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To control road dust pollution, a starch/organo-bentonite composite liquid dust suppressant (CLDS) was successfully prepared. Potato starch was dissolved with NaOH solution at room temperature, and then sodium bentonite modified with cetyltrimethylammonium bromide (CTAB-bentonite) was incorporated before polymerization reaction. The CLDS was characterized by XRD, FTIR, TG and SEM. Its properties, dust-suppression performances, dust removal effects and economic feasibility had also been evaluated. The results suggested CLDS presented a porous three-dimensional network structure with numerous layers and folds, and residual CLDS could form a protective solidified layer together with dust via high viscosity after solidification, which effectively enhanced the absorption of CLDS on dust, delayed its water evaporation, and inhibited dust diffusion under windy weather. CLDS also had good thermal stability and biodegradability due to the addition of CTAB-bentonite. 2.5 wt% CLDS can dramatically improve dust-suppression effect and overcome dust resuspension problem to save water consumption and bring economic benefits.

Air pollution by dust particles is a major health concern in urban and industrialized areas. Actual methods to reduce dust contamination, such as water spraying, are limited, calling for new dust suppressants. Here, we synthesized a liquid starch-based dust suppressant by grafting polyacrylic acid onto NaOH-pretreated potato starch and then crosslinking the grafted copolymer with gelatine. This dust suppressant was characterized by Fourier-transform infrared spectrometry, thermogravimetry, viscosity and contact angle measurements. We also measured permeability, water retention, anti-wind erosion and degradability of the dust suppressant. Field experiments tested the dust suppressing effect on particle matter 2.5 (PM2.5) and particulate particle matter 10.0 (PM10). We found that the addition of NaOH to potato starch improved the reaction efficiency and simplified the preparation process. The dust suppressant demonstrated excellent degradability, as shown by weight loss of 82 wt % after 60 days of soil burial, and the total dust suppression rates reached 57% for PM2.5 and 56% for PM10 in the field. Compared with spraying water, total dust suppression was higher by 25% and 33%, respectively.

The objective of this study was to develop the efficient methods for dialdehyde cellulose (DAC) production, in which periodate solution was used as oxidant, and an electrochemically assisted system was applied to achieve green, efficient, low-cost and sustainable oxidization of cellulose. The microcrystalline cellulose (MCC) was pre-treated by alkali or ultrasound, and then oxidized to prepare DAC in the electrolyzer with aqueous solution of sodium periodate. Finally, the DAC was obtained by centrifugation and lyophilization. The prepared DAC materials were characterized by FTIR, XRD and SEM, and analyzed via aldehyde group contents, crystallinity index, water solubility index and water retention value. The introduction of active functional groups promoted cellulose hydration and swelling. Compared to the ultrasound pretreatment, the alkaline pretreatment had a great influence on the water solubility index and water retention value of cellulose. The aldehyde group contents of DAC increased after the MCC was oxidized by sodium periodate in the electrolyzer. Electrochemically assisted oxidation significantly decreased the crystallinity of the DAC, and the surface structure was smooth and soft, which can be attributed to the electrochemically assisted reaction that could regenerate the spent periodate in anode electrolytic chamber. When DAC was prepared under optimal conditions (current density: 0.075 A/cm2, periodate concentration: 0.6 mol/L, reaction time: 30 min), the regeneration efficiency of spent periodate reached about 93.4%.

Low-molecular-weight keratin (LMWK) obtained from wool was employed as a wall material for the spray drying encapsulation of fish oil. Microcapsules with different LMWK contents were prepared, and their anti-ultraviolet performance and other features were studied. The results showed that LMWK was able to improve the encapsulation efficiency of fish oil because of its good emulsifying properties. When the LMWK content was increased from 0 to 10, 30 and 50%, the shelf life of the microcapsules under ultraviolet irradiation increased from 48 to 96 h, 144 h and 168 h, respectively. The strongest absorption efficiency of LMWK is shown in the UVc band. The chemical structure of LMWK did not change during an ultraviolet accelerating ageing test. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-020-04897-2) contains supplementary material, which is available to authorized users.

Structural induced heat transfer capability of waterborne polyurethane (WPU) membrane was investigated. Hereby, WPU emulsions were synthesized with series of combinations of 2,4-Diisocyanatotoluene (TDI), poly(propylene glycol) (PPG), Poly(ethylene glycol) (PEG), dimethylolpropionic acid (DMPA) and ethylene glycol (EG) for studied membranes preparation. In this study, optimal prepolymer components, hard segment content, hydrophilic fragments and thermal annealing treatment on membrane-forming process were performed to study the structural features of WPU and corresponding heat conduction. Regarding to the results of AFM, XRD and DSC analysis, we found heat conduction was tightly related to the status of phase behaviors in studied WPU membranes. That's because phonon propagation as one primary heat carrier in polymer matrix was closely depended on the morphology of polymer chains. Good phase separation behavior could conduce to form long-range, short-range and microcrystalline ordering in WPU through intermolecular force (e.g. hydrogen bond), further pave as a conductive path for heat transmitting.

Waterborne polyurethanes (WPUs) with different mass ratios of soft and hard segments were synthesized by toluene diisocyanate, polypropylene glycol (PPG) and ethylene glycol (EG). It was shown that the PPG-based WPU with a mass ratio of soft and hard segments of 3:2 expressed a highest thermal conductivity (similar to 0.374 W/m.K), but showed a lowest T-peel strength (21.55 N/25 mm). As the mass ratio of soft and hard segments increased to 4:1, the T-peel strength was increased to 136.14 N/25 mm and thermal conductivity was decreased to a lowest value (similar to 0.306 W/m.K). To gain more understandings a number of analytic were carried out, such as FTIR, TG, DSC, DMA, AFM and XRD. Furthermore, mechanical properties of the PPG-based WPU coatings were tested as well. A possible explanation for the change in properties is due to the degree of phase separation and crystallinity, which was increased with the increasing of hard segment content. As a result, the hard and soft segments formed orderly oriented stacked structures by owing to the increasing of phase separation.

With the respect to research the effects of polyethylene glycol (PEG, Mw = 1000), an ordered hydrophilic fragment, on thermal conductivity of waterborne polyurethane coatings (WPUCs), the PEG–polypropylene glycol (PPG, Mw = 2000)–based WPUCs (PEG-PPG-based WPUCs) were synthesized with different combinations of PEG and 2,2-bis(hydroxymethyl)propionic acid (DMPA). The total amount of hydrophilic agent was fixed. Experiment found that the PEG-PPG-based WPUC synthesized with 13% PEG and 2% DMPA showed a highest thermal conductivity (∼0.675 W/m‧K). The phase separation, crystallinity and thermal conductivity were increased with the increasing of PEG. A number of characterizations were carried out through FTIR, TG, DSC, DMA, AFM and XRD to study the association of chemical structures and thermal conductivity at the basis of multiple combinations. The results showed that the ordered PEG fragments incorporated into WPUCs could increase the crystallinity and thermal conductivity, which was owing to the more ordered structures formed in hard phase and soft phase, and that facilitated the phonon propagation in free pathways, as a result.

One chemical sand-fixing material based on graft copolymer of gelatin (G) extracted from leather solid wastes was studied in this work. G was extracted from leather solid wastes through the method of alkaline hydrolysis firstly, and then acrylamide (AM) and acrylic acid (AA) monomers were grafted onto the G to synthesis the graft copolymer (G-g-P(AM-co-AA)) by free-radical copolymerization. The graft copolymer was purified by solvent method, after that the purified G-g-P(AM-co-AA) was characterized by FTIR, TG–DTG and other analysis technology. The results indicated that both the adsorption peaks of gelatin’ amide bond and monomer existed in infrared spectrogram proved that the AM and AA monomers have grafted with G. The thermal stability of G was improved after reacted with AM and AA monomers, and the maximum decomposition temperature was about 380 °C. The G-g-P(AM-co-AA) has good storage stability, dilution stability and temperature resistance. And the product has excellent biodegradability, which reflected better environmental protection and safety property. The G-g-P(AM-co-AA) could be combined with sand particles, and formed a consolidation layer, which has a good water retention, anti-wind erosion and anti-water erosion. When the mass fraction was 3%, G-g-P (AM-co-AA) solution can meet the requirements of sand-fixation under conventional desert environment.

Waterborne polyurethanes (WPUs) have been pushing toward more multifunctional directions developing which is due to the more extensively utilized in the world. Obviously, electronic devices are becoming more miniaturization and intelligentialize, accompanying many problems (e.g., heat dissipating and heat aging) to resolve. Organic polymers are to be good substitute for metal substrate used in devices because of their excellent performances. However, due to the most of polymers are poor conductor of heat, so many researchers utilize the hybrid method to enhance thermal conductivity of composites, through the pathway formed by fillers connection to build heat networks for phonon conduction. In this study, we do some reviews of WPU/composites on heat conducting. We put a focus on the enhancement of thermal conductivity through the compatibility and feasibility of hybrid methods, which includes the physical and chemical modification with non-covalent and covalent bond interactions. Plus, referring to laboratory previous study of heat conduction, on which pure WPU possessed with short-range, long-range ordering and microcrystal structures can facilitate the phonon conduction with the improvement of thermal conductivity.

A biodegradable film based on gelatin extracted from chrome leather scrap was studied in this paper. According to the results of a variety of characterization, the extracted gelatin contains 13 kinds of amino acid; the chrome content is 30 mg/kg, mineral and salt content are both at low levels and the nitrogen content is 43.84%. Its molecular weight has been measured at about 6.5 kDa ∼26.6 kDa, and the average particle distribution appears to be 125 nm with a narrow distribution. When the extracted gelatin was modified with the β-cyclodextrin to prepare the biodegradable films, the β-cyclodextrin and gelatin blends can build up perfect compatibility and film-forming properties. Comparing to the gelatin film without β-cyclodextrin, the viscosity, biodegradability, thermal stability and physical properties of the β-cyclodextrin and gelatin blends in the present research were significantly increased, especially when the ratio of β-cyclodextrin to gelatin was 1:2, the biodegradation rates reached 81%, elongation at break 15.74% and the tensile strength 122.34 MPa. The blends show perfect swelling properties and overcome the rapid solubility drawback of extracted gelatin.

Dust is a serious worldwide pollution, notably for nanoscale particles that are both toxic and difficult to control. Dust suppression can be done by adsorption on solid wastes, such as collagen from by-products of leather manufacturing. Here we review dust pollution and dust control, notably using collagen degradation products. Simulation experiments show that dust suppression using modified collagen degradation products reaches 68.2% for particulate matter 2.5 (PM2.5) and 78.7% for particulate matter 10 (PM10). The advantages and disadvantages of the current dust suppressors are discussed.

Noble hydrogel beads based on gelatin and oxidized corn starch were synthesized, and their usefulness and feasibility in treating effluent with dyes were studied in this work. Tartrazine was introduced as a model material. The kinetics of the tartrazine adsorption of the hydrogel beads were of a pseudo-second-order, and its adsorption isotherm is better fitted with the Langmuir model in comparison with the Freundlich model. With a pH of 2.5 coupled with a stirring speed of 400 r.p.m. and bath temperature of 35 °C, a maximum adsorption capacity of 293 mg g−1 was achieved. The hydrogel beads were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. The results revealed that the blends have a uniform porous structure and can form stable Schiff base structures. The blend also had good stability and compatibility on mixing with electrolyte solutions, and swelling behavior measurements revealed that the hydrogel beads had excellent water-absorbing capacity. The adsorption approach is considered as the most effective method of removing dyes from effluents, which among new synthetic materials become high-profile as adsorbents in recent years. This work provides a noble synergistic hydrogel beads based on oxidized corn starch (OCS) and gelatin (G). The OCS and G can form three-dimensionally cross-linked networks owing to Schiff’s base formation. This work also proved that the form of hydrogel beads can be implemented in the synergistic materials for removing dyes from effluents, which has so far been neglected in the literature.

The NaOH/urea treatment of starch results in granular cold-water-soluble starch (GCWSS). The research indicated that the optimized condition for this treatment was aqueous solution of 14% w/v NaOH and 12% w/v urea (all dosages based on starch weight) at ambient temperature (25 °C) for 10 min with stirring. The aqueous solution was then treated a water-extraction and alcohol-precipitation method. The solid sample was dried in an oven at 60 °C. The GCWSS displayed a cold-water solubility of ~90%. The GCWSS had lower amylose content. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction also indicated that it was an amorphous solid with a V-type pattern (single-helix). The NaOH/urea solution could destroy the inter and intra hydrogen bonding of starch thereby decreasing glass transition temperature, and improve the cold water solubility of native starch.

With the expect to research the influential factors to heat transfer property of waterborne polyurethane(WPU), synthesis and membrane properties of WPU are researched, to which the composition of monomers, such as the 2,4-toluene diisocynate(TDI), isophorone diisocyanate (IPDI), polypropylene glycol(PPG with Mn = 1000, 2000 g/mol), dimethylol propionic acid(DMPA) and small molecular ethylene glycol(EG) are discussed. The orthogonal experiments show that the order to affect the thermal conductivity is PPG > DMPA > R(-NCO/-OH). The differences in thermal conductivity of WPU membrane samples are expressed, wherein through DMA, DSC, TG, FTIR, AFM, and XRD analyzed. A fact that thermal conductivity has a strong correlation with crystallization behavior of WPU membrane samples. The crystallization behavior is dependent upon the degree of microphases separation between hard segment and soft segment and that all attribute to the short range, long range and microcrystalline ordering, similarly which that create a well free paths for phonon conduction and accompanying with the enhancement of heat conducting properties of WPU membranes.

Oxidized Bacterial Cellulose (OBC)-hydroxyapatite (HAp)-gelatin (Gel) nanocomposites were prepared by a biomimetic process. HAp nanocrystals were precipitated in a mixed solution of Na2HPO4 (pH 9.2) and Gel solution at 37 °C, and OBC was used to generate a three-dimensional (3D) network stent. The tensile strength of OBC-HAp-G was higher than 0.3 MPa, and the complete degradation time was approximately 90 d in Simulated Body Fluid (SBF). Fourier transform infrared spectroscopy demonstrated that a coordinate bond had formed possibly between HAp and the cellulose hydroxyl. X-ray diffraction showed that both the oxidation of bacterial cellulose and an increase in Gel content induced the formation of tiny HAp crystallites during composite fabrication. Specific surface area and porosity measurements indicated that a low Gel concentration contributed to retention of porous structure. The Ca and P contents on the surface of materials increased initially and then decreased with an increase in Gel content, as measured by energy dispersive spectroscopy. From the thermogravimetric data, the increase in decomposition temperature suggested the formation of chemical bonds among OBC, HAp, and Gel. The above results suggest that the OBC-HAp-G0.3 composite is a potential bone scaffold material.

Degraded gelatin (Gel) and oxidized corn starch (OCS) as abundant, recyclable, and biodegradable materials can be applied to agricultural production, which has been investigated in this research. Firstly, the prepared oxidized corn starch-gelatin (OCS-Gel) composite material was characterized through a Fourier transform infrared spectrometer (FT-IR), a scanning electron microscope (SEM) picture, and a thermogravimetric analysis (TGA). The OCS-Gel was then used as a liquid film mulching for agricultural production, and the application performances (hygroscopicity, permeability, water retention, etc.) of the OCS-Gel were measured. Finally, the planting rapeseed experiments were carried out, and the germination and growing state of the rapeseed seeds were observed. The results from the structural analysis indicated that OCS-Gel enriches pore structure and exhibits high thermal stability up to 324.8 °C. In the application experiments, the OCS-Gel showed excellent properties of water-absorbing and water-retention and low permeability. In addition, the germination rate of the rapeseed seed reached 80 %, and the height of rapeseeds obviously increased in pot experiments after adding the liquid film mulching.

Herein, NaOH solution of a finite concentration was used to pretreat starch, which serves a novel effective pretreatment. A starch-based high-performance adsorptive hydrogel (STAH) was successfully prepared by grafting polyacrylic acid (PAA) onto starch and then crosslinking with N,N'-methylene-bisacrylamide (MBA). This adsorbent was employed to adsorb typical organic cationic dye contaminants (methylene blue (MB)) from high concentration effluents. The effect of the pretreatment time of starch on adsorption capacity of STAH was investigated in detail based on starch molecular weight, solid state 13C nuclear magnetic resonance spectra and grafting parameters. The results suggested that the optimal adsorbent (STAH20) presented the highest grafting parameters (50.06% reaction ratio of C6 in starch, 90.79% grafting efficiency, and 248.49% grafting ratio of PAA). STAH20 exhibited maximum adsorption capacity (2967.66 mg/g) in optimal conditions and excellent reusability after 4 rounds of recycling. The adsorption process of STAH20 for MB was consistent with the Langmuir model, obeyed the pseudo-first order model with intra-particle diffusion, and was endothermic and spontaneous. Using this pretreatment, the semi-crystalline structure of starch was destroyed, and numerous hydroxyl groups were gradually exposed with time, which is conducive to the graft reactions. The number of –COOH/ –COO– groups increased, which significantly enhances the hydrogen-bonding interaction and electrostatic interaction between STAH and MB and improves the adsorption capacity. Our study provides a method for low-energy, inexpensive, effective and simple starch pretreatment for the fabrication of STAH that exhibits significant potential for application in the removal of organic cationic dye contaminants.

Waterborne polyurethane (WPU) was successfully synthesized with two ways of one-step method and two-step method, mainly focusing on the effects of asynchronous synthesis method on WPU films’ structural features and thermal conductivity. Compared to the one-step synthesis method of WPU (OS-WPU), the two-step synthesis method of WPU (TS-WPU) showed a high thermal conductivity and approximately 1.4-fold higher than OS-WPU. In addition to this, the water- and solvent-resistance properties and crystallinity of TS-WPU also displayed a better performance than that of OS-WPU. Instrumental analyses of FTIR, DSC, DMA, AFM, SEM and XRD indicated that TS-WPU had an evenly phase separation and lots of microcrystal domains, which is owing to the more ordered structures existed in hard and soft segment domains. In short, the long-range order, short-range order and microcrystal domains existed in WPU can facilitate the phonon propagation, and that is corresponding to the increasing of thermal conductivity.

An efficient method was developed to prepare oxidized potato starch under the pasting point by Electro-Fenton system, in which a complex of sodium citrate and Fe2+ (SC-Fe2+) was used as catalyst, and H2O2 was used as oxidant. In the preparation process the oxidation degree of starch was controlled by the molar ratios of SC-Fe2+ and hydrogen peroxide. The structures and thermal properties of the prepared oxidized starch were characterized by FT-IR, XRD, SEM, DSC and DTG. The characterization results indicated that the obtained oxidized potato starch owned one grainy molecule structure, and displayed a high viscosity (not less than 63 Pa·s) by comparing to the raw starch. The carbonyl and carboxyl contents of oxidized potato starch achieved 0.81 per 100 AGU and 0.79 per 100 AGU, respectively after the raw starch was oxidized. And the oxidized starch showed good thermal stability, which can dramatically improve the application performance of starch-based biomaterials.

Degraded gelatin (Gel) and oxidized corn starch (OCS) as renewable and abundant recyclable and biodegradable materials can be applied to dust mitigation, which has been investigated in this research. Blends of oxidized corn starch and gelatin (OCS-Gel) were prepared by introducing the OCS into the Gel. Sodium carboxymethyl cellulose was used as a thickener and dispersant in the blends. The OCS-Gel blends were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis (TGA). The results revealed that the blends have a uniform porous structure and can form stable Schiff's base structures. The TGA and DTGA thermograms indicated high thermal stability up to 325 °C. Moreover, the blend had good stability and compatibility by mixing with an electrolyte solution, and the biodegradability and water-sorption measurements also revealed that the OCS-Gel had excellent hygroscopicity and degradability. The results of contact angle measurements between OCS-Gel solutions and dust showed that the blends have a satisfactory effect on dust wetting, and the results of light-transmittance tests revealed that the blends had a good effect on dust-removal ability. In addition, the dust particles can be evenly adsorbed on the surface of OCS-Gel when they were evenly dispersed on the surface of the OCS-Gel solution and can then form a film. The simulation experiment for flying dust in an enclosed area indoors indicated that the dust-suppression degree for particulate matter less than 2.5 micrometers (PM2.5) and less than 10 micrometers (PM10) in size can reach 68.2% and 78.7%, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44437.

One chemical sand-fixing materials based on poly(acrylic acid)-corn starch (PACS) blend was studied in this work. The PACS blend was prepared by solution mixing method between PA and CS. In order to prepare sand-fixing materials for environmental applications using the well-established method of spraying evenly PACS blend solution on the surfaces of fine sand. Fourier transform infrared spectroscopy (FT-IR) revealed the existence of the intermolecular interactions between the blend components. Scanning electron microscope (SEM) analysis showed a continuous phase of blend, and it also showed the good sand-fixing capacity. The test results of hygroscopicity and water retention experiments indicated that the blends had excellent water-absorbing and water-retention capacity. The results of contact angle measurements between the PACS solutions and fine sand showed that the PACS blend has a satisfactory effect on fine sand wetting. And the PACS, as a sand-fixation material, has excellent sand-fixation rate up to 99.5%.