Synthetic glues like Elmer's are made of polyvinyl acetate (PVA) emulsions. The word emulsion refers to the fact that the PVA particles have been emulsified or suspended in water. The thinner the glue, the more water it has in it.Continue Reading
In addition to water and PVA, synthetic glue can also contain ingredients like ethanol, acetone, and amyl acetate. Ethanol slows down the drying time, acetone speeds up the drying time, and amyl acetate slows down the evaporation of the glue. However, some natural glues – called hide glues or protein adhesives – are made from animal proteins or gelatin. This is why people often speak of dead horses being sent to the glue factory.
Humans have been experimenting with animal-based adhesives for thousands of years, and the world's oldest glue on record has been carbon dated as being over 8,000 years old. Archaeologists discovered the glue in Israel in a cave near the Dead Sea. The glue was made from collagen, an animal protein, and it was used as a water-sealant, an adhesive and a protectant.
Four thousand years ago, ancient Egyptians used similar collagen-based glues in furniture construction, and about 1,500 years ago, Native American people used collagen-based glues while making bows for hunting and batlle.Learn more about Chemistry
When you need to separate a joint that has been sealed with wood or polyvinyl acetate glue, it is sometimes possible to soften the glue. Doing this allows you to separate the two pieces of wood without causing damage to either of them. Polyurethane glue, however, is waterproof and therefore harder to soften and separate.Full Answer >
PVA glue, or polyvinyl acetate, is also known as school glue or white glue. It can be made at home with ten ounces of water, three tablespoons white flour and one tablespoon of sugar.Full Answer >
Strong, flexible glues, specifically adhesives containing vinyl acetate or rubber cement, are best when working with leather. Vinyl adhesive is most effective due to its versatility. It can be applied easily with a brush, thinned with water and dries clear.Full Answer >
The strongest glues for plastics actually work in two ways, either by forming a bond at the joints or by melding the two plastic surfaces together. Glues that form a bond are known as reactive glues and come in two combinable components that adhere to the two plastic surfaces and form a bond without damaging the plastic. The glues that meld together plastic pieces are known as non-reactive glues. They melt a layer of the plastic's surface to form bonds.Full Answer >