Anion-exchange membranes(AEMs)with high conductivity and stability are essential components of hydrogen related water electrolysis and fuel cell applications.During the past decades,polynorbornene(PNB)-based AEMs have...Anion-exchange membranes(AEMs)with high conductivity and stability are essential components of hydrogen related water electrolysis and fuel cell applications.During the past decades,polynorbornene(PNB)-based AEMs have shown excellent performance due to their saturated all-carbon-based backbones and diverse strategies to prepare cross-linked membranes.However,nearly all previously reported PNB-based AEMs rely on the alkyl-substituted norbornene monomers,whose low-yielding synthesis leads to high-cost of the AEMs.In addition,the crosslinked PNB-based AEMs usually suffered from mechanical brittleness.Herein,we propose a novel semi-interpenetrating polymer network(s-IPN)strategy to simultaneously enhance mechanical modulus and ionic conductivity,while using commercial 5-vinyl-2-norbornene(VNB)as the single norbornene derivatives to prepare high-performance AEMs.A diallylphenol quaternary ammonium salt was used for photo-induced crosslinking with poly-VNB and various dithiols to produce AEMs with s-IPN structures.The resultant membranes have excellent hydroxide conductivities and alkaline stability in 1 mol/L KOH at 80℃,and are successfully applied in alkaline anion-exchange membrane water electrolyzers to stably operateforover150h.展开更多
An efficient and regioselective synthesis of N-9 alkoxyalkylated purine nucleoside derivatives was achieved via the N-alkoxyalkylation of purine rings with vinyl ethers catalyzed by L-ProT.The advantages of this proto...An efficient and regioselective synthesis of N-9 alkoxyalkylated purine nucleoside derivatives was achieved via the N-alkoxyalkylation of purine rings with vinyl ethers catalyzed by L-ProT.The advantages of this protocol include good to excellent yield,mild reaction condition,and simple manipulation.A plausible mechanism for the transformation was given.展开更多
合成了3种5,5′-亚甲基-双-水杨醛亚胺配体,利用它们和trans-[NiCl(Ph)(PPh3)2]反应得到Cat1、Cat2和Cat3三种双核水杨醛亚胺镍催化剂,并通过红外(FT-IR)和元素分析进行了表征。研究了在甲苯为溶剂,MAO为助催化剂下,催化降冰片烯(NBE)...合成了3种5,5′-亚甲基-双-水杨醛亚胺配体,利用它们和trans-[NiCl(Ph)(PPh3)2]反应得到Cat1、Cat2和Cat3三种双核水杨醛亚胺镍催化剂,并通过红外(FT-IR)和元素分析进行了表征。研究了在甲苯为溶剂,MAO为助催化剂下,催化降冰片烯(NBE)单体聚合的催化性能,考察了聚合条件,如温度、Al/Ni物质的量比对降冰片烯的催化活性、单体转化率、聚合物分子量及分子量分布的影响。当在n(Al)/n(Ni)为1000,聚合温度为80℃的条件下,催化剂的催化活性达到最大值1.16×105g of PNB/(mol of Ni.h)。聚合产物的核磁共振(1H-NMR)和红外光谱分析结果表明,该聚合反应是以单体的乙烯基加成聚合机理进行的。展开更多
Polynorbornenes were synthesized in the presence of an iron based catalyst, 2,6-bis[1-(2,6-diisopropyl-phenylimino)ethyl]pyridine iron(Ⅱ) dichloride. The FTIR, 1H NMR and 13C NMR analysis results revealed t...Polynorbornenes were synthesized in the presence of an iron based catalyst, 2,6-bis[1-(2,6-diisopropyl-phenylimino)ethyl]pyridine iron(Ⅱ) dichloride. The FTIR, 1H NMR and 13C NMR analysis results revealed that the structure of the obtained polynorbornenes consisted of vinyl addition polymer substructures without any ring-opening structures. The polymers were amorphous with a short-range order, displayed in the WAXD(wide angle X-ray diffraction) diagrams. The glass transition temperatures ranged from 200 to 400 ℃. The effects of the polymerization reaction conditions, such as Al/Fe molar ratio and toluene/CH_2Cl_2 volume ratio, on the activity, intrinsic viscosity and T_g were also studied.展开更多
基金financially supported by the Ministry of Science and Technology of China under the National Key R&D Program of China (No.2023YFB3811200)the National Natural Science Foundation of China (No.22075292).
文摘Anion-exchange membranes(AEMs)with high conductivity and stability are essential components of hydrogen related water electrolysis and fuel cell applications.During the past decades,polynorbornene(PNB)-based AEMs have shown excellent performance due to their saturated all-carbon-based backbones and diverse strategies to prepare cross-linked membranes.However,nearly all previously reported PNB-based AEMs rely on the alkyl-substituted norbornene monomers,whose low-yielding synthesis leads to high-cost of the AEMs.In addition,the crosslinked PNB-based AEMs usually suffered from mechanical brittleness.Herein,we propose a novel semi-interpenetrating polymer network(s-IPN)strategy to simultaneously enhance mechanical modulus and ionic conductivity,while using commercial 5-vinyl-2-norbornene(VNB)as the single norbornene derivatives to prepare high-performance AEMs.A diallylphenol quaternary ammonium salt was used for photo-induced crosslinking with poly-VNB and various dithiols to produce AEMs with s-IPN structures.The resultant membranes have excellent hydroxide conductivities and alkaline stability in 1 mol/L KOH at 80℃,and are successfully applied in alkaline anion-exchange membrane water electrolyzers to stably operateforover150h.
基金the Natural Science Foundation of Zhejiang Province(No.LY13B020015)Zhejiang Key Innovation Team of Green Pharmaceutical Technology(No.2012R10043-07) for financial support
文摘An efficient and regioselective synthesis of N-9 alkoxyalkylated purine nucleoside derivatives was achieved via the N-alkoxyalkylation of purine rings with vinyl ethers catalyzed by L-ProT.The advantages of this protocol include good to excellent yield,mild reaction condition,and simple manipulation.A plausible mechanism for the transformation was given.
文摘合成了3种5,5′-亚甲基-双-水杨醛亚胺配体,利用它们和trans-[NiCl(Ph)(PPh3)2]反应得到Cat1、Cat2和Cat3三种双核水杨醛亚胺镍催化剂,并通过红外(FT-IR)和元素分析进行了表征。研究了在甲苯为溶剂,MAO为助催化剂下,催化降冰片烯(NBE)单体聚合的催化性能,考察了聚合条件,如温度、Al/Ni物质的量比对降冰片烯的催化活性、单体转化率、聚合物分子量及分子量分布的影响。当在n(Al)/n(Ni)为1000,聚合温度为80℃的条件下,催化剂的催化活性达到最大值1.16×105g of PNB/(mol of Ni.h)。聚合产物的核磁共振(1H-NMR)和红外光谱分析结果表明,该聚合反应是以单体的乙烯基加成聚合机理进行的。
基金Supported by the Special Funds for Major State Basic Research Projects( No.G19990 64 80 0 ),the National NaturalScience Foundation of China( No.2 973 4141) ,and SKL EP ( 0 0 62 ) ,SINOPEC and CNPC.
文摘Polynorbornenes were synthesized in the presence of an iron based catalyst, 2,6-bis[1-(2,6-diisopropyl-phenylimino)ethyl]pyridine iron(Ⅱ) dichloride. The FTIR, 1H NMR and 13C NMR analysis results revealed that the structure of the obtained polynorbornenes consisted of vinyl addition polymer substructures without any ring-opening structures. The polymers were amorphous with a short-range order, displayed in the WAXD(wide angle X-ray diffraction) diagrams. The glass transition temperatures ranged from 200 to 400 ℃. The effects of the polymerization reaction conditions, such as Al/Fe molar ratio and toluene/CH_2Cl_2 volume ratio, on the activity, intrinsic viscosity and T_g were also studied.
