Introduction to Polyamidoamine

Polyamidoamine belongs to aliphatic ambient-temperature epoxy curing agents, synthesized via amidation reaction between fatty acids and polyamines. Its molecular structure contains both amide groups and active amino groups. Different from high-molecular-weight traditional polyamide curing agents, polyamidoamine features lower inherent viscosity and excellent compatibility with epoxy resin. Benefiting from flexible long carbon chains in its molecular structure, cured systems with polyamidoamine deliver balanced adhesion, moisture resistance and reasonable pot life. It has become a widely adopted ambient cure system for flooring, industrial coatings and electrical encapsulation applications.

Product Overview of Highfar HF-3175

HF-3175 is a low-viscosity polyamidoamine epoxy curing agent independently developed by Highfar. It serves as a direct equivalent to mainstream imported grade, customers can replace imported raw materials directly without extensive formula modification to optimize supply chain costs.

Key Technical Specifications

Appearance: Light brown transparent liquid

Color: ≤8 (Gardner)

Viscosity @ 25°C: 200–600 mPa.s

Total amine value: 320–380 mg KOH/g

Active hydrogen equivalent: 75 g/eq

Recommended dosage: 40 phr (based on epoxy resin, EEW=190)

Gel Time (100g mixture @ 25°C): 30–40 min

Core Advantages of HF-3175

• Low viscosity for favorable workability

With viscosity ranging from 200 to 600 mPa.s at 25°C, HF-3175 offers moderate mixed viscosity after blending with epoxy resin. It facilitates brushing and self-leveling construction. Less solvent dilution is required, supporting the formulation of high-solid coatings and lower VOC emissions.

• Outstanding substrate adhesion

Polar groups inside the molecule effectively wet concrete, metal and other substrates. The cured coating achieves strong adhesion and greatly reduces risks of peeling or delamination, making it ideal for concrete surface coating.

• Excellent moisture resistance

Compared with ordinary aliphatic amine curing agents, HF-3175 delivers better resistance to moisture and blooming. It tolerates construction under relatively humid conditions and maintains stable water resistance after curing.

•Balanced pot life and curing speed

The gel time reaches 30–40 minutes at 25°C under standard mixing ratio, offering sufficient time for construction. A dense cross-linked structure forms after full ambient cure, balancing construction efficiency and end-product performance.

•Drop-in replacement for imported counterparts

Comparable performance with established overseas polyamidoamine grades enables easy raw material localization, helping coating and encapsulation manufacturers cut procurement costs.

Typical Applications

•Concrete flooring and surface protective coatings Suitable for epoxy primer, intermediate coats and concrete sealer. Reliable adhesion on porous cementitious substrates.

• Electrical encapsulation & insulating coatings Used for insulation encapsulation and protective coatings of small electronic components. Low viscosity ensures thorough wetting of gaps inside components to form stable insulation protection.

• General two-component epoxy protective coatings & adhesives Can be extended to light-duty anti-corrosion topcoats and general epoxy bonding systems.

Conclusion

HF-3175 low-viscosity polyamidoamine curing agent integrates easy handling, strong adhesion and superior moisture resistance. It is a cost-effective alternative to imported curing agents for flooring coatings and electrical encapsulation sectors. Highfar continuously devotes to R&D of epoxy curing agents. We provide stable bulk supply and professional formulation support. Samples and technical consultation are available upon request.