Compare silicone, conventional rubber, TPE and TPU by feel, performance, processing and typical applications before selecting a custom material.

Excerpt: Silicone, rubber, TPE and TPU can all produce flexible products, but they do not behave the same. The right choice depends on performance, processing, geometry and use conditions.

Similar appearance does not mean similar performance

Flexible molded products are often described simply as “rubber.” In practice, the finished part may be made from conventional vulcanized rubber, silicone rubber, a thermoplastic elastomer (TPE) or thermoplastic polyurethane (TPU).

These material families can overlap in softness and appearance, but they differ in processing method, recovery, abrasion behavior, temperature response, surface feel, recyclability of production scrap and compatibility with other materials.

The following comparison is a starting point. Final performance depends on the exact grade and formulation.

Conventional rubber

Conventional rubber materials are crosslinked during molding. Common families include natural rubber and a range of synthetic rubbers selected for different environmental and performance conditions.

Rubber is often considered where the product needs elastic recovery, grip, cushioning, sealing or repeated deformation. Formulation can be adjusted for hardness, color and application-specific performance.

Typical strengths:

• Elastic recovery

• Broad formulation flexibility

• Good grip and cushioning potential

• Suitable for compression and rubber injection molding

• Strong fit for many molded industrial, footwear and consumer products

Points to review:

• Curing conditions and cycle time

• Flash and trimming requirements

• Odor and color expectations

• Compression set and aging behavior

• Batch consistency and compound control

Silicone rubber

Silicone is an elastomer family known for its wide temperature capability, stable flexibility and clean surface potential. It is commonly considered for products that face temperature variation, require a specific tactile feel or need a formulation designed around particular regulatory requirements.

However, “silicone” is not one universal specification. Hardness, tear strength, curing system, transparency, color and test requirements must still be defined.

Typical strengths:

• Flexibility across a wide temperature range

• Good weathering potential

• Distinctive soft-touch feel

• Available in a range of colors and hardness levels

Points to review:

• Tear performance in thin sections

• Dust attraction and surface feel

• Tooling and curing requirements

• Material cost

• Exact formulation and applicable testing

TPE: thermoplastic elastomer

TPE combines elastomer-like flexibility with thermoplastic processing. It can be melted and injection molded, which makes it attractive for high-volume products and overmolded structures.

TPE covers a broad group of materials. Different grades can vary significantly in softness, grip, compression behavior, weather resistance and bonding performance.

Typical strengths:

• Injection molding efficiency

• Broad hardness and tactile options

• Potential for overmolding onto compatible plastics

• Production scrap may be more manageable than cured rubber, depending on the process and material condition

• Suitable for complex molded shapes

Points to review:

• Heat response and permanent deformation

• Bonding to the substrate material

• Oil, chemical and UV exposure

• Shrinkage and dimensional control

• Surface migration or tackiness in certain formulations

TPU: thermoplastic polyurethane

TPU is a thermoplastic elastomer known for toughness, abrasion resistance and useful mechanical strength. It can be selected for flexible parts that need more wear resistance or structural strength than many softer TPE grades.

TPU grades can range from flexible to relatively rigid. Moisture control before processing is particularly important because improper drying can affect molding quality.

Typical strengths:

• Abrasion and wear resistance

• Tear strength potential

• Good mechanical toughness

• Injection molding capability

• Useful for flexible yet structurally demanding parts

Points to review:

• Material drying and moisture control

• Processing temperature

• Hydrolysis, UV or chemical exposure depending on grade

• Shrinkage and warpage

• Desired surface feel and hardness

Quick comparison

Which material should you choose?

Choose the material based on the product's critical requirement:

• For elastic recovery, grip or sealing, evaluate suitable rubber formulations.

• For temperature stability or a silicone-specific feel, evaluate silicone grades.

• For efficient injection molding and soft overmolding, evaluate TPE.

• For abrasion resistance and flexible toughness, evaluate TPU.

The best choice may also involve a combination of materials—for example, a rigid plastic structure with a soft TPE or TPU functional zone.

Ask for a project-specific comparison

Send ZED your product drawing, performance priorities, target hardness, use environment and expected volume. We can compare realistic material routes alongside tooling and production requirements.