Water-absorbent Resin Research Articles

Preparation and performance of steel slag and recycled brick aggregate modified concrete under the background of solid waste application

Permeable concrete has the characteristics of breathability, permeability, and high heat dissipation. To improve its mechanical and frost resistance properties, this study optimized the preparation and performance of permeable concrete by adding materials to improve its performance. The performance analysis validate that epoxy resin owns a filling effect on the pores of permeable concrete. The internal curing agent, high water absorbent resin, has a good water absorption effect. The synergistic effect of these two increases the density and compressive strength of permeable concrete. When the two contents are 0.5%, the maximum compressive strength of modified permeable concrete at 7 and 28 days was 15.62 and 17.97 MPa, respectively. Under the action of freeze-thaw cycles, its mass loss rate show an upward trend By comparison, epoxy resin and high water absorbent resin are beneficial for improving the frost resistance of permeable concrete. The minimum value of relative dynamic modulus of elasticity remains stable at over 80%, and the loss rate of dynamic modulus of elasticity is all below 0.4. However, the influence of epoxy resin and SAP on the mass loss rate is relatively small, and the mass loss of all experimental groups is controlled below 2.5%. The binomial Fourier function model is the best predictive model for permeable concrete under freeze-thaw cycles. This study has positive significance for improving the performance of permeable concrete and maintaining the sustainable development of ecological cities.

Preparation and Performance of Resin-Gel-Rubber Expandable Lost Circulation Material Blend.

Aiming at the complex strata, lost circulation often occurs. and lost circulation control becomes a difficult issue. A drilling fluid loss accident delays the drilling progress and even causes major economic losses. If we take a self-made sodium polyacrylate grafting and modify a starch water absorbent resin, using an amphiphilic compatibilizer as raw material through mechanical blending and chemical compatibilization, we can synthesize a resin-rubber blend swelling lost circulation material. This material presents a good resistance to anti-high-temperature performance, but the quality declines while the temperature is higher than 363 °C, and with the increasing temperature, the water-swelling expansion ratio becomes higher. The range of the water-swelling expansion ratio is 8 to 25 times and the water swelling rate becomes larger along with the reduced diameter of the lost circulation materials and decreases with the increasing salinity. The resin-rubber blend swelling lost circulation material after water swelling has excellent toughness and high elastic deformation capacity, thus, forming a 7 Mpa to 2 mm fracture via expansion, extrusion, deformation, and filling, which presents a good performance for fracture plugging and realizes the purpose of lost circulation control.

Fabrication of all-starch-based hydrogels as eco-friendly water-absorbent resin: Structure and swelling behaviors

Water-absorbent resin has gained wide applications due to the capability in absorbing and retaining substantial amounts of water, while it's a challenge to fabricate a full biobased water-absorbent resin with excellent biodegradability and eco-friendliness. In this study, starch was sulfonated (SS) and crosslinked with epichlorohydrin to fabricate all-starch-based hydrogels (SSH) as water-absorbent resin with advantages of intrinsic biodegradability and low cost. The results confirmed that the hydrogen atoms of -OH groups in starch chains were partially replaced by -SO3− and the substitution degree (DS) of SS reached 0.008–0.344. By controlling DS and gelation process of SS, the swelling ratio (Qe) of SSH was improved in distilled water, reaching 244.47 g/g for samples prepared using SS with medium DS (SSMDSH). SSMDSH showed relatively loose network structure with low cross-linking density and large pore size. Meanwhile, -SO3− groups on SSMDSH chains facilitated strong ion-dipole interactions with water molecules, resulting in an increase in content of non-freezing bound water within hydrogels and thus improvement in water absorption capacity. Besides, SSH showed desired fertilizer absorption performance and complete biodegradability in α-amylase solution, which made it to be a promising candidate in agricultural fields as eco-friendly water-absorbent resin.

Study on the Inhibition of Coal Spontaneous Combustion by Superabsorbent Antioxidant Inhibitors

ABSTRACT Aiming at the problems of short inhibition life and low efficiency of physical inhibitors for the prevention and control of coal spontaneous combustion, this paper utilizes super water-absorbent (SAR) resin with tea polyphenol (TP) and vitamin C (VC) to prepare an inhibitor that can continuously and efficiently inhibit coal spontaneous combustion. Through the procedure of heating, thermogravimetric experiments are performed to characterize the inhibition performance of super-water-absorbent antioxidant-type inhibitor, and the change of active functional groups in the original coal and inhibited coal samples. The experimental results show that the super-water-absorbent antioxidant retardant can inhibit the coal spontaneous combustion in the low-temperature oxidation stage by absorbing heat through water evaporation and lowering the temperature to isolate the oxygen, and in the super-temperature stage by reducing the number of active functional groups in the coal. Compared with that of the original coal, and the water retention of the highly absorbent resin played the role of cooling and oxygen barrier for the coal; the apparent activation energy of the resisted coal samples in the spontaneous combustion in the three stages of oxygen uptake and weight gain, pyrolysis, and combustion increased by 41.02 kJ/mol, 92.58 kJ/mol, and 133.7 kJ/mol. In the process of temperature increase, the content of -OH, -CH2, -COOH, C=C, and C-H functional groups in the resisted coal samples was lower than that of the original coal, and -OH and -CH2 in the resisted coal samples showed a tendency to decrease, which reduced the reactive functional groups. Therefore, the superabsorbent antioxidant inhibitors can inhibit coal spontaneous combustion reactions by reducing the activity of coal molecules and delaying the process of coal spontaneous combustion reactions through releasing water, absorbing heat, and covering oxygen. The results of this study can be used as a reference for the field of inhibition of coal spontaneous combustion by chemical inhibitors.

Improving thermal comfort of individual wearing medical protective clothing: Two personal cooling strategies integrated with the polymer water-absorbing resin material

To limit the spread of the epidemic, healthcare workers wore tightly closed protective suits. The microenvironment with high temperature and humidity inside medical protective clothing (MPC) may result in health risks to healthcare workers associated with heat stress, particularly when exposed to high-temperature environments over extended periods. To solve the problem of poor thermal and humidity comfort in MPC, two cooling strategies were designed by selecting a polymer water-absorbent resin: hygroscopic material clothing (HMC) and condensation dehumidification package (CDP). In this regard, we conducted experiments with ten participants to explore the effects of two strategies. Two ambient conditions (Neutral–warm condition, at about 27 °C; Hot condition, at about 31 °C) and four different wearing-mode conditions were chosen for this study. The results show that both strategies can improve the microenvironment in the MPC, significantly reduce the average skin temperature of the participants, improve the thermal sensation and comfort, and reduce the discomfort caused by hot and humid environments. Under hot conditions, the two cooling strategies can reduce the average skin temperature by more than 0.2 °C. Compared with the results of the control conditions, the average TSV was reduced by 0.47 and the average TCV was increased by 0.23 at most when using HMC; The average TSV was reduced by 1.00 and the average TCV was increased by 0.38 at most when using CDP. Moreover, the effects of the two strategies on improving thermal comfort were recognized by participants.

A novel method to produce massive seedlings via symbiotic seed germination in orchids.

Orchids produce large numbers of dust-like seeds that rely heavily on orchid mycorrhizal fungi (OMFs) for germination. Using OMFs to facilitate orchid proliferation is considered an effective method for orchid conservation but still presents challenges in practice. In this study, orchid seed-fungus complexes, in which orchid seeds and fungal mycelia were embedded together to form granules, were developed as platforms to facilitate seed germination and seedling production. Overall, seedlings were produced by seed-fungus complexes for five orchid species with large variations in the percentages of seedlings produced among species/treatments. For the different fungal treatments in Dendrobium officinale, Sebacinales LQ performed much better than the other fungal strains. At 90 days after sowing, 75.8±2.6% seedlings were produced in the LQ treatment, which was significantly higher than in the Tulasnella sp. JM (22.0±3.0%) and Tulasnella sp. TPYD-2 (5.3±1.0%) treatments, as well as in the LQ and TPYD-2 cocultured treatment (40.4±3.2%), while no seedlings were formed in the Tulasnella sp. SSCDO-5 or control treatments. For the other four orchid species, only one compatible fungus for each species was used, and the percentages of seedlings in epiphytic Dendrobium devonianum (67.2±2.9%) and D. nobile (38.9±2.8%) were much higher than those in terrestrial Paphiopedilum spicerianum (2.9±1.1%) and Arundina graminifolia (6.7±2.1%) at 90 days after sowing. Adding 1% polymer water-absorbent resin to the seed-fungus complexes of D. officinale seeds with fungal strain Sebacinales LQ significantly increased seedling formation, while other additional substances showed negative effects on seedling formation. For the storage of seed-fungus complexes, it is recommended to store the seed-fungus complexes in valve bags at room temperature for a short time and at a low temperature of 4°C for no more than 30 days. As a platform for symbiotic seed germination, the seed-fungus complex can facilitate seed germination, produce seedlings and support subsequent seedling growth, and its seedling productivity depends on seed germination characteristics, seed viability, and the efficiency of fungi. Seed-fungus complexes have great potential to be used as propagules in orchid conservation.

Preparation of AMPS/CMC Modified Acrylic Water Absorbent Resin and its Application in Soil

Preparation of AMPS/CMC Modified Acrylic Water Absorbent Resin and its Application in Soil

Investigation on Surface Crack Resistance and Curing Measures of Airport Cement Concrete Pavement during Construction in Strong Wind and High Temperature Weather

The airport cement concrete pavement is prone to surface shrinkage cracks during construction under strong wind and high temperature conditions. Based on this, in this paper, the influence effects and mechanisms of curing methods on early shrinkage and crack resistance of concrete were investigated through indoor tests to simulate strong wind environment and high temperature environment in summer, and the applicability of different curing methods in engineering practice was verified by on-site experiments. The indoor experiment results demonstrated that the concrete was more prone to cracks under strong wind than under high temperature. The indoor and on-site experimental results showed that it was difficult to ensure a crack-free concrete surface by employing traditional geotextile, simply spraying curing agent or using only water-saving moisturizing curing film, among them, utilizing composite geotextile curing film has the best anti crack effect. In addition, incorporating polymer water absorbent resin enables the concrete to be cured internally, so it can be used as a supplementary curing measure to further improve the crack resistance of concrete in strong wind and high temperature weather.

Effect of Super-Absorbent Polymer (SAP) Incorporation Method on Mechanical and Shrinkage Properties of Internally Cured Concrete.

To study the effect of SAP incorporation on the early shrinkage of SAP internally cured concrete with the aim to solve the problems of early shrinkage and cracking of bridge leveling-layer concrete, using the SAP incorporation method as a parameter, the mechanical properties test of internally cured concrete, the shrinkage performance test of ring restraint and the scanning electron microscope observation test were carried out. The effects of the SAP content and incorporation method on the flowability, mechanical properties, shrinkage performance and microstructure of internally cured concrete were analyzed. The experimental results show that when the content of the SAP in concrete is 0.2% of the mass of cementitious materials, it has the least influence on the compressive strength of concrete. The addition of preabsorbed water to the SAP can delay early cement hydration, increase the later cement hydration rate and final hydration degree, and improve the concrete strength. Preabsorbed water mixed with an SAP can effectively improve the shrinkage of concrete, and the shrinkage reduction effect is more obvious than that from the dry addition of the SAP; the early cracking risk of concrete without an SAP is high, and it will crack before day 28. The addition of an SAP can strengthen the microstructure of concrete and improve its density and crack resistance, effectively avoiding concrete cracking. It is recommended that the water-absorbent resin be incorporated in a preabsorbent manner, and the SAP preabsorbent ratio is equal to the maximum water storage rate of the SAP.

Design of concrete mix ratio and the influence of high water absorption resin and water reducer on strength and working performance

The performance of concrete and water cement ratio, water ratio and unit water consumption has a close relationship, concrete mix ratio design is actually to determine the proportion between the three, correctly determine the proportion relationship, can make concrete meet the design requirements. This paper systematically studies the working performance of concrete with different strength grades, and then compares the experimental results with the four concrete strength grades designed. High water absorption resin process increases the tightness of the slurry, to improve the working characteristics of cement, and then improve the durability of cement function. The influence of the high absorption resin curing agent and water reducing agent on different concrete strength and working performance is studied. The test data between high water absorption resin and absorbent are used to form the change curve of various strength grades, the interaction mechanism between high water absorbent resin and absorbent is analyzed, and puts forward an important scientific basis for the study of cement mix ratio.

Desert soilization: Let scientific principles and facts speak

Desert soilization: Let scientific principles and facts speak

Influence of stone powder content in machine-made sand on mortar concrete

The paper mainly studies that Influence of stone powder content in machine-made sand on mortar concrete. By changing the amount of stone powder in the machine-made sand, the ratio of cement to water and sand to grout, the change in the tensile value of the steel bar in concrete can be found. After a lot of test data to prove that the content of stone powder is 6%, the mortar ratio is 1: 2.5, the water-cement ratio is 0.40, the content of water-absorbent resin is 0.20, and the performance of the C40 concrete is good.

Synthesis, Characterization, and Performance Evaluation of Starch-Based Degradable Temporary Plugging Agent for Environmentally Friendly Drilling Fluid

Abstract Reservoir protection in well drilling and well completion is one of the most significant challenges that have been connected with the quality of the temporary plugging zone and the recovery value of the reservoir permeability when the foreign water invaded into the reservoir copied with the temporary plugging agents. The regular temporary plugging agents are linked with high demand for the matching rate about the pore throat of formation, effect of a single, and poor environmental performance, etc. which markedly impact the operational efficiency. This work reports the synthesis and characteristic of starch-based degradable water-absorbent resin to protect the layer during drilling. Both degradable and excellent SDTA through introducing the nanometre calcium carbonate composites which used as the rigid core were synthesized, characterized, and revalued with standard methods. After purification, there were some groups including the carboxylic acid group, amide group, methyl group, and S=O which reflected the successful synthesis of the monomers. The composites displayed remarkable salt resistance and calcium resistance with 5% and 0.5% as well as thermal stability of 130°C and degradation rate of 50%, respectively. Results also demonstrated that SDTA composites could make the mud cake structure more compact and exhibit self-adaptive to the formation. The SEM images of mud cake treated SDTA revealed that the mechanism could be base on the collaborative action of the structure compact and holes plugging to form an impressive filter cake which could effectively avert the water molecules invasion into the reservoir. Hence, SDTA composites could be a suitable material as a degradable temporary plugging agent for well drilling and completion.

Research into the super-absorbent polymers on agricultural water

Super-absorbent polymers (SAPs) are a family of functional polymer material, with a high water absorption function. It absorbs water hundreds to thousands of times heavier than itself and has excellent water retention performance. Once the water absorption expands into a hydrogel, it is difficult to separate the water even under pressure. This article describes the water absorption and retention capacity of polymer water-absorbent resin, a compound that can solve the problem of water shortages in agriculture, which is very important for the development of modern agriculture.

Lost Circulation Mechanical Model and It’s Application in Permian Igneous Rocks in Shunbei Oilfield

The Shunbei Oilfield is a major discovery of Sinopec in the ultra-deep marine carbonate rock field, and it will become the main battlefield for Sinopec to increase reserves and production. At present, the exploration and development of the Shunbei Oilfield is mainly concentrated on the No. 1 and No. 5 fault zones in the Shunbei area. Due to the complex geological structure, there are a series of drilling technical problems in drilling. Lost circulation will not only lose drilling fluid, produce non-productive time and affect drilling safety, but also limit drilling speed, which is one of the most headaches and difficult problems in drilling. To this end, scholars at home and abroad have carried out a lot of research and exploration, and developed a series of leak-proof and plug-in devices such as non-penetrant, elastic graphite, Form-A-block, fiber cement, water-absorbing resin, thermosetting resin, gel and chemical consolidation. Materials, and formed a variety of supporting process technologies. Granular, fibrous, and sheet composite bridging materials are most commonly used on the site, but ordinary bridging materials are resistant to temperature differences, easily carbonized at high temperatures, and the width of underground cracks needs to be clear when plugging, non-penetrants prevent Lost circulation of microfracture formations. It has poor leak-proof effect on large cracks, because of its low strength, expansion materials such as water-absorbent resin are better for plugging, but the pressure-bearing effect is poor, foreign Form-A-block and Chinese DTR are equivalent High water loss materials have good adaptability to cracks, but the pressure is generally low, fiber plugging methods such as fiber cement and thermosetting resin are complicated in process, high in risk and high in cost, gel plugging technology has good adaptability to plugging, but withstands temperature differences If it is not combined with other materials, it is easy to leak again in the later period due to the decrease in gel strength, chemical consolidation plugging technology has a high success rate in plugging, but the plugging construction time is relatively long. In summary, although great progress has been made in leak prevention and plugging technology at home and abroad, there is less research on igneous rocks, and it cannot meet the needs for leak prevention and plugging in igneous rock formations. Therefore, it is necessary to analyze the second Shunbei Oilfield in depth. Lost circulation characteristics of igneous rocks in the Mesozoic and the difficult points of preventing Lost circulation and plugging. Develop effective materials for preventing and plugging Lost circulation to improve the effect of preventing and plugging.

PAA-AMPS/HA/MMT吸水树脂的吸水性能及吸水动力学研究

PAA-AMPS/HA/MMT吸水树脂的吸水性能及吸水动力学研究

Preparation and application of solid-state upconversion materials based on sodium polyacrylate.

By loading a microemulsion containing both sensitizer and emitter into porous sodium polyacrylate (PAAS), a water-absorbent resin (WAR) upconversion (UC) material was fabricated for photocatalysis applications. This WAR UC material showed a highly efficient UC process in the ambient environment owing to its liquid/solid encapsulation structure. In the application measurement, the UC emission from WAR UC materials can excite the catalyst Pt/WO3 to produce hydroxyl radicals, yielding 7-hydroxycoumarin by reacting with coumarin. In another case, since the band gap of ZnCdS matches the energy of UC emission, hole–electron pairs can be obtained under the UC irradiation and capture electrons from rhodamine B, leading to the degradation of rhodamine B. The maximum of the photocatalysis efficiency can be up to 97%. This work solves the oxygen quenching problem by preparing a triplet–triplet annihilation upconversion (TTA-UC) O/W microemulsion and loading it into PAAS WAR, and opens a new avenue to solid-state devices for TTA-UC. The applications of photocatalytic synthesis and photocatalytic degradation lay a foundation for future practical applications for TTA-UC materials.

反相悬浮聚合法制备AA-AMPS/HA/MMT复合吸水树脂及其性能的研究

反相悬浮聚合法制备AA-AMPS/HA/MMT复合吸水树脂及其性能的研究

The preparation and performance test of a new type of water-absorbent resin dust suppressant with cation

In this paper, the cationic monomer was grafted into the dust suppressant molecule innovatively. The dust particles were adsorbed through net capture function, and the dust suppression efficiency was improved by charge interaction for dust particles’ electronegative. This experiment adopted the starch, acrylic acid and methacryloyloxyethyl trimethyl ammonium chloride (DMC) as raw materials, with potassium persulfate as initiator and glycerol as the crosslinking agent, synthesizing a new type of water-absorbent resin dust suppressant with cation (later called CNDS). After structure characterization and performance test, the results showed that the cationic monomer were successfully grafted and the CNDS had good functions of keeping moisture, wind-resistant, compressive resistance and anti-erosion. The viscosity of CNDS solution (2%) is 24.7 cP, which can bond and adsorb the dust particles in the air effectively. According to economic cost accounting, spraying CNDS only costs 0.46 yuan per square meter. Hence, there is a great prospect of promotion and application due to its low price.

Hydrophilic modification of polytetrafluoroethylene flat membranes coated by acrylic acid water-absorbent resin

Hydrophilic modification of polytetrafluoroethylene flat membranes coated by acrylic acid water-absorbent resin