Experimental methods and data evaluation procedures for the determination of radical copolymerization reactivity ratios from composition data (IUPAC Recommendations 2025)

Autzen, Anton A A

Beuermann, Sabine

Drache, Marco

Fellows, Christopher M

Harrisson, Simon

Van Herk, Alex M

Hutchinson, Robin A

Kajiwara, Atsushi

Keddie, Daniel J

Klumperman, Bert

Russell, Gregory T

Journal Article

en

Publication

Walter de Gruyter GmbH

Germany

10.1515/pac-2024-0235

une:1959.11/71405

This recommendation defines the preferred methodology for determining reactivity ratios from copolymer composition data using the terminal model for radical copolymerization. The method is based on measuring conversion (X) and copolymer composition (F) of three or more copolymerization reactions conducted with different initial monomer compositions (f₀). Both low and high conversion experiments can be combined, or alternatively only low conversion experiments can be used. The method provides parameter estimates, but can also reveal deviations from the terminal model and the presence of systematic errors in the measurements. Special attention is given to error estimation in F and construction of the joint confidence interval for the reactivity ratios. Previous experiments measuring f₀ − F (i.e., copolymer composition as a function of varying f₀) or f − X (i.e., how f varies with X in an experiment) can also be analyzed with this IUPAC recommended method. The influence of systematic errors in the measurements on the reactivity ratio determinations is addressed. The document has a broad significance in that it seeks to eradicate the use of incorrect methods and common mistakes in determining reactivity ratios in radical copolymerizations.

link

Pure and Applied Chemistry

1365-3075

0033-4545