Block and Random Copolymers of 1,2-Cyclohexyl Cyclocarbonate and <scp>l</scp>-Lactide or Trimethylene Carbonate Synthesized by Ring-Opening Polymerization
Bibliographic record
Abstract
The sequential and random ring-opening polymerizations (ROP) of racemic - trans -cyclohexene carbonate ( rac -CHC) or enantiopure trans -( R, R )-cyclohexene carbonate (( R, R )-CHC) with l -lactide (LLA) or trimethylene carbonate (TMC) have been performed. Catalytic systems based on zinc diaminophenolate [(NNO)ZnEt] ((NNO) − = 2,4-di- tert -butyl-6-{[(2′-dimethylaminoethyl)methylamino]methyl}phenolate)) or tris[ N, N -bis(trimethysilyl)amide]yttrium (Y[N(SiMe 3 ) 2 ] 3 ) complexes, or a guanidine-type organocatalyst (1,5,7-triazabicyclo[4.4.0]dec-5-ene, TBD), combined to an alcohol (BnOH or i PrOH) as initiator/chain-transfer agent were used. Well-defined diblock P( rac -CHC)- b -PLLA and P(( R, R )-CHC)- b -PLLA and random P( rac -CHC)- co -PLLA and P( rac -CHC)- co -PTMC copolymers were thus synthesized with molar mass values up to M n,NMR = ca. 34 000 g mol –1 and rather narrow dispersity values ( Đ M = 1.2–1.7). 1 H and 13 C{ 1 H} NMR characterizations of the copolymers revealed the presence of −OBn or −O i Pr chain-end groups, thereby supporting the active role of exogenous alcohol as initiator. No decarboxylation reaction was ever observed during any copolymerization, thus providing PCHC/PLLA and PCHC/PTMC copolymers void of ether defects. Thermal analysis of the copolymers assessed by DSC and TGA confirmed their block or random structure. The block PCHC- b -PLA and the random PCHC- co -PLLA and PCHC- co -PTMC copolymers represent the first examples of such copolymers synthesized by ring-opening copolymerization of the two comonomers. The latter PCHC- co -PTMC copolymers randomly combining CHC and TMC units are the first examples ever reported.
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 | 0.000 |
| 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) | 0.002 | 0.001 |
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".