Vinyl polymers solubility

Water-Soluble Films. Water-soluble films can be produced from such polymers as poly(vinyl alcohol) (PVOH), methylceUulose, poly(ethylene oxide), or starch (qv) (see Cellulose ethers Polyethers Vinyl polymers). Water-soluble films are used for packaging and dispensing portions of detergents, bleaches, and dyes. A principal market is disposable laundry bags for hospital use. Disposal packaging for herbicides and insecticides is an emerging use. 

Almost all synthetic binders are prepared by an emulsion polymerization process and are suppHed as latexes which consist of 48—52 wt % polymer dispersed in water (101). The largest-volume binder is styrene—butadiene copolymer [9003-55-8] (SBR) latex. Most SBRlatexes are carboxylated, ie, they contain copolymerized acidic monomers. Other latex binders are based on poly(vinyl acetate) [9003-20-7] and on polymers of acrylate esters. Poly(vinyl alcohol) is a water-soluble, synthetic biader which is prepared by the hydrolysis of poly(viayl acetate) (see Latex technology Vinyl polymers). 

Functional derivatives of polyethylene, particularly poly(vinyl alcohol) and poly(acryLic acid) and derivatives, have received attention because of their water-solubility and disposal iato the aqueous environment. Poly(vinyl alcohol) is used ia a wide variety of appHcations, including textiles, paper, plastic films, etc, and poly(acryLic acid) is widely used ia detergents as a builder, a super-absorbent for diapers and feminine hygiene products, for water treatment, ia thickeners, as pigment dispersant, etc (see Vinyl polymers, vinyl alcohol polymers). 

To obtain a high viscosity at a much lower clay concentration, certain water-soluble vinyl polymers called clay extenders can be used. In addition to increasing the yield of sodium montmorillonite, clay extenders serve as flocculants for other clay solids. The flocculated solids are much easier to separate using solids control equipment. 

Organic peroxide are used to polymerise the esters by solvent or emulsion polymerisation. They form tough and pliable film. They are also used as plasticising agents for vinyl polymers. The polymer is soluble in benzene, toluene, chloroform, ethylene dichloride, ethyl acetate, etc. 

These soluble catalysts are able to give vinyl polymers that have increased stereogeometry with respect to tacticity as well as allowing the growing chains to form more precise helical structures. Further, the homogeneity of the catalytic sites also allows for the production of polymers with narrow molecular weight spreads. ... 

Grafting and Stabilizers. The degree of grafting of poly(vinyl acetate) (PVAc.) on poly(vinyl alcohol) (PVA) and other stabilizers during emulsion polymerization strongly affects latex properties such as viscosity, rheology, and polymer solubility. 

Incorporation of carboxyl groups in vinyl polymers (J) and polyolefins (1, 7) improves the adhesion of these polymers to various materials. However, many of these carboxylated polymers, particularly the carboxylated polyolefins, have limited solubility in volatile, lacquer-type solvents such as butyl acetate or methyl ethyl ketone and thus are limited in their ability to improve the adhesion of coatings applied from solvents. Carboxylated polyesters that are soluble in these solvents can be prepared. We were therefore interested in determining the effects of structure and carboxyl content on the adhesion of coatings of various classes of polymers blended with carboxylated polyesters. 

Poly(vinyl alcohol) used to manufacture the poly(vinyl acetal)s is made from poly(vinyl acetate) homopolymer (see Vinyl polymers, vinyl alcohol polymers Vinyl POLYMERS, VINYL ACETATE POLYMERS). Hydrolysis of poly(vinyl acetate) homopolymer produces a polyol with predominantly 1,3-glycol units. The polyol also contains up to 2 wt % 1,2-glycol units that come from head-to-head bonding during the polymerization of vinyl acetate monomer. Poly(vinyl acetate) hydrolysis is seldom complete, and for some applications, not desired. For example, commercial PVF resins may contain up to 13 wt % unhydrolyzed poly(vinyl acetate). Residual vinyl acetate units on the polymer help improve resin solubility and processibility (15). On the other hand, the poly (vinyl alcohol) preferred for commercial PVB resins has less than 3 wt % residual poly (vinyl acetate) units on the polymer chain. 

The solubility of the vinyl polymer in the epoxy resins will depend on the molecular weight and grade of vinyl used. Polyvinyl esters can be dissolved in liquid epoxy resins that are heated to about 100°C or in melted solid epoxy resins. However, most epoxy-vinyl blends are normally prepared via solvent solution. 

In the examples presented below, polymer-paper systems are examined for cases where there is complete impregnation of the substrate to form what behaves as a single component (poly(vinyl alcohol), soluble nylon, and Regnal) for cases where penetration is limited and the polymer and substrate behave in a generally separate manner (glues) and for cases where a range of behaviors—from apparent interactive to apparent independent—is observed although penetration is limited (poly-(vinyl acetates)). 

Polyvinyl alcohol is a vinyl polymer with a carbon-carbon backbone similar to other polymers such as polyethylene and polystyrene and is widely used as a water-soluble biodegradable polymer in the manufacture of delivery systems for fertilizers, pesticides and herbicides and is also used to manufacture containers and films. To date, only bacteria have been described as causing biodegradation of polyvinyl alcohols with some causing complete degradation of the polymer (see Shimao, 2001 for review). 

Merk, W. Lichtenthaler, R. N. Prausnitz, J. M., "Solubilities of Fifteen Solvents in Copolymers of Poly(Vinyl- Acetate) and Poly(Vinyl Chloride) from Gas-Liquid Chromatography. Estimation of Polymer Solubility Parameters," J. Phys. Chem., 84, 1694 (1980). 

A new process from the paint industry may have application for the suspension coating of pesticide crystals [25]. Low molecular weight water-soluble vinyl polymer chains are synthesized and the process stopped with a terminal vinyl group on each polymer chain. Hydrophobic acrylic monomers are then idded to create the hydrophobic strongly adsorbing backbone polymer. As each water-soluble polymer terminal vinyl group reacts with the growing hydrophobic backbone polymer it becomes inserted like a tooth on a comb. Indeed, these polymer structures are referred to as comb polymers. 

In this process, the monomer and iniliator are soluble in the continuous phase and the polymer particles, which precipitate as they are produced, are stabilized against coagulation by dispersants that comprise di fferent segments that are respectively soluble and insoluble in the continuous phase. Dispersion polymerizations have been used successfully as an alternative to solution polymerization of vinyl polymers for application as surface coatings. In that case the diluents are usually aliphatic hydrocarbons, and the process acronym is NAD [for nonaqueous dispersion]. 

Poly-VCy can form a stable complex with polyguanylic add (pdy G) and polyinosic add (poly I) in water-propylene glycol solution. However, die structure of the complex appears to be irregular. Poly-9-vinylhypoxanthine tends to produce the complex to a lesser extent as compared with the other vinyl polymers, probably due to its low solubility ... 

Figure 3. Solubility characteristics of typical vinyl polymers in MEK (Brook-...

Much has been written about ketones, as a class, as excellent solvents for vinyl polymers (7,8). Aside from solubility of the solvent, we also must consider its volatility characteristics (evaporation rate), flash point, boiling range, etc. With the high solubility type polymers, we have wide latitude with respect to selecting the ketone that will balance these properties against solution solids. This is evident in the next figures. 

Many esters such as butyl acetate and ethyl acetate are used as solvents for vinyl polymers. Figure 19 shows the solubility properties of a carboxyl containing terpolymer in various acetate solvents. These esters can also be used as diluents or to alter evaporation rates in mixed solvent systems. If a primary solvent such as a ketone is present, very high solids can be obtained. 

---