Man's physical universe



of the extent to which the cellulose molecules are transformed in the

manufacturing processes involved.

1. Cellulose in Slightly Altered Form. The use of cellulose in the

form of lumber, textiles, and paper involves little more than certain

physical processes such as carving, spinning, and weaving. As lumber

becomes scarce, however, it is to be expected that many lumber substitutes

will be devised which will use less wood and utilize waste

products. Such developments as plywood come under this class. Sawdust,

cork, sugar cane refuse, etc. are now used to prepare various types

of composition boards.

Mercerized cotton is an example of a slightly altered form of cellulose.

In 1844 John Mercer discovered that cotton fibers can be shortened

and strengthened by passing them through a cold solution of lye.

Later it was found that these fibers would change into smooth, silklike

tubes by stretching them during the drying process; thus mercerized

cotton came into use.

Paper is made from wood, old papers, or rags. Much of the wood

used for paper receives no chemical treatment at all but is merely

ground to a fine pulp. Higher-grade pulp must be produced by a

chemical process that will remove the lignin, i.e., noncellulosic part of

the wood. In the sulfite process, lignin is removed by heating wood

chips in a closed vessel with calcium bisulfite. Lye and sodium sulfate

are used for this purpose in other processes. The paper itself is composed

chiefly of unaltered cellulose. The paper industry produced

nearly two billion dollars' worth of products in 1939.

"Pervel" is a new fabric, unique in that it is produced by simply

pressing cellulose fibers, such as is done in paper manufacture, and

yet has the properties of cloth. It may be made to sell for but little

more than it costs to launder cotton fabrics. "Pervel" aprons, curtains,

table and bed linen, handkerchiefs, and many other products are

now available for use on the "throw away" principle.

Parchment paper resembles mercerized cotton in that the surface is

partially dissolved by sulfuric acid and is then allowed to dry. In

parchment paper the fibers are bound together to the extent that the

paper can be used as a dishrag without disintegration. Foods may be

tied up in parchment paper and cooked, thus preventing loss of flavors,

natural juices, and water-soluble substances, such as minerals, sugars,

and vitamins.

Vulcanized fiber partially resembles parchment paper. It is produced

by running paper through a solution of zinc chloride, which

produces a gelatinous hydrated cellulose on the surface. The paper is

then washed to remove zinc salts, wound in rolls, and pressed to pro-

More magazines by this user
Similar magazines