Pub Date : 2024-04-16DOI: 10.1021/acsmacrolett.4c00147
Arpan Pal, Allison R. Wong and Jessica R. Lamb*,
The development of robust methods for the synthesis of chemically recyclable polymers with tunable properties is necessary for the design of next-generation materials. Polyoxazolidinones (POxa), polymers with five-membered urethanes in their backbones, are an attractive target because they are strongly polar and have high thermal stability, but existing step-growth syntheses limit molar masses and methods to chemically recycle POxa to monomer are rare. Herein, we report the synthesis of high molar mass POxa via ring-opening metathesis polymerization of oxazolidinone-fused cyclooctenes. These novel polymers show <5% mass loss up to 382–411 °C and have tunable glass transition temperatures (14–48 °C) controlled by the side chain structure. We demonstrate facile chemical recycling to monomer and repolymerization despite moderately high monomer ring-strain energies, which we hypothesize are facilitated by the conformational restriction introduced by the fused oxazolidinone ring. This method represents the first chain growth synthesis of POxa and provides a versatile platform for the study and application of this emerging subclass of polyurethanes.
{"title":"Chemically Recyclable, High Molar Mass Polyoxazolidinones via Ring-Opening Metathesis Polymerization","authors":"Arpan Pal, Allison R. Wong and Jessica R. Lamb*, ","doi":"10.1021/acsmacrolett.4c00147","DOIUrl":"10.1021/acsmacrolett.4c00147","url":null,"abstract":"<p >The development of robust methods for the synthesis of chemically recyclable polymers with tunable properties is necessary for the design of next-generation materials. Polyoxazolidinones (POxa), polymers with five-membered urethanes in their backbones, are an attractive target because they are strongly polar and have high thermal stability, but existing step-growth syntheses limit molar masses and methods to chemically recycle POxa to monomer are rare. Herein, we report the synthesis of high molar mass POxa via ring-opening metathesis polymerization of oxazolidinone-fused cyclooctenes. These novel polymers show <5% mass loss up to 382–411 °C and have tunable glass transition temperatures (14–48 °C) controlled by the side chain structure. We demonstrate facile chemical recycling to monomer and repolymerization despite moderately high monomer ring-strain energies, which we hypothesize are facilitated by the conformational restriction introduced by the fused oxazolidinone ring. This method represents the first chain growth synthesis of POxa and provides a versatile platform for the study and application of this emerging subclass of polyurethanes.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140556565","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}
Synchronously improving the photothermal conversion efficiency and photodynamic activity of organic small molecule photosensitizers is crucial for their further wide application in cancer treatment. Recently, the emerging A–D–A photosensitizer-based phototherapy systems have attracted great interest due to their plentiful inherent merits. Herein, we propose a design strategy for A–D–A photosensitizers with synchronously enhanced photothermal conversion and reactive oxygen species (ROS) generation efficiencies. Side chain programming is carried out to design three A–D–A photosensitizers (IDT-H, IDT-Br, IDT-I) containing hexyl, bromohexyl, and iodohexyl side chains, respectively. Theoretical calculations confirm that a bulky iodine atom could weaken the intermolecular π–π stacking and enhance spin–orbit coupling constants of IDT-I. These molecular mechanisms enable IDT-I nanoparticles (NPs) to exhibit 2.4-fold and 1.7-fold higher ROS generation efficiency than that of IDT-H NPs and IDT-Br NPs, respectively, as well as the highest photothermal conversion efficiency. Both the experimental results in vitro and in vivo verify that IDT-I NPs are perfectly qualified for the mission of photothermal and photodynamic synergistic therapy. Therefore, in this contribution, we provide a promising perspective for the design of A–D–A photosensitizers with simultaneously improved photothermal and photodynamic therapy ability.
{"title":"Side Chain Programming Synchronously Enhances the Photothermal Conversion Efficiency and Photodynamic Activity of A–D–A Photosensitizers","authors":"Jiachen Xia, Hui Quan, Yuying Huang, Zhecheng Zhang, Yuehua Zhang* and Bing Lu*, ","doi":"10.1021/acsmacrolett.4c00031","DOIUrl":"10.1021/acsmacrolett.4c00031","url":null,"abstract":"<p >Synchronously improving the photothermal conversion efficiency and photodynamic activity of organic small molecule photosensitizers is crucial for their further wide application in cancer treatment. Recently, the emerging A–D–A photosensitizer-based phototherapy systems have attracted great interest due to their plentiful inherent merits. Herein, we propose a design strategy for A–D–A photosensitizers with synchronously enhanced photothermal conversion and reactive oxygen species (ROS) generation efficiencies. Side chain programming is carried out to design three A–D–A photosensitizers (IDT-H, IDT-Br, IDT-I) containing hexyl, bromohexyl, and iodohexyl side chains, respectively. Theoretical calculations confirm that a bulky iodine atom could weaken the intermolecular π–π stacking and enhance spin–orbit coupling constants of IDT-I. These molecular mechanisms enable IDT-I nanoparticles (NPs) to exhibit 2.4-fold and 1.7-fold higher ROS generation efficiency than that of IDT-H NPs and IDT-Br NPs, respectively, as well as the highest photothermal conversion efficiency. Both the experimental results <i>in vitro</i> and <i>in vivo</i> verify that IDT-I NPs are perfectly qualified for the mission of photothermal and photodynamic synergistic therapy. Therefore, in this contribution, we provide a promising perspective for the design of A–D–A photosensitizers with simultaneously improved photothermal and photodynamic therapy ability.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140547515","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 : 2024-04-12DOI: 10.1021/acsmacrolett.4c00070
Jingcheng Xu, Yulun Wu, Yu Xia, Rida Fatima, Yuesheng Li and Dong-Po Song*,
Prior studies on photonic pigments of amphiphilic bottlebrush block copolymers (BBCPs) through an organized spontaneous emulsification (OSE) mechanism have been limited to using polyethylene glycol (PEG) as the hydrophilic side chains and toluene as the organic phase. Herein, a family of polystyrene-block-polyvinylpyrrolidone (PS-b-PVP) BBCPs are synthesized with PVP as the hydrophilic block. Biocompatible and sustainable anisole is employed for dissolving the obtained BBCPs followed by emulsification of the solutions in water. Subsequent evaporation of oil-in-water emulsion droplets triggers the OSE mechanism, producing thermodynamically stable water-in-oil-in-water (w/o/w) multiple emulsions with uniform and closely packed internal droplet arrays through the assembly of the BBCPs at the w/o interface. Upon solidification, the homogeneous porous structures are formed within the photonic microparticles that exhibit visible structural colors. The pore diameter is widely tunable (150∼314 nm) by changing the degree of polymerization of BBCP (69∼110), resulting in tunable colors across the whole visible spectrum. This work demonstrates useful knowledge that OSE can be generally used in the fabrication of ordered porous materials with tunable internal functional groups, not only for photonic applications, but also offers a potential platform for catalysis, sensing, separation, encapsulation, etc.
之前通过有组织自发乳化(OSE)机制对两亲性瓶丛嵌段共聚物(BBCPs)的光子颜料进行的研究仅限于使用聚乙二醇(PEG)作为亲水侧链和甲苯作为有机相。本文以 PVP 为亲水嵌段,合成了一系列聚苯乙烯-嵌段-聚乙烯吡咯烷酮(PS-b-PVP)BBCPs。使用生物相容性和可持续发展的苯甲醚溶解所获得的 BBCP,然后将溶液乳化在水中。随后水包油乳液液滴的蒸发触发了 OSE 机制,通过 BBCPs 在水包油界面的组装,产生了热力学上稳定的水包油(w/o/w)多重乳液,其内部液滴阵列均匀且紧密。凝固后,光子微粒内部形成均匀的多孔结构,呈现出可见的结构颜色。通过改变 BBCP 的聚合度(69∼110),孔径可进行大范围调节(150∼314 nm),从而在整个可见光谱范围内形成可调节的颜色。这项工作提供了有用的知识,即 OSE 可普遍用于制造具有可调内部官能团的有序多孔材料,不仅可用于光子应用,还为催化、传感、分离、封装等提供了一个潜在的平台。
{"title":"Photonic Pigments of Polystyrene-block-Polyvinylpyrrolidone Bottlebrush Block Copolymers via Sustainable Organized Spontaneous Emulsification","authors":"Jingcheng Xu, Yulun Wu, Yu Xia, Rida Fatima, Yuesheng Li and Dong-Po Song*, ","doi":"10.1021/acsmacrolett.4c00070","DOIUrl":"10.1021/acsmacrolett.4c00070","url":null,"abstract":"<p >Prior studies on photonic pigments of amphiphilic bottlebrush block copolymers (BBCPs) through an organized spontaneous emulsification (OSE) mechanism have been limited to using polyethylene glycol (PEG) as the hydrophilic side chains and toluene as the organic phase. Herein, a family of polystyrene-<i>block</i>-polyvinylpyrrolidone (PS-<i>b</i>-PVP) BBCPs are synthesized with PVP as the hydrophilic block. Biocompatible and sustainable anisole is employed for dissolving the obtained BBCPs followed by emulsification of the solutions in water. Subsequent evaporation of oil-in-water emulsion droplets triggers the OSE mechanism, producing thermodynamically stable water-in-oil-in-water (w/o/w) multiple emulsions with uniform and closely packed internal droplet arrays through the assembly of the BBCPs at the w/o interface. Upon solidification, the homogeneous porous structures are formed within the photonic microparticles that exhibit visible structural colors. The pore diameter is widely tunable (150∼314 nm) by changing the degree of polymerization of BBCP (69∼110), resulting in tunable colors across the whole visible spectrum. This work demonstrates useful knowledge that OSE can be generally used in the fabrication of ordered porous materials with tunable internal functional groups, not only for photonic applications, but also offers a potential platform for catalysis, sensing, separation, encapsulation, etc.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140547443","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 : 2024-04-09DOI: 10.1021/acsmacrolett.4c00041
Peihan Lyu, Zhaoyu Ding, Masao Doi* and Xingkun Man*,
A sheet of glassy polymers placed in a solvent shows swelling behaviors quite different from that of soft polymers (rubbers and gels). (1) Non-Fickian diffusion (called case II diffusion): As solvent permeates into the sample, a sharp front is created between the swollen part and the glassy part, and it moves toward the center at constant speed. (2) Nonmonotonous swelling: The thickness of the sample first increases and then decreases toward the equilibrium value. Here we propose a theory to explain such anomalous behavior by extending the previous theory for swelling of soft gels. We regard the material as a continuum mixture of a glassy polymer network and solvent. We assume that the polymer network is a viscoelastic gel of glassy polymers, and its relaxation time depends strongly on solvent concentration. We show that this theory explains the above two characteristics of glassy polymers in a simple and unified framework. The theory predicts how the permeation speed of the solvent and the characteristic times of the swelling process depend on material parameters and experimental conditions, which can be checked experimentally.
将玻璃状聚合物薄片置于溶剂中,其膨胀行为与软聚合物(橡胶和凝胶)的膨胀行为截然不同。(1) 非费克式扩散(称为情况 II 扩散):当溶剂渗入样品时,在膨胀部分和玻璃状部分之间会形成一个锋面,并以恒定的速度向中心移动。(2) 非单调膨胀:样品的厚度先是增加,然后向平衡值减小。在此,我们通过扩展之前的软凝胶膨胀理论,提出一种理论来解释这种反常行为。我们将材料视为玻璃态聚合物网络和溶剂的连续混合物。我们假设聚合物网络是玻璃态聚合物的粘弹性凝胶,其弛豫时间与溶剂浓度密切相关。我们的研究表明,这一理论可以在一个简单而统一的框架内解释玻璃态聚合物的上述两个特性。该理论预测了溶剂的渗透速度和溶胀过程的特征时间如何依赖于材料参数和实验条件,这些都可以通过实验来验证。
{"title":"A Unified Model for Non-Fickian Diffusion and Anomalous Swelling of Glassy Polymer Gels","authors":"Peihan Lyu, Zhaoyu Ding, Masao Doi* and Xingkun Man*, ","doi":"10.1021/acsmacrolett.4c00041","DOIUrl":"10.1021/acsmacrolett.4c00041","url":null,"abstract":"<p >A sheet of glassy polymers placed in a solvent shows swelling behaviors quite different from that of soft polymers (rubbers and gels). (1) Non-Fickian diffusion (called case II diffusion): As solvent permeates into the sample, a sharp front is created between the swollen part and the glassy part, and it moves toward the center at constant speed. (2) Nonmonotonous swelling: The thickness of the sample first increases and then decreases toward the equilibrium value. Here we propose a theory to explain such anomalous behavior by extending the previous theory for swelling of soft gels. We regard the material as a continuum mixture of a glassy polymer network and solvent. We assume that the polymer network is a viscoelastic gel of glassy polymers, and its relaxation time depends strongly on solvent concentration. We show that this theory explains the above two characteristics of glassy polymers in a simple and unified framework. The theory predicts how the permeation speed of the solvent and the characteristic times of the swelling process depend on material parameters and experimental conditions, which can be checked experimentally.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140538983","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 : 2024-04-09DOI: 10.1021/acsmacrolett.4c00063
Rui Yuan, Zhao Fang, Fang Liu, Xianzhe He, Sa Du, Nan Zhang, Qiang Zeng, Yen Wei, Yuwei Wu* and Lei Tao*,
The development of antioxidant wound dressings to remove excessive free radicals around wounds is essential for wound healing. In this study, we developed an efficient strategy to prepare antioxidant self-healing hydrogels as wound dressings by combining multicomponent reactions (MCRs) and postpolymerization modification. A polymer containing ferrocene and phenylboronic acid groups was developed via the Biginelli reaction, followed by efficient modification. This polymer is antioxidant due to its ferrocene moieties and can rapidly cross-link poly(vinyl alcohol) to realize an antioxidant self-healing hydrogel through dynamic borate ester linkages. This hydrogel has low cytotoxicity and is biocompatible. In in vivo experiments, this hydrogel is superior to existing clinical dressings in promoting wound healing. This study demonstrates the value of the Biginelli reaction in exploring biomaterials, potentially offering insights into the design of other multifunctional polymers and related materials using different MCRs.
{"title":"Ferrocene-Based Antioxidant Self-Healing Hydrogel via the Biginelli Reaction for Wound Healing","authors":"Rui Yuan, Zhao Fang, Fang Liu, Xianzhe He, Sa Du, Nan Zhang, Qiang Zeng, Yen Wei, Yuwei Wu* and Lei Tao*, ","doi":"10.1021/acsmacrolett.4c00063","DOIUrl":"10.1021/acsmacrolett.4c00063","url":null,"abstract":"<p >The development of antioxidant wound dressings to remove excessive free radicals around wounds is essential for wound healing. In this study, we developed an efficient strategy to prepare antioxidant self-healing hydrogels as wound dressings by combining multicomponent reactions (MCRs) and postpolymerization modification. A polymer containing ferrocene and phenylboronic acid groups was developed via the Biginelli reaction, followed by efficient modification. This polymer is antioxidant due to its ferrocene moieties and can rapidly cross-link poly(vinyl alcohol) to realize an antioxidant self-healing hydrogel through dynamic borate ester linkages. This hydrogel has low cytotoxicity and is biocompatible. In <i>in vivo</i> experiments, this hydrogel is superior to existing clinical dressings in promoting wound healing. This study demonstrates the value of the Biginelli reaction in exploring biomaterials, potentially offering insights into the design of other multifunctional polymers and related materials using different MCRs.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140538283","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 : 2024-04-04DOI: 10.1021/acsmacrolett.4c00059
Kriti Kapil, Hironobu Murata, Grzegorz Szczepaniak, Alan J. Russell and Krzysztof Matyjaszewski*,
Protein–polymer conjugates combine the unique properties of both proteins and synthetic polymers, making them important materials for biomedical applications. In this work, we synthesized and characterized protein-branched polymer bioconjugates that were precisely designed to retain protein functionality while preventing unwanted interactions. Using chymotrypsin as a model protein, we employed a controlled radical branching polymerization (CRBP) technique utilizing a water-soluble inibramer, sodium 2-bromoacrylate. The green-light-induced atom transfer radical polymerization (ATRP) enabled the grafting of branched polymers directly from the protein surface in the open air. The resulting bioconjugates exhibited a predetermined molecular weight, well-defined architecture, and high branching density. Conformational analysis by SEC-MALS validated the controlled grafting of branched polymers. Furthermore, enzymatic assays revealed that densely grafted polymers prevented protein inhibitor penetration, and the resulting conjugates retained up to 90% of their enzymatic activity. This study demonstrates a promising strategy for designing protein–polymer bioconjugates with tunable sieving behavior, opening avenues for applications in drug delivery and biotechnology.
{"title":"Tailored Branched Polymer–Protein Bioconjugates for Tunable Sieving Performance","authors":"Kriti Kapil, Hironobu Murata, Grzegorz Szczepaniak, Alan J. Russell and Krzysztof Matyjaszewski*, ","doi":"10.1021/acsmacrolett.4c00059","DOIUrl":"10.1021/acsmacrolett.4c00059","url":null,"abstract":"<p >Protein–polymer conjugates combine the unique properties of both proteins and synthetic polymers, making them important materials for biomedical applications. In this work, we synthesized and characterized protein-branched polymer bioconjugates that were precisely designed to retain protein functionality while preventing unwanted interactions. Using chymotrypsin as a model protein, we employed a controlled radical branching polymerization (CRBP) technique utilizing a water-soluble inibramer, sodium 2-bromoacrylate. The green-light-induced atom transfer radical polymerization (ATRP) enabled the grafting of branched polymers directly from the protein surface in the open air. The resulting bioconjugates exhibited a predetermined molecular weight, well-defined architecture, and high branching density. Conformational analysis by SEC-MALS validated the controlled grafting of branched polymers. Furthermore, enzymatic assays revealed that densely grafted polymers prevented protein inhibitor penetration, and the resulting conjugates retained up to 90% of their enzymatic activity. This study demonstrates a promising strategy for designing protein–polymer bioconjugates with tunable sieving behavior, opening avenues for applications in drug delivery and biotechnology.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsmacrolett.4c00059","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140533973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Glycopolymer-based supramolecular glycoassemblies with signal-driven cascade morphological deformation and accessible surface engineering toward bioinspired functional glycomaterials have attracted much attention due to their diverse applications in fundamental and practical scenarios. Herein, we achieved the cascade morphological transformation and surface engineering of a nucleobase-containing polymeric glycovesicle through exploiting the bioinspired complementary multiple hydrogen bonds of complementary nucleobases. First, the synthesized thymine-containing glycopolymers (PGal30-b-PTAm249) are capable of self-assembling into well-defined glycovesicles. Several kinds of amphiphilic adenine-containing block copolymers with neutral, positive, and negative charges were synthesized to engineer the glycovesicles through the multiple hydrogen bonds between adenine and thymine. A cascade of morphological transformations from vesicles to ruptured vesicles with tails, to worm-like micelles, and finally to spherical micelles were observed via continuously adding the adenine-containing polymer into the thymine-containing glycovesicles. Furthermore, the surface charge properties of these glyconano-objects can be facilely regulated through incorporating various adenine-containing polymers. This work demonstrates the potential application of a unique bioinspired approach to precisely engineer the morphology and surface properties of glycovesicles for boosting their biological applications.
{"title":"Morphological Transformation and Surface Engineering of Glycovesicles Driven by Bioinspired Hydrogen Bonds of Nucleobases","authors":"Caiyun Yang, Yixuan Du, Qiaoran Li, Xinru Gao, Peng Zha, Wanli Zhan, Ketao Liu, Feihu Bi, Zan Hua* and Guang Yang*, ","doi":"10.1021/acsmacrolett.4c00037","DOIUrl":"10.1021/acsmacrolett.4c00037","url":null,"abstract":"<p >Glycopolymer-based supramolecular glycoassemblies with signal-driven cascade morphological deformation and accessible surface engineering toward bioinspired functional glycomaterials have attracted much attention due to their diverse applications in fundamental and practical scenarios. Herein, we achieved the cascade morphological transformation and surface engineering of a nucleobase-containing polymeric glycovesicle through exploiting the bioinspired complementary multiple hydrogen bonds of complementary nucleobases. First, the synthesized thymine-containing glycopolymers (PGal<sub>30</sub>-<i>b</i>-PTAm<sub>249</sub>) are capable of self-assembling into well-defined glycovesicles. Several kinds of amphiphilic adenine-containing block copolymers with neutral, positive, and negative charges were synthesized to engineer the glycovesicles through the multiple hydrogen bonds between adenine and thymine. A cascade of morphological transformations from vesicles to ruptured vesicles with tails, to worm-like micelles, and finally to spherical micelles were observed via continuously adding the adenine-containing polymer into the thymine-containing glycovesicles. Furthermore, the surface charge properties of these glyconano-objects can be facilely regulated through incorporating various adenine-containing polymers. This work demonstrates the potential application of a unique bioinspired approach to precisely engineer the morphology and surface properties of glycovesicles for boosting their biological applications.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140346518","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 : 2024-03-29DOI: 10.1021/acsmacrolett.3c00756
Xiao-Han Wei, Zong-Pei Wu, Ao Peng, Xue-Ao Zhang, Holger Merlitz, M. Gregory Forest, Chen-Xu Wu and Xue-Zheng Cao*,
The assembly of long-range aligned structures of two-dimensional nanosheets (2DNSs) in polymer nanocomposites (PNCs) is in urgent need for the design of nanoelectronics and lightweight energy-storage materials of high conductivity for electricity or heat. These 2DNS are thin and exhibit thermal fluctuations, leading to an intricate interplay with polymers in which entropic effects can be exploited to facilitate a range of different assemblies. In molecular dynamics simulations of experimentally studied 2DNSs, we show that the layer-forming crystallization of 2DNSs is programmable by regulating the strengths and ranges of polymer-induced entropic depletion attractions between pairs of 2DNSs, as well as between single 2DNSs and a substrate surface, by exclusively tuning the temperature and size of the 2DNS. Enhancing the temperature supports the 2DNS–substrate depletion rather than crystallization of 2DNSs in the bulk, leading to crystallized layers of 2DNSs on the substrate surfaces. On the other hand, the interaction range of the 2DNS–2DNS depletion attraction extends further than the 2DNS–substrate attraction whenever the 2DNS size is well above the correlation length of the polymers, which results in a nonmonotonic dependence of the crystallization layer on the 2DNS size. It is demonstrated that the depletion-tuned crystallization layers of 2DNSs contribute to a conductive channel in which individual lithium ions (Li ions) migrate efficiently through the PNCs. This work provides statistical and dynamical insights into the balance between the 2DNS–2DNS and 2DNS–substrate depletion interactions in polymer–2DNS composites and highlights the possibilities to exploit depletion strategies in order to engineer crystallization processes of 2DNSs and thus to control electrical conductivity.
{"title":"Depletion Strategies for Crystallized Layers of Two-Dimensional Nanosheets to Enhance Lithium-Ion Conductivity in Polymer Nanocomposites","authors":"Xiao-Han Wei, Zong-Pei Wu, Ao Peng, Xue-Ao Zhang, Holger Merlitz, M. Gregory Forest, Chen-Xu Wu and Xue-Zheng Cao*, ","doi":"10.1021/acsmacrolett.3c00756","DOIUrl":"10.1021/acsmacrolett.3c00756","url":null,"abstract":"<p >The assembly of long-range aligned structures of two-dimensional nanosheets (2DNSs) in polymer nanocomposites (PNCs) is in urgent need for the design of nanoelectronics and lightweight energy-storage materials of high conductivity for electricity or heat. These 2DNS are thin and exhibit thermal fluctuations, leading to an intricate interplay with polymers in which entropic effects can be exploited to facilitate a range of different assemblies. In molecular dynamics simulations of experimentally studied 2DNSs, we show that the layer-forming crystallization of 2DNSs is programmable by regulating the strengths and ranges of polymer-induced entropic depletion attractions between pairs of 2DNSs, as well as between single 2DNSs and a substrate surface, by exclusively tuning the temperature and size of the 2DNS. Enhancing the temperature supports the 2DNS–substrate depletion rather than crystallization of 2DNSs in the bulk, leading to crystallized layers of 2DNSs on the substrate surfaces. On the other hand, the interaction range of the 2DNS–2DNS depletion attraction extends further than the 2DNS–substrate attraction whenever the 2DNS size is well above the correlation length of the polymers, which results in a nonmonotonic dependence of the crystallization layer on the 2DNS size. It is demonstrated that the depletion-tuned crystallization layers of 2DNSs contribute to a conductive channel in which individual lithium ions (Li ions) migrate efficiently through the PNCs. This work provides statistical and dynamical insights into the balance between the 2DNS–2DNS and 2DNS–substrate depletion interactions in polymer–2DNS composites and highlights the possibilities to exploit depletion strategies in order to engineer crystallization processes of 2DNSs and thus to control electrical conductivity.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140326015","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 : 2024-03-28DOI: 10.1021/acsmacrolett.3c00743
Takaya Ikami, Hiroyuki Aoki and Takaya Terashima*,
Microphase separation of random copolymers, as well as that of high χ–low N block copolymers, is promising to construct sub-10-nm structures into materials. Herein, we designed statistical copolymers consisting of 2-hydroxyethyl acrylate (HEA) and N-octadecylacrylamide (ODAAm) to produce crystallization and hydrogen bond-assisted lamellar structure materials. The copolymers not only formed a crystalline lamellar structure with 3–4 nm domain spacing but also maintained an amorphous lamellar structure via phase transition above the melting temperature up to approximately 100 °C. The key is to introduce hydrogen-bonding amide junctions between the octadecyl groups and the polymer backbones, by which the polymer chains are physically fixed at the interface of lamellar structures even above the melting temperature. The stabilization of the lamellar structure by the amide units is also supported by the fact that the lamellar structure of all-acrylate random copolymers bearing hydroxyethyl and crystalline octadecyl groups is disordered above the melting temperature. By spin-coating on a silicon substrate, the HEA/ODAAm copolymer formed a multilayered lamellar thin film consisting of a hydrophilic hydroxyethyl/main chain phase and a hydrophobic octadecyl phase. The structure and order–disorder transition were analyzed by neutron reflectivity.
{"title":"Lamellar Microphase Separation and Phase Transition of Hydrogen-Bonding/Crystalline Statistical Copolymers: Amide Functionalization at the Interface","authors":"Takaya Ikami, Hiroyuki Aoki and Takaya Terashima*, ","doi":"10.1021/acsmacrolett.3c00743","DOIUrl":"10.1021/acsmacrolett.3c00743","url":null,"abstract":"<p >Microphase separation of random copolymers, as well as that of high χ–low <i>N</i> block copolymers, is promising to construct sub-10-nm structures into materials. Herein, we designed statistical copolymers consisting of 2-hydroxyethyl acrylate (HEA) and <i>N</i>-octadecylacrylamide (ODAAm) to produce crystallization and hydrogen bond-assisted lamellar structure materials. The copolymers not only formed a crystalline lamellar structure with 3–4 nm domain spacing but also maintained an amorphous lamellar structure via phase transition above the melting temperature up to approximately 100 °C. The key is to introduce hydrogen-bonding amide junctions between the octadecyl groups and the polymer backbones, by which the polymer chains are physically fixed at the interface of lamellar structures even above the melting temperature. The stabilization of the lamellar structure by the amide units is also supported by the fact that the lamellar structure of all-acrylate random copolymers bearing hydroxyethyl and crystalline octadecyl groups is disordered above the melting temperature. By spin-coating on a silicon substrate, the HEA/ODAAm copolymer formed a multilayered lamellar thin film consisting of a hydrophilic hydroxyethyl/main chain phase and a hydrophobic octadecyl phase. The structure and order–disorder transition were analyzed by neutron reflectivity.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140310820","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 : 2024-03-28DOI: 10.1021/acsmacrolett.4c00118
Hiroyuki Kubota, and , Makoto Ouchi*,
In this work, we designed benzyl vinyl ethers carrying alkyl substituents at the benzyl position (i.e., sec-BnVEs) as bulky, reactive, and transformable monomers to realize the alternating cationic copolymerization with an alkyl vinyl ether (VE). In particular, the isopropyl substitution caused not only the bulkiness to suppress the successive propagation but also an enhancement of the vinyl group reactivity to promote crossover propagation with a less bulky VE comonomer. The isopropyl-substituted BnVE (iPr-BnVE) underwent living cationic alternating copolymerization with n-butyl VE (nBVE), and the alternating propagation was strongly suggested by the reactivity ratios. The subsequent deprotection of the sec-benzyl pendant afforded the vinyl alcohol (VA)–nBVE alternating copolymer, and the corresponding statistical copolymer was also synthesized by using the nonsubstituted monomer (BnVE) instead of iPr-BnVE. The alternating copolymer exhibited a higher glass transition temperature, which likely stems from the uniform and efficient hydrogen-bonding formation due to the periodic sequence.
{"title":"Design of sec-Benzyl Vinyl Ethers toward the Synthesis of Alternating Copolymers Composed of Vinyl Alcohol and Vinyl Ether Units","authors":"Hiroyuki Kubota, and , Makoto Ouchi*, ","doi":"10.1021/acsmacrolett.4c00118","DOIUrl":"10.1021/acsmacrolett.4c00118","url":null,"abstract":"<p >In this work, we designed benzyl vinyl ethers carrying alkyl substituents at the benzyl position (i.e., <i>sec</i>-BnVEs) as bulky, reactive, and transformable monomers to realize the alternating cationic copolymerization with an alkyl vinyl ether (VE). In particular, the isopropyl substitution caused not only the bulkiness to suppress the successive propagation but also an enhancement of the vinyl group reactivity to promote crossover propagation with a less bulky VE comonomer. The isopropyl-substituted BnVE (<i>i</i>Pr-BnVE) underwent living cationic alternating copolymerization with <i>n</i>-butyl VE (<i>n</i>BVE), and the alternating propagation was strongly suggested by the reactivity ratios. The subsequent deprotection of the <i>sec</i>-benzyl pendant afforded the vinyl alcohol (VA)–<i>n</i>BVE alternating copolymer, and the corresponding statistical copolymer was also synthesized by using the nonsubstituted monomer (BnVE) instead of <i>i</i>Pr-BnVE. The alternating copolymer exhibited a higher glass transition temperature, which likely stems from the uniform and efficient hydrogen-bonding formation due to the periodic sequence.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":null,"pages":null},"PeriodicalIF":5.8,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140303954","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}