AbstractNMP (N‐methyl‐2‐pyrrolidone) and its mixtures with water have been investigated as solvents for PVA poly(vinyl alcohol). Judging from the higher exponent in the Mark‐Houwink equation, NMP appears to be a better solvent than water. The equation found isdocumentclass{article}pagestyle{empty}begin{document}$left eta right = 1.69 times 10^{ - 4} left( {M_v } right)^{0.79}$end{document}for solutions in NMP at 30°C. Although the viscosity of NMP–water mixtures goes through a maximum when the molar ratio of NMP to water is 1:2, the intrinsic viscosity for PVA exhibits neither a maximum nor a minimum in mixtures ranging from pure water to pure NMP. As in aqueous solutions, the intrinsic viscosity in NMP solutions decreases slightly with increasing temperatures from
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