Orientation and Partial Disentanglement in Individual Electrospun Fibers: Diameter Dependence and Correlation with Mechanical Properties
Bibliographic record
Abstract
Electrospun fibers are versatile materials that exhibit unusual and tunable properties when studied at the single fiber level, including an exponential increase in modulus with a decreasing diameter toward the nanoscale. Understanding the detailed molecular organization giving rise to this behavior is a key for reaching the ultimate goal of controlling their properties and realizing their full potential as 1D materials. In particular, molecular orientation and chain disentanglement are thought to play a critical role, but their study in individual fibers has proven extremely challenging. Here, we quantify molecular orientation in more than 100 individual fibers of atactic polystyrene (PS) from the micro- to nanoscale by polarized Raman spectroscopy, and we probe for the first time a disentanglement-related conformation in the same spectra. We observe an exponential increase of both parameters when decreasing the fiber diameter below an impressively large onset of 2.5 μm, much larger than the typical onset values. The orientation quantified for 500 nm fibers is among the highest values ever reported for PS samples. A clear correlation is found with the previously published diameter dependence of modulus measured in individual PS fibers. Our results also highlight the longitudinal and radial structural heterogeneity of electrospun fibers and suggest separate mechanisms for molecular orientation and disentanglement, which is shown to be mainly situated in the fiber shell. Finally, we combine our observations in a model describing the evolution of chain organization with fiber diameter.
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) | 0.000 | 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".