Get Sample

Documents

WANHUA Isocyanates

Last update on Nov 28, 2025

WANHUA Aliphatic Diisocyanates for adhesives: Ensuring purity with low monomer content

Expertly formulated aliphatic diisocyanates enhance the bonding strength, durability, and chemical resistance of adhesives, ensuring exceptional performance in demanding industrial applications.

ABOUT WANHUA – Advancing Chemistry, Transforming Lives

Wanhua Chemical Group headquartered in Yantai, ShandongChina, stands as a global leader in the production of isocyanates, pivotal components in polyurethane chemistry. The company boasts a comprehensive portfolio encompassing both aromatic and aliphatic isocyanates, catering to diverse applications across coatings, adhesives, elastomers, and foams.

Key Isocyanate Products (monomers and derivatives)

MDI (Methylene Diphenyl Diisocyanate)
TDI (Toluene Diisocyanate)
IPDI (Isophorone Diisocyanate)
HDI (Hexamethylene Diisocyanate)

Wanhua continues to innovate in the adhesives sector with products that offer excellent weather resistance, color retention, and mechanical properties, suitable for automotive OEM and refinishing coatings, as well as industrial applications. Demonstrating a commitment to sustainability, several of Wanhua's products, including MDI, TDI, and IPDI, have obtained ISCC PLUS certification. This certification underscores the company's dedication to reducing carbon footprints and promoting sustainable practices in the chemical industry.

Wanhua Chemical Group's extensive range of isocyanates, coupled with its focus on innovation and sustainability, solidifies its position as a key player in the global polyurethane industry.

Introduction to Isocyanates:

Isocyanates are reactive compounds widely used in polyurethane systems, where they act as curing agents by reacting with polyols. This reaction forms durable, high-performance films with excellent mechanical strength, chemical resistance, and weatherability. The isocyanate-based products are used for automotive, industrial, tile and grout systems, and are valued for their fast curing, strong adhesion, and gloss retention. However, due to health risks like respiratory sensitization, careful handling is essential. While safer and more sustainable alternatives are emerging, isocyanates remain key for better adhesive features.

Aliphatic Diisocyanates – What are these?

Aliphatic Diisocyanates are highly reactive chemicals used predominantly in the production of polyurethane products. They are crucial components in creating polymers and are particularly valuable in the adhesive industry because they react with various substances, including alcohols (to form urethanes) and water (to form foams), offering tailored properties for specific applications.

Quick Read

Isocyanates: Compounds with at least one isocyanate group (-NCO), serving as the fundamental building blocks for polyurethane materials.
Polyisocyanates: Polymers composed of multiple isocyanate groups, offering enhanced cross-linking in polyurethane products through their multiple reactive sites.

Blocked isocyanates:

Blocked isocyanates are a versatile solution in the formulation of heat-activated adhesives. In adhesive systems where controlled reactivity and extended shelf life are critical, blocked isocyanates offer a reliable way to delay curing until the desired thermal activation stage. The isocyanate group is temporarily “blocked” with a protecting agent, preventing premature crosslinking during storage or application. Once heat is applied—typically during the bonding or lamination process—the blocking agent is released, enabling the isocyanate to react with polyols or active hydrogen compounds. This results in strong, durable polyurethane networks with excellent mechanical strength, chemical resistance, and adhesion to a variety of substrates. Blocked isocyanates are especially useful in high-performance industrial adhesives, such as those used in automotive assembly, industrial, tile and grout systems.

WANNATE^® Aliphatic Diisocyanates: Tailored Solutions for Diverse Applications

Wanhua Chemical's WANNATE^® series utilizes the unique reactivity of isocyanates to engineer adhesives that enhance performance in several critical applications.

Key Properties - WANNATE^® GRADES

Bonding & Durability

Isocyanates create durable linkages for robust, long-lasting bonds

Versatility

Effective on various substrates, suitable for automotive, construction, and more

Curing Speed

Fast curing, ideal for quick assembly with adjustable rates for tailored applications

Chemical Resistance

Provides resilient bonds against chemicals, oils, and solvents

Temperature Resistance

Maintains effectiveness across a range of temperatures

Formaldehyde Free

Reduced health risks and increased safety with low VOC formulations

Flexibility

Flexibility post-curing that is essential for dynamic applications

WANNATE^® Grades – Key Benefits

Better mechanical strength

Better viscosity

Resistance to chemicals

Weathering resistant

Low monomer content

HIGHLIGHTS – Chemical Properties

NCO Content: Each grade has a specified range for NCO content, which is essential for determining their reactivity and suitability for different applications.

Purity: High purity levels (generally above 99.5%), ensuring high-quality end products.

Low Monomer Content: Specified limits on monomer content like HDI or IPDI, enhancing stability and safety.

PRACTICAL APPLICATIONS

Aliphatic Diisocyanates (ADI) in Batteries

Wanhua Chemical's WANNATE^® series, specifically formulated with Aliphatic Diisocyanates (ADI), specifically formulated with Aliphatic Diisocyanates (ADI), provides advanced solutions for battery bonding in electric vehicles and energy storage systems. ADI-based polyurethane (PU) structural adhesives offer unique advantages optimized for high-performance battery applications.

Advantages of Aliphatic Diisocyanates (ADI) in Batteries

Extended Pot Life

ADI formulations offer the longest working time among competing chemistries, facilitating complex assembly processes without compromising speed or efficiency

Enhanced Thermal Conductivity

The lower viscosity inherent to ADI allows for higher additive loading, which enhances the thermal management of battery packs, crucial for maintaining optimal operating temperatures and efficiency

Customizable Flexibility

ADI-based adhesives can be tailored to meet specific flexibility requirements, providing a robust solution that accommodates thermal expansion and mechanical stresses within battery modules

Advantages of PU Structural Adhesives

Compared to other adhesive technologies, PU structural adhesives synthesized from WANNATE® ADI exhibit superior characteristics essential for battery bonding:

Superior Adhesion and Cohesion: PU adhesives provide better bonding strength than silicone-based adhesives, ensuring a secure and durable attachment of battery components.
Improved Weatherability: Offering significant improvements over epoxy adhesives, PU adhesives excel in various environmental conditions, resisting weathering, moisture, and thermal cycling.
Flexibility and Low Hardness: The inherent flexibility and lower hardness of PU adhesives facilitate easy positioning and adjustment during assembly processes, enhancing handling operations and impact resistance.
Versatile Mechanical Properties: These adhesives are engineered to meet the diverse demands of battery applications, providing a balance of strength, flexibility, and durability that is critical for the dynamic stresses encountered in mobile and stationary battery systems.

The graphs display the performance characteristics of different WANNATE^® Diisocyanates: HMDI, IPDI, HT-100, HT-300and HT-600, showcasing variations in pot life, mechanical properties (shear and tensile strength, elongation at break), and Shore A hardness, highlighting their diverse applications based on durability and flexibility.

EXPLORE WANNATE^® ADI GRADES

Advantages of PU Structural Adhesives

WANNATE SPECIALTY ALIPHATIC DIISOCYANATES FOR POLYASPARTIC GROUT AND SEALER

In grout and sealer applications, adhesives play a critical role in ensuring long-term performance under moisture, mechanical, and chemical stress. These systems require precise formulation to deliver strong adhesion, fast curing, and resistance to water ingress and staining.

Polyaspartic resin technologies, when combined with Wanhua’s aliphatic diisocyanates WANNATE^® HT-600 and WANNATE^® HT-300, offer excellent mechanical strength, UV durability, and hydrolytic stability, making them ideal for both interior and exterior construction environments.

KEY CHARACTERISTICS

Low VOC Emissions

Solvent-free, 100% solids formulation for environmentally responsible applications.

Excellent Weatherability

Preserves both appearance and performance over long-term exposure.

Hardness & Flexibility

Delivers outstanding scratch and abrasion resistance under stress and impact.

Strong Adhesion

Promotes robust bonding to substrates for enhanced durability.

Adjustable Working Time

Easily tailored to meet varying application needs.

Superior Chemical Resistance

Shields surfaces from aggressive chemicals and pollutants.

Mechanical performance comparison - Cured polyaspartic resins

Graph 2(a). Medium cure polyaspartic resins exhibit significantly higher pull-off adhesion with diisocyanates compared to slow cure variants.
Graph 2(b). WANNATE^® HT-600 delivers the highest tensile strength across both slow and medium cure polyaspartic resins.

Hydrolytic stability of cured polyaspartic resin

Mechanical Property	Medium Cure Resin with WANNATE^® HT-600			Medium Cure Resin with WANNATE^® HT-300
Mechanical Property	Control	Soak	Soak and Dry	Control	Soak	Soak and Dry
Maximum Tensile Strength (MPa)	41.7	39.5	41.6	39.9	35.6	39.7
Tensile Modulus (GPa)	1.837	1.782	1.744	1.589	1.389	1.605

Test conditions: Wanhua internal method

WANNATE^® HT-600 demonstrates slightly better retention of tensile strength and modulus after hydrolytic aging compared to WANNATE^® HT-300, indicating superior hydrolytic stability.

Wanhua-polyaspartic grout formulations can show very high pull-off adhesion and/or strain performance, indicating excellent formulation tailorability using various grades of Wannate aliphatic diisocyanates.

Formulation Recommendations

Property	Increase	Decrease
Set Time/ Working Time	HT-300	HT-600
Maximum Tensile Strength & Young's Modulus	HT-600	HT-790B, HT-300
Adhesion	HT-300	HT-790B, HT-600
Chemical Resistance (Immersion)	HT-300	HT-600
Hydrolytic Stability	HT-600	HT-300
Strain Resistance	HT-790B, HT-600	HT-300

The table provides formulation guidance for adjusting key performance properties in polyaspartic systems using different WANNATE^® aliphatic polyisocyanate grades.

Products

See All Products

WANNATE® HT-400

WANNATE® HT-400 by Wanhua Chemical is an aliphatic polyisocyanate based on hexamethylene diisocyanate (HDI). It can be used as a reactive thinner or a hardener. It is sensitive to moisture. <ul style="padding-left: 40px;"><li>In two-component polyurethane system, it is widely used combining WANNATE® HT-100, HT-600 and IT-170B with hydroxy polyacrylate as ideal reactant.</li> <li> It can be used as single binder or other polyisocyanate mixture.</li> <li> It can be thinned with esters, ketones and aromatic hydrocarbons such as ethyl acetate, butyl acetate, methoxypropylacetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, xylene, solvent naphtha 100.</li> <li> It shows good compatibility with aliphatic polyisocyanates, polyester polyols, aromatic polyisocyanates and polyacrylates. </li> <li>WANNATE® HT-400 is recommended for automotive applications.</li> <li> It can be stored for at least 6 months at temperatures between 0 and 30°C.</li>

Support available
Original documents

See the Product

WANNATE® HT-100

WANNATE® HT-100 by Wanhua Chemical is a low viscosity, solvent-free aliphatic polyisocyanate based on hexamethylene diisocyanate (HDI). It offers high weather resistance, very good gloss retention, high chemical resistance and outstanding mechanical properties. </li> <ul style="padding-left: 40px;"><li> It can be used as a hardener and is sensitive to moisture. </li> <li> It can be thinned with esters, ketones and aromatic hydrocarbons such as ethyl acetate, butyl acetate, methoxypropylacetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, xylene, solvent naphtha 100 and mixtures. </li> <li> WANNATE® HT-100 is compatible with aliphatic polyisocyanates, polyester polyols, aromatic polyisocyanates and polyacrylates. </li> <li> Recommended for adhesive applications. </li> <li> It has a shelf life of 15 months. </li></ul>

Sustainable option
Support available
Original documents

See the Product

WANNATE® HMDI

WANNATE® HMDI by Wanhua Chemical is a low-viscosity cycloaliphatic diisocyanate with characteristic odor. It is a raw material for polyurethanes and has good mechanical strength. It is abrasion- and hydrolysis resistant and retains gloss and physical properties upon weathering. It is able to form optically clear polyurethanes when combined with suitable polyol coreactants. Recommended for adhesives and sealant applications. WANNATE® HMDI has a shelf life of atleast 9 months when stored at temperture between 0 and 30 °C.