Synergistic preparation of a straw fiber/polylactic acid composite with high toughness and strength through interfacial compatibility enhancement and elastomer toughening.

Plant fiber-reinforced polylactic acid (PLA) composites are extensively utilized in eco-friendly packaging, sports equipment, and various other applications due to their environmental benefits and cost-effectiveness. However, PLA suffers from brittleness and poor toughness, which restricts its use in scenarios demanding high toughness. To expand the application range of plant fiber-reinforced PLA-based composites and enhance their poor toughness, this study employed a two-step process involving wheat straw fiber (WF) to improve the interfacial compatibility between WF and PLA. Additionally, four elastomeric materials-poly (butylene adipate-co-terephthalate) (PBAT), poly (butylene succinate) (PBS), polycaprolactone (PCL), and polyhydroxyalkanoate (PHA)-were incorporated to achieve a mutual reactive interface enhancement and elastomeric toughening. The results demonstrated that Fe3+/TsWF/PLA/PBS exhibited a tensile strength, elongation at break, and impact strength of 34.01 MPa, 14.23 %, and 16.2 kJ/m2, respectively. These values represented a 2.4 %, 86.7 %, and 119 % increase compared to the unmodified composites. Scanning electron microscopy analysis revealed no fiber exposure in the cross-section, indicating excellent interfacial compatibility. Furthermore, X-ray diffraction and differential scanning calorimetry tests confirmed improvements in the crystalline properties of the composites. This work introduces a novel approach for preparing fiber-reinforced PLA-based composites with exceptional toughness and strength.

Effect of Fiber Loading on Mechanical and Flame-Retardant Properties of Poplar-Fiber-Reinforced Gypsum Composites.

Gypsum-based composites were prepared via a slurry casting process using construction gypsum as the binding material and poplar fibers as reinforcing material. The effects of different fiber content and curing time on the mechanical properties, water resistance, and flame retardancy of these composites were investigated, and the influence mechanism was characterized by infrared spectroscopy, scanning electron microscopy, and X-ray diffractometry. The results showed that the best composite mechanical strength was achieved with 10% poplar fiber- content, and the absolute dry flexural and compressive strengths reached 3.59 and 8.06 MPa, respectively. Compared with pure gypsum, the flexural strength and compressive strength increased by 10% and 19%, respectively. The inclusion of fibers somewhat prevented the migration of free water within the composites and enhanced their water resistance. At 10% fiber content, the composite's 24 h water absorption rate was 34.3%, 8% lower than that of pure gypsum, with a softening coefficient of 0.55. However, fiber content increases the porosity of gypsum-based composites. When heated, this increased porosity accelerates' heat conduction within the matrix, raising the peak and total exothermic rates, thereby weakening the composites' inherently flame-retardant properties. Poplar-fiber-reinforced gypsum-based composites offered superior performance in commercial applications, compared to pure gypsum board, providing a sustainable and green alternative for ceilings, partitions, and other applications, while broadening the prospects for gypsum-based composites in the engineering field.

A Novel Flame-Retardant, Smoke-Suppressing, and Superhydrophobic Transparent Bamboo.

Silica glass, known for its brittleness, weight, and non-biodegradable nature, faces challenges in finding suitable alternatives. Transparent wood, made by infusing polymers into wood, shows promise but is hindered by limited availability of wood in China and fire risks associated with its use. This study explores the potential of utilizing bamboo, which has a shorter growth cycle, as a valuable resource for developing flame-retardant, smoke-suppressing, and superhydrophobic transparent bamboo. A 3-layered flame-retardant barrier, composed of a top silane layer, an intermediate layer of SiO2 formed through hydrolysis-condensation of Na2SiO3 on the surface, and an inner layer of Na2SiO3, has been confirmed to be effective in reducing heat release, slowing flame spread, and inhibiting the release of combustible volatiles, toxic smoke, and CO. Compared to natural bamboo and other congeneric transparent products, the transparent bamboo displays remarkable superiority, with the majority of parameters being notably lower by an entire order of magnitude. It achieves a long ignition time of 116 s, low total heat release (0.7 MJ/m2), low total smoke production (0.063 m2), and low peak CO concentration (0.008 kg/kg). Moreover, when used as a substrate for perovskite solar cells, the transparent bamboo displays the potential to act as a light management layer, leading to a marked efficiency enhancement of 15.29%. The excellent features of transparent bamboo make it an enticing choice for future advancements in flame-retardant glasses and optical devices.

An electrochemically mediated ATRP synthesis of lignin-g-PDMAPS UCST-thermoresponsive polymer.

It is a promising idea to graft zwitterionic polymers onto lignin and prepare lignin-grafted-poly [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (Lignin-g-PDMAPS) thermosensitive polymer with the upper critical solution temperature (UCST). In this paper, an electrochemically mediated atom transfer radical polymerization (eATRP) method was used to prepare Lignin-g-PDMAPS. The structure and property of the Lignin-g-PDMAPS polymer were characterized by the fourier transform infrared spectrum (FT-IR), nuclear magnetic resonance (NMR), X-ray electron spectroscopy (XPS), dynamic light scattering (DLS), differential scanning calorimeter (DSC). Furthermore, the effect of catalyst structure, applied potential, amount of Lignin-Br, Lignin-g-PDMAPS concentration, NaCl concentration on UCST of Lignin-g-PDMAPS were investigated. It was worth noting that polymerization was well controlled when the ligand was tris (2-aminoethyl) amine (Me6TREN), applied potential was -0.38 V and the amount of Lignin-Br was 100 mg. And the UCST of the Lignin-g-PDMAPS aqueous solution (1 mg/ml) was 51.47 °C, the molecular weight was 8987 g/mol, and the particle size was 318 nm. It was also found that the UCST increased and the particle size decreased with the Lignin-g-PDMAPS polymer concentration increased, and the UCST decreased and the particle size increased with the NaCl concentration increases. This work investigated UCST-thermoresponsive polymer which possessed lignin main chain combining the zwitterionic side chain, and provided a new way for development of lignin based UCST-thermoresponsive materials and medical carrier materials, in addition to expand the scope of eATRP.

The reconstitution of reed cellulose by the hydrothermal carbonization and acid etching to improve the performance of photocatalytic degradation of antibiotics.

As an economical and environment-friendly material, hydrothermal carbonation carbon (HTCC) has been widely used in the field of adsorption and catalysis. Previous studies mainly used glucose as raw material to prepare HTCC. Cellulose in biomass can be further hydrolyzed into carbohydrate; however, there are few reports on the direct preparation of HTCC from biomass and the relevant synthesis mechanism is unclear. In this study, HTCC with efficient photocatalytic performance was prepared from reed straw using dilute acid etching under hydrothermal conditions and was used for the degradation of tetracycline (TC). The mechanism of photodegradation of TC by HTCC was systematically elucidated through various characterization techniques and density functional theory (DFT) calculations. This study provides a new perspective on the preparation of green photocatalysts and demonstrates their promising application in environmental remediation.

Preparation of reed-based hydrothermal carbonized carbon photocatalyst and effective degradation of methylene blue and tetracycline.

Hydrothermal carbonation carbon (HTCC) is a promising semiconductor material for the photocatalytic degradation of pollutants. However, the poor charge transfer capability of HTCC and the unclear mechanism of photocatalysis limit its practical application. In this study, a novel Z-type heterojunction photocatalyst of silver carbonate (Ag2CO3) and HTCC (Ag2CO3/HTCC) was developed for the degradation of methylene blue (MB) and tetracycline (TC) from wastewater using a hydrothermal- coprecipitation method. Compared to Ag2CO3 and HTCC, 40% Ag2CO3/HTCC had excellent photocatalytic activity and stability. The free radical scavenger experiments showed that •O2- and h+ were the main substances for the degradation of MB and TC. The intermediates formed during the photodegradation were identified by HPLC-MS, and a possible mechanism and pathway for the degradation of MB and TC by Ag2CO3/HTCC was proposed. This study provides a new idea for the synthesis of Z-type HTCC heterojunction with a high-photocatalytic efficiency and its photocatalytic mechanism.

Effect of Temperature on Anaerobic Fermentation of Poplar Ethanol Wastewater: Performance and Microbial Communities.

Temperature plays an important role in anaerobic digestion (AD), and different substrates have different optimum temperatures in AD. However, the effect of temperature on the performance of AD when cellulosic ethanol wastewater was used as a substrate was rarely reported. Therefore, the digestion characteristics of cellulosic ethanol wastewater at 25, 35, 45, and 55 °C were investigated, and the microbial communities of the sludge sample were analyzed after fermentation. The results showed that the cumulative methane production was the highest at 55 °C, 906.40 ± 50.67 mL/g VS, which was 81.06, 72.42, and 13.33% higher than that at 25, 35, and 45 °C, respectively. The content of methane was 68.13, 49.26, 70.46, and 85.84% at the terminal period of fermentation at temperatures of 25, 35, 45, and 55 °C, respectively. The testing of volatile fatty acids (VFAs) indicated that the accumulation of VFAs did not occur when the fermentation was carried out at 25, 35, and 45 °C; however, the VFA content at 55 °C was much larger than that in the three groups (25, 35, and 45 °C), and the ratio of propionic acid to acetic acid was larger than 1.4 at the late stage of fermentation, so it inhibited the fermentation. The diversity of the microbial community indicated that the floral structure and metabolic pathway of fermentation were alike at 25 and 35 °C. Firmicutes and Proteobacteria were the main flora covering the 25-55 °C-based phylum or below it. The relative abundance of Methanosaeta was the highest when fermentation temperatures were 25 and 35 °C; however, its relative abundance decreased sharply and the relative abundance of Methanosarcina increased substantially when the temperature increased from 35 to 45 °C, which indicated that Methanosarcina can exist in higher temperatures. At the same time, hydrogenotrophic methanogens such as Methanoculleus and Methanothermobacter were dominant when fermentation temperatures were 45 and 55 °C, which indicated that the metabolic pathway changed from acetoclastic methanogenesis to hydrogenotrophic methanogenesis.

Constructing N-doped and 3D Hierarchical Porous graphene nanofoam by plasma activation for supercapacitor and Zn ion capacitor.

Traditional electrode materials still face vital challenges of few active sites, low porosity, complex synthesis process, and low specific capacitance. Herein, N-doped and 3D hierarchical porous graphene nanofoam (N-GNF) is created on carbon fibers (CFs) by employing a facile, fast, and environmentally friendly strategy of N2 plasma activation. After an appropriated N2 plasma activation, the graphene nanosheets (GNSs) synthesized by Ar/CH4 plasma deposition transform into N-GNF successfully. N doping donates rich active sites and increases the hydrophilia, while hierarchical nanoarchitecture exposes an enlarged effective contact area at the interface between electrode and electrolyte and affords sufficient space for accommodating more electrolytes. The as-assembled flexible N-GNF@CFs//Zn NSs@CFs Zn ion capacitor delivered a high energy density of 105.2 Wh kg-1 at 378.6 W kg-1 and initial capacity retention of 87.9% at the current of 2 A g-1 after a long cycle of 10,000.

Farmland quality assessment using deep fully convolutional neural networks.

Farmland is the cornerstone of agriculture and is important for food security and social production. Farmland assessment is essential but traditional methods are usually expensive and slow. Deep learning methods have been developed and widely applied recently in image recognition, semantic understanding, and many other application domains. In this research, we used fully convolutional networks (FCN) as the deep learning model to evaluate farmland grades. Normalized difference vegetation index (NDVI) derived from Landsat images was used as the input data, and the China National Cultivated Land Grade Database within Jiangsu Province was used to train the model on cloud computing. We also applied an image segmentation method to improve the original results from the FCN and compared the results with classical machine learning (ML) methods. Our research found that the FCN can predict farmland grades with an overall F1 score (the harmonic mean of precision and recall) of 0.719 and F1 score of 0.909, 0.590, 0.740, 0.642, and 0.023 for non-farmland, level I, II, III, and IV farmland, respectively. Combining the FCN and image segmentation method can further improve prediction accuracy with results of fewer noise pixels and more realistic edges. Compared with conventional ML, at least in farmland evaluation, FCN provides better results with higher precision, recall, and F1 score. Our research indicates that by using remote sensing NDVI data, the deep learning method can provide acceptable farmland assessment without fieldwork and can be used as a novel supplement to traditional methods. The method used in this research will save a lot of time and cost compared with traditional means.

Lake volume variation in the endorheic basin of the Tibetan Plateau from 1989 to 2019.

Lake storage change serves as a unique indicator of natural climate change on the Tibetan Plateau (TP). However, comprehensive lake storage data, especially for lakes smaller than 10 km2, are still lacking in the region. In this dataset, we completed a census of annual relative lake volume (RLV) for 976 lakes, which are larger than 1 km2, on the endorheic basin of the Tibetan Plateau (EBTP) during 1989-2019 using Landsat imagery and digital terrain models. Our method first identifies individual lakes, determines their analysis extents and calculates annual lake area from Landsat imagery. It then derives lake area-elevation relationship, estimates lake surface elevation, and calculates RLV. Validation and comparison with several existing datasets indicate our data are more reliable and comprehensive. Our study complements existing lake datasets by providing a complete and long-term lake water volume change data for the region.

Synergistic modification of polylactic acid by oxidized straw fibers and degradable elastomers: A green composite with good strength and toughness.

Polylactic acid-based (PLA) composites are widely used in biomedicine, electrical components, food packaging and other fields, but their unsatisfactory mechanical properties such as high brittleness and poor toughness, cause problems in functional applications. This work developed a green and environmentally friendly strategy to improve PLA mechanical properties. Flexible polybutylene succinate (PBS) and alkaline hydrogen peroxide (AHP) treated straw fibers (SF) synergistically modified PLA. AHP is decomposed into a large amount of HOO-, which oxidizes the hydroxyl groups in SF to carboxyl groups to obtain oxidized straw fiber (OSF), which reacts with PLA in the molten state to form new ester bonds. The tensile strength of the OSF/PLA composite is 41.78 MPa, 38 % higher than the SF/PLA composite. The impact toughness of OSF/PBS/PLA composite is 14.47 KJ/m2 increased by 54 % after the adding PBS, while the tensile strength was also better than the control group. The synergistic action of PLA and PBS in OSF is attributed to the formation of new chemical bonds, efficient crystallization, and compatible interface. This study provides a new strategy to produce fiber-reinforced PLA composites with good toughness. It takes positive significance for developing degradable plastics with good performance and controllable cost.

Effect of different amounts of bamboo charcoal on properties of biodegradable bamboo charcoal/polylactic acid composites.

Biodegradable composites were prepared from polylactic acid (PLA) and bamboo charcoal (BC) by melt blending and hot pressing. The effects of BC addition on the mechanical properties, water absorption, DMA, TGA, DSC, and CONE of BC/PLA composites were investigated. The microscopic morphology of the composites was analyzed by SEM. The results showed that for BC addition of 40 wt%, the mechanical strength, thermal properties, and flame retardant properties of the composites were improved compared with those of PLA, with a 2.24 % increase in flexural strength and a 1535 % increase (500 °C) in TG mass retention rate. The crystallinity increased by 129.66 %, the peak loss factor decreased by 31.15 %, the time required for combustion was delayed by 168 s, the peak heat release rate decreased by 29.40 %, the carbon residue rate detected by cone calorimetry increased by 48.50 %, and the peak mass loss rate decreased by 48.82 %. The addition of BC enhanced the crystallization capacity of PLA, and improved the thermal properties and flame retardant properties of the prepared composites. The results showed that materials prepared with a BC content of 40 wt% exhibited the best overall performance.

Effects of Reed Biochar Mass Fraction on the Properties of Polypropylene/Reed Char Composites.

Reed charcoal/polypropylene (RC/PP) composites were prepared by melt-blending and molding processes. The effects of RC addition (by mass fraction) on its mechanical properties were investigated and the mechanism characterized. The results showed that RC and PP were physically bonded and formed a mechanical interlocking matrix. The water absorption rate of these composites was <1% at 168 h. As the RC mass fraction increased, the tensile modulus, crystallinity, and energy storage modulus of the composites increased and then decreased, with the tensile modulus reaching a maximum of 679.4 MPa. The thermal decomposition rate peak and starting melt temperature increased by 14.8 and 2.5 °C, respectively, compared to pure PP, and the energy storage modulus reached a maximum of 3752.8 MPa at 40 wt% RC. The addition of RC in appropriate amounts improved the rigidity and thermal stability of these composites.

Influence of Alkali Treatment on Properties of Bamboo Portland Cement Particle Board.

Bamboo contains water-soluble saccharides and carboxylic acid which have an anticoagulation effect on Portland cement; the anticoagulation ingredients can directly influence the adaptability of the Portland cement and bamboo shavings and finally influence the mechanical properties of bamboo Portland cement particle board. In order to improve the adaptability of bamboo and the Portland cement, bamboo shavings are pretreated with 1% NaOH solution, 2% NaOH solution, or 3% NaOH solution. High-performance liquid chromatography is adopted to analyze the influences of treatment based on different concentrations of NaOH solutions on the content of water-soluble saccharides and carboxylic acid in the bamboo shavings, and a Fourier infrared spectrometer and an X-ray diffractometer are utilized to analyze the characteristic peak changes and crystallization property changes, respectively, of the chemical ingredients of the bamboo shavings before and after the three types of pretreatment. This paper discusses the effects of treatment based on different concentrations of NaOH solutions in eliminating water-soluble saccharides and carboxylic acid in the bamboo shavings, details the preparation of bamboo Portland cement particle board by use of the bamboo shavings before and after pretreatment, and reports the influences and mechanisms of NaOH pretreatment on properties of the bamboo Portland cement particle board. Research indicates that the mechanical properties of the Portland cement particle board prepared from bamboo shavings treated with 3% NaOH solution exceed the requirements of qualified products and superior products specified in the Standard GB/T24312-2009.

Biomimetic Swallow Nest Structure: A Lightweight and High-Strength Thermal Insulation Material.

A common method for reducing carbon emissions and the load-bearing pressure of buildings, and while also achieving improved energy conservation is to prepare porous magnesium-based lightweight composites to reduce waste and environmental hazards. However, due to internal stress, the pores of traditional lightweight composites crack easily and collapse, resulting in composites that are brittle with poor water resistance. These materials cannot achieve both low density and high strength, which limits their application in advanced functional materials. Thus, learned from nature, inspired by swallow's nest, a solution has been proposed, which is a simple and fast chemical arrangement and assembly method. Using bamboo scraps as the supporting framework and methylcellulose (MC) molecular chains as the templates, 5-phase crystals are grown and arranged on the MC. These crystals are arranged on the bamboo scraps by chemical means with MC acting as a bridge. At the same time, using the high viscosity and flexibility of the vinyl acetate/ethylene (VAE) copolymer emulsion and the formation of magnesium acetate chelate from VAE and hydration products, crystals and bamboo scraps can be assembled. Through these organic-inorganic copolymers, an intercalated and integrated biomimetic swallow nest structure is formed. The biomimetic swallow nest structure composites (BSNSC) imitated the formation process of a natural swallow nest. It is a lightweight material with a thick wall, low connectivity rate, and regular shape. Its density is 0.42 g/cm3, which is still in the density class of ultralight inorganic foam materials, and its compressive strength reaches 6.5 MPa, three times that of ordinary composites. The structure has a strength-to-weight ratio 3.5 times that of ordinary composites and a thermal conductivity much lower than of other thermal insulation materials. In the future, this type of lightweight composites with high strength, high heat insulation, and low density not only functions as a good energy-saving material for buildings but also a good thermal insulation material in the aerospace field.

Terrestrial water storage regime and its change in the endorheic Tibetan Plateau.

Analogous to flow regime, this study proposed a new statistical framework to assess inter-annual and intra-annual terrestrial water storage (TWS) regime and its changes from the aspects of magnitude, variability, duration and components. The framework was applied to two endorheic basins, Inner Basin (IB) and Qaidam Basin (QB), in the Tibetan Plateau and their eight sub-regions. Our major findings are as follows: (1) TWS in the IB (2.09-2.35 mm/a, P < 0.05) and QB (0.05-0.52 mm/a, P > 0.1) increased in all seasons from 1989 to 2019 with regional climate warming and wetting. TWS showed high increase rates (>4.50 mm/a, P < 0.05) in northeastern IB but decrease rates (<-0.90 mm/a) in southern IB. Seasonal total storage in groundwater, lake, permafrost and glacier (GLPIA) also increased in both the IB (2.55-2.68 mm/a, P < 0.05) and QB (0.05-0.43 mm/a). Seasonal soil water storage (SWA) decreased in the IB (-0.39 to -0.26 mm/a) and slightly increased in the QB (0.002-0.08 mm/a); (2) Intra-annual TWS followed approximately a cosine curve. After mutation, monthly TWS showed a higher positive magnitude change (>50 mm), accompanied by a longer duration and higher variability in the IB and its northeastern sub-regions. There was a large reduction in low storage (-18.25 mm) combined with higher variability in southeastern IB; (3) SWA change dominated the storage surplus in summer (82%) and storage deficit in autumn (-78%) and winter (-51%) in the IB, while GLPIA change dominated the storage surplus in spring (57%). In the QB, TWS change was mainly contributed by SWA change in spring (94%) and by GLPIA change in summer (73%), autumn (-62%) and winter (-58%). Component contribution rates showed a significant change in spring and winter but not much change in summer and autumn, indicating that the TWS components were more sensitive to climate change in the cold season.

Degradation of urea-formaldehyde resin residues by a hydrothermal oxidation method into recyclable small molecular organics.

Urea-formaldehyde (UF) resin residues and the related product wastes as organic hazardous wastes are difficult to be biodegraded or recycled. In this research, a hydrothermal oxidation method using hydrogen peroxide (H2O2) solution has been developed for the degradation and recycling of UF resin residues. The effects of solution concentration, temperature, and time on the degradation efficiency and products of UF resin residues were studied. Under optimal conditions, i.e., 140 °C and 5 wt% H2O2 solution, over 75% of UF resin residues was degraded after 3 h. The degradation efficiency is much higher than that of the traditional hydrothermal treatment or acid hydrolysis method. In addition, results from Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectroscopy (GC-MS), nuclear magnetic resonance spectroscopy (NMR), and X-ray diffraction (XRD) confirmed that H2O2 solution degrades UF resin residues to low molecular compounds, such as alcohols, methylal, and amides. This research provides a novel and high-efficient hydrothermal oxidization process for the degradation of UF resin residues, which might be a promising environmentally friendly and low-cost method for the disposal and recycling of industrial UF resin residues.

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Ecological security is an important guarantee for the sustainable development of regional economy and society. We analyzed the change characteristics of fraction vegetation coverage (FVC) and remote sensing ecological index (RSEI) of four irrigated agriculture regions of the Loess Plateau (Yinchuan Plain, Hetao Plain, Fenhe River Valley and Weihe River Plain) based on the remote sensing data from 2000 to 2018. The results showed that the FVC decreased in the study area from 2000 to 2018. The variation trend of FVC differed among the four irrigated agricultural distribution areas. The RSEI of the whole area showed an overall downward trend, the RSEI of Yinchuan Plain (down 0.06) and Weihe River Plain (down 0.07) decreased significantly, and the RSEI of Hetao Plain remained stable. The RSEI of Fenhe River Valley showed an increased trend. The ecological stability of Yinchuan Plain and Fenhe River Valley was relatively low, the ecological environment of Hetao Plain was relatively stable, and the ecological environment of Weihe River Plain continued to degrade. The results were important for regional ecological environment protection and agricultural sustainable development.

Research on the Compatibility of Bamboo and Portland Cement.

This paper researches the compatibility of bamboo and Portland cement by measuring the hydration temperature of Portland cement. Meanwhile, bamboo shavings and Portland cement, which were utilized as main raw materials, were prepared into bamboo Portland cement particle boards through cold compression forming, so as to further verify the compatibility of bamboo and Portland cement and research the practicability of preparing bamboo Portland cement particle boards by using bamboo. Research studies show that bamboo contain water-soluble saccharides, such as polysaccharide, disaccharide, and glucose, and organic carboxylic acids, such as formic acid and acetic acid. Water-soluble saccharides are converted into saccharic acid after dissolving in water, then a saccharide-calcium complex with a pompon-like structure is formed through a reaction between saccharic acid and calcium ions of Portland cement hydrates, and the saccharide-calcium complex covers the surfaces of the cement particles and prevents further hydration of the cement, achieving a certain anticoagulation effect on Portland cement; a chelation reaction between the carboxyl of the organic carboxylic acid and the calcium ions of Portland cement hydrates takes place and the concentration of calcium ions in the hydration system is reduced, which exerts an influence on further hydration process of Portland cement and achieves a certain anticoagulation effect. Because of the poor compatibility of Portland cement and bamboo, the physical and mechanical properties of bamboo Portland cement particle boards prepared from bamboo shavings and Portland cement directly cannot meet the requirements of the national standards (GB/T24312-2009) of cement particle boards.

Effect of silane coupling agent on compatibility interface and properties of wheat straw/polylactic acid composites.

To improve the performance of wheat straw/polylactic acid (WS/PLA) composites, four different silane coupling agents were used for constructing compatible interfaces and then examined by scanning electron microscopy, Fourier transform-infrared spectroscopy, X-ray diffractometry and thermogravimetric analysis. The blending and tensile strengths of silane-modified composites were effectively enhanced, with KH-570-modified composite exhibiting the best blending and tensile strengths. Water resistance analysis of silane-modified composites was reduced and contact angles larger, indicating that water resistance performance of this composite had been effectively improved. The KH-570-modified composite exhibited the best water resistance performance. Strain scanning showed that, in the linear viscoelastic region, the storage modulus (G') of modified composite was larger than that of unmodified composites. Frequency scanning showed that the G' and complex viscosity (η*) of modified composites were greater than those of unmodified composites. From strain analysis and frequency scanning, the modified performance of the silane agent was observed to effectively improve composite interfacial compatibility, with KH-570-modified composite exhibiting the best effect. XRD analysis showed that silane coupling agent modification improved the crystallinity of composites with the improvement of KH-570 the best. And the thermal stability of silane-modified composites was improved and the thermal stability of KH-570-modified composite the best.