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Soy protein isolate (SPI) is one of the most abundant plant proteins in nature. Enormous studies have been carried out on SPI-based materials, however, the application for energy storage devices is still limited due to its fiddly film forming process and lack of electrochemical performance. Herein, we presented a SPI-based polymer electrolyte by grafting modification with the hydrophilic functional monomer acrylamide (AM). The optimized gel polymer electrolyte (GPE) exhibited an excellent ionic conductivity up to 5.10 mS cm

Using a spatial-cueing paradigm in which trait words were set as visual cues and gender words were set as auditory targets, we examined whether cross-modal spatial attention was influenced by gender stereotypes. Results of an experiment conducted with 24 participants indicate that they tended to focus on targets in the valid-cue condition (i.e., the cues located at the same position as targets), regardless of the modality of cues and targets, which is consistent with the cross-modal attention effect found in previous studies. Participants tended to focus on targets that were stereotype-consistent with cues only when the cues were valid, which shows that stereotype-consistent information facilitated visual–auditory cross-modal spatial attention. These results suggest that cognitive schema, such as gender stereotypes, have an effect on cross-modal spatial attention.

In this contribution, a novel cellulose acetate modified with dopamine (CA-DA) membrane material was designed and prepared by a two-step route consist of chlorination and further substitution reactions. The chemical structure of the prepared CA-DA material was determined by FTIR and 1H NMR, respectively. The CA-DA ultrafiltration membrane was subsequently fabricated by the scalable phase inversion process. Compared with cellulose acetate membrane as the control sample, the introduction of dopamine improved the porosity, pore size and hydrophilicity of the CA-DA membrane, which was helpful to the water permeability (181.2 L/m2h) without obviously affecting the protein rejection (93.5%). According to the static protein adsorption and dynamic cycle ultrafiltration experiments, the CA-DA membrane displayed persistent antifouling performance, which was verified by flux recovery ratio, flux decline ratio and filtration resistance. Moreover, the water flux recovery ratio of the CA-DA membrane was retained at 97.3% after three-cycles of BSA solution filtration, which was much higher than that of the reference CA membrane. This new approach provided a long life and excellent ultrafiltration performance for polymer-based membranes, which has potential application prospects in the field of separation process.

Cellulose acetate (CA) is widely used in the preparation of ultrafiltration membranes due to its many excellent characteristics, especially chemical activity and biodegradability. To improve the inherent hydrophobic and antifouling properties of CA membrane, in this work, CA was successfully modified with dopamine (CA-2,3-DA) through selective oxidation and Schiff base reactions, which was confirmed by FTIR and

Cellulose derivatives are the earliest and most widely used membrane materials due to its many excellent characteristics, especially chemical activity and biodegradability. However, the hydrophobic properties of cellulose acetate (CA) limited its development to some extent. To improve the inherent hydrophobic and antifouling properties of the CA membrane, CA was successfully modified with dopamine (CA-2,3-DA) through selective oxidation and Schiff base reactions in this work, which was confirmed by 1H NMR and FTIR measurements. And then, the CA-2,3-DA membrane with high water permeability and the excellent antifouling property was prepared by the phase inversion method. Compared with the primordial CA membrane, the CA-2,3-DA membrane maintained a higher rejection rate for BSA (92.5%) while greatly increasing the pure water flux (167.3 L/m2h), which could be overcome the trade-off relationship between selectivity and permeability of the traditional CA membrane to a certain extent. According to the three-cycles dynamic ultrafiltration and static protein adsorption experiments, the CA-2,3-DA membrane showed good long-term performance stability and superior antifouling performance, which was supported by the experiment results including filtration resistance, flux decline ratio and flux recovery ratio. It is expected that this approach can greatly expand the high-value utilization of modified natural organic polysaccharides in separation engineering.

Isocyanate is an extremely high activity compound that has been extensively used in the chemical materials. In this study, we employ microcapsules in preserving the activity of isocyanates and controlling their release in wood adhesives for plywood. Isocyanate microcapsules were synthesized by a one-step interfacial polymerization in an oil-in-water (O/W) emulsion. The particle size distribution, chemical structure, morphology, activity and stability of the obtained isocyanate microcapsules were characterized by laser particle size analyzer, n-dibutylamine titration, FTIR, SEM, and a universal strength testing machine. The as-synthesized microcapsules had approximately 25% active –NCO group and the core accounted for 77% of the total weight. The isocyanate microcapsules demonstrated satisfactory stability by preserving majority of the active –NCO group and core weight during 180 days of storage. These isocyanate microcapsules were used as functional crosslinking agent for making plywood. The resultant plywood showed higher tensile shear strength than the strength mandated in the Chinese National Standard (GB/T 9846-2015). Furthermore, the wet strength was greatly improved to meet the Class I and II plywood standards. Additionally, the stability of isocyanate microcapsules in wood adhesives were significantly enhanced for a prolonged application time. Their excellent bonding properties and stability make isocyanate microcapsules an ideal additive for use in chemical and manufacturing materials.

In this study, controlled-release isocyanate microcapsules were synthesized as functional crosslinking to slowdown the rate of cross-linking reactions. The isocyanate microcapsules were prepared by...

Purpose The purpose of the study was to prepare melamine-urea-formaldehyde (MUF) resin that would be resistant to boiling water and high temperature and exhibit low formaldehyde emission. Design/methodology/approach The authors prepared MUF resin with different F/(M + U) and changed the amount of melamine added, through the analysis of MUF resin properties to get the best reaction parameters, and used different amino acid cure systems including NH4Cl cured the resin. Findings Resin’s heat resistance and water resistance are mainly determined by the amount of melamine added, and formaldehyde emission of the plywood can be changed by adjusting F/(M + U). The peak temperature of the curing agent-cured resin increases as compared with the self-curing resin. Stronger the acidity of curing agent, faster the viscosity increased in probation period and lower the bonding strength and heat resistance of the resin. Research limitations/implications Melamine improves the heat resistance and water resistance of the resin. When the amount of melamine is more than a certain value, water resistance of the resin decreased. Practical implications MUF resin that is resistant to boiling water and exhibits low formaldehyde emission can be used in high temperature, high humidity and strict formaldehyde emission environment and can also be combined with other materials. Social implications It was helpful to reduce the effect of formaldehyde emission on people’s health and environmental pollution and is also beneficial for the expansion of the application range of aldehyde resin. Originality/value The originality is twofold: the influence of the acid strength of curing agent on the bonding strength of the resin adhesive and the method for preparing high performance MUF resin by following the traditional process.

Natural catalysts (dolomite and olivine) not only reduce the tar content, they also have a high potential to enhance hydrogen production during gasification process. In this study, a bubbling fluidized bed (BFB) was used to evaluate the effect of the operating parameters on co-gasification of pine sawdust and brown coal namely gasification temperature (Tg) in the range of 700–1000 °C, fuel particle size (dp) in the range of 2.0–3.5 mm, steam/fuel ratio (S/F) in the range of 0.5–0.8, equivalence ratio (ER) in the range of 0.1–0.4, biomass ratio (BR) in the range of 0.0–100%, and catalyst loading in the range of 3.0–12.0 wt%. With increase in catalyst loading from 3.0 to 12.0 (wt %), the hydrogen yield was increased from 52.9 to 55.5 (g/kg-fuel) for dolomite and from 47.5 to 52.1 (g/kg-fuel) for olivine, while the tar yield sharply decreased from 5.4 to 0.4 (g/Nm3) and from 7.0 to 0.8 (g/Nm3), respectively. Fuel particle size showed a negligible influence on the upgrading of hydrogen production and tar yield.

In order to compare the performance of the neat epoxy-amine network and the same network with dispersed multi-walled carbon nanotubes. The curing reaction, rheology, thermal and electrical conductivity, mechanical performance and microstructure of epoxy-amine systems were investigated in this study. The curing schedule of the epoxy-amine systems was formulated depends on the parameters of the curing reaction. The processing windows and processing time of epoxy-amine systems were provided by using rheological analysis. The thermal and electrical conductivity of epoxy-amine network with dispersed multi-walled carbon nanotubes were enhanced. The mechanical performance of the epoxy-amine network was improved after introducing the dispersed multi-walled carbon nanotubes.

An environmentally friendly starch-based wood adhesive was developed using cassava starch (CS) and polyvinyl alcohol (PVOH). A set amount of polymethylene polyphenylene isocyanate (PAPI, modified in the laboratory) was used as the cross-linking agent to improve the water resistance. To evaluate the mechanical properties of the adhesive, the shear strength was measured by a mechanical testing machine. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) were used to characterize the properties of the adhesive and the curing products. The results indicated that the adhesive using PVOH with a low alcoholysis degree was better than high alcoholysis degree and adding 7 wt% PVOH1 (RS-1717) could obtain good mechanical properties; the dry shear strength was 7.77 MPa, reaching 1.36 MPa in the wet state. The favorable results were attributed to reactive hydrogens in the wood and CS, which can form a cross-linking network with the -NCO groups of PAPI to obtain excellent shear strength and water resistance.

In order to overcome the weakness of the epoxy-amine network, the acrylic tri-block copolymer (BMG) and the functionalized multi-wall carbon nanotubes (MWCNTs) were prepared in this article. The cu...

This study aims to access the durability of sustainable poly (lactic acid) (PLA) composites with the presence of starch and wood flour by using artificial weathering method. Chain scissions such as photolysis and hydrolysis resulted in significant decrease in molecular weight. After artificial weathering, thermal stability decreased for all materials, but very slightly for WF/PLA composite. Both the changes of molecular weight and thermal stability revealed that the weathering rate followed the order: PLA > starch/PLA > WF/PLA, indicating that starch and wood flour improved the durability of PLA. Tensile test suggested that the PLA composites introduced in starch and WF had a better environmental survivability. At last, mathematical models were established to evaluate the decrease in tensile strength with weathering. The obtained results offer an opportunity to estimate the material's durability, and provide an idea to design sustainable PLA-based materials with enhanced durability for outdoor application.

In this paper, electrospun chitosan (CS)/poly(vinyl alcohol) (PVA)/graphene oxide (GO) nanofibers were fabricated. Prepared nanofibers have been characterized and investigated for their morphological, structural, and thermal stability, and mechanical and hydrophilic properties. The uniform and defect-free nanofibers were obtained and GO, shaping spindle and spherical, was partially embedded into nanofibers, as shown in SEM. The hydrogen bonds between CS molecules and PVA molecules were easily formed due to the great compatibility of CS and PVA. The addition of GO interrupted the hydrogen bonds between CS molecules and PVA molecules, and the new interaction was formed among CS, PVA, and GO. Thermogravimetric analysis indicated that as the increasing of content of GO, the thermal stability of nanofibers decreased. More interestingly, the static mechanical properties tests and dynamic mechanical analysis all showed that the modulus of nanofibrous mats increased firstly and decreased subsequently with the increasing of content of GO, which could be concerned with the looser arrangement of nanofibers. The water contact angle of nanofibrous mats increased with the increasing of content of GO. Nevertheless, when the content of GO was up to 2.5 wt%, the water contact angle decreased significantly.

To improve the performance of waterborne materials, this study attempts to prepare a novel water-dispersible isocyanate crosslinking agent based on plant-based castor oil. The intermediate maleated castor oil and water-dispersible isocyanates with different R values [n(NCO)/n(OH)] are prepared and characterized by FTIR and 1H NMR. The viscosity test, isocyanate content titration, particle size analysis, and the morphologies indicate that the optimal condition for the water-dispersible isocyanates (e.g., best storage stability and particle size distribution) is at R value = 40. The mechanical test proves that the water-dispersible isocyanates can greatly improve the bonding strength and water resistance of wood adhesives, showing an increase of wet strength to be as high as 146 % and 506 % for urea-formaldehyde resin and white latex, respectively. The castor oil-mediated water-dispersible isocyanate system opens a novel avenue to synthesize waterborne crosslinking agent for applications in adhesives, coatings, and structural materials.

Zwitterionic polymers have attracted widespread attention and are recognized as ideal materials in various potential applications of membrane-based separation due to its superior hydrophilicity and excellent antifouling properties. Therefore, a new type of bisphenol monomer with two tertiary amine groups named 2,2'-dimethylaminemethylene-4,4'-dihydroxydiphenylmethane (DABPM) was particularly designed and prepared. Then, the novel poly(aryl ether oxadiazole) (ZPAEO) was synthesized by low-temperature polycondensation and quaternary amination reaction. The chemical structures of the synthetic monomer and polymers were characterized by MS NMR and XPS analysis, and the inherent viscosities, molecular weights and solubility behaviors of the obtained polymers were also thoroughly studied. Subsequently, the ZPAEO membrane was fabricated by through the immersion precipitation phase inversion method. Compared with the reference PAEO membrane, the pore size, porosity and hydrophilicity of the ZPAEO membrane were greatly improved because of the existence of zwitterionic groups, resulting in a significant increase in the water permeability. The results of static adsorption and dynamic cycle ultrafiltration experiments of bovine serum albumin (BSA) solution showed that the ZPAEO membrane had excellent antifouling performance, which was demonstrated by the flux decline ratio. In addition, water flux recovery ratio of the ZPAEO membrane was retained at 97.7% after a three-cycles of BSA solution filtration, which was much higher than that of the PAEO membrane (81.2%), indicating superior long-term performance stability. As a membrane material, ZPAEO is expected to be widely used in various industrial separation and purification fields, which can be demonstrated by these findings.

A bis-hydroxy terminated polyphenylene oxide (MPPO) modification was tried for the purpose of simultaneously enhancing the processability and heat resistance of epoxy resin. The thermal stability, ...

To investigate the effects of acidity on aromatic yield and selectivity during the catalytic pyrolysis of biomass, the silica to alumina ratio (SAR), as well as the amount and addition method of HZSM-5 catalyst were varied. The results showed that with an increase in the SAR, the pore volume was reduced, the average pore diameter of the HZSM-5 catalyst increased, and the total acidity and catalytic activity decreased. Meanwhile, the increase in acidity led to an increased non-condensable gases yield, which was associated with a decrease in the bio-oil yield. The calorific value and moisture content increased, and the ability of deoxygenation was enhanced. The single ring aromatic hydrocarbons (BTXE) content increased, and the polycyclic aromatic hydrocarbons (2-ring, 3-ring) content decreased noticeably. The selectivity of BTXE decreased substantially from 69 wt.% to 6.85 wt.%, while the selectivity of naphthalene and its derivatives increased remarkably, as the SAR increased. Additionally, the acidity increased the selectivity of unsubstituted aromatic compounds, but decreased the selectivity of substituted aromatic compounds. Moreover, ex situ catalytic pyrolysis more effectively enhanced the aromatic hydrocarbon yield and selectivity (69 wt.%) compared with in situ catalytic pyrolysis (27.51 wt.%), and in situ catalytic pyrolysis generated more polyaromatics and solid residue.

The molecular characteristics (molar mass, hydrodynamic radius, and electrical potential) of gum arabic, corn fiber gum, and beet pectin dissolved in aqueous solutions were measured using size-exclusion chromatography and electrophoresis. Corn fiber gum and beet pectin had extended molecular structures that entrained large quantities of water, whereas gum arabic had a more compact structure. The effectiveness of the polysaccharides at increasing solution viscosity and promoting depletion flocculation decreased in the following manner: beet pectin > corn fiber gum > gum arabic. Mathematical models were used to relate differences in the molar mass and hydrodynamic radius of the polysaccharides to their ability to thicken solutions and promote depletion flocculation. There was good qualitative agreement between the models and experiments, but relatively poor quantitative agreement. The information obtained in this study may be useful for selecting appropriate natural emulsifiers to utilize in emulsion-based products.

Biodegradation behavior of biodegradable starch/wood power/polylactic acid (PLA) composites from the natural northeast Chinese soil environment was investigated in this study. The microstructural changes of the materials for 105 days was comprehensively characterized by X-ray diffraction (XRD), Differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR). XRD results showed that the crystallinity of the composites increased at the initial soil burial period, followed by a decrease during the degradation period. DSC of the surface and interior of the composites at different degradation times further characterized the changes in composite microstructures. After degradation, short molecular chains were formed, which slowly gained various extents of chain mobility. FTIR analysis indicated that the random fracture sites of PLA and starch were C=O and C-O groups, respectively. The absorb intensity of C=O and C-O groups decreased with the prolonged degradation time. The P-S5W5 showed a higher degradation rate than others, likely due to the synergetic effect between starch and wood power.

Composites of poly(lactic acid) with wood flour which was grafted by melt extruding with methyl acrylate in the presence of benzoyl peroxide (BPO) were investigated. The modification of filler (WF-g-PMA) was carried out to enhance the filler-matrix interactions, while the treated component was characterized by infrared spectrum. Properties of binary (PLA/WF, PLA/WF-g-MA) composites were analyzed as a function of the grafting monomer amount by scanning electron microscopy, differential scanning calorimeter, thermogravimetric analysis, water absorption and mechanical tests. Compared with the untreated system (PLA/WF), all treated composites showed higher interfacial compatibility as a result of chemical bonding between WF and grated monomer. All composites showed higher tensile modulus and lower strength and elongation at break as compared to pure PLA; grafting modification with methyl acrylate led to an increased stiffness and decreased water absorption of the composites because of an enhanced fill...

The main objective of this work was to study aromatics production via the catalytic pyrolysis upgrading of biomass using metal-loaded modified H-ZSM-5. M-ZSM-5 catalysts were prepared through the impregnation method with Zn, Ga, Ni, Co, Mg and Cu. The prepared M-ZSM-5 catalysts were evaluated by x-ray diffraction, thermal desorption spectroscopy and scanning electron microscopy. The properties, composition and product distribution of bio-oil were also analysed. Results showed that the M-ZSM-5 catalysts yielded a higher amount of non-condensable gas at the expense of the liquid yields. The Ga-ZSM-5 catalysts produced the highest yields of bio-oil (25.76 wt%), but the lowest amount of coke (22.08 wt%) compared with the unmodified ZSM-5 catalyst (33.38 wt%). The content of the single-ring aromatics prepared by using the Zn-ZSM-5 catalysts was the highest at 90.28 wt%, whereas that of the polycyclic aromatic hydrocarbon prepared by the Ni-ZSM-5 catalysts was the highest at 31.36 wt%. Moreover, the selectivity of the single-ring aromatic hydrocarbons, such as C7 and C8, were significantly affected by the use of the M-ZSM-5 catalysts. The Zn-ZSM-5 catalysts were the most selective for toluene and xylenes with contents of 36.52 wt% and 35.32 wt%, respectively, whereas the Co-based catalysts were the most selective for indene. The Ni-based catalysts can obviously improve the selectivities of benzene production and C10+ polycyclic aromatic hydrocarbons. Zn-ZSM-5 was the most effective catalyst that can be used in the production of aromatic hydrocarbons.

Effect of accelerated weathering time and glycerol on the photodegradation behavior of starch/wood flour/PLA composites was studied. The decreased intensity of diffraction peaks characterized by XRD indicated that the crystal structure was damaged. The chemical structure changes characterized by FTIR showed the formation of carboxylic acid. The decreased extent of the C O absorbance intensity of the composite with 15% glycerol proved that glycerol had a stabilize effect on the UV durability of the composites. After weathering, the maximum decomposition temperature decreased prominently due to the chain cleavage. With the prolonged weathering time, the tensile and flexural strengths decreased gradually.

Purpose The purpose of this paper is to obtain high-solids-content and low-viscosity starch adhesive, and improve bonding strength of the pure starch adhesive. Design/methodology/approach Maize starch was treated by hydrochloric acid solution with different concentrations, and acid-thinned starch adhesive was prepared. Polyisocyanate as a crosslinking agent was added to improve water resistance of the pure starch adhesive. Findings The physical and chemical properties of the acid-thinned starch adhesive were characterised. Acid hydrolysis did not change structure of starch granules, but increased its crystallinity. After acid modification, starch granules became less smooth and some fragments appeared. Acid treatment had little influence on thermal stability of starch, when acid hydrolysis was not strong. High concentration of HCl solution led to starch granules being destroyed, resulting in decrease in bonding strength. The optimal HCl concentration was 0.5 mol/L. Polyisocyanate addition was beneficial to improve the bonding strength of the acid-thinned starch adhesive. Research limitations/implications Acid hydrolysis changed the properties of the starch adhesive. Practical implications Acid hydrolysis decreased viscosity of the starch adhesive and improved its solids content, which had a positive effect on the application of the starch adhesive. Social implications It was helpful to develop an environment-friendly, natural polymer-based wood adhesive. Originality/value The properties of acid-thinned starch and acid-thinned starch adhesive were studied.

A crosslinked membrane based on renewable, degradable and environmentally friendly soybean protein isolate was formed by solution casting method. A series of gel polymer electrolytes were prepared with the crosslinked membranes saturated with 1 mol&middot, L&minus, 1 Li2SO4. The solid-state electric double-layer capacitors were fabricated with the prepared gel polymer electrolytes and activated carbon electrodes. The optimized solid-state supercapacitor delivered a single electrode specific capacitance of 115.17 F&middot, g&minus, 1 at a current density of 1.0 A&middot, 1, which was higher than the supercapacitor assembled with the commercial separator in 1 mol&middot, 1 Li2SO4. The solid-state supercapacitor exhibited an outstanding cycling stability, indicating that the gel polymer electrolyte based on the crosslinked soybean protein isolate membrane could be a promising separator for a solid-state supercapacitor.

In this paper, a benzoxazine-based (BZ) adhesive with high temperature resistant was developed by blending benzoxazine monomer and tetrafonctional epoxy monomer as matrix modifier and polyetherimide as toughening agent. The results show that benzoxazine-based film adhesive could be cured at 190 °C, and the cured film adhesive exhibited high temperature resistance and a high glass transition temperature of 224 °C. The 5% weight loss temperature in air was 400 °C and the char yield in nitrogen at 800 °C was 48%. The cured film adhesive has good ablation resistance. The fabricated benzoxazine-based film adhesive has high adhesion reliability, with single-lap shear strength of 23.20, 28.36 and 20.04 MPa at room temperature, 140 and 175 °C respectively. The curing process of the film adhesive matches well with that of carbon fiber reinforced BZ prepreg and the film adhesive has stable adhesion properties. Its biggest advantage is that, during storage and transportation, there is no need of refrigeratio...

The synthesis of structured latex particles containing hydrophilic poly(vinyl acetate) (PVAc) cores and hydrophobic poly(styrene) (PS) shells mediated by a controllable transition layer was reported. A transition layer was fabricated onto PVAc cores by introducing a coupling monomer and butyl acrylate (BA), prior to polymerization of second-stage St-based monomer mixture. While such structured PVAc/PS latex particle obtained was thermodynamic non-equilibrium, straightforward synthetic route of the transition layer can be optimized so that the particle morphology is kinetically achievable. Analysis by transmission electron microscopy shows that the particle morphology is highly influenced by both the transition layer composition and PS-based polymer composition. Two-phase particle morphology without transition layer was an inverted acorn-like structure with single PS core wrapped by PVAc shells. The particle morphology mediated by transition layer varied from that of a broken egg shell-like structure with PS-based coating, over intermediate structures in which uniform PS protuberances surrounded PVAc cores, to core/shell structure with single PVAc core. This general approach may offer a number of possibilities for design and synthesis of kinetically controllable phase-separation morphologies for a variety of applications.

Multiwalled carbon nanotubes (MWCNTs) that were treated with mixed acids were used to reinforce the cyanate ester resin. Meanwhile, the relationship among structure, morphology, and property of the modified resin was investigated. The treated MWCNTs were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis, and X-ray photoelectron spectroscopy (XPS). The XPS results showed that the oxygen content in the treated MWCNTs was higher than that of untreated MWCNTs and the FTIR results indicated the presence of oxygen-containing functional groups on the treated MWCNTs. The microstructure of the resin was characterized by scanning electron microscopy and transmission electron microscopy. The results showed that the dispersion properties of the treated MWCNTs in the resin matrix were improved and compared with the untreated analogue. Addition of MWCNTs to the resin had little effect on the thermodynamic properties of the resin system. Upon addition of 0.8 wt% of MWCNTs to the resin, the glass transition temperature of the cured resin changed from 298°C to 285°C, maintaining a relatively high value. For the resins containing 0.6 wt% of treated MWCNTs, the plane strain critical stress intensity factor and plane strain critical strain energy release rate in the system were determined to be 1.39 Pa·m0.5 and 364 J m−2, respectively, and the fracture toughness is increased by 45.7 and 76.0%, respectively. Furthermore, the modified resin system exhibits excellent toughness and thermal properties. Therefore, the modified resin may be suitable for future applications involving high performance composites and adhesives.