Bibliographic record
Abstract
Abstract This article describes the application of inverse gas chromatography (IGC) to the study of synthetic and natural polymers. The word “inverse” is used to indicate that the component of interest is the stationary phase, either as a finely divided powder or coating, dispersed on a suitable inert support and packed into a chromatographic column. The time required for a probe molecule to pass through the column gives a measure of the molecular interactions between the probe and the polymer which can be quantified with the help of chromatographic theory. Historically, most thermodynamic studies on polymers were carried out in dilute solution, but IGC provides information on condensed phases under conditions much more similar to those under which polymers are actually used. Using this technique, melting, glass and other solid‐phase transitions can be studied and quantified. Degrees of crystallinity can be determined in an unambiguous procedure without calibration by other methods. Solubility, permeability and diffusion constants can be determined for probe molecules. IGC is also used extensively in determining the permeability of additives such as antioxidants in polymers, as well as thermodynamic quantities such as activity coefficients, heats of solution, Flory–Huggins interaction parameters (χ), and solubility parameters. Surface areas can be measured at any desired temperature by the determination of the adsorption isotherms of suitable probes. Measurements on polymer blends can yield important information on polymer–polymer interactions and can be used to predict the compatibility of the components over a wide range of temperatures. The use of finite concentration IGC provides a rapid method of determining the density of crosslinks in rubber‐like polymers. Almost any commercial gas chromatograph can be easily modified to carry out IGC experiments by procedures described in this report. The method provides a wealth of information of both fundamental and practical importance in the study of polymeric materials.
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 | 0.003 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.003 | 0.003 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.003 | 0.004 |
| Insufficient payload (model declined to judge) | 0.003 | 0.004 |
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".