Polyfvinyl alcohol structure

Poly(vinyl acetate) is an atactic material and is amorphous. Whilst the structure of polyfvinyl alcohol) is also atactic the polymer exhibits crystallinity and has essentially the same crystal lattice as polyethylene. This is because the hydroxyl groups are small enough to fit into the lattice without disrupting it. 

Poly(vinyl alcohol) has the structure 10.67. Poly(vinyl acetate) is the fully esterified derivative of polyfvinyl alcohol), in which the -OH groups are replaced by -OCOCH3 groups. As indicated in Table 10.5, commercial polyvinyl sizes are effectively copolymers of polyfvinyl acetate) and polyfvinyl alcohol) that vary in the degree of saponification of the ester groups. These products may comprise 100% of either polymer, or combinations of the two monomers in any proportions. Crotonic acid (2-butenoic acid), widely used in the preparation of resins, may also be a component. This compound exhibits cis-trans isomerism (Scheme 10.17). The solid trans form is produced readily by catalysed rearrangement of the liquid cis isomer. 

Hassan, C. M. and Peppas, N. A. Structure and Applications of Polyfvinyl alcohol) Hydrogels Produced by Conventional Crosslinking or by Freezing/Thawing Methods. Vol. 153, pp. 37-65. 

Polyfvinyl alcohol) is an important example. Inspection of the structure reveals that this is a typical alkene polymer but the monomer would have to be vinyl alcohol—the unstable enol of acetaldehyde. The way to make the polymer is to start with something else and only later... 

With a particular poly(vinyl alcohol) sample no periodic acid is consumed, within the limits of analytical aecuracy. This indicates no apparent (1,2-diol) cleavage. However, the viscosity average molecular weight of the sample decreased from 250,000 to 100,0(X), Explain these results in terms of the structures of po y(vinyl acetate) and polyfvinyl alcohol). [The analytical technique is described by P. J. Flory and F. S, Leutner, J. Polym. Set. 3,880 (1948) 5, 267(1950).]... 

Polystyrene is the name of a homopolymer made from the single monomer styrene. When the name of a monomer comprises two or more words, the name should be enclosed in parentheses, as in polyfmethyl methacrylate) or poly(4-bromostyrene) to identify the monomer more clearly. This method can result in several names for a given polymer thus, polyfethylene glycol) , poly(ethylene oxide) , and poly(oxirane) describe the same polymer. Sometimes, the name of a hypothetical monomer is used, as in polyfvinyl alcohol) . Even though a name like polyethylene covers a multitude of materials, the system does provide understandable names when a single monomer is involved in the synthesis of a single polymer. When one monomer can yield more than one polymer, e.g. 1,3-butadiene or acrolein, some sort of stiuctural notation must be used to identify the product, and one is not far from a formal structure-based name. 

Nakano, Y., Bin, Y, Bando, M. et al. 2007. Structure and mechanical properties of chitosan/polyfvinyl alcohol) blend films. Macromol Symp 258 63-81. 

Fergg F, Kell F, Quader H (2001) Investigations of the microscopic structure of polyfvinyl alcohol) hydrogels by confocal laser scanning microscopy. Colloid Polym Sci 279 61-67... 

The structure of poly(vinyl alcohol) is shown below. This polymer cannot be made by polymerizing its monomer. Why not How could polyfvinyl alcohol) be prepared from poly(vinyl acetate) ... 

Table 43 Structural and technical properties of polyfvinyl alcohol)-based weak acid cation exchangers.

Polsoirea, 99 Polsoirethane, 99 Poly(vinyl acetate), 199, 200 Poly(vinyl alcohol) (PVA), 9,20,94-5, 108, 110, 200, 202, 204, 258-9 analysis of dynamics, 261-2 aqueous system, 58 C CP/MAS NMR spectrum, 259-61 crosslink structure, 259-61 Poly(vinyl alcohol) (PVA)/sodium borate, self-correlation function, 205 Polyfvinyl alcohol) (PVA)-water gel, 57 Polyfvinyl chloride) (PVC), 109, 324 Poly(vinyl methylether) (PVME), 108, 245 Porod law, 212 Porod region, 196 Proportionality equations, 127 Protein gels, 288-90 Proteins, 282... 

Li, J., Suo, J.P., Deng, R.Z., 2010. Structure, mechanical, and swelling behaviors of polyfvinyl alcohol)/Si02 hybrid membranes. Journal of Reinforced Plastics and Composites 29, 618-629. 

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