no effect on the gelatinization enthalpy, but significantly increased the peak temperature of gelatinization. From the pasting profile of rice that has been repeatedly CP treated, the peak, breakdown, and setback viscosities in flour paste decreased. CP repeating treatments on rice did not change the short-range molecular order of starch. Compared with the untreated sample, the first helium CP treatment maintained the content of C18:1n9c, C18:2n6c, and C18:3n3, but the second to fourth CP treatment significantly decreased contents of these fatty acids (FAs) as the C18:0 content increased. The first three CP treatments can increase the water and sucrose solvent retention capacity in rice flours. CP repeatedly treated rice first exhibits the similar monolayer water content and solid surface area of water sorption. Principal component analysis shows that contact angle, pasting parameters, and fatty acid profile in milled rice are quite sensitive to CP treatment. Results support that the effect of low-pressure RF 120W helium CP treatment 20 s on rice grains is perdurable, and the improvement of CP intermittent treatments on rice cooking and pasting properties is an added benefit, and the hygroscopic properties of rice was kept.

Improvement of the anti-corrosion coating properties of waterborne epoxy resin with the incorporation of fluoropolymer-modified silica nanofillers

The objective of this research was to enhance the corrosion resistance and mechanical properties of silica nanoparticles modified by a fluoropolymer (polyhexafluorobutyl acrylate, PHFBA) by incorporating them into a waterborne epoxy resin (WEP) coating system. Initially, polyhexafluorobutyl acrylate (PHFBA)-modified silica nanoparticles were synthesized using a two-step method, involving the grafting of 3-(isobutylloxy) propyl trimethoxysilane (KH570) onto SiO2 to produce SiO2@KH570, followed by a random copolymerization of SiO2@KH570 with hexafluorobutyl acrylate (HFBA) to obtain the fluoropolymer-modified SiO2 (FxSiO2). Subsequently, the chemical structure and elemental composition of SiO2, as well as the prepared SiO2@KH570 and FxSiO2 nanoparticles, were comprehensively investigated. Moreover, FxSiO2/WEP composite coatings with different amounts of fluoropolymer-modified nanofillers and x-F5SiO2/WEP composite coatings with varying amounts of F5SiO2 nanofillers were prepared and characterized. The findings revealed that the functionalized FxSiO2 exhibits superior dispersion, interface, and size effects, significantly enhancing the overall performance of WEP coatings. Notably, when 0.1 wt% F5SiO2 nanofiller was incorporated, the resulting 0.1-F5SiO2/WEP composite coating demonstrated a considerable impedance modulus (1.171 × 108 Ω∙cm2), relatively low water absorption rate (about 11 % after 20 d of immersion in water), and robust mechanical properties: a tensile strength of 6.07 MPa and an elongation at break of 37.36 %. Moreover, the hardness and adhesion of the composite coating remain unaltered. Furthermore, after 20 days of salt spray testing, the electrochemical impedance still reached 8.765 × 106 Ω∙cm2, indicating a favorable long-term anti-corrosion capability. Consequently, the integration of fluoropolymer-modified nanoparticles in water-based epoxy resins holds great potential.

TRILOCK BRICK : INOVASI DESAIN BATAKO BENTUK SEGITIGA DENGAN SISTEM INTERLOCK

As the construction industry in Indonesia continues to grow, it has significantly impacted the demand for building materials, particularly in the construction sector. One such material is "batako," which is used as a wall filler, along with cement as a bonding material (grout). Therefore, there is a need for a solution that provides easier workability during installation and is cost-effective. The objective of this research is to innovate and analyze the design of triangular-shaped batako with an interlocking system on each side. The methodology used involves experimental testing in a laboratory and follows the Indonesian National Standard (SNI) 03-0349-1989. The process includes material testing, specimen production, compressive strength testing, absorption testing, and a cost comparison analysis. The research resulted in the development of "trilock brick," a triangular-shaped batako measuring 36 cm in length and 9 cm in thickness. The average compressive strength at 28 days was 9,487 MPa, with an average water absorption rate of 5.344%. The installation cost per 1 m2 was Rp. 76,802, with a grout thickness of 0,5 cm. This research demonstrates that this innovation possesses compressive strength and water absorption values comparable to conventional batako. Additionally, trilock brick offers economic advantages with a cost difference of up to 13% compared to conventional batako requirements.

PH‐Responsive itaconic acid‐based villous‐like hydrogels for water‐plugging materials

AbstractThe development of new methods to improve the water absorption performance of polymeric materials, taking into account their environmental friendliness, is a promising research direction in Itaconic acid based water‐absorbent polymeric materials. In this study, from the perspective of environmental protection, we propose to design highly absorbent hydrogels with a novel villous‐like structure by using hydrophilic itaconic acid as the raw material and combining it with a novel villous‐like network structure to substantially increase the contact area between the hydrogel and water, thus improving the water absorption rate of the hydrogel. Itaconic acid is water‐soluble and renewable. The widespread use of polymeric water‐absorbent polymers from traditional petroleum sources poses a serious threat to the sustainability of ecosystems, and therefore, itaconic acid has attracted much attention as an alternative to petroleum‐based polymers. The villous‐like network structure is inspired by the villi of the small intestine, the special presence of which expands the absorptive surface area of the small intestine by a factor of about 600, and it is therefore hypothesized that the introduction of this special structure could help the hydrogel to greatly increase the contact area with water and thus achieve the high water absorption properties of the hydrogel. This is also the first time that the villus‐like network structure has been applied to Itaconic acid based hydrogels. The results show that the hydrogel has the property of rapid water absorption and swelling and the water absorption rate of the hydrogel can reach up to 2210 g/g, and the villous‐like structure formed by the hydrogel can be observed in the SEM image. The water‐absorption test of the hydrogel showed that when the molar mass ratio of itaconic acid to acrylic acid was 1:4, the hydrogel absorbed water and swelled rapidly in a short time. The results of the water retention test showed that the hydrogel still existed after 5 days, and the water retention was greater than 86%. In addition, the hydrogel had high reusability, and the water absorption performance of the hydrogel could still reach 89.12% after 6 cycles of the water absorption test. Hydrogel with high water‐absorbing property has good application prospects as fast swelling material in the field of flood control of water conservancy projects.

Enhancing solar-driven atmospheric water harvesting by a bilayer macroporous hydrogel

The adsorption-based atmospheric water harvesting technique has shown great potential in providing clean water. An ideal device for atmospheric water harvesting should enable the massive and quick release of water after it is rapidly absorbed by the moisture adsorbent. At present, however, the moisture adsorbent still experiences issues such as a slow water absorption rate, hampered adsorption–desorption kinetics, and a low total water yield. In this paper, a bilayer moisture adsorbent (BMA), which glues a hydrophilic macroporous layer for rapid water adsorption and a carbonized sunlight-absorbing layer for both water harvesting and desorption acceleration, is introduced. Further evidence suggests that it is the stable, fluffy, and rough porous structure of the BMA that helps to harvest atmospheric water efficiently. The fully carbonized BMA exhibits a water absorption capacity of up to 396% at a relative humidity of 90%, which is 20% higher than a monolayer sample. More importantly, the desorption efficiency of the half-carbonized BMA reaches 98% under 1 sun illumination. These results jointly demonstrate that the BMA can play the dual role of absorbing moisture and light, allowing for rapid atmospheric water harvesting, massive water storage, and efficient desorption under the light.

Characterization of Polylactic Acid Biocomposites Filled with Native Starch Granules from Dioscorea remotiflora Tubers.

Biocomposites were fabricated utilizing polylactic acid (PLA) combined with native starch sourced from mountain's yam (Dioscorea remotiflora Knuth), an underexplored tuber variety. Different starch compositions (7.5, 15.0, 22.5, and 30.0 wt.%) were blended with PLA in a batch mixer at 160 °C to produce PLA/starch biocomposites. The biocomposites were characterized by analyzing their morphology, particle size distribution, thermal, X-ray diffraction (XDR), mechanical, and dynamic mechanical (DMA) properties, water absorption behavior, and color. The results showed that the amylose content of Dioscorea remotiflora starch was 48.43 ± 1.4%, which corresponds to a high-amylose starch (>30% of amylose). Particle size analysis showed large z-average particle diameters (Dz0) of the starch granules (30.59 ± 3.44 μm). Scanning electron microscopy (SEM) images showed oval-shaped granules evenly distributed throughout the structure of the biocomposite, without observable agglomeration or damage to its structure. XDR and DMA analyses revealed an increase in the crystallinity of the biocomposites as the proportion of the starch increased. The tensile modulus (E) underwent a reduction, whereas the flexural modulus (Eflex) increased with the amount of starch incorporated. The biocomposites with the highest Eflex were those with a starch content of 22.5 wt.%, which increased by 8.7% compared to the neat PLA. The water absorption of the biocomposites demonstrated a higher uptake capacity as the starch content increased. The rate of water absorption in the biocomposites followed the principles of Fick's Law. The novelty of this work lies in its offering an alternative for the use of high-amylose mountain's yam starch to produce low-cost bioplastics for different applications.