Soy protein adhesives with water and heat resistant, and magnetic properties via micron/nanometer iron-based particle modification

Cao, J., Chen, C., and Xu, W. (2026). "Soy protein adhesives with water and heat resistant, and magnetic properties via micron/nanometer iron-based particle modification," BioResources 21(1), 873–889.

Abstract

The development of soybean meal (SM)-based adhesives with water resistance, heat tolerance, and magnetic-adsorbent functions is critical for expanding their applications as wood adhesives in hot and humid kitchen environments. A key goal is to enable magnetic storage systems such as knife holders and detachable shelves through localized adhesive application. However, the monofunctionality of existing bio-based adhesives limits their practical potential. In this study, micron-sized carbonyl iron powder (CIP) and nanoscale ferrosoferric oxide (Fe₃O₄) were introduced to confer multifunctionality to SM adhesives. Results indicated that the micron-scale dispersion of CIP markedly enhanced the heat resistance and wet-heat stability of SM adhesives through physical barrier effects, while optimizing magnetic attraction efficiency. In contrast, Fe₃O₄ nanoparticles achieved rapid magnetic response at low additive levels due to their high saturation magnetization, though nano-aggregation caused a sharp viscosity increase. Scenario-based validation confirmed that CIP-modified adhesives exhibit excellent structural stability in hot and humid kitchen environments, and they could withstand steam exposure, and retain magnetic adsorption properties.

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Full Article

**Soy Protein Adhesives with Water and Heat Resistant, and Magnetic Properties via Micron/Nanometer Iron-based Particle Modification**

Jiawen Cao, Chen Chen, and Wei Xu *

DOI: 10.15376/biores.21.1.873-889

Keywords: SM adhesive; CIP; Fe₃O₄ nanoparticles; Multifunctionality; Bioadhesive

Contact information: College of Furnishings and Industrial Design, Nanjing Forestry University Nanjing, Jiangsu, China; *Corresponding author: xuwei@njfu.edu.cn

Graphical Abstract

INTRODUCTION

Adhesives play a pivotal role in various industries, ranging from construction and automotive to electronics and packaging (Shin et al. 2024; Ciardiello et al. 2025; García-Moreno et al. 2025; Shi et al. 2025). Traditional synthetic adhesives, while effective, often raise environmental concerns due to their petroleum-based origins and non-biodegradable nature. In recent years, there has been a growing interest in developing sustainable, eco-friendly adhesives derived from renewable resources (Bai et al. 2024; Fan et al. 2024; Yang et al. 2025). Among these, soy-based adhesives have emerged as a promising alternative due to their biodegradability, low cost, and abundant availability (Chen et al. 2024; Hou et al. 2025). Soy proteins, particularly those derived from defatted soy flour, have been extensively studied for their adhesive properties (Zhang et al. 2024).

However, the inherent limitations of soy-based adhesives, such as relatively low water resistance and mechanical strength, have prompted researchers to explore various modification strategies to enhance their performance (Bai et al. 2024). One such strategy involves the incorporation of polyamidoamine-epichlorohydrin (PAE) resin, a widely used cross-linking agent that can significantly improve the water resistance and bond strength of soy-based adhesives (Chang et al. 2024; Kan et al. 2024). The curing mechanism involves water evaporation and chemical cross-linking between PAE and soybean protein. Under heating conditions, the PAE resin reacts with amino and hydroxyl groups in soy protein to form a covalently cross-linked network, thereby enhancing the adhesive’s durability and mechanical properties (Mi et al. 2023; Kan et al. 2025; Grossi et al. 2025). Additionally, the combination of high-temperature and low-temperature defatted soy flour has been shown to optimize the adhesive properties by balancing the protein denaturation and functional group availability (Zheng et al. 2017; Yan et al. 2022).

In recent years, the development of multifunctional adhesives has emerged as a cutting-edge frontier in materials science, driven by demands for smart and responsive materials in advanced applications (Hu et al. 2024; Cao et al. 2025; Lima et al. 2025). Among these, magnetic adhesives have garnered significant attention due to their unique ability to interact with external magnetic fields, enabling innovative functionalities such as reversible adhesion, electromagnetic shielding, and smart assembly systems (Verna et al. 2013; Wang et al. 2022; Sha et al. 2023). For instance, magnetic adhesive-enabled substrates could serve as reconfigurable mounting platforms for small objects (e.g., children’s toys, office supplies, or kitchen utensils), combining structural bonding with on-demand magnetic attachment. To realize such dual functionality, a systematic investigation into the individual effects of magnetic fillers—specifically carbonyl iron powder (CIP) and Fe₃O₄ nanoparticles—within bio-based adhesive matrices is critical. It is worth noting that kitchen environments have stringent requirements for adhesives compared to office and children’s daily activity spaces, including exposure to fumes (70 °C), steam (100 °C) and humidity fluctuations (48 to 56% RH) (Xu et al. 2023; Xin et al. 2024).While epoxy resin-based magnetic adhesives incorporating carbonyl iron powder (CIP) exhibit thermal decomposition starting at 375 °C , their petroleum-derived nature and excessive thermal tolerance mismatch practical kitchen demands. This highlights the need for bio-based alternatives that balance functional performance with sustainability (You 2013).

To realize such dual functionality in eco-friendly systems, a systematic investigation into the individual effects of magnetic fillers—specifically CIP and Fe₃O₄ nanoparticles—within bio-based adhesive matrices is critical. In this study, micro-scale CIP (5 μm) and nano-scale Fe₃O₄ (20 nm) are introduced as independent control groups. CIP, which is characterized by high magnetic permeability and low coercivity, was selected due to its ability to provide robust bulk magnetization (Zhang et al. 2023; Peng et al. 2025). Fe₃O₄ nanoparticles exhibit superparamagnetic behavior and a high specific surface area, while the Fe³⁺ ions on their surface can enhance the bonding performance of PAE-modified soy-based adhesives by forming coordination bonds with amino and hydroxyl groups in the cross-linking network (Mi et al. 2023). To suppress aggregation, CIP and Fe₃O₄ were modified with KH-550 (γ-aminopropyl triethoxysilane) and polyacrylic acid (PAA), respectively, ensuring uniform dispersion while strengthening interfacial adhesion (Zhang 2005; You 2013; Song et al. 2022). This surface engineering not only ensures homogeneous dispersion, but also thermal degradation of PAA-modified Fe₃O₄ up to a temperature of 150 to 200 °C (Wang et al. 2024). Through decoupling the magnetic and mechanical impacts of these fillers, the present work establishes a foundational framework for designing hybrid bio-adhesives tailored to multifunctional kitchen applications.

This study systematically investigates the effects of micro-scale carbonyl iron powder (CIP) and nano-scale Fe₃O₄ nanoparticles on the bonding strength, water resistance, thermal stability, and magnetic responsiveness of SM adhesives, aiming to address the functional demands of bio-based adhesives in high-humidity and high-temperature kitchen environments (e.g., steam-exposed cutting boards and magnetic storage racks). Through incorporating CIP and Fe₃O₄, Fourier-transform infrared (FTIR) spectroscopy was employed to better understand filler-matrix interfacial interactions, elucidating the synergistic mechanisms between magnetic functionality and adhesive performance. This study focused on developing an adhesive that combines moisture and heat resistance with magnetic adsorption properties. Used as a bonding agent between wood veneers, it enables the production of magnetically adsorbent plywood. This facilitates the creation of magnetic furniture with customizable layouts and stable fixation, such as magnetic knife racks and removable storage modules for kitchen magnetic storage systems. Through the synergistic optimization of interface engineering and particle size effects, this work provides theoretical insights for designing bio-based adhesives tailored to complex humid/thermal environments, facilitating the transition of green materials from laboratory research to practical applications.

EXPERIMENTAL

Materials

The low-temperature defatted soybean meal (LSM) (protein content: 51.4%) and high-temperature defatted soybean meal (HSM) (protein content: 48.7%) were purchased from Anyang Wanhui Bio-technology Co. The PAE resin had a solids content of 13.33%, a pH of 3.98, and a viscosity of 84 mPa·s. It was supplied by Zhejiang Shenghua Yunfeng Holding Group Co., Ltd. Carbonyl iron powder was purchased from Guangzhou Metal Metallurgy Group Co., Ltd., with a particle size of 5 μm. The silane coupling agent KH550 was purchased from Kangjin New Material Technology Co. Tri-iron tetraoxide nanoparticles were purchased from Aladdin Holding Group with a particle size of 20 nm, and PAA was purchased from Shandong Linyi Bangpu Import and Export Co. Eucalyptus veneer (300 mm × 300 mm × 3 mm, moisture content 12% to 14%) was provided by Zhejiang Shenghua Yunfeng Holding Group Co.

Preparation of Magnetic Adhesive

Pretreatment of magnetic fillers

A total of 100 g of carbonyl iron powder pretreatment was weighed, it was configured in 250 mL KH-550 solution (the volume ratio of anhydrous ethanol to distilled water in the solvent is 10:1), and the amount of KH-550 in the added solution was 3% of the mass of carbonyl iron, respectively. The carbonyl iron powder was put into the mixture, and then the mixed solution was ultrasonically dispersed in a water bath at 40 °C with mechanical stirring for 30 min. The mixture was then left to stand for 24 h after completion, so that the KH-550 and the carbonyl iron powder particles could fully react. Finally, the system was placed in a drying oven at 80 °C, dried, and sealed for spare parts (You 2013).

A total of 100 g of Fe₃O₄ nanoparticles was weighed, 10 g of PAA was added to it, and then it was poured into the appropriate amount of demineralized water, next ultrasonic dispersion by ultrasonic cleaner was performed for 10 min, and finally the system was put into the drying box at 60 °C, dried and sealed for spare material preparation (Song et al. 2002; Zhang 2005).

Adhesive preparation

The LSM and HSM were blended at a 2:3 mass ratio to prepare composite SM. The PAE resin was diluted to 7% solid content with deionized water. The SM, PAE solution, and magnetic fillers (CIP/Fe₃O₄) were mixed in varying mass ratios under mechanical stirring for 5 min. The formulas are shown in Table 1.

Table 1. Various Adhesive Formulations

Preparation of Three-ply Plywood

The SM adhesive was uniformly applied to both sides of the eucalyptus core veneer at a spread rate of 260 g/m². The assembly (core veneer with adhesive and two unglued face veneers) was aligned along the wood grain direction, pre-pressed at 1.3 MPa for 40 min, then hot-pressed at 120 °C and 1.2 MPa for 20 min to fabricate three-ply plywood.

Determination of Adhesive Viscosity

The viscosity of the adhesive was measured using NDJ-1 viscometer (Zhejiang, China). Sampling was according to the Chinese national standard GB/T 2794 (2022). Provisions of the sampling involved stirred to ensure the representativeness of the sample. The number of units to be taken was basically kept the same; in each case, a sufficient amount was collected to accommodate three tests. Additional mixture was retained, as needed, for additional testing.

Water Resistance Test

Plywood water resistance was evaluated according to GB/T 2794 (2022). After conditioning at room temperature for ≥ 24 h, 12 specimens (2.5 cm × 10 cm) were cut from each panel.

Dry strength was tested directly using a UTM 6000 universal testing machine (Shenzhen, China).

Category II wet strength: Specimens were immersed in 63 ± 3 °C water for 3 h, cooled for 10 min, then tested.

Category I wet strength: Specimens were boiled for 4 h, dried at 63 ± 3 °C for 20 h, re-boiled for 4 h, cooled in room-temperature water, then tested.

Fourier Transform Infrared Spectroscopy (FTIR)

The prepared adhesives were cured in an oven at 120 °C and ground into powder. The cured magnetic adhesive powder was tested by KBr pressing method using a VERTEX 80V FTIR spectrometer (Bruker, Germany) with a scanning wave number of 4000 to 400 cm^-1, resolution of 4 cm^-1 and 32 scans.

Thermal Performance Test

Thermal stability was evaluated using a TGA 209F3 thermogravimetric analyzer (NETZSCH, Germany). Samples for TGA analysis were prepared from the adhesives that had been cured in an oven at 120 °C and ground into powder. Subsequently, portions weighing 0.0050 to 0.0100 g were loaded into TGA aluminum pans and heated from 25 to 650 °C at a rate of 20 °C/min under a nitrogen atmosphere with a flow rate of 40.0 mL/min. The relationship of the change of the system quality (w%) was obtained at each temperature (T).

Magnetic Absorption Test

Square plywood specimens (20 mm × 20 mm, n = 10 per group) were cut and deburred. Standardized neodymium iron boron (NdFeB) magnets (20 mm × 10 mm × 2 mm) were vertically contacted with the specimen surface on a non-magnetic platform. As shown in Fig. 1, the plywood specimen was placed flat on a non-magnetic platform. The test commenced with a single magnet being vertically brought into contact with the sample surface and then gently released. If adhesion was maintained, magnets were added incrementally until the maximum number that could be stably held was identified.

Fig. 1. Magnetic adsorption test diagram

RESULTS AND DISCUSSION

Flow and Viscosity Analysis of Fresh Adhesives

Proper fluidity is a prerequisite for the adhesive to be able to wet and penetrate the veneer surface and finally form mechanical interlocks to achieve bonding. As shown in Fig. 2, increasing Fe₃O₄ loading markedly raised adhesive viscosity and reduced fluidity; for CIP, there was no marked change in the fluidity. The surface of CIP was treated with a coupling agent, and because of its large particle size and low specific surface area, it was uniformly dispersed in the substrate, and it had good interfacial compatibility with the PAE resin-defatted soybean meal matrix. Therefore, it was able to maintain proper adhesion even if the addition amount was increased to 65 g, which is a prerequisite for wetting and penetrating the veneer surface. Even at that addition level, it still maintained suitable fluidity without marked changes. In contrast, although Fe₃O₄ nanoparticles were also modified with coupling agents, their nanoscale size, magnetic interactions, and high specific surface area resulted in particles that were prone to agglomeration (Zhang et al. 2021), and the formation of the network structure markedly increased the viscosity of the system and decreased the fluidity markedly, especially when the amount of the additive was more than 25 g.

Fig. 2. Adhesive fluidity

Tables 2 and 3 show the effects of CIP and Fe₃O₄ loadings on adhesive viscosity and solids content. As far as the applicability of adhesive technology is concerned, the viscosity range of adhesives used for wood lamination should be between 5,000 and 25,000 mPa∙s (Zhang et al. 2021; Xu et al. 2022). The viscosity of the SM-CIP system increased with CIP addition from 11,909 to 47,550 mPa∙s, and it still remained in the wood-laminating adhesives in the ≤ 45 g addition. The uniform dispersion of micron-sized particles and surface hydrophobicity modification effectively slowed down the sharp increase in viscosity; the solid content was linearly increased from 23.4% to 68.0%, indicating that the high loading capacity of the CIP was compatible with the substrate. Thus, the recommended dosage is 35 to 45 g. The viscosity of SM-Fe₃O₄ system soared from 11,900 to 72,600 mPa∙s with nanoparticle loadings approaching the upper limit of the process only at loading ≤ 15 g. Nanoclusters markedly degraded the fluidity at high loadings; the increase in solids content was slower, and a maximum loading of ≤ 15 g is recommended to avoid processing failures. The micrometer size of CIP balanced viscosity and functionality through physical filling and interfacial bonding, while the nano-effect of Fe₃O₄ limited its window of applicability due to the tendency of agglomeration.

Table 2. Viscosity and Solid Content of the SM-CIP Adhesive

Table 3. Viscosity and Solid Content of the SM-Fe₃O₄ Adhesive

Water Resistance Analysis of Adhesives

Figure 3A and B show the results of tensile shear strength tests of plywood prepared with different adhesives under dry state and hygrothermal conditions. For the SM-CIP adhesive (Fig. 3A), the dry strength initially increased with CIP loading, peaking at 1.86 MPa (45 g), then declined to 1.20 MPa. This suggests that the moderate dispersion of micrometer-sized CIP markedly enhanced the cross-linking density through the hydrophobic modification of the surface and the interfacial bonding, whereas the aggregation of particles at the high content led to the disruption of the continuity of the matrix. The category I wet strength decreased continuously from 0.88 to 0.50 MPa with the increase of CIP addition from 15 to 65 g, while the category II wet strength maintained a high level in the range of 25 to 45 g, indicating that the surface modification of CIP effectively suppressed the penetration of water molecules in the moderate addition. However, the interfacial defects were aggravated in the high content. Even at the high addition level of 55 g, the category II wet strength remained at 1.08 MPa (87.1% retention of dry strength), highlighting the robustness of its water resistance performance (Sadare et al. 2020).

In contrast, the dry state strength of SM-Fe₃O₄ adhesive (Fig. 3B) reached 1.65 MPa at 25 g (22.2% enhancement over the base SM), but plummeted to 1.09 MPa at 35 g, reflecting the negative effect of the agglomeration effect of the nanoparticles on the integrity of the adhesive layer. The water resistance showed marked differences: the category I wet strength decreased sharply with increasing addition (1.00→0.63 MPa, a 37% decrease), while the category II wet strength rose to 1.41 MPa at 25 g (up to 85.5% of the dry strength), but excessive addition still led to performance collapse (Zeng et al. 2022; Chen et al. 2023).

The lower category I wet tensile shear strength indicated limited resistance to prolonged boiling, suggesting that the current SM-based adhesives are suitable for interior applications.

Fig. 3. Gluing strength of different adhesives: (A) gluing strength of SM-CIP adhesive; (B) gluing strength of SM-Fe₃O₄ adhesive

Visual Appearance of Cured Adhesives

The prepared adhesives were cured in an oven at 120 °C. The base SM adhesive showed marked cracks (maximum crack density) in the adhesive layer due to the low solid content and moisture evaporation during curing, which was directly related to the pore structure due to the lack of hydrophobic components (Li et al. 2022). The introduction of functional particles markedly improved this defect. Figure 4 shows that crack density in the SM-Fe₃O₄ system decreased progressively from severe (15 g) to negligible (35 g).

Fig. 4. Visual appearance of different cured adhesives

In contrast, the SM-CIP system achieved a completely crack-free adhesive layer at 45 to 65 g of loadings, and only microcracks are present at 25 to 35 g. The optimization effect was marked. For trace cracks, the optimization effect was markedly better than that of the Fe₃O₄ system.

FTIR Analysis

Infrared spectra of Fig. 5A (SM-CIP adhesive) and Fig. 5B (SM-Fe₃O₄ adhesive) reveal the differential effect of additives on the chemical structure of the adhesive. The FTIR spectra of SM-CIP adhesive were analyzed in the range of 3427 cm^-1 (O-H/N-H stretching vibrations), 2927 cm^-1 (-CH symmetry vibration), 1641 cm^-1 (amide I, C=O stretching vibration), 1532 cm^-1 (amide II, N-H bending/C-N stretching, and 1046 cm^-1 (C-O/C-N stretching vibration) and showed characteristic peaks, in which the vibration amplitudes at 1641 cm^-1, 1532 cm^-1, and 1046 cm^-1 were markedly enhanced with the increase of CIP addition (Rad et al. 2015; Zhang et al. 2021; Li et al. 2022; Chen et al. 2023).

Fig. 5. FTIR spectra of different adhesive samples: A: a (SM), b (SM-CIP-15), c (SM-CIP-25), d (SM-CIP-35), e (SM-CIP-45), f (SM-CIP-55), g (SM-CIP-65); B: a (SM), b (SM-Fe₃O₄-15), c (SM-Fe₃O₄-25), d (SM-Fe₃O₄-35)

The chemical reaction between PAE and SM crosslinking is shown in Fig. 6. This suggests that the micron-sized particles of CIP promoted the cross-linking reaction between PAE resin and soybean flour matrix through surface modification, which strengthened the hydrogen bonding network and interfacial chemical bonding of the amide structure, and thus enhances the cross-linking density and structural stability. In contrast, the vibrational amplitude of SM-Fe₃O₄ adhesive at 1632 cm^-1 (amide I) increased with the increase of Fe₃O₄ content, but the peak position was shifted lower than that of SM-CIP (shifted from 1641 to 1632 cm^-1), and nanoparticles may have interfered with the electronic conjugation of C=O.

The continuous enhancement of SM-CIP at 1046 cm^-1 and the synergistic optimization of the amide structure (1532 cm^-1 amplitude enhancement) together support its excellent water resistance, whereas the shift of the amide I peak position and vibration amplitude of SM-Fe₃O₄ variations reflect the coexistence of interfacial cross-linking enhancement and structural defects brought about by the nano-effect. It is noted that directly quantifying new amide bonds from curing is complicated by the inherent amide signals from the soy protein.

The observed spectral changes are therefore attributed to the restricted molecular mobility and altered chemical environment resulting from a more densely cross-linked network formed between PAE and the soy protein matrix. This interpretation is consistent with the improved mechanical and water-resistant properties. In summary, the micron-scale dispersion of CIP effectively balanced functionality and structural integrity through surface modification, while the nanoparticle addition of Fe₃O₄ needs to further optimize the dispersion process to inhibit agglomeration and strengthen chemical bonding.

Fig. 6. Chemical reaction of PAE crosslinking with SM

Analysis of Thermal Properties of Adhesives

The thermal degradation process of SM adhesives is characterized by three stages: the first stage (room temperature ~210 °C) is mainly the escape of adsorbed and bound water; the second stage (210 to 250 °C) involves the thermal degradation of unstable soybean polysaccharide side chains and small molecules (oligosaccharides, free amino acids); and the third stage (250 to 600 °C) corresponds to the deeper decomposition of the protein skeleton structure and the crosslinked network of PAE resin (Chen et al. 2023; Li et al. 2023; Shan et al. 2024).

As shown in Fig. 7, the thermal behaviors were markedly altered after the introduction of CIP or Fe₃O₄: the initial decomposition temperatures of both SM-CIP and SM-Fe₃O₄ adhesives were greater than 150 °C, and the physical barrier formed by CIP through the micrometer-scale dispersion (degradation peak at 310 °C) slowed down the second-stage volatile fraction release. It also promoted the third-stage dense char layer formation (82.8% char residue), while Fe₃O₄ nanoparticles accelerated the second stage pyrolysis reaction (degradation peak temperature down to 299 °C) through high specific surface area and catalytic activity and achieved 67.8% char residue. This formulation was able to maintain interfacial stability over time in a high-temperature steam environment in a kitchen (typical temperature ≈100 °C).

Fig. 7. A: TG and DTG analyses of the SM-CIP adhesive; B: TG and DTG analyses of the SM-Fe₃O₄ adhesive

Analysis of Magnetic Attraction of Adhesives

Figure 8 shows the test method for magnetic adhesion. Table 4 lists the number of magnets required to achieve complete adsorption of wood blocks at different additive levels for SM-CIP and SM-Fe₃O₄ adhesives. The SM-CIP adhesive achieved stable magnetic attraction at high additive levels of 45 to 65 g through micron-scale physical filling and interfacial bonding (only 4 to 5 magnets), while SM-Fe₃O₄ adhesive achieved equivalent magnetic response (5 to 6 magnets) at a low additive level of 25 to 35 g by virtue of high saturation magnetization of nanoparticles and surface modification-enhanced interactions. For humidity resistance, modified SM-CIP (45 to 55 g) enabled humidity- and heat-resistant magnetic carriers in kitchens (60.34% solid content and 5-magnet shedding resistance), taking into account functionality, safety, and environmental adaptability.

Fig. 8. Test method for magnetic attraction

Table 4. Number of Fully Adsorbed Magnets for Different Adhesives

CONCLUSIONS

In this study, the differences in the properties of carbonyl iron powder (CIP) and nanoscale Fe₃O₄-modified soybean meal (SM) adhesives were systematically investigated to reveal the mechanisms of particle size effects and interfacial interactions on the comprehensive performance of the adhesives. The results showed that the micron-scale dispersion characteristics of CIP endowed the SM-CIP system with excellent flowability (21,500 to 24,700 mPa∙s at viscosities ≤ 45 g) and high char residue (82.8%). Its hydrophobic interfacial design effectively inhibited interfacial peeling under hot and wet environments (87.1% retention of Category II wet strength); whereas the Fe₃O₄’s nanoscale highly saturated magnetization property enabled the SM-Fe₃O₄ system to reach the viscosity standard (21,400 mPa∙s) at a low addition level (≤ 15 g) and achieve a sensitive magnetic response (5 to 6 magnets are required at 25 to 35 g), but they were limited by a sudden increase in viscosity due to nano-agglomeration (up to 72,600 mPa∙s at 35 g) with a degradation of hygroscopic strength (37% decrease in Category I wet strength).
Scenario-based analysis showed that the moisture-resistant SM-CIP (60.3% solids) met the hygrothermal stability needs of the kitchen scenario. The developed adhesive successfully served dual functions: as a structural binder for wood veneers in plywood manufacturing, and as a magnetic component enabling the resulting composite to function in magnetic storage applications. Combined with the filler-substrate interfacial bonding mechanism resolved by Fourier transform infrared (FTIR) spectrometry, this study provides a theoretical basis and technical paradigm for the multifunctionalized design and precise scenario-adaptation of biobased adhesives and promotes the expansion of the application of green adhesives in the fields of intelligent manufacturing and sustainable materials. The adhesives demonstrated potential for interior applications such as kitchen magnetic storage systems, though further optimization is needed for high-humidity exterior conditions. Meanwhile, the long-term stability and anti-settling properties of the fresh adhesive will be evaluated in subsequent studies.

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Article submitted: June 29, 2025; Peer review completed: July 26, 2025; Revised version received: November 7, 2025; Accepted: November 30, 2025; Published: December 10, 2025.

DOI: 10.15376/biores.21.1.873-889