(5)Selecting the best catalyst A catalyst determines many of the final properties of a STYCAST system. It's selection is as important as that of the resin as it has a significant influence on final cured hardness, mixed viscosity, temperature capabilities and physical properties. Understanding viscosity Viscosity is the measure of the internal resistance of friction when a material moves against itself. It is typically measured using a rotating spindle instrument (viscometer). The amount of force required to turn the spindle (torque) at a selected speed (rpm) is measured. A simple calculation converts this internal resistance to viscosity. Thicker materials equates to higher torque values, hence, higher viscosities./Asset/a1146.jpg
Robert McKeown offers a variety of adhesive and sealant products for a wide range of commercial and industrial applications. Our silicone epoxy adhesives and sealants, in particular, are ideal for applications such as:
FEATURES AND USES OF ELECTRONICS SEALANTS AND ADHESIVES
Providing ultimate reliability and longevity, our electronics adhesives and sealants can be used to form bonds to many different surfaces and substrates, including:
Ceramics
Metals
Glass
Filled plastics
These specialized solutions eliminate the need for mechanical fastening and clamping while allowing for optimal ease of processing. Reliable and efficient in temperatures ranging from -45 °C to 200 °C, our electronics adhesives and sealants provide excellent dielectric insulation.
Most silicone formulations are solventless, eliminating the need for special storage, ventilation, or handling. And because many of our electronics adhesives and solvents are reworkable, they offer great flexibility and allow for easier module repair.
Electronics adhesives and sealants are frequently used in: automotive, communications, industrial, and energy industries, as well as consumer devices.
Automotive
Communications
Industrial
Energy Industries
Consumer Devices
Extremely versatile, these adhesives can be used for:
Sealing lids and housing grooves
Cushioning or stabilizing fragile components
Affixing components such as capacitors and coils to circuit boards
Adhering module lids and baseplates
Gasketing
SILICONE ADHESIVES
One of the most popular types of electronics adhesives, silicone adhesives provide excellent flexibility and high heat resistance, making them ideal for electrical, automotive, aerospace, and construction industries. There are several varieties of silicone adhesives available, including:
Two-component systems that require a curing agent
One-component systems that cure through air moisture
UV or EB radiation curing adhesives
Pressure-sensitive versions that adhere to surfaces with little pressure
RTV sealants (room-temperature vulcanizing) begin to cure as soon as they’re exposed to moisture in the air, so they must be used quickly. Pressure-sensitive sealants offer a permanent tackiness. UV- or radiation-cured sealants, on the other hand, require UV light to cure, while thermoset silicone sealants require heat to cure. Although not as strong as other sealants or adhesives, electrical silicone sealants remain flexible even when fully dried or cured. Various types of silicone sealants serve as ideal solutions for high-heat applications like engine gaskets.
In electronics fabrication, silicone adhesive sealants are often used for fixing parts on circuit boards, LCD module assembly, general sealing, and component protection. Specific formulations differ depending on intended use and can be customized to allow for enhanced thermal conductivity, superior protection of metal electrodes, and faster cure times. These sealants are available in chemical-, heat-, mildew-, and oil-resistant formulations to meet a wide range of application needs.
Industrial silicone epoxy is used for:
General-purpose fixture sealing of tubs
Windows, ductwork
Gaskets
General-purpose bonding
Sealing
THERMAL SEALANTS
High temperatures often present problems for conventional adhesive materials and can affect printed circuit boards and assemblies. At Robert McKeown, we offer the highest-level special adhesive grades of thermal sealants, which allow for enhanced thermal conductivity. Both low-viscosity liquids and non-slump formations are available in two-cure chemistries.
We also offer one-part moisture-cure grades, which use room-temperature processing to cut back on equipment needs. After cure, the materials form strong but flexible bonds, which protect from mechanical stress and vibration. Both one- and two-part heat-cure solutions accelerate processing and support high throughput production.
Heat resistant silicone adhesives are extremely versatile materials and dispense easily at room temperature, but can also cure quickly at any thickness level at temperatures as low as 90°C. Efficacy and functionality are improved when higher temperatures accelerate cure times.
CHEMICAL RESISTANT ADHESIVES
Chemical resistant silicone adhesives are commonly used in:
Chemical processing plants
Chemical piping and tanks
Medical devices
These adhesives can reliably protect against a wide range of chemicals and harsh materials, including acid, alcohol, and fuel. Depending on specific application requirements, they can also provide resistance against solvents, bases, sterilization, and water.
EPOXY BASED ADHESIVES
Epoxy based adhesives are created by mixing a resin and a hardener. Curing is initiated when the resin is mixed with a certain catalyst. The covalent bonds resulting from this combination determine the rigidity and strength of the epoxy sealant.
Epoxy adhesives can reliably adhere to a variety of materials and are ideal for applications demanding chemical resistance, high strength, and low stress. Thermally conductive, microelectronic-grade, general-purpose, high-temperature and chemical resistant epoxy adhesives are available as both one- and two-part solutions. Epoxy adhesive and sealants allow for room temperature, thermal, or UV-curing capabilities.
Learn More
Robert McKeown Co., Inc. is proud to be a leading distributor of electronics adhesives and sealants for a wide range of applications. Family-owned and operated since 1937, we’re committed to constant innovation and improvement in everything we do. We offer a wide range of electronics adhesives and electronics sealants to meet all types of application needs; whether requiring flexible processing, simple assembly, strong adhesive performance, or thermal management, our clients are guaranteed top-quality, long-lasting products. Our expert staff works closely with customers to ensure solutions meet their unique requirements.
For more information on our electronics adhesives and sealants and to learn how they can help with your next project, request a quote today.
