What is the difference between adhesives and solvents

Here is a summary of the advantages and disadvantages:. At this point it is only fair to say that at Formulated Polymers we deal exclusively with water-based, or wet bond adhesives. We do not produce solvent-based products. Having worked extensively with both solvent and water-based products over the years, we are firmly of the opinion that water-based glues are the best option in almost all circumstances. This is why we only work with water-based products now — they really are no significant downsides to using wet bond adhesives.

To find out more about the benefits of using a wet bond adhesive, or to discuss our bespoke formulation service, please get in touch with one of our team today.

Call us on , or send us a message through our online contact form. Topics: Wet Bond Adhesives. Posted by Martin Howarth on May Solvent Based Adhesives Solvent based adhesives are the most commonly used type of adhesive in some sectors, owing to their fast bonding and drying properties.

Here is a summary of the advantages and disadvantages: Advantages Bond strength Versatility — solvent based adhesives can be applied to a variety of situations. Temperature range — solvent based adhesives are not liable to freeze at low temperatures and can withstand high temperatures well although are not food safe for use in ovens.

Disadvantages Cost — solvent based adhesives are more expensive than water-based adhesives. Environmental damage — All stages of the manufacturing and application process for solvent-based adhesives, including formulation, drying and curing, release volatile organic compounds VOCs into the atmosphere.

These atmospheric pollutants are linked to a number of serious health problems in people, as well as to the formation of ground-level ozone, which contributes to global warming. They are also non-flammable, which may make it seem like the likely choice. However, they also dry much slower than solvent-based adhesives, and are somewhat limited in what they will bond.

That being said, water-based adhesives are highly resistant and can be used where plasticizer resistance is needed. Solvent-based adhesives, on the other hand, are generally used for more difficult-to-bond substrates. Designed for more demanding and long-term applications, they are ideal in industries where speed of application and production is needed. They are very durable and more chemical-resistant than water-based adhesives, and provide quite strong bond strength.

Pressure-sensitive adhesives remain viscous and don't completely solidify, so temperature and load can affect the quality of the bond they form. Sealants are much more flexible than adhesives, since they usually contain an elastomer, with a molecular structure that is loosely cross-linked and a generally paste-like consistency. This lets them fill gaps between the surfaces of components or substrates to form air-tight and water-tight barriers. Compared to adhesives, sealants generally have higher rates of shrinkage.

Sealants are usually divided into three types: one-component, two-component, and tapes. One-component types are the most common and can be easily applied, and chemistries include silicone , urethane, solvent-based acrylics , solvent-based butyls , water-based latex , silyl-modified polymer SMP , and polysulfides.

Two-component types, comprising an activator and a base component, require mixing equipment and applicators. Their chemistries include silicone, urethane, and polysulfides. Sealant tape types are most commonly butyl chemistries. When deciding what type of adhesive or sealant to choose, engineers must ask themselves several different questions to identify how it will be used in their applications. Initial questions include what is the material the object being bonded is made of and what conditions does it need to survive?

First, is it a structural or a non-structural bond? Does the bond have to support a load-bearing object? In that case a structural adhesive is required. Or it is being attached to something else that's doing the load bearing, such as rivets or welding? In that case either a non-structural adhesive or a sealant is needed, depending on the job to be done. Next, when choosing either an adhesive or a sealant, what are the substrate materials, and the thermal and environmental conditions the bond must withstand?

Some adhesives are much better at bonding to certain types of substrate materials, such as ceramic , glass , or specific metals and plastics. Environmental conditions may include the types of stresses -- compressive, tensile or torsion, intermittent or constant -- and the load, operating temperature, and chemical exposure a bond will be used in. More specialized conditions may be a need to provide thermal or acoustical insulation, electrical properties, optical properties, or UV stability, to act as a fire barrier, or to display a certain surface appearance.

Other considerations may include bonding substrates with different mechanical properties, such as different elongations under stress or different coefficients of thermal expansion. For sealants, this will require enough elongation and flexibility to accommodate the requirements of both substrate materials. Low shrinkage after application may also be required. Additional conditions for adhesives may include different types of surface preparation required, whether the bond gap must be thin or thick, whether the part is horizontally or vertically oriented, required working life and application equipment, and whether thermal or ultraviolet UV curing is needed.