Solid-State NMR and Small-Angle X-ray Scattering Study of Microphase Structure of Amorphous and Semicrystalline Poly(styrene−ethylene oxide) Diblock Copolymers
Bibliographic record
Abstract
The microphase structure of a series of poly(styrene−ethylene oxide) (SEO) block copolymers has been studied by solid-state NMR and small-angle X-ray scattering (SAXS) techniques. The differential scanning calorimetry studies indicate that the majority of SEO samples are semicrystalline. For the completely amorphous SEO, solid-state NMR 1 H spin diffusion was used to determine the sizes of various domains, interfacial thickness, and interdomain distances by the initial-rate approximation and by numerical simulation with a pure spin diffusion model. The results obtained from the above two methods, the initial-rate approximation and the numerical simulation, are generally in good agreement, but the interdomain distance estimated from NMR is relatively lower than that obtained from SAXS. The discrepancy is probably caused by the simulation model used in the NMR data interpretation. For the semicrystalline SEO samples, the relative locations of multiple Bragg peaks and the location of the first-order maximum in the SAXS data were used to determine the morphology and the size of the interdomain distance of the material. This is a typical example where either NMR or SAXS alone cannot yield complete phase structure information for both amorphous and semicrystalline SEO materials. A combination of the above two techniques is necessary and allows us to explore the phase structure of both the amorphous and the semicrystalline SEO samples and also examine the validity of the pure spin diffusion model used for the NMR analysis.
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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) | 0.000 | 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 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".