Facile Synthesis of C<i><sub>x</sub></i>(AB)<i><sub>y</sub></i>C<i><sub>x</sub></i> Triblock Silicone Copolymers Utilizing Moisture Mediated Living‐End Chain Extension
Bibliographic record
Abstract
Abstract The physical and chemical properties of silicone block copolymers depend upon the block size and chemical characteristics. Silicone block copolymer synthetic procedures typically involve chain‐growth polymerization techniques that are difficult to control, require low temperatures, inert atmospheres, etc., and which are subject to polymer chain redistribution; the latter process broadens dispersity and leads to the formation of cyclic monomers that must be removed. Once formed, tuning the size of the individual blocks is challenging. The controlled one‐pot synthesis of organosilicone Cx (AB)y Cx triblock copolymers with aryl rich cores is demonstrated by exploiting the Piers–Rubinsztajn reaction and a hydrolysis/condensation polymerization, both using B(C6F5)3 catalysis. A fast Piers–Rubinsztajn reaction between HSi‐terminated silicones and aryl phenyl ethers leads preferentially to the formation of the aryl‐rich core. Subsequent addition of HSi‐terminated silicones permits controlled chain extension of the flanking homosilicone blocks via a slower hydrolysis/condensation facilitated by atmospheric moisture and leads in one pot, two steps to clean Cx (AB)y Cx triblocks. The products are surprisingly resilient to hydrolysis.
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".