Novel Cationic Macromonomers by Living Anionic Polymerization of (Dimethylamino)ethyl Methacrylate
Bibliographic record
Abstract
Water-soluble cationic macromonomers of (dimethylamino)ethyl methacrylate (DMAEMA) with terminal diallylmethylammonium or allylmethylphenylammonium group were synthesized by nitrogen anion (nitroanion) initiated living anionic polymerization of DMAEMA and subsequent quaternization. The initiators, lithium diallyamide and lithium allylphenylamide, were prepared by the reaction of corresponding N-substituted allylamine with butyllithium. The substituents on the nitroanion had a significant effect on the initiation efficiency. The initiator efficiencies of lithium allylamide, diallylamide, and allylphenylamide increased by the order 0 < 25% < 79% at −78 °C. The low initiator efficiency of lithium diallylamide was due to the reaction of the nitroanion with carbonyl groups in the monomer and polymer and could not be improved by optimizing polymerization conditions. A capping method using dimethylacrylamide (DMA) or tert -butyl methacrylate (tBMA) was then developed to modify the lithium diallylamide and thereby increased initiator efficiency. The DMA or tBMA capped lithium diallylamide had an initiator efficiency higher than 0.90, producing polymers with predicted molecular weight and nearly monodispersed polydispersity. Subsequent quaternization with CH 3 I and dimethyl sulfate converted the polymer into cationic macromonomers with diallylmethylammonium or allylmethylphenylammonium terminal groups, which are readily copolymerizable with other vinyl monomers such as acrylamide and vinylformamide.
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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 | 0.000 |
| 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 | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".