Synthesis of triblock copolymers via metathetic degradation of poly-butadiene combined with ring-opening polymerization of D,l-lactide

Synthesis and characterization of natural rubber‐based telechelic oligomers via olefin metathesis

“…The increase in M n of the oligomers appeared to be more noticeable for higher CTA concentrations, which is different from what we expected. The GPC results disagree with the hypothesis that higher CTA concentration results in lower M n 12,28 ; this phenomenon is in accordance with the works done by Peruch's group 33 where metathesis degradation of trans ‐PI with ethylene was hindered by chain‐chain cross metathesis. Overall, 1‐hexene is an efficient CTA for NR degradation, and various controlled M n of NR oligomers can be obtained by controlling the mole ratio of NR/CTA.…”

“…chemistry and polymer synthesis. 11,12 Olefin metathesis is considered to conduct in the "quasicyclobutane" mechanism 13,14 involving the splitting and reforming of two carbon-carbon double bonds. It was discovered that the reactivity and selectivity of the catalyst play a significant role in the development of the olefin metathesis, resulting in various new commercial applications and methods for chemical synthesis.…”

“…Olefin metathesis is an effective method of designing and synthesizing special organic chemicals or polymers, especially oligomers with desirable functional groups, which has attracted increasing attentions in organic chemistry and polymer synthesis 11,12 . Olefin metathesis is considered to conduct in the “quasicyclobutane” mechanism 13,14 involving the splitting and reforming of two carbon–carbon double bonds.…”

“…Zou et al 29 reported the metathetic degradation of styrene‐butadiene rubber using allyl chloroacetate, allyl hexanoate, trifluoroethyl methacrylate, and 5‐hexenyl acetate as the CTAs in presence of Grubbs 2nd generation catalyst. Li et al 12 demonstrated the synthesis of ABA triblock copolymers via cross metathesis and ring opening polymerization from polybutadiene and d , l ‐lactide. As NR is a sustainable macromolecular resource, it would be meaningful if the resource can be used to produce high value functional materials.…”

Tandem ROMP/Hydrogenation Approach to Hydroxy-Telechelic Linear Polyethylene

“…As a result, the majority of ROMP-produced hydroxy-telechelic polyolefins, even those reported in recent years, have been synthesized using a protected CTA, typically cis -1,4-diacetoxy-2-butene, followed by an additional deprotection step (Scheme ). ,− Due to the increasing need for more sustainable chemical processes, the poor atom economy and additional waste of such a protection/deprotection strategy are undesirable. However, high yields with unprotected C4D have only been achieved in the specific case of the cyclic carbonate/olefin monomer 4,7-dihydro-1,3-dioxepin-2-one, which required long reaction times to reach full conversion …”