Rubber poison content

Rtihl [141] has reported on very large scale SS-GFAAS and XRF analysis of Cd in polymers for product control purposes in the automobile industry (approximately 20 000 parts per year) as a reaction on a Swedish law for environmental protection (upper limit of 75ppm). Another sample of direct SS-GFAAS in industry is the control of all raw materials, processing steps, and products for adhesive tapes for the content of Cu, Mn, Fe, Cd and Pb, which act as a rubber poison by catalytic effects [144]. 

Problems may arise if P.B.15 1 is to be used in natural rubber, because the presence of free copper affects not only the vulcanization process, but also considerably affects the fastness of the product to aging. P.B.15 1 is thus considered a rubber poison. The free copper content in a pigment should therefore never exceed 0.015%. Commercial types are available which have been tested accordingly. 

The CPA or "Snake Pen" consists of a pen body containing a porous wick, such as that used in felt pens, and a solution ofDMSO and any number of toxins. When the wick is touched to the victim s skin he receives a fatal dose of poison. The CPA is built from a correction fluid pen, available at any office supply store. These pens have a soft, flexible body and are easy to modify. Unscrew the top from the son pen body, squeeze out the correction fluid and flush the interior with solvent to remove all traces of its original contents. Note that most of these pens have a left-hand thread on the body. The tip of the pen is sawed off and the valve stem carefully removed. Ream out the pen tip to fit the wick. A felt tip marker pen works well as a wick, after being soaked and rinsed in sol vent to remove traces of ink. It may be necessary to trim the wick to fit. Press the wick into the pen tip until about 3/8 " protrudes and seal around it with silicone sealer. When the sealant is dry, put on rubber gloves and, using a hypodermic syringes, inject the DMSO solution into the pen barrel until it is about 3/ 4 full. Be sure not to squeeze the pen while accomplishing this. Coat the barrel threads with a little silicone sealer, screw on the cap and allow the pen to dry in a vertical position. Line the inside of the cap... 

The solution containing the arsenic compound is then added in small amounts at a time to the contents of the flask. If much arsenic is present, there will be an almost immediate blackening of the silver nitrate solution. Disconnect the rubber tube at C. Heat the tube at A to just below the softening point a mirror of arsenic is deposited in the cooler, less constricted portion of the tube. A second flame may be applied at B to ensure complete decomposition (arsine is extremely poisonous). When a satisfactory mirror has been obtained, remove the flames at A and B and apply a light at C. Hold a cold porcelain dish in the flame, and test the solubility of the black or brownish deposit in sodium hypochlorite solution. 

Benzene is a colorless, poisonous liquid with a specific odor. It dissolves in organic solvents such as ether, alcohol, acetone and acetic acid. Benzene is also a good solvent for non-polar substances, it is used to dissolve fats, resins, rubber, iodine and sulfur. Its carbon content is high, therefore, when burned, it gives a sooty flame. 

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