The photoconductive characteristic of the inorganic/organic hybridized polymer system is reported, in which a novel bi-functional photorefractive (PR) poly(N-vinyl)-3-[p-nitrophenylazo]carbazole (PVNPAK) serves as a p...The photoconductive characteristic of the inorganic/organic hybridized polymer system is reported, in which a novel bi-functional photorefractive (PR) poly(N-vinyl)-3-[p-nitrophenylazo]carbazole (PVNPAK) serves as a polymeric charge-transporting and second-order nonliner optical matrix and quantum dots composed of surface passivated cadmium sulfide serve as a charge-generation sensitizer. The hybrid PVNPAK/CdS-nanoparticles polymer composites with different mass ratio of CdS to PVNPAK were prepared. The generation of photocurrent on illumination and photoconductive properties of the PVNPAK/CdS-nanoparticles polymer composites were studied. The results show that the addition of CdS nanoparticle as a photosensitizer can enhance the photoconductivity of the PVNPAK significantly because of the properties of the high quantum efficiency of photosensitization and high charge transport to conducting polymer.展开更多
The fullerene C-60 and phthatocyanine co-grafted poly (epoxy propyl carbazole) (C-60-CuPC-PEPC) was synthesized by Friedel-Crafts reaction. It was found that C-60-CuPc-PEPC had good UV-Vis absorption property, whose a...The fullerene C-60 and phthatocyanine co-grafted poly (epoxy propyl carbazole) (C-60-CuPC-PEPC) was synthesized by Friedel-Crafts reaction. It was found that C-60-CuPc-PEPC had good UV-Vis absorption property, whose active spectral range was expanded from UV to visible spectrum region, and exhibited better photoconductivity than CuPc-PEPC and PEPC. These improvements could be attributed to the interaction between C-60, phthalocyanine and PEPC.展开更多
The molecular structures of 135 poly-bromine carbazole (PBCZs) compounds were fully optimized at the B3LYP/6-31G* level, and their thermodynamic properties at 98.15 K, 1.013 ×105 Pa were consequently obtained....The molecular structures of 135 poly-bromine carbazole (PBCZs) compounds were fully optimized at the B3LYP/6-31G* level, and their thermodynamic properties at 98.15 K, 1.013 ×105 Pa were consequently obtained. Based on our isodesmic reaction, standard formation heat (ΔfHθ) and standard formation free energy (ΔfGθ) of PBCZs were calculated. Furthermore, the relationship between thermodynamic parameters and the position and number (NPBS) of Brsubstitution were also discussed. To our interest, a good dependence can be observed among entro- py (Sθ), ΔfHθ, ΔfGθ and NPBS. Ultimately, the theoretical stability order of isomers can be decided judging from the ΔfGθ value.展开更多
The optical properties of the fullerenated poly(epoxy propyl carbazole) (PEPC) have been investigated. Compared with pure PEPC, fullerenated PEPC has the same structure in the UV region of the absorption spectrum, and...The optical properties of the fullerenated poly(epoxy propyl carbazole) (PEPC) have been investigated. Compared with pure PEPC, fullerenated PEPC has the same structure in the UV region of the absorption spectrum, and extends the active range to a longer wavelength. The apparent quenching of PEPC fluorescence was observed in the fullerenated polymer and it can be attributed to intramolecular excited state energy transfer.展开更多
Conventional self-assembled monolayer(SAM)hole transporters in organic solar cells(OSCs)generally suffer from poor uniformity and limited thickness tolerance,hindering their large-scale production.To overcome these li...Conventional self-assembled monolayer(SAM)hole transporters in organic solar cells(OSCs)generally suffer from poor uniformity and limited thickness tolerance,hindering their large-scale production.To overcome these limitations,we introduce a novel polymeric hole transporter synthesized by polymerizing carbazole phosphonic acid(PACz).The resultant Poly-2PACz material exhibits exceptional conductivity,high tolerance for variations in layer thickness,and improved film uniformity compared with conventional SAMs.Consequently,the OSCs utilizing Poly-2PACz achieve a remarkable power conversion efficiency of 19.1%and a high fill factor of 81.2%,surpassing the devices based on 2PACz.Moreover,Poly-2PACz-based OSCs demonstrate excellent operational stability,retaining over 80%of their initial efficiency after 1,400 h of continuous light exposure in ambient conditions.This work presents a novel strategy for designing hole transporters,paving the way for more efficient and stable OSCs.展开更多
Low dosage kinetic hydrate inhibitors(KHIs)are a kind of alternative chemical additives to high dosage thermodynamic inhibitors for preventing gas hydrate formation in oil&gas production wells and transportation p...Low dosage kinetic hydrate inhibitors(KHIs)are a kind of alternative chemical additives to high dosage thermodynamic inhibitors for preventing gas hydrate formation in oil&gas production wells and transportation pipelines.In this paper,a new KHI,poly(N-vinyl caprolactam)-co-tert-butyl acrylate(PVCapco-TBA),was successfully synthesized with N-vinyl caprolactam(NVCap)and tert-butyl acrylate.The kinetic inhibition performances of PVCap-co-TBA on the formations of both structureⅠmethane hydrate and structureⅡnatural gas hydrate were investigated by measuring the onset times of hydrate formation under different conditions and compared with commercial KHIs such as PVP,PVCap and inhibex 501.The results indicated that PVCap-co-TBA outperformed these widely applied inhibitors for both structureⅠand structureⅡhydrates.At the same dosage of KHI,the maximum tolerable degree of subcooling under which the onset time of hydrate formation exceeded 24 hours for structureⅠhydrate was much lower than that for structureⅡhydrate.The inhibition strength increased with the increasing dosage of PVCap-co-TBA;The maximum tolerable degree of subcooling for the natural gas hydrate is more than10 K when the dosage was higher than 0.5%(mass)while it achieved 12 K when that dosage rose to0.75%(mass).Additionally,we found polypropylene glycol could be used as synergist at the dosage of 1.0%(mass)or so,under which the kinetic inhibition performance of PVCap-co-TBA could be improved significantly.All evaluation results demonstrated that PVCap-co-TBA was a very promising KHI and a competitive alternative to the existing commercial KHIs.展开更多
Poly(propylene fumarate-co-propylene sebacate) (P(PF-co-PS)) was crosslinked with Nvinyl pyrrolidone (N-VP) to form networks. It was investigated as biodegradable bone cement. In this paper, P(PF-co-PS) was ...Poly(propylene fumarate-co-propylene sebacate) (P(PF-co-PS)) was crosslinked with Nvinyl pyrrolidone (N-VP) to form networks. It was investigated as biodegradable bone cement. In this paper, P(PF-co-PS) was synthesized and characterized by ^1H-NMR, FTIR and GPC. The effects of the amount of sebacate segments in P(PF-co-PS) main chains and the quantity of N-vinyl pyrrolidone on the in vitro degradation of the polymer networks were examined. Cylindrical specimens were submerged in phosphate buffered saline (PBS) at 37 ℃ and the pH value of PBS is 7.4 for 10 weeks. The gravimetry and compressive mechanical properties were tested over the degradation period. Networks formed by P(PF-oo-PS)8020/N-VP exhibited higher weight loss and better mechanical properties when compared with poly(propylene fumarate)/N-VP networks. The mechanical properties of P(PF-co-PS)/N-VP can be maintained for a very long time, even for 70 days, the yield strength, fracture strength and compressive modulus are (51.78 ± 2.01) MPa, (52.331 ± 1.84) MPa and (957.78 ± 24.40) MPa, respectively. The results demonstrate that the compressive mechanical properties and degradation velocity can be modulated by the amount of crosslinking agents and sebacate segments along the main chains of copolymers.展开更多
We have analyzed the photorefractive(PR) effect of a polymer composite was reported which combines a novel bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl(PVNPAK) and 2,4,7-trinitro-9-fluorenone(TNF...We have analyzed the photorefractive(PR) effect of a polymer composite was reported which combines a novel bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl(PVNPAK) and 2,4,7-trinitro-9-fluorenone(TNF). PVNPAK was synthesized by a post-azo-coupling reaction, with an azo derivative as the electrooptic chromophore and carbazolyl as photoconductive moiety. The asymmetric two-beam coupling gain of 13.9 cm-1 and diffraction efficiency of 1.2% for poled polymer film fabricated using a corona poling are obtained at the wavelength of 647.1 nm, confirming photorefractivity. We interpreted this result as the orientational enhancement, in which the spatial charge field may enhance the modulated orientation of the azobenzen chromophore. It is unexpected that the photorefractive gain of 9.5 cm-1 for the unpoled polymer film also was observed without external field in two-beam coupling(TBC) experiment. This phenomenon is attributed to a light-induced orientational grating when the azobenzene groups are illuminated by polarized light.展开更多
The C60 grafted poly(N-vinyl carbazole) (PVK) polymer(CGP) was prepared by simple radical polymerization initiated by BPO at 90℃.The products were characterized by UV-Vis, FTIR, GPC and fluorescence and it was proven...The C60 grafted poly(N-vinyl carbazole) (PVK) polymer(CGP) was prepared by simple radical polymerization initiated by BPO at 90℃.The products were characterized by UV-Vis, FTIR, GPC and fluorescence and it was proven that C60 was grafted covalently to the PVK. The C60 moiety in the product was about 1. 2% (mass fraction). The photoconductlvity study revealed that the photoconductivity of PVK was improved obviously through grafting C60.The half time of light decaying (t1/2) of CGP reached 0. 35 s.展开更多
PVK or PVK-C60 solution was dropped onto the alumina membrane and the solution was filled into the channel of the membrane due to the capillary action. As the solvent evaporation, the nanotubes were formed. The morpho...PVK or PVK-C60 solution was dropped onto the alumina membrane and the solution was filled into the channel of the membrane due to the capillary action. As the solvent evaporation, the nanotubes were formed. The morphology of the sample was examined by SEM and fluorescence of PVK and PVK-C60 was determined. Emis- sion intensity of PVK was weakened by C60, indicating that C60 improved the conductive property of PVK nan- otubes.展开更多
基金Project(60537050) supported by the National Nature Science Foundation of China Project supported by the Opening Fund of Key Laboratory of Nonferrous Materials and Processing Technology.
文摘The photoconductive characteristic of the inorganic/organic hybridized polymer system is reported, in which a novel bi-functional photorefractive (PR) poly(N-vinyl)-3-[p-nitrophenylazo]carbazole (PVNPAK) serves as a polymeric charge-transporting and second-order nonliner optical matrix and quantum dots composed of surface passivated cadmium sulfide serve as a charge-generation sensitizer. The hybrid PVNPAK/CdS-nanoparticles polymer composites with different mass ratio of CdS to PVNPAK were prepared. The generation of photocurrent on illumination and photoconductive properties of the PVNPAK/CdS-nanoparticles polymer composites were studied. The results show that the addition of CdS nanoparticle as a photosensitizer can enhance the photoconductivity of the PVNPAK significantly because of the properties of the high quantum efficiency of photosensitization and high charge transport to conducting polymer.
文摘The fullerene C-60 and phthatocyanine co-grafted poly (epoxy propyl carbazole) (C-60-CuPC-PEPC) was synthesized by Friedel-Crafts reaction. It was found that C-60-CuPc-PEPC had good UV-Vis absorption property, whose active spectral range was expanded from UV to visible spectrum region, and exhibited better photoconductivity than CuPc-PEPC and PEPC. These improvements could be attributed to the interaction between C-60, phthalocyanine and PEPC.
基金Supported by the NNSFC (20977046, 20737001)NSF of Zhejiang Province (2008Y507280)
文摘The molecular structures of 135 poly-bromine carbazole (PBCZs) compounds were fully optimized at the B3LYP/6-31G* level, and their thermodynamic properties at 98.15 K, 1.013 ×105 Pa were consequently obtained. Based on our isodesmic reaction, standard formation heat (ΔfHθ) and standard formation free energy (ΔfGθ) of PBCZs were calculated. Furthermore, the relationship between thermodynamic parameters and the position and number (NPBS) of Brsubstitution were also discussed. To our interest, a good dependence can be observed among entro- py (Sθ), ΔfHθ, ΔfGθ and NPBS. Ultimately, the theoretical stability order of isomers can be decided judging from the ΔfGθ value.
文摘The optical properties of the fullerenated poly(epoxy propyl carbazole) (PEPC) have been investigated. Compared with pure PEPC, fullerenated PEPC has the same structure in the UV region of the absorption spectrum, and extends the active range to a longer wavelength. The apparent quenching of PEPC fluorescence was observed in the fullerenated polymer and it can be attributed to intramolecular excited state energy transfer.
基金supported by the National Natural Science Foundation of China(52372196)the Natural Science Foundation of Jiangsu Province(BK20230794)Jiangsu Association for Science and Technology(TJ-2022-056)。
文摘Conventional self-assembled monolayer(SAM)hole transporters in organic solar cells(OSCs)generally suffer from poor uniformity and limited thickness tolerance,hindering their large-scale production.To overcome these limitations,we introduce a novel polymeric hole transporter synthesized by polymerizing carbazole phosphonic acid(PACz).The resultant Poly-2PACz material exhibits exceptional conductivity,high tolerance for variations in layer thickness,and improved film uniformity compared with conventional SAMs.Consequently,the OSCs utilizing Poly-2PACz achieve a remarkable power conversion efficiency of 19.1%and a high fill factor of 81.2%,surpassing the devices based on 2PACz.Moreover,Poly-2PACz-based OSCs demonstrate excellent operational stability,retaining over 80%of their initial efficiency after 1,400 h of continuous light exposure in ambient conditions.This work presents a novel strategy for designing hole transporters,paving the way for more efficient and stable OSCs.
基金supported by the National Natural Science Foundation of China(U20B6005)Hainan Province Science and Technology Special Fund(ZDKJ2021026)。
文摘Low dosage kinetic hydrate inhibitors(KHIs)are a kind of alternative chemical additives to high dosage thermodynamic inhibitors for preventing gas hydrate formation in oil&gas production wells and transportation pipelines.In this paper,a new KHI,poly(N-vinyl caprolactam)-co-tert-butyl acrylate(PVCapco-TBA),was successfully synthesized with N-vinyl caprolactam(NVCap)and tert-butyl acrylate.The kinetic inhibition performances of PVCap-co-TBA on the formations of both structureⅠmethane hydrate and structureⅡnatural gas hydrate were investigated by measuring the onset times of hydrate formation under different conditions and compared with commercial KHIs such as PVP,PVCap and inhibex 501.The results indicated that PVCap-co-TBA outperformed these widely applied inhibitors for both structureⅠand structureⅡhydrates.At the same dosage of KHI,the maximum tolerable degree of subcooling under which the onset time of hydrate formation exceeded 24 hours for structureⅠhydrate was much lower than that for structureⅡhydrate.The inhibition strength increased with the increasing dosage of PVCap-co-TBA;The maximum tolerable degree of subcooling for the natural gas hydrate is more than10 K when the dosage was higher than 0.5%(mass)while it achieved 12 K when that dosage rose to0.75%(mass).Additionally,we found polypropylene glycol could be used as synergist at the dosage of 1.0%(mass)or so,under which the kinetic inhibition performance of PVCap-co-TBA could be improved significantly.All evaluation results demonstrated that PVCap-co-TBA was a very promising KHI and a competitive alternative to the existing commercial KHIs.
基金Supported by Science Commission of Tianjin (NO.043186011)Outstanding Young Scholarship from NSFC(NO.30125043)+1 种基金the Basic Research Project(NO.2002CCA016500) of the MOSTthe Natural Science Foundation of Tianjin (NO.043803511) .
文摘Poly(propylene fumarate-co-propylene sebacate) (P(PF-co-PS)) was crosslinked with Nvinyl pyrrolidone (N-VP) to form networks. It was investigated as biodegradable bone cement. In this paper, P(PF-co-PS) was synthesized and characterized by ^1H-NMR, FTIR and GPC. The effects of the amount of sebacate segments in P(PF-co-PS) main chains and the quantity of N-vinyl pyrrolidone on the in vitro degradation of the polymer networks were examined. Cylindrical specimens were submerged in phosphate buffered saline (PBS) at 37 ℃ and the pH value of PBS is 7.4 for 10 weeks. The gravimetry and compressive mechanical properties were tested over the degradation period. Networks formed by P(PF-oo-PS)8020/N-VP exhibited higher weight loss and better mechanical properties when compared with poly(propylene fumarate)/N-VP networks. The mechanical properties of P(PF-co-PS)/N-VP can be maintained for a very long time, even for 70 days, the yield strength, fracture strength and compressive modulus are (51.78 ± 2.01) MPa, (52.331 ± 1.84) MPa and (957.78 ± 24.40) MPa, respectively. The results demonstrate that the compressive mechanical properties and degradation velocity can be modulated by the amount of crosslinking agents and sebacate segments along the main chains of copolymers.
基金Funded by the National Natural Science Foundation of China(No.51303115)
文摘We have analyzed the photorefractive(PR) effect of a polymer composite was reported which combines a novel bi-functional poly(N-vinyl)-3-[p-nitrophenylazo]carbazolyl(PVNPAK) and 2,4,7-trinitro-9-fluorenone(TNF). PVNPAK was synthesized by a post-azo-coupling reaction, with an azo derivative as the electrooptic chromophore and carbazolyl as photoconductive moiety. The asymmetric two-beam coupling gain of 13.9 cm-1 and diffraction efficiency of 1.2% for poled polymer film fabricated using a corona poling are obtained at the wavelength of 647.1 nm, confirming photorefractivity. We interpreted this result as the orientational enhancement, in which the spatial charge field may enhance the modulated orientation of the azobenzen chromophore. It is unexpected that the photorefractive gain of 9.5 cm-1 for the unpoled polymer film also was observed without external field in two-beam coupling(TBC) experiment. This phenomenon is attributed to a light-induced orientational grating when the azobenzene groups are illuminated by polarized light.
文摘The C60 grafted poly(N-vinyl carbazole) (PVK) polymer(CGP) was prepared by simple radical polymerization initiated by BPO at 90℃.The products were characterized by UV-Vis, FTIR, GPC and fluorescence and it was proven that C60 was grafted covalently to the PVK. The C60 moiety in the product was about 1. 2% (mass fraction). The photoconductlvity study revealed that the photoconductivity of PVK was improved obviously through grafting C60.The half time of light decaying (t1/2) of CGP reached 0. 35 s.
文摘PVK or PVK-C60 solution was dropped onto the alumina membrane and the solution was filled into the channel of the membrane due to the capillary action. As the solvent evaporation, the nanotubes were formed. The morphology of the sample was examined by SEM and fluorescence of PVK and PVK-C60 was determined. Emis- sion intensity of PVK was weakened by C60, indicating that C60 improved the conductive property of PVK nan- otubes.