The best waterproof sealant for plastic serves as a protective barrier that seals tears, cracks, and rips on plastic. More than this, the sealants also keep out water from seeping in and blocks water from going out. Hence, it is safe to say that plastic sealants are cost-effective ways to repair cracks in plastic and protect them from further damages. Unfortunately, the best products with unparalleled functionality are not easy to come.
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Read on for the list of the best waterproof sealants for plastic and how to buy them
Contents
Best Waterproof Sealant for Plastic Review
Gorilla Waterproof Patch & Seal Tape 4″ x 10′ Black, (Pack of 1)
Create a permanent seal on your plastic with the Gorilla Waterproof Patch & Seal Tape. The tape is handy for keeping out air, moisture, and water with its thick layer and UV-resistant backing. It is also ideal for use underwater and indoor and outdoor repairs. The product comes in a 10ft long roll to give you enough to get the job done. It also has a flexible design that conforms to the surface of the crack or tear. Besides plastic use, you can also use it on rubber, roofs, and vinyl.
Pros
- Flexible leak fixer
- UV-resistant backing
- Thick adhesive layer
Cons
- The glue will stick to your scissors, and you’ll have a hard time removing it
J-B Weld 50133 Plastic Bonder Structural Adhesive Syringe – Tan – 25 ml
The J-B Weld 50133 Plastic Bonder Structural Adhesive Syringe is a multipurpose gap filling and adhesive system that bonds impressively with plastic. As a result, it is handy for filling dents and other forms of plastic repairs. The product comes with a syringe that allows you to mix and apply the solution conveniently. The syringe also has a resealable cap that prevents leaking and drying out. By implication, you can use it for more than one purpose. The sealant has a set time of 15 minutes and cures in 30 hours. It is also easy to use, and a result allows DIY regardless of your skill level.
Pros
- Higher tensile strength product
- Tough and flexible strength
- Mixing doesn’t attract air bubbles
Cons
- Takes longer to cure fully but does the job
Loctite Clear Silicone Waterproof Sealant 2.7-Ounce Tube (908570)
Another amazing product on our review of the best waterproof sealant for plastic is the Loctite Clear Silicone Waterproof Sealant. The product is ideal for sealing plastics, gaskets, toys, frames, and so much more. Hence, it is safe to call it a multi-purpose sealant that creates a waterproof seal around leaks or cracks. Although the product is best used indoors, you can also use it outdoors since it is waterproof. For significant results, we recommend that you clean and dry the surfaces before use.
Pros
- Extreme temperature-resistant
- Waterproof
- Flexible and impact-resistant
Cons
- There are reports that the bottom of the package sometimes leaks
Gorilla Clear 100 Percent Silicone Sealant
The Gorilla clear sealant is made of 100% silicone for flexible and versatile use. The sealant is waterproof, and as a result, is ready for water exposure about 30 minutes from preparation. More than plastic use, you can also use it for plumbing, doors, and windows. The product has a clear color; hence, it won’t color the surface after application. It also won’t crack or shrink with time. Due to its extreme sticking ability, you should wear gloves and goggles since it is sticky and can be a challenge to wash off.
Pros
- Waterproof protection
- Mold and mildew-resistant
- Won’t yellow or discolor
Cons
- It has a strong chemical smell that will dissipate with time
Gardner Bender 07315001126 LTB-400 Liquid Electrical Tape
It doesn’t look like much, but the Gardner Bender 07315001126 LTB-400 Liquid Electrical Tape is a handy tape for sealing plastic. The product forms a UV-resistant and waterproof coating around wires and plastic against shock and corrosion. Since it is liquid, the product dries quickly and has a drying time of 24 hours. It also forms a protective barrier against solvents, chemicals, and common fluids. A brush is built into the tip that you can use to apply to the surface conveniently. It is also ideal for use inside and outside your home under harsh conditions.
Pros
- Quick-drying formula
- Flexible in extreme temperature
- Chemical-resistant
Cons
- It dries so fast it quickly turns into clumps
Rust-Oleum 265495 LeakSeal Flexible Rubber Coating Spray, 11 oz, Clear
The Rust-Oleum brand has been around for a while and has enjoyed an excellent track record courtesy of impressive products, and this coating is not an exception. The product makes repairs across plastic surfaces easy with its firm but flexible protection. It gives a rubberized coating that seals and fills cracks and holes against moisture and rust. It also allows you to paint over it after sealing. As a result, you can effectively conceal the site or repair it. You can use oil-based or latex paints to coat the finish. The product dries to touch in 30 minutes and covers up to 8 sq.ft.
Pros
- Easy-to-use dispense nozzle
- Rust and corrosion-resistant
- Flexible watertight barrier
Cons
- It dries a little cloudy but nothing to break your deal
Flex Glue Strong Rubberized Waterproof Adhesive, 6-oz
The Flex Glue Strong Rubberized Waterproof Adhesive has a small appearance and packaging that aids maneuverability and ease of use. It is formulated for use on different surfaces and can be applied on wet and dry surfaces. By implication, it can work underwater. The product is solvent-free and is paintable. It does not drip; hence, it can be applied overhead. The small cartridges and tube packaging allow fast application. It also has an excellent holding capability that eliminates the need for braces. Not only does it bond, but it also seals and repairs, and is handy for construction, electrical, and plumbing projects.
Pros
- Clean and smooth application
- UV and mildew-resistant
- Paintable
Cons
- Some customers wished the tube could fit into a gun
Permatex 81158 Black Silicone Adhesive Sealant, 3 oz. Tube, Pack of 1
The Permatex 81158 Black Silicone Adhesive Sealant is another general-purpose sealant that effectively seals and mends plastics, metal, and various materials. The design of the sealant is such that you can apply it on vertical or horizontal surfaces. It is also flexible, and it is grease, weather, oil, and vibration-resistant. Plus, the sealant comes off clean without leaving a residue. On the downside, the applicator is a bit long; hence, not very easy to control.
Pros
- The tip applicator is a little long
- Texturizes beautifully
- Easy to remove
Cons
- Fluid enough to get on your hands
GE Sealants & Adhesives GE500 Advanced Silicone 2 Window & Door Sealant
GE Sealants & Adhesives GE500 Advanced Silicone sealant is 100%waterproof and offers exceptional protection from water. It does this by providing a reliable seal from consistent water and weather exposure. It also protects against stains that cause mildew and mold damages. The sealant is flexible and provides sturdy protection for indoor and outdoor use. It is also shrink-proof and can withstand contraction and expansion from temperature fluctuations. Plus, it works in freezing and hot temperatures and won’t discolor any surface it is used on.
Pros
- Flexible and strong
- Crack-proof
- 30 minutes ready time
Cons
- It cannot be painted over
Patch & Shield Power Tape Clear
Finally, something that does not attract messy applications. The Patch & Shield Power Tape is an all-weather stretchy sealing tape that is handy for sealing holes and cracks. The 4-inch wide tape works for outdoor and indoor use and is engineered to keep water in or out. It has a heavy-duty construction with a strong adhesive backing. As a result, it sticks to any surface and holds under any conditions. The tape is made in the USA, and this further gives credibility to its quality and standard.
Pros
- Tough and powerful adhesion
- Flexible seal
- Made in the USA
Cons
- Not easy to remove after sticking
3M Marine Adhesive Sealant 5200FC
The 3M Marine Adhesive Sealant is a high-strength gap-filling polyurethane ideal for sealing plastic, wood, aluminum, and fiberglass. It has a fast cure time of 48 hours, and the chemical content reacts with moisture to provide a flexible and strong bond below or above the waterline. Polyurethane provides a flexible and strong elastomeric bond that seals under a variety of conditions. Do note, though, that it can get tacky fast and shouldn’t enter your eyes. You can store it in a tight ziplock bag after use if you intend to use it later.
Pros
- Cures underwater
- Stays pure white
- Sticky and effective
Cons
- Hard to get off the hands without using alcohol
Window & Door Max Shield All Weather
The Window & Door Max Shield All Weather sealer is paintable and has a paint-ready time of 45 minutes. Since it is waterproof, it seals and protects against water damage in extreme weather conditions. Plus, it is durable and extremely flexible. It seals up to a 3-inch gap and stretches to over 800%. It also provides mold and mildew protection and is an excellent choice for use in places prone to moisture. You can also use it with guns for convenient application.
Pros
- 35% joint movement
- Paintable
- Easy water cleanup
Cons
- Some buyers didn’t receive the clear type
Silicone RTV 4500 Food Contact Safe High Strength Silicone Sealant, Clear (2.8 FL. Ounce)
It is not every day that you see a waterproof sealant for plastic that you can use on plastics that you use for food. The Silicone RTV 4500 Food Contact Safe High Strength Silicone Sealant has an excellent holding ability and is easy to use. It is also easy to scrape off with a razor blade, and you wipe the application area clean with ease. Not just this, the product is clear and won’t affect the color of your plastic. However, since it is silicone, it has a nasty smell that will eventually disappear. It also dries quickly and is flexible to touch.
Pros
- Easy to use
- Cures quickly
- Durable for outdoor temperature
Cons
- Some customers had a bit of trouble squeezing the tube
Liquid Rubber Waterproof Sealant – Indoor & Outdoor Coating
The Liquid Rubber Waterproof Sealant for plastic by Liquid Rubber is a nature-friendly product with an adhered, flexible membrane. It does not contain volatile organic compounds; hence, it can be used indoors and outdoors. Formulated by a brand that has been in the business for about 2000, the product is ideal for preventing water penetration and resist damage from UV and harmful chemicals. Rather than spend money on hiring contractors, you can use the waterproof sealant for plastic yourself to create a watertight seal. You can use a roller or brush to make the process easier.
Pros
- No solvent or VOC
- Water-based
- Non-flammable
Cons
- A little thin but effective
Dap 00688 All-Purpose Adhesive Sealant, 100% Silicone, 2.8-Ounce Tube
The final product on our list of the best waterproof sealant for plastic is the Dap 00688 All-Purpose Adhesive Sealant, 100% Silicone. The product is a non-toxic sealant that stays flexible and won’t crack nor shrink after a long time. It is also waterproof, hence, can be used underwater. An easy-to-use nozzle is part of the product package, and it lets you apply the sealant to surfaces with many conveniences. It also has a fast cure time and does not smell foul.
Pros
- No leaks
- Easy to cut and scrape
- Comes out thick
Cons
- No nozzle cap
Factors to Consider Before Buying a Sealant
Strength and Durability
Products differ in quality and design. This is because the sealants are from different manufacturers. Hence, you cannot compare the strength of one product to the durability of the other. The best products in the market are the ones that have fast application time and promise to remain longer on the wood. It will also help if they are fortified for usage outside the home. For example, some of the products we have listed above have UV-resistant properties that qualify them for use outdoors, especially in hot environments. Other features that you can look for include; Mold and mildew-resistant, crack-resistance, and more.
Ease of Application
Another factor that you should consider before buying a sealant is the flexibility or ease of application. The products are available in different designs and sizes. As a result, they often demand different methods of use. For example, some products are designed in spraying cans while some come in containers. Sealant in spray cans is easier to dispense at any angle; all you need to do is point and spray them. They are also easy to store since you can always use the content of the can until it runs out.
Alternatively, you can consider opting for the ones in tubes. Products in this category are also easy to use as you can attach them to caulk guns and use them. The last category is sealants in containers. For this type it requires using roller and brushes. On the downside, it is not easy to get into a tight angle. Not just this, pressure on the hands can make projects challenging.
Versatile Design
One of the best ways to make your purchase worth it is to buy a sealant for plastic that has wide usage options. The ability to use the product on different surfaces apart from plastic is handy. For example, some of the products we have reviewed are ideal for metals, vinyl, ceramics, and wood. Hence, you can get the best out of your purchase.
Color and Paint
Transparent or clear sealants are ideal for plastic and other uses. This is because they do not change the surface’s appearance but leaves it the way it was. However, if you don’t mind having colored on your plastic, then you can buy any other product that is not described as clear. Another one like it is the ability to paint on the sealant. Some products let you dab paint over the work area as an effective way to conceal the sealing. However, not all sealants are paintable. It will help if you can paint over the surface to hide the crack or tear sealed.
Set and Cure Time
The products differ in set and cure time. Cure time refers to the length of time that is needed for the chemical and physical reaction to complete. When this happens, the sealants become hard and bind effectively to surfaces. On the other hand, the set time is how long it takes to mix the different sealant elements until it is strong enough to use. Products with a short set and cure time are more efficient as they don’t require long periods to use. Hence, it will help if you buy a product with a considerably short set and cure time.
Conclusion
There you have it on our list of the best waterproof sealant for plastic. We hope you have enough information to make your purchase worth it. Happy sealing.