Vulcanite

VSEPR theory See valency, theory of. vulcanite See ebonite. 

In extensions of this work on vulcanisation, which normally involved only a few per cent of sulphur, both Goodyear and Hancock found that if rubber was heated with larger quantities of sulphur (about 50 parts per 100 parts of rubber) a hard product was obtained. This subsequently became known variously as ebonite, vulcanite and hard rubber. A patent for producing hard rubber was taken out by Nelson Goodyear in 1851. 

Also known as vulcanite and (mainly in the USA) hard rubber . The hard, horn-like product obtained when natural rubber and some synthetic rubbers such as nitrile (NBR) are vulcanised with a high proportion of sulphur or organic nonsulphur vulcanising agent. Butyl rubber and polysulphide rubber do not form ebonites. Ebullioscopy... 

Technical Importance of the Aldehydes.—Formalin solution is used as a disinfectant and as a preservative. Caseinogen hardened with formaldehyde is a widely used substitute for vulcanite, as is also the synthetic resin bakelite, which is produced by the condensation of formaldehyde with phenol (p. 243). 

Irrigators are medicated solution used to treat urinary bladder, vagina and less often the nose infections. They are administered with a help of catheter (in bladder), vulcanite (for vagina) which are made up of thin, soft rubber or plastic tube. The nose irrigator is made up of glass. 

Vulcanite PR. A mining expl suitable for tunnel work thru hard rock. It is based on inorg nitrates nitroaromatic compds. Its Trauzl value is 510cc, Deton Vel 560Qm/sec at d 1.15 Impact 70cm [Catalog of Vulcania SPA,... 

VE4, Vulcania D.B., Vulcania D.B.S., Vulcanite P, Vulcanite PR and Sismite A. Compns are given without numerical values... 

Classe dei Super Pulverulenti", which contains some NG about 70% of nitrates (mostly of Amm), tritolo (TNT), or pantrite (PETN) or T4 (Cyclonite). To this class belong Ital expls Superdinamon, Super BM galleria, Titan C and Vulcanite... 

Vulcanite. A mining expl patented near the end of the last century by Moritz and Koppel of Austria. Two variations are given ... 

See also as Vulcanite P and Vulcanite PR under Italian Explosives and Related Items in Vol 7,1182-L... 

Vulcanite P (inorg nitrates, aromatic nitrocompds org nitrates) for tunneling in hard rock... 

Vulcanite PR (inorg nitrates, arom nitrocompds. other ingredients) for tunneling in hard rode In addn to the above listed Italian nonper-missible expls, the following may be included Albita italiana AN 58, NGu 19 8t GuN 23%... 

Figure 27 Synthetic plastics imitated successfully exclusive natural materials a Bakelite ash tray with built-in match holder and striker in marble Roanoid, with marbleized, brass-tipped cigarette holder, 1930s. Carvacraft desk set in amber cast phenolic, 1948-51 double inkwell, notepad holder, blotter and paper knife with clear acrylic blade. Smiths Sectric alarm clock with marbleized urea-formaldehyde case, 1932. Ardath Tobacco cigarette box in ivory and black urea-formaldehyde with lid moulded to simulate a classical relief, 1935. Propelling pencil with black and orange mottle typical of vulcanite, 1930s (Photo Stephen Brayne, Collection Sylvia Katz)...

Hard rubber has a variety of names, some of which may denote differences in composition or plants of origin. These include ebonite, bone rubber, gutta-percha, and vulcanite. Gutta-percha is technically a product of Asia, from different plants than those that produce rubber, but these terms are often used interchangeably for any rigid rubber material. 

Vulcanized rubber can be carved, or, more importantly, molded into almost any shape. The uses for this versatile, water-proof, flexible material increased with time. These included household and decorative objects, apparel, personal items, insulation, and equipment and materials for use in medicine, the military, and industry. Vulcanized rubber also goes under the commercial names vulcanite and ebonite. 

Gutta peavha in its pure fium is white, and in crude form can be brown or black. It has the same chemical formula as rubber but a di rent physical state. It was not vulcanised as it was for too valuable a material and was prized for its elasticity and plasticity, and would have been ruined by vulcanisation. It was very easy to mould and could take intricate patterns, but to be made into jewellery, it would have needed to be hardened in some way. Gutta percha was less durable than vulcanite, and cracked and deteriorated when closed to air over a lot period of time. Instead it kept... 

Figure 2.9 VulcanitE c hain link which has not been cut tfarou. ...

A material that is losing its colour cannot be jet or coal, and is likely to be vulcanite, which turns from greenish-brown to khaki with age (Fig. 2.3). 

Under magnification vulcanite will not show complete eveimess of colour and may display tiny spots. The slightly dimpled surface will also be visible (Fig. 2.6). 

It is unlikely that vulcanite will show firactures, but it may display worn edges. 

An object with clasps or pins screwed into place indicates vulcanite (F, 2.11),... 

Chain links with only one cut in them cannot be jet as they would have to be sl tly flexible to be opened and linked together. Jet is rigid, so flexible links indicate vulcanite or horn (Figs 2.7 and 2.9). 

Broodi fittings lefi, vulcanite with metal pins right, jet with... 

Jetj coal, and vulcanite are opaque. An item that shows transparency in thin areas by transmitted light indicates glass or horn, or possibly celluloid or Bakelite. 

Burning. If there is still doubt about an item, it may be possible to take a very tiny scraping firom an inconspicuous part and bum it. Jet and other coals will bum with a coal-like smell. Vulcanite will... 

A further test is possible to determine if an object is made from vulcanite ... 

Placed on a piece of silver for a day or two, the sulphur content of vulcanite should leave a mark on the silver. The silver must be abraded dean as in a dishwasher, and not polished dean with a deaner that leaves a protective film. Only vulcanised jet simulants will do this. 

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