Home Physical Sciences Basic Classification and Definitions of Polymerization Reactions
Article Open Access

Basic Classification and Definitions of Polymerization Reactions

  • John B. Matson EMAIL logo
Published/Copyright: October 29, 2025
Download Article (PDF)
Become an author with De Gruyter Brill
Author Information
Chemistry International
From the journal Chemistry International Volume 47 Issue 4

This document provides recommendations addressing the long-standing dilemma of the wide variety of terms that are used to describe the two common classes of polymerization mechanisms in the scientific literature, which includes chemistry and polymer-science textbooks. It is an update of a 1994 IUPAC document on this topic and provides clarification and hierarchical structure regarding the basic classification and terminology describing polymerization reactions. The term step polymerization describes polymerizations in which growth occurs by reactions between monomer, oligomer, or polymer molecules of any length. We clearly denote here the two subclasses of step polymerization: additive step polymerization (synonym: polyaddition) and condensative step polymerization (synonym: polycondensation). The term chain polymerization describes polymerizations that proceed via a chain reaction with monomer molecules adding to active sites on polymer chains. Subclasses of chain polymerization include additive chain polymerization and condensative chain polymerization. The terms provide a logical and straightforward structure for describing the two common classes of polymerization mechanisms. Previously defined terms relevant to these two classes of polymerization reactions are also replicated in this Recommendation document.

Comments by 30 November 2025

https://iupac.org/recommendation/basic-classification-and-definitions-of-polymerization-reactions/

Published Online: 2025-10-29
Published in Print: 2025-10-01

©2025 by Walter de Gruyter Berlin/Boston

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Articles in the same Issue

  1. Can the “Right to Science” Restore Public Trust?
  2. The Future of Science in the Digital Age: Chemistry at a Crossroads
  3. Chemistry for a Fairer, Safer, and More Sustainable World
  4. Science at a Crossroads: Restoring Integrity and Public Trust
  5. Building Trust in Science: A Two-Way Commitment
  6. Science: A Truth Worth Defending
  7. Science Under Siege: Confronting the Hydra’s Many Heads
  8. Masthead - Full issue pdf
  9. Past President’s Column
  10. Chemistry at the Crossroads: Enabling Solutions for a Changing World
  11. Features
  12. IUPAC’s 2025 Top Ten Emerging Technologies in Chemistry
  13. Preventing spread of chemical weapons in an era of rapid technological change
  14. Why think philosophically about chemistry?
  15. Spotlight on IUPAC Young Observers
  16. Spotlight on IUPAC U.S. Young Observers
  17. IUPAC Wire
  18. IUPAC Launches Global Call to Action for Responsible Chemistry
  19. IUPAC Announces the 2025 Top Ten Emerging Technologies in Chemistry
  20. Actions Taken by IUPAC Council, Kuala Lumpur, Malaysia, July 2025
  21. Recognising Excellence: CCE 2026 Awards—Call for Nominations
  22. 2026 IUPAC-Richter Prize—Call for Nominations
  23. 2026 IUPAC–Soong Prize for Sustainable Chemistry—Call for Nominations
  24. 2026 IUPAC-Solvay International Award for Young Chemists—Call for Applicants
  25. Systems Thinking in Chemistry Education—Call for Papers
  26. Special issue IYQ in PAC
  27. In Memoriam
  28. Project Place
  29. Terminology for Dynamic Polymer Networks and Hydrogels
  30. Systems Thinking, Sustainability and Chemical Industry
  31. Small-Scale Chemistry Initiative in India
  32. Making an imPACt
  33. Definitions and preferred symbols for mass diffusion coefficients in multicomponent fluid mixtures including electrolytes (IUPAC Technical Report)
  34. IUPAC/CITAC guide: interlaboratory comparison of categorical characteristics of a substance, material, or object (IUPAC Technical Report)
  35. Blockchain technology: driving change in the scientific research workflow
  36. IUPAC Provisional Recommendations
  37. Basic Classification and Definitions of Polymerization Reactions
  38. Conference Call
  39. IUPAC 2025 in Kuala Lumpur Opened with Focus on Sustainability and Excellence
  40. Restoring Trust in Science: A Global Imperative
  41. Sustainable Practices for Promoting Diversity in Chemistry
  42. Green Chemistry for a Sustainable Future
  43. Advancing Scientific Terminology & Standards for the Digital Era—DUST Conference 2025
  44. Stockholm Declaration on Chemistry for the Future
  45. Mark Your Calendar
  46. Index
https://doi.org/10.1515/ci-2025-0423
Creative Commons
BY-NC-ND 4.0

Articles in the same Issue

  1. Can the “Right to Science” Restore Public Trust?
  2. The Future of Science in the Digital Age: Chemistry at a Crossroads
  3. Chemistry for a Fairer, Safer, and More Sustainable World
  4. Science at a Crossroads: Restoring Integrity and Public Trust
  5. Building Trust in Science: A Two-Way Commitment
  6. Science: A Truth Worth Defending
  7. Science Under Siege: Confronting the Hydra’s Many Heads
  8. Masthead - Full issue pdf
  9. Past President’s Column
  10. Chemistry at the Crossroads: Enabling Solutions for a Changing World
  11. Features
  12. IUPAC’s 2025 Top Ten Emerging Technologies in Chemistry
  13. Preventing spread of chemical weapons in an era of rapid technological change
  14. Why think philosophically about chemistry?
  15. Spotlight on IUPAC Young Observers
  16. Spotlight on IUPAC U.S. Young Observers
  17. IUPAC Wire
  18. IUPAC Launches Global Call to Action for Responsible Chemistry
  19. IUPAC Announces the 2025 Top Ten Emerging Technologies in Chemistry
  20. Actions Taken by IUPAC Council, Kuala Lumpur, Malaysia, July 2025
  21. Recognising Excellence: CCE 2026 Awards—Call for Nominations
  22. 2026 IUPAC-Richter Prize—Call for Nominations
  23. 2026 IUPAC–Soong Prize for Sustainable Chemistry—Call for Nominations
  24. 2026 IUPAC-Solvay International Award for Young Chemists—Call for Applicants
  25. Systems Thinking in Chemistry Education—Call for Papers
  26. Special issue IYQ in PAC
  27. In Memoriam
  28. Project Place
  29. Terminology for Dynamic Polymer Networks and Hydrogels
  30. Systems Thinking, Sustainability and Chemical Industry
  31. Small-Scale Chemistry Initiative in India
  32. Making an imPACt
  33. Definitions and preferred symbols for mass diffusion coefficients in multicomponent fluid mixtures including electrolytes (IUPAC Technical Report)
  34. IUPAC/CITAC guide: interlaboratory comparison of categorical characteristics of a substance, material, or object (IUPAC Technical Report)
  35. Blockchain technology: driving change in the scientific research workflow
  36. IUPAC Provisional Recommendations
  37. Basic Classification and Definitions of Polymerization Reactions
  38. Conference Call
  39. IUPAC 2025 in Kuala Lumpur Opened with Focus on Sustainability and Excellence
  40. Restoring Trust in Science: A Global Imperative
  41. Sustainable Practices for Promoting Diversity in Chemistry
  42. Green Chemistry for a Sustainable Future
  43. Advancing Scientific Terminology & Standards for the Digital Era—DUST Conference 2025
  44. Stockholm Declaration on Chemistry for the Future
  45. Mark Your Calendar
  46. Index
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Winner of the OpenAthens UX Award 2026
Winner of the OpenAthens UX Award 2026
Have an idea on how to improve our website?
Please write us.
© 2026 De Gruyter Brill
Downloaded on 6.3.2026 from https://www.degruyterbrill.com/document/doi/10.1515/ci-2025-0423/html
Scroll to top button