A family of new triphenylmethane(TPM)-based polyimides(PIs)containing bulky tert-butyldimethylsiloxy(TBS)side-groups(PI-TPMOSis)has been prepared by a post-polymerization modification via a simple silyl ether reaction...A family of new triphenylmethane(TPM)-based polyimides(PIs)containing bulky tert-butyldimethylsiloxy(TBS)side-groups(PI-TPMOSis)has been prepared by a post-polymerization modification via a simple silyl ether reaction of TPM-based PIs containing hydroxyl(OH)groups(PI-TPMOHs).The attachment of TBS side-groups in PI-TPMOSis can be achieved up to 100%,as confirmed by the 1H-NMR and IR spectra.Due to the presence of the TPM structure,PI-TPMOSi films still display the excellent thermal stability with high glass transition temperature(Tg)of 314–351°C and high degradation temperature(Td5%)of 480–501°C.It is quite remarkable that the introduction of TBS side-groups into PI-TPMOSi chains results in more superior optical,dielectric and solubility properties in comparison with the precursor PI-TPMOH films,probably due to the reductions of the packing density and charge-transfer complexes(CTCs)formation.The optical transmittance at 400 nm(T400)of PI-TPMOSi films is significantly increased from 45.3%–68.8%to 75.4%–81.6%of the precursor PI-TPMOH films.The dielectric constant(Dk)and dissipation factor(Df)at 1 MHz of PI-TPMOSi films are reduced from 4.11–4.40 and 0.00159–0.00235 to 2.61–2.92 and 0.00125–0.00171 of the precursor PI-TPMOH films,respectively.Combining the molecular design and simple preparation method,this study provides an effective approach for enhancement of various properties of PI films for microelectronic and photoelectric engineering applications.展开更多
Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great signif...Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance.In this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological stability.Furthermore,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high efficiency.This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.展开更多
Polymerization of 2-(4-halophenyl)-1,3-butadiene(2-XPB) and their copolymerization with isoprene using a yttrium catalyst have been examined. The β-diketiminato yttrium bis(alkyl) complex(1) activated by [Ph_3 C][B(C...Polymerization of 2-(4-halophenyl)-1,3-butadiene(2-XPB) and their copolymerization with isoprene using a yttrium catalyst have been examined. The β-diketiminato yttrium bis(alkyl) complex(1) activated by [Ph_3 C][B(C_(6) F_(5))_(4)] and Ali Bu3 shows high cis-1,4-selectivity(>98%) for the polymerization of 2-XPB(2-XPB = 2-FPB, 2-Cl PB and 2-Br PB) to afford halogenated plastic poly(dienes) with glass transition temperatures of30–55 ℃. Moreover, the copolymerization of 2-XPB with isoprene(IP) has also been achieved by this catalyst, and the insertion ratios of 2-XPB can be facilely tuned in a full range of 0%–100% simply by changing the 2-XPB-to-IP ratio. Quantitative hydrogenation of cis-1,4-poly(2-XPB) results in perfect alternating ethylene-halostyrene copolymers, and an alternating copolymer of 4-vinylbenzoic acid with ethylene is obtained by a consecutive reaction of ethylene-4-bromostyrene copolymer with ^(n)Bu Li, CO_(2) and HCl.展开更多
Incorporating fluorophores into polymeric nanoparticles has been testified as a feasible way to improve the emitting property and bio-compatibility of nano-emitters, which can be applied as fluorescent probes in label...Incorporating fluorophores into polymeric nanoparticles has been testified as a feasible way to improve the emitting property and bio-compatibility of nano-emitters, which can be applied as fluorescent probes in labeling cells for imaging. Plenty of efforts have been made on the above direction. However, the size effect of nano-emitters has not been addressed yet mainly given the difficulties in controlling morphology and size of the assemblies. In our preceding study, we employed post-polymerization modification method for preparing amphiphilic copolymers, and obtained core-shell(the hydrophobic fluorophores are wrapped inside the nanoparticle to form the core) assemblies in aqueous solution. By this method, we are able to regulate the ratio of the hydrophilic/hydrophobic moieties, and thus alternate the size of the assemblies in a rather simple way. In this study, we synthesized a series of random copolymers by changing the ratio of poly(ethylene glycol) to tetraphenylethylene groups. Notably, the number of repeating units of the polymer was controlled constant for all the copolymers. The self-assembly of these copolymers resulted in different sizes of nanoparticles, and the size decreased with the decreasing fraction of poly(ethylene glycol). Interestingly, the emission of the nanoparticles showed size dependence, and smaller diameter corresponded to stronger emission. Being cultured with HeLa cells, either the large(diameter of ~300 nm) or the small(diameter of ~180 nm) nano-emitters allowed for very high cell viabilities up to 25 μg·mL-1. Both of them can be applied in cell imaging and provide high contrast fluorescent images.展开更多
In contrast to conventional main-chain conjugated polymers, incorporation of electronically active conjugated oligomers into non-conjugated polymer backbones as pendant groups represents a promising alternative strate...In contrast to conventional main-chain conjugated polymers, incorporation of electronically active conjugated oligomers into non-conjugated polymer backbones as pendant groups represents a promising alternative strategy to developing novel electroactive polymer materials that are desirable for potential applications in organic electronics. This review focuses on polymers with thiophene in the side chain and summarizes the most important synthetic approaches to these polymers, including direct controlled polymerization techniques(e.g., ATRP, ROMP, and RAFT) as well as post-polymerization modifications. Additionally, various properties and applications of these polymers are discussed.展开更多
Secrecy has received tremendous attention in modern information society. Innovative polymer-based fluorescent materials with multiple mode emission are quite desirable to achieve multistage data security. Herein, a se...Secrecy has received tremendous attention in modern information society. Innovative polymer-based fluorescent materials with multiple mode emission are quite desirable to achieve multistage data security. Herein, a series of soluble and thermally stable hyperbranched poly(formyl-1,2,3-triazole)s(hb-PFTAs) with high molecular weights were facilely prepared by catalyst-free polycycloaddition of aldehyde-activated internal triyne and diazides. Functional moieties of triphenylamine and binaphthyl could be incorporated into the polymers to offer them with unique fluorescence and circular dichroism properties, respectively.By taking advantage of activated ethynyl and aldehyde groups on their peripheries and in the internal branch chains, the hbPFTAs can undergo efficient single-and double-stage post-functionalization. More importantly, based on the remarkable fluorescence responses to hydrazine and hydrochloric acid, the hyperbranched polymers are featured with triple-mode fluorescent patterns and have been applied in quadruple-modal information encryption and storage with enhanced security and density. Collectively, this work not only enriches the structural diversity of the existing triazole-based material library, but also provides new polymeric materials for data and information security application.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52203014,52103010 and 52003200)the Guangdong Basic and Applied Basic Research Foundation(Nos.2020A1515110767,2022A1515010969,2020A1515110897 and 2023A1515010999)+2 种基金the Open Fund for Key Lab of Guangdong High Property and Functional Macromolecular Materials,China(No.20220601)Guangdong Provincial Department of Education Featured Innovation Project(No.2021KTSCX138)the Science Foundation for Young Research Groups of Wuyi University(Nos.2020AL016 and 2019AL019).
文摘A family of new triphenylmethane(TPM)-based polyimides(PIs)containing bulky tert-butyldimethylsiloxy(TBS)side-groups(PI-TPMOSis)has been prepared by a post-polymerization modification via a simple silyl ether reaction of TPM-based PIs containing hydroxyl(OH)groups(PI-TPMOHs).The attachment of TBS side-groups in PI-TPMOSis can be achieved up to 100%,as confirmed by the 1H-NMR and IR spectra.Due to the presence of the TPM structure,PI-TPMOSi films still display the excellent thermal stability with high glass transition temperature(Tg)of 314–351°C and high degradation temperature(Td5%)of 480–501°C.It is quite remarkable that the introduction of TBS side-groups into PI-TPMOSi chains results in more superior optical,dielectric and solubility properties in comparison with the precursor PI-TPMOH films,probably due to the reductions of the packing density and charge-transfer complexes(CTCs)formation.The optical transmittance at 400 nm(T400)of PI-TPMOSi films is significantly increased from 45.3%–68.8%to 75.4%–81.6%of the precursor PI-TPMOH films.The dielectric constant(Dk)and dissipation factor(Df)at 1 MHz of PI-TPMOSi films are reduced from 4.11–4.40 and 0.00159–0.00235 to 2.61–2.92 and 0.00125–0.00171 of the precursor PI-TPMOH films,respectively.Combining the molecular design and simple preparation method,this study provides an effective approach for enhancement of various properties of PI films for microelectronic and photoelectric engineering applications.
基金financially supported by the Scientific Research Start-up Fund Project of Anhui Polytechnic University for Introducing Talents(No.2022YQQ081)Natural Science Research Project of Anhui Educational Committee(No.2024AH050133)the National Natural Science Foundation of China(No.22001078).
文摘Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance.In this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological stability.Furthermore,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high efficiency.This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.
基金financially supported by the National Natural Science Foundation of China (Nos. 21634007 and 51773193)the Department of Science and Technology of Jilin Province(No. 20180101171JC)。
文摘Polymerization of 2-(4-halophenyl)-1,3-butadiene(2-XPB) and their copolymerization with isoprene using a yttrium catalyst have been examined. The β-diketiminato yttrium bis(alkyl) complex(1) activated by [Ph_3 C][B(C_(6) F_(5))_(4)] and Ali Bu3 shows high cis-1,4-selectivity(>98%) for the polymerization of 2-XPB(2-XPB = 2-FPB, 2-Cl PB and 2-Br PB) to afford halogenated plastic poly(dienes) with glass transition temperatures of30–55 ℃. Moreover, the copolymerization of 2-XPB with isoprene(IP) has also been achieved by this catalyst, and the insertion ratios of 2-XPB can be facilely tuned in a full range of 0%–100% simply by changing the 2-XPB-to-IP ratio. Quantitative hydrogenation of cis-1,4-poly(2-XPB) results in perfect alternating ethylene-halostyrene copolymers, and an alternating copolymer of 4-vinylbenzoic acid with ethylene is obtained by a consecutive reaction of ethylene-4-bromostyrene copolymer with ^(n)Bu Li, CO_(2) and HCl.
基金financially supported by the National Natural Science Foundation of China (Nos. 21674075 and 21233003)the Natural Science Foundation of Jiangsu Province (No.BK20161211)+1 种基金Key University Science Research Project of Jiangsu Province (No. 17KJA150007)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Incorporating fluorophores into polymeric nanoparticles has been testified as a feasible way to improve the emitting property and bio-compatibility of nano-emitters, which can be applied as fluorescent probes in labeling cells for imaging. Plenty of efforts have been made on the above direction. However, the size effect of nano-emitters has not been addressed yet mainly given the difficulties in controlling morphology and size of the assemblies. In our preceding study, we employed post-polymerization modification method for preparing amphiphilic copolymers, and obtained core-shell(the hydrophobic fluorophores are wrapped inside the nanoparticle to form the core) assemblies in aqueous solution. By this method, we are able to regulate the ratio of the hydrophilic/hydrophobic moieties, and thus alternate the size of the assemblies in a rather simple way. In this study, we synthesized a series of random copolymers by changing the ratio of poly(ethylene glycol) to tetraphenylethylene groups. Notably, the number of repeating units of the polymer was controlled constant for all the copolymers. The self-assembly of these copolymers resulted in different sizes of nanoparticles, and the size decreased with the decreasing fraction of poly(ethylene glycol). Interestingly, the emission of the nanoparticles showed size dependence, and smaller diameter corresponded to stronger emission. Being cultured with HeLa cells, either the large(diameter of ~300 nm) or the small(diameter of ~180 nm) nano-emitters allowed for very high cell viabilities up to 25 μg·mL-1. Both of them can be applied in cell imaging and provide high contrast fluorescent images.
基金supported by the Office of Naval Research(N000141110191)South Carolina National Aeronautics and Space Administration Experimental Program to Stimulate Competitive Research(22-NE-USC_Tang)
文摘In contrast to conventional main-chain conjugated polymers, incorporation of electronically active conjugated oligomers into non-conjugated polymer backbones as pendant groups represents a promising alternative strategy to developing novel electroactive polymer materials that are desirable for potential applications in organic electronics. This review focuses on polymers with thiophene in the side chain and summarizes the most important synthetic approaches to these polymers, including direct controlled polymerization techniques(e.g., ATRP, ROMP, and RAFT) as well as post-polymerization modifications. Additionally, various properties and applications of these polymers are discussed.
基金supported by the National Natural Science Foundation of China(21788102,21901075)the Natural Science Foundation of Guangdong Province(2016A030312002,2019B030301003)+1 种基金the Innovation and Technology Commission of Hong Kong(ITCCNERC14S01)support from the China Postdoctoral Science Foundation(2019M662889)。
文摘Secrecy has received tremendous attention in modern information society. Innovative polymer-based fluorescent materials with multiple mode emission are quite desirable to achieve multistage data security. Herein, a series of soluble and thermally stable hyperbranched poly(formyl-1,2,3-triazole)s(hb-PFTAs) with high molecular weights were facilely prepared by catalyst-free polycycloaddition of aldehyde-activated internal triyne and diazides. Functional moieties of triphenylamine and binaphthyl could be incorporated into the polymers to offer them with unique fluorescence and circular dichroism properties, respectively.By taking advantage of activated ethynyl and aldehyde groups on their peripheries and in the internal branch chains, the hbPFTAs can undergo efficient single-and double-stage post-functionalization. More importantly, based on the remarkable fluorescence responses to hydrazine and hydrochloric acid, the hyperbranched polymers are featured with triple-mode fluorescent patterns and have been applied in quadruple-modal information encryption and storage with enhanced security and density. Collectively, this work not only enriches the structural diversity of the existing triazole-based material library, but also provides new polymeric materials for data and information security application.
