Plasticizers, organic phosphates

Of interest is the manner in which cavities of the appropriate size are introduced into ion-selective membranes. These membranes typically consist of highly plasticized poly(vinyl chloride) (see Membrane technology). Plasticizers (qv) are organic solvents such as phthalates, sebacates, trimelLitates, and organic phosphates of various kinds, and cavities may simply be the excluded volumes maintained by these solvent molecules themselves. More often, however, neutral carrier molecules (20) are added to the membrane. These molecules are shaped like donuts and have holes that have the same sizes as the ions of interest, eg, valinomycin [2001-95-8] C H QN O g, and nonactin [6833-84-7] have wrap around stmctures like methyl monensin... 

Plasticizers/oils. These are added for several reasons (a) to improve the compatibility between SBR and the other additives (b) as extender (to reduce cost) (c) to soften the SBR (d) to change the wetting properties. The most common additives are organic phosphates, phthalate esters and aromatic hydrocarbon oils. 

Organic phosphates, phosphonates, and analogues are of interest in medicinal chemistry as drugs or prodrugs, and in toxicology mainly as plasticizers, insecticides, or warfare agents. Their breakdown by enzymatic routes has received marked attention since many years, but it is most unfortunate for the advancement of science that an unknown number of highly relevant results remain classified information. 

Because of the presence of the chlorine atom In every repeating unit PVC does not bum as readily as hope. When used as a plasticizer, tricresyl phosphate also contributes to flame retardancy. In contrast, the organic ester plasticizers, such as DOP, contribute to the combustibility of plasticized PVC Tricresyl phosphate is more toxic than organic esters, and DOP is more toxic than aliphatic esters, such as dioctyl adipate. 

Wood Plastic Composites (WPC) In WPC applications, it was claimed that the addition of organic phosphate, zinc borate/boric acid, sodium silicate, or ATH to milled rice straw with a resin binder can produce a fire-resistant board.65... 

Various organic plasticizers having boiling points over 300 °C are available, such as di(2-ethylhexyl) phthalate (4a), di(2-ethylhexyl) adipate (8), oligomers formed from dicarboxylic acids and diols with molecular weights ranging up to 3500, esters of tri-mellitic acid, epoxidised fatty acids or organic phosphates, such as tris(2-ethylhexyl) phosphate (9) or (2-ethylhexyl) diphenyl phosphate (10). Most phosphates also function as flame retardants and some, such as 10, are smoke suppressants as well (Meier, 1990). 

Flexible PVC (Table 15.6) is made by polymerizing at 40-55°C and then compounding with 20-80 PHR (parts per hundred of resin) of dioctyl phthalate and/or other monomeric liquid plasticizers (e.g., dioctyl adipate for low-temperature flexibility, oligomeric polyesters for permanence, organic phosphates for flame-retardance), plus a synergistic stabilizer system usually composed of barium or calcium soap, zinc soap, epoxidized fatty ester, and organic phosphite. 

TCP is used as a plasticizer in vinyl plastics, as a flame-retardant, and as an additive to extreme pressure lubricants. The main market for PVC-based products plasticized with organic phosphate esters is in the manufacture of automobile and other motor vehicle interiors in the USA. 

Empirical C21H21BO3 Formula (CH3CeH4)3B03 Properties Light amber liq. misc. with acetone, benzene, chloroform dens. 1.065 b.p. 385-395 C flash pt. 115.5 C ref. index 1.5480 (24 C) hydrolyzed by water Precaution Combustible Uses Plasticizer organic synthesis Tricresyl phosphate... 

Flammability is also a function of the plasticizer used. When phthalates are added to PVC, they reduce the total chlorine content, which reduces flame retardance. On the other hand, when organic phosphate esters are used as plasticizers, they actually increase flame-retardance (Sec. 5.7). This makes them particularly important in cellulosic plastics. 

Zinc stabilizer n. Any of a group of zinc soaps of fatty acids, usually formulated in combination with barium and calcium soaps and organic phosphates in plasticized PVC compounds. Wickson EJ (ed)... 

Low cost Light-colored or nonstaining stocks (including black stock) Low temperature service Heat resistance Petroleum oils, naphthenic and aromatic Ester plasticizers, chlorinated paraflins, or selected petroleum oils Ester plasticizers or cis-polybutadiene Poljrmeric plasticizers, chlorinated paraflins, polyester plasticizers, and low volatility petroleum oils Chlorinated paraflins and organic phosphate esters A polyether-[di(butoxy-ethoxy ethyl) formal] Ester, chlorinated paraflins, or poljmieric plasticizers... 

In poly(imide) (Pl)-based adhesive compositions that are particularly useful in flexible circuit applications, plasticizers are used (35). Organic phosphates in an amount from 15-35% are added, such as triphenyl and tricresyl phosphate. 

In general, plasticizers for PVC resins are esters of aliphatic and aromatic di and tricarboxcyhc acids and organic phosphates. High molecular weight alkylaromatic hydrocarbons, chlorinated aliphatic hydrocarbons and... 

Phosphorus content is a good indicator of properties of organic phosphates used as plasticizers. 

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. 

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