Polyvinyl acetate solubility

The effect of structural regularity on properties of polymers may be illustrated by the hydrolytic products of polyvinyl acetate (PVAc). PVAc is insoluble in water, but because of the presence of polar hydroxyl groups, partially hydrolyzed PVAc is soluble in water. 

Polyvinyl acetate phthalate (PYAP) dissolves at pH higher than 5 and is soluble in ethanol. Plasticizers that are used with PVAP include triethyl citrate, glyceryl triacetate, and acetyltriethyl citrate. 

This puts this polymer remote from the usual range of silicone rubbers, which have solubility parameters of about 15 (mJ m 3)l/2, and close to polycarbonates, which have a value of 19.4 (mJnT3)172, and nitrile rubbers and polyvinyl acetates, which are similar. 

The polyvinyl acetate and polybutyral polymers were useful for forming films, but the other materials were not. Polyvinyl alcohol is only soluble in water and not capable of being blended with other polymers. Also, any polymer with a large percentage of polyvinyl alcohol will absorb too much water and become permeable to bacteria. 

Poly(vinyl alcohol) - A water-soluble copolymer of -150,000 g/mole polymer from 99% hydrolysis of polyvinyl acetate. 

In a microorganism prone environment, it is preferable to protect a dressing with a preservative such as chlorhexidine to prevent the contamination of the dressing. It is necessary to consider the solubility of an agent in the liquid phase of the dressing during the selection of an antimicrobial agent. The formulated polyvinyl acetate and polybutyral materials were dissolved in ethanol that is also a solvent for chlorhexidine diacetate. The information (Block, 2001) in Table 2.12 provides solubilities of chlorhexidine compounds in different solvents. 

On the other hand polyvinyl acetate is very soluble in methanol even though the difference between the solubility parameters is 9.8. 

The solubilities of gases in polyvinyl-acetate. Trans. Faraday Soc. 54,40 (1958c). 

When the polymers were analyzed for their content of homopolymer, it was found that the acrylonitrile polymer is soluble in chlorobenzene and the vinyl chloride polymer in toluene. Since chlorobenzene is unable to dissolve polyacrylonitrile and toluene cannot dissolve poly (vinyl chloride), it must be assumed that no homopolymer has been formed. This has been verified by fractionations. It is possible to extract with methanol from the vinyl acetate polymer 33% of a substantially pure polyvinyl acetate with a vinyl acetate content of 95%. Hence, acrylo-... 

Polyvinyl Acetate occurs as a clear, water white to pale yellow, solid resin. It is prepared by the polymerization of vinyl acetate. After completion of polymerization, the resin is freed of traces of residual catalyst (usually a peroxide), monomer, and/or solvent by vacuum drying, steam sparging, washing, or any combination of these treatments. The resin is soluble in acetone, but it is insoluble in water. 

Many of the remarks made in the previous section concerning fibres can be applied to the analysis of plastics. Some polymers are soluble in organic solvents and samples may be prepared for direct aspiration into a flame in this way, e.g. MIBK is a suitable solvent for polyesters, polystyrene, polysiloxanes, cellulose acetate and butyrate dimethyl formamide for polyacrylonitrile, dimethyl acetamide for polycarbonates and polyvinyl chloride cyclohexanone for polyvinyl chloride and polyvinyl acetate formic acid for polyamides and methanol for polyethers. These organic solutions may alternatively be injected into a graphite furnace. Otherwise, polymers may be wet or dry ashed and the resultant ash dissolved in acid. An approach which is attracting increasing interest is the direct insertion of solid samples into a graphite furnace. 

Heintz, A. Lichtenthaler, R. N. Prausnitz, J. M., "Solubilities of Volatile Solvents in Polyvinyl Acetate, Polyvinyl Chloride, and Their Random Copolymers," Ber. Bunsenges. Phys. Chem., 83, 926 (1979). 

Polyvinyl alcohol (PVA) is a water-soluble polymer with a glass transition temperature, T, of 80 °C. Although its name implies a homopolymer stmcture, the structure of commercial PVA is a copolymer of vinyl alcohol and vinyl acetate as seen in Fig. 4.2. PVA is made by the incomplete hydrolysis of polyvinyl acetate... 

The characteristics of polyvinyl acetate phthalate from two sources have been compared values for molecular weight (60 700 47000), moisture content (3.74% 2.20%) and density (1.31 g/cm 1.37g/cm ) have been reported. The solubility of each polyvinyl acetate phthalate in a range of different solvents was described and scanning electron photomicrographs were produced to give evidence of the different polymer morphology. ... 

Solubility soluble in ethanol and methanol sparingly soluble in acetone and propan-2-ol practically insoluble in chloroform, dichloromethane, and water. In buffer solutions, polyvinyl acetate phthalate (200mg/L) is insoluble below pH 5 and becomes soluble at pH values above 5. Polyvinyl acetate pththalate shows a sharp solubility response with pH this occurs at pH 4.5-5.0, which is lower than for most other polymers used for enteric coatings. Solubility is also influenced by ionic strength. See Table III. 

CAS 9002-89-5. (-CH HOH-),. A water-soluble synthetic polymer made by alcoholysis of polyvinyl acetate. 

Solution—polymerization of monomers dissolved in solvents in which the polymer products are also soluble Lower viscosity than bulk and better heat transfer and mixing direct application of solution less reactor fouling Smaller reactor capacity than bulk high separation cost often inflammable and toxic solvents lower molecular weights SBR, polyvinyl acetate, polystyrene, acrylics... 

Polyester Acrylic copolymers Alkali soluble polyvinyl acetate Linear polyester Stymer (styrene - maleic anhydride coplymer) Gelatin... 

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