EPDM foam is a rubber elastic foaming material derived from **ethylene propylene diene monomer (EPDM)** as the base material, obtained through internal mixing and vulcanization foaming. It is categorized into **closed-cell and open-cell** types, primarily featuring **weather resistance, sealing, vibration damping, and thermal insulation**, making it a commonly used industrial foam for outdoor and high/low-temperature applications.
一、core performance
✅ Advantage
- Excellent weather resistance and aging resistance: ozone resistance, UV resistance, long-term outdoor exposure is not easy to crack and pulverize; Working temperature -40 ℃~130 ℃, low temperature does not harden, high temperature does not stick.
- Closed cell waterproof and moisture-proof: The closed cell foam is independent, with low water absorption, airtight and dustproof, suitable for waterproof sealing.
- Good rebound and minimal permanent compression deformation: excellent rebound after long-term compression and long sealing life.
- Resistant to weak acids and bases, insulated; UL94-V0 flame retardant can be customized; Support ROHS and REACH environmental protection.
- It can be laminated, die cut, stamped, and divided into gaskets and sealing strips.
❌ shortcoming
- Not resistant to mineral oil, gasoline, organic solvents, and heavy oil pollution environments are not suitable for selection.
- Closed cell sound absorption is generally good; Opening the hole is necessary for sound absorption, but it can absorb water.
二、Closed cell vs open cell EPDM (selection focus)
Closed cell EPDM (most commonly used in the market)
The bubbles are independent of each other and are not breathable or permeable
- Usage: Sealing gasket, outdoor cabinet/distribution box sealing, automotive sealing strip, door and window sealing, thermal insulation buffer
- Features: Waterproof, dustproof, pressure resistant and well sealed; Poor sound absorption
Open hole EPDM
Interconnected pores, breathable and permeable
- Purpose: Interior sound-absorbing and soundproofing filling
- Features: Good sound absorption; Not waterproof, cannot be used for outdoor sealing
三、Main application scenarios
- Automotive/New Energy: Battery pack sealing, door sealing strips, air conditioning insulation pads, chassis cushioning
- Electronic communication: outdoor base station, distribution box shell sealing gasket
- Building HVAC: door and window sealing strips, air conditioning duct insulation
- Rail transit, equipment box: gap sealing, shock absorption and buffering
四、Simple comparison with CR and EVA foam
| Material |
Core strengths |
typical scenario |
| EPDM foam |
Weather resistant, high and low temperature resistant, waterproof |
Outdoor, high and low temperature sealing |
| CR foam |
Oil resistant, flame retardant, buffering |
Internal equipment, precision electronics |
| EVA foam |
Cheap, well cushioned |
Packaging lining, not suitable for outdoor use |
五、Common parameter reference
- Density: 100-750 kg/m ³; Thickness 0.5-50mm; mostly black in color, other colors can be customized
- Closed cell rate: High quality closed cell EPDM can reach over 90%; Can be backed with single-sided/double-sided strong adhesive。
Regarding EPDM, Foshan Zhiwei Adhesive Products Co., Ltd. has over 20 years of professional matching solution experience. We welcome inquiries and contact email from major manufacturers：yang@fszw-tapes.com。
