Liquid Adhesive Converts to a Hot Melt When Heated

The Liquid Polymer Co., Lorain, Ohio, a developer of liquid polymer formulations, has introduced Liquamelt™, a nanocomposite hot melt adhesive. A free-flowing liquid, it converts into a hot melt when heated. This adhesive has all the advantages of hot melts, but it does not need traditional hot melt equipment to be processed and applied. The adhesive converts from a liquid to a molten hot melt when it is pumped through a heat exchanger about the size of a coffee cup.

In essence, expensive and hard-to-maintain hot melt systems can be replaced with two simple components — a heat exchanger and a heated dispensing head. Fusion melting of the liquid adhesive occurs in an environment sealed from atmospheric oxygen, so oxidative degradation is eliminated. The first-in, first-out flow characteristics of an in-line heat exchanger minimize the time the adhesive is exposed to melt temperature, so thermal degradation is greatly reduced. These two factors make adhesive char and nozzle plugging very unlikely. The costs of line downtime caused by char-plugged nozzles are very high, but so are the manpower and spare-parts costs necessary to avoid them.

The new liquid adhesive greatly simplifies the process of thermoplastic adhesive application. All the benefits of hot melts stay, but the high cost of constant operator attention, maintenance, spare parts and equipment failure disappear.