Preparation of Poly vinyl Alcohol

Preparation of Poly(vinyl alcohol) by the Alcoholysis of Poly(vinyl acetate)... 

Preparation of poly(vinyl alcohol-bis(allyloxy)methane)-poly(vinyl alcohol)... 

Fabini, M., Bobala, S., Rusina, M., Macho, V., Preparation of poly(vinyl alcohol) as the dispersant for suspension vinyl chloride polymerizations, Polymer 35 (1994) 2201. 

T. Nonaka, T. Ogata and S. Kurihara, Preparation of poly(vinyl alcohol)-graft-A-isopropylacrylamide copolymer membranes and permeation of solutes through the membranes, J. Appl. Polym. Sci., 1997, 66, 209 T. Ogata, S. Kurihara and T. Nonaka, Preparation and properties of poly(vinyl alcohol)-graft-A-isopropylacrylamide and other monomers terpolymer membranes, Nippon Kagaku Zasshi, 1995, 909-915. 

Direct preparation of poly(vinyl alcohol) would require an enol as the monomer. However, recall that most enols cannot be isolated because they spontaneously isomerize to the carbonyl tautomer (see Section 11.6). 

C.T. Lee, P.H. Kung, Y.D. Lee, Preparation of poly (vinyl alcohol)-chondroitin sulfate hydrogel as matrices in tissue engineering, Carbohydr. Polym. 61 (3) (2005) 348-354. 

Cho EB, Kim H, Kim D (2009) Effect of morphology and pore size of sulfonated mesoporous benzene-silicas in the preparation of poly(vinyl alcohol)-based hybrid nanocomposite membranes for direct methanol fuel cell application. J Phys Chem B 113 9770-9778... 

Ficek BJ, Peppas NA (1993) Novel preparation of poly (vinyl alcohol) microparticles without crosslinking agent for controlled drug delivery of proteins. J Control Release 27 259... 

Zhang Wei, Zhao Xinzhen, Zhang Zhennan, Xn Ynnxia, and Wang Xinping. Preparation of poly(vinyl alcohol)-hased membranes with controllable surface composition and bulk structures and their pervaporation performance. J. Membr. ScL 415-416 (2012) 504-512. 

Amirilargani M, Ghadimi A, Tofighy MA, Mohammadi T (2013) Effects of polyfallylamine hydrochloride) as a new functionalization agent for preparation of poly vinyl alcohol/ multiwalled carbon nanotubes membranes. J Membr Sci 447 315-324 Andrews R, Weisenberger MC (2004) Carbon nanotube polymer composites. Curr Opin Solid... 

Kurihara S, Ueno Y, Nonaka T. Preparation of poly(vinyl alcohol)-graft-N-isopropylacrylamide binary membranes with triphenylmethane leucocyanide and permeation of solutes through membranes. J Appl Polym Sci 1998 67 1931-1937. 

If a suitable monomer is present, grafts are grown from these initiating sites. This method has been applied by Kukani and Mehta to grafting polyacrylonitrile onto cellulose and by Iwakura and Imai to the preparation of poly(vinyl alcohol-gfra/t-methyl methacrylate). More recently, Parker et al have synthesized poly(vinyl alcohol- rq/t-vinylpyridine hydrochloride) and McCormick and Lin have grafted polyacrylamide chains onto starch. 

Jin, W. J., et al. (2007). A study on the preparation of poly(vinyl alcohol) nanofibers containing silver nanoparticles. Synthetic Metals, 157(10-12), 454-459. 

Analogously, poly(vinyl ketals) can be prepared from ketones, but since poly(vinyl ketals) are not commercially important, they are not discussed here. The acetalization reaction strongly favors formation of the 1,3-dioxane ring, which is a characteristic feature of this class of resins. The first of this family, poly(vinyl ben2al), was prepared in 1924 by the reaction of poly(vinyl alcohol) with ben2aldehyde in concentrated hydrochloric acid (2). Although many members of this class of resins have been made since then, only poly(vinyl formal) [9003-33-2] (PVF) and poly(vinyl butyral) [63148-65-2] (PVB) continue to be made in significant commercial quantities. 

Solution Polymerization. Solution polymerization of vinyl acetate is carried out mainly as an intermediate step to the manufacture of poly(vinyl alcohol). A small amount of solution-polymerized vinyl acetate is prepared for the merchant market. When solution polymerization is carried out, the solvent acts as a chain-transfer agent, and depending on its transfer constant, has an effect on the molecular weight of the product. The rate of polymerization is also affected by the solvent but not in the same way as the degree of polymerization. The reactivity of the solvent-derived radical plays an important part. Chain-transfer constants for solvents in vinyl acetate polymerizations have been tabulated (13). Continuous solution polymers of poly(vinyl acetate) in tubular reactors have been prepared at high yield and throughput (73,74). 

Poly(vinyl nitrate) has been prepared and studied for use in explosives and rocket fuel (104,105). Poly(vinyl alcohol) and sulfur trioxide react to produce poly(vinyl sulfate) (106—111). Poly(vinyl alkane sulfonate)s have been prepared from poly(vinyl alcohol) and alkanesulfonyl chlorides (112—114). In the presence of urea, poly(vinyl alcohol) and phosphoms pentoxide (115) or phosphoric acid (116,117) yield poly(vinyl phosphate)s. 

Org inic Esters. An unlimited number of organic esters can be prepared by reactions of poly(vinyl alcohol) employing standard synthesis (82,84). Chloroformate esters react with poly(vinyl alcohol) to yield poly(vinyl carbonates) (118). 

Poly(vinyl butyral), prepared by reacting poly(vinyl alcohol) with -butyraldehyde, finds wide appHcation as the interlayer in safety glass and as an adhesive for hydrophilic surfaces (161). Another example is the reaction of poly(vinyl alcohol) with formaldehyde to form poly(vinyl formal), used in the production of synthetic fibers and sponges (162). 

Hollow and porous polymer capsules of micrometer size have been fabricated by using emulsion polymerization or through interfacial polymerization strategies [79,83-84, 88-90], Micron-size, hollow cross-linked polymer capsules were prepared by suspension polymerization of emulsion droplets with polystyrene dissolved in an aqueous solution of poly(vinyl alcohol) [88], while latex capsules with a multihollow structure were processed by seeded emulsion polymerization [89], Ceramic hollow capsules have also been prepared by emulsion/phase-separation procedures [14,91-96] For example, hollow silica capsules with diameters of 1-100 micrometers were obtained by interfacial reactions conducted in oil/water emulsions [91],... 

Thermally reversible gels can be prepared from poly (vinyl alcohol) and alkali metal salts of o-hydroxybenzal derivatives having benzenoid groups at both ends 24). Colored gels can be obtained, depending on the type of ketone used (Figure 4). 

The property of thermal, reversible gelation is obtained by the addition of water-soluble proteins and protein degradation products to an aqueous solution of poly (vinyl alcohol) 2). Protein products such as albumin, gelatin, glue, a-amino acids, and their condensation products—diketopiperazines—may be used. A typical formulation for the preparation of a thermally reversible gel is ... 

Radiation Induced Reactions. Graft polymers have been prepared from poly(vinyl alcohol) by the irradiation of the polymer-monomer system and some other methods. The grafted side chains reported include acrylamide, acrylic acid, acrylonitrile, ethyl acrylate, ethylene, ethyl methacrylate, methyl methacrylate, styrene, vinyl acetate, vinyl chloride, vinyl pyridine and vinyl pyrrolidone (13). Poly(vinyl alcohols) with grafted methyl methacrylate and sometimes methyl acrylate have been studied as membranes for hemodialysis (14). Graft polymers consisting of 50% poly(vinyl alcohol), 25% poly(vinyl acetate) and 25% grafted ethylene oxide units can be used to prepare capsule cases for drugs which do not require any additional plasticizers (15). 

EDTA in water. Ru(bpy)2 + and its dicinnamate were immobilized in a membrane prepared from cinnamate of poly(vinyl alcohol) by photocrosslinking 51), and the immobilized complex sensitized the photoreduction of MV2 +. ... 

The physical properties of poly(vinyl alcohol) are highly correlated with the method of preparation. The final properties are affected hy the polymerization conditions of the parent poly(vinyl acetate), the hydrolysis conditions, drying, and grinding. Further, the term poly(vinyl alcohol) refers to an array of products that can be considered copolymers of vinyl acetate and vinyl alcohol. 

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