Search Results (109)

The burgeoning convenience food sector, particularly in China, has intensified demand for packaging that simultaneously delivers convenience, environmental sustainability, and functional performance. This study addresses this need by developing a novel self-sealing, rapidly soluble food packaging film. The film was prepared using solvent casting technology, with a konjac glucomannan (KGM) matrix as the base material and gelatin (Gel) and hydroxypropyl tapioca starch (HS) as reinforcing agents. Leveraging the thermoplastic effect of HS (its hydroxypropyl side chains disrupt the ordered hydrogen bond network of KGM and Gel, enhancing molecular chain mobility) characterization via FTIR and SEM confirmed successful heat-sealing upon HS incorporation, while dissolution testing validated enhanced dissolution kinetics. The optimal formulation (KGH₃) exhibited superior mechanical properties (tensile strength (TS): 17.54 MPa) and excellent barrier performance against both light and oxygen transmission compared to pristine KGM and KG control films. Self-sealed pouches fabricated from KGH films preserved edible oil for 65 days, maintaining peroxide values within acceptable limits and demonstrating 48.7% reduction in oxidation compared to KG films. These findings establish KGM–Gel–HS film as promising candidates for adhesive-free, biodegradable packaging of lipid-rich foods. Full article

To address the hazards posed by formaldehyde emissions from wood-based products to human health and the indoor environment, research on wood adhesives has focused on developing green and eco-friendly alternatives. However, the limited water resistance and bonding strength of bio-based or glyoxal-based adhesives have hindered their practical application. In this work, a co-condensation method was employed to prepare glyoxal-based co-condensation adhesive incorporating starch and a small amount of chitosan as synergistic reinforcing agents to enhance their cross-linking extent. Considering cost control, the starch content was varied to adjust the adhesive properties. When the molar ratio of glyoxal to urea was 2:1 and the mass ratio of starch to urea was 0.5:1, the adhesive exhibited optimal bonding strength, reaching 1.48 MPa after immersion in cold water for 24 h and 0.91 MPa after treatment in 63 °C hot water for 3 h. These values exceeded the requirements of the Chinese national standard (GB/T 9846-2015, ≥0.7 MPa). Structural analysis indicated Schiff base and aldol condensation reactions among amino groups in chitosan and urea and hydroxyl and aldehyde groups in starch and glyoxal, forming chemical covalent cross-links that contributed to improved water resistance and bonding strength of plywood samples. Furthermore, the excellent penetration ability of the adhesive could promote the formation of a uniform and dense cross-linked network under hot-pressing conditions, thereby enhancing the overall performance of the plywood. Full article

Biopolymer adhesives are moving toward frontline use in medicine and manufacturing as the limitations in some petrochemical systems, including cytotoxicity, challenges in wet adhesion for specific families of synthetic resins and formaldehyde emissions associated with amino-formaldehyde materials are becoming increasingly difficult to accept. This review integrates mechanisms, material classes and quantitative performance across biopolymer-based adhesives. We focus on architectures that combine permanent covalent anchoring with reversible, energy-dissipating bonds and on how functional group density, crosslink density, microstructure and additives act as design knobs for wet performance, durability and degradation. Across biomedical applications, chitosan, alginate, gelatin and related hydrogels achieve wet lap-shear strengths on the order of tens of kilopascals, cut liver-bleeding times by roughly half, provide strong antibacterial activity and close diabetic wounds by about 92 percent by day 14. Thermoresponsive alginate–gelatin sealants exceed clinically relevant burst pressures and microneedle patches withstand more than 120 mmHg while sealing arteries in under a minute. In industrial settings, dialdehyde-based starch resins deliver 0.83 to 1.05 MPa dry shear and maintain strength after water immersion while meeting stringent emission classes, and silane-modified nanocellulose in urea–formaldehyde markedly reduces free formaldehyde without sacrificing the internal bond. We conclude by identifying priorities for standardized wet testing, and lifetime matching of strength and degradation that can support large-scale clinical and industrial translation. Full article

Traditional fossil-based adhesives, hindered by issues such as formaldehyde emission, dependence on fossil resources, and poor biodegradability, struggle to meet the global demand for low-carbon green development. Biomass-based adhesives have thus emerged as a core alternative. Among them, chitin/chitosan derived from biomass waste such as shrimp and crab shells demonstrates significant potential in the adhesive field due to its renewability, controllable structure, biocompatibility, and inherent antibacterial properties. However, mainstream biomass adhesives like soy protein and starch adhesives suffer from poor water resistance and insufficient wet adhesion strength. Pure chitin/chitosan-based adhesive systems also exhibit low wet strength retention. Furthermore, the overall development faces challenges including high extraction costs, insufficient performance synergy, poor industrial compatibility, and a lack of standardized systems. This review follows the framework of “resource–extraction–modification–performance–application–challenges” to systematically summarize relevant research progress. It clarifies the molecular structure and intrinsic advantages of chitin/chitosan, outlines extraction processes such as acid/alkali and enzymatic methods, and characterization techniques including FT-IR and XRD. The review focuses on analyzing modification strategies such as composite modification, chemical modification, biomineralization, and biomimetic design, and verifies the application potential of these adhesives in wood processing, biomedicine, paper-based packaging, and other fields. Research indicates that chitin/chitosan-based adhesives provide an effective pathway for the green transformation of the adhesive industry. Future efforts should concentrate on developing green extraction processes, designing multifunctional integrated systems, and achieving full resource utilization of biomass. Additionally, establishing comprehensive standardized systems and promoting the translation of laboratory research into industrial applications are crucial to driving the industry’s green transition. Full article

Thermoplastic starch (TPS) blended with biodegradable polyesters such as polyhydroxybutyrate (PHB), polylactic acid (PLA), polybutylene succinate (PBS), and polycaprolactone (PCL) represents a promising route toward sustainable alternatives to petroleum-based plastics. TPS offers advantages related to abundance, low cost, and biodegradability, while polyesters provide improved mechanical strength, thermal stability, and barrier performance. However, the intrinsic incompatibility between hydrophilic TPS and hydrophobic polyesters typically leads to immiscible systems with poor interfacial adhesion and limited performance. This review critically examines recent advances in the development of TPS/polyester blends, with emphasis on compatibilization strategies based on chemical modification, natural and synthetic compatibilizers, bio-based additives, and reinforcing agents. Particular attention is given to the role of organic acids, essential oils, phenolic compounds, nanofillers, and natural reinforcements in controlling morphology, crystallinity, interfacial interactions, and thermal–mechanical behavior. In addition, the contribution of bioactive additives to antimicrobial and antioxidant functionality is discussed as an emerging multifunctional feature of some TPS/polyester systems. Finally, current limitations related to long-term stability, scalability, and life cycle assessment are highlighted, identifying key challenges and future research directions for the development of advanced biodegradable materials with tailored properties. Full article

The fiberboard industry remains heavily reliant on synthetic, formaldehyde-based adhesives, which, despite their cost-effectiveness and strong bonding performance, present significant environmental and human health concerns due to volatile organic compound (VOC) emissions. In response to growing sustainability imperatives and regulatory pressures, the development of non-toxic, renewable, and high-performance bio-based adhesives has emerged as a critical research frontier. This review, conducted through both narrative and systematic approaches, synthesizes current advances in green adhesive technologies with emphasis on lignin, tannin, starch, protein, and hybrid formulations, alongside innovative synthetic alternatives designed to eliminate formaldehyde. The Evidence for Policy and Practice Information and Coordinating Centre (EPPI) framework was applied to ensure a rigorous, transparent, and reproducible methodology, encompassing the identification of research questions, systematic searching, keywording, mapping, data extraction, and in-depth analysis. Results reveal that while bio-based adhesives are increasingly capable of approaching or matching the mechanical strength and durability of urea–formaldehyde adhesives, challenges persist in terms of water resistance, scalability, cost, and process compatibility. Hybrid systems and novel crosslinking strategies demonstrate particular promise in overcoming these limitations, paving the way toward industrial viability. The review also identifies critical research gaps, including the need for standardized testing protocols, techno-economic analysis, and life cycle assessment to ensure the sustainable implementation of these solutions. By integrating environmental, economic, and technological perspectives, this work highlights the transformative potential of green adhesives in transitioning the fiberboard sector toward a low-toxicity, carbon-conscious future. It provides a roadmap for research, policy, and industrial innovation. Full article

Background: Postoperative abdominal adhesions are a common and serious complication following abdominal surgery, often leading to chronic pain, bowel obstruction, or infertility. This study aimed to evaluate the efficacy of the new starch-based absorbable hemostatic agent and dressing, BioSight, in comparison with a predicate device (4DryField^® PH) for the prevention of abdominal adhesions in a rat model. Methods: A total of 90 Sprague–Dawley rats were used to establish an intra-abdominal adhesion model and assigned to the BioSight, 4DryField^® PH, or control group. Standardized injuries were created on the cecum and parietal peritoneum, followed by application of the designated materials. Animals were sacrificed at 2, 4, and 12 weeks for macroscopic adhesion scoring and histopathological evaluation. Adhesion area, adhesion strength, and tissue thickness were assessed using established scoring systems, and local healing was examined by H&E staining. All quantitative data were analyzed using one-way ANOVA. Conclusions: In a rat peritoneal adhesion model, BioSight exhibited pronounced anti-adhesion efficacy comparable to 4DryField^® PH. Macroscopic evaluation showed consistently low adhesion scores (≤0.4) across all time points up to 12 weeks, while histological analysis confirmed reduced adhesion thickness, with BioSight displaying numerically lower values, particularly at early stages (251.3 ± 137.4 µm vs. 323.2 ± 174.6 µm at Week 2). This performance is attributed to rapid in situ hydrogel formation that provides effective temporary tissue separation, limits early fibrin deposition and inflammatory cell infiltration, and supports hemostasis. Importantly, the starch-based hydrogel exhibits a balanced biodegradation profile—persisting long enough to protect injured tissues during the critical inflammatory and fibroproliferative phases, yet undergoing complete enzymatic resorption thereafter without adverse tissue reactions. Collectively, these results highlight the anti-adhesion functionality of BioSight and support the clinical potential of plant-derived starch-based bioresorbable surgical adjuncts. Full article

Reversible adhesives enable temporary yet robust bonding between surfaces, allowing controlled detachment without structural or interfacial damage. This capability is gaining increasing recognition as a crucial requirement for sustainable technologies, where repairability, reusability, and minimal waste are key objectives. Among the diverse strategies explored for reversible adhesion (including supramolecular assemblies, bioinspired dry adhesives, and stimuli-responsive polymers), hydrogel-based systems have emerged as particularly versatile candidates due to their tunable mechanics, elasticity, and intrinsic biocompatibility. Recent studies highlight the use of renewable or biodegradable polymers to develop sustainable, water-rich hydrogel networks with controllable adhesive properties, minimizing environmental impact while maintaining performance. Despite these advances, significant challenges still hinder full implementation: biopolymer-based systems such as chitosan or starch often exhibit strong but poorly controllable adhesion, compromising reversibility and reusability. This review provides a comprehensive overview of strategies for developing hydrogel-based reversible adhesives, focusing on sustainable material selection, molecular design principles, and the underlying mechanisms of bonding and debonding. Furthermore, characterization methodologies, from conventional mechanical testing to surface-sensitive and dynamic techniques, are discussed in detail to establish structure–property–function relationships. Finally, emerging directions and application opportunities are outlined, offering a framework for the rational design of next-generation, sustainable adhesive systems. Full article

This study investigates the application effects of p-toluenesulfonic acid (p-TsOH) as an efficient catalyst in the esterification reaction of starch–citric acid adhesives, aiming to successfully prepare plywood with good water resistance through lower hot-pressing temperatures. By precisely controlling the addition ratio of pTSA (0–10%), the multifaceted impacts on the adhesive’s curing behavior, bonding strength, water resistance, thermal stability, and microstructure were analyzed. The results demonstrate that pTSA substantially catalyzes the esterification crosslinking reaction between starch and citric acid. Differential scanning calorimetry (DSC) analysis reveals a significant reduction in the reaction peak temperature from 197.7 °C to 154.3 °C, which effectively lowers the hot-pressing temperature and provides more energy-efficient processing conditions for plywood production. When pTSA addition is within the range of 6–8%, the adhesive exhibits superior bonding performance and water resistance. Moreover, thermal stability is significantly enhanced and the microstructure becomes denser, collectively improving the overall performance of the plywood. This study not only provides a solid theoretical basis for the development of high-performance, environmentally friendly, starch-based wood adhesives but also offers strong technical support for the practical application of related technologies expected to promote the green and sustainable development of the wood adhesive industry. Full article

In the present work, a new bio-sourced adhesive system based on deep eutectic solvent-modified lignin and oxidized starch (OSTL) resin is presented. For this purpose, unmodified and choline chloride–Zinc chloride (ChCl–ZnCl₂) deep eutectic solvent modified lignin at different contents (10%, 20%, and 30%) were used to prepare the OSTL resin. Ammonium persulfate (APS) was the oxidizer employed for the oxidation of starch, and urea was used as a low cost and effective crosslinker agent in the OSTL resin. FTIR analysis indicated that the content of carboxyl and carbonyl groups changed after the curing of the OSTL resin compared to oxidized starch (OST). DSC analysis indicated that the curing temperature of the OSTL resin containing DES-modified lignin was lower than that for unmodified lignin. Also, greater dimensional stability and mechanical strength could be achieved by increasing the amount of DES-treated lignin in the OSTL wood adhesive from 10 to 30 wt%. Based on the findings of this research, the physical and mechanical properties of the particleboard panels bonded with this type of bio-adhesive were acceptable according to the relevant standards. Additionally, urea can thus be used as a good cross-linker, not only to crosslink just OST, but also to connect DES-modified lignin and oxidized starch molecules. Under the conditions used, particleboards bonded with an oxidized starch–urea–pristine lignin adhesive presented decreasing internal bond (IB) strength with an increasing proportion of lignin. Conversely, when the same adhesive using DES-modified lignin was used, the internal bond (IB) strength improved with the increasing proportion of DES-modified lignin. At 30% proportions of lignin, the oxidized starch–urea–DES-modified lignin presented a 27% improvement in strength. Finally, it can be noted that this work brings a new insight to the development and application of lignin-based bio-adhesives to bond wood-based panels. Full article

The retention of polyphenols in thermally processed noodles is constrained by interactions with starch and glutenin, critically impacting functional properties (antioxidant activity, starch digestibility modulation) and quality attributes. Current understanding lacks quantitative links between initial pomace particle size, polyphenol behavior throughout processing, and the resulting noodle properties. This study systematically investigated how Rosa roxburghii pomace particle size (0.1–250 μm), fractionated into five ranges, governs polyphenol extractability, retention in fresh/boiled noodles, and their functional and quality outcomes. Mathematical modeling established quantitative particle size–property relationships. The results indicated that polyphenol release was maximized at the 1–10 μm particle size. Total phenolic retention in boiled noodles was highest with 0.1–1 μm pomace, while the retention of specific phenolics peaked with 60–80 μm pomace. Fresh noodle hardness and gumminess decreased significantly, particularly with extracts from 1 to 40 μm pomace, whereas boiled noodles showed increased chewiness/adhesiveness. All polyphenol-enriched noodles exhibited suppressed starch digestibility and enhanced antioxidant capacity. Robust quadratic regression models predicted key properties based on particle size. Molecular interactions (hydrogen bonding, hydrophobic contacts, π–cation stacking, salt bridges) between key phenolics (EGCG, hydroxybenzoic acid, gallic acid, quercetin, and isoquercitrin) and the gluten–starch matrix, critically involving residues Arg-86 and Arg-649, were identified as the underlying mechanism. These results demonstrate that precise control of pomace particle size regulates extract composition and molecular binding dynamics, providing a strategic approach to optimize functional noodle design. Full article

Superhydrophobic surfaces, characterized by water contact angles greater than 150°, have attracted widespread interest due to their exceptional water repellency and multifunctional applications. However, traditional fabrication methods often rely on fluorinated compounds and petroleum-based polymers, raising environmental and health concerns. In response to growing environmental and health problems, recent research has increasingly focused on developing green superhydrophobic surfaces, employing eco-friendly materials, energy-efficient processes, and non-toxic modifiers. This review systematically summarizes recent progress in the development of green superhydrophobic materials, focusing on the use of natural substrates such as cellulose, chitosan, starch, lignin, and silk fibroin. Sustainable fabrication techniques, including spray coating, dip coating, sol–gel processing, electrospinning, laser texturing, and self-assembly, are critically discussed with regards to their environmental compatibility, scalability, and integration with biodegradable components. Furthermore, the functional performance of these coatings is explored in diverse application fields, including self-cleaning, oil–water separation, anti-corrosion, anti-icing, food packaging, and biomedical devices. Key challenges such as mechanical durability, substrate adhesion, and large-scale processing are addressed, alongside emerging strategies that combine green chemistry with surface engineering. This review provides a comprehensive perspective on the design and deployment of eco-friendly superhydrophobic surfaces, aiming to accelerate their practical implementation across sustainable technologies. Full article

Compatibilizers that enhance sustainability and improve the miscibility of polymer blend components have garnered significant attention. This study investigates the difference between the synthetic chain extender Joncryl^® ADR 4468 and the natural epoxidized linseed oil (ELO) Merginat 8510100 as compatibilizers for thermoplastic starch/poly (butylene succinate) (TPS/PBS) blends. Blends containing 40% TPS and 60% PBS were prepared with 1, 3, and 5 phr of each compatibilizer, along with a reference with no additives. The properties of these blends were evaluated using tensile testing, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), rheology, and scanning electron microscopy (SEM). The findings indicate that while Joncryl^® ADR 4468 significantly improved tensile strength, it also resulted in a brittle fracture. In contrast, ELO batches exhibited greater ductility, albeit with lower tensile strength. These differences are attributed to the chain extension and minor cross-linking effects of Joncryl^® ADR 4468, compared to the increased chain mobility arising from ELO’s plasticizing and compatibilizing actions. Supporting evidence for these observations includes increased cold crystallization temperature (T_cc) and melting temperature (T_m), greater storage modulus along with higher complex viscosity, strengthened interfacial adhesion, and fewer morphological defects in Joncryl^® ADR 4468 blends. These results highlight the importance of selecting an appropriate compatibilizer based on specific application requirements. Overall, this study addresses the knowledge gap regarding the loadings of Joncryl^® ADR 4468 and ELO in TPS/PBS blends and provides a basis for further optimization strategies, such as the incorporation of binary compatibilizers, alternative grafting-based compatibilizers, and twin-screw blending modifications. Full article

This study investigates the use of suberinic acid residues (SARs), derived from birch outer bark, as a bio-based additive in high-density fiberboard (HDF). Boards with target densities of 800 kg m⁻³ were produced with SAR contents of 0, 1, 5, 10, 20, and 50%. Standardized tests evaluated mechanical properties: screw withdrawal resistance, modulus of elasticity, modulus of rupture, and internal bond, as well as moisture resistance through surface water absorption, water absorption, and thickness swelling. Density profiles were also analyzed. SAR content influenced HDF performance in a concentration-dependent manner. The most notable improvements in mechanical properties occurred at 5% SAR, where fine particles likely enhanced internal bonding and stiffness. However, higher SAR levels led to reduced mechanical strength, possibly due to an excessive particle surface area exceeding the adhesive’s bonding capacity. Moisture resistance declined with increased SAR, attributed to its hydrophilic nature and process parameters, although SAR-modified boards still outperformed those with other biodegradable additives like starch. SAR also affected the density profile, improving core densification at moderate levels. Overall, SAR shows potential as a renewable additive for enhancing HDF performance, particularly at low concentrations, balancing mechanical strength and environmental benefits. Full article

Potato starch noodles (PSN), a characteristic gluten-free Asian food, are essentially high-concentration starch gels (about 35% starch) formed through gelatinization and retrogradation. This study systematically investigates freezing temperature effects, particularly across the glass transition temperature, on PSN texture and microstructure. We found that fresh PSN have a freezing point of −1 °C, supercooling temperature of −4.5 °C, and a T_g’ value of −3.1 °C. Freezing significantly reduced the adhesiveness of PSN and increased the hardness. During the 48 h freezing process, noodles frozen at −3 °C, the closest to T_g’, exhibited the highest hardness (14,065.77 g), springiness (0.98), cohesiveness (0.93), chewiness (11,971.06), and resilience (0.84), and the least adhesiveness. PSN frozen within the range near T_g’ (−3 °C) showed superior texture, continuous solid cross-section, and dense surface, attributed to the reverse transformation of starch, high mobility of starch chains, and smaller ice crystals. PSN frozen at −3 °C for 24 h displayed the most compact and desirable texture compared to the other samples. These findings deepen the understanding of the role of glass transition temperature in the texture formation of starch gel during freezing and provide valuable insights for optimizing the frozen processing of starch gel-based food. Full article