Multifunctional fillers are greatly required for dental resin composites(DRCs).In this work,a spray dryer with a three-fluid nozzle was applied for the first time to construct high-performance complex nanoparticle clu...Multifunctional fillers are greatly required for dental resin composites(DRCs).In this work,a spray dryer with a three-fluid nozzle was applied for the first time to construct high-performance complex nanoparticle clusters(CNCs)consisting of different functional nanofillers for dental restoration.The application of a three-fluid nozzle can effectively avoid the aggregation of different nanoparticles with opposite zeta potentials before the spray drying process in order to construct regularly shaped CNCs.For a SiO_(2)–ZrO_(2) binary system,the SiO_(2)–ZrO_(2) CNCs constructed using a three-fluid nozzle maintained their excellent mechanical properties((133.3±4.7)MPa,(8.8±0.5)GPa,(371.1±13.3)MPa,and(64.5±0.7)HV for flexural strength,flexural modulus,compressive strength,and hardness of DRCs,respectively),despite the introduction of ZrO_(2) nanoparticles,whereas their counterparts constructed using a two-fluid nozzle showed significantly decreased mechanical properties.Furthermore,heat treatment of the SiO_(2)-ZrO_(2) CNCs significantly improved the mechanical properties and radiopacity of the DRCs.The DRCs containing over 10%mass fraction ZrO_(2) nanoparticles can meet the requirement for radiopaque fillers.More importantly,this method can be expanded to ternary or quaternary systems.DRCs filled with SiO_(2)-ZrO_(2)-ZnO CNCs with a ratio of 56:10:4 displayed high antibacterial activity(antibacterial ratio>99%)in addition to excellent mechanical properties and radiopacity.Thus,the three-fluid nozzle spray drying technique holds great potential for the efficient construction of multifunctional cluster fillers for DRCs.展开更多
Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT gen...Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.展开更多
With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applicatio...With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.展开更多
Although photothermal therapy(PTT)has been developed for fighting cancers,the degradative,toxic,and metabolic nature of photothermal conversion materials(PCMs)has prevented them from being clinically implemented.Takin...Although photothermal therapy(PTT)has been developed for fighting cancers,the degradative,toxic,and metabolic nature of photothermal conversion materials(PCMs)has prevented them from being clinically implemented.Taking advantage of the surface modification strategy of mussel-inspired dopamine chemistry and its excellent photothermal conversion effect,polydopamine(Pdop)represents a versatile PTT platform,providing strategies and methods for the construction of novel Pdop-functionalized PCMs.Thanks to its adhesion and secondary reactivity,Pdop can be deposited on virtually all substrates to improve their bioavailability and biocompatibility.Pdop-based PCMs could not be only functionalized with small biomolecules via chemical bonds and/or noncovalent force but also modified with functional polymers via either the“grafting to”or“grafting from”method.This review highlights the synthetic methods,therapeutic strategies,and designs of PCMs based on Pdop in recent years to explore its scope and limitations.展开更多
Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively us...Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively used to prepare polypeptides.Despite continuous innovations,it is still challenging to synthesize polypeptides in high molecular weight fficiently.To address this challenge,we developed KHMDS/NaHMDS initiated fast NCA polymerization that is also moisture tolerant,open-flask amenable and terminal tunable.This NCA polymerization was able to proceed in most common solvents and meet the solubility requirement of variable NCA monomers and corresponding polypeptides.KHMDS can initiate r benzy-L glutamate-N carboxyanhydride(BLG NCA)polymerization in a reaction rate 92 times faster than does hexylamine and 80 times faster than does triethylamine.This NCA polymerization also demonstrated easy and fast synthesis of gram-scale long chain polypeptides in an open flask.展开更多
A series of cross-linked poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/octavinyloctasilasesquioxane (PHBWOVS) composites were obtained by a simple melt reactive processing technique. Dicumyl peroxide (DCP) and OV...A series of cross-linked poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/octavinyloctasilasesquioxane (PHBWOVS) composites were obtained by a simple melt reactive processing technique. Dicumyl peroxide (DCP) and OVS were employed as a free radical initiator and a cross-linking agent, respectively. The chemical structure of these produced composites were identified by 1H/13C/29Si-nuclear magnetic resonance spectroscopy (1H/13C/29Si-NMR) and Fourier transform infrared spectroscopy (FTIR). The melting behavior, non-isothermal crystallization, spherulite morphology and thermal stability property of PHBV/OVS composites were also investigated. The nucleation behaviors and crystallization rate of PHBV/OVS were significantly enhanced with the formation of cross-linked networks with different side-chains and cross-linking points. The red shift of crystalline peak temperature with addition of a small amount of OVS content evidenced the higher crystalline ability compared with the neat PHBV. However there was a threshold content, beyond which the crystallization rate weakened again. Additionally, the cross-linked structure of PHBV/OVS composites could be adjusted by changing the amount of OVS.展开更多
Naturally occurring fibers,such as cotton,flax,silk,and wool have been utilized by mankind for millennia.The silk gauze gown of Han-dynasty found in 1972 by archaeological discovery in Mawangdui Han Tomb weighs only 4...Naturally occurring fibers,such as cotton,flax,silk,and wool have been utilized by mankind for millennia.The silk gauze gown of Han-dynasty found in 1972 by archaeological discovery in Mawangdui Han Tomb weighs only 49 grams.It demonstrates the advanced silkworm cultivation,harvesting and weaving techniques in the early Han Dynasty in China.Even today,we are not able to replicate this silk gown with such light weight.For a long time.展开更多
基金the National Key Research and Development Program of China(2016YFA0201701)the National Natural Science Foundation of China(21878015).
文摘Multifunctional fillers are greatly required for dental resin composites(DRCs).In this work,a spray dryer with a three-fluid nozzle was applied for the first time to construct high-performance complex nanoparticle clusters(CNCs)consisting of different functional nanofillers for dental restoration.The application of a three-fluid nozzle can effectively avoid the aggregation of different nanoparticles with opposite zeta potentials before the spray drying process in order to construct regularly shaped CNCs.For a SiO_(2)–ZrO_(2) binary system,the SiO_(2)–ZrO_(2) CNCs constructed using a three-fluid nozzle maintained their excellent mechanical properties((133.3±4.7)MPa,(8.8±0.5)GPa,(371.1±13.3)MPa,and(64.5±0.7)HV for flexural strength,flexural modulus,compressive strength,and hardness of DRCs,respectively),despite the introduction of ZrO_(2) nanoparticles,whereas their counterparts constructed using a two-fluid nozzle showed significantly decreased mechanical properties.Furthermore,heat treatment of the SiO_(2)-ZrO_(2) CNCs significantly improved the mechanical properties and radiopacity of the DRCs.The DRCs containing over 10%mass fraction ZrO_(2) nanoparticles can meet the requirement for radiopaque fillers.More importantly,this method can be expanded to ternary or quaternary systems.DRCs filled with SiO_(2)-ZrO_(2)-ZnO CNCs with a ratio of 56:10:4 displayed high antibacterial activity(antibacterial ratio>99%)in addition to excellent mechanical properties and radiopacity.Thus,the three-fluid nozzle spray drying technique holds great potential for the efficient construction of multifunctional cluster fillers for DRCs.
基金financially supported by the Science and Technology Commission of Shanghai Municipality (No.20JC1414900)the National Natural Science Foundation of China (No.52203005)the Science and Technology Commission of Shanghai Municipality (No.21ZR1401400)。
文摘Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.
基金supported by the National Natural Science Foundation of China(No.22108031)Shanghai Sailing Program(No.21YF1400800).
文摘With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.
基金financially supported by the National Natural Science Foundation of China(No.52003047)the Science and Technology Commission of Shanghai Municipality(No.20JC1414900)the Fundamental Research Funds for the Central Universities(No.2232020D-05)。
文摘Although photothermal therapy(PTT)has been developed for fighting cancers,the degradative,toxic,and metabolic nature of photothermal conversion materials(PCMs)has prevented them from being clinically implemented.Taking advantage of the surface modification strategy of mussel-inspired dopamine chemistry and its excellent photothermal conversion effect,polydopamine(Pdop)represents a versatile PTT platform,providing strategies and methods for the construction of novel Pdop-functionalized PCMs.Thanks to its adhesion and secondary reactivity,Pdop can be deposited on virtually all substrates to improve their bioavailability and biocompatibility.Pdop-based PCMs could not be only functionalized with small biomolecules via chemical bonds and/or noncovalent force but also modified with functional polymers via either the“grafting to”or“grafting from”method.This review highlights the synthetic methods,therapeutic strategies,and designs of PCMs based on Pdop in recent years to explore its scope and limitations.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21774031 and 21861162010)the National Key Research and Development Program of China(No.2016YFC1100401)+1 种基金Research Program of State Key Laboratory of Bioreactor Enginering,State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University,the Fundamental Research Funds for the Central Universities(Nos.22221818014 and 50321041917001)The authors also thank Research Center of Analysis and Test of East China University of Science and Technology for the help on the characterization.
文摘Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively used to prepare polypeptides.Despite continuous innovations,it is still challenging to synthesize polypeptides in high molecular weight fficiently.To address this challenge,we developed KHMDS/NaHMDS initiated fast NCA polymerization that is also moisture tolerant,open-flask amenable and terminal tunable.This NCA polymerization was able to proceed in most common solvents and meet the solubility requirement of variable NCA monomers and corresponding polypeptides.KHMDS can initiate r benzy-L glutamate-N carboxyanhydride(BLG NCA)polymerization in a reaction rate 92 times faster than does hexylamine and 80 times faster than does triethylamine.This NCA polymerization also demonstrated easy and fast synthesis of gram-scale long chain polypeptides in an open flask.
基金support of the National Natural Science Foundation of China (No. 51603033)the Fundamental Research Funds for the Central Universities (Nos. 2232018A3-01 and 2232018D3-03)+2 种基金the Program for Innovative Research Team in University of Ministry of Education of China (No. IRT16R13)the Open Foundation of Key Laboratory of Advanced Textile Materials and Manufacturing Technology (Zhejiang Sci-Tech University)Education Ministry of China (No. 2017001)
文摘A series of cross-linked poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/octavinyloctasilasesquioxane (PHBWOVS) composites were obtained by a simple melt reactive processing technique. Dicumyl peroxide (DCP) and OVS were employed as a free radical initiator and a cross-linking agent, respectively. The chemical structure of these produced composites were identified by 1H/13C/29Si-nuclear magnetic resonance spectroscopy (1H/13C/29Si-NMR) and Fourier transform infrared spectroscopy (FTIR). The melting behavior, non-isothermal crystallization, spherulite morphology and thermal stability property of PHBV/OVS composites were also investigated. The nucleation behaviors and crystallization rate of PHBV/OVS were significantly enhanced with the formation of cross-linked networks with different side-chains and cross-linking points. The red shift of crystalline peak temperature with addition of a small amount of OVS content evidenced the higher crystalline ability compared with the neat PHBV. However there was a threshold content, beyond which the crystallization rate weakened again. Additionally, the cross-linked structure of PHBV/OVS composites could be adjusted by changing the amount of OVS.
文摘Naturally occurring fibers,such as cotton,flax,silk,and wool have been utilized by mankind for millennia.The silk gauze gown of Han-dynasty found in 1972 by archaeological discovery in Mawangdui Han Tomb weighs only 49 grams.It demonstrates the advanced silkworm cultivation,harvesting and weaving techniques in the early Han Dynasty in China.Even today,we are not able to replicate this silk gown with such light weight.For a long time.