Monday, November 5, 2012

Bakelite



Bakelite
From Wikipedia, the free encyclopedia


     Bakelite 
     or polyoxybenzylmethylenglycolanhydride is an early plastic. It is a thermosetting phenol formaldehyde resin, formed from an elimination reaction of phenol with formaldehyde. It was developed by Belgian-born chemist Leo Baekeland in New York in 1907.
One of the first plastics made from synthetic components, Bakelite was used for its electrical nonconductivity and heat-resistant properties in electrical insulators, radio and telephone casings, and such diverse products as kitchenware, jewelry, pipe stems, and children's toys. Bakelite was designated a National Historic Chemical Landmark in 1993 by the American Chemical Society in recognition of its significance as the world's first synthetic plastic.The "retro" appeal of old Bakelite products have made them collectible.

History

      Dr. Baekeland had originally set out to find a replacement for shellac, made from the excretion of lac beetles. Chemists had begun to recognize that many natural resins and fibers were polymers, and Baekeland investigated the reactions of phenol and formaldehyde. He first produced a soluble phenol-formaldehyde shellac called "Novolak" that never became a market success, then turned to developing a binder for asbestos which, at that time, was molded with rubber. By controlling the pressure and temperature applied to phenol and formaldehyde, he produced a hard moldable material and patented in 1907 known as Bakelite. It was the very first synthetic thermosetting plastic ever made. It was often referred to as "the material of 1000 uses", a phrase originated by Baekeland himself.
      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 founded in 1910, the Condensite Company, founded by J.W. Aylesworth, and the Redmanol Chemical Products Company, founded by L.V. Redman. A factory was built near Bound Brook, New Jersey in 1929.
      In 1939 the companies were acquired by Union Carbide and Carbon Corporation. Union Carbide's phenol resin business including the Bakelite and Bakelit registered trademarks are owned by Momentive Specialty Chemicals. Today, Bakelite is manufactured and produced in sheet, rod and tube form for hundreds of industrial applications in the electronics, power generation and aerospace industries, and under a variety of commercial brand names.
      Phenol 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 tell-tale odor.

Applications and usage

Bakelite radio

      In its industrial applications, Bakelite was particularly suitable for the emerging electrical and automobile industries because of its extraordinarily high resistance - not only to electricity, but to heat and chemical action. It was soon used for all nonconducting parts of radios and other electrical devices, such as bases and sockets for light bulbs and vacuum tubes, supports for electrical components, automobile distributor caps and other insulators.
      In the early 20th Century, it was found in myriad applications including saxophone mouthpieces, whistles, cameras, solid-body electric guitars, telephone housings and handsets, early machine guns, pistol grips, and appliance casings. In the pure form it was made into such articles as pipe stems, buttons, etc. Bakelite is used today for wire insulation, brake pads and related automotive components, and industrial electrical-related applications. The thermosetting phenol resin was at one point considered for the manufacture of coins, due to a shortage of traditional material; in 1943, Bakelite and other non-metal materials were tested for usage for the one cent coin in the US before the Mint settled on zinc-coated steel.
      After the Second World War, factories were retrofitted to produce Bakelite using a more efficient extrusion process which increased production and enabled the uses of Bakelite to extend into other genres: jewelry boxes, desk sets, clocks, radios, game pieces like chessmen, poker chips, billiard balls and Mah Jong sets. Kitchenware such as canisters and tableware were also made of Bakelite through the 1950s.
Bakelite Tableware Set

      The primary commercial uses for Bakelite today remain in the area of inexpensive board and tabletop games produced in China, India and Hong Kong. Items such as billiard balls, dominoes and pieces for games like chess, checkers, and backgammon are constructed of Bakelite for its look, durability, fine polish, weight, and sound.