ABSTRACT
Polyvinyl alcohol (PVOH) is a synthetic polymer made from the partial or full hydrolysis of polyvinyl acetate (PVA) to remove acetate groups. Addition polymerization of the vinyl alcohol monomer is not possible, because this species does not exist in the free state (Tang and Alavi 2011). PVOH is a hydrophilic polymer that dissolves in water over a wide range of temperatures (Goodship and Jacobs 2009; Hassan and Peppas 2000; Kadajji and Betageri 2011). This polymer is atactic and has the ability to crystallize, as opposed to PVA. Table 2.1 summarizes properties of PVOH in the different forms in which it is available commercially. Properties depend on factors such as molecular weight, degree of hydrolysis, water content, and the presence of additives (i.e., plasticizers) and, to some extent, on the method of manufacture. PVOH is nontoxic with a high barrier to oxygen and aromas, and it is resistant to oil, grease, and organic solvents. There are many different grades of PVOH that are produced by varying the molecular structure during the manufacturing process,
2.9 Complexes and Blends ............................................................................................................77 2.9.1 Metal Complexes ........................................................................................................77 2.9.2 PVOH-Iodine Complexes ...........................................................................................77 2.9.3 Blends, Composites, and Nanocomposites .................................................................77
