Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate (BHET) were successfully synthesized and characterized by fourier transform infrared spectroscopy (FT-IR). These two k...Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate (BHET) were successfully synthesized and characterized by fourier transform infrared spectroscopy (FT-IR). These two kinds of salts were used to intercalate Na-MMT to yield two kinds of respective organo-modified MMTs. Basal spacing and thermal stability were investigated by using X-ray diffraction (XRD) and thermogravimetric analysis (TGA), respectively. The experimental results show that, as compared with Na-MMT, basal spacings of both of MMTs modified by the quaternary phosphonium salt of BHET (BHETPP) and the quaternary ammonium salt of BHET (BHEA), increase from 12.4 A to 19.7/k and 31.3 A, respec-tively. Thermal stability of BHETPP-modified MMT is much better than that of BHEA-modified MMT, i e, T otof BHETPP-modified MMT is around 400℃ while Tcmset of BHEA-modified MMT is near 250℃. Therefore, with en-larged basal spacing and excellent thermal stability, BHETPP-modified MMT is a promising organo-modified MMT which may be used to prepare polyethylene terephthalate/MMT nanocomposite with high thermal and mechanical performance.展开更多
The aim of this research is to develop a novel non-leaching antimicrobial waterborne polyurethane(WPU)leather coating material with covalently attached quaternary phosphonium salt(QPS).The structure of the QPS-bearing...The aim of this research is to develop a novel non-leaching antimicrobial waterborne polyurethane(WPU)leather coating material with covalently attached quaternary phosphonium salt(QPS).The structure of the QPS-bearing WPU has been identified,and their thermal stability,mechanical property,and antimicrobial performance have been investigated.The results reveal that the incorporation of QPS slightly reduces the thermal stability of WPU material but would not affects its usability as leather coating.Despite the presence of hydrophobic benzene in QPS structure,the strong hydration of its cationic groups leads to the increased surface contact angle(SCA)and water absorption rate(WAR)of the films,suggesting that the water resistance of the films needs to be improved for the purpose of leather coatings.Antibacterial tests demonstrate that when the QPS content is 20 wt%,QPS-bearing WPU shows effective antimicrobial activity against bacteria.The WPU containing QPS prepared in this study is a non-leaching antimicrobial material and has great potential application as leather coating.展开更多
Currently,it encounters great challenges to accomplish catalyzing various kinds of carbon dioxide(CO_(2))conversion reactions efficiently with single catalyst,let alone control the interplay among catalytic efficiency...Currently,it encounters great challenges to accomplish catalyzing various kinds of carbon dioxide(CO_(2))conversion reactions efficiently with single catalyst,let alone control the interplay among catalytic efficiency and selectivity evenly.Here,we prepared a functional covalent organic framework,[PTPP]X%-TD-COF[PTPP=3-bromopropyltriphenylphosphonium;TD=1,3,5-tri(4-aminophenyl)benzene-1,4-diformylbenzene],by immobilizing the quaternary phosphonium salt onto the skeleton of COFs through a post-synthesis strategy for versatilely catalyzing reduction of CO_(2) and CO_(2) fixation on epoxide and aziridine facilely.With the typical features of COFs(such as porosity and ordered structure)and catalytic activity of the quaternary phosphonium salt,[PTPP]X%-TD-COF possesses an intensely synergistic effect for catalyzing the chemical transformations of CO_(2).Noteworthily,the quaternary phosphonium salt functionalized COFs catalyze the CO_(2) reduction reaction with amine and phenylsilane to produce formylated and methylated products under gentle reaction conditions with high selectivity and efficiency.Furthermore,[PTPP]_(X%)-TD-COF shows high catalytic ability in CO_(2) chemical fixation reactions.展开更多
Two novel coordination compounds of Zn(Ⅱ) with Ph_3P+(CH_2)_2CO-_2(L), namely, [ZnL_4(H_2O)_2]·(ClO_4)_2·2H_2O(compound 1) and [Zn_2Cl_4(μ-L-O,O′)_2](compound 2), have been prepared. The single crystal X-...Two novel coordination compounds of Zn(Ⅱ) with Ph_3P+(CH_2)_2CO-_2(L), namely, [ZnL_4(H_2O)_2]·(ClO_4)_2·2H_2O(compound 1) and [Zn_2Cl_4(μ-L-O,O′)_2](compound 2), have been prepared. The single crystal X-ray structure analysis of these compounds indicates that in compound 1 the Zn(Ⅱ) atom is coordinated by four monodentate carboxylato groups on the equatorial plane and two aqua ligands occupy the axial coordination positions. The pendant oxygen atoms form strong hydrogen bonds with the aqua molecules which results in the stability of this structure. In compound 2, two Zn(Ⅱ) atoms are bridged by a pair of carboxylato groups, showing a skew-bridge mode, and thus enabling a long Zn(Ⅱ)…Zn(Ⅱ) separation. As we know, it is a dinuclear coordination compound with the longest Zn…Zn separation.展开更多
文摘Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate (BHET) were successfully synthesized and characterized by fourier transform infrared spectroscopy (FT-IR). These two kinds of salts were used to intercalate Na-MMT to yield two kinds of respective organo-modified MMTs. Basal spacing and thermal stability were investigated by using X-ray diffraction (XRD) and thermogravimetric analysis (TGA), respectively. The experimental results show that, as compared with Na-MMT, basal spacings of both of MMTs modified by the quaternary phosphonium salt of BHET (BHETPP) and the quaternary ammonium salt of BHET (BHEA), increase from 12.4 A to 19.7/k and 31.3 A, respec-tively. Thermal stability of BHETPP-modified MMT is much better than that of BHEA-modified MMT, i e, T otof BHETPP-modified MMT is around 400℃ while Tcmset of BHEA-modified MMT is near 250℃. Therefore, with en-larged basal spacing and excellent thermal stability, BHETPP-modified MMT is a promising organo-modified MMT which may be used to prepare polyethylene terephthalate/MMT nanocomposite with high thermal and mechanical performance.
基金Innovation Team Program of Science and Technology(2017TD0010)Key research and development project(2018GZ031518)of Sichuan Province+1 种基金China Postdoctoral Science Foundation(2018 M631083,2019 T120842)postdoctoral research and development Foundation of Sichuan University(2019SCU12060)are gratefully acknowledged.
文摘The aim of this research is to develop a novel non-leaching antimicrobial waterborne polyurethane(WPU)leather coating material with covalently attached quaternary phosphonium salt(QPS).The structure of the QPS-bearing WPU has been identified,and their thermal stability,mechanical property,and antimicrobial performance have been investigated.The results reveal that the incorporation of QPS slightly reduces the thermal stability of WPU material but would not affects its usability as leather coating.Despite the presence of hydrophobic benzene in QPS structure,the strong hydration of its cationic groups leads to the increased surface contact angle(SCA)and water absorption rate(WAR)of the films,suggesting that the water resistance of the films needs to be improved for the purpose of leather coatings.Antibacterial tests demonstrate that when the QPS content is 20 wt%,QPS-bearing WPU shows effective antimicrobial activity against bacteria.The WPU containing QPS prepared in this study is a non-leaching antimicrobial material and has great potential application as leather coating.
基金supported by the National Natural Science Foundation of China(Nos.22075060,21911530146)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000).
文摘Currently,it encounters great challenges to accomplish catalyzing various kinds of carbon dioxide(CO_(2))conversion reactions efficiently with single catalyst,let alone control the interplay among catalytic efficiency and selectivity evenly.Here,we prepared a functional covalent organic framework,[PTPP]X%-TD-COF[PTPP=3-bromopropyltriphenylphosphonium;TD=1,3,5-tri(4-aminophenyl)benzene-1,4-diformylbenzene],by immobilizing the quaternary phosphonium salt onto the skeleton of COFs through a post-synthesis strategy for versatilely catalyzing reduction of CO_(2) and CO_(2) fixation on epoxide and aziridine facilely.With the typical features of COFs(such as porosity and ordered structure)and catalytic activity of the quaternary phosphonium salt,[PTPP]X%-TD-COF possesses an intensely synergistic effect for catalyzing the chemical transformations of CO_(2).Noteworthily,the quaternary phosphonium salt functionalized COFs catalyze the CO_(2) reduction reaction with amine and phenylsilane to produce formylated and methylated products under gentle reaction conditions with high selectivity and efficiency.Furthermore,[PTPP]_(X%)-TD-COF shows high catalytic ability in CO_(2) chemical fixation reactions.
文摘Two novel coordination compounds of Zn(Ⅱ) with Ph_3P+(CH_2)_2CO-_2(L), namely, [ZnL_4(H_2O)_2]·(ClO_4)_2·2H_2O(compound 1) and [Zn_2Cl_4(μ-L-O,O′)_2](compound 2), have been prepared. The single crystal X-ray structure analysis of these compounds indicates that in compound 1 the Zn(Ⅱ) atom is coordinated by four monodentate carboxylato groups on the equatorial plane and two aqua ligands occupy the axial coordination positions. The pendant oxygen atoms form strong hydrogen bonds with the aqua molecules which results in the stability of this structure. In compound 2, two Zn(Ⅱ) atoms are bridged by a pair of carboxylato groups, showing a skew-bridge mode, and thus enabling a long Zn(Ⅱ)…Zn(Ⅱ) separation. As we know, it is a dinuclear coordination compound with the longest Zn…Zn separation.