Trichloroisocyanuric acid

Caution A free stream of chlorine gas is employed in this reaction, which should therefore be conducted in an efficient hood. 

A 500-ml three-necked flask is fitted with a mechanical stirrer, a thermometer, a gas outlet, and a gas inlet tube dipping into the solution. The flask is charged with a solution of cyanuric acid (15 g, 0.116 mole) dissolved in 300 ml of 5% aqueous potassium hydroxide solution. The flask is cooled in an ice-salt bath with stirring to 0° and irradiated with a mercury lamp. A rapid stream of chlorine is passed into the flask (approx. 5 ml/sec), whereupon a heavy white precipitate forms. The addition of gas is continued until the solid material no longer forms (approx. 2 hours). The flask is briefly flushed with air, the product is collected by suction filtration in an ice-cooled funnel, and the residue washed with several small portions of cold water. Since it undergoes slow hydrolysis, the product should be dried in a vacuum oven. The crude product has a variable melting point (195-225°) the yield is about 20 g (approx. 75%). 

The crude product (or the commercially available material) may be recrystallized from ethylene chloride giving colorless needles, mp 246-247° (dec) (//). 

Yuki Gosei Kagaku Kyokai Shi IS, 241 (1957) Chem. Abstr. 51 12107/1 (1957). 

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ChlorinatedIsocya.nura.tes. The cyanuric acid-based sanitizers, introduced for pool use in 1958, are stable crystalline compounds with moderate-to-high available CI2. Sodium dichloroisocyanurate (Dichlor), sold in granular form, dissolves rapidly, whereas trichloroisocyanuric acid (Trichlor) dissolves very slowly and is widely used in the form of tablets or sticks in feeders, floating devices, or in the pool skimmer. 

Sodium bicarbonate is generally added to increase alkalinity and muriatic acid (HCl) or sodium bisulfate (NaHSO ) to reduce it. In general, with acidic sanitizers such as chlorine gas or trichloroisocyanuric acid, ideal total alkalinity should be in the 100—120 ppm range, whereas, with alkaline products such as calcium, lithium, or sodium hypochlorite, a lower ideal total alkalinity of 80—100 ppm is recommended (14). Alkalinity is deterrnined by titration with standard sulfuric acid using a mixed bromcresol green—methyl red indicator after dechlorination of the sample with thiosulfate. Dechlorination with thiosulfate causes higher readings due to formation of hydroxyl ion (32) ... 

Toxicity of Chlorine Sanitizers. Chlorine-based swimming-pool and spa and hot-tub sanitizers irritate eyes, skin, and mucous membranes and must be handled with extreme care. The toxicities are as follows for chlorine gas, TLV = 1 ppm acute inhalation LC q = 137 ppm for 1 h (mouse) (75). The acute oral LD q (rats) for the Hquid and soHd chlorine sanitizers are NaOCl (100% basis) 8.9 g/kg (76), 65% Ca(OCl)2 850 mg/kg, sodium dichloroisocyanurate dihydrate 735 mg/kg, and trichloroisocyanuric acid 490 mg/kg. Cyanuric acid is essentially nontoxic based on an oral LD q > 20 g/kg in rabbits. Although, it is mildly irritating to the eye, it is not a skin irritant. A review of the toxicological studies on cyanuric acid and its chlorinated derivatives is given in ref. 77. 

Dichlorine monoxide, generated in situ in the presence of CCl by reaction of CO2 and NaOCl, has been used in preparation of substituted hydra2ines (48). Dichlorine monoxide reacts with finely divided cyanuric acid in a fluidized bed forming dichloro- and trichloroisocyanuric acids (49) and with sodium cyanurate monohydrate yielding sodium dichloroisocyanurate monohydrate (50) (see Cyanuric and isocyanuric acids). 

The kinetics of /V-ch1orination of CA iu basic media have been studied by stopdow spectrophotometry (21). The A/-chloro derivatives are the most important commercial products derived from CA. Their av CI2 and other values appear iu Table 2. Trichloroisocyanuric acid [87-90-17, TCCA, or l,3,5-trichloro-j -tria2iQe-2,4,6(lJT,3JT,5J-i)-trione, is obtained iu - 90% yield by cblorination of aqueous trisodium cyanurate, prepared from CA and NaOH iu a 1 3 molar ratio (22). 

Chemical Designations - Synonyms Trichloroiminoisocyanuris acid Trichloroisocyanuric acid Trichloro-s-Triazine-2,4,6-(lH,3H,5H)-trion Trichlorotriazinetrion 1,3,5- Trichloro- 2,4,6-trioxo-1,3,5-triazine Chemical Formula Cl3(NCO)3. 

Tricliloroethane, 131 Trichloroethylene, 131 Trichloroethylsilane, 131 Trichlorofluromethane, 132 Trichloroisocyanuric acid, 131 Trichloronate, 131 Trichlorophenols, 132 Trichlorophenylsilane, 132... 

B. n-BuTYL Butyrate from Di- -butyl Ether by Trichloroisocyanuric Acid (17)... 

In a 200-ml round-bottom flask equipped with a magnetic stirrer and a thermometer is placed a mixture of 50 ml of di- -butyl ether and 25 ml of water. The flask is immersed in an ice bath and the mixture is cooled to 5°. In one portion is added 23.2 g (0.1 moles) of trichloroisocyanuric acid (Chapter 17, Section IV), and stirring in the ice bath is continued for 12 hours. The ice bath is removed and the mixture is stirred at room temperature for an additional 8 hours. The reaction mixture is then filtered to remove solids. The water is separated from the organic layer, which is then washed with two additional portions of water, dried with anhydrous sodium sulfate, filtered, and fractionated as above. 

Trichloroisocyanuric acid (Chapter 17, Section IV) Chemicals Procurement Laboratories, College Point, N.Y. 

The application of surface treatments to mbbers should produce improved wettability, creation of polar moieties able to react with the adhesive, cracks and heterogeneities should be formed to facilitate the mechanical interlocking with the adhesive, and an efficient removal of antiadherend moieties (zinc stearate, paraffin wax, and processing oils) have to be reached. Several types of surface preparation involving solvent wiping, mechanical and chemical treatments, and primers have been proposed to improve the adhesion of vulcanized SBR soles. However, chlorination with solutions of trichloroisocyanuric acid (TCI) in different solvents is by far the most common surface preparation for mbbers. 

Halogenation with Organic Solvent Solutions of Trichloroisocyanuric Acid... 

FIGURE 27.4 ATR-IR spectra of 2 wt% trichloroisocyanuric acid (TCI) solution in MEK-treated styrene-butadiene rubber (SBR). Application of the chlorinating agent by immersion or by brush. (From Romero-Sanchez, M.D., Pastor-Bias, M.M., and Martfn-Martfnez, J.M., J. Adhes. Sci. TechnoL, 15, 1601, 2001.)... 

Bemabeu-Gonzalvez A., Pastor-Bias M.M., and Martm-Martmez J.M., 1998, Modified adhesion of rubber materials by surface migration of wax and zinc stearate, in Proceedings of the World Polymer Congress, 37th International Symposium on Macromolecules MACRO 98, Gold Coast, Australia, 705. Romero-Sanchez M.D., Pastor-Bias M.M., and Martm-Martmez J.M., 2001, Adhesion improvement of SBR rubber by treatment with trichloroisocyanuric acid solutions in different esters, Int. J. Adhes. Adhes., 21, 325-337. 

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