Reply to the Letter to the Editor

✍ Scribed by Rui Zhao; Chris Macosko

• Publisher: American Institute of Chemical Engineers
• Year: 2007
• Tongue: English
• Weight: 27 KB
• Volume: 53
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.11284

✦ Synopsis

Professor Han has three criticisms of our article: our viscosity equation has no rheological significance, our assumption of w = 0 is unjustified, and we failed to reference his 1991 article.

We agree that our viscosity equation is empirical. Viscosity does not enter into the model except as a measure of mixing of the two diffusing polymers. As stated on page 982 of our article we actually ''used the experimental data as a master curve, and a third-order spline interpolation method to find the viscosity of the blends at any concentration.''

We disagree that w , 0 is required for miscibility of two polymers. From Flory-Huggins theory with chains of equal length N, the criterion for miscibility is wN = 2. However,