Polyurethane or Silicone: Which is Better for Industrial Parts?

A rubber seal on a press wears through in two months; a silicone one lasts slightly longer but still tears from friction. Both are elastomers, but their wear resistance is fundamentally different. TIMOL polyurethane shows DIN 53516 abrasion of only 38-39 mm³, while silicone shows 150-350 mm³ — meaning silicone wears 5-15 times faster under the same abrasive loading. This article covers where each material wins and how to select the right one for your node.

What Silicone Rubber Is in an Industrial Context

Silicone (VMQ/FVMQ) occupies a unique niche among elastomers: thanks to its silicon backbone it retains elasticity in the range from -60 to +230 °C. This makes it indispensable for seals in food and pharmaceutical lines where FDA compliance and sterilisability are required, and for parts exposed to steam or high-temperature gases.

However, silicone’s mechanical properties are significantly inferior to other elastomers. Tensile strength in silicone is only 5-12 MPa, while polyurethane delivers 39-87 MPa. Tear strength per ISO 34 in silicone is 5-30 kN/m versus 40-120 kN/m for polyurethane. Under abrasive wear, silicone loses 150-350 mm³ per DIN 53516 — meaning it is suitable for seals without sliding contact but not for parts with dynamic contact.

In production environments, silicone most commonly serves as the material for seals, gaskets, and moulds where mechanical loading is minimal and temperature or chemical inertness requirements are at their maximum.

Polyurethane in Industrial Nodes: Where Silicone Cannot Replace It

TIMOL polyurethane solves problems where silicone wears too quickly. Conveyor belt scrapers sliding under load on a belt surface, rollers, bunker and pipeline linings, elevator buckets, screen decks, hydraulic cylinder rod seals under significant pressure — in all these nodes silicone would last only weeks while polyurethane operates for years.

The high hardness of polyurethane (from 50 Shore A to 70 Shore D) combined with elasticity gives a unique balance: the part absorbs impact while simultaneously resisting abrasive. Silicone is softer (20-80 Shore A) and therefore cuts and abrades easily in contact with hard material. The operating temperature range of polyurethane — from -60 to +100 °C — covers most industrial nodes outside zones of elevated heating.

Comparison Table: Polyurethane vs Silicone

The greatest contrast is on abrasion: silicone wears 3-17 times more intensively than polyurethane under identical test conditions. Silicone wins only on maximum temperature and chemical inertness.

Practical tip: if a part is simultaneously subject to abrasive loading and temperatures above +100 °C, neither material alone will give an optimal result. In such cases consider special high-temperature polyurethane formulations, or solve the problem structurally by reducing temperature in the contact zone (cooling, heat shield). Consult the TIMOL technologist about your specific node.

Where Silicone Is the Right Choice

Silicone is irreplaceable in three key situations. First — food and pharmaceutical production: silicone is FDA-compliant, sterilises easily, and does not release toxic substances in contact with product. Polyurethane in these conditions requires compatibility verification for the specific application. Second — high temperature: in zones of sustained heating above +120-150 °C, silicone retains elasticity while polyurethane begins to degrade. Third — production moulds and dies: for casting polyurethane or other materials, silicone moulds are widely used due to easy release and dimensional stability.

For gaskets performing only a sealing function without significant sliding friction and at temperatures above +100 °C, silicone also remains the correct choice.

Where Polyurethane Is the Right Choice Instead of Silicone

Polyurethane wins in all nodes with mechanical wear, dynamic loading, and vibration. Conveyor scrapers sliding on a belt under load will last several times longer in polyurethane than silicone. Hydraulic rod seals under pressure and motion require tensile strength of 39-87 MPa that polyurethane delivers but silicone cannot. Rollers, bandages, wheels, elevator buckets, tyres for warehouse carts and hoists — all of these fail quickly in silicone, while polyurethane shows a stable service life in them.

Polyurethane’s oil resistance is an important advantage in mechanical engineering: silicone swells in prolonged contact with petroleum products, while TIMOL polyurethane retains dimensions and properties.

How to Choose Between Polyurethane and Silicone for a Specific Node

The material selection algorithm is straightforward. If the working zone temperature exceeds +100 °C and FDA compliance is required, choose silicone. In all other cases where friction, abrasive, mechanical loading, pressure, or vibration is present, TIMOL polyurethane delivers a significantly longer service life and lower operating costs.

For nodes where the absence of odour or taste from the material is critical (food production), consult a technologist about the polyurethane type. The TIMOL range covers polyurethanes of varying hardness and chemical resistance for specific operating conditions.

To order a part or receive a consultation, contact us via factory contacts. Typical products for nodes of all types are in the polyurethane products catalogue, and technical information about the material is in the reference information section.

Summary: Polyurethane for Wear Resistance, Silicone for Temperature

The choice between polyurethane and silicone depends on the operating conditions of the specific part. Silicone is indispensable at temperatures above +100 °C and where FDA compliance is required. TIMOL polyurethane wins in all tasks where wear, impact, vibration, or pressure are present: wear resistance is 5-15 times higher than silicone, tensile strength 3-5 times higher, and the temperature range from -60 to +100 °C covers most industrial applications. The factory manufactures parts to drawing or sample for any industrial node.