Synthesis of Poly(arylene ether ether ketone ketone) Copolymers Containing Pendant Sulfonic Acid Groups Bonded to Naphthalene as Proton Exchange Membrane Materials
Bibliographic record
Abstract
A new series of wholly aromatic poly(ether ether ketone ketone) containing pendant sulfonic acid groups (SPAEEKK) were conveniently prepared by potassium carbonate mediated nucleophilic polycondensation reactions of inexpensive commercially available monomers 1,3-bis(4-fluorobenzoyl)benzene (BFBB), sodium 6,7-dihydroxy-2-naphthalenesulfonate (DHNS), and 4,4‘-biphenol or hydroquinone in N -methyl- 2 -pyrrolidone (NMP) at 170 °C. FT-IR and NMR were used to characterize the structures and the sulfonate or sulfonic acid contents (SC) of the polymers. Flexible membrane films were obtained by casting N,N -dimethylacetamide (DMAc) solutions of copolymers. Membrane films in acid form were then obtained by treating the sodium form membrane films in 2 N sulfuric acid at room temperature. Glass-transition temperatures ( T g 's) and decomposition temperatures ( T d 's) of SPAEEKKs in both sodium and acid forms were determined. Water uptake and swelling ratio values increased with SCs and temperatures. The proton conductivities of acid form membrane films increased with SC value and temperature and reached 5.6 × 10 -2 S/cm at 100 °C for SPAEEKK-100.
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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) | 0.000 | 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 | 0.000 |
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".