Solvent-based adhesives are found in consumer glues, but are also used in industrial environments. You may be exposed to them if you work in printing, textiles or any manufacturing environment. It's important to know the dangers of solvents and the precautions to take when handling them, but first you have to understand what solvents are and how they are made.
WHAT IS SOLVENT BASED ADHESIVE?
Solvent-based adhesives are glue or adhesive products that are usually available in liquid form. Water, oil and gasoline-based adhesives with low boiling points are the most common. Liquids are usually thick enough to dry more easily, while aerosol packaging solutions are very popular because they dry quickly. The logic behind solvent-based adhesives is that containing the adhesive in a material that is easier to shape or spread will make it easier to apply. This allows the user to be more careful when applying the adhesive, reaching areas that are difficult to cover with solid glue. A more thorough adhesive layer will ensure effective performance.
Solvent-based adhesives are produced when the adhesive material is mixed with a suitable solvent to produce an adhesive polymer solution. This is not a simple process, as some polymers are effectively incompatible with certain solvents, the most effective solvent-based adhesives will be produced using polymers with a stable molecular structure that is complementary to the selected solvent. The polymer (synthetic or natural) is dissolved in a solvent, usually a liquid or low-boiling gasoline product, to produce a polymer solution. The polymer takes a long time to dissolve, depending on the stability of the polymer and the corrosive quality/temperature of the solvent solution. Care is taken not to speed up the process, as this can destabilize the chemical causing an ineffective binding process as well as potentially dangerous by-products. The resin is dissolved in a solvent to produce a sticky polymer solution, which can become highly adhesive when dry, as well as acting as a thermal insulator. Most commercial solvent-based adhesives also contain inhibitors to prevent them from sticking to the tube, as well as accelerators that react to exposure to moisture and light to reduce drying time.
Most multipurpose adhesives will be included in this bracket, making water solvents the most common adhesive product used in households and classrooms. Initially it was produced using natural compounds such as cellulose, rubber latex and starch, but can now be developed using synthetic materials such as polyvinyl acetate (PVA), which will improve the adhesive quality of the final compound.
Organic solvents are used to dissolve or extract materials. Adhesive drying times tend to be much faster than those with water solvents, because the faster evaporation of the solvent allows the glue and other additives to concentrate and harden. Organic solvents are much more effective in adhesive formulations than water solvents, but have become a concern given their toxicity and links to environmental problems such as global warming.
When a solvent-based adhesive is applied, the polymer solution is effectively allowed to dry quickly as the solvent evaporates. The time required will vary based on the type of adhesive solution you use, and the solvent used in the formulation. The solution needs to be given time for the solvent elements to evaporate so that only a substance such as glue remains. for aerosol cans, this can happen within seconds, but for liquid-based adhesives, this can take a while, depending on the surface and environment. Once the solvent evaporates, the glue will become stronger until there is no more solvent left in the solution, and the adhesive reaches maximum effectiveness.
Water solvent adhesives are generally not permanent or dry as quickly as organic solvents. As long as the glue has not dried, unwanted water-based adhesive spills can be removed with warm water. Some types even dissolve in water after drying. This material is generally very easy to spread and is not corrosive, so it can be used on any material without a chemical reaction. Although this ingredient is only effective on certain materials.
The strongest organic solvent adhesives will dissolve the material, effectively bonding it together when the glue dries. Many organic solvents are designed to work with certain materials, due to the molecular structure of their adhesive compounds. For example, PVC cement only works if applied to PVC. Application to other materials, including clothing, can cause major problems. This applies to many types of organic solvents and just be very careful to ensure that you do not use the wrong type of adhesive on your materials, as discussed in the next section.
PREPARING THE SURFACE
While choosing the right adhesive is important, preparing the surface is key. It's not just a matter of wiping the area of dust before applying the adhesive, as many surfaces have several layers of dirt and substances that will prevent the adhesive from working properly. We recommend that the surface be cleaned of dust or dirt before using a degreaser to remove any remaining oil or grease on the surface. Finally, the surface must be scraped to remove paint or adhesive stains. This can be done using fine-grain sandpaper or perhaps steel wool.
Due to the variety of chemicals used in solvent-based adhesives, it is important to check whether this adhesive is the most appropriate for use in the situation. Water solvents are great because they are easy to use, harmless and are semi-permanent if you only need to stick temporarily. However, organic solvents are much stronger and are prepared using bonds to water. These solvents often have enough flexibility to allow them to bond materials such as fabric or leather. However, these adhesives can be unstable, and applying the solution to certain materials can cause a volatile chemical reaction, which will not only damage the material but can also harm you.
Due to its natural resilience, paper is one of the easiest materials to stick to. However, paper can be brittle and susceptible to damage if the wrong type of glue is used.
· Paper can be stuck using a semi-permanent, pressure-sensitive adhesive, as seen on temple notes.
· Simple grade glue such as glue or chewing gum can be used as a permanent stick, but is easy to remove.
· Starch paste can be used as a water-activated adhesive that can bond thick paper and cards. A good example is wallpaper paste, which has very strong adhesion when dry.
· Latex adhesive should be used for cards that are thick and heavy and require a firm grip. It has non-corrosive qualities and is excellent for gluing paper to fabric.
· Rubber-based adhesives such as petroleum solvents can be used to mount photos. The aerosol applicator also makes the adhesive easy to apply, even on smaller surfaces.
Plastic may be difficult to stick to due to its low resistance and the potential for adverse chemical reactions if the wrong type of glue is used.
· PVA and acrylate adhesives can be used to bond plastic.
· Rubber-based adhesives that can be used in general should be effective for bonding plastic, but check the packaging first to ensure that they are plastic-friendly to prevent poor performance or corrosion.
Wood also benefits because it has high durability, so gluing is not too difficult. However, due to the density of the wood, a strong glue must be chosen to resist the force of gravity. Solvent-based adhesives are usually best used on wood, because of their strong adhesive qualities.
· Natural glues such as gum are effective for gluing smooth, low-density wood.
· PVA and acrylate adhesives will bond wood well, but have poor resistance to wet weather conditions.
· Using a specially designed wood glue formulated from PVA or natural resin is an easy way to glue wood. These adhesives are generally water resistant, but should not be used in outdoor conditions where rotting is likely to occur.
· Rubber-based adhesives, especially weather-resistant ones, are great for use on wood. The wood will not react badly to aerosol applications, and the glue can even make the wood more resistant to rust.
When it comes to solvent-based adhesives, safety should be of the utmost importance. It is important to know best practices when using these adhesives, and whether eye or mouth protection should be worn to stop inhaling fumes or irritating the skin. Organic solvents can be very dangerous if proper safety measures are not followed.
In general, water-based adhesives are quite safe so they are ideal for use in school environments. The only real problem associated with using water-based adhesives is if the user is allergic to an ingredient in the compound, most commonly latex, as this can cause skin and eye irritation. Starch paste such as wallpaper paste is the only water solvent that contains potentially dangerous substances, because the fungicide is added to prevent the growth of mold or spores in damp.
Organic solvents can pose a number of dangers to users, the first of which is that almost all organic solvents are highly flammable. Therefore, this solvent should not be used in environments where it can easily come into contact with flames. Apart from being highly flammable, this material should not be applied directly to fabric or materials that will later be exposed to flame, because there is a possibility that the material will be flammable. Always use in a well-ventilated room. Although they may seem obvious, organic solvents are dangerous and can cause a number of problems if they come into contact with the skin. Some solvents can cause skin irritation, especially if left on for a long time. There is also a risk that organic solvents can be absorbed through the skin. There is also a possibility that the glue will remain stuck to the skin and be difficult to remove, or even stick other objects to the skin. In this case (depending on the location of the glue on your body), glue spills should be cleaned immediately with warm water, and seek medical attention if the glue is still stuck. The problem here is that because solvent-based adhesives are designed to be water-resistant, they tend not to dissolve in water unless they have been freshly applied. You should also keep the room well ventilated when using organic solvents, because inhaling the vapors can cause dizziness, nausea, and breathing problems. Inhaling these vapors requires extreme caution to prevent inhaling anything. You may even consider a mask if you work in close contact with solvent-based adhesive solutions throughout the day.
Hopefully this article is useful!