Buying Guide to the Best Silicone Adhesive

Whether you need to attach two pieces of plastic or seal a leaky pipe, using the best silicone adhesive will get the job done. This buying guide will help you choose the right product for your needs.

It’s a great choice for sealing, insulating and fixing electric wiring, windshields and plumbing leaks. It also protects surfaces from moisture and prevents mold or mildew growth.

Permatex 80050 Clear RTV Silicone Adhesive Sealant

This clear silicone adhesive and sealant from Permatex is a general purpose room temperature vulcanizing (RTV) compound that quickly cures from the exposure to moisture in the air. It can be used on metal, glass, plastics, rubber, ceramic, and painted surfaces. The low-odor formula is ideal for sealing and bonding parts, repairing gaps, and securing electrical wiring. It is waterproof and flexible, and it resists aging, weathering, vibration, and chemicals. It is also non-sagging and resistant to temperatures up to 400F.

Before applying, clean the mating surface with a residue-free solvent, such as Permatex Gasket Remover, and wipe down with a cloth or rag. Apply a continuous and even bead of silicone to one surface. Allow to dry completely before using. If a bead is too thick, use an extension nozzle or aerosol tip to apply thinner beads. Remove the tip after application and store in a plastic cap. Excess cured silicone can be removed with a knife or scraper.

Permatex 80050 Adhesive is a general-purpose, clear RTV best silicone adhesive indoor/outdoor sealant that dries to a durable, tough, and smooth finish. It effectively seals, bonds, repairs, mends, and secures glass, metal, plastics, fabric, vinyl, and weather stripping. It is waterproof and flexible, and it withstands a temperature range of -75°F to 400°F and resists oil, water, weather, and vibration. It is not recommended for windshield installation or engine gasket applications.

Permatex 81173 Black Silicone Adhesive

This black silicone adhesive sealant is a low odor formula, general purpose, sensor-safe, RTV indoor/outdoor sealant that dries to a tough, flexible, rubber-like film and resists aging, weathering and thermal cycling without hardening or cracking. It effectively bonds, seals, repairs, mends and secures glass, metal, plastic, fabric, vinyl, and weather stripping, and can be used on vertical or horizontal surfaces. It insulates wires, and is oil, water, chemical, vibration and noise resistant. It can be used on windshields, door frames, hatches, electrical connections, seams and roofs, vinyl tops, and weather stripping (not recommended for engine gasket applications). Sold as a 12.9-oz cartridge. Made in USA.

Note: Clean all mating surfaces with a residue-free solvent before use. For best results, apply on dry surface. For maximum durability, allow to cure 24 hours before exposure to sunlight or heat.

Gorilla Clear Silicone Sealant Caulk

Gorilla makes a clear caulk that is aquarium-safe and non-toxic. It’s formulated to resist fading, cracking and yellowing from water exposure. It’s also non-shrinking and paintable. This caulk can be used indoors and outdoors and is resistant to weathering and UV radiation. It dries to a smooth, waterproof finish that repels mold and mildew growth. It has a high tensile strength and is ideal for adhering glass to surfaces like counters, sinks and window frames.

This type of adhesive bonds most materials, including ceramic, glass, metal and wood. Its strong bond doesn’t require the use of clamps and it dries quickly. However, it doesn’t work best silicone adhesive well on some plastics and may deteriorate over time. It is available in a variety of strengths, from the weakest for paper and foam to the strongest for metals and plastics.

There are also specialized silicones for different materials and situations, such as plumbing or outdoor construction. These caulks are formulated to handle movement and have a higher water resistance than general silicones. They are usually labeled for their intended applications. For example, epoxy caulks are formulated to adhere to most surfaces and are typically used for plumbing. These types of caulks come in double-barreled tubes that keep the resin and hardener separate until you’re ready to use them. Epoxy can also be purchased in different formulations, with some formulated for metal and others for wood, concrete or plastic.