Changfu Chemical Mercapto-Modified Polysiloxane: High-Efficiency Protective Coating Solution for Circuit Boards

Conformal coatings are specialized coatings used to protect circuit boards and related electronic equipment from harsh environments. They offer moisture resistance, mold resistance, dust resistance, corrosion resistance, and salt spray resistance. Traditional conformal coatings suffer from surface oxygen inhibition during UV curing, leading to incomplete curing, low efficiency, and increased costs due to the need for higher photoinitiator dosages or additives like nitrogen gas or reactive amines. By utilizing Changfu Chemical’s thiol-modified polysiloxane and vinyl-modified polysiloxane to formulate a UV-moisture dual-curable three-proof coating, these issues are effectively resolved. 

Under UV irradiation, a photoinitiated "click" reaction occurs between thiol and vinyl groups. The photoinitiator absorbs UV energy to generate free radicals or active intermediates, triggering a rapid reaction between thiol and vinyl groups to form stable chemical bonds, enabling swift curing. The high reactivity of thiol and vinyl groups, coupled with their insensitivity to oxygen, eliminates surface oxygen inhibition common in traditional free radical photoinitiation systems, significantly improving curing efficiency. 

Performance Advantages 

- Superior Weather Resistance: The polysiloxane backbone offers exceptional weather resistance, enabling the coating to withstand UV radiation, ozone, rain, wind, and other environmental factors. This ensures long-term protection for circuit boards while maintaining performance integrity. 

- Excellent Chemical Resistance: Polysiloxane’s chemical stability resists corrosion from acids, alkalis, salts, and other chemicals, safeguarding circuit boards and extending the lifespan of electronic devices. 

- Outstanding Electrical Insulation: The coating’s excellent electrical insulation properties isolate circuit boards from external environments, preventing electrical failures such as leakage or short circuits, thereby ensuring device safety. 

Cost Advantages 

- Reduced Photoinitiator Usage: The high reactivity of thiol and vinyl groups enables rapid curing with minimal photoinitiator, lowering production costs. 

- No Need for Nitrogen or Reactive Amines: Unlike traditional free radical systems requiring nitrogen gas or reactive amines to mitigate oxygen inhibition, this dual-cure system eliminates such additives, simplifying production and reducing material costs. 

Application Advantages 

- Broad Compatibility: Suitable for diverse electronic devices and circuit boards in consumer electronics, automotive electronics, industrial controls, aerospace, and more, meeting varied protection needs across industries. 

- Mild Curing Conditions: The UV-moisture dual-cure system operates under gentle conditions (no high temperature or pressure), minimizing thermal impact on substrates and sensitive components. This ensures compatibility with delicate electronics and complex circuit board geometries, enhancing production flexibility and applicability.