How is paper made? Chemistry Calendar, April: Industry

Uploaded by MoleCluesTV on 04.04.2011


Take a look at this.
About 75% of our country is covered by forests.
And did you know that Sweden is one of the largest exporters
of forest-based products in the world?
And one of the most important products
from this forest industry is this...
But why is it that the many forms of paper can be so different?
You have soft toilet paper,
slick computer paper,
and paper that can hold liquids.
And all these come from trees, just like this.
Well, the chemical stories that surround paper and the forest industry are long,
and they start right here.

Now, let’s take a closer look at the tree.

The cells in the tree have something called cellulose in their cell walls.
And cellulose are long and rigid molecules
that give the trees structural support.
The cellulose molecules are then held together by lignin
that works like a glue.
Kind of what we use when we build something tall,
we have a framework held together by cement.
And this cellulose, is also our base for making paper.
Alright, let’s go and check this out!

We’re heading to EKA Chemicals
where research is done on cellulose to give paper different properties.
The process of making paper starts with the pulp.
So in these buckets we have paper pulp.
This is where we end up before we dry it to make the actual paper.
Well, let’s not skip any steps.
How did the tree end up here?
Okay, here it goes.
The trees are first cut to woodchips,
then boiled to remove most of the lignin,
the remaining cellulose is then made into liquid paper pulp,
which is dried and then sent to be made into paper.
We have 99.5% of water in here.
So the reason why this is so diluted at this stage is you want to make sure that
the cellulose fibers are evenly spread out so you get a fine even piece of paper.
And now at this stage we can add different chemicals to the pulp
to give the final paper its special properties.
For example,
do you know what the difference is between toilet paper and paper towels?

I was just told that we shouldn’t use paper towels in the restroom, right?
So now we are going to get a little demonstration of why.
Now I will just put a ceramic ball on top here.
I add some water, about 10 ml.
No strength when you add water.
And the other soft paper…
No way!
So when making paper towels, chemicals are added to the pulp
to give the cellulose fibers wet strength,
or an ability not to break down as easily when wet.
So that is why we shouldn’t flush paper towels down the toilet,
they simply won’t break downas easily as toilet paper.
And the same goes for other types of paper.
Special chemicals give them special properties.
So here’s different softness of paper.
This is a paper towel, it’s pretty soft.
This one is a tissue, it’s even softer.
And this pink one is the softest one.
It’s toilet paper for Italian people.

So we’ve seen how trees can be made into this.
But I think you’ll be surprised
when you hear about some of the other things researchers have used wood for.
One property that researchers at Chalmers University of Technology are looking at,
is the ability of cellulose to absorb water.
So soon our children may be walking around with diapers made completely out of wood.

And what about food?
Well eating cellulose is hard,
and animals usually need a special digestive system.
But we have found uses for it,
in for example the protective coating of salami.
Completely edible and biodegradable!
And scientists have also combined cellulose with a biodegradable corn product
to give the material plastic-like properties.

So we’ve learned that the industry behind this
is something that affects us all.
And chemistry is the key to discovering new ways to use cellulose.
And the good thing here is,
once one tree is taken down, you can plant another one!
And remember,
Chemistry is all around You!