Pitting and bubbling artefacts in surface replicas made with silicone elastomers

Area of Science:

• Materials Science
• Polymer Chemistry

Background:

• Epoxy resin replicas are widely used in various scientific fields.
• Silicone rubber impression materials are frequently employed for creating these replicas.
• Surface artefacts like pitting and bubbling can compromise replica fidelity.

Purpose of the Study:

• To investigate the causes of pitting and bubbling artefacts in epoxy resin replicas.
• To identify factors influencing the formation of these surface defects.
• To provide insights into preventing mould degassing during epoxy curing.

Main Methods:

• Analysis of epoxy resin replicas exhibiting pitting and bubbling.
• Examination of silicone rubber impression materials and their curing process.
• Correlation of artefact occurrence with silicone polymerization parameters and material properties.

Main Results:

• Pitting and bubbling occur at the mould-epoxy interface during epoxy curing.
• These artefacts are attributed to gas escaping from the silicone rubber mould material.
• Factors such as silicone polymerization duration, base-catalyst ratios, and object surface porosity influence artefact formation.

Conclusions:

• Mould degassing is the primary cause of pitting and bubbling in epoxy resin replicas.
• Controlling silicone rubber polymerization and material composition can mitigate these artefacts.
• Understanding these factors is crucial for producing high-quality epoxy replicas.