Xylyl mercaptan

A substance added to latex in the preparation of pale crepe rubber sodium bisulphate prevents darkening of the crepe due to the presence of oxidising enzymes, xylyl mercaptan is an effective bleaching agent proper. 

Xylol (dimethylbenzene), used as a rubber solvent. Xylene exists in three isomeric forms, commercial xylol being a mixture of all three. Xylyl Mercaptan... 

Elastic-gel comp proplnt is prepd by milling oil-extended GR-S rubber (contg 100 parts rubber 30 ps oil) with 5 ps RPA No 3 (A 36.5% soln of xylyl mercaptan in a hydrocarbon solvent), 5 ps ZnO 1 part stearic acid. Then 300 ps oil is added, in small increments, followed by Captax 12, Tuads 6, diphenylguanidine 18, C black 20, sulfur 6 and finally AN (50-100 mesh) 1892 parts. The batch is mixed 60 mins, deaerated, cast and cured for 24 hrs at 220°F] DD)C.C.Rice W.B.Reynolds, USP 2993769 (1961) CA 55, 27891 (1961) [Comp proplnt prepd by mixing petroleum pitch with a polymer, a phase -stabilized Amm nitrate Amm dichromate. 

Solution-polymerized SBR is made by termination-free, anionic/live polymerization initiated by alkyl lithium compounds. Other lithium compounds are suitable (such as aryl, alkaryl, aralkyl, tolyl, xylyl lithium, and ot/p-naphtyl lithium as well as their blends), but alkyl lithium compounds are the most commonly used in industry. The absence of a spontaneous termination step enables the synthesis of polymers possessing a very narrow molecular weight distribution and less branching. Carbon dioxide, water, oxygen, ethanol, mercaptans, and primary/secondary amines interfere with the activity of alkyl lithium catalysts, so the polymerization must be carried out in clean, near-anhydrous conditions. Stirred bed or agitated stainless steel reactors are widely used commercially. 

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