Utilizing the unique properties of fluorine substitution is an effective strategy for constructing highly functional materials. Here, we synthesized a novel copolymer composed of [1.1.1]propellane and perfluoro(propyl vinyl ether) (PPVE), rich in alternating sequences. The spin-coated copolymer film was amorphous, and its surface exhibited an extremely low surface free energy (γ). The γ value was lower than that of polytetrafluoroethylene despite containing only 40 mol % PPVE units. This can be attributed to the cancellation of the C-F dipole moments by the entirely random orientation of the fluorine units.
{"title":"Highly Alternating Copolymer of [1.1.1]Propellane and Perfluoro Vinyl Ether: Forming a Hydrophobic and Oleophobic Surface with <50% Fluorine Monomer Content.","authors":"Mizuki Okuda, Midori Akiyama, Kosuke Funahashi, Junki Masuda, Ai Kohata, Shintaro Nakagawa, Kimiaki Kashiwagi, Norihide Sugiyama, Takashi Okazoe, Daisuke Kawaguchi","doi":"10.1021/acsmacrolett.4c00558","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00558","url":null,"abstract":"<p><p>Utilizing the unique properties of fluorine substitution is an effective strategy for constructing highly functional materials. Here, we synthesized a novel copolymer composed of [1.1.1]propellane and perfluoro(propyl vinyl ether) (PPVE), rich in alternating sequences. The spin-coated copolymer film was amorphous, and its surface exhibited an extremely low surface free energy (γ). The γ value was lower than that of polytetrafluoroethylene despite containing only 40 mol % PPVE units. This can be attributed to the cancellation of the C-F dipole moments by the entirely random orientation of the fluorine units.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142398650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-10DOI: 10.1021/acsmacrolett.4c00505
Ronard Herrera Monegro, Ramanan Krishnamoorti, Megan L. Robertson
Developing effective recycling pathways for polyolefin waste, enabling a move to a circular economy, is an imperative that must be met. Postuse modification has shown promising results in upcycling polyolefins, removing the limitation of inertness, and improving the final physical properties of the recycled material while extending its useful lifetime. Grafting of maleic anhydride groups to polypropylene is an established industrial process that enhances its reactivity and provides a convenient route to further functionalization and upcycling. In this work, maleic anhydride grafted polypropylene was hydroxylated and subsequently cured with a diisocyanate to form a thermoset polyurethane (PU). The crystal structure (unit cell and lamellar structure) of the polypropylene (PP) was preserved in the PU. At room temperature, the PU showed a high modulus due to the crystallization behavior of the PP; upon increasing the temperature above the melting temperature, the modulus decreased to a rubbery plateau, consistent with formation of a network. The resulting PU showed a higher glass transition temperature and lower degree of crystallinity than its PP predecessor due to the crosslinked nature of the polymer. The mechanical integrity of the PU was maintained through several reprocessing cycles due to the melt processability enabled by the presence of a urethane exchange catalyst. This functionalization and upcycling route thus offers a promising alternative to repurposing PP waste in which the creation of melt-processable thermoset polymers expands applications for the materials.
{"title":"Functionalization and Repurposing of Polypropylene to a Thermoset Polyurethane","authors":"Ronard Herrera Monegro, Ramanan Krishnamoorti, Megan L. Robertson","doi":"10.1021/acsmacrolett.4c00505","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00505","url":null,"abstract":"Developing effective recycling pathways for polyolefin waste, enabling a move to a circular economy, is an imperative that must be met. Postuse modification has shown promising results in upcycling polyolefins, removing the limitation of inertness, and improving the final physical properties of the recycled material while extending its useful lifetime. Grafting of maleic anhydride groups to polypropylene is an established industrial process that enhances its reactivity and provides a convenient route to further functionalization and upcycling. In this work, maleic anhydride grafted polypropylene was hydroxylated and subsequently cured with a diisocyanate to form a thermoset polyurethane (PU). The crystal structure (unit cell and lamellar structure) of the polypropylene (PP) was preserved in the PU. At room temperature, the PU showed a high modulus due to the crystallization behavior of the PP; upon increasing the temperature above the melting temperature, the modulus decreased to a rubbery plateau, consistent with formation of a network. The resulting PU showed a higher glass transition temperature and lower degree of crystallinity than its PP predecessor due to the crosslinked nature of the polymer. The mechanical integrity of the PU was maintained through several reprocessing cycles due to the melt processability enabled by the presence of a urethane exchange catalyst. This functionalization and upcycling route thus offers a promising alternative to repurposing PP waste in which the creation of melt-processable thermoset polymers expands applications for the materials.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142397810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-09DOI: 10.1021/acsmacrolett.4c00618
Hyo Won Lee, Jeung Gon Kim
Herein, we present a highly efficient method for synthesizing multifunctional polymers. This method involves the sequential postpolymerization modification (PPM) of a highly reactive aldehyde polymer. We introduce an allylic alcohol functionality into the polymer backbone via Barbier-type allylation, a process facilitated by easy-to-handle indium(0) powder. This step enables the formation of orthogonal pendants, secondary alcohol, and terminal alkene, which can be further functionalized through esterification and thiol–ene click reactions. All of these processes are carried out under mild conditions, ensuring high efficiency and a wide range of functional groups. Our study underscores PPM’s operational simplicity and versatility in developing advanced polymer materials and expanding the scope of multifunctional polymer design.
{"title":"Multifunctional Polymer Synthesis via Sequential Postpolymerization Modification Using a Single Aldehyde Repeat Unit: Allylation and Orthogonal Esterification and Thiol–ene Reaction","authors":"Hyo Won Lee, Jeung Gon Kim","doi":"10.1021/acsmacrolett.4c00618","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00618","url":null,"abstract":"Herein, we present a highly efficient method for synthesizing multifunctional polymers. This method involves the sequential postpolymerization modification (PPM) of a highly reactive aldehyde polymer. We introduce an allylic alcohol functionality into the polymer backbone via Barbier-type allylation, a process facilitated by easy-to-handle indium(0) powder. This step enables the formation of orthogonal pendants, secondary alcohol, and terminal alkene, which can be further functionalized through esterification and thiol–ene click reactions. All of these processes are carried out under mild conditions, ensuring high efficiency and a wide range of functional groups. Our study underscores PPM’s operational simplicity and versatility in developing advanced polymer materials and expanding the scope of multifunctional polymer design.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142385181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-09DOI: 10.1021/acsmacrolett.4c00443
Jiye Zhao, Dongdong Wang, Xi Zhang, Yaodong Di, Shuai Yang, Lesan Yan
Polymeric nanocarriers have attracted significant attention in the field of anticancer drug delivery due to their unique advantages. However, designing nanocarriers that can maintain stability in the bloodstream while achieving specific drug release within tumor cells remains a major challenge. To address this issue, constructing reversible cross-linked polymeric nanocarriers that are sensitive to the intracellular reducible glutathione (GSH) characteristic of the tumor microenvironment is a promising strategy. Based on this, we designed and synthesized two novel six-membered bicyclic carbonate monomers containing disulfide (DSBC) and trisulfide (TSBC) bonds. Through a one-step ring-opening polymerization, a series of reduction-sensitive polycarbonate copolymers (i.e., PEG–PDSBC and PEG–PTSBC) were prepared, and doxorubicin (DOX)-loaded nanoparticles were fabricated using a nanoprecipitation method. The in vitro drug release behaviors of these nanoparticles were systematically investigated. The results showed that these polymers, due to the cross-linked structure formed by the ring-opening polymerization of their bicyclic monomers, could self-assemble into stable nanoparticles. Under different concentrations of glutathione, DOX-loaded PEG–PTSBC nanoparticles demonstrated faster drug release, indicating more optimized intracellular drug release properties. Further cytotoxicity experiments revealed that both types of blank nanoparticles exhibited good biocompatibility with the 4T1 and NIH-3T3 cells. Fluorescence microscopy and flow cytometry results further indicated that DOX-loaded PEG–PTSBC nanoparticles released more drugs in 4T1 cells, significantly inhibiting tumor cell growth compared with DOX-loaded PEG–PDSBC nanoparticles, with no noticeable difference in NIH-3T3 normal cells. In conclusion, this study suggests that trisulfide cross-linked polycarbonate-based nanocarriers hold promise as an anticancer drug delivery system that combines stability in the bloodstream with specific intracellular drug release, offering new insights for the development of novel, efficient, and safe anticancer nanomedicines.
{"title":"Preparation of Disulfide/Trisulfide Core-Cross-Linked Polycarbonate Nanocarriers for Intracellular Reduction-Triggered Drug Release","authors":"Jiye Zhao, Dongdong Wang, Xi Zhang, Yaodong Di, Shuai Yang, Lesan Yan","doi":"10.1021/acsmacrolett.4c00443","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00443","url":null,"abstract":"Polymeric nanocarriers have attracted significant attention in the field of anticancer drug delivery due to their unique advantages. However, designing nanocarriers that can maintain stability in the bloodstream while achieving specific drug release within tumor cells remains a major challenge. To address this issue, constructing reversible cross-linked polymeric nanocarriers that are sensitive to the intracellular reducible glutathione (GSH) characteristic of the tumor microenvironment is a promising strategy. Based on this, we designed and synthesized two novel six-membered bicyclic carbonate monomers containing disulfide (DSBC) and trisulfide (TSBC) bonds. Through a one-step ring-opening polymerization, a series of reduction-sensitive polycarbonate copolymers (i.e., PEG–PDSBC and PEG–PTSBC) were prepared, and doxorubicin (DOX)-loaded nanoparticles were fabricated using a nanoprecipitation method. The <i>in vitro</i> drug release behaviors of these nanoparticles were systematically investigated. The results showed that these polymers, due to the cross-linked structure formed by the ring-opening polymerization of their bicyclic monomers, could self-assemble into stable nanoparticles. Under different concentrations of glutathione, DOX-loaded PEG–PTSBC nanoparticles demonstrated faster drug release, indicating more optimized intracellular drug release properties. Further cytotoxicity experiments revealed that both types of blank nanoparticles exhibited good biocompatibility with the 4T1 and NIH-3T3 cells. Fluorescence microscopy and flow cytometry results further indicated that DOX-loaded PEG–PTSBC nanoparticles released more drugs in 4T1 cells, significantly inhibiting tumor cell growth compared with DOX-loaded PEG–PDSBC nanoparticles, with no noticeable difference in NIH-3T3 normal cells. In conclusion, this study suggests that trisulfide cross-linked polycarbonate-based nanocarriers hold promise as an anticancer drug delivery system that combines stability in the bloodstream with specific intracellular drug release, offering new insights for the development of novel, efficient, and safe anticancer nanomedicines.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142385932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-09DOI: 10.1021/acsmacrolett.4c00570
Thomas Habets, Raphaël Méreau, Fabiana Siragusa, Bruno Grignard, Christophe Detrembleur
Herein, the long-standing challenge of the ring-opening aminolysis of CO2-derived tetrasubstituted cyclic carbonates at room temperature (r.T) is overcome under catalyst-free conditions. Molecular design of the cyclic carbonate by substitution of an alkyl group by a thioether unlocks quantitative conversion at r.T and ensures total regioselectivity toward highly substituted oxazolidone scaffolds. An in-depth rationalization of the high reactivity of these cyclic carbonate structures and of the aminolysis reaction mechanism is provided by a computational study supporting experimental observations. The high efficiency of the reaction is then translated to the deconstruction of high-performance thermoplastics containing tetrasubstituted cyclic carbonate linkages to deliver building blocks that are reused for designing recyclable thermosets bearing dynamic N,S-acetal linkages.
{"title":"Fast, Regioselective Aminolysis of Tetrasubstituted Cyclic Carbonates and Application to Recyclable Thermoplastics and Thermosets","authors":"Thomas Habets, Raphaël Méreau, Fabiana Siragusa, Bruno Grignard, Christophe Detrembleur","doi":"10.1021/acsmacrolett.4c00570","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00570","url":null,"abstract":"Herein, the long-standing challenge of the ring-opening aminolysis of CO<sub>2</sub>-derived tetrasubstituted cyclic carbonates at room temperature (r.T) is overcome under catalyst-free conditions. Molecular design of the cyclic carbonate by substitution of an alkyl group by a thioether unlocks quantitative conversion at r.T and ensures total regioselectivity toward highly substituted oxazolidone scaffolds. An in-depth rationalization of the high reactivity of these cyclic carbonate structures and of the aminolysis reaction mechanism is provided by a computational study supporting experimental observations. The high efficiency of the reaction is then translated to the deconstruction of high-performance thermoplastics containing tetrasubstituted cyclic carbonate linkages to deliver building blocks that are reused for designing recyclable thermosets bearing dynamic <i>N</i>,<i>S</i>-acetal linkages.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142385911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The controlled synthesis of star-shaped bottlebrush polymers with tunable topologies is a challenge. However, such materials may exhibit distinct photoluminescence properties. Bottlebrush polymers have polymerization-induced emission (PIE) properties due to their aggregated side chains, and aggregation-induced emission (AIE) is also a unique luminescent property. In this work, we prepared a variety of highly active alkyne Pd catalysts and polymerized poly(L/D-lactic acid) macromonomers containing polymerizable phenylisocyanide groups as end groups to obtain a variety of topologically structured bottlebrush polymers with controllable molecular weights and narrow molecular weight distributions. Bottlebrush polymers with tetraphenyl ethylene (TPE) units as the core exhibit tunable photoluminescence and circularly polarized luminescence properties. We propose that such properties are due to the unique AIE characteristics of the TPE unit combined with the PIE characteristics of the bottlebrush polymer.
受控合成具有可调拓扑结构的星形底丛聚合物是一项挑战。然而，这类材料可能会表现出与众不同的光致发光特性。底丛聚合物由于其聚集侧链而具有聚合诱导发射（PIE）特性，而聚集诱导发射（AIE）也是一种独特的发光特性。在这项工作中，我们制备了多种高活性炔钯催化剂，并聚合了含有可聚合苯基异氰基团作为端基的聚(L/D-乳酸)大单体，从而获得了多种拓扑结构的瓶丛聚合物，其分子量可控，分子量分布窄。以四苯基乙烯（TPE）单元为核心的底丛聚合物具有可调的光致发光和圆偏振发光特性。我们认为，这些特性是由于 TPE 单元独特的 AIE 特性与底丛聚合物的 PIE 特性相结合而产生的。
{"title":"Helical Star-Shaped Bottlebrush Polymers: From Controlled Synthesis to Tunable Photoluminescence and Circularly Polarized Luminescence","authors":"Shi-Yi Li, Bing-Hui Duan, Na Liu, Jing Luo, Zheng Chen, Zong-Quan Wu","doi":"10.1021/acsmacrolett.4c00508","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00508","url":null,"abstract":"The controlled synthesis of star-shaped bottlebrush polymers with tunable topologies is a challenge. However, such materials may exhibit distinct photoluminescence properties. Bottlebrush polymers have polymerization-induced emission (PIE) properties due to their aggregated side chains, and aggregation-induced emission (AIE) is also a unique luminescent property. In this work, we prepared a variety of highly active alkyne Pd catalysts and polymerized poly(L/D-lactic acid) macromonomers containing polymerizable phenylisocyanide groups as end groups to obtain a variety of topologically structured bottlebrush polymers with controllable molecular weights and narrow molecular weight distributions. Bottlebrush polymers with tetraphenyl ethylene (TPE) units as the core exhibit tunable photoluminescence and circularly polarized luminescence properties. We propose that such properties are due to the unique AIE characteristics of the TPE unit combined with the PIE characteristics of the bottlebrush polymer.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142384470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-08DOI: 10.1021/acsmacrolett.4c00547
Ruihan Lei, Xiang Chen, Ting Li, Xuhui Zhang, Bihua Xia, Weifu Dong, Yang Wang
Clusteroluminescent polymers have the most potential to be used in light conversion agricultural films due to tunable emission wavelength and large-scale production, but they are still limited by shortcomings such as poor stability and sensitivity to melting processes. In this work, we propose a core–shell confined stable clusteroluminescent polymeric nanoparticle strategy with adjustable shell thickness. By the employment of a combination of solvent and heat treatment methods, the structures, rigid-flexible properties, and aggregation states of the core polymer chains have been modified. The presence of cross-linked shells has significantly enhanced the stability of the clusteroluminescent nanoparticles, ensuring that they retain their structure form even after undergoing high temperature and shear. Finally, the stable agricultural light conversion films with tunable clusteroluminescence are obtained via melt blending of the core–shell confined nanoparticles and polyethylene (PE). Due to the shell confinement effect, when melt-blended, the shell can protect the clusteroluminescent polymer within the core from the effects of high temperature and shear. It is anticipated that the completion of this work will provide a significant foundation for the large-scale application of cluster-luminescent polymers in agriculture.
{"title":"Core–Shell Confined Stable Polymer Nanoparticles with Tunable Clusteroluminescence","authors":"Ruihan Lei, Xiang Chen, Ting Li, Xuhui Zhang, Bihua Xia, Weifu Dong, Yang Wang","doi":"10.1021/acsmacrolett.4c00547","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00547","url":null,"abstract":"Clusteroluminescent polymers have the most potential to be used in light conversion agricultural films due to tunable emission wavelength and large-scale production, but they are still limited by shortcomings such as poor stability and sensitivity to melting processes. In this work, we propose a core–shell confined stable clusteroluminescent polymeric nanoparticle strategy with adjustable shell thickness. By the employment of a combination of solvent and heat treatment methods, the structures, rigid-flexible properties, and aggregation states of the core polymer chains have been modified. The presence of cross-linked shells has significantly enhanced the stability of the clusteroluminescent nanoparticles, ensuring that they retain their structure form even after undergoing high temperature and shear. Finally, the stable agricultural light conversion films with tunable clusteroluminescence are obtained via melt blending of the core–shell confined nanoparticles and polyethylene (PE). Due to the shell confinement effect, when melt-blended, the shell can protect the clusteroluminescent polymer within the core from the effects of high temperature and shear. It is anticipated that the completion of this work will provide a significant foundation for the large-scale application of cluster-luminescent polymers in agriculture.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142384471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-08DOI: 10.1021/acsmacrolett.4c00556
McKinley K. Paul, Matthew C. Raeside, Will R. Gutekunst
Polythioesters are attracting increasing interest in applications requiring degradability or recyclability. However, few general methods exist for the synthesis of these polymers. This report presents a fast and versatile method for synthesizing polythioesters from readily available lactone feedstocks. The two-step process begins with the thionation of lactones to thionolactones, followed by the ring-opening polymerization of the thionolactones to polythioesters. Unlike previous methods that rely on harsh reagents to accomplish this transformation, we demonstrate that the mild tetrabutylammonium thioacetate is a competent initiator for polymerization. This method exhibits broad applicability, as demonstrated by the successful polymerizations of an unstrained 17-membered macrocycle and an N-substituted cyclic thionocarbamate. Furthermore, the generality of this scheme enables the synthesis of polythioesters with highly tunable properties, as demonstrated here by the synthesis of a set of polymers with glass transition temperatures spanning 180 °C. Finally, the polythioesters are efficiently depolymerized into the corresponding thiolactones.
在要求可降解或可回收的应用领域，聚硫醚正引起越来越多的关注。然而，合成这些聚合物的通用方法却寥寥无几。本报告介绍了一种利用容易获得的内酯原料合成聚硫醚的快速而通用的方法。该方法分两步进行，首先将内酯亚硫酰化为亚硫酰内酯，然后将亚硫酰内酯开环聚合为聚硫酯。与以往依赖刺激性试剂完成这种转化的方法不同，我们证明了温和的硫代乙酸四丁基铵是一种合格的聚合引发剂。这种方法具有广泛的适用性，成功聚合了一个未受约束的 17 元大环和一个 N-取代环硫代氨基甲酸酯就证明了这一点。此外，这种方法的通用性使得它能够合成具有高度可调特性的聚硫酯，合成出一组玻璃化转变温度超过 180 °C 的聚合物就证明了这一点。最后，聚硫醚可有效地解聚成相应的硫内酯。
{"title":"General and Mild Method for the Synthesis of Polythioesters from Lactone Feedstocks","authors":"McKinley K. Paul, Matthew C. Raeside, Will R. Gutekunst","doi":"10.1021/acsmacrolett.4c00556","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00556","url":null,"abstract":"Polythioesters are attracting increasing interest in applications requiring degradability or recyclability. However, few general methods exist for the synthesis of these polymers. This report presents a fast and versatile method for synthesizing polythioesters from readily available lactone feedstocks. The two-step process begins with the thionation of lactones to thionolactones, followed by the ring-opening polymerization of the thionolactones to polythioesters. Unlike previous methods that rely on harsh reagents to accomplish this transformation, we demonstrate that the mild tetrabutylammonium thioacetate is a competent initiator for polymerization. This method exhibits broad applicability, as demonstrated by the successful polymerizations of an unstrained 17-membered macrocycle and an N-substituted cyclic thionocarbamate. Furthermore, the generality of this scheme enables the synthesis of polythioesters with highly tunable properties, as demonstrated here by the synthesis of a set of polymers with glass transition temperatures spanning 180 °C. Finally, the polythioesters are efficiently depolymerized into the corresponding thiolactones.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142384561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-07DOI: 10.1021/acsmacrolett.4c00550
Alvaro Calderón-Díaz, Andrew C. Boggiano, Wei Xiong, Nadine Kaiser, Will R. Gutekunst
A thiocarbonyl radical ring-opening polymerization approach was implemented with cyclic thionocarbamates to generate degradable copolymers with N-vinyl monomers. The rigid structures of cyclic N-substituted thionocarbamates have been revealed by X-ray crystallography and NMR spectroscopy. The corresponding copolymers show incorporation of the thiocarbamates within the carbon backbone of polyvinylpyrrolidone influenced by acyl substituents through radical ring-opening copolymerization. The phenyl-substituted cyclic thionocarbamate copolymerized with N-vinyl carbazole and N-vinyl caprolactam, while little to no incorporation occurred with tBu acrylate and styrene, respectively. Further, these copolymers can undergo hydrolytic degradation under mild conditions. A new family of cyclic thionocarbamates capable of radical ring-opening copolymerization with N-vinyl monomers has been established.
{"title":"Degradable N-Vinyl Copolymers through Radical Ring-Opening Polymerization of Cyclic Thionocarbamates","authors":"Alvaro Calderón-Díaz, Andrew C. Boggiano, Wei Xiong, Nadine Kaiser, Will R. Gutekunst","doi":"10.1021/acsmacrolett.4c00550","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00550","url":null,"abstract":"A thiocarbonyl radical ring-opening polymerization approach was implemented with cyclic thionocarbamates to generate degradable copolymers with <i>N</i>-vinyl monomers. The rigid structures of cyclic <i>N</i>-substituted thionocarbamates have been revealed by X-ray crystallography and NMR spectroscopy. The corresponding copolymers show incorporation of the thiocarbamates within the carbon backbone of polyvinylpyrrolidone influenced by acyl substituents through radical ring-opening copolymerization. The phenyl-substituted cyclic thionocarbamate copolymerized with <i>N</i>-vinyl carbazole and <i>N</i>-vinyl caprolactam, while little to no incorporation occurred with <sup><i>t</i></sup>Bu acrylate and styrene, respectively. Further, these copolymers can undergo hydrolytic degradation under mild conditions. A new family of cyclic thionocarbamates capable of radical ring-opening copolymerization with <i>N</i>-vinyl monomers has been established.","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142383961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-04DOI: 10.1021/acsmacrolett.4c00476
Jiahao Wu, Feng Cao, Pui Wo Felix Yeung, Manjia Li, Kohji Ohno, To Ngai
This study presents a novel approach utilizing total internal reflection microscopy (TIRM) to effectively characterize the swelling and collapse of polymer brushes in aqueous solutions. Zwitterionic poly(carboxybetaine methacrylate) (PCBMA) and nonionic poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA) brushes are chosen as model systems. By investigation of an intriguing theory-experiment discrepancy observed during the measurement of near-wall hindered diffusion, valuable insights into the compressibility of polymer brushes are obtained, revealing their conformational information in aqueous solution. The results demonstrate that zwitterionic PCBMA brushes exhibit minimal antipolyelectrolyte effects in 0.1-10 mM NaCl solution but undergo significant swelling with increasing pH. On the other hand, nonionic POEGMA brushes exhibit similar responses to ionic strength as weak polyelectrolyte brushes. These unexpected findings enhance our understanding of polymer brushes beyond classical theories. The TIRM-based approach proves to be effective for characterizing polymer brushes and other soft nanomaterials.
{"title":"A Total Internal Reflection Microscopy (TIRM)-Based Approach for Direct Characterization of Polymer Brush Conformational Change in Aqueous Solution.","authors":"Jiahao Wu, Feng Cao, Pui Wo Felix Yeung, Manjia Li, Kohji Ohno, To Ngai","doi":"10.1021/acsmacrolett.4c00476","DOIUrl":"https://doi.org/10.1021/acsmacrolett.4c00476","url":null,"abstract":"<p><p>This study presents a novel approach utilizing total internal reflection microscopy (TIRM) to effectively characterize the swelling and collapse of polymer brushes in aqueous solutions. Zwitterionic poly(carboxybetaine methacrylate) (PCBMA) and nonionic poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA) brushes are chosen as model systems. By investigation of an intriguing theory-experiment discrepancy observed during the measurement of near-wall hindered diffusion, valuable insights into the compressibility of polymer brushes are obtained, revealing their conformational information in aqueous solution. The results demonstrate that zwitterionic PCBMA brushes exhibit minimal antipolyelectrolyte effects in 0.1-10 mM NaCl solution but undergo significant swelling with increasing pH. On the other hand, nonionic POEGMA brushes exhibit similar responses to ionic strength as weak polyelectrolyte brushes. These unexpected findings enhance our understanding of polymer brushes beyond classical theories. The TIRM-based approach proves to be effective for characterizing polymer brushes and other soft nanomaterials.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142370167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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