Analysis of the Competition between Cyclization and Linear Chain Growth in Kinetically Controlled A<sub>2</sub> + B<sub>2</sub> Step‐Growth Polymerizations Using Modeling Tools
Bibliographic record
Abstract
Abstract A mathematical model for the kinetics and chain length development in A2 + B2 step‐growth polymerization with competition between cyclization and linear chain growth is presented. The model requires two kinetic rate constants, one for the several reactions producing linear polymer molecules (k), and another one for chain length dependent cyclization (kc). The model describes well the qualitative behavior of the system, including the effects of initial monomer concentration and ratio of limiting to excess functional groups on degree of cyclization. The model is validated using two polymerization systems, a conventional A2 + B2 polymerization of hexamethylene diisocyanate (HDI) and poly(ethylene glycol) (PEG200), as well as the superacid catalyzed polyhydroxyalkylation of modified isatin and biphenyl. Four different kinetic rate constants for the four reactions producing linear polymer molecules are required in the second case.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".