Silicone and EPDM in the food industry. Comparison of physical and chemical properties
Selection of the appropriate elastomer in food processing installations
The selection of the appropriate elastomer in food processing installations has a direct impact on process safety, component durability, and compliance with applicable standards for materials in contact with food. In industrial practice, two materials are most commonly used: silicone and EPDM. Although both are widely applied in seals and components in contact with food, their physical and chemical properties differ sufficiently that improper selection may lead to reduced installation lifespan, more frequent component replacement, or unplanned downtime.
In this article, we present a detailed comparison of both elastomers, taking into account their resistance to temperature, CIP/SIP cleaning agents, fats, steam, and ageing factors. Our objective is to facilitate an informed material selection for specific operating conditions in the food industry.
How does material ageing affect elastomer lifespan in the food industry?
Material ageing is a process of gradual loss of physical and chemical properties under operational conditions. This phenomenon is unavoidable, but its rate depends on the material type and working environment. In the food industry, ageing is of particular importance as it directly impacts production safety, hygiene, and reliability of components in contact with food. Factors such as UV radiation, chemicals, high temperature, and mechanical loads can significantly accelerate elastomer degradation, leading to loss of elasticity, cracking, or deformation.
Chemical factors
Contact with aggressive media — such as CIP/SIP detergents, alkalis, acids, and disinfectants — may gradually weaken the elastomer structure. If the material is not properly selected for operating conditions, prolonged exposure to such substances leads to swelling, hardening, and ultimately cracking and loss of functional properties.
Physical factors
Components in food processing installations are exposed to cyclic mechanical loads, compression, stretching, and vibrations. Additionally, process equipment generates heat, which may accelerate elastomer degradation. Over time, this results in loss of elasticity, increased permanent deformation, and reduced sealing performance.
Environmental factors
UV radiation, moisture, and variable environmental conditions may significantly affect material durability, especially plastics and elastomers. UV accelerates oxidation processes, causing brittleness and cracking, while high humidity may lead to hydrolysis of certain polymers.
Resistance of silicone and EPDM to chemical, physical, and environmental factors
Silicone
Silicone is characterized by very good resistance to detergents and disinfectants, making it suitable for applications requiring frequent cleaning. Its main advantage is stability across a wide temperature range — it maintains flexibility at both low and very high temperatures. Additionally, silicone exhibits excellent resistance to UV radiation and ozone, making it suitable for environments exposed to light and weather conditions.
EPDM
EPDM is characterized by very high resistance to alkalis, CIP/SIP detergents, and hot water, making it one of the best materials for cleaning installations and CIP processes. Physically, it is stable, withstands cyclic loads well, and maintains flexibility even under intensive operation. In outdoor environments, EPDM ages slowly due to high resistance to UV, ozone, and steam, resulting in long service life in water and alkaline applications.
Silicone or EPDM – comparison of physical properties and chemical resistance
Silicone and EPDM are the two most commonly used elastomers in the food industry, and their physical properties and chemical resistance determine their suitability for specific applications.
Silicone stands out for its exceptional stability across a wide temperature range, maintaining flexibility both in deep freezing conditions and at high process temperatures. This makes it ideal for installations with frequent temperature fluctuations or where elasticity must be maintained under extreme conditions. Additionally, silicone demonstrates good resistance to detergents and disinfectants, making it suitable for components subjected to regular cleaning.
EPDM, on the other hand, offers very high chemical resistance to alkalis, CIP/SIP detergents, and hot water, making it one of the most reliable materials for cleaning and disinfection applications. From a physical standpoint, EPDM performs well under cyclic loads, maintaining dimensional stability and flexibility even during intensive use. Its high resistance to UV, ozone, and weather conditions ensures long service life in outdoor environments and installations exposed to high humidity and steam.
Both materials therefore have clear strengths: silicone provides excellent thermal stability and resistance to light-induced ageing, while EPDM stands out for its resistance to cleaning chemicals and durability in water and alkaline environments. As a result, the choice between silicone and EPDM depends primarily on operating conditions and the type of loads affecting a given component.
Temperature resistance of silicone and EPDM
Temperature resistance defines a material’s ability to retain its properties under varying or extreme thermal conditions. High temperatures can accelerate ageing processes and cause direct damage such as loss of elasticity, deformation, or cracking. In the food industry, this is particularly important because installation components often operate at elevated temperatures, are subjected to CIP/SIP cleaning processes, or exposed to rapid thermal changes. Materials with high temperature resistance ensure dimensional stability, longer service life, and safe operation in demanding processes.
Silicone and EPDM under high and low temperature conditions
Silicone and EPDM differ significantly in terms of temperature resistance, which influences their application in the food industry. Silicone is distinguished by an exceptionally wide operating range — it maintains flexibility at both very low and high temperatures, making it suitable for applications exposed to frequent thermal changes and processes requiring material stability under high thermal loads.
EPDM, on the other hand, offers very good resistance to elevated temperatures in water and steam environments, making it a reliable material for CIP/SIP installations and applications involving hot water or steam. Both elastomers provide stable performance, but their selection depends on process specifics and temperature range.
Standards and requirements for materials in contact with food – silicone and EPDM
Silicone and EPDM used in the food industry must meet stringent material safety standards. Requirements such as those set by FDA (Food and Drug Administration) and BfR guidelines define which components may be used in elastomers and permissible levels of substance migration into food. This ensures that materials do not adversely affect taste, odor, or quality of food products.
Silicone, due to its purity and chemical stability, often meets the most demanding food contact standards, making it a popular choice for applications requiring high hygiene and temperature resistance. EPDM, in turn, offers excellent resistance to cleaning agents and CIP/SIP processes, while also being available in FDA- and BfR-compliant versions for safe use in food installations.
Both silicone and EPDM must undergo appropriate testing and possess certifications confirming compliance with applicable regulations. This ensures that materials are safe, durable, and meet international quality standards.
Silicone and EPDM for the food industry in the Power Rubber offer
At Power Rubber, we offer high-quality silicone and EPDM intended for use in the food industry. Our materials meet required safety standards, are resistant to intensive use, and adapted to operation in demanding process conditions.
If you are looking for certified elastomers for your installation, check our offer or contact us by phone at +48 22 292 40 24 or +48 505 16 03 03, by email (Power@PowerRubber.com), or via our contact form — we will help you select the right material for your needs.