Burial Test Research Articles

Effectiveness and Risk Assessment Septic Tank Treatment Systems in Rural Cold Regions of China

Rural toilet reform in cold areas is the focus and difficulty of China’s toilet revolution. In this paper, by carrying out the septic tank gradient burial depth test and regular seasonal monitoring of the operation effect of rural septic tanks in cold areas, the frost protection effect and treatment effect of rural toilets in cold areas are clarified, which provide important references for the rural toilet revolution and its practical significance in cold areas of China. Based on controlled tests and correlation analysis methods, different gradient burial depths of septic tanks (40, 60, and 80 cm) and different seasonal operation effects (spring, summer, autumn, and winter) were studied to analyze the influence of factors such as burial depths and temperatures on the effectiveness of anti-freezing and treatment of septic tanks. The results found that the septic tank effluent indexes of the six cold-zone test households could not meet requirements of Class Ⅰ-B in the discharge standard of pollutants for municipal wastewater treatment plants (GB 18918-2002). (The criteria for Class I-B are as follows: COD emission limit of 60 mg/L; SS emission limit of 20 mg/L; TN emission limit of 20 mg/L; TP emission limit of 1 mg/L; NH3-N emission limit of 8 mg/L); The average removal of suspended solids (SSs), chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), NH3-N, and NO3-N by septic tanks was 79.7%, 21.8%, 10.5%, 13.5%, 9.76%, and 2.38%, respectively; the water temperature was significantly positively correlated with SS, TN, and TP; the double-layer insulated septic tank with medium burial depth (60 cm) could operate normally in cold areas in winter. The treatment effect of septic tanks on various indicators basically shows that summer > autumn > spring > winter. Temperature is the main limiting factor affecting the treatment effect of septic tanks. Capsule: By carrying out septic tank gradient burial depth tests and regular seasonal monitoring of the operating effect of rural septic tanks in cold areas, we can clarify the anti-freezing effect of rural toilets in cold areas and the effectiveness of treatment.

Amine-functionalized soy protein/graphene oxide aerogel for efficient removal of multiple sugar-derived contaminants (SDCs): Full life cycle exploration and interaction simulation

Sugar-derived contaminants (SDCs) pose significant environmental hazards and safety concerns, emerging as urgent issue. Using amine-modified soy protein (SPI) and graphene oxide (GO), an environment-friendly aerogel (PSPI/PGO) was synthesized to efficiently remove multiple SDCs. The equilibrium adsorption capacities of PSPI/PGO for melanoidins, caramels, and saccharin were 1124.2, 291.1, and 399.3 mg/g, respectively, surpassing those of previously proposed materials. A series of characterizations and experiments demonstrated that the porous PSPI/PGO exhibited high hydrophilicity, nontoxicity, excellent thermal stability, and sustainable capture properties. Emerging dynamic models (i.e., AOAS, EXT-INT, and LF-PC-AS) and multiple quantum chemical theory calculations (ESPL, ALIE, FMO, IGMH, and HSA) further revealed the capture of each SDC onto PSPI/PGO was driven predominantly by charge interactions, followed by H-bonding and intermolecular interactions. PSPI/PGO acts as an H-bonding acceptor in a diverse range of uptake processes for each SDC. The applicability of PSPI/PGO for treating real wastewater has been validated. The full lifecycle exploration of PSPI/PGO (including soil burial degradation tests, wastewater treatment, and garlic hydroponic experiments using depleted PSPI/PGO) underscores its considerable biocompatibility and potential for industrial applications.

Eco-Friendliness and Cost-Effectiveness of Reusable Sanitary Pads for Rural Women: A Model for Menstrual Hygiene Management in Low Resource Settings

Background Menstrual Hygiene Management (MHM) is fundamental to women’s health, well-being, and gender equality. The study aimed to assess the cost-effectiveness and acceptability of reusable sanitary pads among rural women in Pakistan, proposing a scalable model for improving MHM practices in low-income countries. Methods A cross-sectional study was conducted using Multi- Stage Cluster sampling to accomplish a sample size of 340 childbearing-age women from the rural areas of Sindh, Pakistan. The data was collected using a standard questionnaire regarding the affordability and accessibility of reusable versus disposable sanitary pads; further information was also gathered from Market surveys for MHM products. The biodegradability of the pads was assessed using a soil burial test. The data was analyzed using SPSS version 27. Results Our research found a significant preference for reusable sanitary pads. The biodegradability tests demonstrated that reusable pads had a superior degradation rate (1.88%) to disposable pads (1.59%) over four months. Economic assessments showed a low utilization of commercial pads (12.5%) due to affordability issues, with 87.5% using reusable cloths. Despite 70% awareness of menstrual hygiene, 48% of women showed interest in creating sanitary solutions, underscoring the feasibility of implementing locally sourced, cost-effective products across similar socio-economic landscapes. Conclusion The present study underscores the universal applicability of affordable, sustainable MHM solutions in rural communities of low-income countries, advocating for broader implementation of such models to address global menstrual hygiene challenges. Bangladesh Journal of Medical Science Vol. 23 No. 04 October’24 Page : 1030-1037

Investigation of Snake Grass/Casuarina/Cork Filler Reinforced Bio Polymer Hybrid Composite

The environment is continuously affected for various reasons, prompting researchers to seek solutions from different angles. This study explores the potential of mixing polymers with and without agricultural/bio fillers such as Snake Grass / Casuarina / Cork in various volume proportions, analyzing their mechanical properties. The hybrid materials are made with the polymers and bio fillers without any change in the quality of existing polymer products, the quality of hybrid materials is assured by the results of impact, flexural, and tensile tests. Finally, the biodegradability tests revealed weight loss in a soil burial test when bio-filler was added to the polymer composite.

Cure, mechanical and swelling characteristics of composites of neoprene rubber and starch from non-edible variety of dioscorea tuber

Composites of Polychloroprene rubber (CR, Neoprene rubber) reinforced with starch from non-edible variety of dioscorea tuber were prepared using three different vulcanizing systems. The cure, mechanical, solvent resistance and biodegradable characteristics of the composites were studied. The addition of starch from dioscorea tuber was found to improve CR’s tensile strength. The maximum torque value increases with the loading of filler and it was found to be the highest at 20 phr. The addition of starch from dioscorea tuber was found to improve CR’s tensile strength and highest value observed at 20 phr. Among the different curing systems studied, the modified DCP system shows maximum mechanical properties, optimum properties of the composites are at 20 phr. The values of the swelling coefficients were determined by examining the intake of the solvents N, N-dimethylformamide, acetonitrile, dimethyl sulfoxide and water by the composites. The soil burial test indicated that biodegradability of CR enhanced with the addition of starch. The findings of mechanical properties are supported by studies using scanning electron microscopy. Since starch is a naturally occurring biopolymer, adding it encourages microbial activity, which breaks down the composite components. This quality is essential for resolving plastic waste-related environmental issues. It is anticipated that the findings of this study will aid in the development of materials for specific product applications like gasoline hoses, tire sidewalls, seals, and so on.

Valorization of whey through green synthesis of silver nanoparticles for developing biodegradable plastic films with bactericide properties

This study explores the synthesis of silver nanoparticles (AgNPs) using untreated whey as a green approach, followed by their integration into biodegradable gelatin films for potential applications in antimicrobial packaging. UV–visible spectroscopy and scanning electron microscopy confirm the successful synthesis of AgNPs, which are seamlessly incorporated into flexible and semi-transparent gelatin films. Comparing films with and without AgNPs, subtle changes are observed in UV–visible and Fourier-transform infrared spectra that are attributed to the low AgNP concentrations. However, the resulting films with AgNPs exhibit effective bactericidal efficacy against E. coli. Moreover, soil burial tests demonstrate significant biodegradability, with up to 80% mass loss within two weeks, showing comparable rates between films with and without AgNPs. These results show the prospects of whey-derived AgNPs in the development of sustainable, antimicrobial biodegradable films with potential applications in various industries.

Preparation and Characterization of Biodegradable Plastic from Red Seaweed (Gracilaria sp.) from Coastal Areas in Bangladesh

AbstractBioplastics are biobased or biodegradable plastic synthesized from natural resources with similar features to conventional plastic and environmental sustainability. Seaweed species abundant in the coastal regions of Bangladesh are yet to be explored for developing biodegradable plastic to solve the plastic pollution problem. Semi‐refined kappa carrageenan was extracted from Gracilaria sp. with Pressurized Hot Water Extraction (PHWE) and blended with sorbitol and polyethylene glycol 1540 in this study, respectively. The presence of carrageenan and other functional groups was confirmed with FTIR analysis. The bioplastic films showed over 90 % biodegradability after 16 days of soil burial test and 98 % water solubility after immersion for 16 days. Maximum 20 MPa tensile strength and 44 % elongation were observed from the bioplastic films. The polyethylene glycol 1540 blended films showed better physical and mechanical properties. SEM analysis was conducted to evaluate the influence of tensile strength and elongation on the surface integrity of the bioplastic films. The findings indicate that Gracilaria sp. found in the coastal regions of Bangladesh, can be a potential candidate for developing bioplastics for food packaging and many other applications.

Extraction of Fungal Chitosan by Leveraging Pineapple Peel Substrate for Sustainable Biopolymer Production.

The cost-effective production of commercially important biopolymers, such as chitosan, has gained momentum in recent decades owing to its versatile material properties. The seasonal variability in the availability of crustacean waste and fish waste, routinely used for chitosan extraction, has triggered a focus on fungal chitosan as a sustainable alternative. This study demonstrates a cost-effective strategy for cultivating an endophytic fungus isolated from Pichavaram mangrove soil in a pineapple peel-based medium for harvesting fungal biomass. Chitosan was extracted using alkali and acid treatment methods from various combinations of media. The highest chitosan yield (139 ± 0.25 mg/L) was obtained from the pineapple peel waste-derived medium supplemented with peptone. The extracted polymer was characterized by FTIR, XRD, DSC, and TGA analysis. The antioxidant activity of the fungal chitosan was evaluated using DPPH assay and showed an IC50 value of 0.22 mg/L. Subsequently, a transparent chitosan film was fabricated using the extracted fungal chitosan, and its biodegradability was assessed using a soil burial test for 50 days. Biodegradation tests revealed that, after 50 days, a degradation rate of 28.92 ± 0.75% (w/w) was recorded. Thus, this study emphasizes a cost-effective strategy for the production of biopolymers with significant antioxidant activity, which may have promising applications in food packaging if additional investigations are carried out in the future.

Effect of beeswax and coconut oil as natural coating agents on morphological, degradation behaviour, and water barrier properties of mycelium-based composite in modified controlled environment

Non-degradable coatings made of petroleum-based plastics hinder the degradation performance of products. This highlights the urgent need to develop biodegradable, bio-based coatings derived from renewable resources to create a more sustainable and greener world with a smaller environmental footprint. This study endeavours to examine the effects of beeswax and coconut oil additions on the morphological, degradation, and water-barrier properties of mycelium-based composite (MBC). Coconut oil is supplemented with varying amounts of beeswax, comprising 0, 20, 40, 60, 80, and 100 wt%. Dip coating is applied to prepare coated-MBC at 65 °C for 2 min. The coated-MBC is characterized by water absorption test, water loss measurement, density measurement, yeast and mould test, shrinkage measurement, weight loss measu rement, soil burial test, Scanning Electron Microscopy (SEM) and macroscopic appearance. Findings revealed that a higher composition of beeswax (80 BW) leads to lower water absorption ability (26.25 %) and no fungal growth for 36 days, in contrast to uncoated-MBC (0 BW), which are used as a reference sample.

Effects of biodegradation of starch-nanocellulose films incorporated with black tea extract on soil quality

This study aimed to investigate the biodegradation behaviour of starch/nanocellulose/black tea extract (SNBTE) films in a 30-day soil burial test. The SNBTE films were prepared by mixing commercial starch, nanocellulose (2, 4, and 6%), and an aqueous solution of black tea extract by a simple mixing and casting process. The chemical and morphological properties of the SNBTE films before and after biodegradation were characterized using the following analytical techniques such as field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and fourier transform infrared (FTIR). The changes in soil composition, namely pH, electrical conductivity (EC), moisture content, water holding capacity (WHC), soil respiration, total nitrogen, weight mean diameter (MDW), and geometric mean diameter (GMD), as a result of the biodegradation process, were also estimated. The results showed that the films exhibited considerable biodegradability (35–67%) within 30 days while increasing soil nutrients. The addition of black tea extract reduced the biodegradation rate due to its polyphenol content, which likely resulted in a reduction in microbial activity. The addition of nanocellulose (2–6% weight of starch) increased the tensile strength, but decreased the elongation at break of the films. These results suggest that starch nanocellulose and SNBTE films are not only biodegradable under soil conditions but also positively contribute to soil health, highlighting their potential as an environmentally friendly alternative to traditional plastic films in the packaging industry.

High toughness and fast home-compost biodegradable packaging films derived from polylactic acid/thermoplastic starch/para-rubber ternary blends

This research aims to formulate biobased and biodegradable packaging films with high toughness and fast home-compost biodegradation using ternary blends of polylactic acid (PLA), Para rubber (NR), and thermoplastic starch (TPS) through blown-film extrusion. The TPS content in this work ranges from 5 to 20 wt%, while the PLA: NR ratio is fixed at 70:30. At this PLA: NR ratio, the blend with 10 wt% TPS (PNT10) exhibited the highest % elongation at break and tensile toughness. Peroxide radical initiator was investigated as a potential additive for improving the properties of the ternary blend. Our binary interaction study indicated that peroxide initiated grafting reactions of PLA–NR and NR–TPS pairs, while no grafting occurred between PLA and TPS. In ternary blends, the highest peroxide content (0.5 wt%) increased the % elongation at break up to 120%, with the tensile toughness reaching 7255 MJ/m3. The improved compatibility induced by peroxide addition was supported by enhanced dispersion of TPS in the PLA/NR matrices. Results from the room-temperature soil burial test indicated that the presence of TPS could significantly accelerate the home-compost degradation of PNT films compared to films produced from neat PLA and PLA/NR. This suggests its potential as both a cost reducer and a biodegradation accelerator.

The impact of ecological aging on the mechanical performance of jute-banana fibre phenol-formaldehyde hybrid composites

Natural fiber composites provide an environmentally favorable and sustainable alternative to traditional materials, greatly reducing environmental impact. Aging tests are required to evaluate the long-term mechanical performance and durability of these composites under varied situations, ensuring their dependability and safety over time. This study investigates the effects of ecological aging on jute-banana fiber reinforced phenol-formaldehyde (JBP-F) composites. The experiment involved fabricating JBP-F composites using jute and banana fibers with varying weight ratios (60:40, 50:50, 40:60, 30:70) and subjecting them to various aging tests like long-time water resistance, accelerated water resistance, thermal aging, hydrothermal aging, soil burial test, and accelerated weathering test. The result showed that the composite with a 50:50 jute-banana fiber to resin ratio (JBP-F50) outperformed the other compositions examined in terms of aging resistance. This balanced ratio likely optimized fiber-matrix interaction, leading to superior strength and water resistance. Higher fiber content composites (like JBP-F60) absorbed more water due to weaker bonding, while lower fiber content (JBP-F30) suffered more in high temperatures. All composites experienced strength loss during thermal and hydrothermal aging due to heat and moisture cycles. JBP-F50 again showed the least degradation, possibly due to the resin’s ability to recover. In soil burial tests, biodegradation impacted strength, with higher fiber content composites (JBP-F60) degrading more. Finally, weathering tests revealed some surface deterioration due to UV radiation. However, the resin offered protection, with JBP-F30 (higher resin content) experiencing the most weight loss.JBP-F50, with its balanced fiber-resin ratio, demonstrated the best resistance to various environmental stresses, making it a promising option for sustainable composite applications.

Combination Of Makahiya (Mimosa Pudica) Plant and Garlic(Allium Sativum) Peels as Alternative Raw Materials in Organic Kitchen Towel Production

Although kitchen towels are a household necessity, they have also become a contributing factor to deforestation because they are often composed of wood pulp, making it the reason for habitat loss. This study was conducted to test the capabilities of the Makahiya plant and Garlic peels as substitute raw materials for kitchen towel production. The process entails creating three kitchen towel samples with varying concentrations and putting them through three tests. This study also utilized the quasi-experimental method to test the hypothesis and the relationship of the variables. While conducting soil burial testing in one of the researchers’ residences, the researchers used laboratory testing with the Department of Science and Technology (DOST) for absorbency and durability testing. The findings illustrate that cellulose from the Makahiya plant and cellulose from Garlic peels work well together as an alternative raw material for kitchen towel-making. Researchers concluded that a 30:70 ratio— 30% cellulose from Makahiya and 70% cellulose from Garlic peels—was ideal for this production. The result presents a 1.13g average for soil burial, a 7-second average for absorbency, and 1.3 and 1.9 apparent elongation for durability. It just suggests that it could function as a replacement for those sold commercially.

Hydrothermal aging and soil biodegradation characteristics of biopolymer based sustainable composites

The current research endeavor examines the water absorption (in-service life) and soil biodegradation (end-of-the-service life) behavior of short sisal fiber (SF) reinforced poly (lactic acid) (PLA) and bio-based poly (butylene succinate) (bio PBS) composites. Samples were fabricated by extrusion-injection molding with varying sisal fiber loading of 10, 20, and 30 wt%. The water absorption test was conducted in distilled water at three distinct temperatures (5, 25, and 45 °C) for 336 h. The sorption behavior of composites was studied experimentally, and detailed diffusion kinetic behavior is discussed using Fickian diffusion models. The impact of fiber content and hydrothermal temperature on water diffusion and maximum water absorption was investigated in detail. A soil burial test was conducted in local farmland soil for 60 days to determine the influence of fiber content on the biodegradation characteristics of composites. After exposure to hydrothermal aging, it was concluded that fiber loading was most significant in affecting the maximum percentage of water absorption, whereas hydrothermal temperature was more relevant for higher water diffusion. Soil burial tests showed that SF/bioPBS composites degraded quickly as compared to PLA composites. Overall, composites made with bio PBS have shown an expected response than PLA composites in terms of water absorption and soil biodegradation.

Characterization of Composite Film Containing Polyvinyl Alcohol Cross‐Linked With Dialdehyde Cellulose Using Citric Acid as a Catalyst for Sustainable Packaging

ABSTRACTThis study is aimed at fabricating composite films by cross‐linking polyvinyl alcohol (PVA) and dialdehyde cellulose (DAC) in varying ratios using citric acid as a catalyst. The acetal formation between the two components was studied using FTIR. Characterizations of the physiochemical properties revealed that increasing the DAC ratio of the composite film improved the hydrophobicity, tensile strength and barrier properties (water vapour, UV and oxygen) of the films while reducing elongation at break (flexibility), swelling and solubility of the film in water. When the DAC ratio was elevated to 50%, the tensile strength was enhanced to 98 MPa. In comparison, flexibility diminished to 29%, the solubility of the film reduced to 10% and water vapour permeability was lower by two orders of magnitude than that of the control PVA film. The peroxide value of linoleic acid decreased from 21.2% ± 7.6 (packed with PVA film) to 9.9% ± 0.9 (packed with 50% DAC composite film) after 15 days. Furthermore, the composite films demonstrated effective absorption of UV radiation, with the order of effectiveness being UV‐C > UV‐B > UV‐A radiation. No significant difference in biodegradability was detected in the composite films with an increase in DAC ratio during indoor soil burial tests for 30 days. This study implies that the composite film could serve as an alternative sustainable packaging option, especially when transparency and high oxygen barrier properties are desired.

Changes of wood surfaces treated with natural-based products – Structural and properties investigation

Preservative systems based on vegetable seed oils and natural waxes from renewable sources may confer protection to wood under exposure to various environmental conditions. These, as non-toxic substances, can form an environmentally friendly and efficient protective layer on the wood surfaces, with beneficial effects on their water resistance and dimensional stability. Thus, these natural coatings may hinder biodegradation of wood products to a certain degree. In present paper, softwood samples (from Abies alba fir tree species), prepared as dried discs (25 to 30 mm diameter, 8 to 10 mm thickness), were surface impregnated by dipping using vegetable oils, namely Asclepias syriaca seed oil, and soybean oil, respectively. Beeswax treatment was also applied for comparison purposes. Surface chemistry and morphology, biodegradation process under controlled and simulated natural conditions, and water sorption behavior of wood samples were investigated. Fourier Transform Infrared spectroscopy, X-ray diffraction, and scanning electron microscopy methods were used for investigation of surface changes in wood samples before and after impregnation with natural based products, as well as under biodegradation conditions in soil burial tests.

Development of biocompatible packaging material: starch/PVA-based bio-composite enhanced with hydroxypropyl methylcellulose

ABSTRACT Hydroxypropyl methylcellulose (HPMC) incorporated bio-composite films (unplasticized and plasticized) were prepared from pregelatinized maize starch/polyvinyl alcohol (PMS/PVA) blends by solution casting method. 10% boric acid (BA) was used as crosslinker. The physico-mechanical properties (tensile strength (TS), elongation at break (%EB), water solubility and moisture uptake) of the bio-composite films were studied. The thermo-chemical stability of the biofilms was studied by FT-IR, TGA and DSC analysis. TS, %EB, water solubility and moisture absorbency of 10% HPMC containing unplasticized films were found 38.1 MPa, 8.5%, 61% and 32.3%, respectively, however, the films were hard and brittle. On the contrary, TS, %EB, water solubility and moisture absorbency of 10% HPMC plasticized films were found 19.2 MPa, 28.5%, 62.2% and 57.3%. The biofilms exhibited relatively low water solubility and moisture uptake compared to higher HPMC containing composite. The thermo-chemical analysis revealed that the HPMC incorporated plasticized film was more thermally stable compared to pure PMS, PVA, HPMC and other bio composite films due to strong hydrogen bonding interaction with BA. The biodegradability of HPMC incorporated plasticized films was confirmed by soil burial test (anaerobic condition, RH 98%, 3 months). Therefore, the plasticized biofilm would be considered an alternative approach for biocompatible packaging material.

High-performance biodegradable poly(vinyl alcohol)/starch composites via alkaline-regulated crystalline engineering

The increasing demand for environmentally-friendly products has led to a growing focus on the development of high-performance biodegradable materials. However, achieving a balance between mechanical strength, water resistance, and biodegradability remains a challenge. Herein, the successful preparation of exceptional biodegradable poly(vinyl alcohol) (PVA)/starch (ST) composites using alkaline-regulated crystalline engineering is reported. The findings demonstrate that the alkali promotes ST gelatinization while inhibiting its recrystallization, resulting in improved compatibility and good dispersion in the PVA matrix. In contrast, the alkali enhances the crystallization of PVA, thereby improving the composites' water resistance. The composites exhibit outstanding mechanical properties, with a strain at break of approximately 400 % and a toughness of 54 MJ/m3, surpassing most reported works. Even in high humidity and water environments, the composites maintain their mechanical strength, with a strength of 13 MPa after soaking in water for 1 d, significantly higher than films without the addition of alkali. Moreover, the composites exhibit excellent biodegradability, with a degradation rate exceeding 40 % after a 60-d natural soil burial test. The flame retardancy is also greatly enhanced, with a limiting oxygen index (LOI) of 30 %. This study offers a promising avenue for the development of high-performance biodegradable materials such as dip-coating fabric, fire retardant coating, and industrial packaging.

Eco-Friendly Textile-Based Wearable Humidity Sensor with Multinode Wireless Connectivity for Healthcare Applications.

Textile-based wearable humidity sensors are of great interest for human healthcare monitoring as they can provide critical human-physiology information. The demand for wearable and sustainable sensing technology has significantly promoted the development of eco-friendly sensing solutions for potential real-world applications. Herein, a biodegradable cotton (textile)-based wearable humidity sensor has been developed using fabsil-treated cotton fabric coated with a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) sensing layer. The structural, chemical composition, hygroscopicity, and morphological properties are examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), contact angle measurement, and scanning electron microscopy (SEM) analysis. The developed sensor exhibited a nearly linear response (Adj. R-square value observed as 0.95035) over a broad relative humidity (RH) range from 25 to 91.5%RH displaying high sensitivity (26.1%/%RH). The sensor shows excellent reproducibility (on replica sensors with a margin of error ±1.98%) and appreciable stability/aging with time (>4.5 months), high flexibility (studied at bending angles 30°, 70°, 120°, and 150°), substantial response/recovery durations (suitable for multiple applications), and highly repeatable (multicyclic analysis) sensing performance. The prospective relevance of the developed humidity sensor toward healthcare applications is demonstrated via breathing rate monitoring (via a sensor attached to a face mask), distinguishing different breathing patterns (normal, deep, and fast), skin moisture monitoring, and neonatal care (diaper wetting). The multinode wireless connectivity is demonstrated using a Raspberry Pi Pico-based system for demonstrating the potential applicability of the developed sensor as a real-time humidity monitoring system for the healthcare sector. Further, the biodegradability analysis of the used textile is evaluated using the soil burial degradation test. The work suggests the potential applicability of the developed flexible and eco-friendly humidity sensor in wearable healthcare devices and other humidity sensing applications.

Olive stone powder filled bio-based polyamide 5.6 biocomposites: biodegradation in natural soil and mechanical properties

The extensive use of non-biodegradable and petroleum derived polymers in industry exacerbates environmental problems associated with plastic waste accumulation and fossil resource depletion. The most promising solution to overcome this issue is the replacement of these polymers with biodegradable and bio-based polymers. In this paper, novel biocomposites were prepared from bio-based polyamide 5.6 (PA56) with the addition of olive stone powder (OSP) at varying weight concentrations by melt compounding method. The degradability of the prepared biocomposites is investigated through soil burial test, and assessed by reduction in their mechanical properties. The biodegradability of bio-based polyamide 5.6 is shown to be improved by addition of olive stone powder, and its effects on the properties of polymer matrix are elucidated. The Fourier transform infrared (FTIR) spectrum of the biocomposites indicate the successful incorporation of OSP into PA56 polymer matrix. After six-month soil burial test, scanning electron microscopy and FTIR show the degradation of PA56 through morphological and structural changes, respectively. Differential scanning calorimetry reveals the changes in the transition temperatures of the polymer matrix and an increase in crystallinity. Thermogravimetric analysis is used on the biocomposite to determine the fraction of its components, polymer and biofiller, and the results show that 2.67% (w/w) of the polyamide 5.6 is biodegraded at the end of the six-month soil burial.