Which membrane materials and fabrics are used in membrane structures

Materials used in membrane structures are diverse, each offering unique properties tailored for specific applications. Below is a classification based on material type and functionality:

I. Classification by Material

1. PTFE Membrane (Polytetrafluoroethylene-Coated Fiberglass Fabric)

• Structure: Fiberglass substrate coated with PTFE resin.
• Features:
  • High durability: Service life exceeding 25 years; UV-resistant, corrosion-resistant, and aging-resistant.
  • Self-cleaning: Smooth surface minimizes dust adhesion; cleanable via rainwater.
  • Adjustable translucency: 5%–15% light transmission blocks UV while diffusing natural light.
  • Fire resistance: Compliant with B1 fire rating and international building codes.
• Applications: Permanent structures (e.g., stadiums like the Bird’s Nest), airport terminals, convention centers.

2. ETFE Membrane (Ethylene Tetrafluoroethylene Copolymer)

• Structure: Extruded ETFE resin film, used as single or multilayer inflated panels.
• Features:
  • Lightweight yet strong: 1% the weight of glass with high tensile strength; resists wind/snow loads.
  • High transparency: Up to 95% light transmission; regulates indoor light and temperature.
  • Self-cleaning: Non-stick surface sheds dust with rain.
  • Eco-friendly: Recyclable and non-toxic when burned, aligning with green building standards.
• Applications: Inflatable domes (e.g., London Olympics’ Water Cube), skylights, and architectural installations.

3. PVC Membrane (Polyvinyl Chloride-Coated Polyester Fabric)

• Structure: Polyester fabric coated with PVC resin, plasticizers, and anti-aging additives.
• Features:
  • Cost-effective: ~1/3 the price of PTFE, ideal for budget projects.
  • Easy processing: Weldable and cuttable for complex designs.
  • Color variety: Available in multiple hues for aesthetic flexibility.
  • Moderate durability: Service life ~10–15 years; requires periodic maintenance.
• Applications: Temporary structures, awnings, advertising canopies, stadium covers.

4. PVDF Membrane (Polyvinylidene Fluoride-Coated Polyester Fabric)

• Structure: PVC membrane with an additional PVDF resin coating.
• Features:
  • Enhanced weather resistance: Superior UV/chemical resistance; lifespan extends to 15–20 years.
  • Improved self-cleaning: Smoother surface reduces dust retention.
  • Retains flexibility: Maintains PVC’s workability for easy installation.
• Applications: Mid-life projects (e.g., commercial street canopies, exhibition halls).

5. Silicone-Coated Fiberglass Fabric

• Structure: Fiberglass substrate coated with silicone rubber.
• Features:
  • High-temperature resistance: Operates in -70°C to +250°C environments.
  • Fireproof: Meets Class A fire standards for high-safety applications.
  • Low translucency: Ideal for shading requirements.
• Applications: Fireproof curtains, industrial sunshades, duct expansion joints.

II. Classification by Function

1. Translucent Membranes (e.g., ETFE, PTFE): Skylights and installations requiring natural light diffusion.
2. Sunshade Membranes (e.g., PVC, PVDF): Awnings, stadium covers for solar protection.
3. Fireproof Membranes (e.g., silicone-coated fiberglass): Fire-rated partitions, industrial shade systems.
4. Tensioned Membranes (e.g., PTFE, ETFE): Span large areas using cables or masts for open-space structures.
5. Inflatable Membranes (e.g., ETFE multilayer systems): Air-supported structures like domes or stadiums.

III. Material Selection Guidelines

• Permanent structures: Prioritize PTFE or ETFE for durability, light transmission, and self-cleaning.
• Temporary/low-budget projects: Opt for PVC/PVDF to balance cost and functionality.
• Special environments: Use silicone-coated fiberglass for extreme heat/fire safety; ETFE for maximum transparency.
• Complex designs: PVC/PVDF’s flexibility suits unconventional shapes.