A reasonable choice of DOW CORNING sealing/adhesive:
DOW-CORNING sealing/adhesive can be selected for the bonding of electronic components, in order to choose a reasonable product, see the following factors:


■ Single/two-component heat-curable seal/adhesive saves processing time. The higher the temperature, the shorter the curing time. If heat curing is not feasible, room temperature curing products can be selected.
■ Single-component potting adhesive is easy to operate, two-component potting adhesive can usually shorten the processing time, most products 1:1 mixing, a few 10:1 mixing.
■ When bonding components, non-collapsing and non-flowing products are usually selected.
■ If the components are power or heating devices, choose high thermal conductivity products.
■ Many products are UL and MIL certified.


Second, DOW CORNING sealing/adhesive characteristics:
It is achieved by surface bonding, which can be used to strengthen joints and seal gaps to avoid liquid or gas infiltration, to protect precision devices and play a strengthening role. Key features of DOW CORNING's seals/adhesives include:
■ Excellent electrical performance
■ Good weather resistance
■ High low temperature stability
■ Good adhesion to a variety of materials
■ Can be cured by heat or room temperature


Comparison and advantages of DOW CORNING sealing/adhesive with other different materials:
■ Epoxy seal/adhesive: can be bonded with a variety of materials, can be heated at room temperature or high temperature curing, universal epoxy seal/adhesive is unstable at high temperature.
■ Polyurethane seal/adhesive: can be bonded with multiple materials, wide range of use. Although the polyurethane seal/adhesive is very resistant to oil and chemical attack, it has a good adhesion to metal in the case of no primer
Can not be good.
■ Silicone sealing/adhesive: widely used due to its strength, service life and stress relief characteristics. DOW CORNING seals/adhesives are particularly high quality for their high and low temperature stability, excellent electrical properties and weather resistance.


DOW CORNING seals/adhesives have a variety of modes of curing systems and product options. In terms of bonding properties, various curing systems have different advantages and disadvantages. In order to achieve the curing performance and bonding effect, the contact surface should be cleaned, correctly treated and the use method should be paid attention to, if necessary, the use of primer should be considered.


5. Product classification (according to curing method) :
■ Addition molding:
There are no curing by-products, and the curing time can be shortened by heating. Most additive forms are single-component, and some two-component products are available. Curing agent action can be inhibited in additive products, such as some plastics, cutting oil on the contact surface, some solder paste and sulfur-containing substances may inhibit the performance of curing agent, in order to avoid such problems, simple compatibility tests can be performed before application.


■ Condensation type:
(1) Single-component condensation type products: curing at room temperature with the moisture of the external environment, some can also be heat curing, and some can be fast room temperature curing. Condensation curing does not reverse or inhibit the possibility of curing, however, they cannot achieve the effect of deep curing in a sealed box.
(2) Two-component condensation products: curing by relying on the moisture contained in the product itself, however, they may be reversed in the case of too thick and high-temperature sealing.

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