Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacr...Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide materials.Two new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),respectively.The structures of the drag reduction agents were confirmed by IR and1H NMR spectroscopies.The molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/mol.When the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/mol.When the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,respectively.Compared with HPAM,both of the above copolymers presented better drag reduction capacities.展开更多
Polypropylene is commonly used as a binder for ceramic injection molding,and rapid cooling is often encountered during processing.However,the crystallization behavior of polypropylene shows a strong dependence on cool...Polypropylene is commonly used as a binder for ceramic injection molding,and rapid cooling is often encountered during processing.However,the crystallization behavior of polypropylene shows a strong dependence on cooling rate due to its semi-crystalline characteristics.Therefore,the influence of cooling rate on the quality of final product cannot be ignored.In this study,the fast differential scanning calorimetry(FSC)test was performed to study the influence of cooling rate on the non-isothermal crystallization behavior and non-isothermal crystallization kinetics of a copolymer polypropylene(PP BC03B).The results show that the crystallization temperatures and crystallinity decrease as the cooling rate increases.In addition,two exothermic peaks occur when cooling rate ranges from 30 to 300 K·s^(-1),indicating the formation of another crystal phase.Avrami,Ozawa and Mo equations were used to explore the non-isothermal crystallization kinetics,and it can be concluded that the Mo method is suitable for this study.展开更多
Polymer science encompasses a different range of materials critical to industries spanning from packaging to biomedicine. Understanding the synthesis, characterization, and applications of common homopolymers and copo...Polymer science encompasses a different range of materials critical to industries spanning from packaging to biomedicine. Understanding the synthesis, characterization, and applications of common homopolymers and copolymers is fundamental to advancing polymer research and development. In this comprehensive review, we explore various preparation methods, including free radical, anionic, and cationic polymerization, utilized for synthesizing homopolymers and copolymers. Furthermore, we investigate solvent choices commonly employed for polymer characterization, ranging from neat conditions, polar protic and polar aprotic solvents. We also explored characterization techniques, including Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA). In addition to industrial applications, we highlight the diverse biological applications of homopolymers, poly(2-hydroxyethyl methacrylate) (pHEMA) and polystyrene, which find its extensive use in biomedicine. By synthesizing and analyzing this wealth of information, this review aims to provide a comprehensive understanding of the synthesis, characterization, and applications of homopolymers and copolymers, with a particular focus on their biological applications. This holistic approach not only contributes to advancements in polymer science and technology but also fosters innovation in biomedicine, ultimately benefiting human health and well-being.展开更多
Synthesis of a cold flow improver （MAVA-a） for diesel fuel and its effect on solidifying point （SP） and cold filter plugging point （CFPP） of diesel fuels were investigated, The cold flow improver was prepared by...Synthesis of a cold flow improver （MAVA-a） for diesel fuel and its effect on solidifying point （SP） and cold filter plugging point （CFPP） of diesel fuels were investigated, The cold flow improver was prepared by using maleic anhydride （MA） and vinyl acetate （VA） as raw materials, toluene as solvent, dibenzoyl peroxide （BPO） as initiator, through alternating polymerization under nitrogen to obtain a binary-polymer and then through aminolysis by using a higher carbon amine as aminating agent at a temperature of 80 ℃. A cold flow improver was designed and prepared for No. 0 diesel fuel from Zhang Jia-Gang Petrochemical Company according to the contents of n-paraffin and its carbon number distribution in the No. 0 diesel fuel. It was also used together with two kinds of ethene-vinyl acetate copolymer improvers （EVA） separately. The test result showed that the CFPP of the No. 0 diesel fuel could be lowered by 3-5 ℃ when the improver MAVA-a was used. The CFPP was lowered by 8℃ when the improver MAVA-a was used together with EVA-2.展开更多
A novel polypropylene random(PPR)composite materials with optimized properties was developed by addingβ-nucleating compound agents(rare earth complex WBG-2 and aryl amide derivative TMB-5)and ternary compound modifie...A novel polypropylene random(PPR)composite materials with optimized properties was developed by addingβ-nucleating compound agents(rare earth complex WBG-2 and aryl amide derivative TMB-5)and ternary compound modifier(TPE/WBG-2/CaCO_(3)).The effects of differentβ-nucleating agents and ternary compound modifier on the mechanical properties and crystallization behavior of PPR were analyzed.The results show that,compared with pure PPR materials,both WBG-2 and TMB-5 could significantly improve the impact strength of PPR.The crystallization temperature of PPR increased with the addition ofβ-nucleating agent.The modified PPR prepared with ternary compound modifier showed the most excellent comprehensive properties.展开更多
Solid-state lithium(Li) metal batteries overwhelm the lithium-ion batteries by harvesting high energy from Li metal anode with ultrahigh capacities and gaining excellent safety from solid electrolytes.However,the unco...Solid-state lithium(Li) metal batteries overwhelm the lithium-ion batteries by harvesting high energy from Li metal anode with ultrahigh capacities and gaining excellent safety from solid electrolytes.However,the uncontrollable solvents in solid electrolytes usually aggravate poor interfacial contact with lithium metal anode and deteriorate Li^(+) pathways.Here a copolymeric network-structured ion conductor by rationally integrating cellulose nanofibril as a two-in-one functional material is employed to anchor the solvent.Taking advantages of tightly anchoring of cellulose nanofibril to solvent,the asconstructed quasi-solid polymer-based electrolyte offers rapid Li^(+) transport channels and realizes effective Li-dendrite suppression,which enables high ionic conductivity of 1.93 × 10^(-3)S cm^(-1) at room temperature,long-term Li plating/stripping over 1900 h,and high capacity retention of 99%.This work provides a fresh strategy for creating solid electrolytes that meet both high ionic conductivity and interfacial stability requirements for practical solid-state lithium metal battery.展开更多
Ringlike polar monomer maleic, anhydride (MAn) was copolymerized with oligo (oxyethylene) methacrylate (MEO_n), and its effect on ion conduction property of the corresponding polymer-salt complexes was studied. As a c...Ringlike polar monomer maleic, anhydride (MAn) was copolymerized with oligo (oxyethylene) methacrylate (MEO_n), and its effect on ion conduction property of the corresponding polymer-salt complexes was studied. As a consequence the introduction of MAn onto polymer chain retards crystallization of the ether pendants considerably, and improves the ion conductivity to a larger degree compared with other polar groups once investigated (σ_(max),25℃=8.5×10^(-5) S/cm). The structure-ion conduction relation in the polymer-salt matrix is also analyzed macroscopically through the correspondence between composition-dependences of polymerization conversion and isothermal ion conductivity, and microscopically through the measurements of cross polarized light and electron transmission.展开更多
Marine biofouling is an urgent global problem in the process of ocean exploitation and utilization.In our work,a series of zinc-based acrylate copolymers(ACZn-x)were designed and synthesized using benzoic acid,zinc ox...Marine biofouling is an urgent global problem in the process of ocean exploitation and utilization.In our work,a series of zinc-based acrylate copolymers(ACZn-x)were designed and synthesized using benzoic acid,zinc oxide(ZnO)and a random quaternion copolymer consisting of ethyl acrylate(EA),butyl acrylate(BA),acrylic acid(AA)and methacrylic acid(MAA)by free radical polymerization and dehydration condensation.The ACZn-x with a zinc benzoate side chain is able to hydrolyze in natural seawater under static conditions,resulting in the formation of a smooth surface.We investigated and confirmed the antifouling(AF)behavior of ACZn-x in the laboratory and revealed that they have better antibacterial(86%for S.aureus and 72%for E.coli)and anti-algal(≥60.1%for N.closterium and≥67.5%for P.subcordiformis)activities.We also assessed the marine AF properties of ACZn-x and corresponding coatings in Qingdao,China;the ACZn-x exhibited ideal AF properties with little silt and biological mucosa adhered to the ACZn-x surface after 6 months,and corresponding coatings exhibited little biofouling after 16 months in the ocean.Importantly,possible AF mechanisms were further proposed at the cellular level.These results could be helpful for the development and application of effective AF coatings.展开更多
Olefin solution polymerization can be used to obtain high-performance polyolefin materials that cannot be obtained via other polymerization processes.Polyolefin elastomers(POE)are a typical example.Due to cost,only a ...Olefin solution polymerization can be used to obtain high-performance polyolefin materials that cannot be obtained via other polymerization processes.Polyolefin elastomers(POE)are a typical example.Due to cost,only a few linear a-olefins(e.g.,1-butene,1-hexene,and 1-octene)are used as comonomers in solution polymerization in industry.However,a-olefin comonomers with other structures may have different effects on polymerization in comparison with common linear ones.Moreover,the properties of the corresponding materials may differ significantly.In this work,copolymers of ethylene with linear and endcyclized a-olefins are synthesized using a metallocene catalyst.The copolymerization of ethylene with linear a-olefins results in a higher turn-over frequency(TOF)and lower incorporation than copolymerization with end-cyclized a-olefins,which may indicate that end-cyclized a-olefins have a higher coordination probability and lower insertion rate.In this reaction,the comonomer is distributed randomly in the polymer chain and efficiently destroys crystallization.End-cyclized a-olefins exhibit a much stronger crystallization destructive capacity(CDC)in the copolymer than linear a-olefins,possibly because linear a-olefins act mainly in the radial direction of the main chain of the polymer,while end-cyclized a-olefins act mainly in the axial direction of the main chain.展开更多
基金supported by the National Natural Science Foundation of China(Project Nos.51774062 and 52274032)Scientific and Technological Key Research Program of Chongqing Municipal Education Commission(KJZD-K201901502)+1 种基金General Project of Chongqing Natural Science Foundation(CSTB2022NSCQMSX0349)Science and Technology Research Program of Chongqing Municipal Education Commission(KJQN202313101)。
文摘Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide materials.Two new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),respectively.The structures of the drag reduction agents were confirmed by IR and1H NMR spectroscopies.The molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/mol.When the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/mol.When the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,respectively.Compared with HPAM,both of the above copolymers presented better drag reduction capacities.
基金financially supported by a grant provided by Mitsubishi Heavy Industries。
文摘Polypropylene is commonly used as a binder for ceramic injection molding,and rapid cooling is often encountered during processing.However,the crystallization behavior of polypropylene shows a strong dependence on cooling rate due to its semi-crystalline characteristics.Therefore,the influence of cooling rate on the quality of final product cannot be ignored.In this study,the fast differential scanning calorimetry(FSC)test was performed to study the influence of cooling rate on the non-isothermal crystallization behavior and non-isothermal crystallization kinetics of a copolymer polypropylene(PP BC03B).The results show that the crystallization temperatures and crystallinity decrease as the cooling rate increases.In addition,two exothermic peaks occur when cooling rate ranges from 30 to 300 K·s^(-1),indicating the formation of another crystal phase.Avrami,Ozawa and Mo equations were used to explore the non-isothermal crystallization kinetics,and it can be concluded that the Mo method is suitable for this study.
文摘Polymer science encompasses a different range of materials critical to industries spanning from packaging to biomedicine. Understanding the synthesis, characterization, and applications of common homopolymers and copolymers is fundamental to advancing polymer research and development. In this comprehensive review, we explore various preparation methods, including free radical, anionic, and cationic polymerization, utilized for synthesizing homopolymers and copolymers. Furthermore, we investigate solvent choices commonly employed for polymer characterization, ranging from neat conditions, polar protic and polar aprotic solvents. We also explored characterization techniques, including Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA). In addition to industrial applications, we highlight the diverse biological applications of homopolymers, poly(2-hydroxyethyl methacrylate) (pHEMA) and polystyrene, which find its extensive use in biomedicine. By synthesizing and analyzing this wealth of information, this review aims to provide a comprehensive understanding of the synthesis, characterization, and applications of homopolymers and copolymers, with a particular focus on their biological applications. This holistic approach not only contributes to advancements in polymer science and technology but also fosters innovation in biomedicine, ultimately benefiting human health and well-being.
基金Supported by the Basic Research Program of the State Key Laboratory of Heavy Oil Processing (200310) China University of Petroleum,Beijing,China
文摘Synthesis of a cold flow improver （MAVA-a） for diesel fuel and its effect on solidifying point （SP） and cold filter plugging point （CFPP） of diesel fuels were investigated, The cold flow improver was prepared by using maleic anhydride （MA） and vinyl acetate （VA） as raw materials, toluene as solvent, dibenzoyl peroxide （BPO） as initiator, through alternating polymerization under nitrogen to obtain a binary-polymer and then through aminolysis by using a higher carbon amine as aminating agent at a temperature of 80 ℃. A cold flow improver was designed and prepared for No. 0 diesel fuel from Zhang Jia-Gang Petrochemical Company according to the contents of n-paraffin and its carbon number distribution in the No. 0 diesel fuel. It was also used together with two kinds of ethene-vinyl acetate copolymer improvers （EVA） separately. The test result showed that the CFPP of the No. 0 diesel fuel could be lowered by 3-5 ℃ when the improver MAVA-a was used. The CFPP was lowered by 8℃ when the improver MAVA-a was used together with EVA-2.
基金Funded by the Natural Science Foundation of Liaoning Province of China(No.20180550432)Natural Science Foundation for Young Doctoral Research(No.2020-BS-158)Basic Scientific Research Project of Colleges and Universities of Liaoning Provincial Department of Education(No.LJKQZ2021060)。
文摘A novel polypropylene random(PPR)composite materials with optimized properties was developed by addingβ-nucleating compound agents(rare earth complex WBG-2 and aryl amide derivative TMB-5)and ternary compound modifier(TPE/WBG-2/CaCO_(3)).The effects of differentβ-nucleating agents and ternary compound modifier on the mechanical properties and crystallization behavior of PPR were analyzed.The results show that,compared with pure PPR materials,both WBG-2 and TMB-5 could significantly improve the impact strength of PPR.The crystallization temperature of PPR increased with the addition ofβ-nucleating agent.The modified PPR prepared with ternary compound modifier showed the most excellent comprehensive properties.
基金financial support from the projects of the National Natural Science Foundation of China (52373074 and 51972121)the Independent Research Project of Maoming Laboratory (2022ZD002)。
文摘Solid-state lithium(Li) metal batteries overwhelm the lithium-ion batteries by harvesting high energy from Li metal anode with ultrahigh capacities and gaining excellent safety from solid electrolytes.However,the uncontrollable solvents in solid electrolytes usually aggravate poor interfacial contact with lithium metal anode and deteriorate Li^(+) pathways.Here a copolymeric network-structured ion conductor by rationally integrating cellulose nanofibril as a two-in-one functional material is employed to anchor the solvent.Taking advantages of tightly anchoring of cellulose nanofibril to solvent,the asconstructed quasi-solid polymer-based electrolyte offers rapid Li^(+) transport channels and realizes effective Li-dendrite suppression,which enables high ionic conductivity of 1.93 × 10^(-3)S cm^(-1) at room temperature,long-term Li plating/stripping over 1900 h,and high capacity retention of 99%.This work provides a fresh strategy for creating solid electrolytes that meet both high ionic conductivity and interfacial stability requirements for practical solid-state lithium metal battery.
文摘Ringlike polar monomer maleic, anhydride (MAn) was copolymerized with oligo (oxyethylene) methacrylate (MEO_n), and its effect on ion conduction property of the corresponding polymer-salt complexes was studied. As a consequence the introduction of MAn onto polymer chain retards crystallization of the ether pendants considerably, and improves the ion conductivity to a larger degree compared with other polar groups once investigated (σ_(max),25℃=8.5×10^(-5) S/cm). The structure-ion conduction relation in the polymer-salt matrix is also analyzed macroscopically through the correspondence between composition-dependences of polymerization conversion and isothermal ion conductivity, and microscopically through the measurements of cross polarized light and electron transmission.
基金supported by the National Key Research and Development Project(No.2019YFC0312101)the Scientific Research Project of Sanya Yazhou Bay Science and Technology City Administration(No.SKJC2020-01-015)the Hainan Provincial Key Research and Development Project(No.ZDYF2021GXJS029)。
文摘Marine biofouling is an urgent global problem in the process of ocean exploitation and utilization.In our work,a series of zinc-based acrylate copolymers(ACZn-x)were designed and synthesized using benzoic acid,zinc oxide(ZnO)and a random quaternion copolymer consisting of ethyl acrylate(EA),butyl acrylate(BA),acrylic acid(AA)and methacrylic acid(MAA)by free radical polymerization and dehydration condensation.The ACZn-x with a zinc benzoate side chain is able to hydrolyze in natural seawater under static conditions,resulting in the formation of a smooth surface.We investigated and confirmed the antifouling(AF)behavior of ACZn-x in the laboratory and revealed that they have better antibacterial(86%for S.aureus and 72%for E.coli)and anti-algal(≥60.1%for N.closterium and≥67.5%for P.subcordiformis)activities.We also assessed the marine AF properties of ACZn-x and corresponding coatings in Qingdao,China;the ACZn-x exhibited ideal AF properties with little silt and biological mucosa adhered to the ACZn-x surface after 6 months,and corresponding coatings exhibited little biofouling after 16 months in the ocean.Importantly,possible AF mechanisms were further proposed at the cellular level.These results could be helpful for the development and application of effective AF coatings.
文摘Olefin solution polymerization can be used to obtain high-performance polyolefin materials that cannot be obtained via other polymerization processes.Polyolefin elastomers(POE)are a typical example.Due to cost,only a few linear a-olefins(e.g.,1-butene,1-hexene,and 1-octene)are used as comonomers in solution polymerization in industry.However,a-olefin comonomers with other structures may have different effects on polymerization in comparison with common linear ones.Moreover,the properties of the corresponding materials may differ significantly.In this work,copolymers of ethylene with linear and endcyclized a-olefins are synthesized using a metallocene catalyst.The copolymerization of ethylene with linear a-olefins results in a higher turn-over frequency(TOF)and lower incorporation than copolymerization with end-cyclized a-olefins,which may indicate that end-cyclized a-olefins have a higher coordination probability and lower insertion rate.In this reaction,the comonomer is distributed randomly in the polymer chain and efficiently destroys crystallization.End-cyclized a-olefins exhibit a much stronger crystallization destructive capacity(CDC)in the copolymer than linear a-olefins,possibly because linear a-olefins act mainly in the radial direction of the main chain of the polymer,while end-cyclized a-olefins act mainly in the axial direction of the main chain.
