Potting compounds

Potting. Potting of wire insulated with Tefzel has been accompHshed with the aid of a coating of a coUoidal siHca dispersion. The pots produced with a polysulfide potting compound meeting MIL-S-8516C Class 2 standards exhibit pullout strengths of 111—155 N (25—35 Ibf). 

Union Carbide Corp. Parylene conformal coatings, photoresists, developers, etchants, solder masks, potting compounds... 

Conap unit of American Cyanamid potting compounds, conformal coatings... 

In-service issues. As mentioned previously, many early service failures of bonded structure were due to adherend surface treatments that were unstable in long-term exposure to water. A majority of these problems were resolved by the adoption of surface treatments such as chromic and phosphoric acid anodize for aluminum details. The remaining few were alleviated by the adoption of phosphoric acid anodized honeycomb core and foaming adhesives resistant to water passage. Other service durability issues such as the cracking of brittle potting compound used to seal honeycomb sandwich assemblies, and subsequent delamination, have been minor in scope. 

Polyurethane-polyester copolymers, 8 Polyurethane potting compounds, 203 Polyurethane products, depolymerized, 533... 

Additions of BN powder to epoxies, urethanes, silicones, and other polymers are ideal for potting compounds. BN increases the thermal conductivity and reduces thermal expansion and makes the composites electrically insulating while not abrading delicate electronic parts and interconnections. BN additions reduce surface and dynamic friction of rubber parts. In epoxy resins, or generally resins, it is used to adjust the electrical conductivity, dielectric loss behavior, and thermal conductivity, to create ideal thermal and electrical behavior of the materials [146]. 

Quaint, A., Low Density Potting Compound, Sandia Corp., Preprint SCR-417,1961. 

The remainder of this section explores room temperature curing epoxy formulations where a great deal more flexibility is required. The most important application for this type of epoxy system is as a sealant or potting compound. 

Figure 15.13 illustrates the hydrolytic stability of various polymeric materials, determined by a hardness measurement after exposure to high-RH aging. A period of 30 days in the 100°C, 95 percent RH test environment corresponds approximately to a period from 2 to 4 years in a hot, humid climate such as that of southeast Asia. The hydrolytic stability of urethane potting compounds was not believed to be a problem until it resulted in the failure of many potted electronic devices that were noticed first during the military action in Vietnam in the 1960s. 

FIGURE 15.13 Hydrolytic stability of potting compounds. Materials showing rapid loss of hardness in this test soften similarly after 2 to 4 years in high-temperature, high-humidity climate zones.35... 

Liquid encapsulation and potting compounds, e.g., for automotive parts Thermal and RT-curing adhesives, underfiller materials Composites, fiber-reinforced, e.g., for transportation or in printed wiring boards PCB build-up materials... 

Use Intermediate, especially for quaternary ammonium compounds dehydrohalogenating catalyst corrosion inhibitor acid neutralizer potting compounds adhesives cellulose modifier. 

Use Processing and compounding aid for neoprene, Hypalon, SBR, vinyl compounds and other plastics potting compounds protective coatings paper... 

This class of condensation polymers is characteristically recognized by cross-linking from the reactions of epoxide groups. The products are useful as one of the best adhesives for cementing of rigid materials, and as potting compounds for physical protection or encapsulation of electronic devices. 

MAJOR PRODUCT APPLICATIONS bowling balls, cast polyester, foam, caulk, explosives, putties, sealants, pipe insulation, potting compounds, speckling compounds, reflective paints, golf balls, pultrusion, aerospace, marine, automotive, composites, and many more... 

Major polymer applications sealants, rocket propellant binders, electrical potting compounds, additives to epoxy, ftiel hoses and tubing, insulating glass, fuel-contact sealants... 

Anodized aluminum test panels (4 inch by 6 inch) were cut from automotive rocker panels purchased at a local dealership. Before testing cut edges were masked with a potting compound to eliminate edge effects. 

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