Superabsorbent Polymer Research Articles

Multi-inspired bump-liked medical protective clothing for effectively profuse perspiration management

Janus medical protective clothing (MPC) with asymmetric wetting properties can enhance the comfort of healthcare workers by transporting sweat from the skin to exterior surfaces. However, these textiles fail to promptly remove heavy sweat (e.g., several liters), resulting in soaked fabrics and reduced comfort. Herein, inspired by superabsorbent polymers (SAPs) and lotus leaves, we propose a bump-liked MPC (BPC) for profuse perspiration management. The fabrics can enable unidirectional sweat transport through the inner Janus fabric layer and sustained absorption of large amounts of sweat by the median layer of SAPs. The bump-liked structure can store SAPs and adapt them to swelling. An external polydimethylsiloxane (PDMS)-coated layer can effectively block water, blood, and ethanol from penetrating the skin (synthetic blood contact angle, 118°; anti-blood penetration resistance, 4.8 kPa), thereby ensuring excellent protective properties. More importantly, BPC possesses an unrivalled sweat removal rate of 5.9 ml cm−2 min−1, which is three orders of magnitude higher than the human sweat rate during high-intensity exercise. This work addresses the dual challenge of profuse perspiration management and resistance to liquid penetration, which represents a promising direction for improving the thermal-moisture comfort of medical protective clothing.

A novel conceptual design for self-healing of cracked cementitious composites incorporating two bacteria-based capsules

Expanded polystyrene (EPS) is a low-density material prone to float during composite mixing and vibration. Inspired by this, a two-bacteria-capsule system was reported in this study to enhance the self-healing capacity of cracked mortar. Specifically, the BC-A capsule, containing aerobic bacteria, EPS, and superabsorbent polymer (SAP), and the BC-N capsule, containing anaerobic bacteria and SAP, are prepared through granulation using polyethylene glycol. Sulphoaluminate cement and epoxy resin are used to encapsulate the core materials. The BC-A capsules automatically float in the composite preparation process, while the BC-N capsules are distributed in the middle and bottom regions due to extrusion effect. Upon capsule rupture, the two types of bacteria are released in regions favorable for biomineralization, corresponding to the principle that oxygen concentration reduces along the crack depth. The self-healing behaviour was evaluated as well as the healing products were characterized. The results showed that the capsules cracked simultaneously with the composite and the coating effectively avoided premature release of the self-healing materials. Cementitious composites containing double capsules achieved 90 % closure of cracks with initial widths of 50–600 μm. The three-dimensional healing capacity was significantly enhanced, particularly in terms of impermeability and strength recovery ratio. The main healing products in the cracks were calcite and swollen SAP. The swollen SAP provided nucleation sites and enough water for biomineralization in the healing process.

Application of SAP to Improve the Handling Properties of Iron Ore Tailings of High Cohesiveness: Could a Reagent Help the Decommissioning Process of a Dam?

This work aims to evaluate the use of a superabsorbent polymer (SAP) to provide improvements in the handling properties of iron ore tailings (IOT). The material studied came from the magnetic separation reprocessing of the material discarded at the Gelado Dam, located in Serra dos Carajás in the state of Pará, Brazil. While the concentrate presents reasonable handling conditions, the tailings, with 61.5% iron, 15% moisture, and 39% of the mass, have high cohesiveness and adhesiveness due to their fine nature and the climatic conditions of the Amazon rainforest. However, the tailings can still be considered a product as long as the handling and transportation logistics are feasible. Thus, studies with an SAP and IOT were carried out in a bench rotating drum to promote mixing between them, and the main variables studied were the SAP dosage and the required contact time. The improvement in the physical properties of the IOT were evaluated considering the Hausner ratio, Carr index, Jenike’s flow function index, Atterberg limits, and chute angle. The superabsorbent polymer promoted a significant improvement in the state of consistency of the material, and the best performance was obtained with a dosage of 1000 g t−1. As long as a suitable contact condition was promoted, a contact time of 1 min was enough to achieve the expected benefits. After dosing with the superabsorbent polymer, the material’s handling classification changed from ‘cohesive’ to ‘easy flow’, and the chute angle was reduced from 90° to levels below 60°. It was concluded that the application of the superabsorbent polymer has the potential to improve the fluidity of the material discarded in the magnetic concentration operation, allowing it to be handled throughout the production and transportation chain. The SAP appears to be an important additive for the full use of the material present in the dam (100% recovery), with both economic and socio-environmental benefits.

Investigation of functionalized graphene oxide incorporated superabsorbent polymers for enhanced durability, hydration, microstructure and mechanical strength of modified concrete

ABSTRACT This study focuses on enhancing cementitious materials by incorporating silanized graphene oxide (SGO) and superabsorbent polymers (SAPs), aiming to improve their mechanical and durability properties. The primary goal is to evaluate the effects of SGO/SAP composites on the hydration, absorption, shrinkage, and overall performance of concrete. The composites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) to understand their microstructure. Mechanical and durability tests revealed that adding SGO/SAP composites significantly increased the mechanical strength and water absorption capabilities of the concrete. The compressive strength, split tensile strength, and flexural strength of the SGO/SAP-modified concrete were measured at 57 MPa, 4.90 MPa, and 8.25 MPa, respectively. Shrinkage tests demonstrated the composite hydrogel’s excellent water-holding capacity at 0.3 wt.% SGO/SAP, facilitating internal curing in concrete structures. FE-SEM analysis indicated a reduction in microcracks due to the presence of SGO/SAP. The improvements are attributed to the synergistic effects of SGO and SAP, which enhance water retention, dispersion, and interfacial bonding within the cementitious matrix. The microstructural studies confirmed the exceptional stability of the SGO/SAP-modified mix, emphasizing its potential as an additive to improve concrete properties. This research underscores the significant potential of SGO and SAP in advancing the performance of cement-based materials, highlighting their applicability in infrastructure development and construction for creating more durable and high-performing concrete structures.

Co-application of kaolin and superabsorbent polymer mitigate water stress and improves yield and water use efficiency in tomato plant

Water stress is one of the factors that remarkably constrain agricultural productivity in Iran. This experiment aimed to evaluate the effect of Kaolin (KL) and Superabsorbent polymer (SAP) separately or in combination on alleviating harmful effects of water stress on tomato. A factorial experiment was designed with two main factors: irrigation regimes (100, 75 and 50 % of the crop evapotranspiration (ETc)) and drought-alleviating treatments (control, KL, SAP, and KL+SAP) under field condition. Results showed that water deficit (exclusively at 50 % ETc) significantly decreased total fruit yield, water use efficiency (WUE), relative water content (RWC), and chlorophyll content, whereas it increased the rate of osmolyte accumulation, malondialdehyde, and antioxidant enzymes activities. As compared to the other treatments, the interaction of KL+SAP at different irrigation regimes (at 50, 75, and 100 % ETc) raised total fruit yield by 172, 111, and 103 %, respectively. Furthermore, the highest WUE, RWC, and chlorophyll content and conversely the lowest osmolyte accumulation, MDA, and H2O2 content were obtained by KL+SAP treatment at different irrigations. This indicates that co-application of KL and SAP could alleviate the harmful effect of water stress on tomato plant; therefore, it can be used to improve tomato's yield and WUE in areas with drought stress.

Bond and cracking behavior of tailored limestone calcined clay cement-based composites including bicomponent polypropylene fibers with enhanced mechanical interlocking

This study examines the potential of combining tailored binder formulations with engineered polypropylene (PP) fibers to develop a range of Fiber-Reinforced Cementitious (FRC) systems with enhanced ductility and strain-hardening properties, while encompassing sustainability and economic viability. The experimental investigation compares the surface microstructure of novel bicomponent PP fibers, produced using a pilot fiber spinning device, with that of standard PP fibers. Micro-scale single-fiber pull-out tests are conducted to ascertain the extent to which this surface modification contributes to enhanced energy absorption. The effectiveness of these novel fibers at the composite scale is assessed when embedded into two limestone calcined clay cement (LC3) binder systems, in terms of the fresh and hardened properties of the resulting FRLC3, with low cement content (35% of the total binder). The effect of incorporating super absorbent polymer (SAP) on tailoring the internal porosity of the matrix, thereby promoting the potential for stress transfer via multiple crack pathways, is assessed. A Finite Element Method (FEM) analysis, calibrated with the materials and bond laws retrieved experimentally, is conducted to simulate the tensile and cracking behaviour of the optimal material combination investigated in this study, demonstrating a high degree of correlation with the tensile tests.

Synthesis of a chitosan-based superabsorbent polymer and its influence on cement paste

To address the challenge of adaptability between cement-based materials and conventional superabsorbent polymers (sodium polyacrylate, Na-PA), a chitosan-based superabsorbent polymer (CSP) with high salt and alkaline resistance was synthesized, and the optimal synthesis process was determined by a single-factor method. The macroscopic performance and microstructure of CSP and Na-PA were compared, and their influences on cement paste were studied. The results show that CSP exhibits a gradual swelling process during water absorption, which is independent of the solution environment. The poriferous structure of CSP allows it to form a network composed of gel membranes. The introduction of amide group enhances the resistance of CSP to salt and alkaline conditions. The autogenous shrinkage of cement paste is mitigated by CSP, with a superior effect compared to Na-PA. The longer desorption time of CSP allows it to promote cement hydration for a longer period, reducing the loss of compressive strength. The heat release, chemically bound water and hydration products (portlandite and amorphous substances) of CSP pastes are higher than those of Na-PA pastes. The water desorption from CSP fills some middle capillary pores and mesopores, leading to the pores in the hardened cement paste being more concentrated in smaller sizes.

Effect of super absorbent polymers on the self-healing capability of macrocracked ultra-high performance concrete under highly aggressive environments

In this study, the performance of superabsorbent polymers (SAPs) as self-healing agents in macrocracked ultra-high performance concrete (UHPC) was extensively evaluated, with a focus on compressive strength behavior in different aggressive environments. Three UHPC mixtures were designed: a control mixture, a UHPC with 0.3 % sodium polyacrylate (poly(AA)), and a UHPC with 0.3 % polyacrylate-co-acrylamide (poly(AA-co-AM)). Samples with macrocrack widths of 0.3 mm, 0.5 mm, and 1 mm, as well as uncracked samples, were prepared. The samples underwent immersion in deionized water, chloride saltwater, and compound saltwater. The performance of self-healing was evaluated by measuring crack closure rates, recovered compressive strength, and stereomicroscopic inspections. Further, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX) was performed to monitor mineral formation and the healing process. The results indicate that both poly(AA) and poly(AA-co-AM) SAPs significantly enhanced the self-healing capabilities of UHPC, with poly(AA) demonstrating superior performance. Self-healing was more pronounced in samples with cracks width of 0.3 mm, whereas samples with cracks widths of 0.5 mm and 1.0 mm exhibited incomplete and negligible healing, respectively. The healed samples recovered a substantial portion of their compressive strength, regardless of the crack width. However, the presence of chloride and/or sulfate ions was found to impede the self-healing process. As observed from the SEM/EDX results, in addition to CaCO3 and C-S-H gel, undesirable healing products like Friedel’s salt and ettringite were also formed in chloride and compound saltwater environments which significantly affected self-healing durability.

Fermentative production of 3-hydroxypropionic acid by using metabolically engineered Klebsiella pneumoniae strains

3-Hydroxypropionic acid (3-HP) is an industrially important platform chemical for super-absorbent or biodegradable polymers. Its production via biological methods is expected to be more competitive than chemical methods. Klebsiella pneumoniae is the most promising host due to its innate capabilities for 3-HP and vitamin-B12 production, ease of culture, and ease of engineering. In this study, step-by-step metabolic engineering and fermentation technologies were used to enhance the production of 3-HP. K. pneumoniae-derived ydcW gene was overexpressed using a plasmid after screening candidate genes. Major competing pathways encoded by dhaT, yqhD, ldhA, glpK, poxB, and pta-ackA were blocked. Additionally, it was demonstrated that simultaneous reinforcement of two native aldehyde dehydrogenase encoded by the ydcW gene preferring NADPH and the puuC gene preferring NADH, synergistically improved 3-HP production. Additional reinforcement of the acs gene to reduce acetate accumulation resulted in 93.7 g/L of 3-HP with a yield of 0.42 g/g·glycerol over a 72-h fed-batch fermentation. This performance is deemed sufficient for industrial applications.

Self-sealing cementitious materials by utilizing superabsorbent polymers

A current direction in scientific research is the search for technological solutions that provide high reliability for building materials. Incorporating self-sealing agents during the design phase makes concrete more eco-friendly by reducing the maintenance processes and extending concrete's lifespan which leads to reducing the need to produce cement causing a lot of CO2 emissions. As a consequence, this investigation describes an attempt to assess the performance of superabsorbent polymer (SAP) as a self-sealing agent. In the experimental work, two different particle sizes were taken into consideration, SAP1 (425–600μm) and SAP2 (> 600 μm) and for preparing SAP-based concrete and the ratio of SAP was (0.3% wt of cement) with water/ cement (0.4). The regular test was performed for compressive strength at the age of 28 days and the pre-crack phase to generate the initial crack started after 28 days. Two series of sealing periods Cy4th and Cy10th under wet-dry cycles were taken to promote the sealing process. The DZM (Digital Zoom Microscope) system for microscopic analysis was used to detect the self-sealing phenomenon and the width of the sealing on the concrete cracks' surface by using specialist software (image process). The outcomes demonstrated that there was a positive effect of using SAP as a sealing agent, depending on particle size the SAP2 healed the crack up to 0.15mm and the percentage of partially sealing at Cy4th was 64% compared to the other mixes.

Effect of In Situ Polymerization of Super Absorbent Polymers on the Protection of Earthen Heritage Sites in Semi-Arid Regions

As precious cultural heritage, earthen sites are susceptible to various natural factors, leading to diverse forms of degradation. To protect earthen sites, the effects of super absorbent polymers (SAPs) on soil water retention, physical properties, and color compatibility at different concentrations were studied. After applying SAP treatment to an earthen site with different degrees of weathering, we drew the following conclusions. SAP-2 improved soil water retention capacity, increased soil water content, and slowed down the precipitation of soluble salts. At the same time, SAP-2 had the least effect on soil color difference and reduced the development of cracks by filling soil pores and enhancing the cohesion between soil particles, thus giving the earthen sites better weathering resistance. Therefore, the results provide a useful reference for the surface cracking of earthen sites in semi-arid areas and the degradation caused by flaking and block spalling.

Cow Dung-Based Superabsorbent Polymers as Water-Retaining Amendments of Soils

Cow Dung-Based Superabsorbent Polymers as Water-Retaining Amendments of Soils

Controllable heat release of supercooled Erythritol-based phase change materials for long-term thermal energy storage

Transeasonal heat storage in organic phase change materials (PCMs) present a promising solution to the intermittent nature of renewable energy. However, PCMs are prone to spontaneous crystallization during storage, leading to the loss of stored latent heat in low-temperature environments. In this study, we incorporated tetrasodium ethylenediaminetetraacetic acid (EDTA-4Na) and superabsorbent polymer (SAP) to erythritol (ERY), referred to as EES-PCMs, to overcome these challenges and achieve more controllable and stable thermal energy storage. The incorporation of EDTA-4Na and SAP into ERY significantly improves the supercooling stability and phase change enthalpy. The optimal ratio (EES-PCMs-2) of phase change enthalpy reaches an impressive 286.62 J/g, with stable performance maintained for 120 days at room temperature. The EES-PCMs-2 exhibits exceptional thermal cycling stability, retaining its properties even after 100 cycles. A novel air-triggered crystallization method is demonstrated, enabling a temperature increase from room temperature to 48.21 °C in 320 s after being exposed to air for long-term storage. This innovative approach effectively overcomes the limitations of traditional triggering mechanisms, providing a straightforward and efficient method for thermal management. The high thermal storage capacity, stability, and controlled exothermic properties of EES-PCMs position them as promising candidates for applications in seasonal solar thermal energy storage.

Heat transfer mechanism of superabsorbent polymers phase change energy storage cold-formed steel wall under fire

The superabsorbent polymer phase change materials (SAP materials) exhibit exceptional water absorption and retention properties, offering substantial potential for fire protection in steel structures, thereby reducing the need for sheathing boards and fire-retardant coatings, while minimizing energy consumption. Understanding the heat-mass exchange theory of SAP materials is crucial for enhancing their application in the building industry. This study develops a comprehensive theoretical model for heat-mass exchange in cold-formed steel (CFS) walls incorporating SAP materials. An equilibrium phase change model and a simplified thermal radiation model were developed to capture the water loss and dynamic heat exchange processes in SAP materials. These models were integrated into a transient fluid-solid-thermal coupling model using Ansys Fluent and User Defined Functions. In the case study, the newly developed numerical models can accurately predict temperature field changes in CFS walls with SAP materials, demonstrating the heat transfer mechanisms of hot and cold flanges at different temperature rise stages. The developed numerical model was used to investigate the effects of factors such as the moisture content of the SAP material, web depth, and flange width on the fire resistance of the CFS wall. Results indicated that increasing the wall stud height improves fire resistance, while increasing flange width has little effect on hot flange temperature. These findings provide a theoretical foundation and practical guidelines for the application of SAP phase change insulation materials in the building industry, promoting energy reduction and supporting sustainable construction practices.

Phase change hydrogel formed by osmotic pressure for thermal energy storage

The present study investigates the potential of latent heat storage using phase change materials (PCMs) to reduce building energy consumption, addressing the common challenges of PCM leakage and compatibility with construction materials. We introduce a novel phase change hydrogel, created by encapsulating polyethylene glycol (PEG) within a superabsorbent polymer (SAP) network through osmotic pressure. The structural and thermal characteristics of the PEG/SAP composite were analyzed using differential scanning calorimetry (DSC), thermal gravimetric analysis (TG), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and polarizing optical microscopy (POM). Results demonstrated that PEG effectively filled the SAP network, forming a stable composite structure, with PEG as the core and SAP as the supporting matrix. The composite achieved a remarkable PEG mass fraction of 80 %, yielding a melting enthalpy of 129.7 J/g and a peak melting temperature of 51.89 °C. Additionally, PEG/SAP exhibited robust thermal stability up to 300 °C. Notably, when incorporated into cement, surface temperatures of phase change cement decreased by 12 °C compared to conventional Portland cement under constant heating. This approach highlights high latent heat capacity, low production costs, and straightforward fabrication, positioning PEG/SAP as a promising solution for large-scale applications in building energy conservation.

Formulation and characterization of super absorbent copolymer AA, ACN-grafted sodium acrylate for feminine napkin

Absorbency for feminine napkins is a research priority in the recent era, though commercial napkins are available with the same function properties achieved through finishing. One of those methods is coating SAPs, which act as hydrogels. Super absorbent polymers are generally coated in the second- or third-layer of the napkin. The present work deals with the coating of the SAP on the top layer by forming poly (acrylic acid)/sodium acrylate (ACN-g-PAA/SA) and demonstrating its absorption properties. Ultimately, we conducted a comparative analysis of all the SAPs prepared, and demonstrated an absorptive capacity of 104.35 g/g in tap water and 51.28 g/g in saline solution during free swelling. Additionally, under a specific load, it demonstrated 56.48 g/g in tap water and 27.42 g/g in saline solution. Based on the comparative results suggested by the TGA curve, water absorbency, and moisture content, the present work proposes a polymer suitable for coating the feminine napkin.

Prediction and investigation of water repeated absorption and release properties of superabsorbent polymers during the dry-wet cycles in different solutions

Superabsorbent polymers (SAP) with a three-dimensional cross-linked network structure are used in the concrete field due to their good water absorption and water retention properties. The changes of its repeated water absorption and release properties have an important impact on crack healing, but there is still a lack of relevant research. This study mainly uses the tea-bag method to explore the repeated water absorption and release behavior of sodium polyacrylate and polyacrylic acid-acrylamide copolymers in deionized water, cement filtrate, and saturated calcium hydroxide solution. The quantitative analysis of the change in the peak area of the water-absorbing functional group was performed by fourier transform infrared spectroscopy. The morphology and elements of SAP under different dry-wet cycles were analyzed by scanning electron microscope-energy spectrum analysis. The repeated swelling behavior of SAP was predicted using the classical models. The results showed that the repeated water absorption performance of SAP gradually decreased with the increase of the number of wet-dry cycles. The slope of the curve for the second-order equation gradually increases, and the peak area corresponding to the carboxyl functional group also gradually increases. And the rate and amount of water release gradually increase. For sodium polyacrylate, with the increase in the number of wet-dry- cycles, the increase in the content of calcium, magnesium, and aluminum elements is accompanied by a significant decrease in the content of sodium elements. In contrast, the calcium content on the surface of polyacrylic acid-acrylamide copolymer increased, but the sodium content only slightly decreased.

Exploring cement content's impact on self-healing in super absorbent polymer-modified concrete

This study shows the impact of varying cement content while maintaining a constant water-to-cement (w/c) ratio on the performance of self-healing concrete. It also explores the effect of F-type fly ash on the self-healing mechanism of concrete. Self-healing concrete, incorporating super absorbent polymers, offers a viable remedy to diminish the detrimental effects of cracks, enhancing the durability and lifespan of concrete structures. While the w/c ratio is a crucial factor influencing concrete properties, the impact of varying cement content under a constant w/c ratio in self-healing concrete remains understudied. Therefore, this experiment involved preparing 18 different concrete mixtures using three distinct cement contents under three specific w/c ratios. Fly ash was mixed in half of the specimens. Super absorbent polymers are incorporated into all mixtures to facilitate autonomous healing by absorbing and retaining water, which is released upon crack formation. Specimens were pre-cacked using a stress-controlled UTM machine. To evaluate the self-healing mechanism, low water pressure permeability test, water absorption test, and image analysis were conducted at 7, 14, 28, and 56 days. The findings of this study show that a w/c ratio of 0.35 yielded the best performance which indicates a lower w/c shows a higher self-healing performance. Additionally, the specimen containing a higher cement content exhibited enhanced healing capacity compared to other specimens. However, the specimens with fly ash failed to show a satisfactory result on self-healing capacity because the addition of silicon-based fly ash (F type) created an adverse effect on the self-healing mechanism.

Water retention and heat storage characteristics of phase change hydrogel in cooling pavement

Phase change hydrogel (PCH) combines the heat storage characteristics of phase change material with the water retention capacity of hydrogel, showing great potential in cooling pavement applications. This study aims to investigate the water retention and heat storage properties of PCH in cooling pavement, providing new insights for mitigating the urban heat island effect. Based on the principle of osmotic pressure, polyethylene glycol (PEG) solution was actively absorbed by superabsorbent polymers (SAP) to form stable PCH. By infusing the asphalt mixture skeleton with PCH-containing phase change grouting material (PCGM), a temperature-regulating phase change grouting pavement (PCGP) can be obtained. Morphological characterization showed that PCH was uniformly distributed in PCGM and effectively locked PEG during high temperature and water absorption/release processes without leakage. PCH imparted excellent water retention properties to PCGM, with a saturation water absorption rate of 44.1 %, which is 6.2 times higher than the control group, and a water retention rate of 34.31 % after heating at 60 °C for 12 hours. Furthermore, PCGM exhibited considerable heat storage performance, with a melting enthalpy of 15.74 J/g and a crystallization enthalpy of 12.07 J/g. Based on these, PCGP demonstrated outstanding temperature-regulating ability, reducing surface temperatures by 9.3 °C and 11.6 °C under dry and saturated conditions, respectively, compared to control pavement. In conclusion, this study provides a theoretical basis for the development of novel cooling pavement materials and shows great potential for its wide application in urban infrastructure construction.

Additive-assisted macroscopic self-assembly and control of the shape of assemblies based on host–guest interaction

In these decades, considerable attention has focused on supramolecular polymers due to their unique structures and properties. More recently, macroscopic supramolecular polymers have attracted increasing interest from not only biologists but also materials scientists inspired by the sophisticated structures and functions of living organisms. Since the functions of supramolecular polymers are strongly dependent on their shape, control of the shape is an important issue in controlling the functions of supramolecular polymers. However, the control of shape in macroscopic supramolecular assemblies has not yet been sufficiently investigated. Previously, we studied the macroscopic self-assembly behavior of super absorbent polymer (SAP) microparticles modified with β-cyclodextrin (βCD) and adamantane (Ad) residues (βCD(x)-SAP and Ad(y)-SAP microparticles, where x and y are the mol% contents of βCD and Ad residues, respectively). More elongated assemblies were formed at higher y, indicating that the shape of assemblies can be controlled by varying the interaction strength. The noteworthy is that 1-adamantanamine hydrochloride (AdNH3Cl) assisted the formation of assemblies from βCD(x)-SAP and Ad(y)-SAP microparticles, indicating that AdNH3Cl acts as a chemical stimulus for macroscopic assemblies of βCD(x)-SAP and Ad(y)-SAP microparticles. In this study, we have thus studied the assembling behavior of βCD(x)-SAP microparticles with Ad(y)-SAP microparticles and unmodified SAP microparticles assisted by AdNH3Cl, as well as the shape of the resulting macroscopic assemblies. AdNH3Cl assisted the formation of assemblies from βCD(16.2)-SAP and Ad(15.1)-SAP microparticles, in which AdNH3Cl crosslinked the SAP microparticles through the formation of inclusion complexes of βCD residues with the Ad residue and the electrostatic interaction of ammonium and carboxylate residues. Assemblies of βCD(26.7)-SAP and unmodified SAP microparticles were formed at the concentrations of AdNH3Cl ([AdNH3Cl]0) higher than a certain level (ca. 0.05 mM). The aspect ratio (a/b) of assemblies showed a maximum at [AdNH3Cl]0 ~ 0.10 mM, indicating that the chemical stimulus, i.e., addition of AdNH3Cl, controls the shape of assemblies formed from βCD(26.7)-SAP and unmodified SAP microparticles. This study suggests that other stimuli, e.g., heat, pH, light, redox, and force, can be utilized to control the shape of macroscopic assemblies based on supramolecular interactions.