Precise determination of copolymer reactivity ratios by a single point method

Journal Article · Fri Oct 01 00:00:00 EDT 1982 · J. Polym. Sci., Polym. Lett. Ed.; (United States)

DOI:https://doi.org/10.1002/pol.1982.130201001· OSTI ID:6523603

Burfield, D R; Savariar, C M

Although the underlying theoretical basis for the evaluation of reactivity ratios has been known for several decades, improved methods of data treatment are of continuing interest. Newer computational methods offer increased precision and frequently permit the possibility of the use of high-conversion data through evaluation of an integrated form of the copolymer composition equation. However, despite the importance of these developments the ''sine qua non'' in copolymerization studies is the accurate analysis of copolymer composition, whether directly or indirectly through residual monomer analysis. Thus, Tidwell and Mortimer cite several examples of significant errors in compositional analysis and show that such deviations have a powerful influence on r/sub 1/, r/sub 2/ values. Use of computational methods described in this report permits the use of high-conversion data when using methods for evaluating copolymerization systems by using a large excess of one monomer. This enables the evaluation of (r) values from a single data point and, provided that a sensitive method is available for determination of M in the copolymer, also allows a unique opportunity to minimize errors arising from the copolymer analysis. The method is illustrated in this article through coplymerization studies with tritium-labeled methylvinylketone (MVK). Results for styrene copolymerization demonstrate that there is most probably no significant penultimate unit effect for the addition MVK to the polystyrene radical.

• Research Organization: Univ. of Malaya, Kuala Lampur, Malaysia
• OSTI ID: 6523603
• Journal Information: J. Polym. Sci., Polym. Lett. Ed.; (United States), Vol. 20:10
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
KETONES
COPOLYMERIZATION
LABELLING
STYRENE
TRITIUM
ISOTOPE EFFECTS
ACTIVATION ENERGY
METHACRYLATES
VINYL MONOMERS
AROMATICS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBOXYLIC ACID SALTS
CHEMICAL REACTIONS
ENERGY
HYDROCARBONS
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
MONOMERS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
POLYMERIZATION
RADIOISOTOPES
YEARS LIVING RADIOISOTOPES
400302* - Organic Chemistry- Isotope Effects- (-1987)