The science idea
Every year a great deal of paper is thrown away: newspapers, notebooks, packing, school papers. Most of it can be recycled, and you can see how by making a few sheets of your own. The process you will use is the oldest method of papermaking, used for hundreds of years before factories, and it is a perfect best-out-of-waste project.
Paper is made of cellulose fibres, long thin threads that come from the cell walls of plants, usually from wood, but also from cotton, bamboo, bagasse (sugarcane waste) and straw. Cellulose is a natural polymer, a very long molecule made of many glucose units joined together. When paper is soaked in water the fibres swell and the bonds between them loosen. Beating, mashing or blending separates the fibres completely and makes a thin soup called pulp.
To make a new sheet, the fibres are suspended in water and a fine mesh is dipped in the pulp and lifted out. The water drains away through the mesh, but the fibres are too big to pass through and are left behind as a thin, wet mat with the fibres lying in random directions. As the sheet dries, water leaves the spaces between fibres and the fibres are pulled tightly against each other. Cellulose has many hydroxyl (OH) groups, and at the places where two fibres touch, these form hydrogen bonds, which hold the fibres together. That is why dry paper is strong, but wet paper is weak and falls apart: water breaks the hydrogen bonds.
Every time paper is recycled, the fibres are cut a little shorter and become weaker, so paper can be recycled only a limited number of times, often about five to seven times, before the fibres are too short. Recycling still saves trees, water and energy compared with making all the paper from new wood, and it keeps waste out of landfills. Your homemade paper will be thicker and rougher than factory paper, and that is normal.
You can test your paper like a scientist. Weigh and measure it to find its grammage (grams per square metre, the usual way of describing paper weight), measure how much load a strip can hold before it tears, and see how a drop of ink spreads. A little starch, called sizing, fills the gaps between the fibres and makes ink spread less.
Materials and tools
Cost: Free
Waste paper, an old net, card and cloth are free. If you have no mesh you can buy a small piece of net or mosquito mesh for a few rupees.
| What you need | How many | Free substitute or where to find it |
|---|---|---|
| Waste paper: newspaper, used copy pages, paper bags, egg cartons | About 2 handfuls (a few sheets of newspaper) | Collected from the house. Do not use glossy, waxed, plastic-coated or very heavily printed paper. |
| Two wooden or card frames 20 cm × 15 cm, each with strips 2 cm wide | 2 | Cut from stiff cardboard (glue 3 layers together) or old wooden picture frames or the sides of a wooden box. |
| Mesh: mosquito net, nylon net or an old window screen | 1 piece, 25 cm × 20 cm | From an old mosquito net or a net curtain. It should have small, even holes. |
| A big tub or plastic tray, deeper and larger than the frames | 1 | A washing-up tub or a basin. |
| Cotton cloths or felt, a little larger than the frames | 6 pieces | Old bedsheet or T-shirt cut into squares. |
| Sponge and a rolling pin or bottle | 1 each | A kitchen sponge, and a bottle to roll. |
| Flour paste (sizing, optional) | 1 teaspoon of wheat flour in half a cup of water | Boil it for a minute until it thickens (adult) and cool it. |
| Staples or a strong glue, and tape | 1 stapler | From the stationery box. |
| Boards and heavy books for pressing | 2 boards, a few books | Flat pieces of ply or thick card, and school books. |
Tools
- Scissors
- Stapler and a hammer (adult for the frames)
- Kitchen blender (adult only), or a masher, a wooden spoon or your hands
- A kitchen scale (to the nearest gram, if possible) and a ruler
- A bucket for waste water
- Plastic apron or old clothes
Safety first
Read this before you start
- Only an adult should use the blender. Never put hands in the jar, and always switch it off and unplug it before you open it.
- An adult should boil the flour paste. Hot paste can scald. Let it cool before you use it.
- Do not pour pulp down the drain: it clogs the pipe. Put the leftover pulp on the garden or in the dustbin, and throw the water on the plants.
- Wet floors are slippery. Work on a tray or on a plastic sheet, and wipe up spills.
- Staples and the edge of the mesh can be sharp. Cover them with tape. Wash your hands after the work.
Parts and layout
These drawings show the parts and how they fit together. Keep them beside you while you build.
Scroll sideways to see the whole diagram.
Scroll sideways to see the whole diagram.
Step-by-step build
12 steps. Do them in order, and test each part before you go on to the next.
Collect and sort the paper
Pick plain paper: newspaper, notebook pages, brown paper bags, egg cartons. Remove staples, plastic windows and sticky labels. Keep the different kinds in separate piles.
Tip: Newspaper makes grey paper. Plain white paper gives a lighter colour. Mix them to see the effect.
Tear and soak
Tear the paper into pieces about 2 cm wide and drop them into a bowl. Cover them with warm water and leave them for at least 4 hours or overnight.
Common mistake: Skipping the soaking. Dry or half-soaked paper does not turn into smooth pulp.
Make the mould and deckle
Make two frames the same size, 20 cm × 15 cm outside and with strips 2 cm wide. Staple or glue the mesh tightly over one frame. This is the mould. The other frame, with no mesh, is the deckle.
Tip: The mesh must be tight and flat. Wrinkles make a sheet with a thick edge or a hole.
Seal the edges
Cover the staples and the edges of the mould with waterproof tape so that the cardboard does not soak up water and so that the frame does not fray.
Common mistake: Using an unprotected card frame. The card gets soggy and the frame bends.
Make the pulp
An adult blends one cup of soaked paper with three cups of water for about 20 to 30 seconds, until there are no lumps. Without a blender, mash the paper with a masher or hands and beat it with a wooden spoon for 10 minutes.
Tip: Do not blend the pulp for too long. Very short fibres give weak paper.
Fill the tub
Pour the pulp into the tub and add water so that the tub is about two thirds full. Mix in a teaspoon of flour paste (sizing) if you want a sheet you can write on. Stir well.
Common mistake: Making the pulp too thick. A good mix looks like thin porridge. Too thick gives thick, lumpy paper.
Prepare the cloths and the work area
Wet the cloths and wring them out until damp. Spread a flat cloth on the board. Have the sponge and a second board ready. Put the tub on a tray.
Tip: Folded newspapers under the cloths soak up water and make cleaning up easy.
Dip and lift
Hold the deckle on top of the mould, with the mesh facing up. Stir the pulp, then slide the pair into the tub at a slant, then level them under the pulp and lift them straight up, flat. Let the water drain for a few seconds, shaking gently.
Common mistake: Tipping the mould while lifting it. The pulp slides to one side and the sheet is thin at one end.
Remove the deckle and couch
Take off the deckle. Quickly turn the mould upside down onto the wet cloth, so that the pulp lies on the cloth. Press the back of the mesh with the sponge, soaking up the water, and then slowly lift the mould, leaving the sheet behind.
Tip: Rock the mould gently and roll it on to the cloth from one edge to the other so that air is not trapped.
Stack and press
Cover the sheet with another damp cloth. Make more sheets in the same way, stacking them cloth, sheet, cloth. Put a board on top and press the stack with heavy books or by standing on the board (an adult) so that the water squeezes out.
Common mistake: Pressing too hard at the beginning. It can tear the wet sheets. Press gently and then harder.
Peel and dry
Gently peel each sheet off its cloth and lay it on a flat clean surface, or hang it on a line with pegs, or stick it on a window glass. Leave it until it is completely dry, for about 24 hours.
Tip: A sheet dried flat between two clean cloths under a book is flatter than a sheet dried in the air.
Test your paper
Weigh a dry sheet and measure its area to find grams per square metre (mass ÷ area in cm² × 10 000). Cut a strip 2 cm wide, hang a cup from it and add small weights until it tears. Put one drop of ink on it and on a piece of newspaper and compare how they spread.
Tip: Do the strength test the same way for each paper: the same width, the same length and the same way of adding weights.
How it should look when it is finished
A few rough sheets of grey or cream paper, each about the size of a postcard, with slightly uneven edges and flecks of newsprint in them. They feel thicker and more textured than ordinary paper, and you can write on them with a pen, especially the ones made with a little flour sizing.
This is a description, not a photograph. Compare your own model with it and with the figures above.
How it works
Soaking and beating pull the old sheets apart into separate fibres of cellulose, which float in water as pulp. The mesh of the mould acts as a sieve: water runs through, but the fibres are too big to pass and are left in a layer on the mesh.
Couching transfers the wet mat onto a cloth and pressing squeezes out most of the remaining water, so the fibres are pressed together. As the last water evaporates, hydrogen bonds form where the fibres touch, and the mat becomes a strong sheet.
The flour sizing coats the fibres and fills the tiny gaps, so ink and water do not soak in so quickly and writing looks sharper.
Scroll sideways to see the whole diagram.
Troubleshooting
| What you see | Likely cause | What to do |
|---|---|---|
| The pulp is lumpy | The paper was not soaked or beaten enough. | Soak longer and blend or beat the pulp again until it is smooth. |
| The sheet has holes or thin spots | The mould was tilted or the pulp was too thin or not stirred. | Stir the pulp before each dip and lift the mould level. Add more pulp if the mixture is thin. |
| The sheet sticks to the mesh | Not enough water was sponged out. | Sponge the back of the mesh more and rock the mould as you lift it. |
| The sheet tears when peeled | It is still too wet or too thin. | Leave it to dry more on the cloth before peeling and make the next one a little thicker. |
| Ink spreads and the writing looks fuzzy | There is no sizing, so the paper acts like blotting paper. | Add a little flour paste to the pulp, or brush a thin layer of paste on the dry sheet. |
| The paper curls as it dries | It dried unevenly in the open air. | Dry it flat between cloths under a heavy book. |
Test and record
Grams per square metre = mass in g ÷ area in cm² × 10 000. For the strength test, use a strip 2 cm wide and add small weights (coins or sand in a cup) until it breaks. Record the mass hanging when it tore.
| Paper | Mass (g) | Area (cm²) | Grams per m² | Load held before tearing (g) | Ink spread (small, medium, large) |
|---|---|---|---|---|---|
| Newspaper | |||||
| Office or copy paper | |||||
| My recycled paper (no sizing) | |||||
| My recycled paper (with flour sizing) |
Copy the table into your notebook and write each reading as you take it, in pencil, with the date. Repeat every test at least three times and use the average. Then draw a graph or chart of your results.
Viva questions and answers
A teacher or a judge will ask you how your project works. Practise these eight questions and answer them in your own words.
- What is paper made of?
A mat of cellulose fibres from plants such as wood, bamboo, cotton or sugarcane waste, held together by hydrogen bonds.
- Why does the paper fall apart when it is wet?
Water gets between the fibres and breaks the hydrogen bonds that hold them together.
- What is the function of the mesh?
It lets the water drain away but catches the fibres, which form a thin wet layer.
- Why is recycled paper weaker than new paper?
Each time paper is recycled the fibres are cut shorter and are damaged, so they make fewer and weaker bonds.
- Why was starch (sizing) used?
It fills the tiny gaps between fibres, so ink does not soak in and spread, and the writing is sharper.
- Why is recycling paper good for the environment?
It saves trees, and also water and energy compared with making paper from new wood, and it reduces the waste that goes to landfills.
- What is grammage?
The mass of a paper per unit area, in grams per square metre. Copy paper is typically about 70 to 80 g/m².
- How would you make a fair comparison of paper strength?
Use strips of the same width and length, add the weight in the same way and the same size steps, and repeat the test several times.
Written report outline
Use these headings in your project file, and write each part in your own words. Add a title page, your diagrams, the precautions you took and the books or sites you used.
- Aim
- To make paper from waste paper and to compare its properties with ordinary paper.
- Apparatus
- Waste paper, two frames with mesh, a tub, cloths, a sponge, a blender or masher, boards and books, scale and ruler.
- Procedure
- Describe how you made the mould and the deckle, soaked and beat the paper, dipped and lifted the pulp, couched, pressed and dried the sheets, and how you tested them. Include the diagrams.
- Observation
- The table of mass, area, grams per square metre, load held and ink spread for each paper.
- Result
- My paper was ... g/m², held ... g before it tore, and the ink spread ... compared with newspaper and copy paper.
- Conclusion
- Waste paper can be broken into fibres and made into new paper. The fibres bond as the paper dries. Recycling saves resources, but each cycle shortens the fibres.
Take it further
- Make plantable paper by mixing a few small seeds (for example tomato or marigold) into the pulp, and dry it quickly. Plant the paper in soil and see what happens.
- Add flower petals, coloured threads or pieces of dry leaves for decoration.
- Make paper from different wastes (egg cartons, straw, banana fibre) and compare their strength.
- Find out how many times you can recycle a sheet by re-pulping it.
- Use your paper to make a notebook or greeting cards, and write about how you made it.
Free ebooks, kits and help
Free ebooks for this project
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