Thermal degradation of impact‐modified <scp>PMMA</scp> in mechanical and chemical recycling
Bibliographic record
Abstract
Abstract Poly (methyl methacrylate) (PMMA) is a thermoplastic with outstanding tensile strength, UV resistance, and a high level of transparency that has been used widely for optical applications such as glazing in the automobile industry. Mechanical recycling, the most widespread method, degrades the physical properties and prevents reusing PMMA in transparent applications. Thermal depolymerization to recover methyl methacrylate (MMA) monomer is becoming an alternative route for PMMA recycling. In this paper, the thermal depolymerization process of impact‐modified PMMA in a micro fluidized bed reactor was investigated. The pyrolysis was conducted over aluminium oxide () and fluid‐cracking catalyst (FCC) as catalytic beds; sand and SiC as inert beds at temperatures below . A mechanical recycling process was also simulated using sequential injection moulding to investigate its impact on the properties of PMMA. After 5 cycles of injection moulding, the impact strength and optical properties of PMMA were severely diminished due to an increase in free volume and partial thermal degradation. Regarding PMMA pyrolysis, demonstrated limited cracking ability with a maximum MMA yield of 46%, as opposed to FCC, which over‐cracked both PMMA and MMA into coke and unwanted products. In contrast, non‐catalytic beds exhibited higher activity for MMA recovery, with SiC yielding the highest amount of 92% at .
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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 | 0.001 |
| 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) | 0.000 | 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".