Polymeric plasticizer

Plasticizers. Monomeric (mol wt 250—450) plasticizers (qv) are predominantiy phthalate, adipate, sebacate, phosphate, or trimeUitate esters. Organic phthalate esters like dioctyl phthalate (DOP) are by far the most common plasticizers in flexible PVC. Phthalates are good general-purpose plasticizers which impart good physical and low temperature properties but lack permanence in hot or extractive service conditions and are therefore sometimes called migratory plasticizers. Polymeric plasticizers (mol wt up to 5000 or more) offer an improvement in nonmigratory permanence at a sacrifice in cost, low temperature properties, and processibiHty examples are ethylene vinyl acetate or nitrile polymers. 

Several examples of ion-selective electrodes with ionophores covalently attached to a self-plasticized polymeric matrix have been reported in the literature. For instance, a Ca-selective electrode with the ionophore attached to a methylmethacrylate-co-decyl methacrylate backbone was developed recently [91]. Ion exchangers such as the dodecacarborane anion have been anchored to the polymeric backbone, with grafted dodecarborane showing greatly improved retention in the polymeric phase [88],... 

Composite rocket propellants are two-phase mixtures comprising a crystalline oxidizer in a polymeric fuel/binder matrix. The oxidizer is a finely-dispersed powder of ammonium perchlorate which is suspended in a fuel. The fuel is a plasticized polymeric material which may have rubbery properties (i.e. hydroxy-terminated polybutadiene crosslinked with a diisocyanate) or plastic properties (i.e. polycaprolactone). Composite rocket propellants can be either extruded or cast depending on the type of fuel employed. For composite propellants which are plastic in nature, the technique of extrusion is employed, whereas for composite propellants which are rubbery, cast or extruded techniques are used. 

Laboratory containers are usually made from glass or plastic. Both materials are sources of aluminum. Aluminum oxide is a glass constituent, and plastics can content traces of aluminum due to the use of aluminum compounds as catalysts in many plastic polymerization processes. Other sources of aluminum resulting from sample handling are elastomeric materials. Table 5 presents the aluminum content of different raw materials used in manufacturing labware. 

Composite rocket propeiiants. This type of propellant contains two-phase mixtures with a aystalhne oxidizer in a polymeric fuel or binder matrix. The finely dispersed powder of ammonium perchlorate suspended in a fuel is the oxidizer. The fuel is a plasticized polymeric material such as hydroxy-terminated polybutadiene cross-linked with a diisocyanate (rubber ts e) or carboxy-terminated polybutadiene (plastic type) [4]. 

Surelease. a product of Colorcon. is produced by first melt extruding ethylcellulose with oleic acid and dibutyl sebacate (DBS) (or fractionated coconut oil) to form a molten plasticized polymeric blend. This molten blend of plasticized ethylcellulose is then introduced into an ammoniated water solution under high shear and pressure to disperse small droplets of plasticized ethylcellulose into the water phase (67). Ammonium oleate is produced in situ during this emulsification process to stabilize the colloidal ethylcellulose particles (67). Additional purified water is then added to reduce the final solids content of the pseudolatex dispersion to 25%. The Surelease coating system does not contain an ionic surfactant, and therefore does not exhibit the pH-dependent drug relea.se observed with Aquacoat ECD (66),... 

In addition to being an efficient and reliable extraction technique for the qualitative analysis of additives from a variety of plastic/polymeric matrices, there are additional applications where this technique can be used to provide information on the sample matrix. Sequentially increasing the... 

Keywords Antioxidants, Emulsifiers, Initiators, Integrated product policy. Lubricants, Plasticizers, Polymerization, Protective colloids. Renewable resources. Stabilizers, Surfactants, Sustainability... 

Semicrystalline Plastic - A plastic (polymeric) material characterized by localized regions of crystallinity. See also Amorphous Polymer. 

Standard and engineered columns feature removable frit plates for easy replacement, in order to cleaning purpose or product change. Frit plates are available within a range of material and frit pore sizes from 2 to 75 pm. The materials used could be plastic (polymeric) or metal. 

Materials having the highest thermal conductivities are the metals, metal alloys, and some ceramics while plastics, polymeric materials, and glasses have the lowest thermal conductivities. 

The plastics polymerize after entering a mold. Mixing two or more components (additives, fillers, and reinforcements) in the proper chemical ratio is accomplished by a high-pressure impingement-type mixing head. This mix is directed into the mold cavity at low pressure, where it chemically reacts to form a plastic. The components are mixed together at a given ratio and then directed or basically poured into a mold under controlled temperature, pressure, and rate of flow. They polymerize and cure in... 

Ken-React QB 012 Ken-React QB 321 Ken-React QB 521 plasticizer, polymeric coatings Multiwax 180-M Multiwax W-145A Multiwax W-835 plasticizer, polymers Admex 523 Albrite Tributyl Phosphate Butyl cyclohexyl phthalate Castor oil. 

Elastomers can be reinforced, or made tougher, by the addition of very small particles, typically finely dispersed carbon blacks or silicas. Similar types of reinforcement in elastomers can be brought about by the addition of a plastic polymeric phase (Sections 4.4 and 8.4) or the inclusion of polystyrene latexes. 

Storage Hygroscopic, deliq. keepwell closed Uses Catalyst for plastics polymerization in pyrotechnics in cone, of nitric acid Manuf./Distrib. Aldrich http //www.sigma-aidrich.com, Fluka http //www.sigma-aidrich.com, Markinter... 

Empirical C17H28O8S4 Formula C(CH200CCH2CH2.SH)4 Properties Liq. insol. in water m.w. 488.70 dens. 1.28 kg/l b.p. 275 C (1 mm) flash pt. > 110 C Uses Crosslinking agent and stabilizer for radiation-cured plastics polymerization modifier... 

Figure 8.7 shows that the conversion of monomers in photopolymerization of PMMA-acrylate increases with the amount of the plasticizer. Polymerization rate and conversion are affected by plasticizer. Figure 8.8 shows more complex behavior attributed to cure of epoxy oligomers. With very small additions of plasticizer (up to 1%) cure rate increases. This may be explained by decreasing the activation energy due to formation of complexes. Further increase in plasticizer concentration reduces rate because of dilution effect and complexing with proton donors which inhibits reaction. Comparison of results shows that addition of a plasticizer is more complex, as commonly thought, than the simple reduction in viscosity by addition of inert liquid. 

Sulfur dioxide has also been reported to plasticize polymeric membranes, which produces a more rubbery material and increases the diffusivity of penetrant gases [26-28]. Plasticization also reduces the mechanical integrity of the membrane, meaning it is more likely the membrane will rupture. However, plasticization is a strongly pressure dependent phenomenon, for example it has been reported in polyvinylidene membranes to occur at SO2 pressures greater than 10 psi [29]. For many of the processes in carbon capture, such high partial pressures of SO2 are not observed (Table 11.1), and therefore only minor plasticization by SO2 is likely to occur. 

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