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Herein origin and nucleation kinetics of transcrystalline layer (TCL) in bamboo fiber deposited with nano‐TiO2 (BF@TiO2)/polypropylene (PP) composite is studied. Firstly, the surface morphology, roughness, and energy, as well as crystalline structure (e. g., crystal face indices (hkl)) of BF@TiO2 are analyzed to clarify the origin of TCL in the composite. Subsequently, the nucleation kinetics of TCL in BF@TiO2/PP composite at different crystallization temperatures (Tc) are investigated through polarized optical microscopy. The results find that the surface roughness and energy of BF@TiO2 increase by 47.55 % and 2.41 % compared with untreated BF, respectively. Interestingly, the mismatch rates (MRs) of hkl(BF) vs. hkl(PP) are >320 %. In comparison, the MRs of (101)(BF@TiO2)TiO2 vs. (hkl)(PP) are dramatically decreased to <25 %, suggesting a similar crystal plane between BF@TiO2 and PP matrix. These results indicate that the TCL formation in the composite is more facile in BF@TiO2 than in the untreated BF. During isothermal crystallization, the nucleation and spherulite growth rates decrease as the Tc increases. The interface free energy difference (▵σ) between BF@TiO2 and PP is calculated based on the heterogeneous nucleation theory. The ▵σ is 1.54±0.11 J cm−2, highlighting that the BF@TiO2 strongly induces the PP nucleation. [ABSTRACT FROM AUTHOR]

Transcrystallinity (TC) developing on the fiber surface of natural fiber/semicrystalline polymer composites shows great application potential in interfacial enhancement. The local mechanical properties of TC play a vital role in understanding the interphase interaction mechanism. In this study, TC was firstly introduced in bamboo fiber-anchored nano-TiO2/polypropylene (PP) composite and subsequently the local mechanical properties of TC were measured in situ on nanoscale by static nanoindentation tests. Results showed that pristine bamboo fiber had poor nucleation ability for the crystallization of PP, while the fiber incorporated with nano-TiO2 could successfully form the TC in composites because of the effect of nano-TiO2 on inducing heterogeneous nucleation and the increase in fiber surface roughness which led to a higher nucleation ability. The interfacial stress transfer ability of composites was quantitatively evaluated by interfacial shear strength (IFSS). The results revealed that the IFSS of composites with interfacial TC increased by 48.9% compared with the composite without TC and the IFSS increased nonlinearly with the thickening of TC. Nanoindentation tests results demonstrated that the hardness (H) and modulus of elasticity (E) were increased by 53.46 and 24.65% in composite interphase due to the formation of TC. The correlation analysis indicated that better local mechanical properties of the interphase resulted in higher interfacial stress transfer ability in composites. [ABSTRACT FROM AUTHOR]

Keywords: bamboo; CO2 adsorption; mesopore; micropore; N2 adsorption EN bamboo CO2 adsorption mesopore micropore N2 adsorption 754 764 11 08/09/22 20220801 NES 220801 1 Introduction As one of the most important lignocellulosic resources, bamboo has received increasing attention due to its fast growth, high biomass yield, and superior mechanical properties, compared to wood ([5]; [30]). Figure 1 depicts the separation process of bamboo fibers and parenchyma cells, where a certain amount of 30-60 mesh bamboo powder was dispersed in water at a ratio of 1:20 and then stirred for 10-20 s, and the parenchyma cells floated atop the water while the bamboo fibers sank to the bottom due to their significant density difference. Graph: Figure 4: The N2 adsorption isotherm (a, c, e) and mesopore size distribution curve (b, d, f) of wood, bamboo, bamboo fibers and parenchyma cells of Moso bamboo. To study the differences in cell wall pore structure between bamboo fibers and parenchyma cells, a simple water separation method was used to physically separate bamboo fibers and parenchyma cells from Moso bamboo ( I Phyllostachys edulis i ). [Extracted from the article]

Parenchyma cells and fibers are the two dominant types of cells in the bamboo culm. Their mechanical and biological functions in bamboo differ substantially, derived from their cell wall structures and chemical compositions. The objective of this work was to comparatively study the hygroscopicity and the thermal degradation of bamboo fibers and parenchyma cells in order to better understand how to optimize heat treatment of bamboo. FTIR spectroscopy showed that parenchyma cells had a higher hemicellulose content and higher S/G lignin ratio than bamboo fibers based on the spectral changes at 1602 cm−1 with respect to 1505 cm−1. Upon heat treatment, spectral changes related to esterification reactions and loss of hydroxyl groups were observed. The heat treatment reduced hygroscopicity of parenchyma cells more than for bamboo fibers due to their lower thermal stability attributed to the higher hemicellulose content and less compact cell wall structure. Although heat treatment at 180 °C could improve the thermal stability of bamboo, mild heat treatments at 140 °C and 160 °C were found to be adequate to facilitate the degradation of bamboo. [ABSTRACT FROM AUTHOR]

Bamboo(Phyllostachys edulis) shoot was reported to be rich in phenolics. In the present study, free phenolics, conjugated phenolics, and insoluble‐bound phenolics of oven‐drying and freeze‐drying bamboo shoot tips were extracted and separated, of which total phenolic content (TPC), total flavonoid content (TFC), and their antioxidant activities were determined. Phenolics of different binding forms were qualitatively analyzed using HPLC–ESI–QqQ‐MS. A total of 22, 41, and 28 compounds were confirmed or tentatively identified in free, conjugated, and insoluble‐bound phenolic extraction, respectively. The majority of the identified compounds were organic acids and phenolic acids. Oven‐drying samples exhibited higher TPC (10.53–24.92 mg GAE/100 g DW) and TFC (5.80–33.27 mg CE/100 g DW) values, and stronger antioxidant activities (DPPH, ABTS, and FRAP) than freeze‐drying (TPC: 1.67–15.28 mg GAE/100 g DW, TFC: 1.43–29.05 mg CE/100 g DW). Insoluble‐bound phenolics were the major contributor to the total antioxidant activity. The present study investigated the phenolics composition and antioxidant activities of different binding forms in bamboo shoot tip comprehensively, and provided available information for their high‐value deep‐processing. [ABSTRACT FROM AUTHOR]

To obtain better interfacial bonding between bamboo fibers (BFs) and matrix polypropylene (PP), PP/BFs composites were prepared by means of modifying BFs with TiO2 nanoparticles. The static mechanical and dynamic mechanical properties, thermal properties, morphology and water resistance of the fabricated composites were characterized. The results showed the static and dynamic mechanical properties, thermal stability and water resistance of the composite were all improved at different extents by the introduction of TiO2 nanoparticles, especially with the addition of 0.4 wt% TiO2 nanoparticles (PP/BF/T3). The performances enhancement of TiO2 nanoparticles modified composites was mainly attributed to the interfacial bonding improvement, demonstrated by the Cole–Cole curves of dynamic mechanical analysis and the morphological analysis of fracture surface, as well as the increased crystallinity revealed with differential scanning calorimetry measurements. [ABSTRACT FROM AUTHOR]

Bamboo, with a high cellulose content comparable to that of wood, is a potential feedstock for biofuel and nanocellulose production. Mechanically isolated bamboo fibers and parenchyma cells exhibited remarkable differences in enzymatic hydrolysis efficiency as reported in a recent comparative study. It was assumed that cellulose microfibrils in bamboo fibers and parenchyma cells differ in their supramolecular structures. In the present study, X-ray diffraction and solid-state CP/MAS13C NMR studies indicated that, the two types of cells showed similar cellulose crystallinity index. The cellulose from bamboo fibers and parenchyma cells also exhibited differences in microfibril sizes, with lateral sizes of ca. 26.0–41.3 Å and ca. 22.7–39.3 Å for bamboo fibers and parenchyma cells respectively. It was further found that cellulose chains in bamboo fibers were more closely packed, supported by its smaller d-spacing than that of parenchyma cell cellulose. In addition, FT-IR and NMR spectroscopy revealed that there was a higher Iβ content in fibers than parenchyma cells. These differences in the crystalline structure of cellulose should be related to the lower recalcitrance to chemical degradation of parenchyma cells compared to bamboo fibers. These differences in the crystalline structure of cellulose should be related to the lower recalcitrance to chemical degradation of parenchyma cells compared to bamboo fibers. [ABSTRACT FROM AUTHOR]

Non‐isothermal crystallization kinetics of polypropylene/bamboo fiber/nano‐TiO2 (PP/BF/nano‐TiO2) composites was investigated using differential scanning calorimetric technique with various cooling rates (2.5, 5, 10, 20, and 30°C min−1). The influence of different loading concentration (0, 0.1, 0.4, and 0.8 wt%) of TiO2 nanoparticles on the nucleation ability of polypropylene was evaluated. The Avrami equation, Ozawa, and Mo model were applied to describe the non‐isothermal crystallization behaviors and to analyze the experimental data of the PP/BF/nano‐TiO2 composites. The Friedman isoconversional model was employed to calculate the effective activation energy (Ea) of the samples. The experimental data were in perfect agreement with the Mo model during the investigated crystallization temperature and the loading concentration of TiO2 nanoparticles. The TiO2 nanoparticles concentration of 0.4 wt% was useful for improving crystallization process of the PP matrix in the composites by accelerating the crystallization rate along with the lower values of t1/2 and Ea. However, we observed no significant changes in the onset crystallization temperature(To) and the crystallization peak temperature(Tp) with the incorporation of TiO2 nanoparticles in the PP matrix, suggesting that the influence of TiO2 nanoparticles was more remarkable at the crystal growth instead of nucleation stage for the PP/BF/nano‐TiO2 composites system. [ABSTRACT FROM AUTHOR]

It is frequently observed that bamboo particle composites (BPCs) do not show higher mechanical performances than the corresponding wood particles composites (WPCs), although bulk bamboo is much stronger than wood in mechanical performances. Herein this phenomenon was demonstrated from the cell compositions in the applied bamboo particles. To address that, a simple method to physically separate bamboo fibers (BFs) and bamboo parenchyma cells (BPs) from a bamboo particle mixture was developed. Polypropylene (PP) composites with pure BFs, BPs, a mixture of BFs and BPs (BFs + BPs), wood particles (WPs) as fillers were prepared. The flexural and dynamic mechanical properties, water absorption, and thermal properties were determined. The BF/PP composites showed the best mechanical performances (MOR at 35 MPa, MOE at 2.4 GPa), followed by WP/PP, (BF + BP)/PP, and BP/PP. They also exhibited the lowest water absorption and thickness swelling. Little difference was found for the thermal decomposition properties. However, a lower activation energy of BF/PP compared with BP/PP implied an uneven dispersion of BFs and weaker interfacial interaction between BF and PP. The results suggest that the mechanical performances and water resistance of bamboo particle/polymer composites can be significantly improved through cell separation. However, interface modification should be applied if higher performances of BF/PP composites are required. [ABSTRACT FROM AUTHOR]

It is well known the properties of resin impregnation wood is significantly influenced by the specific distribution pattern of resin in the modified wood. In this work, bamboo was furfurylated with an improved process. In addition to testing and evaluating its main physical, mechanical and durable properties, it was explored how the furfuryl alcohol (FA) resin is distributed in the furfurylated bamboo. To achieve this goal, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), nanoindentation, and imaging Fourier transform infrared microscopy (imaging FT-IR) were applied. SEM images demonstrates FA resin is mainly located in the parenchymal cell cavity of bamboo, however the existence of FA resin in the small cavities of the bamboo fibers is also observed by CLSM. In addition, the result of nanoindentation and imaging FT-IR both indicates that FA can penetrate and polymerize within the cell wall of the bamboo fiber. It is then concluded the heterogeneous but multi-scale distribution of FA resin should be responsible for the significant improvement of furfurylated bamboo in both dimensional stability and biological durability. [ABSTRACT FROM AUTHOR]

Studying the hygroscopic behavior of bamboo is important for industrial applications because it influences the dimensional stability and mechanical properties of the final bamboo products. In this study, the water vapor sorption behavior of 14 bamboo species was investigated using a dynamic vapor sorption apparatus and the results were analyzed using the Guggenheim-Anderson-de Boer (GAB) and Hailwood-Horrobin (H-H) models. The different bamboo species exhibited varying sorption isotherms and degrees of hysteresis. The reasons for this may be related to the different sorption isotherms of the two main cell units of bamboo, namely the fiber and parenchyma cells, and the chemical composition of bamboo. The GAB and H-H models provided good fits to the experimental data and meaningful physical parameters regarding the monolayer capacity, especially the water accessible specific surface area can be obtained from the GAB parameters. The fiber saturation point values were also determined using the GAB and H-H models, which ranged from 16.37 to 27.91% for the different bamboo species. [ABSTRACT FROM AUTHOR]

The aim of this study was to study the microstructure and mechanical properties of individual bamboo fibers after alkali treatment. The individual bamboo fibers were treated by sodium hydroxide (NaOH) solution with varying concentration (6, 8, 10, 15 and 25%) followed by rinsing and freeze-drying treatments. The alkali treated individual bamboo fibers were subsequently characterized by scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, confocal laser scanning microscopy and tensile strength tests. The results indicated that the alkali treatment resulted in more wrinkles and pores on the surface of bamboo fibers. Microfibril aggregates treated by 15 and 25% NaOH solution changed from a randomly interwoven structure to a granular structure. Cellulose I was transformed to cellulose II after 15 and 25% NaOH solution treatment. The alkali treatment reduced the diameter, lumen and cross sectional area of fiber, leading to the cracks in cell wall. The tensile strength and modulus of elasticity (MOE) of individual bamboo fibers decreased with alkali treatment. NaOH concentration almost did not affect the tensile strength but influenced the MOE significantly. The elongation at break of treated individual fiber increased significantly. When compared to untreated individual fibers, the elongation at break of the fiber was increased by 232 and 221% after 15 and 25% NaOH treatments, respectively. Besides, increasing alkali concentration caused the change of the fibers from brittleness to ductility, indicating that alkali treated bamboo fibers have a promising application in textile. [ABSTRACT FROM AUTHOR]

The mechanical properties of cell wall layers of bamboo fibers (BFs) and the interphase between BFs and maleated polypropylene polymer (MAPP) were investigated by means of peakforce quantitative nanomechanics based on atomic force microscopy. This technique is well suited for simultaneous imaging of several important material indicators, such as elastic modulus, deformation at peak force, and adhesion force between probe tip and sample. Furthermore, quantitative local mechanical information could be extracted from the obtained images by means of profile analysis. In case of BFs, the elastic modulus of the secondary cell wall and the compound middle lamella was found to be 21.3±2.9 GPa and 14.4±3.6 GPa, respectively, which agrees well with data measured by the nanoindentation technique. Additionally, this technique was also applied for bamboo plastic composites, and data from the transitional zone (interphase) between BFs and the MAPP matrix, with a thickness of 102±18 nm, could be obtained. [ABSTRACT FROM AUTHOR]

Color and physico-mechanical properties change from 10 months of natural outdoor weathering for injection molded bamboo flour (BF)/polypropylene (PP) foamed composites were investigated. The composite surface morphology, before and after exposure, was observed by using environmental scanning electron microscopy (ESEM). Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the chemical structures. Natural weathering was shown to cause more discoloration and surface deterioration, while the physico-mechanical properties, rheological behavior, and thermal stability were less negatively affected for composites with higher BF amount ranging from 0 to 35 wt%. The rheological behavior results indicated decreases in the storage and loss moduli and the complex viscosity of weathered composites. Crossover frequency was found to increase and the average molecular weight decreased. The initial thermal decomposition temperature declined in foamed PP by 25℃ and in 35% BF/PP foamed composite by 6℃, indicating a slight decline in thermal stability, as shown by thermogravimetric (TG) analysis. Photodegradation, photooxidation, and matrices chain scission in the composites were confirmed by FTIR and XPS analyses. [ABSTRACT FROM AUTHOR]

There is a growing need to characterize the mechanical properties of single bamboo fibers with their high potential in commercial applications. In this paper, an improved microtensile technique has been applied to measure the tensile strength of fibers isolated from Ma bamboo ( Dendrocalamus latiflorus Munro) as an important commercial bamboo species in China. The property variation with respect to the age and locations within a culm was in focus. Ma bamboo fibers had superior stiffness and strength data compared with those of softwood fibers. Four-year-old Ma bamboo fibers are stiffer and stronger than 1-year-old fibers. Their in-trunk variation is rather small both in radial and longitudinal directions. This is due to the relatively constant microfibrillar angle in bamboo culms. Accordingly, the large variations in the bulk mechanical properties of bamboo are mainly attributable to fiber distribution density in the culm rather than the fiber itself. [ABSTRACT FROM AUTHOR]

In order to reduce the density and improve the toughness of wood-plastic composite (PC), the foamed PC was made through adding chemical foaming agent in this study. To fully utilize bamboo resources in China and reduce white pollution, the foamed composite with 54% PPM and 13% HMSPP containing 33% bamboo powder and 1% modified azodicarbonamide (AC) foaming agent blends by weight was made by injection molding. Furthermore, the aging performance of bamboo powder/polypropylene (PP) foamed composites was studied in order to investigate the weathering mechanism of WPC and to strengthen its production and quality management and thus expand its application fields. The composites were exposed to 1 200 h accelerated xenon-arc radiation with water spray, the mechanical characteristics including bending performance, notched impact strength, and color change of composites were studied. The rheological behavior of composites with regard to frequency sweep ranges from 0.01 to 70 Hz at 195? was observed. The surface morphology of composites with non-weathered and weathered for 1 200 h were investigated by ESEM and their chemical structures were analyzed by FTIR. The results showed that the mechanical properties of composites decreased significantly for weathering 300 h and decreased continuously with an increase of exposure time. The retentions of residual bending strength, flexural modulus and notched impact strengths were only 79.4%, 68.3% and 75.6% respectively. The weathering also resulted in significant color fading of the composites, especially for the first 900 h. The color began to change slowly within the next 300 h. After weathering for 1 200 h, the color change ΔE*, lightness change ΔL*, redness change Δa* and yellowness change Δb* were 49.0, 48.4, -5.9 and -4.9 respectively. The frequency sweep results indicated that the storage modulus, loss modulus and complex viscosity of composite weathered for 1 200 h decreased and the intersection value of energy storage modulus and loss modulus become lower, and the corresponding frequency was higher. These results indicated that the molecular weight distribution become wider and the molecular weight became lower. The ESEM observation revealed that the surface of weathered composite was no longer smooth; and the cracks and holes appeared and some bamboo fibers exposed. The FTIR analysis showed the new peak of C=O stretching vibration at 1 717 cm-1 appeared and C=C absorption peak at 1 459 cm-1 strengthened and C=O stretching vibration peak at 1 059 cm-1 also strengthened. The FTIR result verified the photooxidation and photodegradation of composites for accelerated weathering. [ABSTRACT FROM AUTHOR]

Bamboo fibers are very promising reinforcements for polymer composites production due to its high aspect ratio and strong mechanical performances. In order to better understand their reinforcing potential, the mechanical properties of single bamboo fibers extracted from eleven commercial bamboo species in China were measured with a newly developed microtensile technique. For comparison, the mechanical properties of mature single Chinese Fir and Masson Pine wood fibers were measured. The results show that the average longitudinal tensile modulus of the eleven kinds of bamboo fibers ranges from 25.5 to 46.3 GPa with an average value of 36.7 GPa. For tensile strength, the value ranges from 1.20 to 1.93 GPa with an average value of 1.55 GPa. The tensile strength and modulus of bamboo fibers are nearly two times of that of single Chinese Fir and Masson Pine fibers, and significantly higher than most of the published data for other softwood fibers. The average elongation at break of bamboo fibers is about 4.84 %, only a little lower than the value 5.15 % of the tested mature softwood fibers. Additionally, bamboo fibers were found to have smaller diameters and larger aspect ratio than most documented wood fibers, which favored an improved reinforcing effect. These combined mechanical and morphological advantages highlight the potential of bamboo fibers as the reinforcing phase in polymer composites for structural purpose. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, bamboo fiber/high-density polyethylene (HDPE) composites were prepared, and the effects of nano-TiO2 on their thermal properties and crystallization behavior were investigated via thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results show that the addition of nano-TiO2 improved the thermal stability and had a dual function in the crystallization behavior of the composites. On one hand, it functioned as a nucleating agent. The addition of 2 wt % nano-TiO2 promoted the crystallization, which caused the increase of the crystallization rate and crystallinity degree, as well as the micronization of the crystalline grain. On the other hand, intermolecular hydrogen bonds and covalent bonds were formed between nano-TiO2 and the polymer matrix, which hindered the crystallization of the composites. When the content of nano-TiO2 was continually increased, the inhibitory effect of the crystallization was gradually enhanced, which resulted in a decrease in the crystallization rate and crystallinity degree of the composites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39846. [ABSTRACT FROM AUTHOR]

Bamboo is much more easily attacked by fungus compared with wood, resulting in shorter service life and higher loss in storage and transportation. It has been long accepted that the high content of starch and sugars in bamboo is mainly responsible for its low mould resistance. In this paper, acetic acid, propionic acid, oxalic acid, citric acid, and hydrochloric acid were adopted to hydrothermally hydrolyze the starch in bamboo, with the aims to investigate their respective effect on the mould and blue-stain resistance of bamboo, and the optimized citric acid in different concentrations were studied. The starch content, glucose yields, weight loss, and colour changes of solid bamboo caused by the different acidic hydrolysis were also compared. The results indicated that weak acidic hydrolysis treatment was capable of improving mould-resistant of bamboo. The mould resistance increased with the increased concentration of citric acid. Bamboo treated with citric acid in the concentration of 10% could reduce the infected area ranging to 10–17%, the growth rating of which could reach 1 resistance. The content of soluble sugar and starch remained in bamboo decreased significantly from 43 mg/g to 31 mg/g and 46 mg/g to 23 mg/g, respectively, when the citric acid concentration varied from 4% to 10%. Citric acid treatments of 10% also caused a greatest surface colour change and weight loss. The results in this study demonstrated citric acid treatment can effectively reduce the starch grain and soluble sugars content and improve mould resistance of bamboo, which can be attributed to the reduction of starch grain and soluble carbohydrates (such as glucose, fructose, and sucrose, etc.) in bamboo. [ABSTRACT FROM AUTHOR]

Nitrogen (N) losses from agricultural fields have been extensively studied. In contrast, surface runoff and N losses have rarely been considered for bamboo forests that are widespread in regions such as southern China. The thriving of bamboo industries has led to increasing fertilizer use in bamboo forests. In this study, we evaluated surface runoff and N losses in runoff following different fertilization treatments under field conditions in a bamboo ( Phyllostachys pubescens) forest in the catchment of Lake Taihu in Jiangsu, China. Under three different fertilization regimes, i.e., control, site-specific nutrient management (SSNM), and farmer's fertilization practice (FFP), the water runoff rate amounted to 356, 361, and 342 m ha and accounted for 1.91, 1.98, and 1.85 % of the water input, respectively, from June 2009 to May 2010. The total N losses via surface runoff ranged from 1.2 to 1.8 kg ha. Compared with FFP, the SSNM treatment reduced total nitrogen (TN) and dissolved nitrogen (DN) losses by 31 and 34 %, respectively. The results also showed that variations in N losses depended mainly on runoff fluxes, not N concentrations. Runoff samples collected from all treatments throughout the year showed TN concentrations greater than 0.35 mg L, with the mean TN concentration in the runoff from the FFP treatment reaching 8.97 mg L. The loss of NO-N was greater than the loss of NH-N. The total loss of dissolved organic nitrogen (DON) reached 23-41 % of the corresponding DN. Therefore, DON is likely the main N species in runoff from bamboo forests and should be emphasized in the assessment and management of N losses in bamboo forest. [ABSTRACT FROM AUTHOR]

Imparting excellent preservative performances to bamboo is the key to expand the applications of this extraordinary non-wood forest resource. This study reports on the formation of ZnO-nanostructured network films on the surface of bamboo via a simple two-step process. This process consists of the generation of ZnO seeds on the bamboo surface followed by a solution treatment to promote the crystal growth. The morphology and chemical composition of the ZnO films were studied by field-emission scanning electron microscopy combined with energy-dispersive X-ray analysis and X-ray diffraction. Accelerated weathering was used to evaluate the photostability of the treated wood. The antifungal and antibacterial performances were also examined. The results indicate that the approach can simultaneously furnish bamboo with excellent photostability and antifungal and antibacterial performances. The growth mechanism of ZnO-nanostructured network films on the uneven and chemically complicated surface of bamboo was also discussed. [ABSTRACT FROM AUTHOR]

More mechanical information on fibers is needed for better understanding of the complex mechanical behavior of bamboo as well as optimizing design of bamboo fiber based composites. In this paper, in situ imaging nanoindentation and an improved microtensile technique were jointly used to characterize the longitudinal mechanical behavior of fibers of Moso bamboo ( Phyllostachys pubescens Mazei ex H. de Lebaie) aged between 0.5 and 4 years. These methods show that 0.5-year-old fibers have similar mechanical performances to their older counterparts. The average longitudinal tensile modulus and tensile strength of Moso bamboo fibers ranges from 32 to 34.6 GPa and 1.43 to 1.69 GPa, respectively, significantly higher than nearly all the published data for wood fibers. This finding could be attributed to the microstructural characteristics of the small microfibrillar angle and scarcity of pits in bamboo fibers. Furthermore, our results directly support the assumption that the widely used Oliver-Pharr analysis method in nanoindentation test significantly underestimates the longitudinal elastic modulus of anisotropic plant cell wall. [ABSTRACT FROM AUTHOR]

In this study, bamboo was treated with an optimized surface furfurylation process. With this process, dimensionally stable and highly biologically durable bamboo material could be prepared without mechanical reduction. The anti-swelling efficiency (ASE) could reach 50% with a low weight percent gain (WPG about 13%). By using SEM, nanoindentation, and Imaging FTIR, we demonstrated that this high performance improvement is attributed to the unique furfuryl alcohol (FA) resin distribution pattern in the modified bamboo, namely a higher concentration of FA resin located in the region near to the surface of bamboo, and what is more, the preferred distribution of FA resin within the cell walls of parenchyma cells, which is known to be the weak point of bamboo both for biological durability and mechanical performances. Such graded modified bamboo could be utilized as a reliable engineering material for outdoor applications. [ABSTRACT FROM AUTHOR]

Bamboo engineering materials are made from abundant raw material sources and can be easily prepared with minimal processing and low pollution. However, when used as structural materials, they are limited by their weight, strength, and lack of stable designability. The use of laminated structure and a gluing interface are key factors affecting the performance of bamboo engineering materials. Bamboo exhibits excellent toughness and strength when resisting external forces, with a multi-level interlocking reinforced interface with bamboo's intercellular layer that induces an increase in crack deflection paths (internal toughening) and cell wall energy consumption (external toughening) coupled to microfibril pulling out. Inspired by the functionally graded structure of the lightweight and high-strength bamboo wall layer and the interlocking reinforced interface between vascular bundles and parenchyma cells, we designed a high-performance bamboo engineering material designed to imitate bamboo, Imitation Bamboo Bundle Laminated Veneer Lumber (IBLVL), prepared by uniform lamination and gradient molding. The designed IBLVL is light in weight, with high strength and uniform density. This work demonstrates the feasibility of using resource-rich and sustainable bamboo to manufacture light-weight bamboo engineering materials with high strength and high toughness that can be substituted for non-renewable resources in the fields of construction and transportation. • Explains the mechanism of the excellent properties of bamboo itself. • IBLVL is designed to imitate bamboo features. • IBLVL has excellent strength, toughness and dimensional stability. • The mechanism of the excellent performance of IBLVL revealed. [ABSTRACT FROM AUTHOR]

Bamboo holds great promise as a versatile material in construction and engineering. However, its inherent hydrophilic nature, particularly within its cell walls, presents challenges for dimensional stability, limiting its widespread use. Addressing this challenge, vapor phase furfurylation (VPF) has emerged as a promising technique for bamboo modification. In this study, we applied VPF to bamboo for the first time, resulting in a significant transition towards hydrophobicity and a remarkable enhancement in dimensional stability (ASE > 50 %). Employing a multifaceted approach, we investigated the distribution gradient and penetration depth of FA resin within furfurylated bamboo using advanced methodologies such as scanning electron microscopy (SEM), nanoindentation, dynamic vapor sorption (DVS), and imaging FT-IR microscopy, demonstrating the improvement in dimensional stability is attributed to cell wall bulking from FA resin infiltration. Through meticulous parameter refinement, we identified an optimized protocol comprising 40 h of VPF exposure, a VPF temperature of 115 °C, and a 4.5 % concentration of maleic anhydride (MA). This tailored VPF methodology holds promise for enhancing the dimensional stability of bamboo while minimizing FA consumption, thus expanding its potential applications in construction and furniture industries. • A high-stable bamboo was prepared by a novel VPF modification with low-resin load. • FA resin penetrates into bamboo with a graded distribution after VPF modification. • The VPF process reduces FA usage and energy compare with traditional furfurylation. [ABSTRACT FROM AUTHOR]

Understanding the distribution and accessibility of polymers within plant cell walls is crucial for addressing biomass recalcitrance in lignocellulosic materials. In this work, Imaging Fourier Transform Infrared (FTIR) and Raman spectroscopy, coupled with targeted chemical treatments, were employed to investigate cell wall polymer distribution in two bamboo species at both tissue and cell wall levels. Tissue-level Imaging FTIR revealed significant disparities in the distribution and chemical activity of cell wall polymers between the fibrous sheath and fibrous strand. At the cell wall level, Imaging Raman spectroscopy delineated a distinct difference between the secondary wall and intercellular layer, with the latter containing higher levels of lignin, hydroxycinnamic acid (HCA), and xylan, and lower cellulose. Mild acidified sodium chlorite treatment led to partial removal of lignin, HCA, and xylan from the intercellular layer, albeit to a lesser extent than alkaline treatment, indicating susceptibility of these polymers to chemical treatment. In contrast, lignin in the secondary wall exhibited limited reactivity to acidified sodium chlorite but was slightly removed by alkaline treatment, suggesting stable chemical properties with slight alkaline intolerance. These findings provide valuable insights into the inherent design mechanism of plant cells and their efficient utilization. In this work, the application of Imaging FTIR and Raman spectroscopy, in conjunction with chemical treatments, provided valuable insights into the distribution and accessibility of polymers in bamboo from two distinct species at both tissue and cell wall levels. Specifically, alkaline treatment demonstrated higher sensitivity towards lignin and HCA, particularly within the intercellular layer, suggesting a preferential removal of ester bonds. Conversely, acidified sodium chlorite treatment primarily targeted lignin within the secondary wall, indicating differential reactivity based on the chemical composition and structure of the target polymers. This insight not only enhances our understanding of bamboo's chemical properties but also informs the selection of appropriate processing methods for biorefinery applications. The visualization of chemical treatment on cell wall has reference significance for multiple chemical engineering technologies. [Display omitted] [ABSTRACT FROM AUTHOR]

Biomass recalcitrance, a key challenge in biomass utilization, is closely linked to the architectural composition and cross-linkages of molecules within cell walls. With three bamboo species investigated, this study aims to elucidate the inherent molecular-scale structural differences between bamboo fibers and parenchyma cells through a systematic chemical extraction and structural characterization of isolated hemicelluloses, lignin, and lignin-carbohydrate complexes (LCC). We observed that parenchyma cells exhibit superior alkaline extractability compared to fibers. Additionally, we identified the hemicelluloses in parenchyma cells as L-arabino-4- O -methyl-D-glucurono-D-xylan, displaying a highly branched structure, while that in fibers is L-arabino-D-xylan. Furthermore, the parenchyma cell lignin exhibited a higher syringyl-to-guaiacyl (S/G) ratio and β- O -4 linkage content compared to fibers, whereas fibers contain more carbon‑carbon linkages including β-β, β-5, and β-1. This notable structural difference suggests a denser and more stable lignin in bamboo fibers. Importantly, we found that LCC in parenchyma cells predominantly comprises γ-ester linkages, which exhibit an alkaline-unstable nature. In contrast, fibers predominantly contain phenyl glycoside linkages, characterized by their alkaline-stable nature. These findings were observed for all the tested bamboo species, indicating the conclusions should be also valid for other bamboo species, suggesting the competitiveness of bamboo parenchyma cells as a valuable biofuel feedstock. Note: In this work, based on analysis on bamboo lignin, hemicelluloses and LCC, the cell wall deduction pattern of bamboo fibers, characterized by alkaline-stable nature, and parenchyma cells, featured as alkaline-stable nature, was firstly established. The study presented here lays a foundation for future research aimed at optimizing the utilization of bamboo parenchyma cells for sustainable biorefinery applications. [Display omitted] • Bamboo parenchyma cells exhibit superior alkaline extractability than bamboo fibers. • Differences in fibers and parenchyma were found on lignin, hemicelluloses and LCC. • Bamboo parenchyma cells are a valuable biofuel feedstock for bioethanol production. [ABSTRACT FROM AUTHOR]

Developing high-performance plant fiber-reinforced thermoplastic polymer composites using environmentally friendly and cost-effective methods remains a significant challenge. In this study, we present a novel micro-nano strategy for producing robust short bamboo fibers (BFs) reinforced polypropylene (PP) composites (SBFPCs) without the need for chemical modification. Our approach involves the utilization of purified short micron BFs, which is surface-coated with holocellulose nanofibers (HNFs) extracted from bamboo parenchyma cells (BP). Through conventional injection processing, the resulting SBFPCs demonstrate remarkable mechanical enhancements with just a 0.2 wt% addition of HNFs compared to control samples. Notably, the mechanical properties of our SBFPCs surpass those of most reported short plant fiber-reinforced thermoplastic composites. The superior mechanical performance of our SBFPCs can be attributed to several factors, including the use of purified micron BFs with optimal aspect ratios as the primary reinforcement phase, enhanced interfacial mechanical interlocking between BFs and the PP matrix facilitated by the addition of HNFs, and the potential dispersion of HNFs within the PP matrix at submicron or nanoscale as a secondary reinforcement phase. This study highlights the promising application of SBFPCs in engineering areas with stringent mechanical requirements. [ABSTRACT FROM AUTHOR]

Lignin is widely recognized as a key factor influencing the recalcitrance of lignocellulosic biomass, yet the specifics of this relationship remain complex and not fully understood due to the complex interplay between lignin content variation and cell wall structure. Bamboo, which exhibits greater recalcitrance compared to wood in biorefinery processing, was chosen as the focus of investigation in this study. Three variants of Dendrocalamus farinosus with high, middle and low lignin contents were systematically analyzed and compared, in terms of molecular structure of lignin, hemicelluloses and cellulose, cell wall polymer spatial orientation, lignin-carbohydrate complex (LCC) linkages, cell wall geometrical size, as well as deconstruction efficiency, including delignification, alkaline extraction, and cellulose enzymatic hydrolysis efficiency. Findings reveal that an increase in lignin content generally lowers bamboo's deconstruction efficiency, but the mechanisms are more nuanced than previously thought. While lignin content variations do not significantly affect the molecular structure of xylan, cellulose and the chemical linkage type of LCC linkages, they do impact cellulose crystallinity, xylan orientation and notably, the thickness of fiber cell wall in the free fiber stands of bamboo. These findings highlight that lignin's role extends beyond mere physical protection of the cell wall, but also induces subtle variations in polymer structure and cell wall morphologies, which collectively influence the deconstruction efficiency of bamboo cell walls. [ABSTRACT FROM AUTHOR]

• The detection model realizes identifying, positioning, and counting intelligently. • The number of vascular bundles in bamboo grown in different areas is 7196 ± 698. • The differences result from the culm dimension and the growing environment. • From the base to top, the number of vascular bundles decreased from 8000 to 300. • Vascular bundles in node decrease mainly due to the Type 2 & 3 vascular bundles. The vascular bundle is the most important structural unit of bamboo that determines the growth of bamboo and the properties of bamboo-based materials. A systematic understanding of the characteristics of vascular bundle is the key to clarify the structure-property relationship of bamboo. In this paper, the YOLO (You Only Look Once) algorithm was applied to the field of bamboo structure and a detection model was proposed to solve the key technical problems regarding automatic detection, positioning, counting, and automatic measurement of relevant parameters of vascular bundles. The precision of the detection model was up to 99.59 %, and able to achieve the work in minutes that cannot be done manually. Furthermore, we studied the variation of inter-plant and the variation of axial direction of Moso bamboo [ Phyllostachys edulis (Carr)H. de Lebaie]. The results indicated that the total number of vascular bundles of Moso bamboo from 12 different areas was 7196 ± 698, the distribution density of vascular bundles was 2.49 ± 0.58 per mm2, the fiber volume fraction was 23.68 ± 1.89 %. The apparent differences of vascular bundles in different areas result from the growing environment. There were approximately 8000 vascular bundles in the base of Moso bamboo while the number decreased to around 300 at the top, and the decreased vascular bundles were mainly semi-open type and open type. The total area of fiber sheath decreased linearly from base to top of internodes, while the fiber volume fraction was 20–30 % constantly. [ABSTRACT FROM AUTHOR]

Highlights • Hydrophobic and compressible CNF aerogel are prepared by a facile synthesis method combing aqueous silylation and freeze-casting. • The hydrophilicity and fragility of CNF aerogel were simultaneous addressed without requiring any post-treatments. • Freeze-casted silylated aerogel exhibited direction-dependent structure and compression properties. Abstract Cellulose aerogels have shown outstanding potential as renewable functional materials; however, their practical applications are still limited by inherent hydrophilicity and weak mechanical properties. To overcome hydrophilicity and fragility issues of aerogels, in this study, silylated bamboo-derived cellulose nanofibrils (CNF) aerogels with aligned porous structures were achieved by directionally freeze-casting a mixture of CNF suspension and methyltrimethoxysilane sol. The silylated CNF aerogels exhibited distinct aligned lamellar structures and significantly anisotropic mechanical properties. They had improved strength and stiffness in the axial direction (along the freezing direction) and excellent rapid shape recovery ability in the radial direction (perpendicular to the freezing direction) with a significant high shape recovery ratio of 92% after 100 cycles at 80% compression. Owing to their ultra-low density, hydrophobicity, and high compressive recoverability, the silylated CNF aerogels can be potentially used in a wide range of industrial applications, such as hydrophobic polymer nanocomposites, absorbents, and biomedical scaffolds. [ABSTRACT FROM AUTHOR]

The pore structure of the cell wall is closely related to biomass recalcitrance. Bamboo fibers and parenchyma cells constitute the main body of bamboo but have significantly different chemical decomposition efficiencies. This study compared the influence of chemical removal on the porosity, pore size distribution, and hygroscopicity of fibers and parenchyma cells in bamboo. The results exhibited that parenchyma cells were more porous and hygroscopic as compared to fibers. However, both cell types exhibited similar changes during sequential chemical removal. The removal of extractives produced many more micropores than mesopores in the cell walls, which were mainly concentrated in the size ranges of 0.4–1.0 nm and 2–10 nm. Delignification reduced both the cell wall porosity and micropore volume, which was attributed to the easy collapse of delignified cell walls in powder samples, as well as the disappearance of micropores in lignin. Several mesopores with a diameter of 2–10 nm were created upon removing hemicellulose after delignification, but almost all micropores disappeared. Changes in the porosity and chemical compositions synergistically affected the water sorption and hysteresis of bamboo. The delignified samples contained more exposed sorption sites, which displayed stronger dynamic water vapor sorption. After removing hemicellulose, the sample exhibited lower water sorption, primarily due to a reduction in the number of sorption sites. The absorption hysteresis of bamboo decreased upon decreasing the cell wall porosity. • Cell wall pore structures are related to chemical removal and specific cell types in bamboo. • Removal of lignin and hemicellulose reduced cell wall porosity of bamboo. • There is a good correlation between moisture sorption hysteresis with cell wall porosity. [ABSTRACT FROM AUTHOR]

Mainly composed of fibers and parenchymal cells with strikingly different chemical compositions and cell wall structures, bamboo represents an important alternative resource for bio-refinery. Therefore, this study proposes a potentially novel, low-energy consumption approach for producing high-quality nanocellulose fibrils (NCFs) made from bamboo at large scale. For this purpose, bamboo pulping sheets (mainly composed of fibers) and bamboo processing residues (mainly composed of parenchymal cells) were chosen as starting materials from which NCFs were isolated with a simple high-pressure homogenization process. Wet chemical analysis, Scanning Electron Microscope (SEM), and microtensile tests were applied to investigate the effects different cell types had on the properties of prepared NCFs, as well as the amount of energy required to produce them. The results show that the energy required for isolating NCFs from parenchymal cells was significantly lower than that from bamboo fibers, while the quality of NCFs produced from the two types of cells were similar. In addition to the relative ease of the procedure and the low-energy required, as bamboo processing residues produced in a number of industrial bamboo applications normally contain a high ratio of parenchymal cells and can be obtained at relatively low costs, this represents a very promising source of raw material for the production of NCFs. [ABSTRACT FROM AUTHOR]

Bamboo fibers are known for their outstanding mechanical properties and could be a potential replacement for synthetic fibers used in fiber-reinforced composites. In this paper, mechanical variation related to age for elementary fibers of two important sympodial bamboo species ( Dendrocalamopsis oldhami and Dendrocalamus latiflorus Munro) was analyzed using a microtension technique. From the investigation of elementary fibers ranging from 1 to 6 years in age, our results showed the average tensile modulus of the two types of bamboo fibers ranged from 42.84 GPa to 44.29 GPa and 33.51 GPa to 37.35 GPa, whereas the tensile strength ranged from 1.50 GPa to 1.70 GPa and 1.34 GPa to 1.52 GPa, respectively. These values are significantly higher than equivalent properties found in most natural plant fibers. Furthermore, bamboo fibers were found to have nearly reached their optimal mechanical properties after just 1 year, with subsequent variations in older fibers proving statistically insignificant. This highlights the suitability of using young bamboo fibers as the reinforcing phase in polymer composites. [ABSTRACT FROM AUTHOR]

The mechanical performance and dimensional stability of bamboo is highly dependent on the microfibril orientation in its cell wall sublayers. However, a comprehensive and quantitative description of this orientation at the sublayer scale of cell wall is very challenging to do. Here, we proposed a new approach to quantitatively estimate the cellulose microfibril orientation across the whole cell wall of both fibers and parenchyma cells in bamboo. This new approach is based on the geometrical correlation between the actual and apparent dimensions of cellulose microfibril aggregates, which are respectively determinedly with CP/MAS 13C NMR and high-resolution field emission scanning electron microscopy (FE-SEM). For comparison, the average microfibril angle (MFA) of both fibers and parenchyma cells were also measured using X-ray diffraction (XRD). It was concluded that the cellulose microfibrils in the broad sublayers of the bamboo fibers exhibited a relatively small MFA of about 10°, while those in the narrow sublayers were nearly oriented in the transverse with a MFA of about 80°. For parenchyma cells, the MFA of the broad and narrow sublayers were estimated to be 50–70° and 70–80°, respectively. Modified cell wall structural models for the two types of cells were then proposed. • Microfibril orientation of bamboo at cell wall sub-layers were estimated using a new method. • Microfibril angle in narrow sublayers of bamboo fibers is about 80º. • The broad sublayers of bamboo fibers has a small microfibril angle of about 10º. • Microfibril angle of parenchyma cells is much larger than that of fibers. [ABSTRACT FROM AUTHOR]

Biomass recalcitrance is believed to be related to the hierarchical and heterogeneous structures of plant cell walls. In this study, the alkaline extraction efficiency of bamboo fibers and parenchyma cells is found to be highly related to their structural differences on both anatomical and molecular level. Advanced NMR spectroscopy demonstrated the lignin and hemicelluloses (mainly xylan) from fibers and parenchyma cells are significantly different in their molecular structure. The parenchyma lignin contains more β- O -4 linkages with much higher syringyl/guaicyl (S/G) ratio. By contrast, the fiber lignin contains more stable β-β and β-5 linkages as compared to parenchyma lignin. Although the hemicelluloses from both bamboo fibers and parenchyma cells shows similar molecular structure of L -arabino-4- O -methyl- D -glucurono- D -xylan, the latter contains more 4- O -methyl-α- D -glucuronic acid units. These structural discrepancies can provide explanations why the parenchyma cells have much higher "alkaline extraction efficiency" than fibers, further indicating the former is a promising feedstock in the current biorefinery scenario. Bamboo dominantly consists of stiff sclerenchyma fibers (account for 40% by volume) and soft matrix parenchyma cells (account for 52% by volume). Solution-state 2D heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) demonstrated that bamboo parenchyma cells lignin has a higher S/G ratio and more β- O -4 substructures, but lower content of β-β and β-5 linkages, which contribute to a relatively high reactivity under alkaline treatment. Bamboo parenchyma cells, with both the unconsolidated cell structure and the instable macromolecule structure, could be regarded as a highly competitive "easy bio-conversion" materials. [Display omitted] • Bamboo fibers and parenchyma cells exhibits distinct differences at both anatomical and molecular levels. • Parenchyma cells are easier to be extracted by alkali than fibers. • Lignin in parenchyma cells contained more β- O -4 linkage with higher S/G ratio. • Bamboo parenchyma cells are ideal easily-converted feedstock. [ABSTRACT FROM AUTHOR]

Abstract: Rice straw pellets are the main type of biomass solid fuel and have great potential as a bioenergy resource of the future in China. But it also showed important problems because of its high content of ashes and its low gross calorific value, reducing the possibility to be used in domestic heating. It was certified that mixing different types of biomass materials was helpful to improve the properties of pellets. To improve properties of rice straw pellets and investigate the effect of mixing bamboo and rice straw on the pellet properties, some properties of pellets, manufactured using different mixing ratio of bamboo and rice straw particles, were determined in this research. It can be concluded from this research that physical properties of all pellets meet the requirements of Pellet Fuels Institute Standard Specification for Residential/Commercial Densified except for bulk density of pellets, manufactured using mixing ratio (≤3:2) of bamboo and rice straw. The inorganic ash and gross calorific value of rice straw pellets cannot meet the requirement of Pellet Fuels Institute Standard Specification for Residential/Commercial Densified (8.0%) and the minimum requirement for making commercial pellets of DIN 51731 (>17,500 J/g). Both properties are improved through mixing bamboo particles and rice straw particles. It is significant that inorganic ash content and gross calorific value of pellets, manufactured using mixing ratio (≥3:2) of bamboo and rice straw, were lower than 8.0% and higher than 17,500 J/g, respectively. This also shows that mixing different biomass materials is an effective way to optimize properties of biomass solid fuel. All pellets after improvement are proposed as biomass solid fuel and have the potential to be developed as commercial pellets on an industrial scale in China. [Copyright &y& Elsevier]

To better understand the high recalcitrance of bamboo during bioconversion, the fine spatial distribution of polymers in bamboo was studied with Imaging FTIR microscopy under both transmission and ATR modes, combined with PCA data processing. The results demonstrated that lignin, xylan and hydroxycinnamic acid (HCA) were more concentrated in the fibers near the xylem conduit, while cellulose was evenly distributed across the whole fiber sheath. PCA processing produced a clear separation between bamboo fibers and parenchyma cells, indicating that the parenchyma cells contains more pectin and HCA than fibers. It also demonstrated that cellulose, xylan and S-lignin were concentrated most heavily in bamboo fiber secondary cell walls, while G-lignin, pectin and HCA were found more in the compound middle lamella. The revealed information regarding polymer distribution is of great significance for better understanding of the inherent design mechanism of plant cell wall and its efficient utilization. Imaging FTIR with ATR first demonstrated that for bamboo, in similarity with wood species, the spatial distribution of cellulose, xylan and S-lignin were concentrated most heavily in the fiber secondary cell walls, while G-lignin, pectin and hydroxycinnamic acid (HCA) were found more in the compound middle lamella. At the tissue level, imaging FTIR with transmission mode first demonstrated that lignin, xylan and HCA were more concentrated in the fibers near xylem conduit, while cellulose was evenly distributed across the whole fiber sheath. [Display omitted] • The polymers distribution in bamboo at both tissue and cellular scale was revealed with Imaging FITR • Xylan and lignin were found to be more concentrated in the fibers near the xylem conduit in bamboo • Cellulose, xylan and S-lignin were more concentrated in the secondary wall [ABSTRACT FROM AUTHOR]

• A surface furfurylation was studied to improve the dimensional stability and durability of bamboo. • The dimensional stability and durability of bamboo have significant increase with a low WPG. • The mechanical properties did not decrease after surface furfurylation. • A starting processing parameters was proposed for the simple surface furfurylation. Furfurylation has long been adopted for wood modification, and found to be effective for bamboo as well. However, traditional full impregnation furfurylation would reduce the dimensional stability of bamboo although its biological durability was improved. Here, we found surface modification with furfuryl alcohol (surface furfurylation) was particularly suitable for bamboo, which is extremely hard to be treated due to its low transverse mass transportation. To optimize the surface furfurylation process for bamboo, an orthogonal experiment was designed with several key physical and mechanical properties tested, including weight percent gain (WPG), equilibrium moisture content (EMC), anti-swelling efficiency (ASE), modulus of rupture (MOR), modulus of elasticity (MOE). Using this process, dimensionally stable (ASE could reach as high as 50% by volume) and highly biological durable (strong resistance against mould, decay and termite) bamboo material with low consumption of furfuryl alcohol (FA) (average WPG lower than 15%) were prepared avoiding significant reduction in mechanical properties. Furthermore, a parameter combination of 70% FA concentration, 105 ℃ curing temperature, and 5 h curing time was proposed as an optimized process for pilot-scale production based on orthogonal experiments and range analysis. [ABSTRACT FROM AUTHOR]

• Furfurylation was demonstrated for the first time to be highly efficient for bamboo modification due to the high permeability of furfural alcohol (FA). • The modified bamboo was found to be highly resistant to mold, decay fungi and termites with low FA weight percentage gain (WPG). • The mechanical properties of furfurylated bamboo could be moderately enhanced at low FA concentrations. Bamboo is an important sustainable material for construction industry due to its combined advantages of easy availability, fast renewability, and excellent mechanical performance. However, its low biological durability and poor treatability limit its use for structural and outdoor building material. In this study, highly durable bamboo materials were prepared through a facile modification process called bulk furfurylation for the first time. The modified bamboo was found to be highly mold resistant and exhibited strong resistance to decay fungi and termites with a furfuryl alcohol (FA) weight percentage gain (WPG) as low as 10%. A strong positive correlation was detected between WPG and termite resistance, but not for mold or decay resistance. The mechanical properties of the furfurylated bamboo were moderately enhanced at low FA concentrations and were much less affected by curing temperature and time. Based on these results, it is concluded the furfurylated bamboo would have wide application in construction. [ABSTRACT FROM AUTHOR]