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

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.
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