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George Washington Carver wanted to improve the lives of the African American by teaching them how to be better farmers and how to use materials that they had. He believed that in order to raise the standard of living of the poor Southern farmer, he had to find ways of making the crops more valuable. To do this he spent his time in the laboratory studying every part of a plant and then determining, through chemical analyses, how to use the matter in plants for new applications.
In many cultures today, people make use of fibers from plants to make paper. These specialty papers are often sold as attractive stationary for export. Let's see if you can make some paper with fibers you might have!
Materials Required
• Potato and grater, or liquid starch
• Sock or cloth
• Larger plastic dish, cup or pan
• Water source
• Shredded, soaked newspaper
Procedure*
In this exploration, students experiment with making their own paper by using shredded, recycled paper as well as fibers from plants. The process is simple, but somewhat messy. The exploration can begin with students extracting their own starch from potato or skipping directly to making paper using liquid starch at Step #4
1. Grate a potato onto some wax paper or pan. Put the potato gratings inside an old clean sock.
3) Squeeze the sock and dip it into a dish, large cup or pan of water, Repeat the process of squeezing and dunking until the water appears cloudy. Be sure to repeat the process until the water is cloudy. Set your potato starch water aside for now.
4) Take a small portion of window screening material (4” by 4” more or less) and tape the edges all around so that the screening material will not fray.
5) Mix the shredded newspapers with the starchy water. You can use the starch from the potato or from liquid starch.For best results, this mix should be blended for a short time to reduce the old paper into individual fibers. You can use an old mixer to shred the paper. It helps if the newspapers have been soaked for a few hours.
6) Pour the blended paper/water/starch mix into a shallow pan. Students can then slide their screen into the pan to get fibers on top of the screen.
4) Spread the mixture with the back of a spoon onto the screening material so that a fine layer is formed. Add more material as needed to form enough thickness that will eventually be paper.
5) Now that the fibers are on the screen, place the screen on a flat surface with a paper towel under it and a piece of wax paper on top. Put a book or block of wood on top of the wax paper to press the excess water from the screen. Remove book and wax paper and allow the screen and mixture to air dry for several hours. A lamp or sunny place can speed up this process.
6) When dry, peel the dried “Paper” from the screen. The texture, color, thickness of the paper are all dependent on the kind of materials used.
*(An alternative photo tutorial of the process can be found at http://www.wikihow.com/Make-Paper-at-Home)
Extension
1) What other fibers could be utilized to make paper? Have students brainstorm what they know of crops and vegetable products. Just about any dried plant could be explored as a potential source for fibers for paper making. Carver used peanut hulls. If there are no peanut allergies, have students examine peanut hulls and tell how they would attempt to make paper from this fiber.
2) Allow students an open exploration to create various paper experiments using a variety of fiber sources that they find.
Have students brainstorm the utility of their recycled paper. Consider the energy used in the manufacture of new paper and the benefits of recycling. See the following website for information about recycling:
http://www.tappi.org/paperu/all_about_paper/earth_answers/Recycle1.htm
Discussion
The fibrous parts of plants are made of cells that have rigid walls. These walls are made most often of cellulose. Cellulose is a complex carbohydrate that is stacked together to make fibers in woody materials.
See more at:http://dennisliu-biology.blogspot.com/2011/02/macromolecules-carbohydrates.html
Cellulose is not digested by humans. It can be used as fuel such as wood or can be composted for fodder or farming. Another use of cellulose is in the manufacture of paper.
Paper
When wood or woody material is broken down, fibers of cellulose are released. In paper production, fibers are mechanically and chemically reduced in size. Starch is added to these fibers and then the fibers are usually bleached white with harsh chemicals such as chlorine. The mixture is spread over fine mesh screens and squeezed to remove excess water. A complete process can be seen at:
http://www.forestprod.org/cdromdemo/pf/pf8.html
Eco-friendly Paper Production
Recycled paper often has interesting blemishes and may be gray-colored because it can contain the ink, paper and other unknown contaminants found in a stack of old recycled newspapers. Some recycled paper companies add bleach to their “stews” to decolorize the gray mix. Paper making is a more toxic process if bleaching is involved as there are always issues surrounding where and what happens to the paper-making liquids after they are used.
Some third-world micro businesses specialize in creating recycled paper products. Shown below are steps taken by a home business cooperative in Ecuador.
The women gather recycled paper from businesses in the downtown area. Since the paper is already shredded for security reasons they can skip a step.
The paper is soaked, combined with liquid starch, and then mixed in a large bowl. The pulp is lifted out of the bowl on a fine screen in a wooden frame. The mixture is a suspension of solid material in water that will slowly fall out and drop to the bottom if it is not agitated. To remove particles from a suspension, a mechanical screening or filtration is used.
The screen and pulp are pressed to remove as much water as possible then removed and hung to dry.
Dried flower, leaves or other materials are added to the paper to add aesthetic value.
Starch
Starch is used in the eco-friendly method of paper making to stiffen and glue the fibers of cellulose together. Starch is a food stuff that is generally manufactured by plants. Plants take in sunlight and carbon dioxide. Through photosynthesis, they make simple sugars. In order to store these sugars so that they can use them in times of need, they link the sugars together to form starches. If we look at the structure of a starch, we will see that it is really a long chain of sugars.
Starches are hundreds or thousands of glucose (sugar) molecules stacked end-to-end.
Plants can alter the way molecules are constructed through changing the linkage of glucose. If plants arrange glucose in a particular fashion they can create cellulose, or plant fiber. These bonds are so tightly locked that humans can’t break them in our digestive tracks. Although we consume cellulose fiber in our diets, it remains undigested as it passes through the digestive system. Animals like cows can digest cellulose, but only after a great deal of digestion and re-digestion. One of the reasons cows have four stomachs is so that they can thoroughly digest cellulose.
Starch molecules are embedded in a variety of plants such as potatoes, carrots, and other roots and tubers. Plants store starches in their cells to provide energy as the plant starts to re-grow in the spring.
Potato starch is a complex carbohydrate that forms tiny grains when dried. When dampened and agitated, the grains can be partially lifted into water. When the starch is dried again, the grains form and “tighten” the structure. Starch on cloth, for example, stiffens the fabric. When agitated in water, the starch is held in “suspension” in the water. Materials in suspension are only there temporally and will fall to the bottom when the water is allowed to quiet. Suspensions are different from colloids and solutions.
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