Dioctyl concentration

Pollutants. The problems posed by ak pollutants are very serious. Within a museum, measures can be taken to remove harmful substances as efficiently as possible by means of the installation of appropriate filter systems in the ventilation equipment. Proposed specification values for museum climate-control systems requke filtering systems having an efficiency for particulate removal in the dioctyl phthalate test of 60—80%. Systems must be able to limit both sulfur dioxide and nitrogen dioxide concentrations <10 /ig/m, and ozone to <2 /ig/m. ... 

Stannous Oxalate. Stannous oxalate, Sn(C20 (mol wt 206.71, dec 280°C, sp gr 3.56 at 18°C), is a white crystalline powder, is soluble in hot concentrated hydrochloric acid and mixtures of oxaHc acid and ammonium oxalate, and is insoluble in water, toluene, ethyl acetate, dioctyl phthalate, THF, isomeric heptanes, and acetone (171). It is prepared by precipitation from a solution of stannous chloride and oxaHc acid and is stable indefinitely. 

Vehicles are selected by two methods. In one a concentrate is designed directiy for a resin system, the resin itself, or a compatible resin. Thus when the concentrate is made there is a minimal effect on the properties of the final color. In PVC, often a plasticizer such as dioctyl phthalate (DOP) is used. In the other method, concentrates are made with a commercial universal concentrate vehicle. Concentrate manufacturers and some resin manufacturers have developed vehicles that can incorporate many types of colorants and can be used across many classes of polymers without adversely affecting final product performance. 

In many cases pigment-plasticizer pastes are also used for coloring PVC. Because of the mixing or embrittlement gap in the PVC-plasticizer system, which ranges from 5 to 18% for dioctyl phthalate for example, such pastes have little or no suitability for unplasticized PVC compounds. In this concentration range, which is specific for each plasticizer, no plasticizing effect is achieved, on the contrary the additive causes embrittlement of the PVC. 

At a concentration of 5 to 25 wt %, increased the effective kill-life of the lindane spray up to 10 times. May have been used in chlordane and BHC insecticide formulations. In polyurethane resin adhesive adhesive containing 16 wt % PCB-1254. Also in formulations plasticized with 3 parts dioctyl phthalate and 1 part PCB-1254 to increase chemical resistance of various polyvinyl chloride (Monsanto, 1960.)... 

Satake et al. reported the use of a coated wire electrode sensitive to procaine and other local anesthetic cations, and their application to potentiometric determination [73]. Electrodes were constructed from a copper wire (0.8 mm diameter), coated with a PVC membrane comprising a mixture of the drug-tetraphenylborate ion-pair, dioctyl phthalate, polyvinyl chloride, and tetrahydrofuran. Potential measurement was made with respect to a Ag-AgCl reference electrode. The electrodes showed linear responses with a Nemstian slope for procaine over the concentration range investigated. The method was used for analyses of the drug in pharmaceutical preparations. 

The improved thermal stability of the chlorinated paraffins also reflects the purity of the n-alkanes. The heat stability of PVC plasticized with chlorinated n-paraffin at 177°C. is better than that of similar compounds using commercial chlorinated wax. This is shown in Table I by the color that developed during thermal treatment for samples in which 40% of the dioctyl phthalate was replaced by chlorinated paraffins. (In this example and those that follow, the total plasticizer concentration is constant at 33 / %.) The color development in this test is significant as a measure of the comparative processing conditions that can be employed. 

A systematic study of the domain spacing scaling in two nearly symmetric PS-PI diblocks in neutral solvents was also undertaken by Hashimoto et al. (1983b). Results of S AXS experiments on these polymers dissolved in toluene and dioctyl phthalate (DOP) were summarized in a scaling relationship for the domain spacing in the ordered phase in the semidilute and concentrated regimes (0.15 < 4> < 0.6)... 

Fig. 4.35 Phase angle as a function of reduced frequency, determined from parallel plate rheology experiments, for a PS-PI diblock (Mv = 130kgmol, 50wt% PS) in dioctyl phthalale at a concentration 24.7 wt% polymer (Jin and Lodge 1997).

The sample was a solution of polystyrene (PS) dissolved in dioctyl phthalate (DOP). This system has a theta temperature of approximately 22°C [183] and has been the subject of most of the studies investigating flow-induced phase transitions in polymer solutions. The particular sample used here had a molecular weight for PS of 2 million, a poly-dispersity of MW/MN = 1.06, and a concentration of 6%. This results in a semidilute... 

Limited information was located regarding possible interactions of DEHP with other chemicals in humans. Urinary measurements of the monoester metabolites of seven common phthalates in 289 adults from the U.S. population, determined using the selective and sensitive analytical approach discussed in Section 3.8.1 (Biomarkers Used to Identify or Quantify Exposure to DEHP), showed detectable levels of monoethyl phthalate (95th percentile concentration, 3,750 ppb), monobutyl phthalate (294 ppb), monobenzyl phthalate (137 ppb), 2-ethylhexyl phthalate (21.5 ppb), cyclohexyl phthalate (8.6 ppb), isononyl phthalate (7.3 ppb), and octyl phthalate (2.3 ppb), reflecting exposure to DEHP, dibutyl phthalate, benzyl butyl phthalate, di-(2-ethylhexyl) phthalate, dicyclohexyl phthalate, di-isononyl phthalate, and dioctyl phthalate, respectively (Blount et al. 2000a). Considering evidence such as this which indicates that co-exposure to multiple phthalates can occur, as well as the likelihood that many of these compounds exert effects via a common mechanism of action, there is a potential for interactions between DEHP and other phthalate esters. 

Standards Prepare individual solutions of a 1.25 mg/mL concentration of dioctyl, dibutyl, and dimethyl esters of phthalic acid by weighing 0.125 g of each ester into an individual 100-mL volumetric flask and diluting to volume with THF from the same lot as used in the solvent reservoir. Place 0.1 mL of benzene in another 100-mL volumetric flask and dilute to the mark with THF as before. 

---