Where does paper come from?
(Student Activity #4, Appendix D)
Most paper comes from the cellulose in trees; some paper comes from linen, cotton or other plants. Cellulose is a natural polymer. It consists of fibers glued together with another natural polymer, called lignin. The monomer in the polymer cellulose is: aldohexose D-glucose, which is represented by: C 6H 1 2O 6 and changes into the polymer cellulose which is represented by: (C 6H 1 0O 5) n ,plus water, H 2O. Again, the n stands for the repeating of the monomer in the polymer. In fact, the chain of the polymer, cellulose, can consist of several hundred to over 10,000 repeating units. Trees also have another polymer, lignin, which holds the cellulose together and has been compared to an early thermoplastic polymer, Bakelite. The lignin is chemically washed away from the cellulose to make paper. 8
To make high quality paper, the cellulose from both hard and soft wood trees is used. Hard wood trees have longer fibers and the soft wood trees have shorter fibers. In the processing of paper, the wood is ground into pulp, the lignin is removed by washing and chemicals, the water is pressed out and the paper is dried. Paper is often bleached and filled with clay and calcium carbonate. Then high quality paper is usually coated with paint-like substances to give color and sheen. 8 Paper demand has increased 400% in the last 40 years and 30% in the last 6 years. It is projected to increase even more. The EPA has disclosed that paper mills are some of the worst polluters of air, water, and land. They release toxic chemicals into air and land, including: toluene, methanol, chlorine dioxide, hydrochloric acid, and formaldehyde. 8 Most of the trees used for paper come from tree farms and which are regularly replanted, and thus renewable. However, it was noted that with the growing demand for paper, the soft wood trees cut for paper have begun to outnumber the growth of new trees. 9
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