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Two (2) Bakelite swirl bangles. Bakelite is an early p

Currency:USD Category:Antiques Start Price:20.00 USD Estimated At:250.00 - 750.00 USD
Two (2) Bakelite swirl bangles.  Bakelite is an early p
Two (2) Bakelite swirl bangles. Bakelite is an early plastic. It is a thermosetting phenol formaldehyde resin, formed from a condensation reaction of phenol with formaldehyde. It was developed by Belgian-born chemist Leo Baekeland in New York in 1907. Making Bakelite was a multi-stage process. It began with the heating of phenol and formaldehyde in the presence of a catalyst such as hydrochloric acid, zinc chloride, or the base ammonia. This created a liquid condensation product, referred to as Bakelite A, which was soluble in alcohol, acetone, or additional phenol. Heated further, the product became partially soluble and could still be softened by heat. Sustained heating resulted in an "insoluble hard gum". However, the high temperatures required to create this tended to cause violent foaming of the mixture, which resulted in the cooled material being porous and breakable. Baekeland's innovative step was to put his "last condensation product" into an egg-shaped "Bakelizer". By heating it under pressure, at about 150 °C., Baekeland was able to suppress the foaming that would otherwise occur. The resulting substance was extremely hard and both infusable and insoluble. SIZE: see attached ruler photo. Photos are part of the description representing the condition report and can be used for authentication prior to the sale date. Pangaea Auctions urges Bidder's to view all attached photos in detail. #(American, 19th-20th Century, Jewelry, Bangle, Bakelite, Bracelet, Antique, Vintage, ).