What is NBR foam made of? | ASLONG Guide

What is NBR Foam Made Of? | ASLONG

Professionals in the sound insulation industry often require precise, rapid information about core materials. This article answers the critical question, “What is NBR foam made of?”, clarifying chemical composition, primary uses, and its significance in sound insulation. Key terms like NBR foam, sound insulation materials, and industry standards are discussed to assist designers, installers, and specifiers seeking reliable material insights.

What is NBR Foam Made Of?

NBR foam, also known as nitrile butadiene rubber foam, is widely recognized for its superior acoustic and thermal performance in sound insulation materials. Below, we detail composition, characteristics, and industry applications.

Chemical Composition of NBR Foam

• Main Ingredients:

  • Nitrile Butadiene Rubber (NBR): A synthetic copolymer of acrylonitrile (ACN) and butadiene.
  • Key ratio: ACN content within NBR varies, typically 18-50%, affecting resistance to oils and flexibility (Source: Rubber World Magazine, 2021).
  • Additional compounds: Vulcanizing agents, blowing agents, stabilizers, fillers, and pigments are included to enhance performance.

• Foaming Process:

  • NBR is compounded and blended with chemical blowing agents.
  • During heating, blowing agents release gas, expanding the material into a closed-cell structure for optimal acoustic and thermal insulation.

Key Characteristics Relevant to Sound Insulation

• Closed-Cell Structure

  • Provides excellent sound absorption and noise reduction due to trapped air pockets.
  • Limits moisture and air passage, maintaining consistent performance in humid environments.

• Durability and Chemical Resistance

  • High resistance to oils, fuels, and many chemicals, making it suitable for industrial and automotive settings.

• Temperature Stability

  • Maintains flexibility and performance in temperatures from -40°C to +105°C (Source: European Rubber Journal).

• Thermal Conductivity

  • Low values (~0.034–0.040 W/m·K) enhance its suitability for combined sound and thermal insulation (Source: ASTM C518).

Typical Industry Applications

• Acoustic panels and enclosures
• HVAC duct insulation (sound and thermal control)
• Automotive and railway noise barriers
• Equipment and machinery vibration dampening

Industry Compliance

• Fire Safety:

  • Many NBR foams comply with UL94 and EN13501-1 fire ratings, essential for building and industrial standards.

• Environmental Standards:

  • Compliant with RoHS and REACH for restricted hazardous substances in many regions.

Sourcing and Customization

• Thickness Range:
  • Typically available from 3mm to 50mm for tailored acoustic requirements.
• Color and Surface Options:
  • Standard color: black. Surface treatments may include embossing or added protective skins.

Authoritative References:

• Rubber World Magazine, Nitrile Rubber: Recent Development and Prospects, 2021.
• ASTM C518 – Standard Test Method for Steady-State Thermal Transmission.
• European Rubber Journal, “Rubber Properties & Applications”, 2023.

Summary Table: NBR Foam Quick Facts

Conclusion

Understanding what NBR foam is made of enables professionals in sound insulation materials to select the optimal solution for complex acoustic challenges. NBR foam’s unique blend of compounds and properties drives its continued adoption in high-performance applications worldwide.