Plastics are excellent materials with unique and very useful
properties. You can produce just about anything you can imagine using
plastics.
Characteristics of Plastics
History Of Plastics:
1. Before Plastics—Age of the Natural Resins
2. Bakelite—The First True Synthetic Plastics
3. Industrialization of Major Plastics
5. Nylon—The First Tailor-Made Plastics
Characteristics of Plastics
History Of Plastics:
1. Before Plastics—Age of the Natural Resins
- Rubber—Tough elastic substance (light cream or dark amber
- colored) from the milky juice (sap) of rubber tree
- Ebonite—Hard black rubber; natural rubber + sulfur
- Gutta-Percha—Dark brown substance like natural rubber
- Shellac—dark-brown material from lac insects
- Leo Hendrik Baekeland invented Bakelite from coal
- Bakelite helped make 20th century “The Age of Electricity”
3. Industrialization of Major Plastics
| Year | Type of plastics | Note |
| 1872 | Celluloid (Hyatt, USA) | Semi-synthetic |
| 1910 | Phenolic resin, “Bakelite” (Baekeland, USA) | From coal |
| 1931 | Polymethyl methacrylate (PMMA) (Rohm and Haas, Ger-many) | From coal |
| 1935 | Polyvinyl chloride (PVC) (IG Farben, Germany) | From coal |
| 1935 | Polystyrene (IG Farben, Germany) | From oil |
| 1938 | Nylon 6 (IG Farben, Germany) | |
| 1939 | Nylon 66 (DuPont, USA) | From coal |
| 1939 | High-pressure low-density polyethylene (LDPE) (ICI, Eng-land) | |
| 1953 | Polyethylene terephthalate (PET) (DuPont, USA) | |
| 1953 | Low-pressure high-density polyethylene (HDPE) (Montecatini, Italy) | Ziegler catalyst |
| 1955 | Medium-pressure high-density polyethylene (HDPE) (Phillips, USA) | Phillips catalyst |
| 1957 | Low-pressure high-density polyethylene (HDPE) (Hoechst, Germany) | Ziegler catalyst |
| 1959 | Polypropylene (Montecatini, Italy) | |
| 1977 | Linear low-density polyethylene (LLDPE) (UCC, USA) | |
| 1991 | Metallocene very-low-density polyethylene (VLDPE) (Exxon, USA) | Metallocene cata-lyst |
4. Concept of High Molecular Weight Compounds & Polymers
- Herman Staudinger, German chemist, proposed a new theory that several thousands of reactive units bonded together in chains and form giant molecules to make up cellulose and rubber
- In 1920, Staudinger proposed calling such materials: high molecular weight compounds, macromolecules, or polymers.
- 1931 – Fiber 66 was produced, later called Nylon 66 in 1938
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