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Gluep
 This
activity is an introduction to
the branch of chemistry that dealswith
polymers. Polymers are the linked
chemicals that make up such common
materials as paper and plastic.
These linked molecules are called
polymers because they are chains
of many smaller molecular units
(monomers) linked to make larger
molecules. Polymers, both natural
and synthetic, are a very important
part of our world.
 What
You Need:
-
Elmer's® Brand glue
- Borax
- Distilled
water
- 2
large paper cups
- Eye
dropper
- Food
coloring (optional)
Safety
First!
Always:
- Work
with an adult.
- Read
and follow all directions
for the activity.
- Read
all warning labels on all
materials being used.
- Use
all materials carefully, following
the directions given.
- Be
sure to clean up and dispose
of materials properly when
you are finished with an activity.
Liquid waste can go down the
sink; solid waste may be disposed
of in the trash. Gluep can
be stored in a plastic bag
for a few days.
- Wash
your hands well after every
activity.
Never
eat or drink while conducting
an experiment, and be careful
to keep all of the materials used
away from your mouth, your nose
or your eyes!
What
You Do:
1)
Pour 1 cup distilled water into
a paper cup. Then, pour enough
Borax into the distilled water
until it will no longer dissolve.
Crystals will remain on the bottom.
This is called a "saturated"
solution.
2)
Pour some glue into the second
paper cup, filling about 1/4 of
the cup.
3)
Add 2 tablespoons of distilled
water to the glue and stir until
well mixed. You can also add food
coloring to the mixture.
4)
Add one tablespoon of the saturated
borax solution and continue to
stir until the "slimy gluep"
forms.
5)
If your "slimy gluep"
is too slimy, add a little more
borax solution.
- Roll
the gluep into a ball. Does
it maintain its shape?
- Pat
the gluep into a thin film.
Hold up the film. What happens?
- Drop
a gluep ball onto the desk.
What does it do?
- Roll
the gluep into a cylinder
and pull the ends slowly,
what happens?
- Roll
the gluep into a cylinder
and pull the ends quickly,
what happens?
What's
Happening:
The
glue contains strands of polymers,
which combine when the glue dries.
The borax connects the polymer
strands together without getting
rid of the water, which is why
the "slimy gluep" is
not hard and chunky.
Elmer's
® Brand Glue already contains
a polymer, polyvinyl acetate.
The chains of polyvinyl acetate
molecules are so long that they
interfere with each other and
cause the glue to be thick and
pour slowly. The borax acts as
a cross linker. It connects the
polyvinyl acetate chains together
to form a more solid substance,
gluep.
National Chemistry Week is October
20-26th 2002!
"Chemistry Keeps Us Clean!"
For
more information: http://chemistry.org/oca
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