 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 | ||
Plant fibers are separated either mechanically — by pounding the plant material — or chemically — by soaking the plant material in a chemical bath. In practice, a combination of mechanical and chemical pulping is often used. Mechanical Pulping Plant material or wood chips are ground up and mixed with hot water and steam. The heat softens the lignin, and grinding pulls the fibers apart. This damages the fibers and makes them shorter and weaker, so paper made this way is not strong. Mechanical pulping does not remove parts of the plant which are not cellulose (or other impurities), so this method is usually used for newspaper and telephone directories. | ||
|
Major funding for Rough Science was provided by the National Science Foundation. Corporate funding was provided by Subaru. Copyright © 2002 The Open University and WETA. |
How
is the plant material prepared for paper making?