Chap._600003 - The properties of PVOH are somewhat...

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6.3 Properties and Applications * PVAc Poly(vinyl acetate) by itself is not an attractive material, it is too brittle and shows too much cold flow to be useful in bulk form for rigid applications. The Tg is 28 o C, above which temperature the polymer is soft but not very rubber-like. In addition, extended exposure of PVAc to temperature above 70 oC results in discoloration and deterioration of mechanical properties, accompanied by elimination of acetic acid. * PVOH and EVOH
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Unformatted text preview: The properties of PVOH are somewhat dependent on the degree of alcoholysis. An important characteristic of PVOH is its solubility in water. The polymers with 87-89% alcoholysis are readily soluble in cold water. However, the completely hydrolysed PVOH are only dissolved in water by heating to above 85 o C, due to high crystallinity and high melting temperature (Tm= 230 o C). The hydrophilic PVOH is resistant to a very wide range of organic solvents....
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This note was uploaded on 10/16/2010 for the course MATSE 441 at Penn State.

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