We have previously reported thermally stable white-light luminescence from polymer hybrid films consisting of tetraphenylethene (TPE)-tethered polyhedral oligomeric silsesquioxane (POSS) and poly(1,4-phenylenevinylene) (PPV). We observed that the intensity ratios between the dual emission bands from the POSS and the conjugated polymer, and thus the color balance, were maintained even in the higher-temperature region. In this paper, the origin of the thermally stable dual-emission properties of these white-light-emitting hybrid films is investigated using a series of POSS derivatives with different tethered luminophores and various conjugated polymer matrices. We obtained homogeneous hybrid films and revealed that one of the key factors for the expression of dual-emission properties is the relationship between the photoluminescence quantum yields of the energy donors (fillers) (ΦD) and acceptors (polymers) (ΦA). When the emission quantum yield of either the donor or acceptor molecules is high, only an emission band originating from the molecule with the higher emission quantum yield can be observed. Dual emission from both the donor and acceptor is detectable only when the ΦD is as high as the ΦA or slightly higher than the ΦA. Based on these findings, we have demonstrated a logical design for dual-emissive materials. We also found that the affinity between POSS and polymers is responsible for maintaining the emission color balance at high temperatures. It was observed that POSS substituted with bulky groups can hybridize with conjugated polymer chains, and that the thermal behavior of the polymer is dominated by the POSS. As a result, the thermal stability can be enhanced. We revealed the origin of the thermally stable white-light luminesce properties of POSS hybrids based on two aspects.
{"title":"The origin of the thermally stable white-light emission property of POSS-conjugated polymer hybrid films","authors":"Satoru Saotome, Masayuki Gon, Kazuo Tanaka","doi":"10.1039/d5py00144g","DOIUrl":"https://doi.org/10.1039/d5py00144g","url":null,"abstract":"We have previously reported thermally stable white-light luminescence from polymer hybrid films consisting of tetraphenylethene (TPE)-tethered polyhedral oligomeric silsesquioxane (POSS) and poly(1,4-phenylenevinylene) (PPV). We observed that the intensity ratios between the dual emission bands from the POSS and the conjugated polymer, and thus the color balance, were maintained even in the higher-temperature region. In this paper, the origin of the thermally stable dual-emission properties of these white-light-emitting hybrid films is investigated using a series of POSS derivatives with different tethered luminophores and various conjugated polymer matrices. We obtained homogeneous hybrid films and revealed that one of the key factors for the expression of dual-emission properties is the relationship between the photoluminescence quantum yields of the energy donors (fillers) (<em>Φ</em><small><sub>D</sub></small>) and acceptors (polymers) (<em>Φ</em><small><sub>A</sub></small>). When the emission quantum yield of either the donor or acceptor molecules is high, only an emission band originating from the molecule with the higher emission quantum yield can be observed. Dual emission from both the donor and acceptor is detectable only when the <em>Φ</em><small><sub>D</sub></small> is as high as the <em>Φ</em><small><sub>A</sub></small> or slightly higher than the <em>Φ</em><small><sub>A</sub></small>. Based on these findings, we have demonstrated a logical design for dual-emissive materials. We also found that the affinity between POSS and polymers is responsible for maintaining the emission color balance at high temperatures. It was observed that POSS substituted with bulky groups can hybridize with conjugated polymer chains, and that the thermal behavior of the polymer is dominated by the POSS. As a result, the thermal stability can be enhanced. We revealed the origin of the thermally stable white-light luminesce properties of POSS hybrids based on two aspects.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"8 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vera Bocharova, Erin Drufva, John F. Cahill, Ivan Popov, Isaiah Dishner, Muchu Zhou, Gang Seob Jung, Andrew Ullman, Dana Carper, Joshua Damron, Jong Keum, Catalin Gainaru, Serena H. Chen, Jeffrey C. Foster, Joshua Michener
The enzymatic hydrolysis of polyamides offers a promising approach to reduce the environmental impact of chemical recycling by enabling lower reaction temperatures, eliminating toxic organic solvents, and enhancing product selectivity. Achieving this goal will require increasing the low overall yield of enzymatic hydrolysis. In this work, we studied the mechanism of hydrolysis of commercial Nylon-6,6 polymer with a thermostable Nylon hydrolyzing enzyme and identified the substrate characteristics that influence the efficiency and deconstruction product yield. These results will guide the development of effective substrate pre-treatment methods to improve the yield of valuable oligoamide building blocks via enzymatic hydrolysis.
{"title":"Factors Modulating the Hydrolysis of Nylon-6,6 by a Nylon Hydrolase Enzyme","authors":"Vera Bocharova, Erin Drufva, John F. Cahill, Ivan Popov, Isaiah Dishner, Muchu Zhou, Gang Seob Jung, Andrew Ullman, Dana Carper, Joshua Damron, Jong Keum, Catalin Gainaru, Serena H. Chen, Jeffrey C. Foster, Joshua Michener","doi":"10.1039/d5py00023h","DOIUrl":"https://doi.org/10.1039/d5py00023h","url":null,"abstract":"The enzymatic hydrolysis of polyamides offers a promising approach to reduce the environmental impact of chemical recycling by enabling lower reaction temperatures, eliminating toxic organic solvents, and enhancing product selectivity. Achieving this goal will require increasing the low overall yield of enzymatic hydrolysis. In this work, we studied the mechanism of hydrolysis of commercial Nylon-6,6 polymer with a thermostable Nylon hydrolyzing enzyme and identified the substrate characteristics that influence the efficiency and deconstruction product yield. These results will guide the development of effective substrate pre-treatment methods to improve the yield of valuable oligoamide building blocks via enzymatic hydrolysis.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"26 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Colloidal photonic crystals (CPCs) have attracted much attention due to their distinctive and vibrant structural colors. Precise control over the size and dispersity of nanoparticle is vital for high quality CPC patterns by bottom-up colloidal self-assembly. The polymerization-induced self-assembly (PISA) method has emerged as a promising strategy for preparing nanoparticles of specific morphology and size with good adaptability to a wide range of monomers and solvents. Nevertheless, achieving monodisperse particles in a specific particle size to fabricate structural color patterns by PISA remains a challenge. In this study, we present a novel aqueous PISA approach that enables the large-scale preparation of monodisperse nanospheres (diameter polydispersity < 1.001) and the fabrication of printable CPCs. The method allows for the large-scale preparation of uniform polymeric nanoparticles with precise size control, thus enabling accurate manipulation of structural colors. The aqueous dispersions were used as inks to print structural color patterns on paper substrates, achieving photonic patterns with characteristic angle-dependent and water-responsive color variations. This study highlights the significant potential of the PISA method for advancing the fabrication of functional colloidal materials and expanding the application of CPCs.
{"title":"Monodisperse and size-regulable nanoparticles by polymerization-induced self-assembly for printable colloidal photonic crystals","authors":"Nankai An, Xushuai Chen, Xi Chen, Jinying Yuan","doi":"10.1039/d5py00077g","DOIUrl":"https://doi.org/10.1039/d5py00077g","url":null,"abstract":"Colloidal photonic crystals (CPCs) have attracted much attention due to their distinctive and vibrant structural colors. Precise control over the size and dispersity of nanoparticle is vital for high quality CPC patterns by bottom-up colloidal self-assembly. The polymerization-induced self-assembly (PISA) method has emerged as a promising strategy for preparing nanoparticles of specific morphology and size with good adaptability to a wide range of monomers and solvents. Nevertheless, achieving monodisperse particles in a specific particle size to fabricate structural color patterns by PISA remains a challenge. In this study, we present a novel aqueous PISA approach that enables the large-scale preparation of monodisperse nanospheres (diameter polydispersity < 1.001) and the fabrication of printable CPCs. The method allows for the large-scale preparation of uniform polymeric nanoparticles with precise size control, thus enabling accurate manipulation of structural colors. The aqueous dispersions were used as inks to print structural color patterns on paper substrates, achieving photonic patterns with characteristic angle-dependent and water-responsive color variations. This study highlights the significant potential of the PISA method for advancing the fabrication of functional colloidal materials and expanding the application of CPCs.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"183 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lili Zhao, Suzhen Wang, Zhezhe Li, Jian Gu, Hailong Che
pH-responsive polymer vesicles (polymersomes) hold great potential in the field of drug delivery. However, the use of pH-responsive polymersome systems as drug vehicles generally suffers from low cellular uptake efficiency. In this work, we constructed guanidinylated pH-responsive polymersomes comprising poly(trimethylene carbonate) (PTMC) based polymers with pedants of pH-responsive moieties. The polymersomes are characterized by the pH-induced disassembly, which was utilized for controlled drug release. We find that coupling of guanidine groups with the surface of polymersomes can significantly improve the internalization of polymersomes within cancer cells due to the strong interactions between guanidines and cell surface membranes. Additionally, the in vitro studies demonstrate that drug-loaded guanidine-functionalized polymersomes are capable of inducing enhanced cancer cell death as compared to unfunctionalized polymersomes. Hence, the synergistic combination of pH-responsive property and cell-penetrating feature in polymersome particles offers a new strategy for constructing advanced pH-responsive polymeric nanocarriers.
{"title":"Constructing pH-responsive poly(trimethylene carbonate) (PTMC)-based polymersomes functionalized with cell-penetrating guanidines","authors":"Lili Zhao, Suzhen Wang, Zhezhe Li, Jian Gu, Hailong Che","doi":"10.1039/d4py01464b","DOIUrl":"https://doi.org/10.1039/d4py01464b","url":null,"abstract":"pH-responsive polymer vesicles (polymersomes) hold great potential in the field of drug delivery. However, the use of pH-responsive polymersome systems as drug vehicles generally suffers from low cellular uptake efficiency. In this work, we constructed guanidinylated pH-responsive polymersomes comprising poly(trimethylene carbonate) (PTMC) based polymers with pedants of pH-responsive moieties. The polymersomes are characterized by the pH-induced disassembly, which was utilized for controlled drug release. We find that coupling of guanidine groups with the surface of polymersomes can significantly improve the internalization of polymersomes within cancer cells due to the strong interactions between guanidines and cell surface membranes. Additionally, the in vitro studies demonstrate that drug-loaded guanidine-functionalized polymersomes are capable of inducing enhanced cancer cell death as compared to unfunctionalized polymersomes. Hence, the synergistic combination of pH-responsive property and cell-penetrating feature in polymersome particles offers a new strategy for constructing advanced pH-responsive polymeric nanocarriers.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"70 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143666399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuhang Zeng, Die Huang, Baixue Li, Jia Wang, Rong Hu
Polymeric materials featuring aggregation-induced emission (AIE) have been developed as emerging luminescent materials benefiting from the superiorities of facial modification, synergetic effect, smart responsiveness, and outstanding photophysical properties. Incorporating AIE luminogens into polymer fabrication gives the obtained polymeric materials fascinating properties, providing a feasible and effective approach for biosensor construction with fast response, high sensitivity, and excellent stability. In this review, the advancement of AIE polymers for biosensing applications in the recent five years are summarized, and the applications in ion detections of the physiological environment, bio-related molecules detection, bioimaging, and intracellular temperature monitoring will be discussed in detail. Finally, the current challenges and perspectives of these promising materials on future development have been discussed at the end of this review.
{"title":"AIE Polymers for Biosensing Applications","authors":"Yuhang Zeng, Die Huang, Baixue Li, Jia Wang, Rong Hu","doi":"10.1039/d5py00051c","DOIUrl":"https://doi.org/10.1039/d5py00051c","url":null,"abstract":"Polymeric materials featuring aggregation-induced emission (AIE) have been developed as emerging luminescent materials benefiting from the superiorities of facial modification, synergetic effect, smart responsiveness, and outstanding photophysical properties. Incorporating AIE luminogens into polymer fabrication gives the obtained polymeric materials fascinating properties, providing a feasible and effective approach for biosensor construction with fast response, high sensitivity, and excellent stability. In this review, the advancement of AIE polymers for biosensing applications in the recent five years are summarized, and the applications in ion detections of the physiological environment, bio-related molecules detection, bioimaging, and intracellular temperature monitoring will be discussed in detail. Finally, the current challenges and perspectives of these promising materials on future development have been discussed at the end of this review.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"183 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recovered carbon black (rCB), a regenerative product from the thermal pyrolysis of waste tires, can be reused as a reinforcement for rubbers, with the goal of achieving high-value utilization of resources and promoting sustainable development. However, the inert surface of rCB causes poor compatibility with rubbers and results in low reinforcement efficiency. In this work, we synthesized acylhydrazine-functionalized polysulfide (SPT) and utilized it as an interfacial modifier for demineralized rCB (drCB)-filled natural rubber (NR) composites. SPT was synthesized through a one-pot sequential copolymerization of sulfur, styrene and thioctic acylhydrazine. The acylhydrazine moieties of SPT have multiple interactions with the oxygen-containing groups on drCB surface, while the polysulfide segments are able to graft onto NR chains, thereby creating molecular bridge between drCB and NR. Morphological and interfacial studies show that drCB dispersion is remarkably improved and interfacial adhesion is greatly enhanced upon the addition of SPT. As a consequence, the reinforcement efficiency of drCB is improved and the hysteresis loss of resulted composites is significantly decreased.
{"title":"Reviving recovered carbon black as reinforcement for natural rubber by utilizing acylhydrazine-functionalized polysulfide as an intelligent interfacial modifier","authors":"Senmao Yu, Zhenghai Tang, Dong Wang, Siwu Wu, Fei Chen, Baochun Guo, Liqun Zhang","doi":"10.1039/d5py00111k","DOIUrl":"https://doi.org/10.1039/d5py00111k","url":null,"abstract":"Recovered carbon black (rCB), a regenerative product from the thermal pyrolysis of waste tires, can be reused as a reinforcement for rubbers, with the goal of achieving high-value utilization of resources and promoting sustainable development. However, the inert surface of rCB causes poor compatibility with rubbers and results in low reinforcement efficiency. In this work, we synthesized acylhydrazine-functionalized polysulfide (SPT) and utilized it as an interfacial modifier for demineralized rCB (drCB)-filled natural rubber (NR) composites. SPT was synthesized through a one-pot sequential copolymerization of sulfur, styrene and thioctic acylhydrazine. The acylhydrazine moieties of SPT have multiple interactions with the oxygen-containing groups on drCB surface, while the polysulfide segments are able to graft onto NR chains, thereby creating molecular bridge between drCB and NR. Morphological and interfacial studies show that drCB dispersion is remarkably improved and interfacial adhesion is greatly enhanced upon the addition of SPT. As a consequence, the reinforcement efficiency of drCB is improved and the hysteresis loss of resulted composites is significantly decreased.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"56 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oliver Clarke, Abdulrahman Bashir, Sophie Wazlowski, Sara Ptaszynska, Brian H. Northrop, Benjamin Elling
Sulphur-containing polymers are utilized in applications ranging from vulcanized rubbers to optical materials and proton conducting membranes. Typically, sulphur-containing polymers are synthesized via condensation methods. While ring-openining metathesis polymerization is a useful tool for polymerizing functional monomers, previous reports have shown difficulties incorporating sulphur-containing functional groups due to Ru-S interactions. In this work, we report the synthesis and polymerization of a number of poly(oxa)norobornenes containing sulfonate, sulfone, and sulfoxide sidechains. We demonstrate the effects of the identity of the bridge group, sidechain R groups, and substituent stereochemistry on polymerization rates, molecular weight distrubitons, and thermal properties. Interestingly, while the exo-norbornene phenyl sulfoxide monomer was effectively polymerized, the endo isomer resulted in exclusive single addition to the Ru catalyst due to sulphur chelation to the metal centre. This monomer could however be used for alternating copolymerization with other cyclic olefins.
{"title":"Ring-Opening Metathesis Polymerization of (Oxa)Norbornenes with Sulfonate, Sulfone, and Sulfoxide Sidechains","authors":"Oliver Clarke, Abdulrahman Bashir, Sophie Wazlowski, Sara Ptaszynska, Brian H. Northrop, Benjamin Elling","doi":"10.1039/d4py01307g","DOIUrl":"https://doi.org/10.1039/d4py01307g","url":null,"abstract":"Sulphur-containing polymers are utilized in applications ranging from vulcanized rubbers to optical materials and proton conducting membranes. Typically, sulphur-containing polymers are synthesized via condensation methods. While ring-openining metathesis polymerization is a useful tool for polymerizing functional monomers, previous reports have shown difficulties incorporating sulphur-containing functional groups due to Ru-S interactions. In this work, we report the synthesis and polymerization of a number of poly(oxa)norobornenes containing sulfonate, sulfone, and sulfoxide sidechains. We demonstrate the effects of the identity of the bridge group, sidechain R groups, and substituent stereochemistry on polymerization rates, molecular weight distrubitons, and thermal properties. Interestingly, while the exo-norbornene phenyl sulfoxide monomer was effectively polymerized, the endo isomer resulted in exclusive single addition to the Ru catalyst due to sulphur chelation to the metal centre. This monomer could however be used for alternating copolymerization with other cyclic olefins.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"20 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To improve mechanical properties of a hydrogel, the construction of uniform network structures and/or the incorporation of energy-dissipating structures are important. In this study, we focused on gel synthesis using multiarm star polymers with a microgel core, which is expected to establish the abovementioned structures in vinyl polymer hydrogels. A series of star poly(N-isopropylacrylamide)s (PNIPAAms) with different arm molecular weights and vinyl group contents in the core were synthesized via an arm-first method using reversible addition-fragmentation chain transfer (RAFT) polymerization. The obtained star polymers were employed as crosslinkers to prepare polyacrylamide (PAAm) hydrogel by free radical polymerization. The content of vinyl groups in the core was critical for producing a hydrogel, and significantly affected the mechanical properties of the product gels, which is indicative of the high effectiveness of the star polymer core as a crosslinker. The molecular weight of the arm chains of the star polymers also played a pivotal role in controlling the mechanical properties of the product gels: moderately long arm chains, which form hydrogen bonding, were shown to act as energy-dissipating units. An equally important feature is the nearly even dispersion of the star crosslinkers in the network structure, as confirmed by SAXS, which achieved an increase in toughness without impairing the elongation upon increasing the main chain monomer concentration in the gelation reaction.
{"title":"Structure-Property Correlation of Hydrogels Obtained via Radical Polymerization Using Central Cores of Multiarm Star Polymers as Crosslinkers","authors":"Shohei Ida, Souma Suzuki, Shogo Toda, Hiroki Takeshita, Masatoshi Oyama, Keiji Nakajima, Shokyoku Kanaoka","doi":"10.1039/d5py00014a","DOIUrl":"https://doi.org/10.1039/d5py00014a","url":null,"abstract":"To improve mechanical properties of a hydrogel, the construction of uniform network structures and/or the incorporation of energy-dissipating structures are important. In this study, we focused on gel synthesis using multiarm star polymers with a microgel core, which is expected to establish the abovementioned structures in vinyl polymer hydrogels. A series of star poly(N-isopropylacrylamide)s (PNIPAAms) with different arm molecular weights and vinyl group contents in the core were synthesized via an arm-first method using reversible addition-fragmentation chain transfer (RAFT) polymerization. The obtained star polymers were employed as crosslinkers to prepare polyacrylamide (PAAm) hydrogel by free radical polymerization. The content of vinyl groups in the core was critical for producing a hydrogel, and significantly affected the mechanical properties of the product gels, which is indicative of the high effectiveness of the star polymer core as a crosslinker. The molecular weight of the arm chains of the star polymers also played a pivotal role in controlling the mechanical properties of the product gels: moderately long arm chains, which form hydrogen bonding, were shown to act as energy-dissipating units. An equally important feature is the nearly even dispersion of the star crosslinkers in the network structure, as confirmed by SAXS, which achieved an increase in toughness without impairing the elongation upon increasing the main chain monomer concentration in the gelation reaction.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"35 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Francesco Felician, M. N. Antonopoulou, Nghia P. Truong, Asja A. Kroeger, Michelle Coote, Glen R. Jones, Athina Anastasaki
Reversible addition−fragmentation chain-transfer (RAFT) depolymerization represents an attractive and low-temperature chemical recycling methodology enabling the near-quantitative regeneration of pristine monomer. Yet, several mechanistic aspects of the process remain elusive. Herein, we shine a light on the RAFT depolymerization mechanism by elucidating the effect of pendant side chains on the depolymerization kinetics. A systematic increase of the number of carbons on the side chain, or the number of ethylene glycol units, revealed a significant rate acceleration. Notably, radical initiator addition during the depolymerization of poly(methyl methacrylate) and poly(hexyl methacrylate) resulted in rate equilibration, indicating that chain activation is the rate-determining step in RAFT depolymerization. Moreover, incorporation of a low DP of hexyl monomer as the second block of poly(methyl methacrylate) led to comparable rates with poly(hexyl methacrylate) homopolymer, confirming the rate determining step. Computational investigations further corroborate this finding, revealing that chain-end fragmentation is energetically more favorable in longer-side-chain methacrylates, which accounts for the experimentally observed rate acceleration. These insights not only deepen our understanding of depolymerization but also pave the way for developing more efficient and customizable depolymerization systems.
{"title":"Unravelling the Effect of Side Chain on RAFT Depolymerization; Identifying the Rate Determining Step","authors":"Francesco Felician, M. N. Antonopoulou, Nghia P. Truong, Asja A. Kroeger, Michelle Coote, Glen R. Jones, Athina Anastasaki","doi":"10.1039/d5py00212e","DOIUrl":"https://doi.org/10.1039/d5py00212e","url":null,"abstract":"Reversible addition−fragmentation chain-transfer (RAFT) depolymerization represents an attractive and low-temperature chemical recycling methodology enabling the near-quantitative regeneration of pristine monomer. Yet, several mechanistic aspects of the process remain elusive. Herein, we shine a light on the RAFT depolymerization mechanism by elucidating the effect of pendant side chains on the depolymerization kinetics. A systematic increase of the number of carbons on the side chain, or the number of ethylene glycol units, revealed a significant rate acceleration. Notably, radical initiator addition during the depolymerization of poly(methyl methacrylate) and poly(hexyl methacrylate) resulted in rate equilibration, indicating that chain activation is the rate-determining step in RAFT depolymerization. Moreover, incorporation of a low DP of hexyl monomer as the second block of poly(methyl methacrylate) led to comparable rates with poly(hexyl methacrylate) homopolymer, confirming the rate determining step. Computational investigations further corroborate this finding, revealing that chain-end fragmentation is energetically more favorable in longer-side-chain methacrylates, which accounts for the experimentally observed rate acceleration. These insights not only deepen our understanding of depolymerization but also pave the way for developing more efficient and customizable depolymerization systems.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"34 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Inspired by the highly efficient and enantioselective reactions catalyzed by biomacromolecules, developing artificial helical polymer-supported catalysts is an attractive and meaningful field. In this work, a series of helical polymers poly-1ns with controlled molecular mass (Mns) and narrow molecular mass distribution (Mw/Mns) bearing cinchona alkaloid pendants was obtained by asymmetric polymerization of corresponding monomer. The poly-1ns exhibited intense positive Cotton effect at 364 nm, indicating preferred righted-handed helix was formed in their backbone. Due to the catalytic groups on pendants and helix in the backbone, poly-1ns exhibited satisfied catalytic efficiency on asymmetric Henry reaction. Compared to small molecule (1) with similar structures, enantioselectivity of Henry reaction was significantly enhanced using poly-1n as catalyst. The enantiomeric excess (ee) value of the Henry reaction could be up to 75%. Furthermore, the helical polyisocyanide catalyst could be recovered and reused facilely at least five cycles without apparent significant loss of its enantioselectivity.
{"title":"Optically active helical polymers bearing cinchona alkaloid pendants: an efficient chiral organocatalyst for asymmetric Henry reaction","authors":"Xing-Yu Zhou, Wen-Gang Huang, Xue-Cheng Sun, Hui Zou, Li Zhou, Zong-Quan Wu","doi":"10.1039/d4py01284d","DOIUrl":"https://doi.org/10.1039/d4py01284d","url":null,"abstract":"Inspired by the highly efficient and enantioselective reactions catalyzed by biomacromolecules, developing artificial helical polymer-supported catalysts is an attractive and meaningful field. In this work, a series of helical polymers poly-1ns with controlled molecular mass (Mns) and narrow molecular mass distribution (Mw/Mns) bearing cinchona alkaloid pendants was obtained by asymmetric polymerization of corresponding monomer. The poly-1ns exhibited intense positive Cotton effect at 364 nm, indicating preferred righted-handed helix was formed in their backbone. Due to the catalytic groups on pendants and helix in the backbone, poly-1ns exhibited satisfied catalytic efficiency on asymmetric Henry reaction. Compared to small molecule (1) with similar structures, enantioselectivity of Henry reaction was significantly enhanced using poly-1n as catalyst. The enantiomeric excess (ee) value of the Henry reaction could be up to 75%. Furthermore, the helical polyisocyanide catalyst could be recovered and reused facilely at least five cycles without apparent significant loss of its enantioselectivity.","PeriodicalId":100,"journal":{"name":"Polymer Chemistry","volume":"25 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143654035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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