Do You Know Why the “Silicone Leather” You’re Using Is Delaminating?

1. Introduction

As consumers demand higher-quality touch and durability in furniture, automotive interiors, and wearable products, materials that combine premium hand feel, long-lasting performance, and low maintenance have become essential.

Many products marketed as “silicone leather” are in fact Hybrid Silicone, where silicone components are partially integrated into PU (polyurethane) or PVC surfaces. While these materials aim to deliver soft touch, stain resistance, and weatherability, they often suffer from delamination.

It is important to understand that delamination does not mean silicone itself is breaking down. Rather, it is the adhesion failure between the silicone-containing topcoat and the underlying substrate, leading to peeling, bubbling, stickiness, or surface powdering.

This article explores the issue in depth, covering mechanisms, common manifestations, root causes, and practical solutions.

2. Mechanisms and Failure Modes

2.1 Interfacial Bonding Structure

Hybrid Silicone typically has a three-layer structure:

1. Base fabric layer – provides mechanical support

2. Intermediate PU/PVC layer – the main structural layer determining the leather’s strength

3. Silicone-modified topcoat (5–20 μm thick) – composed of silicone-modified resin, crosslinkers, and additives

Delamination is essentially an interlayer adhesion failure, which can be classified as:

• Interfacial failure – clean separation between the silicone layer and primer; often due to mismatched surface energy or lack of primer 

• Cohesive failure – fracture occurs within the silicone layer or primer, typically caused by incomplete curing or excessive internal stress 

2.2 Common Failure Manifestations

3. Causes of Delamination

Delamination results from the combined effects of material incompatibility, process control, and environmental aging.

3.1 Material Incompatibility (Fundamental Cause)

• Silicone has extremely low surface energy (~20–24 mN/m), while PU/PVC substrates are much higher (~38–45 mN/m)

• This polarity mismatch leads to:

  • Poor wetting – the silicone topcoat cannot fully spread, leaving microscopic gaps

  • Interfacial repulsion – free silicone oils may migrate to the interface, forming a barrier layer that blocks adhesion

3.2 Process Control Failures (Direct Causes)

• Insufficient crosslinking – incomplete curing in two-component (2K) systems weakens internal network strength

• Lack of primer – without adhesion promoters (e.g., silane coupling agents, chlorinated polyolefins), the silicone layer cannot chemically bond with the substrate

• Incorrect curing conditions – too low (<80°C) prevents full curing; too high (>140°C) can cause silicone degradation or plasticizer migration

3.3 Environmental Aging & Usage Factors (Triggering Causes)

• Plasticizer migration – low-molecular-weight plasticizers in PVC or soft PU migrate over time, swelling the silicone layer and weakening adhesion

• Hydrolysis – heat and humidity can break PU ester bonds, reducing primer strength and indirectly causing delamination

• Mechanical stress – repeated bending or stretching, especially with hardness mismatch between layers, accelerates peeling

4. Practical Advice and Solutions

Delamination in Hybrid Silicone is complex but manageable through careful material selection and trusted suppliers.

At Sileather, we provide only 100% silicone-coated fabrics, ensuring superior surface performance, consistent durability, and reliable quality — critical for creating high-performing, best-selling products.