Molar mass jumping

It is necessary to say that the molar masses of the calibration materials quoted by some suppliers may differ from the actual values. In other words, some commercial calibration materials may jump out from the calibration dependences because their molar mass determined by the producer is wrong. 

FIGURE 13.4 Using data from Figure 13.3, the fractional conversion of Am and VB are shown. A two-phase reaction occurs in which copolymer of Am and VB is produced up until 5500 s, after which homopolymers of Am form. Hence, a blend of copolyelectrolyte and Am homopolymer results. Also shown are the cumulative M and M. according to Equation 11.7. The mass of the polymer chains jumps up once the final Am homopolymerization period begins. Reprinted (adapted) with permission from Alb AM, Paril A, Catalgil-Giz H, Giz A, Reed WF. Evolution of composition, molar mass, and conductivity during the free radical copolymerization of polyelectrolytes. J Phys Chem B 2007 111 8560-8566. 2007 American Chemical Society. 

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