Book contents
- Frontmatter
- Contents
- Preface
- 1 Chemistry and structure of reactive polymers
- 2 Physics and dynamics of reactive polymers
- 3 Chemical and physical analyses for reactive polymers
- 4 Chemorheological techniques for reactive polymers
- 5 Chemorheology and chemorheological modelling
- 6 Industrial technologies, chemorheological modelling and process modelling for processing reactive polymers
- Glossary of commonly used terms
- Index
3 - Chemical and physical analyses for reactive polymers
Published online by Cambridge University Press: 14 August 2009
- Frontmatter
- Contents
- Preface
- 1 Chemistry and structure of reactive polymers
- 2 Physics and dynamics of reactive polymers
- 3 Chemical and physical analyses for reactive polymers
- 4 Chemorheological techniques for reactive polymers
- 5 Chemorheology and chemorheological modelling
- 6 Industrial technologies, chemorheological modelling and process modelling for processing reactive polymers
- Glossary of commonly used terms
- Index
Summary
Monitoring physical and chemical changes during reactive processing
Reactive processing involves the production of a novel polymer as a result of chemical reactions that occur during the processing operation. These changes may be deliberate, as in functionalization, or inadvertent, as in chain scission due to undesired thermo- or mechano-chemistry. Section 1.4 gave the chemical changes to be expected when a thermoplastic polymer is subjected to elevated temperature for a period of minutes in the presence or absence of an oxidative atmosphere (Scott, 1993, Zweifel, 1998). For example, there will be the appearance of higher oxidation states of carbon such as in ether, alcohol, ketone and acid groups. These often accompany chain scission, which occurs during the free-radical-initiated oxidation chain reaction. In addition, there may be other chemical changes, such as grafting and functionalization, in which new chemical species are added to the polymer backbone in the course of the processing operation. The initiation of the oxidation, grafting or functionalization reactions will be through added initiator such as an organic peroxide and the novel chemistry will involve a monomer or other grafting agent, neither of which will necessarily be totally consumed during the reaction sequence. The measurement of the concentration profiles of these reagents as a function of time and, if possible, position in the reaction zone is crucial to the development of an understanding of the link between the chemical and rheological changes of the novel polymer system during processing.
- Type
- Chapter
- Information
- Chemorheology of PolymersFrom Fundamental Principles to Reactive Processing, pp. 195 - 320Publisher: Cambridge University PressPrint publication year: 2009