▶ Core Product Features:

1. Dual Water-Stopping Mechanism: After curing, the adhesive forms an elastic sealant. In the dry state, it adheres tightly to the concrete/metal substrate due to its high adhesion, sealing gaps and forming an initial seal. Upon contact with water, the internal expansion components undergo a chemical reaction, expanding uniformly and compressing the gap walls, filling the tiny voids between the sealant and the gap, achieving "water-stopping with water." There is no swelling or detachment after expansion, ensuring a long-lasting water-stopping effect.

2. High Elasticity and Deformation Resistance: After curing, the Shore A hardness is 20-45 degrees, with an elongation at break ≥400% and an elastic recovery rate ≥80%. It can adapt to dynamic deformations (displacement ±20%) in concrete structures caused by temperature, settlement, and earthquakes, maintaining sealing performance over a long period without cracking or delamination.

3. Strong Adhesion and Wide Compatibility: It has a bonding strength ≥1.0MPa with commonly used engineering substrates such as concrete, cement mortar, steel, and rubber (waterstop strips/belts). There are no voids at the interface, requiring no additional primer (a special primer can be used for some rough substrates). The adhesion is reliable and does not delaminate.

4. High adaptability: Available in self-leveling and non-sagging types. The self-leveling type is suitable for horizontal gaps (such as expansion joints in floor slabs), automatically leveling and filling the gap to ensure a smooth surface. The non-sagging type is suitable for vertical/diagonal gaps (such as expansion joints in exterior walls and tunnel sidewalls), preventing dripping and sagging after application, resulting in a beautiful finish.

5. Excellent weather and media resistance: Does not crack at -30℃, does not soften or drip at 80℃; resistant to weak acids, weak alkalis, groundwater, rainwater, etc., does not age or yellow with long-term outdoor/underground use, with a service life of ≥15 years.

6. High ease of application: Single-component type is moisture-curing, ready to use after opening, no on-site mixing required; two-component type allows for adjustable curing speed; the paste form can be applied mechanically with a caulking gun, suitable for confined spaces and complex gaps, with no obvious application dead zones.

7. Environmentally friendly and solvent-free: The mainstream products are solvent-free, with no odor or release of harmful gases during construction, and no release of harmful substances after curing. They meet the environmental protection requirements of building engineering and have good compatibility with concrete substrates.

▶ Product Specifications and Models

1. Core Classification (Based on Construction Characteristics/Components)

2. Model classification (based on the final expansion ratio at room temperature, consistent with the standard for waterstop strips, facilitating model selection)

3. Standard Packaging

Single Component: 600ml flexible packaging (for glue guns only).

▶  Core Application Scenarios

Waterstop adhesive is the core material for **"sealing" in engineering waterproofing**. It can be used alone or in conjunction with waterstop strips and waterstop belts to form a multi-layered waterproofing system. It is suitable for sealing expansion joints, construction joints, and post-cast strips in various engineering projects such as buildings, municipal works, water conservancy, and rail transit. It is especially suitable for dynamic expansion joints, wide gaps, and irregular gaps that are difficult to fit with waterstop strips. Typical application areas:

1. Underground Engineering: Sealing expansion joints in basement floors/exterior walls/roofs; sealing dynamic expansion joints in subway tunnels/stations; sealing expansion joints/settlement joints in underground pipe galleries; used in conjunction with embedded waterstop belts and prefabricated waterstop strips;

2. Water Conservancy Engineering: Structural expansion joints in reservoirs, dams, and sluices; expansion joints in water tanks and sewage treatment plant structures; sealing gaps at pump station inlets and outlets;

3. Municipal Engineering: Expansion joints in integrated pipe galleries and urban bridge abutments; sealing rainwater/ 

4. Industrial and Civil Buildings: Sealing of structural joints in sewage pumping stations and underground pipe interfaces;

5. Industrial and Civil Buildings: Sealing of joints in civil defense projects, expansion joints in the underground parts of large shopping malls/office buildings, caulking of roof expansion joints, and sealing of post-cast strip joints;

6. Supporting Auxiliary Products: Sealing and reinforcement of waterstop overlaps and waterstop joints, and repair of concrete cracks (cracks ≥ 2mm wide).

Not suitable for: Cracks that are constantly immersed in strong acids, strong alkalis, or strong organic solvents (such as gasoline and acetone); micro-cracks with a crack width < 2mm (for micro-cracks, grouting adhesive is preferred); and high-temperature open flame environments.

▶  Core Advantages of the Product

Comparison with Waterstop Strips (PN/PZ/Self-adhesive Type)

1. Wider Adaptability: Can fill wide gaps, irregular gaps, and dynamic expansion joints, solving the waterproofing problem of gaps where waterstop strips are difficult to fit;

2. Strong Integral Sealing: After the paste-like adhesive cures, it forms a continuous elastic seal without overlapping gaps, avoiding the risk of leakage at the joints of waterstop strips;

3. Superior Resistance to Dynamic Deformation: High elastic recovery rate, able to adapt to long-term structural expansion, contraction, and settlement deformation, maintaining sealing performance for a long time;

4. Flexible Construction: Can be applied manually with a caulking gun or mechanically, adapting to narrow spaces and complex gaps, eliminating construction dead ends.

▶  Key Advantages:

1. Ready to Use/Simple Mixing: Single-component formula requires no on-site mixing, resulting in high construction efficiency; two-component formula offers adjustable curing speed to suit different project timelines.

2. Reliable Adhesion: High adhesion to various substrates, requiring no additional primer (optional in some scenarios), with no gaps at the interface, preventing leakage at the source.

3. Strong Waterproofing and Durability: Solvent-free formula, no bubbles or pinholes after curing, excellent weather resistance and media resistance, service life ≥15 years, matching the lifespan of the engineering structure.

4. Strong Compatibility: Can be used with pre-made waterstops, self-adhesive waterstops, embedded waterstops, and back-adhesive waterstops to form a double/triple waterproofing system of "waterstop strip/belt + waterstop adhesive," enhancing the waterproofing level of the project.

▶  V. Simplified Construction Points (Mainly Single-Component Polyurethane Waterstop Adhesive)

1. Substrate Preparation (Core and Crucial, Determining Bonding Effectiveness)

Clean the gap and both sides (within a 50mm radius) of laitance, dust, oil, and standing water, ensuring the substrate surface is flat, dry, and firm; smooth uneven areas with an angle grinder, and level cracks with repair mortar; if the substrate has a high moisture content, it needs to be dried (moisture content ≤8%).

2. Joint Filling Preparation

Foam rods (backing strips) can be pre-embedded in the gap to control the thickness of the waterstop adhesive (the adhesive thickness should be 1/2-2/3 of the gap width, and ≥10mm), avoiding excessively thick/thin adhesive layers that affect elasticity and water-stopping effect;

Apply masking tape to non-construction surfaces to prevent contamination of surrounding concrete during adhesive application and ensure a neat finish.

3. Adhesive Application

Single-component type: Load the flexible packaging into the caulking gun, cut the nozzle (the nozzle diameter is slightly smaller than the gap width), and apply the adhesive continuously and evenly along the gap, ensuring the adhesive fills the gap completely, without air bubbles or gaps.

Two-component type: Mix components A and B evenly according to the product ratio (mechanical mixing is preferred), and apply the adhesive using a caulking gun/applied glue machine. The mixed adhesive must be used within its shelf life.

Overlap joints: The overlap length of the adhesive application should be ≥50mm, and it must be pressed firmly and tightly. For vertical gaps, apply the adhesive from bottom to top to avoid air bubbles.

4. Curing and Maintenance

After application, cure at room temperature (5-35℃) in a well-ventilated environment. Single-component adhesives cure by relying on moisture in the air; surface drying time ≤24 hours, complete curing time 3-7 days (ambient temperature/humidity affects curing speed);

During curing, avoid rain, water immersion, and external impact to prevent deformation and damage to the adhesive layer;

After complete curing, remove the masking tape and clean any surrounding contamination.

5. Matching Application

When used with waterstop strips/belts, first install and secure the waterstop strips/belts, then apply adhesive to both sides of the gap, ensuring a tight bond between the adhesive layer and the waterstop strip/belt to form a complete waterproof system.

▶ Quality and Testing Standards

The entire product manufacturing process adheres to the national standards JC/T 2037 (water-swellable sealant) and GB/T 16776 (silicone sealant). Each batch undergoes comprehensive quality testing before leaving the factory. Key testing indicators (water-swellable polyurethane):

1. Appearance: Uniform paste, free of particles, lumps, and layering; uniform color (standard black, gray/white available upon request);

2. Application Performance: Self-leveling type exhibits satisfactory self-leveling properties; non-sagging type shows no dripping or sludge when applied vertically;

3. Physical and Mechanical Properties: Shore A hardness 20-45 degrees, elongation at break ≥400%, elastic recovery ≥80%, and bond strength to concrete ≥1.0MPa;

4. Water Swelling Performance: Expansion ratio meets standards for the corresponding model; no swelling or peeling after immersion in water; bond strength retention rate after expansion ≥80%;

5. Weather Resistance/Media Resistance: No cracking at -30℃ low-temperature flexing; no softening or dripping at 80℃ high-temperature heating; no significant performance degradation after water immersion (168h);

6. Environmental Performance: Volatile organic compound (VOC) content ≤100g/L; no release of harmful gases such as benzene and formaldehyde.

▶ VII. Storage and Transportation Requirements

1. Storage: Store in a dry, ventilated, and cool warehouse at a temperature controlled between 5-25℃. Avoid high temperatures (≥40℃), direct sunlight, rain, and moisture. Single-component types must be stored in sealed containers to prevent moisture from entering and causing premature curing. Two-component types (A/B components) must be stored separately to avoid mixing.

2. Transportation: Avoid squeezing, collisions, and inversion during transportation to prevent damage to the packaging. Transport as non-hazardous goods, avoiding mixing with strong acids, strong alkalis, and organic solvents.

3. Shelf Life: Single-component types have a shelf life of 12 months under sealed storage conditions. Two-component types (A/B components) have a shelf life of 18 months when stored separately in sealed containers. Performance testing is required after the shelf life; only those components that pass the test can be used.

4. Application Environment: The application temperature should be controlled between 5-35℃. Avoid application in rain, snow, strong winds, low temperatures (<5℃), or high temperatures (>35℃). In special environments, insulation/cooling measures are required.

VIII. Principles for Using Waterstop Strips in Conjunction Waterstop adhesive and various water-swellable waterstop strips (putty type/prefabricated type/self-adhesive type) are complementary, not substitutes. In engineering projects, a dual waterproofing system of waterstop strips (strips) + waterstop adhesive is commonly used. The core principles are:

1. Narrow joints (≤20mm), regular joints, and static joints: Self-adhesive/prefabricated waterstop strips are preferred due to their ease of application and cost-effectiveness.

2. Wide joints (≥20mm), irregular joints, and dynamic expansion joints: Waterstop adhesive is preferred, or a combination of "waterstop strip + waterstop adhesive" is used. The waterstop strip fills the core of the joint, and the waterstop adhesive seals both sides.

3. High-level waterproofing projects (subway/water conservancy/civil defense): A triple waterproofing system of "embedded waterstop strip + prefabricated waterstop strip + waterstop adhesive" is used to comprehensively seal against potential leaks.

Water-swellable sealant (mainstream water-swellable polyurethane type) production process and core raw materials: Water-swellable sealants are mainly single-component polyurethane type, accounting for more than 90% of the market. The core process is to synthesize polyurethane prepolymer + compound functional components + high-speed dispersion/kneading + grinding and filtration + filling to form a paste-like elastic sealing material, which has both elastic sealing and water-swellable properties. The entire production process requires precise control of reaction temperature, component ratio and dispersion uniformity. The following is a detailed description of the raw material composition and standardized production process of polyurethane water-swellable sealant (including the core differences between single and two components).

▶ Core Raw Materials and Functional Proportions

Raw materials are categorized by functional system. The core difference in single-component formulations lies in the curing system. Water-swellable systems and tackifying/reinforcing systems are generally applicable. All raw materials must meet the requirements of being solvent-free, low-VOC, and compatible with concrete. The proportions of each system and core raw materials in a typical formulation are as follows:

1. Base Material System (Core skeleton, 30%-40%)

Determines the elasticity, adhesion, and weather resistance of the waterproofing adhesive, and is the basis for the synthesis of polyurethane prepolymers.

Polyether polyols: Mainstream uses polyether diols (PPG-2000/3000) and polyether triols (POP-3600). The soft segment structure gives the product high elasticity, low-temperature flexibility, and tensile properties. Low-unsaturation polyethers are preferred to improve the stability of the prepolymer.

Polyester polyols: Added in some high-end formulations to enhance oil resistance and media resistance, suitable for water conservancy and chemical engineering.

Isocyanates: Mainly MDI (diphenylmethane diisocyanate) (44V20, MDI-50), with small amounts used. 1. TDI (Toluene Diisocyanate): Synthesized with polyether polyols to form polyurethane prepolymers, determining the crosslinking density and bond strength of the product.

2. Water-Swelling System (Core Function, 15%-25%)

To achieve "water-swelling and water-stopping," the expansion ratio must be controllable, with no swelling or detachment, and good compatibility with the polyurethane matrix.

Hydrophilic Polyurethane Prepolymer: Self-made/Purchased, reacts with water to form urea-formaldehyde, achieving volume expansion. It is the main expansion source (accounting for over 70% of the expansion system), with mild expansion and tight bonding to the matrix, without exudation;

Superabsorbent Polymer (SAP): Sodium acrylate-acrylamide copolymer, assisting expansion, requires surface hydrophobic modification (to prevent water swelling and detachment), addition ≤5% (excessive addition will reduce elasticity and adhesion);

Sodium Bentonite: A natural inorganic expansion component, regulating slow-swelling properties, reducing the initial expansion rate, preventing excessive expansion from cracking the concrete, and simultaneously improving thixotropy to prevent vertical sizing flow.

3. Curing System (Core Difference Between Single/Two Components, 5%-10%) 

This determines the curing method, surface drying time, and full curing time of the sealant. It must be compatible with water-swellable systems.

Single Component (Moisture Curing, Mainstream) Relies on both airborne moisture and water in the gaps for dual curing, eliminating the need for on-site mixing.

Latent Curing Agents: MOCA (dichlorodiphenylamine methane), polyetheramine D230, added in small amounts to adjust the curing speed;

Catalysts: Organotin (dibutyltin dilaurate), amine catalysts (triethylenediamine), controlling the reaction rate between the prepolymer and water. Surface drying time is controlled at 4-8 hours to avoid excessively fast curing causing bubbles, or excessively slow curing affecting construction.

Implementation Standards

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