What Are Adhesives & Sealants?
Adhesives and sealants for electronics include thermal adhesives, epoxies, conformal coatings, potting compounds, threadlockers, and RTV sealants. These materials bond, protect, seal, and insulate electronic assemblies. LCSC stocks 2,000+ adhesive and sealant SKUs.
Adhesives & Sealants — Definition and Sub-Categories
Electronic adhesives and sealants are chemical compounds used to bond components to substrates, protect circuits from environmental exposure, seal enclosures, and manage thermal interfaces in electronic assemblies.
|
Sub-Category |
Function |
Key Parameters |
|
Thermal Adhesives |
Bond heatsinks while conducting heat |
Thermal conductivity (W/mK), cure type, bond strength |
|
Epoxy/Structural |
High-strength bonding for components and housings |
Cure time, strength (psi), temperature resistance |
|
Conformal Coating |
Thin protective film over PCBAs |
Material (acrylic/silicone/polyurethane), cure method |
|
Solder Paste |
Solder alloy paste for reflow assembly |
Alloy (SAC305, Sn63Pb37), mesh size, flux type |
|
Thread Locker |
Prevent screw loosening from vibration |
Strength (low/medium/high), cure time |
How to Choose: Adhesives & Sealants Selection Guide
Match adhesive chemistry to your application: cyanoacrylate for fast bonding of non-structural joints, epoxy for high-strength structural bonds, silicone for flexible seals and high-temperature environments, and thermal adhesive where heat transfer through the bond line is required. For PCB protection, choose conformal coating type based on your environment: acrylic for general use, silicone for extreme temperatures, polyurethane for chemical resistance.
Adhesives & Sealants Comparison
|
Adhesive Type |
Cure Time |
Temp Range |
Bond Strength |
Application |
|
Cyanoacrylate (super glue) |
Seconds |
Up to 80°C |
Moderate |
Quick component tacking |
|
2-part Epoxy |
5 min–24 hours |
Up to 150°C+ |
Very high |
Structural bonding |
|
Thermal Adhesive |
Minutes–hours |
Up to 200°C |
Moderate |
Heatsink bonding |
|
Silicone RTV |
24 hours |
Up to 250°C |
Low–moderate |
Sealing, potting, gaskets |
|
Conformal Coating |
Minutes (UV cure) |
Up to 125°C |
N/A (thin film) |
PCB environmental protection |
Why Source Adhesives & Sealants from LCSC Electronics
LCSC stocks 2,000+ adhesive and sealant SKUs, enabling engineers to add assembly materials to component orders without sourcing from separate chemical suppliers.
Frequently Asked Questions
Q: What is conformal coating and do I need it?
Conformal coating is a thin protective layer applied over assembled PCBs to protect against moisture, dust, chemicals, and temperature extremes. You need it if your product operates in harsh environments (outdoor, automotive, marine, industrial) or where condensation may occur. Common types are acrylic (easy rework), silicone (extreme temps), and polyurethane (chemical resistance).
Q: What thermal adhesive should I use for heatsinks?
For permanent heatsink mounting, use thermally conductive epoxy (1–3 W/mK) for strong bonds. For situations requiring removability, use thermal tape or thermal paste with a mechanical clip instead. Never use non-conductive adhesive under a heatsink — it creates a thermal insulating layer.
Q: What is solder paste and how is it used?
Solder paste is a mixture of tiny solder balls and flux, applied to PCB pads through a stencil before component placement. During reflow soldering (heating the entire board), the paste melts and forms solder joints. It’s the standard method for surface-mount component assembly.
Q: How do I choose thread locker strength?
Low-strength (purple) for small screws that need frequent removal. Medium-strength (blue) for general fasteners — removable with hand tools. High-strength (red) for permanent bonds requiring heat to disassemble. Medium-strength is the most common for electronics enclosure screws.