2. HOW DOES GLUE WORK?
Did you ever wonder how glue works?
Glue is an adhesive. Do you know what an adhesive is?
To understand adhesives, you must first understand
polymers.
Although there are many ingredients used to make
glue, most formulas contain polymers. A polymer is a
large strand of molecules much like spaghetti.
3. HOW DOES GLUE WORK?
One of the ingredients that make up glue is a polymer,
which is derived from two Greek words.
Small parts (called monomers) form a larger chain called a
polymer which is used in glue. As the glue dries, the
polymer hardens and provides a bond.
The word polus means many and the word meros means
parts. Polymer means “many parts.”
4. POLYMERS
There are lots different
types of polymers,
including glue, plastic,
rubber, Jell-O, camera film,
materials such as nylon,
and even natural fibers
from wood and cotton.
5. THE DISCOVERY OF GLUE
The first adhesive was discovered around
1750. It was made from fish. Other
scientists began to make glues
from rubber, animal bones, fish, starch,
milk protein and casein.
Original white glue was introduced by
Borden's in 1947. It was named "Elmer's"
after the spouse of Borden's famed dairy
mascot, Elsie. Elmer’s first glue was
made from a polymer found in milk called
casein.
6. WHY DOESN’T GLUE STICK TO THE BOTTLE?
As long as the glue remains inside the
bottle away from air, it will remain fluid.
Glue hardens when there is a loss of
water from the formula. Exposure to the
atmosphere will cause the water to
evaporate and make the glue harden.
That's why it is important to keep the cap
on the glue bottle closed to prevent
hardening or drying out.
7. GLUES AND OTHER ADHESIVES
Krazy Glue is a substance called cyanoacrylate. It
was discovered by Dr. Harry Coover while working
for Kodak Research Laboratories to develop clear
plastic gunsights in 1942. But it was too sticky for
the gun sights.
About 10 years later, Coover rediscovered
cyanoacrylate when he was looking for a heat-
resistant, fast-drying substance that would work for
jet canopies. Cyanoacrylate consists of monomers
that bond together into polymers when applied to
surfaces.
8. ADHESION AND COHESION
An adhesive is a substance that is capable of holding
materials together by surface attachment.
9. GLUES AND OTHER ADHESIVES
Every day, we
experience adhesives
all around us.
How many other
examples can you
think of?
