Sealant Manufacturers produce adhesives and sealants that are used in a wide variety of applications. These include industrial and commercial projects such as manufacturing, transportation, and building construction. A wide range of sealant manufacturing capabilities are available including single and two-component products, primer and primerless systems, and hot-melt application systems. Many manufacturers also provide a wide array of options for the application process including gun and spatula systems as well as different types of applicators, nozzles, and mixers.
The main difference between an adhesive and a sealant is that adhesives are used to bond surfaces together in a functional manner while sealants are used to create an airtight, watertight, or waterproof finish. Adhesives are also generally less permanent than sealants, although there are exceptions to this rule.
A sealant is typically a liquid or semi-solid polymer that is applied by spraying, brushing, or troweling. Depending on the type of sealant, there are often added properties such as paint-over ability, low-temperature flow characteristics, or color. The physical properties of a sealant are important as well and may include the modulus of elasticity, stress/strain recovery characteristics, fatigue resistance, and tear strength.
When a sealant is selected for a specific project the performance requirements need to be evaluated and specified. Having a clear understanding of the movement capabilities of the joint is critical as is the substrate compatibility. It is also important to understand what other construction materials will be in contact with the sealant.
Adhesive and sealant manufacturers need to be aware of the environmental concerns in their markets. The growing interest in sustainable building practices has led to increased demand for environmentally friendly products. Some manufacturers have developed hybrid technology that combines the benefits of traditional silicone and polyurethane products with newer bio-based raw materials.
Sealants that are formulated with these newer materials offer advantages such as lower VOCs, better insulation values, and faster cure times. As these products continue to develop and evolve it is expected that they will be increasingly used in the mainstream market.
It is important to know what safety and toxicity concerns exist when working with a particular sealant. For example, epoxy sealants are typically supplied as two component systems consisting of a base and an accelerator that must be mixed together prior to application. During this reaction the product emits toxic fumes and/or heat that could present a health or safety hazard in the work environment. Metering and mixing these types of sealants can also cause dermatitis or other skin-related problems when the workers come into direct contact with the components.
Other important considerations when selecting a sealant for a project are the handling and application characteristics. The ease of use will determine how the sealant is applied, which in turn will impact how it performs. The ability to handle the sealant during its application cycle is important, as is the speed at which it can be cured and ready for use. It is also important that the sealant be capable of performing in various weather conditions, especially freezing temperatures.