Vinyl acetate phthalate

The most commonly used polymers are cellulose acetate phthalate [9004-38-0] (CAP), poly(vinyl acetate phthalate) [34481-48-6] (PVAP), hydroxypropylmethyl-ceUulosephthalate [71138-97-1] (HPMCP), and polymethacrylates (111) (see Cellulose esters). Acrylate copolymers are also available (112). Eigure 11 shows the dissolution behavior of some commercially available enteric materials. Some manufacturers supply grades designed to dissolve at specific pH values with increments as small as 0.5 pH unit (113). 

In the past, the initial layers of coating (the sealing coat) were achieved by applying one or two coats of shellac. However, due to the variability between batches of this material, PVP-stabilized types of shellac or other polymeric materials, such as cellulose acetate phthalate (CAP) and poly(vinyl acetate phthalate) (PVAP), are now more popular. It should be appreciated that a fine balance must exist between minimizing the thickness of the sealing coat and providing an adequate moisture barrier. 

Hydroxypropyl methylcellulose phthalate (HPMCP) Poly(methacrylic acid-co-methyl methacrylate) Poly(vinyl acetate phthalate) (PVAP)... 

PVAc/Ph Poly(vinyl acetate)/phthalate C. E. Frosst Company... 

Successful results have been obtained (Renfrew and Chaney, 1946) with ethyl formate methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec.-butyl and iso-amyl acetat ethyleneglycol diacetate ethyl monochloro- and trichloro-acetates methyl, n-propyl, n-octyl and n-dodecyl propionates ethyl butyrate n-butyl and n-amyl valerates ethyl laurate ethyl lactate ethyl acetoacetate diethyl carbonate dimethyl and diethyl oxalates diethyl malonate diethyl adipate di-n-butyl tartrate ethyl phenylacetate methyl and ethyl benzoates methyl and ethyl salicylates diethyl and di-n-butyl phthalates. The method fails for vinyl acetate, ieri.-butyl acetate, n-octadecyl propionate, ethyl and >i-butyl stearate, phenyl, benzyl- and guaicol-acetate, methyl and ethyl cinnamate, diethyl sulphate and ethyl p-aminobenzoate. 

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. 

Tables 7 and 8 give properties of some diaHyl esters. DimethaHyl phthalate [5085-00-7] has been copolymerized with vinyl acetate and benzoyl peroxide, and reactivity ratios have been reported (75).

Although they lack commercial importance, many other poly(vinyl acetal)s have been synthesized. These include acetals made from vinyl acetate copolymerized with ethylene (43—46), propjiene (47), isobutjiene (47), acrylonitrile (48), acrolein (49), acrylates (50,47), aHyl ether (51), divinyl ether (52), maleates (53,54), vinyl chloride (55), diaHyl phthalate (56), and starch (graft copolymer) (47). 

Other large-volume esters are vinyl acetate [108-05-4] (VAM, 1.15 x 10 t/yr), methyl methacrylate [80-62-6] (MMA, 0.54 x 10 t/yr), and dioctyl phthalate [117-81-7] (DOP, 0.14 x 10 t/yr). VAM (see Vinyl polymers) is produced for the most part by the vapor-phase oxidative acetoxylation of ethylene. MMA (see Methacrylic polymers) and DOP (see Phthalic acids) are produced by direct esterification techniques involving methacryHc acid and phthaHc anhydride, respectively. 

Plasticizers. Plasticizers are materials that soften and flexibilize inherently rigid, and even britde polymers. Organic esters are widely used as plasticizers in polymers (97,98). These esters include the benzoats, phthalates, terephthalates, and trimeUitates, and aUphatic dibasic acid esters. Eor example, triethylene glycol bis(2-ethylbutyrate) [95-08-9] is a plasticizer for poly(vinyl butyral) [63148-65-2] which is used in laminated safety glass (see Vinyl POLYMERS, poly(vinyl acetals)). Di(2-ethyUiexyl)phthalate [117-81-7] (DOP) is a preeminent plasticizer. Variation of acid and/or alcohol component(s) modifies the efficacy of the resultant ester as a plasticizer. In phthalate plasticizers, molecular sizes of the alcohol moiety can be varied from methyl to tridecyl to control permanence, compatibiUty, and efficiency branched (eg, 2-ethylhexyl, isodecyl) for rapid absorption and fusion linear (C6—Cll) for low temperature flexibiUty and low volatility and aromatic (benzyl) for solvating. Terephthalates are recognized for their migration resistance, and trimeUitates for their low volatility in plasticizer appHcations. 

Vinyl polymers [polystyrene, PVC, polyethylene, polypropylene, poly(vinyl acetate), poly(vinyl alcohol), polyacrylonitrile] -1920 Packaging, tubing, household goods, records, carpets, toys, water based paint, adhesives, varnishes Phthalate esters, poly(vinyl alcohol) ... 

Figure 12.11 Pyrograms of a PVAc paint containing external plasticizers (a), and of a vinyl acetate/VeoVa copolymer (b). Peak assignments 1, acetic acid, 2, benzene, 3, butyl acetate, 4, butyl benzoate, 5, bis(2 methylpropyl) phthalate, 6, dibutylphthalate, 7, branched acrylates ranging from C7 to C9...

Adding plasticizer, like dioctyl phthalate, is generally accomplished by mechanical methods. Permanent or chemical plasticization can be done by copolymerization of VCM with monomers such as vinyl acetate, vinylidene chloride, methyl acrylate, or methyl rhethacrylate. Comonomer levels vary from 5-40%. The purpose of the co-polymers, of course, is to change the properties such as softening point, thermal stability, flexibility, tensile strength, and solubility. 

Plasticizers. Compounds added to high molecular weight polymers to give them flexibility, softness, and stretch. Plasticizers can be added mechanically at the compounding or shaping stage or chemically by copolymerization. For example, dioctyl phthalate is mechanically added to PVC vinyl acetate is copolymerized with PVC. Plasticizer content can vary from 5—40%. 

EINECS 203-468-6, see Ethylenediamine EINECS 203-470-7, see Allyl alcohol EINECS 203-472-8, see Chloroacetaldehyde EINECS 203-481-7, see Methyl formate EINECS 203-523-4, see 2-Methylpentane EINECS 203-528-1, see 2-Pentanone EINECS 203-544-9, see 1-Nitropropane EINECS 203-545-4, see Vinyl acetate EINECS 203-548-0, see 2,4-Dimethylpentane EINECS 203-550-1, see 4-Methyl-2-pentanone EINECS 203-558-5, see Diisopropylamine EINECS 203-560-6, see Isopropyl ether EINECS 203-561-1, see Isopropyl acetate EINECS 203-564-8, see Acetic anhydride EINECS 203-571-6, see Maleic anhydride EINECS 203-576-3, see m-Xylene EINECS 203-598-3, see Bis(2-chloroisopropyl) ether EINECS 203-604-4, see 1,3,5-Trimethylbenzene EINECS 203-608-6, see 1,3,5-Trichlorobenzene EINECS 203-620-1, see Diisobutyl ketone EINECS 203-621-7, see sec-Hexyl acetate EINECS 203-623-8, see Bromobenzene EINECS 203-624-3, see Methylcyclohexane EINECS 203-625-9, see Toluene EINECS 203-628-5, see Chlorobenzene EINECS 203-630-6, see Cyclohexanol EINECS 203-632-7, see Phenol EINECS 203-686-1, see Propyl acetate EINECS 203-692-4, see Pentane EINECS 203-694-5, see 1-Pentene EINECS 203-695-0, see cis-2-Pentene EINECS 203-699-2, see Butylamine EINECS 203-713-7, see Methyl cellosolve EINECS 203-714-2, see Methylal EINECS 203-716-3, see Diethylamine EINECS 203-721-0, see Ethyl formate EINECS 203-726-8, see Tetrahydrofuran EINECS 203-729-4, see Thiophene EINECS 203-767-1, see 2-Heptanone EINECS 203-772-9, see Methyl cellosolve acetate EINECS 203-777-6, see Hexane EINECS 203-799-6, see 2-Chloroethyl vinyl ether EINECS 203-804-1, see 2-Ethoxyethanol EINECS 203-806-2, see Cyclohexane EINECS 203-807-8, see Cyclohexene EINECS 203-809-9, see Pyridine EINECS 203-815-1, see Morpholine EINECS 203-839-2, see 2-Ethoxyethyl acetate EINECS 203-870-1, see Bis(2-chloroethyl) ether EINECS 203-892-1, see Octane EINECS 203-893-7, see 1-Octene EINECS 203-905-0, see 2-Butoxyethanol EINECS 203-913-4, see Nonane EINECS 203-920-2, see Bis(2-chloroethoxy)methane EINECS 203-967-9, see Dodecane EINECS 204-066-3, see 2-Methylpropene EINECS 204-112-2, see Triphenyl phosphate EINECS 204-211-0, see Bis(2-ethylhexyl) phthalate EINECS 204-258-7, see l,3-Dichloro-5,5-dimethylhydantoin... 

Verton D, see 2,4-D Verton 2D, see 2,4-D Verton 2T, see 2,4,5-T Vertron 2D, see 2,4-D Vestinol 80, see Bis(2-ethylhexyl) phthalate Vestrol, see Trichloroethylene Vetiol, see Malathion Vetox, see Carbaryl Vidon 638, see 2,4-D Vinegar acid, see Acetic acid Vinegar naphtha, see Ethyl acetate Vinicizer 85, see Di- octyl phthalate Vinnapas 850, see Vinyl acetate Vinyl acetate H.Q., see Vinyl acetate Vinyl alcohol 2,2-dichlorodimethyl phosphate, see Dichlorvos... 

Acetamido-4-amino-6-chloro-s-triazine, see Atrazine Acetanilide, see Aniline, Chlorobenzene, Vinclozolin Acetic acid, see Acenaphthene, Acetaldehyde, Acetic anhydride. Acetone, Acetonitrile, Acrolein, Acrylonitrile, Aldicarb. Amyl acetate, sec-Amyl acetate, Bis(2-ethylhexyl) phthalate. Butyl acetate, sec-Butyl acetate, ferf-Butyl acetate, 2-Chlorophenol, Diazinon. 2,4-Dimethylphenol, 2,4-Dinitrophenol, 2,4-Dinitrotoluene, 1,4-Dioxane, 1,2-Diphenylhydrazine, Esfenvalerate. Ethyl acetate, Flucvthrinate. Formic acid, sec-Hexyl acetate. Isopropyl acetate, Isoamyl acetate. Isobutyl acetate, Methanol. Methyl acetate. 2-Methvl-2-butene. Methyl ferf-butvl ether. Methyl cellosolve acetate. 2-Methvlphenol. Methomvl. 4-Nitrophenol, Pentachlorophenol, Phenol. Propyl acetate. 1,1,1-Trichloroethane, Vinyl acetate. Vinyl chloride Acetoacetic acid, see Mevinphos Acetone, see Acrolein. Acrylonitrile. Atrazine. Butane. 

Pan, I.-C., Tang, M., and Chen, Y.-P. Densities and viscosities of binary liquid mixtures of vinyl acetate, diethyl oxalate, and dibutyl phthalate with normal alkanols at 303.15 K, J. Chem. Eng. Data, 45(6) 1012-1015, 2000. 

The work function of the rubbing surfaces and the electron affinity of additives are interconnected on the molecular level. This mechanism has been discussed in terms of tribopolymerization models as a general approach to boundary lubrication (Kajdas 1994, 2001). To evaluate the validity of the anion-radical mechanism, two metal systems were investigated, a hard steel ball on a softer steel plate and a hard ball on an aluminum plate. Both metal plates emit electrons under friction, but aluminum produced more exoelectrons than steel. With aluminum, the addition of 1% styrene to the hexadecane lubricating fluid reduced the wear volume of the plate by over 65%. This effect considerably predominates that of steel on steel. Friction initiates polymerization of styrene, and this polymer formation was proven. It was also found that lauryl methacrylate, diallyl phthalate, and vinyl acetate reduced wear in an aluminum pin-on-disc test by 60-80% (Kajdas 1994). 

New modified polymeric electrodes selective to procaine and other local anaesthetic compounds were reported [72]. The electrode was constructed by incorporating the ion-pair complex of procaine with tungsto-phosphoric acid into ethylene-vinyl acetate copolymer. Best results were obtained with 1 1 nitrobenzene-dioctyl phthalate as a plasticizer. The calibration graph was linear fi om 18 p to 10 mM of procaine. When these electrodes were applied to the determination of the drug in pharmaceutical formulations, the recoveries were found to be quantitative. 

Phthalate, Butyl Benzyl Butyl Benzyl Phthalate Phthalate, Dibutyl Dibutyl Phthalate, n Phthalate, Diethylhexyl Diethylhexyl Phthalate Phthalate, Dimethyl Dimethyl Phthalate Phthalate, Dioctyl Di-n-octyl Phthalate Vinyl Acetate Ethers Fluoride Ion Glycols... 

Intractable polymers, such as polyvinyl chloride (PVC), may be flexibilized, to some extent, by the formation of copolymers, such as the copolymers of vinyl chloride and vinyl acetate or octyl acrylate, or by the addition of nonvolatile low-molecular-weight compounds (plasticizers) having solubility parameters similar to those of the polymer. Thus PVC is plasticized by the addition of dioctyl phthalate. The flexibility of these products is proportional to the amount of plasticizer added. Copolymers, such as the vinyl chloride-vinyl acetate copolymer, require less plasticizer to obtain the same degree of flexibility. 

Table VII gives Tc values for solutions of PVC and poly (vinyl acetate) in a series of dialkyl phthalates (34).

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