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Primary final product

The potential function of each chemical is also indicated PR = primary rawmaterial, SR = secondary raw material, I = intermediate, PF = primary final product, SF = secondary final product. [Pg.87]

The final product may, however, result from primary nitrogen attack followed by rearrangement (163. 165). [Pg.34]

Diester/Ether Diol of Tetrabromophthalic Anhydride. This material [77098-07-8] is prepared from TBPA in a two-step reaction. First TBPA reacts with diethylene glycol to produce an acid ester. The acid ester and propylene oxide then react to give a diester. The final product, a triol having two primary and one secondary hydroxyl group, is used exclusively as a flame retardant for rigid polyurethane foam (53,54). [Pg.470]

The newly formed short-chain radical A then quickly reacts with a monomer molecule to create a primary radical. If subsequent initiation is not fast, AX is considered an inhibitor. Many have studied the influence of chain-transfer reactions on emulsion polymerisation because of the interesting complexities arising from enhanced radical desorption rates from the growing polymer particles (64,65). Chain-transfer reactions are not limited to chain-transfer agents. Chain-transfer to monomer is ia many cases the main chain termination event ia emulsion polymerisation. Chain transfer to polymer leads to branching which can greatiy impact final product properties (66). [Pg.26]

Secondary Plasticizers. Also known as extenders, secondary plasticizers continue to play a significant role ia flexible PVC formulations. They do not impart flexibiHty to the PVC resia alone, but when combiaed with a primary plasticizer act ia such a way as to add flexibiHty to the final product. [Pg.123]

Uses. Principal uses of com symps are shown in Table 4. The specific type of symp employed depends on the properties desired in the final product. Symp properties are important to varying degrees in different products, and changes in formulation can affect the choice of symp required to supply the most desirable properties. In many cases, com symps are used as supplementary sweeteners when sucrose is the primary one. [Pg.295]

Secondary Timber Products. Secondary timber products are products manufactured from primary timber products. Secondary products can be sold directly to the final consumer or can requite additional processing before reaching the final consumer. The wide diversity of products manufactured from primary timber products makes it difficult to precisely define secondary products. Lumber, for example, is clearly a secondary product because it is manufactured from roundwood and typically requites further processing before reaching its final use. Wooden furniture is considered a final product, not a secondary product because it is made from lumber or other secondary timber products. In general, products made from secondary timber products were not included in this analysis. [Pg.333]

In many instances the primary reaction product is a dihydropyrazine and aromatization may be required as a final step. In addition, many pyrazines are prepared by the structural modification of a preformed pyrazine ring and hence would be classified as a reaction of the ring rather than a ring synthesis such processes are discussed more fully in Section 2.14.2. [Pg.179]

Aromatic ethers and furans undergo alkoxylation by addition upon electrolysis in an alcohol containing a suitable electrolyte.Other compounds such as aromatic hydrocarbons, alkenes, A -alkyl amides, and ethers lead to alkoxylated products by substitution. Two mechanisms for these electrochemical alkoxylations are currently discussed. The first one consists of direct oxidation of the substrate to give the radical cation which reacts with the alcohol, followed by reoxidation of the intermediate radical and either alcoholysis or elimination of a proton to the final product. In the second mechanism the primary step is the oxidation of the alcoholate to give an alkoxyl radical which then reacts with the substrate, the consequent steps then being the same as above. The formation of quinone acetals in particular seems to proceed via the second mechanism. ... [Pg.94]

The first step is to identify the substances present at the workplace. As a starting point, knowledge of the process is needed in order to formulate a list of all chemical agents used in the establishment. The list should include not only primary products but also intermediate and final products, as well as reaction products and by-products. For the chemical agents in the list, it is necessary to know their chemical properties, especially hazardous ones their OEL values, including biological limit values and, where these are not available, other technical criteria that can be used to evaluate the risk. It is also helpful to include any information on the safety and health risks of those substances provided by the supplier or other readily available sources. This information on dangerous substances and preparations, in the form of safety data sheets, is intended primarily for industrial users, to enable them to take the measures necessary to ensure the safety and health of workers. [Pg.369]

Dinitro ketone 49 with potassium cyanide provided 5,6-dihydrooxazolo [3,2-/7][l,2,4]triazole 51. Its formation is due to the fact that primary attack by the cyanide anion is not directed at the ring C5 atom but rather at the carbonyl group to give the corresponding cyanohydrin 50 and the subsequent intramolecular displacement of the nitro group gives the final product (Scheme 8) (81 KGS 1403). [Pg.195]

Some typical dispersion polymerization recipes and the electron micrograph of the uniform polymeric particles with Recipe I are given in Table 5 and Fig. 10, respectively. As seen in Table 5, the alcohols or alcohol-water mixtures are usually utilized as the dispersion media for the dispersion polymerization of apolar monomers. In order to achieve the monodispersity in the final product, a costabilizer can be used together with a primary steric stabilizer, which is usually in the polymeric form as in... [Pg.202]

The method based on the precipitation of peroxometalate precursors enables to achieve additional purification during the process. Thus, the addition of complexonates, such as OEDP or EDTA, which form stable complexes with some polyvalent metals, prevents co-precipitation of the main impurities such as Fe, Co, Ni, Mn, Mg, etc., which in turn significantly increases the purity of the final product. Enhanced purification can also be achieved by recrystallization of the precursor. Particularly, the precipitation of ammonium peroxofluorometalates, such as ammonium peroxofluoroniobate ((NH4)3Nb04F4), as a primary precursor, leads to significant reduction of the titanium contamination. Ammonium peroxofluoroniobate, (NH4)3Nb04F4, is... [Pg.307]

As seen from (Scheme 12-73) the primary product of arylazo substitution is the anion Ar - N2 - R . It is protonated in a subsequent step either at a basic center of the residue R (preferentially at an oxygen atom, for example, in coupling with phenol), or at the azo nitrogen next to the group Ar forming a hydrazone. The problem as to whether the final product is a hydroxyazo- or a quinonehydrazone-type... [Pg.363]

Rocky Flats is a Government-owned and contractor-operated facility which originated in 1952. The plant s primary missions are metal fabrication, assembly, and chemical processing—with emphasis on production-related research and development. Chemical processing activities involve the recovery of plutonium from Rocky Flats Plant scrap, waste materials and residues, and effluent streams. The final product of this recovery and purification effort is high-purity plutonium metal for use in foundry operations. [Pg.365]

The addition, therefore, follows Markovnikov s rule. Primary alcohols give better results than secondary, and tertiary alcohols are very inactive. This is a convenient method for the preparation of tertiary ethers by the use of a suitable alkene such as Me2C=CH2. Alcohols add intramolecularly to alkenes to generate cyclic ethers, often bearing a hydroxyl unit as well. This addition can be promoted by a palladium catalyst, with migration of the double bond in the final product. Rhenium compounds also facilitate this cyclization reaction to form functionalized tetrahydrofurans. [Pg.996]

UV photolysis (Chapman et al., 1976 Chedekel et al., 1976) and vacuum pyrolysis (Mal tsev et al., 1980) of trimethylsilyldiazomethane [122]. The silene formation occurred as a result of fast isomerization of the primary reaction product, excited singlet trimethylsilylcarbene [123] (the ground state of this carbene is triplet). When the gas-phase reaction mixture was diluted with inert gas (helium) singlet-triplet conversion took place due to intermolecular collisions and loss of excitation. As a result the final products [124] of formal dimerization of the triplet carbene [123] were obtained. [Pg.47]

If we wish to characterize a solid state reaction, from initial compound(s) to final product(s), there are only a few methods we can use. Of primary importance is x-ray identification since we must know what we started with, and what we end up with. We have already discussed the x-ray method in some detedl in the second chapter and how one goes about using that method. [Pg.357]

Degradation of the insecticide chlorpyrifos has been examined in solutions of aqueous chlorine in which the primary oxidant is hypochlorous acid/hypochlorite. The final product was 2,3,5-trichloropyrid-2-one produced either directly, or via initial oxidative conversion of the thioate ester by replacement of the sulfur with oxygen (Duirk and Collette 2006). An analogous oxidation was found with diazinon (Zhang and Pehkonen 1999). [Pg.33]

The chlorination of the antibacterial sulfonamide sulfamethoxazole was initiated by N-chlorination of the primary amine. Further reaction of the A,A-dichlorinated compound resulted in the final production of 3-amino-5-methyloxazole and 1,4-benzoquinone-imine (Dodd and Huang 2004). [Pg.33]


See other pages where Primary final product is mentioned: [Pg.168]    [Pg.84]    [Pg.213]    [Pg.84]    [Pg.626]    [Pg.168]    [Pg.84]    [Pg.213]    [Pg.84]    [Pg.626]    [Pg.417]    [Pg.402]    [Pg.445]    [Pg.105]    [Pg.249]    [Pg.554]    [Pg.477]    [Pg.455]    [Pg.499]    [Pg.513]    [Pg.520]    [Pg.226]    [Pg.186]    [Pg.97]    [Pg.207]    [Pg.710]    [Pg.290]    [Pg.11]    [Pg.223]    [Pg.557]    [Pg.12]    [Pg.30]    [Pg.274]   
See also in sourсe #XX -- [ Pg.84 ]

See also in sourсe #XX -- [ Pg.84 ]




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Final product

Final product production

Final product, primary/secondary

Primary productivity

Primary products

Production primary

Production/productivity primary

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