Bakelite

From Wikipedia, the free encyclopedia

Jump to: navigation, search
 This article may require cleanup to meet Wikipedia's quality standards. Please improve this article if you can. (February 2007)
Bakelite letter opener from around 1920

Bakelite (pronounced /ˈbеɪkɨlaɪt/) is a material based on the thermosetting phenol formaldehyde resin polyoxybenzylmethylenglycolanhydride, developed in 1907–1909 by Belgian Dr. Leo Baekeland. Formed by the reaction under heat and pressure of phenol (a toxic, colourless crystalline solid) and formaldehyde (a simple organic compound), generally with a wood flour filler, it was the first plastic made from synthetic components. It was used for its electrically nonconductive and heat-resistant properties in radio and telephone casings and electrical insulators, and was also used in such diverse products as kitchenware, jewellery, pipe stems, and children's toys. In 1993 Bakelite was designated an ACS National Historical Chemical Landmark in recognition of its significance as the world's first synthetic plastic.[1]

The retro appeal of old Bakelite products and labor intensive manufacturing has made them quite collectible in recent years.

Contents

[edit] History

The Bakelite Corporation was formed in 1922 after patent litigation favorable to Baekeland from a merger of three companies: the General Bakelite Company, which Baekeland had founded in 1910, the Condensite Company founded by J.W. Aylesworth, and the Redmanol Chemical Products Company founded by L.V. Redman.[2]

Structure of Bakelite

The American Catalin Corporation acquired the Bakelite formulas in 1927 and currently manufactures Bakelite cast resins.

Bakelite Limited was formed in 1926 from the amalgamation of three suppliers of phenol formaldehyde materials: the Damard Lacquer Company Limited of Birmingham; Mouldensite Limited of Darley Dale and Redmanol Chemical Products Company of London. Around 1928 a new factory opened in Tyseley, Birmingham, England (subsequently demolished in 1998). In 1939 the company was acquired by the Union Carbide and Carbon Corporation.

[edit] Properties

Phenolics are seldom used in general consumer products today due to the cost and complexity of production and their brittle nature. An exception to the overall decline is the use in small precision-shaped components where their specific properties are required, such as moulded disc brake cylinders, saucepan handles, electrical plugs and switches and electrical iron parts. Today, Bakelite is manufactured and produced in the form of sheets, rods and tubes for hundreds of industrial applications in the electronics, power generation and aerospace industries, and under a variety of commercial brand names, including Garolite.

Bakelite distributor rotor.

Phenolic sheet is a hard, dense material made by applying heat and pressure to layers of paper or glass cloth impregnated with synthetic resin. These layers of laminations are usually of cellulose paper, cotton fabrics, synthetic yarn fabrics, glass fabrics or unwoven fabrics. When heat and pressure are applied to the layers, a chemical reaction (polymerization) transforms the layers into a high-pressure thermosetting industrial laminated plastic. When rubbed, original Bakelite has a telltale odor.

Bakelite Phenolic is produced in dozens of commercial grades and with various additives to meet diverse mechanical, electrical and thermal requirements. Some common types include:

  • PAPER REINFORCED PHENOLIC NEMA XX per MIL-I-24768 PBG Normal electrical applications, moderate mechanical strength, continuous operating temperature of 250°F.
  • CANVAS REINFORCED PHENOLIC NEMA C per MIL-I-24768 TYPE FBM NEMA CE per MIL-I-24768 TYPE FBG Good mechanical and impact strength with continuous operating temperature of 250°F.
  • LINEN REINFORCED PHENOLIC NEMA L per MIL-I-24768 TYPE FBI NEMA LE per MIL-I-24768 TYPE FEI Good mechanical and electrical strength. Recommended for intricate high strength parts. Continuous operating temperature 250°F.
  • NYLON REINFORCED PHENOLIC NEMA N-1 per MIL-I-24768 TYPE NPG Superior electrical properties under humid conditions, fungus resistant, continuous operating temperature of 160°F.

[edit] Patents and Trademarks

(After following the patent link, click on the "Images" button to view the patent. You will need a TIFF (.tif) viewer to view the patent.)

Bakelite AG (a German company) claims to own the trademark in the following countries: Argentina, Australia, Austria, Bangladesh, Belgium, China, Cuba, Czech Republic, Egypt, France, Germany, Greece, Hungary, India, Ireland, Israel, Italy, Liechtenstein, Luxembourg, Republic of Macedonia, Malaysia, Morocco, the Netherlands, New Zealand, Norway, Pakistan, Switzerland, Singapore, Slovakia, South Africa, Spain, Sri Lanka, Taiwan, Thailand, Tunisia, and the United Kingdom.[3]

[edit] Applications and usage

Bakelite radio at Bakelite museum.

Although no longer extensively used as an industrial manufacturing material, Bakelite was used in myriad applications including saxophone mouthpieces,whistles, cameras, solid-body electric guitars, rotary-dial telephones, early machine guns, and appliance casings. Recording cylinders produced by the Edison Electric Company (now General Electric) and 78-rpm phonograph records were originally made of Bakelite. The thermosetting plastic was at one point considered for the manufacture of coins, due to a shortage of traditional manufacturing material. In 1943, Bakelite and other non-metal materials were tested for usage as a penny in the United States before the Mint settled on zinc coated steel.[4][5]

The foremost usage of Bakelite today is as a substitute for porcelain and other opaque ceramics in applications where fine detail is unimportant (other thermoset resins can capture detail more finely when molded) and durability over traditional ceramic compounds is desired. As such, a main continuing use for bakelite is in the area of board and tabletop games. Devices such as billiard balls, dominoes, Mahjongg tiles and other gaming tilesets, and movers/pieces for games like chess, checkers, and backgammon are constructed of Bakelite for the look, durability, fine polish, weight, and sound of the resulting pieces. Dice are sometimes made of Bakelite for weight and sound, but the majority are made of a thermoplastic such as ABS. It is also used to make the presentation boxes of luxury Breitling watches. Bakelite is also sometimes used as a substitute for metal in the construction of firearm magazines.

Bakelite is also used in the mounting of metal samples in metallography[6].

[edit] See also

[edit] References

  1. ^ New Products
  2. ^ American Institute of Chemical Engineers Staff (1977). Twenty-Five Years of Chemical Engineering Progress. Ayer Publishing. pp. 216. ISBN 0836901495. 
  3. ^ "Our reference - Protection of brands". Bakelite AG. June 18, 2007. http://www.bakelite.de/eng/DF_04.htm. 
  4. ^ J2051/P2073 USPatterns.com. Accessed July 28, 2006
  5. ^ The New Yorker. Penny Dreadful. David Owen. March 31, 2008.
  6. ^ http://www.grc.nasa.gov/WWW/StructuresMaterials/ASG/MetLab/mounting.html

[edit] External links

Retrieved from "http://en.wikipedia.org/wiki/Bakelite"
Personal tools