Modified lignin as a main composition for a new generation of polyurethanes
Bibliographic record
Abstract
This research aims at improving the integration of lignin in polyurethane (PU) rigid foams. First, lignin was chemically modified to introduce amine groups on its molecule. The purpose of this step is to enhance the lignin direct reactivity with isocyanate to form urea bonds and also to use this modified lignin as a catalyst for the main reaction involving polyol and isocyanate. A simple one-step approach, without toxic solvent, was used for this modification. The efficiency of this modification was verified using Fourier transform infrared spectroscopy (FTIR), electron dispersion X-ray (EDX) and scanning electron microscopy (SEM). Then, the resulting modified lignin was incorporated at 1 O and 20 wt % in the formulation of PU rigid foams. The influence of lignin on foaming ability was also evaluated , ln addition, the effect of modified lignin on mechanical properties, thermal conductivity and density of the foam was also investigated.
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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".