The MGA With An Attitude
PLASTICS Used In MGA -- UT-111

May be used in MGA for cut down Sport Windscreen and rigid panes in side curtains.

Acrylic (short for acrylic glass) and Polycarbonate (short for polycarbonate resin thermoplastic glass) are two different materials. Acrylic (often called Plexiglas®) has higher tensile strength, is slightly stiffer, less likely to scratch, is less prone to yellowing with exposure to ultraviolet (sun light). Polycarbonate (sometimes called Lexan®) is tougher with better impact and chip resistance (bulletproof when thick enough), and is 2 to 3 times more expensive. Either material may be treated with special surface treatment to improve scratch resistance, sometimes used for bearing loads. For more information on the physical properties of the two materials, see

Registered Trade Names
    for Acrylic (Acrylic glass):
ICI Acrylics 1930's, DuPont Lucite 1930's, Lucite International 2002, Mitsubishi Rayon 2009
Lucite® (in USA), or Perspex® in the UK
Altuglas® Altuglas International (see Plexiglas)
Plexiglas® Rohm and Haas Company 1933, Röhm GmbH Co, Atoglas, Altuglas International (subs. of Arkema Group
Altuglas® in Asia/Pacific, Europe, Africa and the Middle East, or
Plexiglas® in North and Latin America

    for Polycarbonate (Polycarbonate resin thermoplastic glass):
Atoglas® Atofina
Lexan® GE Plastics Corp, SABIC Innovative Plastics
Makrolon® Bayer AG (Bayer and Bayer MaterialScience LLC)
Tuffak® Atofina

This stuff is a little trickier in how it got its name.
1.- A substance obtained from the dried swim bladders of fish, it is a form of collagen with uses in the food industry, making glue, restoring old paintings. In natural form it is a clear substance. It is not used in the MGA.

2.- More properly known as muscovite, this isinglass is a form of mica that is often found in sheets. The sheets are often very thin, transparent, and somewhat elastic in nature. It was called Isinglass because it is clear (like the prior definition). This mineral can be found in a number of different natural formations, including granites and gneisses. Thin transparent sheets of mica were used for peepholes in boilers, lanterns, stoves, and kerosene heaters because they were less likely to shatter than glass when exposed to extreme temperature gradients. Such peepholes were also used in "isinglass curtains" in horse-drawn carriages and early 20th century cars, but the peepholes were not flexible, and this is also not used in MGA.

3.- Celluloid is a transparent form of polyvinylchloride, more commonly referred to as vinyl. It is resistant to corrosion and chemicals and was flame-resistant as well. This was commercially available in the 1920's. It could be as rigid as pipe or as pliable as plastic wrap and is much lighter than metal or glass. It is also resistant to rot and mold and corrosion and chemicals and is flame-resistant as well. One of the early applications of celluloid was for light weight flexible side curtains in the Ford Model T. This was also called Isinglass because it is flexible and transparent, and now we have the origin of the word Isinglass as used in automobiles. This is the material used in the rear windows of the MGA convertible top, and for all clear panels in the original style MGA 1500 side curtains, and the forward fixed panels of the MGA 1600 side curtains. You can call it cellulose or PVC or vinyl, but for flexible transparent panels in we still call it Isenglass (even though other non-transparent PVC parts are called vinyl).

BAKELITE®: (Phenolic)
Polyoxybenzylmethylenglycolanhydride -- Say that just once fast. Need help?

Bakelite is made from phenolic resin (below) and wood flour. It was the world's first synthetic plastic, a thermosetting phenol formaldehyde resin, developed by Belgian-born chemist Leo Baekeland in New York in 1907. Commonly artificially colored black, it can be made in a rain bow variety of dark colors, it can be molded into almost any possible shape, and along with Phenolic it became the jewelry of the Art Deco age. When reinforced with asbestos it is phenol-fiber. In more recent years the strengthening fiber could be paper or glass cloth, cellulose paper, cotton fabrics, synthetic yarn fabrics, glass fabrics or unwoven fabrics. In automotive use it is the hard plastic material used for dash knobs, gearshift knobs, steering wheels, and possibly brake pads (in low temperature applications). In the MGA it is also used for the heater control panel, spark plug connectors, distributor cap and rotor, electrical control box and cover, fuse block, starter switch (original issue), and the turn signal vacuum delay switch.

Patent #942,699 December 7, 1909, expired in 1927, but the Bakelite registered trademark still persists. General Bakelite Company 1910, Bakelite Corporation 1922, Bakelite Limited 1926, acquired by Union Carbide 1939, Bakelite AG (late 1980's), Borden Chemicals 2004, Hexion Specialty Chemicals 2005, merged with Momentive Performance Materials 2010.

Bakelite® 1909, commonly refers to molded products.
Catlin® 1927, commonly refers to cast products, began when the original patent expired.

Phenol formaldehyde resins (PF), functionally similar to Bakelite. Where Bakelite could be made only in dark colors, Phenolic can be made in almost any color under the sun.

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