Rubber sponge

Dielectric dryers have not as yet found a wide field of application. Their fundamental characteristic of generating heat within the solid indicates potentialities for diying massive geometrical objects such as wood, sponge-rubber shapes, and ceramics. Power costs may range to 10 times the fuel costs of conventional methods. 

A non-pneumatic tyre which has an internal cavity which may be filled with sponge rubber or may be pressurised by inflation with an air needle. 

Chicago, II., 13th-16th April 1999, Paper 69, pp.36 OPTIMIZATION OF THE PRODUCTION OF EPDM SPONGE RUBBER SEALS FOR THE AUTOMOTIVE INDUSTRY... 

The manufacture of sponge rubber products such as gaskets for heat exchangers is based on the inclusion in the compound of chemicals which cause gas formation during vulcanization and thereby produce the desired porosity. Sodium bicarbonate and ammonium bicarbonate are examples of popular blowing agents. 

NaN, is used as an initiator for emulsion polymerization (Ref 137), as a cellulating agent (Ref 134) and as a retarder (Ref 185) in the manuf of sponge rubber. The addn of NaN, an alkali bicarbonate and an alkali to form a compn of pH 9-12 prevents or reduces plating out or coagulation of styrene and butadiene latexes stored in contact with metals (Ref 162). NaN, is used also to decomp nitrites in the presence of nitrates (Ref 172). The rate of nitrite decompn is increased with an increase in azide concn. Acosta (Ref 172) detd the optimum ratio to be CNaN,/CNaNO, 3-9- Compds of the structure R,R (- 0) (- NH) have been prepd from the corresponding sulfoxide and NaN, + H,S04 in chlf soln (Ref 171) ... 

Ultrasonic detection has proved to be an excellent tool for characterizing blowing processes, as shown by monitoring blowing in sponge rubber via measurements... 

In the case of cellular rubber, the ASTM uses several classifications based on the method of manufacture [11,12]. Cellular rubber is a general term covering all cellular materials that have an elastomer as the polymer phase. Sponge rubber and expanded rubber are cellular rubbers produced by expanding bulk rubber stocks, and are open-cell and closed- cell, respectively. Latex foam rubber, which is also a cellular rubber, is produced by frothing a rubber latex or liquid rubber, gelling the frothed latex, and then vulcanizing it in the expanded state. 

NIOSH REL (Nitriles) CL 6 mg/mVl5M SAFETY PROFILE Poison by ingestion, intraperitoneal, and intravenous routes. An experimental teratogen. A human skin irritant and allergen. In the preparation of sponge rubber, an azo compound is used that decomposes to form tetramethylsuccinonitrile or TMSN. Rats exposed to a concentration of 90 ppm exhibit their first convulsion after 1.5-2 hours or less. Rats exposed to concentration of 5.5 ppm exhibited their first convulsions in 27-31 hours and were dead in 31-46 hours. Absorbed by skin. The fatal dose in humans is thought to be about 25 mg/kg of body weight. TSN is slowly detoxified by the body. This nitrile is different from other nitriles in that thiosulfate is a poor antidote for intoxication. When heated to decomposition it emits toxic fumes of CN and NOx. See also NITRILES and CYANIDE. 

CafNjJj, as well as Ba(N,), or NaN, has been recommended as a cellulatlng agent in the prepn of sponge rubber (Ref 17)... 

There are a wide variety of insulation materials available in the market, but most are primarily made of fiberglass, mineral wool, polyethylene, foam, or calcium silicate. They come in various trade names such as granulated bulk mineral wool insulation, cork insulation sheets, foil-faced fiberglass insulation, blended sponge rubber sheeting, and numerous others. 

Zimmerman, R.L. and BaUey, H.R., Chapter 4, "Sponge Rubber and Latex Foam," in Plastic Foams, Part 1, eds. Frisch, K.C. and Saunders, J.H., Marcel Dekker, New York (1972). 

Covers two vocedures for determining the compression-de-flection characteristics of rubber compounds other than those usually classified as hard rubber or sponge rubber. 

Notice 1 states that the specification is currently valid for use in acquisition. The original date of the base specification was 25 June 1982. The cushions are intended for use in assembly of rocket motors for M753, 8-inch projectiles. Type I covers soft-grade silicone sponge rubber and Type II medium-grade silicone sponge rubber. 

Covers only sponge rubber items, including chemically blown or expanded-rubber items having either open or closed cells. Also includes cellular products made from chemically or mechanically foamed latices or liquid elastomers. Provides word descriptions and photographs of defects. 

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