Material Science: Plastics, Textiles, Ceramics, and Stone

Material Science: An Overview

Plastics are classified as:

Thermoplastics: Obtained from oil-derived compounds, they soften when heated.
Thermosets: Formed by chains linked strongly in different directions, they become rigid and can only be heated once.
Elastomers: Obtained by vulcanization (invented by Charles Goodyear), they consist of chains attached laterally and folded back on themselves.

Common co-formation techniques used include:

Extrusion: Thermoplastic material in granule form is introduced through a funnel or hopper into a heated cylinder. A large spindle moves the molten material, which is then formed, cooled, and collected slowly.
Calendering: Thermoplastic material, often from an extrusion process, is passed through calenders with different surfaces to achieve various finishes.
Vacuum Forming: The thermoplastic material is subjected to a heated plate. A radiator softens the material, and air is sucked from under the sheet, creating a vacuum that forms the desired shape. Once cooled, the mold is opened.
Casting:
- Blow Molding: Material in tube form is inserted into a hollow mold. Compressed air is injected inside the tube to take the mold’s shape. The object is then removed.
- Injection Molding: Thermoplastic material is injected into a mold, cooled, and then removed.

Textiles are classified as:

Natural: Materials extracted from raw vegetable, animal, or mineral sources. The fibers are cleaned, melted, stretched, stained, and twisted to form threads of different lengths for fabric manufacture.
Synthetic: Plastic materials characterized by their great length. Textile fiber manufacture often uses a mixture of natural and synthetic fibers.

Ceramics are classified as:

Thick Ceramics: Cooked clay, often covered with a white enamel (e.g., brick tiles). Loza is covered by a layer of varnish or enamel, providing an attractive surface appearance (e.g., dishes, bathroom tiles). Refractories are used in lining blast furnaces.
Fine Ceramics: Stoneware is used for tiles requiring special hardness and resistance. Porcelain, with a thickness of 2mm, is used in tableware, decorative items, tiles, and sanitary ware.

Stone materials are classified as:

Natural Rocks: Marble, granite, and slate.
Binders: Gypsum, cement, mortar, and concrete.
Glass: A stone material obtained by mixing quartz sand, soda, and lime at high temperatures.

Slate is a hard, dense, and compact material, making it impermeable. It is removed in the form of slabs, primarily used for roofing.

Marble and granite are rocks characterized by high density, cold touch, hardness, and resistance to environmental conditions.