When liquid silicone rubber is bonded to substrates such as metals, plastics, glass, ceramics, and PCBs, if poor adhesion, interfacial delamination, or insufficient peel strength occurs, the problem often lies not only with the adhesive itself—the substrate surface condition and associated treatment methods are equally critical.

When oil contamination, dust, mold release agent residue, or oxide layers are present on the substrate surface, bonding performance is significantly affected. Even surfaces that appear clean to the naked eye may contain trace contaminants. It is recommended to clean the substrate before bonding, such as by wiping with alcohol, plasma treatment, corona treatment, or flame treatment, to improve surface wettability and bonding strength. For plastic materials with low surface energy, surface treatment is particularly important.

The choice of primer also affects bonding performance. Different substrates and liquid silicone rubber systems have different compatibility with primers, and blindly changing primers may lead to unstable results. It is recommended to first confirm the substrate type, curing method, and application scenario, then select a matching primer solution. For liquid silicone rubber requiring self-adhesion, the substrate surface should also be ensured to be clean and dry, and protected from contamination.

In addition, curing shrinkage, hardness matching, and modulus differences also affect stress distribution at the bonding interface. Harder materials may generate greater interfacial stress during temperature changes or under load, while softer materials help relieve stress. When selecting materials, enterprises should comprehensively consider bonding strength, flexibility, temperature resistance, and long-term reliability.

Our company can provide liquid silicone rubber material selection, primer matching recommendations, and bonding testing support based on customers' substrate types and process conditions. Through preliminary validation, bonding risks in the mass production stage can be reduced.

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