BACK TO HUB
Technical

Butyl Rubber (IIR): The Ultimate Barrier for Pharmaceutical Stopper Applications.

Butyl Rubber (IIR): The Ultimate Barrier for Pharmaceutical Stopper Applications.

Share this article

Share this technical note with your engineering team.

Butyl Rubber (IIR): The Ultimate Barrier for Pharmaceutical Stopper Applications

Problem Statement

Pharmaceutical stoppers require exceptional gas and moisture barrier properties to maintain drug efficacy. Traditional materials like NBR and EPDM fail under prolonged exposure to aggressive solvents and sterilization processes, leading to compromised seal integrity.

Material Science Analysis

Butyl Rubber (IIR) excels due to its low permeability to gases and liquids. The polymer’s molecular structure, characterized by a high degree of halogenation and low unsaturation, provides superior chemical resistance and thermal stability. This makes IIR ideal for applications requiring autoclave sterilization at 121°C and exposure to aggressive solvents like ethanol and acetone.

Technical Specs

  • Shore A Hardness: 50-70
  • Tensile Strength: 10-15 MPa
  • Elongation at Break: 400-600%
  • Temperature Range: -50°C to 150°C
  • Compression Set: ≤20% (22h at 125°C)

Technical Comparison

Material Gas Permeability (cm³·mm/m²·day·atm) Chemical Resistance (Ethanol) Compression Set (%) Temperature Range (°C)
Butyl Rubber (IIR) 0.8 Excellent ≤20 -50 to 150
NBR 5.2 Good ≤35 -30 to 120
EPDM 3.6 Fair ≤25 -40 to 130

Standard Compliance

RubberQ adheres to IATF 16949 standards, ensuring batch-to-batch consistency in material properties. Our IIR formulations comply with ASTM D2000 for material callouts and ISO 3601 for sealing performance. Each batch undergoes rigorous testing for compression set, chemical resistance, and gas permeability.

For custom material compound development or IATF 16949 documentation, consult RubberQ’s engineering department.

Share this article

Share this technical note with your engineering team.

Subscribe to Technical Updates

Receive new material insights and engineering case notes directly by email.

Related Articles

Apr 05, 2026

Liquid Silicone Rubber (LSR) Tooling: Why Initial Investment Pays Off in Precision.

Liquid Silicone Rubber (LSR) Tooling: Why Initial Investment Pays Off in Precision Problem Statement High-cycle manufacturing of precision components, such as EV battery seals and AI server gaskets, demands materials with exceptional dimensional stability and chemical resistance. Traditional elastomers like EPDM and NBR often fail under extreme thermal cycling and aggressive chemical exposure, leading to […]

Read article

Apr 05, 2026

High-Tonnage Vulcanization: Managing Large-Scale Industrial Rubber Components.

High-Tonnage Vulcanization: Managing Large-Scale Industrial Rubber Components Problem Statement Large-scale industrial rubber components, such as conveyor belts and hydraulic seals, face premature failure under high-tonnage vulcanization. Common issues include chemical degradation at temperatures exceeding 200°C and compression set failure during high-pressure cycles. Material Science Analysis Standard EPDM polymers fail under extreme heat due to their […]

Read article

Apr 05, 2026

Commercial Aircraft Interiors: Meeting Smoke and Toxicity Standards (FST).

Commercial Aircraft Interiors: Meeting Smoke and Toxicity Standards (FST) Problem Statement Polymer components in aircraft interiors must pass FAR 25.853 flammability tests while maintaining mechanical performance. Standard EPDM fails at 180°C with toxic smoke emission (HCN >100 ppm). Material Science Analysis Chloroprene rubber (CR) releases HCl gas during combustion. Fluorosilicone (FVMQ) provides superior thermal stability […]

Read article

Need technical consultation?

Our engineering team can help apply these material insights to your specific project.

REQUEST A QUOTE