Adhesives are having a great time thanks in part to more packaging needs in Asian-Pacific and South American markets. A report from Business Insider says that that trend is going to keep going. A lot of people think the market will grow by 60% from $7.39 billion in 2016 to more than $12 billion by 2023.
A lot of times, when there is a lot of growth like this, the production of all the important parts has to change so that they can keep up with demand. But when it comes to hot melt glue, this isn’t true.
This has led to a shift away from organic compounds to synthetic ones that don’t put a strain on the Earth. The good news is that the man-made compounds that are taking their place are also good for the environment. Rising concern about the environment has had a positive effect on the hot melt adhesives industry. This has led to the development of more environmentally friendly adhesives and solvents, as well as more environmentally friendly manufacturing processes.
The Problem With Solvent-Based Adhesives and Cleaners
Solvent-based adhesives are used a lot in the automotive, furniture, and construction industries, and they are very common. When the polymer is broken down, a solvent is used to make the adhesive bond. Some solvents are flammable, many are poisonous, most evaporate quickly, and cleanup and handling usually require special care. Cleanup and handling usually require special care. In the end, solvents can harm the environment in a number of ways:
Soil Pollution
In the long run, solvents that get into the soil end up in the groundwater. People and animals could be killed by the solvent contamination, as well. The solvent could also get into drinking water.
Water Pollution
Soap-based adhesives leave behind a sticky residue that doesn’t dissolve very quickly in water. In other words, once they get to water, they can stay there for a long time and make people and things sick.
Air Pollution
Asthma and lung disease can happen if you breathe in the fumes from solvent-based adhesives that quickly evaporate. Most of the time, solvents that enter the body can be stored in the brain’s fatty tissue and have an effect on how well you think later on.
Developing Environmentally-Friendly Adhesives
Hot melt adhesives are made of stabilizers, additives, pigments, and polymers that are sold in solid, cylindrically shaped sticks or pellets. It’s melted and put on with a hot melt gun, sprayer, or other extrusion tool.
Because it doesn’t use solvents, hot melt makes very little pollution and has very few or no environmental effects. Like solvent-based adhesives, you don’t need special ventilation, and you won’t have to worry about fires when you use this type of glue.
So, because it’s cheap, businesses like construction and high-volume packaging have started to use this Earth-friendly adhesive, too. That’s why governments, regulatory bodies, and even environmental groups support the use of hot melt adhesives instead of solvent-based ones.
There are some synthetic adhesives that are good for the environment because they don’t have a lot (or any at all) of solvent in them, which can harm the environment. As you can see from the list, these “green” glues can have a lot of strength and are easy to use in many parts of the manufacturing market.
- Two-part, room-temperature epoxies are used.
- These are clear, single-part, silicone-based systems.
- Because they can be cured by the sun, low-liquidity glue can be used.
- Low-VOC, solvent-free hot melt glues can be used to make things stick.
- It can be hard to tell the difference between glues made with water and glues made with water-based ingredients like polyurethane foam or latex foam.
Embracing Environmentally Friendly Cleaners
A lot of cleaning solvents are bad for the environment and people who come into contact with them, just like solvent-based adhesives are bad for the people who use them. However, cleaning solvents that have been repurposed and new ones that haven’t been made yet are working to balance process times and costs with bad environmental effects.
1,1,1-trichoroethane, Methyl ethyl ketone, and Freon 113 used to be the standard solvents in the industry, but now they aren’t. Some of their less-harmful counterparts are detergents, soap, and other less expensive solvents with low VOC that are easier to use and less expensive than their more harmful counterparts.
Aqueous Cleaners
These cleaners come in three different types, and they are ranked by how acidic they are.
Acidic: Acids that can be used to remove oxide from metals, like phosphoric, hydrochloric, citric, and hydrofluoric acids.
Neutral: Work well for aluminum, but are too harsh for brass and copper to clean with them.
Alkaline: This group of caustic solvents includes sodium hydroxide and potassium hydroxide, both of which can be used to clean steel. They are used to get rid of scale, rust, and heavy oil.
Non-Chlorinated Solvents
It’s a good idea to use non-chlorinated solvents like these to get the benefits of chlorinated solvents without putting the environment at risk:
- Acetone, mineral spirits and terpenes: A lot of common non-chlorinated solvents do a good job, but they are flammable and have a lot of different drying times.
- Methyl siloxanes and oxygenated solvents: These can get rid of silicone oils, but they can get very hot and start a fire.
- Halogen-based solvents: Fluorine is a common cleaner in this class because it is less flammable, has low toxicity, and has no negative effects on the environment.
- Super-Critical Fluids (SCFs): SFCs, like high-temperature, high-compressed CO2, are great vapor degreasers, but they require a lot of money for special equipment.
Improving Efficiency for the Environment
It’s not enough for the hot melt industry to cut back on the use of harmful chemicals in adhesives and cleaners. It also needs to keep up with today’s environmental concerns. Another important part of running a green business is cutting down on waste and energy use.
In the hot melt industry, some of the best people are using tankless bulk hot melt dispensing systems to be more efficient and cut down on their footprint while keeping quality and safety the same. Uses a vacuum feed to draw adhesive pellets into a heating chamber. Tankless hot melt equipment doesn’t use tanks. In the next step, the pellets are melted on demand and quickly thrown out.
Because they only pull out a small amount of hot melt at a time, it takes less time to heat up and the adhesive doesn’t get burned. It may also help keep bulk hot melt equipment running for a long time, because there are less chances for char to clog nozzles and cause fluid seals to break down. Because you don’t waste as much product and your workers spend less time in maintenance mode, you save money and time. In some cases, material and production expenses have reportedly decreased as much as 50 to 75 percent.
Sure, the hot melt industry is doing well, but that doesn’t mean that Mother Nature has to be hurt by it. We should not have to choose between scientific progress that makes our lives better and protecting the environment. In order to get rid of bad things in the hot melt industry, start by cleaning up the adhesives that make it so good. Glue and cleaners made by humans that don’t use solvents are taking a huge bite out of the chemical footprint the hot melt industry will leave for future generations to clean.
Also, a simple thing like improving the efficiency of our hot melt machinery and systems can cut down on waste of the adhesive, cut down on energy use, and make costly machinery last longer.
