Shear-induced textural transitions in flow-aligning liquid crystal polymers
Bibliographic record
Abstract
The equations of nematodynamics are formulated, solved, and used to model textural transformations in sheared thermotropic flow-aligning nematic polymers. The solutions are classified and characterized using analytical, scaling, and numerical methods. It is found that as the shear rate increases, the pathway between an oriented nonplanar state and an oriented planar state is through texture formation and coarsening. The two shear-rate dependent dimensionless numbers that control the texture formation and coarsening process are Ericksen Er and Deborah De numbers. The emergence of texture is independent of the Deborah number, and occurs at $\mathrm{Er}{=10}^{4}.$ As the shear rate increases and $\mathrm{Er}>{10}^{4}$ the first texture that arises is a defect lattice. Further increases of the shear rate bring De close to 1, ignite the coarsening processes, and replace the defect lattice with a defect gas. The smallest texture length scale ${\mathcal{l}}_{t}$ occurs at the defect lattice-defect gas transition. In the defect lattice regime the texture length scale decreases with increasing shear rate as ${\mathcal{l}}_{t}\ensuremath{\propto}(\stackrel{\ifmmode \dot{}\else \.{}\fi{}}{\ensuremath{\gamma}}\ensuremath{-}{a)}^{\ensuremath{-}1/2},$ while in the defect gas regime it increases as ${\mathcal{l}}_{t}\ensuremath{\propto}(\stackrel{\ifmmode \dot{}\else \.{}\fi{}}{\ensuremath{\gamma}}\ensuremath{-}b\sqrt{(\stackrel{\ifmmode \dot{}\else \.{}\fi{}}{\ensuremath{\gamma}}\ensuremath{-}a)}\ensuremath{-}c{)}^{\ensuremath{-}1}.$ Finally when $\mathrm{De}>2,$ an oriented monodomain state emerges, and the texture vanishes since coarsening overpowers defect nucleation. It is found that the texture transition cascade $\mathrm{unoriented}\mathrm{}\mathrm{monodomain}\ensuremath{\Rightarrow}\mathrm{defect}\mathrm{}\mathrm{lattice}\ensuremath{\Rightarrow}\mathrm{defect}\mathrm{}\mathrm{gas}\ensuremath{\Rightarrow}\mathrm{oriented}\mathrm{}\mathrm{monodomain}$ is remarkably consistent with the experimentally observed textural transitions of sheared lyotropic nematic polymers.
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 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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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 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".