How Should Montmorillonite Be Rationally Modified? Organic Modification, Inorganic Modification, and Application-Oriented Selection and Validation

Introduction

Montmorillonite has fundamental properties such as water absorption and swelling, adsorption, cation exchange, and layered barrier effects. However, in practical applications, unmodified montmorillonite is not always the most suitable choice.

For applications such as adsorption of cationic pollutants in aqueous systems, thickening and suspension, or anti-seepage sealing, unmodified montmorillonite or sodium-modified montmorillonite may already perform well. However, if the goal is to adsorb hydrophobic organic pollutants, or to incorporate montmorillonite into organic systems such as polymers, rubber, or oil-based drilling fluids, unmodified montmorillonite often suffers from insufficient compatibility, poor dispersion, and weak interfacial interactions.

The key to effective montmorillonite modification is to match its interlayer structure, surface properties, and functional sites with the target application.

1. Why Is Unmodified Montmorillonite Not Always Sufficient?

The performance of unmodified montmorillonite mainly originates from its layered structure, surface charge, and exchangeable interlayer cations. It has advantages in aqueous systems, ion exchange, water absorption and swelling, thickening, and suspension. However, it also has limitations in certain applications.

1.1 Common Limitations of Unmodified Montmorillonite

Application target	Possible limitations of unmodified montmorillonite
Adsorption of hydrophobic organic pollutants	The surface is relatively hydrophilic and has insufficient affinity for nonpolar or weakly polar organic substances
Addition to polymer materials	Poor compatibility with nonpolar resins, rubber, and similar systems; prone to agglomeration
Use in oil-based systems	Insufficient dispersion and rheology control in oil phases
Use in photocatalytic or antibacterial materials	Lacks effective photocatalytic or antibacterial active sites
Use as a magnetic separation adsorbent	Unmodified montmorillonite cannot be rapidly recovered using an external magnetic field
Use in high-performance composites	Interlayer spacing, dispersion state, and interfacial bonding strength may be insufficient
Use for drug or active-ingredient sustained release	Molecular charge, molecular size, release medium, and material safety require further consideration

2. Before Modification: Should You Use Raw Clay, Sodium-Modified Clay, Organic Modification, or Inorganic Modification?

Before designing an experiment, it is necessary to determine whether unmodified montmorillonite can already meet the target requirements.

2.1 Four Questions to Answer Before Modification

Question	Key consideration
What is the target substance?	Is it a cation, anion, hydrophobic organic compound, macromolecule, drug, or polymer?
What is the use environment?	Is it an aqueous phase, oil phase, resin, rubber, soil, saline water, real wastewater, or release medium?
What property needs to be improved?	Adsorption capacity, dispersion, compatibility, barrier performance, catalytic activity, magnetic recovery, or sustained-release performance?
How can the effectiveness of modification be demonstrated?	Can it be jointly verified through structural characterization and performance testing?

2.2 Preliminary Selection Approach

Target scenario	Preferred material or treatment method	Basis for evaluation
Adsorption of cationic pollutants in aqueous systems	Raw clay, purified clay, sodium-modified clay, or inorganic-modified clay	Focus on cation exchange capacity, pH, and surface complexation
Thickening, suspension, and gel formation	Sodium montmorillonite or sodium modification	Focus on swelling behavior, dispersion, and rheological properties
Anti-seepage, sealing, and water retention	Sodium montmorillonite or formulation compounding	Focus on swelling volume, permeability, and stability
Adsorption of hydrophobic organic pollutants	Organically modified montmorillonite	Focus on hydrophobic interactions and modifier stability
Polymer, rubber, and coating composites	Organically modified or coupling-agent-modified montmorillonite	Focus on interfacial compatibility and dispersion state
Oil-based drilling fluids	Organophilic montmorillonite	Focus on oil-phase dispersion and rheological control
Photocatalysis, antibacterial applications, and magnetic separation	Inorganic-loaded or inorganic-composite montmorillonite	Focus on functional components and cycling stability
Drug or active-ingredient sustained release	Purification, intercalation, or mild surface modification	Focus on safety, loading capacity, and release behavior

Summary of selection principles:

① For ionic problems in aqueous systems, prioritize exchange capacity and surface complexation.

② For organic-system problems, prioritize surface compatibility and dispersion.

③ For functional requirements such as catalysis, magnetism, antibacterial activity, and flame retardancy, prioritize the introduction of new functional components.

3. Organic Modification: Solving Compatibility Problems in Organic Systems

Unmodified montmorillonite is usually relatively hydrophilic, and its interlayer cations are mostly inorganic cations such as Na⁺, Ca²⁺, and Mg²⁺. This structure is favorable for hydration, swelling, and ion exchange, but it is not conducive to stable dispersion in oil phases, nonpolar polymers, or hydrophobic organic systems.

The core function of organic modification is to regulate the interlayer environment and surface properties of montmorillonite through organic ions, organic molecules, or polymers, making it more suitable for organic systems.

Common routes for organic modification of montmorillonite include organic ion exchange, surface adsorption, and organic grafting. Common modifiers include cationic, anionic, zwitterionic, nonionic, and polymeric organic compounds. Among them, organic cation exchange is a typical route; anionic, nonionic, zwitterionic, or polymeric modifiers often also involve mechanisms such as surface adsorption, hydrogen bonding, hydrophobic interactions, co-intercalation, complexation, or grafting. These mechanisms should be confirmed through XRD, FTIR, TGA, and desorption/leaching stability tests.

3.1 What Problems Does Organic Modification Mainly Solve?

Problem	Role of organic modification
Poor compatibility with polymers	Regulates surface hydrophilicity/hydrophobicity and improves interfacial bonding
Poor dispersion in oil phases	Enhances affinity for organic phases
Weak adsorption of hydrophobic pollutants	Strengthens hydrophobic interactions
Insufficient interlayer spacing	Organic chain segments entering the interlayer can expand the interlayer spacing
Easy agglomeration in composite materials	Improves platelet exfoliation and dispersion conditions

4. Common Organic Modification Routes and Selection Approaches

4.1 Organic Cation Exchange

Organic cation exchange is one of the most common organic modification methods. Its basic process is as follows:

① The original inorganic cations such as Na⁺ and Ca²⁺ in the montmorillonite interlayer are replaced by organic cations.

② Organic chain segments enter the interlayer space.

③ The interlayer spacing increases.

④ The surface changes from strongly hydrophilic to more organophilic.

Common organic cations include quaternary ammonium salts, imidazolium salts, and pyridinium salts. Among them, long-chain alkyl quaternary ammonium salts are commonly used to prepare organophilic montmorillonite.

Modification result	Effect on application
Increased interlayer spacing	Facilitates the entry of polymer chains into the interlayer
Enhanced surface lipophilicity	Promotes dispersion in oil phases and nonpolar polymers
Introduction of organic chain segments	Can enhance adsorption of hydrophobic organic substances
Change in interlayer environment	Can regulate adsorption selectivity and rheological behavior

The amount of organic cation used is not necessarily better when higher. Too little may result in insufficient modification; too much may cause excessive organic adsorption, pore blockage, reduced thermal stability, or environmental safety risks.

4.2 Surface Adsorption and Grafting Modification

Some organic molecules do not necessarily enter the interlayer strictly through ion exchange. They may also adsorb onto the surface or interlayer of montmorillonite through electrostatic interactions, hydrogen bonding, hydrophobic interactions, or van der Waals forces. Surface adsorption modification is suitable for regulating:

① Surface wettability;

② Dispersion stability;

③ Affinity for specific pollutants or active molecules;

④ Compatibility with coatings, resins, or slurry systems.

Silane coupling agents are commonly used for grafting modification. Through hydrolysis and condensation, silane coupling agents can interact with hydroxyl groups at the edges of montmorillonite or with surface active sites, while providing organic functional groups on the outer side.

Functional group type	Suitable application direction
Amino group	Epoxy resins, polyurethanes, adsorbent materials
Epoxy group	Resin composites, coatings
Vinyl group	Unsaturated resins, free-radical polymerization systems
Methacryloxy group	Acrylic resins, UV-curable systems
Mercapto group	Metal-ion adsorption, specialized interfacial bonding

4.3 Polymer Intercalation or In-Situ Polymerization

Polymer intercalation refers to the entry of polymer chains into the montmorillonite interlayer, thereby expanding the interlayer spacing. In-situ polymerization means that monomers first enter the montmorillonite interlayer or the vicinity of clay platelets, followed by polymerization to form a composite structure. In polymer composites, common structures include:

Structure type	Characteristics
Micro-filled type	Montmorillonite agglomeration is obvious; it mainly functions as an ordinary filler
Intercalated type	Polymer chains enter the interlayer and the interlayer spacing increases
Exfoliated type	Montmorillonite platelets are relatively well dispersed in the polymer
Mixed type	Intercalation, exfoliation, and local agglomeration coexist

Generally, intercalated or exfoliated structures are more favorable for enhancement, barrier performance, and flame retardancy. In actual materials, however, mixed structures often occur, so the overall composite effect must be evaluated comprehensively.

4.4 Selection Table for Organic Modifiers

Application target	Modification focus	Possible modification direction
Nonpolar polymers, such as polyethylene and polypropylene	Improve lipophilicity and interlayer spacing	Long-chain alkyl quaternary ammonium salts, organic intercalation
Polar resins, such as epoxy resins and polyurethanes	Enhance interfacial interactions	Modifiers containing amino, epoxy, or hydroxyl groups
Rubber	Improve dispersion and interfacial bonding	Organic ammonium salts, silane coupling agents
Oil-based drilling fluids	Improve oil-phase dispersion and rheological control	Organophilic montmorillonite
Adsorption of hydrophobic organic pollutants	Enhance affinity for hydrophobic organic phases	Long-chain organic cations, functionalized organic modifiers
Drug or active-molecule loading	Control interactions and release process	Low-toxicity, verifiable modification systems compatible with molecular charge

To determine whether organic modification is effective, it is not enough to look only at whether the interlayer spacing has increased. It is also necessary to determine whether the material truly improves dispersion, interfacial bonding, and final performance in the target system.

5. Inorganic Modification: Introducing New Functional Sites

Organic modification mainly solves compatibility and interfacial bonding problems. Inorganic modification is more often used to introduce new functional sites or change pore structure, surface acidity, magnetism, photocatalytic activity, antibacterial performance, and thermal stability. After inorganic modification, montmorillonite is no longer only an adsorption or thickening material; it can also be used in catalysis, photocatalysis, magnetic recovery, antibacterial applications, flame retardancy, and multi-pollutant removal.

5.1 What Problems Does Inorganic Modification Mainly Solve?

Target problem	Role of inorganic modification
Insufficient adsorption sites	Introduces metal oxides, hydroxyl sites, or composite adsorption sites
Insufficient catalytic or photocatalytic activity	Loads active components such as TiO₂ and ZnO
Difficulty in separation after use	Introduces magnetic components such as Fe₃O₄
Insufficient thermal stability	Improves structural stability through pillaring or inorganic compositing
Limited action against multiple types of pollutants	Composites with layered double hydroxides, carbon materials, and other components
Insufficient flame-retardant or thermal-conductive performance	Introduces inorganic flame-retardant components, carbon materials, or two-dimensional composite components

Different inorganic components can change the pore structure, surface charge, cation exchange capacity, and dispersion state of montmorillonite. Some properties may improve, while others may decrease.

6. Common Inorganic Modification Routes and Applicable Directions

6.1 Acid Activation

Acid activation usually involves treating montmorillonite with acids such as hydrochloric acid or sulfuric acid, causing interlayer cations and some octahedral cations to be leached out. This changes the pore structure, specific surface area, surface acidity, and cation exchange capacity.

Possible change caused by acid activation	Effect on performance
Partial cations are leached out	Forms more pores or amorphous silica phases
Specific surface area or pore volume may increase under appropriate acid activation	Beneficial for some adsorption and catalytic processes
Surface acidity changes	Beneficial for decolorization or acid-catalyzed applications
Cation exchange capacity decreases	May weaken some cation-exchange adsorption processes
Layered structure is damaged	Excessive acid treatment may cause structural destruction

Studies have shown that appropriate acid activation can usually significantly change the physicochemical properties of montmorillonite, such as increasing specific surface area or pore volume while decreasing cation exchange capacity (CEC). However, the effect is influenced by the acid type, concentration, temperature, treatment time, and composition of the original clay. Excessive acid treatment may damage the layered structure. Acid activation is more suitable for decolorization, catalyst supports, adsorption of some organic substances, and pore-structure regulation. For heavy-metal cation adsorption that mainly depends on CEC, acid activation should not be assumed to be necessarily better.

6.2 Metal Oxide Loading

Loading inorganic oxides such as TiO₂, ZnO, Fe₃O₄, MnO₂, and Al₂O₃ onto montmorillonite can introduce new functions.

Loaded component	Possible function introduced
TiO₂	Photocatalytic degradation, organic pollutant treatment
ZnO	Photocatalysis, antibacterial activity
Fe₃O₄	Magnetic separation, magnetic recovery
MnO₂	Redox reactions, synergistic adsorption
Al₂O₃, Fe₂O₃	Surface hydroxyl sites, adsorption or catalytic functions

TiO₂/montmorillonite composites are commonly used in photocatalysis research. Relevant studies have shown that the structure and photocatalytic activity of TiO₂–montmorillonite composites are affected by TiO₂ loading amount, preparation pH, reaction temperature, and reaction time.

Fe₃O₄/montmorillonite composites are commonly used in adsorption systems requiring magnetic recovery. The main role of the magnetic component is to improve solid–liquid separation, but it may also shield some adsorption sites. Therefore, magnetic response and adsorption capacity need to be balanced.

6.3 Inorganic Pillaring and Two-Dimensional Material Composites

Inorganic pillaring involves introducing inorganic polynuclear hydroxy metal cations or metal oxide precursors into the montmorillonite interlayer. After treatment, relatively stable pillar-like structures are formed. The usual purpose is to expand the interlayer space, improve thermal stability, and introduce inorganic sites that can participate in adsorption or catalysis. Common pillaring components include aluminum pillaring, zirconium pillaring, titanium pillaring, iron pillaring, and aluminum–iron composite pillaring.

In addition, montmorillonite can be composited with layered double hydroxides (LDH), graphene (GR), graphene oxide (GO), biochar, and other materials. Relevant reviews have summarized the preparation and application of montmorillonite composites with LDH, graphene, and other two-dimensional materials, including pollutant adsorption, antibacterial applications, thermally conductive films, and flame retardancy.

7. How Can Successful Modification Be Demonstrated?

Whether modification is successful cannot be judged only by color change, sedimentation behavior, or a single improvement in performance. A more reliable approach is to prove it jointly through structural characterization and performance testing.

7.1 Common Characterization Methods and Their Functions

Question to be verified	Recommended characterization method	Information provided
Has the interlayer spacing changed?	X-ray diffraction (XRD)	Basal spacing, intercalation status
Have organic functional groups been introduced?	Fourier transform infrared spectroscopy (FTIR)	Changes in functional groups, adsorption or grafting information
What is the organic modification amount and thermal stability?	Thermogravimetric analysis (TGA)	Mass loss, thermal decomposition range, organic content
Have specific surface area and pore structure changed?	Brunauer–Emmett–Teller specific surface area analysis (BET)	Specific surface area, pore size, pore volume
Has surface electrical property changed?	Zeta potential analysis	Surface charge and dispersion stability
What are the particle morphology and agglomeration state?	Scanning electron microscopy (SEM)	Particle morphology, agglomeration state
What is the platelet dispersion state?	Transmission electron microscopy (TEM)	Intercalation, exfoliation, and nanoscale dispersion state
What are the elemental composition and loading status?	X-ray photoelectron spectroscopy (XPS), energy-dispersive spectroscopy (EDS)	Elemental valence state, surface composition, loaded components
Has wettability changed?	Contact angle testing	Hydrophilicity or hydrophobicity
Have rheological properties changed?	Rheological testing	Viscosity, thixotropy, yield stress

7.2 Validation Focus for Different Modification Targets

Modification target	Key validation
Organic intercalation	XRD, FTIR, TGA
Improved surface lipophilicity	Contact angle, dispersion test, stability in the target system
Enhanced polymer composite performance	XRD, TEM, mechanical properties, thermal properties, barrier properties
Acid activation	BET, CEC, XRD, adsorption or catalytic performance
Metal oxide loading	XRD, XPS, EDS, TEM, target catalytic or adsorption test
Magnetic composite	Magnetic response, recovery rate, adsorption capacity
Drug or active-ingredient loading	Loading capacity, release profile, XRD, FTIR, safety evaluation

8. Selection Approaches for Typical Applications

Montmorillonite modification should start from the specific application. Different applications have different core limitations, and therefore require different modification methods.

8.1 Application Selection Table

Application target	Preferred material or modification direction	Key validation	Notes
Heavy-metal adsorption in aqueous systems	Raw clay, sodium-modified clay, inorganic-modified clay	pH influence, adsorption isotherms, regeneration experiments	Set up adsorbent-free blanks and pH blanks to avoid misidentifying metal precipitation as adsorption
Adsorption of hydrophobic organic pollutants	Organically modified montmorillonite	Contact angle, adsorption capacity, modifier stability	Pay attention to modifier release and secondary pollution
Polymer nanocomposites	Organically modified or coupling-agent-modified montmorillonite	XRD, TEM, mechanical properties, thermal properties	Platelet dispersion is more important than simply increasing the addition amount
Oil-based drilling fluids	Organophilic montmorillonite	Oil-phase dispersion, viscosity, thixotropy	The modifier must be compatible with the oil-phase system and temperature conditions
Photocatalytic pollutant treatment	TiO₂, ZnO, and other inorganic composites	Photocatalytic efficiency, cycling stability	Pay attention to active-component agglomeration and light-response range
Magnetic recovery adsorption	Fe₃O₄/montmorillonite composites	Magnetic response, recovery rate, adsorption capacity	Excessive magnetic component may reduce adsorption sites
Flame-retardant or barrier composites	Organically modified or inorganic-composite montmorillonite	Heat release, barrier performance, dispersion state	Processing performance and mechanical properties must both be considered
Drug or active-ingredient sustained release	Purified montmorillonite, intercalation, or mild surface modification	Loading capacity, release profile, safety evaluation	Industrial-grade materials cannot be used directly for pharmaceutical research

The performance improvement of polymer/layered silicate nanocomposites is usually related to intercalation, exfoliation, interfacial bonding, and platelet dispersion state. Early research on nylon 6/clay nanocomposites showed that a small amount of layered silicate can significantly affect material properties, which promoted the development of polymer/clay nanocomposites.

The direction of drug or active-ingredient sustained release requires particular caution. Existing studies have shown that drug molecules can intercalate into the montmorillonite interlayer and exhibit in-vitro release behavior, but such studies do not mean that ordinary montmorillonite can be directly used in pharmaceutical formulations. Applications related to pharmaceuticals, food, feed, or cosmetics must consider material grade, purity, impurities, residues, and safety.

9. Why Does Modified Montmorillonite Still Fail to Perform Well?

In montmorillonite modification experiments, common problems do not necessarily arise from the preparation steps themselves. They often result from unclear objectives, insufficient characterization, or evaluation conditions that are too idealized.

9.1 Common Reasons for Failure

Failure mode	Possible cause
Interlayer spacing increases, but performance does not improve	The modifier has entered the interlayer, but dispersion in the target system remains poor
Adsorption capacity improves, but performance in real water samples is poor	Competitive ions, natural organic matter, or pH effects have not been considered
Mechanical properties of the polymer decrease	Montmorillonite agglomeration, excessive addition amount, or insufficient interfacial bonding
Thermal stability decreases after organic modification	The organic modifier has a relatively low thermal decomposition temperature
Heavy-metal adsorption decreases after acid activation	CEC decreases and cation exchange capacity is weakened
Photocatalytic performance is unsatisfactory	Active components agglomerate, loading amount is unsuitable, or light response is insufficient
Adsorption capacity decreases after magnetic compositing	Magnetic components shield adsorption sites or reduce specific surface area
Sustained-release performance is unstable	The loading method is unstable and the release medium has a significant influence

9.2 Necessary Control Groups

Control group	Function
Unmodified montmorillonite	Determines whether modification truly brings improvement
Sodium-modified or purified montmorillonite	Distinguishes the effects of purification, sodium modification, and functional modification
Modifier alone	Excludes the adsorption or reaction contribution of the modifier itself
Inorganic component alone	Determines whether synergy exists after compositing
Blank system	Excludes natural sedimentation, volatilization, photolysis, or precipitation effects
Reuse/cycling group	Evaluates material stability and regeneration capability

10. Basic Workflow for Modification Experiments

Montmorillonite modification can be designed according to the sequence of “target–material–modification–characterization–performance.”

10.1 Experimental Design Steps

Step	Core task
1. Clarify the application target	Adsorption, thickening, reinforcement, barrier performance, catalysis, magnetic separation, or sustained release
2. Analyze the target system	Aqueous phase, oil phase, resin, rubber, real wastewater, or release medium
3. Select the base material	Raw clay, purified clay, sodium-modified clay, or a specific grade of montmorillonite
4. Determine the modification route	Organic modification, inorganic modification, or composite modification
5. Set up control groups	Raw clay, modifier, inorganic component, blank system, etc.
6. Perform structural characterization	XRD, FTIR, TGA, BET, SEM, TEM, etc.
7. Perform performance testing	Adsorption, rheology, mechanical properties, barrier performance, catalysis, or release experiments
8. Evaluate stability	Cyclic use, leaching, thermal stability, long-term storage
9. Assess application value	Cost, reproducibility, scale-up difficulty, and safety

10.2 Simplified Decision Table

Target	Preferred route	Key validation
Improve aqueous dispersion and swelling	Sodium modification	Swelling volume, viscosity, particle size, rheology
Adsorb cationic pollutants	Raw clay, sodium-modified clay, inorganic modification	CEC, pH, isotherms, precipitation blanks, regeneration
Adsorb hydrophobic organic substances	Organic modification	Contact angle, adsorption capacity, stability
Add to polymers	Organic modification or grafting modification	XRD, TEM, mechanical properties, thermal properties
Photocatalytic degradation	TiO₂, ZnO, and other inorganic loading	Photocatalytic efficiency, cycling stability
Magnetic recovery adsorption	Fe₃O₄ composite	Magnetic response, recovery rate, adsorption capacity
Drug or active-ingredient sustained release	Intercalation or mild surface modification	Loading capacity, release profile, safety

11. Product Recommendations for Montmorillonite Modification Research and Experimental Selection

Note: The following products are mainly intended for scientific research, material preparation, or methodological evaluation. For applications involving pharmaceuticals, food, feed, cosmetics, environmental release, or large-scale water treatment, the product grade, COA/SDS, impurities and residues, regulatory applicability, and leaching safety should be separately confirmed. Research-grade or industrial-grade materials should not be directly regarded as equivalent to pharmaceutical-grade, food-grade, or engineering-deployment materials. Specific specifications, inventory status, and documentation should be subject to the Aladdin official website, product pages, COA, and SDS.

Table 1. Products Related to Basic Montmorillonite Materials, Pretreatment, Acid Activation, and Organobentonite Rheology Materials

Category	CAS No.	Aladdin Catalog No.	Name	Specification or Purity	Product Features and Applications
Acid-activated montmorillonite material	1318-93-0	M758183	Montmorillonite K-10	Powder	Used for research on acid-activated montmorillonite adsorption, decolorization, catalyst supports, surface acidity, and pore structure
Organobentonite rheology material	1302-78-9	B102861	Bentonite	Bentone SD-2, suitable for medium- to high-polarity solvents	Used for research on dispersion in organic systems, coating rheology, suspension stability, and resin composites
Sodium-modification reagent	497-19-8	S141342	Sodium carbonate, anhydrous	≥99.5%	Used for sodium modification of calcium-based montmorillonite, interlayer cation regulation, swelling behavior, and dispersion research
Ionic-strength adjustment reagent	7647-14-5	S433743	Sodium chloride	Anhydrous, ACS, ≥99%	Used for ion exchange, salinity-effect studies, adsorption controls, and dispersion-stability research
Alkali treatment and pH adjustment reagent	1310-73-2	S111501	Sodium hydroxide	ACS, ≥97%	Used for montmorillonite alkali treatment, pH adjustment, surface charge control, and adsorption-condition regulation
Acid-activation reagent	7647-01-0	H399545	Hydrochloric acid (controlled precursor chemical)	ACS, ≥37%	Used for montmorillonite acid activation, cation leaching, pore-structure regulation, and surface-acidity research
Acid-activation reagent	7664-93-9	S399872	Sulfuric acid (controlled precursor chemical)	ACS, 95–98%	Used for montmorillonite acid activation, decolorization adsorption, catalyst supports, and specific surface area regulation

Table 2. Products Related to Organic Modifiers and Silane Coupling Agents

Category	CAS No.	Aladdin Catalog No.	Name	Specification or Purity	Product Features and Applications
Organic cationic modifier	57-09-0	C274355	Hexadecyltrimethylammonium bromide (CTAB)	High grade	Used for organophilic montmorillonite preparation, interlayer intercalation, hydrophobic modification, and organic pollutant adsorption research
Organic cationic modifier	112-02-7	H105309	Hexadecyltrimethylammonium chloride (CTAC)	≥97%	Used for organic intercalation of montmorillonite, surface hydrophilicity/hydrophobicity regulation, and polymer composite research
Organic cationic modifier	112-03-8	S105314	Octadecyltrimethylammonium chloride (STAC)	≥98%	Used for long-chain quaternary ammonium salt modification of montmorillonite, oil-phase dispersion, and hydrophobic adsorption research
Organic cationic modifier	107-64-2	D113403	Dimethyldioctadecylammonium chloride (D1821)	≥97%	Used for preparation of dual-long-chain quaternary ammonium organophilic montmorillonite, resin compatibility studies, and interlayer structure regulation
Organic cationic modifier	56-37-1	B108417	Benzyltriethylammonium chloride (TEBAC)	≥98%	Used for organic cation exchange of montmorillonite, interlayer environment regulation, and phase-transfer-related modification research
Organic cationic modifier	1643-19-2	T103374	Tetrabutylammonium bromide	Ion-pair chromatography grade, ≥99%	Used for quaternary ammonium salt intercalation, ion-exchange controls, and screening of organic modification conditions
Silane coupling agent	919-30-2	A107147	3-Aminopropyltriethoxysilane (APTES)	≥99%	Used for preparation of aminated montmorillonite, resin interfacial bonding, metal-ion adsorption, and surface grafting research
Silane coupling agent	2530-83-8	G107576	3-Glycidyloxypropyltrimethoxysilane	≥97%	Used for epoxy-functionalized montmorillonite, epoxy resin composites, coating interfaces, and grafting reaction research
Silane coupling agent	2768-02-7	V162969	Vinyltrimethoxysilane	≥98% (GC)	Used for vinyl-functionalized montmorillonite, free-radical polymerization systems, and interfacial modification of composites
Silane coupling agent	2530-85-0	S111153	3-(Methacryloyloxy)propyltrimethoxysilane	≥97%, contains 100 ppm BHT stabilizer	Used for montmorillonite grafting in acrylic resin systems, UV-curable coatings, and interfacial compatibility research
Silane coupling agent	4420-74-0	M100619	(3-Mercaptopropyl)trimethoxysilane	≥95%	Used for preparation of mercapto-functionalized montmorillonite, metal-ion binding, rubber composites, and surface functionalization research

Table 3. Products Related to Inorganic Loading, Magnetic Composites, and Two-Dimensional Composites

Category	CAS No.	Aladdin Catalog No.	Name	Specification or Purity	Product Features and Applications
Photocatalytic loading material	13463-67-7	T431947	Titanium dioxide (IV)	Premium grade, ≥99%	Used for titanium dioxide/montmorillonite composites, photocatalytic degradation, pollutant treatment, and active-component loading research
Photocatalytic and antibacterial loading material	1314-13-2	Z111836	Zinc oxide	AR, ≥99%	Used for zinc oxide/montmorillonite composites, photocatalysis, antibacterial applications, and inorganic functional-component loading research
Magnetic composite material	1317-61-9	I104312	Iron(II,III) oxide	≥99%	Used for preparation of magnetic montmorillonite, magnetic recovery adsorption, solid–liquid separation, and cyclic-use research
Redox functional material	1313-13-9	M101141	Manganese dioxide	GR, ≥90%	Used for manganese dioxide/montmorillonite composites, redox adsorption, and multi-pollutant treatment research
Metal oxide loading material	1344-28-1	A420214	Aluminum oxide	≥99% metals basis	Used for aluminum oxide-loaded montmorillonite, surface hydroxyl sites, adsorption, and catalyst-support research
Metal oxide loading material	1309-37-1	F108317	Iron(III) oxide	AR, ≥99%	Used for iron oxide/montmorillonite composites, surface-complexation adsorption, and inorganic functionalization research
Layered double hydroxide composite material	11097-59-9	H302201	Synthetic hydrotalcite	—	Used for montmorillonite/hydrotalcite composites, anionic pollutant adsorption, flame retardancy, and composite adsorption research
Carbon-based two-dimensional composite material	1034343-98-0	G302113	High-purity graphene	≥99%	Used for graphene/montmorillonite composites, thermal conduction, reinforcement, barrier performance, and functional coating research
Carbon-based two-dimensional composite material	2640657-49-2	G476611	Graphene oxide	15–20 layers, 4–10% edge oxidation	Used for graphene oxide/montmorillonite composites, adsorption, membrane materials, and interfacial functionalization research

Table 4. Products Related to Adsorption Performance Evaluation and Drug-Loading Models

Category	CAS No.	Aladdin Catalog No.	Name	Specification or Purity	Product Features and Applications
Heavy-metal adsorption simulation reagent	10099-74-8	L431226	Lead(II) nitrate (controlled explosive precursor)	European Pharmacopoeia (Ph. Eur.), suitable for analysis, ACS, premium grade	Used for montmorillonite lead-ion adsorption, pH-effect studies, cation exchange, and simulated water-treatment experiments
Heavy-metal adsorption simulation reagent	10022-68-1	C118495	Cadmium nitrate tetrahydrate	PrimorTrace™, ≥99.999% metals basis	Used for cadmium-ion adsorption, trace metal analysis, competitive adsorption, and environmental remediation research
Heavy-metal adsorption simulation reagent	13478-00-7	N108888	Nickel nitrate hexahydrate (controlled explosive precursor)	PrimorTrace™, ≥99.999% metals basis	Used for nickel-ion adsorption, metal-ion competition systems, and adsorption-capacity evaluation research
Heavy-metal adsorption simulation reagent	7758-99-8	C112396	Copper(II) sulfate pentahydrate	AR, ≥99%	Used for copper-ion adsorption, surface complexation, ion exchange, and adsorption kinetics research
Drug-loading model compound	26921-17-5	T129917	(S)-Timolol maleate	≥97%	Used for montmorillonite drug intercalation, loading capacity, in-vitro release, and sustained-release behavior research

Note: The above are representative Aladdin products. More product specifications can be searched on the Aladdin official website using the product name, CAS number, or catalog number.

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