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Economic diluent

Special fine-particle kaolin clays are commonly used in rubber compounding as economic diluents, mainly to reduce the cost and improve processability. Clays that are used by the rubber industry require further processing to remove larger particles and impurities, which prevents the decrease of the rubber product s cured physical properties. [Pg.33]

Raw limestone is used to produce whiting (ground limestone) as an economical diluent filler in rubber compounding. It is also used as a feedstock to manufacture precipitated calcium carbonate, which is also used as a little more costly, but better, filler for extending a rubber formulation. [Pg.36]

Kaolin clay is basically used as an economic diluent to reduce the cost of some rubber formulations. If used at all, kaolin is typically used at 20 to 150 parts per hundred rubber. Clay is not used very much in tire applications. However, it is a common raw material for many nontire applications. [Pg.219]

Calcium carbonate is another inexpensive filler used in rubber compounding as an economic diluent. [Pg.220]

Powdered taic is another economical diluent filler however, it is commonly used instead of ciay or ground iimestone because talc possesses some lubricity properties that allow it to function as a processing aid. Also, talc particles are platelets in shape, which can impart a better barrier to gas permeability than either clay or whiting. [Pg.223]

Because of talc s lubricity characteristics and the concomitant improvements in a rubber compound s flow characteristics in extrusion or injection molding, there could be problems in directly substituting it for clay or whiting. Also, talc does a better job of imparting reduced air permeability than the other economic diluents. It has been reported that ground mica and clay together can sometimes be used to substitute for ground talc. [Pg.223]

Ground coal is mainly used as a black economic diluent in rubber compounding. Most of the ground coal use in rubber occurs in the United States. [Pg.227]

Other economic diluent fillers, such as clay, whiting, and talc, are available for use in rubber. [Pg.227]

There are but a few producers of ground coal, but there is no significant history of shortages either. Other economic diluent fillers are usually readily available. [Pg.227]

The derivatives are hydroxyethyl and hydroxypropyl cellulose. AH four derivatives find numerous appHcations and there are other reactants that can be added to ceUulose, including the mixed addition of reactants lea ding to adducts of commercial significance. In the commercial production of mixed ethers there are economic factors to consider that include the efficiency of adduct additions (ca 40%), waste product disposal, and the method of product recovery and drying on a commercial scale. The products produced by equation 2 require heat and produce NaCl, a corrosive by-product, with each mole of adduct added. These products are produced by a paste process and require corrosion-resistant production units. The oxirane additions (eq. 3) are exothermic, and with the explosive nature of the oxiranes, require a dispersion diluent in their synthesis (see Cellulose ethers). [Pg.314]

The second largest use at 21% is for unsaturated polyester resins, which are the products of polycondensation reactions between molar equivalents of certain dicarboxyhc acids or thek anhydrides and glycols. One component, usually the diacid or anhydride, must be unsaturated. A vinyl monomer, usually styrene, is a diluent which later serves to fully cross-link the unsaturated portion of the polycondensate when a catalyst, usually a peroxide, is added. The diacids or anhydrides are usually phthahc anhydride, isophthahc acid, and maleic anhydride. Maleic anhydride provides the unsaturated bonds. The exact composition is adjusted to obtain the requked performance. Resins based on phthahc anhydride are used in boat hulls, tubs and spas, constmction, and synthetic marble surfaces. In most cases, the resins contain mineral or glass fibers that provide the requked stmctural strength. The market for the resins tends to be cychcal because products made from them sell far better in good economic times (see Polyesters,unsaturated). [Pg.485]

Two variables of primary importance, which are interdependent, are reaction temperature and ch1orine propy1ene ratio. Propylene is typically used ia excess to act as a diluent and heat sink, thus minimising by-products (eqs.2 and 3). Since higher temperatures favor the desired reaction, standard practice generally involves preheat of the reactor feeds to at least 200°C prior to combination. The heat of reaction is then responsible for further increases in the reaction temperature toward 510°C. The chlorine propylene ratio is adjusted so that, for given preheat temperatures, the desired ultimate reaction temperature is maintained. For example, at a chlorine propylene molar ratio of 0.315, feed temperatures of 200°C (propylene) and 50°C (chlorine) produce an ultimate reaction temperature of approximately 500°C (10). Increases in preheat temperature toward the ultimate reactor temperature, eg, in attempts to decrease yield of equation 1, must be compensated for in reduced chlorine propylene ratio, which reduces the fraction of propylene converted and, thus aHyl chloride quantity produced. A suitable economic optimum combination of preheat temperature and chlorine propylene ratio can be readily deterrnined for individual cases. [Pg.34]

Cycle Diluents. Air process technology uses nitrogen as the diluent gas. The amount of nitrogen that enters the process in the air feed caimot be economically diluted (97). [Pg.459]

Another environmental issue is the use of organic solvents. The use of chlorinated hydrocarbons, for example, has been severely curtailed. In fact, so many of the solvents favored by organic chemists are now on the black list that the whole question of solvents requires rethinking. The best solvent is no solvent, and if a solvent (diluent) is needed, then water has a lot to recommend it. This provides a golden opportunity for biocatalysis, since the replacement of classic chemical methods in organic solvents by enzymatic procedures in water at ambient temperature and pressure can provide substantial environmental and economic benefits. Similarly, there is a marked trend toward the application of organometal-lic catalysis in aqueous biphasic systems and other nonconventional media, such as fluorous biphasic, supercritical carbon dioxide and ionic liquids. ... [Pg.195]

The heart of an extraction process plant is the solvent, it is the essential element of a given extraction process. It determines the efficiency and the economics of a process. In general, the solvent is a mixture of several organic compounds, which include the diluent, the extracting agent, and the modifiers. [Pg.157]

One of the most economical routes to most commercial grades of olefin polymers is the loop slurry process with a paraffin diluent. This process was introduced by Chevron Phillips in 1960 (7). There, a mixture of catalyst particles, growing polymer particles, comonomers, and diluent is pumped in a loop. The polymer particles are harvested by guiding a side stream of the slurry to settling chambers, where the polymer particles settle toward the bottom. [Pg.78]

Further development of emulsion transport technology is dependent upon future economic factors such as increases in the price of heavy crude oil and potential shortages of diluent. Commercial operation of an emulsion transport system is required to determine the long-term technical and economic viability of this technology. [Pg.312]


See other pages where Economic diluent is mentioned: [Pg.34]    [Pg.221]    [Pg.222]    [Pg.34]    [Pg.221]    [Pg.222]    [Pg.80]    [Pg.11]    [Pg.481]    [Pg.459]    [Pg.238]    [Pg.526]    [Pg.318]    [Pg.112]    [Pg.71]    [Pg.71]    [Pg.509]    [Pg.419]    [Pg.54]    [Pg.270]    [Pg.74]    [Pg.459]    [Pg.30]    [Pg.389]    [Pg.282]    [Pg.78]    [Pg.238]    [Pg.237]    [Pg.8]    [Pg.256]    [Pg.315]    [Pg.481]    [Pg.2335]    [Pg.1791]   
See also in sourсe #XX -- [ Pg.219 , Pg.220 , Pg.227 ]




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Diluents

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