Bibliographic record
Abstract
A method for the preparation of arborescent polystyrenes based on acetyl coupling sites is described. The acetyl functionalities are randomly introduced on the grafting substrate by reacting polystyrene with acetyl chloride in the presence of anhydrous AlCl 3 in nitrobenzene. Anionic polymerization of styrene with sec -butyllithium yields polystyryllithium serving as side chains; coupling of the side chains with the acetylated substrate generates the graft polymers. Direct coupling of polystyryllithium with acetylated polystyrene suffers from a low grafting yield (∼65% for a linear substrate), due to deactivation of the macroanions by side reactions. End-capping of polystyryllithium with a few isoprene or 2-vinylpyridine units, along with the addition of LiCl, increases the grafting yield to >95%. Repetition of acetylation and anionic grafting cycles leads to generations of arborescent polymers with a low polydispersity index ( M w / M n = 1.07−1.09). The polymers are characterized by a very compact structure and by a branching functionality and molecular weight increasing geometrically for successive generations. Tailor-designed arborescent architectures are attainable by this “graft-on-graft” procedure, by controlling the acetylation level and the molecular weight of the side chains used for each grafting reaction.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 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 | 0.000 |
| 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 teacher head, 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".