Hoechst applications

The application of metallocene catalysis to the preparation of polypropylenes reached a commercial stage with the production by Exxon of their Achieve range in 1996 and in 1997 by Targor, the BASF-Hoechst joint venture with the introduction of Metocene. Such metallocene polypropylenes are, however, only a small proportion of the total polypropylene market, predicted at only about 3% of the total in 2005. 

Spills are covered by a variety of federal, state, and local reporting requirements and substantial penalties can result to a company and its employees for failing to report certain spills. Initial release notification is usually required immediately or within 24 hours of the release and, in some cases, written follow-up reports are required. Some of the applicable legislation is listed below and Table 64.1 lists some of the major reporting requirements for chemical spills that are specified by these Acts. However, refer to Hoechst Celanese s procedures for plant-specific requirements. 

However, daily application of up to 48 mg/kg/day (females) or 192 mg/kg/day (males) to the skin of rats for 30 days (5 days/week, 6 hours/day) caused no apparent skin irritation (Hoechst 1985c, 1985d). 

Dermal application of 587 mg/kg/day of endosulfan 3 days/week, 6 hours/day for 3 weeks caused no erythema or edema in guinea pigs (Hoechst 1983b). 

Three animal studies were located regarding distribution of endosulfan in animals following dermal exposure (Dikshith et al. 1988 Hoechst 1986 Nicholson and Cooper 1977). Endosulfan was detected in the brain (0.73 ppm), liver (3.78 ppm), and rumen contents (0.10 ppm) of calves that died after dermal exposure to a dust formulation of endosulfan (Nicholson and Cooper 1977). Following a single dermal application of aqueous suspensions of 0.1, 0.83, and 10.13 mg/kg C-endosulfan to male Sprague-Dawley rats, low concentrations of endosulfan (ng/g levels) appeared in the blood and tissues (other than skin at and around the application site) after 1 hour (Hoechst 1986). The concentrations of endosulfan in the blood and tissues increased with the time of exposure and were proportional to the dose applied. The liver and kidney appeared to sequester radiolabel relative to the concentrations of radiolabel in the blood or fat. Endosulfan levels were approximately 10 times higher in the liver and kidney than in the fat, blood, and brain throughout the study (Hoechst 1986). 

Hoechst. 1985c. Endosulfan - active ingredient technical (code HOE 02671 OIZD97 0003) Testing for subchronic dermal toxicity - 21 applications over 30 days - in Wistar rats. Hoechst Aktiengesellschaft, Frankfurt, Germany. Report no. 84.0223. [unpublished study]... 

Proposal to Withdraw Approval of Two New Drug Applications and One Abbreviated New Drug Application Terfenadine, Hoechst Marion Rousssel, Inc and Baker Norton Pharmaceuticals, Fed Regist., Docket No. 96N-0512, 1997, 1998. Part 216 Pharmacy Compounding, Drug Products Withdrawn or Removed From the Market for Reasons of Safety or Effectiveness, Cite 216.24. 

A final example of MDFI exploiting polarization resolution is given in Fig. 4.12. This shows the application of optically sectioned TR-FAIM to image ligand binding in a microfluidic reactor [67], Solutions of a small dye molecule (Hoechst 33258) and a (nonfluorescing) 5.8 kbp DNA plasmid were mixed in a 50-/mi wide... 

These products, which have been copied by other manufacturers under various tradenames, are designed specifically for printing applications. Azoic dyeing applications were catered for in 1967 when Hoechst introduced the Azanil salts, a limited range of mixtures of substantive triazenes and Naphtols that can be absorbed onto the fabric and the colour developed by acidification of the dyebath. 

Research and development work on membrane technology was begun jointly with Hoechst AG, Bayer AG and Uhde GmbH in 1973 when the first commercial membranes became available. Until now, Krupp Uhde s know-how has been based on the combined efforts of these three companies in the research and development of this technology. One result is the Single Element patented in Europe in 1980 by Hoechst AG [2] followed by patent applications all over the world [3]. 

Reduction of polymer flammability is of broad interest for applications ranging from plastics to textiles. For polyesters, given their inherent instability towards water at elevated temperatures, and the high temperatures of manufacture, many classes of flame-retardant (FR) agents, including most halogen-containing materials, are impractical. Phosphate esters, capable of incorporation into the polymer backbone, were pioneered by Hoechst AG, and continue to be the materials of choice [84, 85],... 

In many applications acetic acid is used as the anhydride and the synthesis of the latter is therefore equally important. In the 1970 s Halcon (now Eastman) and Hoechst (now Celanese) developed a process for the conversion of methyl acetate and carbon monoxide to acetic anhydride. The process has been on stream since 1983 and with an annual production of several 100,000 tons, together with some 10-20% acetic acid. The reaction is carried out under similar conditions as the Monsanto process, and also uses methyl iodide as the "activator" for the methyl group. 

There are other fluorochromes that can be used for DNA analysis. The following three are the most straightforward and reproducible with regard to application mithramycin, 4, 6-diamidino-2-phenylindole hydrochloride (DAPI), and Hoechst 33258. Concentrations must be determined empirically (see Chapter 30). 

Two-Stage Pleaching with V-BRTIE Bleach, and T -BRITE Bleaching Compounds, Product Application bulletins 10172 and 10174, Hoechst Celanese Corp., Charlotte, N.C., 1992. 

A further development of this successful technology was achieved to take advantage of the available feedstock base of butene isomers (raffinate II) for the preparation of n-C5 products (n-valeraldehyde, n-isoamyl alcohol, and n-valeric acid). In December 1995 production of n-valeraldehyde was started up in a new plant at Hoechst/Ruhrchemie (138). Generally, there are strong restrictions in the application of the two-phase catalytic processes to higher alkenes (Section IV.B.l), but the adaptation to butenes was possible with little modification of the process developed for propene. 

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