A new kind of polybenzoxazine could be synthesized by electrochemical method in acetonitrile/alkaline aqueous solution. The obtained polymer shows good heat resistance properties.
A study concerning the effect of vibration on the crystal structure and morphology for isotactic polypropylene(iPP) was conducted. The crystallite size, crystal structure and crystallinity of iPP under or without vibr...A study concerning the effect of vibration on the crystal structure and morphology for isotactic polypropylene(iPP) was conducted. The crystallite size, crystal structure and crystallinity of iPP under or without vibration treatment were investigated by means of differential scanning calorimetry(DSC) and wide-angle X-ray diffraction(WAXD). The results reveal that the crystallinity of the vibrated samples decreases at a high cooling rate, but it remains constant at a low cooling rate because of the chain relaxation of iPP. It has been found that vibration obviously increases the content of β-form of crystal phase and the amount of β-crystal mainly depends on the vibration amplitude.展开更多
The multiwall carbon nanotube (MWCNT) bonded to 2, 9, 16, 23-tetraamino manganese phthalocyanine (TAMnPc) was obtained by covalent functionalization, and its chemical structure was characterized by TEM. The photocondu...The multiwall carbon nanotube (MWCNT) bonded to 2, 9, 16, 23-tetraamino manganese phthalocyanine (TAMnPc) was obtained by covalent functionalization, and its chemical structure was characterized by TEM. The photoconductivity of single-layered photoreceptors, where MWCNT bonded by TAMnPc (MWCNT-b-TAMnPc) served as the charge generation material (CGM), was also studied.展开更多
The effect of cryogenic and heating treatment on the solution properties of rigid polymer nitrocellulose(NC)indilute tetrahydrofuran solution were studied with a sealed viscometer and a size exclusion chromatograph(SE...The effect of cryogenic and heating treatment on the solution properties of rigid polymer nitrocellulose(NC)indilute tetrahydrofuran solution were studied with a sealed viscometer and a size exclusion chromatograph(SEC),respectively.The experimental results show that the relative viscosity of NC solution decreases after repeated freezing-thawing treatment.The decreased viscosity value of NC could not be restored but decreased further after the solution beingre-heated.The experimental results of SEC are fully consistent with that of viscosity measurements.It is believed that theeffect of two treatments on NC solution both causes the apparent hydrodynamic volume to decrease.But they are assumed tobe ascribed to different mechanisms.展开更多
Upon excitation of porphyrin or perylene subunit, the porphyrin-perylene dyad exhibitsreversible fluorescence emitting and quenching by formation and neutralization of the protonatedporphyrin subunit, thereby providin...Upon excitation of porphyrin or perylene subunit, the porphyrin-perylene dyad exhibitsreversible fluorescence emitting and quenching by formation and neutralization of the protonatedporphyrin subunit, thereby providing a prototype of molecular fluorescence switch working in anexpanded spectral range.展开更多
Polymer chain coils with entanglement is a crucial scale of structures in polymer materials since their relaxationtimes are matching practical processing times.Based on the phenomenological model of polymer chain coil...Polymer chain coils with entanglement is a crucial scale of structures in polymer materials since their relaxationtimes are matching practical processing times.Based on the phenomenological model of polymer chain coils and a new finiteelement approach,we have designed a computer software including solver,pre-and post-processing modules,and developeda digital analysis technology for the morphology of polymer chain coils in flow fields(DAMPC).Using this technology wemay simulate the morphology development of chain coils in various flow fields,such as simple shear flow,elongational flow,and any complex flow at transient or steady state.The applications made up to now show that the software predictions arecomparable with experimental results.展开更多
Poly (phthalazinone ether sulfone ketone) (PPESK) was melt blended with bisphenol-A polysulfone oligomer (O-PSF) to produce a thermoplastic polymer blends. The miscibility, thermal stability, rheological and mechanica...Poly (phthalazinone ether sulfone ketone) (PPESK) was melt blended with bisphenol-A polysulfone oligomer (O-PSF) to produce a thermoplastic polymer blends. The miscibility, thermal stability, rheological and mechanical properties of the blends were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and capillary rheometry. The blends showed single Tg over the composition range and possess homogeneous microstructure. The addition of O-PSF slightly affected the thermal properties of the blends. PSF oligomer, as a processing aid, could markedly improve the processability of the PPESK. In addition, the mechanical properties of the blends were increased, to some degree, by adding O-PSF.展开更多
A novel aromatic diacid, 4, 4'-bis[2-(4-carboxyphenyl)phthalazin-1-one-4-yl]-bisphenyl ether III, containing bisphthalazinone and ether linkages was prepared from nucleophilic substitution of p-chlorobenzonitril...A novel aromatic diacid, 4, 4'-bis[2-(4-carboxyphenyl)phthalazin-1-one-4-yl]-bisphenyl ether III, containing bisphthalazinone and ether linkages was prepared from nucleophilic substitution of p-chlorobenzonitrile with the bisphenol-like monomer I, followed by alkaline hydrolysis of the intermediate dinitrile II. A series of poly(ether amide)s containing bisphthala- zinone and ether linkages derived from diacid III and aromatic diamines were synthesized by one-step solution condensation polymerization using triphenyl phosphite and pyridine as condensing agents. Moreover, the properties of poly(ether amide)s including thermal stability, solubility and crystallinity were also studied.展开更多
An oxyethylene/oxybutylene block copolymer with asymmetric volume fraction (E115B105) was blended with oxybutylene homopolymer (Bh) at different volume fractions of the block Crystallization behavior of the blends was...An oxyethylene/oxybutylene block copolymer with asymmetric volume fraction (E115B105) was blended with oxybutylene homopolymer (Bh) at different volume fractions of the block Crystallization behavior of the blends was studied and was compared with that of the blends from a symmetric block copolymer (E114B56). It was found that the crystallization temperature of E115B103/B28 blend is lower than that of the blends from symmetric block copolymer. For the blend with = 0.30 breakout crystallization with an Avrami exponent n 3.0 is observed. At = 0.22 the blend exhibits a variable crystallization behavior: confined crystallization with n 1.0 at lower crystallization temperatures but breakout crystallization at high crystallization temperatures. For the blend with = 0.14 and sphere morphology confined crystallization occurs at all crystallization temperatures studied. When compared with the blends from symmetric block copolymer, confined crystallization occurs more easily in the E115B103/B28 blends. The SAXS results agree with the isothermal crystallization kinetics. Deformation of the confined crystalline block is observed in the blend with =0.14 and mixed lamellar and cylinder morphologies in the blend with = 0.22.展开更多
Europium bisphthalocyanine (EuPc2) nanowires were prepared by electrochemical deposition method. Scanning electron microscopy (SEM) images show the evolution of the morphologies of nanowires obtained under different ...Europium bisphthalocyanine (EuPc2) nanowires were prepared by electrochemical deposition method. Scanning electron microscopy (SEM) images show the evolution of the morphologies of nanowires obtained under different deposition time (Td). The optical properties of europium bisphthalocyanine films were studied by UV-Vis absorption spectra. The morphology of EuPc2 nanowires could be controlled by changing deposition conditions, which provides a useful method to make organic nanowires.展开更多
A new diamine, disodium 4, 4-di(4-aminophenoxy)-3, 3-disulfonate-1, 1- diphenyl- ketone, was prepared from the nucleophilic substitution of disodium 4, 4- difluoro-3, 3-di- sulfonate-1, 1-diphenylketone and p-aminophe...A new diamine, disodium 4, 4-di(4-aminophenoxy)-3, 3-disulfonate-1, 1- diphenyl- ketone, was prepared from the nucleophilic substitution of disodium 4, 4- difluoro-3, 3-di- sulfonate-1, 1-diphenylketone and p-aminophenol. Polymerization of this diamine and 4, 4-diamino-1, 1- diphenyl ether with 3, 3, 4, 4-tetracarboxyl dianhydride-1, 1- diphenyl ketone gave ion-exchange copolyimide. The new diamine and its polyimide were characterized with 1H-NMR and FT-IR.展开更多
A side-on liquid crystalline monomer,2,5-bis[(4-hexyloxyphenyl)oxycarbonyl]styrene)(HPCS),was successfullypolymerized via atom transfer radical polymerization(ATRP).The polymerization was catalyzed by CuBr/PMDETA inch...A side-on liquid crystalline monomer,2,5-bis[(4-hexyloxyphenyl)oxycarbonyl]styrene)(HPCS),was successfullypolymerized via atom transfer radical polymerization(ATRP).The polymerization was catalyzed by CuBr/PMDETA inchlorobenzene at 90℃ with(1-bromoethyl)benzene as the initiator.The polymers have narrow MWD.It is the secondexample of mesogen-jacketed liquid crystalline polymer(MJLCP)prepared by ATRP.展开更多
Spectroscopic methods are used to investigate coordination structure of N-picolylpolyurethane transition metal complexes(PUPYM,M=Co^2+ and Ni^2+) .Geometrical arrangement of ligands in first-shell coordination sphere ...Spectroscopic methods are used to investigate coordination structure of N-picolylpolyurethane transition metal complexes(PUPYM,M=Co^2+ and Ni^2+) .Geometrical arrangement of ligands in first-shell coordination sphere of metal ions is postulated to be tetrahedral CoL2Cl2 and octahedral NiL2-Cl2Z2.where L is the picolyl group and Z is a hydrate.From extended X-ray absorption fine structure (EXAFS) analysis,bond lengths for metal-chlorine and metal-ligand of PUPYM are similar to those of small molecular weight transition metal complexes.A two-phase model of PUPYM which best describes the experimental data of DMTA and SAXS.is proposed.One microphase is the hard domain of self segregated haed segments brought about by metal-ligand interaction.and the other phase is the matrix of soft segments.Transition metal ion-ligand moieties and their interactions dominate the macroscopic thermal behavior of PUPYM.The ligand field stabilization energy difference(ΔLFSE) between mteal d-electrons in complexes with two picolyl ligands in the coordination sphere of metal ions and complexes maintaining one picolyl ligand as coordination pendent group is calculated on the basis of observed coordination structure,and it represents the energy supplied to split coordination cross-links.ΔLFSE of polyurethane nickel(II) complex is larger than that of the cobalt(II) complex,Since the mobility of hard segments is in inverse proportion to the strength of coordination cross-links.a higher α-transition temperature of PUPYNi^2+ with respect to PUPYCo^2+ is found as expected.展开更多
Poly(acrylic acid) (PAA) gel network with only chemical crosslinking and hydrophobically modified PAA (HM-PAA) gels with both chemical and physical crosslinking were synthesized by radical polymerization in tert-butan...Poly(acrylic acid) (PAA) gel network with only chemical crosslinking and hydrophobically modified PAA (HM-PAA) gels with both chemical and physical crosslinking were synthesized by radical polymerization in tert-butanol, using ethylene glycol dimethacrylate (EGDMA) as crosslinker, and 2-(N-ethylperfluorooctanesulfoamido)ethyl methacrylate (FMA), stearyl acrylate (SA) or lauryl acrylate (LA) as hydrophobic comonomer respectively. The effect of the fractions and the species of the hydrophobes on swelling properties of HM-PAA gels and the interaction of gels and surfactants were studied. The results showed that the swelling ratio of HM-PAA gels exhibited a sharp decrease with increasing hydrophobic comonomer concentration, which could be ascribed to the formation of strong hydrophobic association among hydrophobic groups. It was proved that two kinds of binding mechanisms of surfactant/gel and different kinds of hydrophobic clusters existed in gels containing both physical and chemical networks.展开更多
文摘A new kind of polybenzoxazine could be synthesized by electrochemical method in acetonitrile/alkaline aqueous solution. The obtained polymer shows good heat resistance properties.
基金Supported by the National Science Funds for Distinguished Young Scholars(No.5 0 12 5 312 ) Special Funds for MajorState Basic Research Project of China(No.G19990 6 4 80 0 ) and Key Program of the National Natural Science Foundation ofChina(No.5 0 1
文摘A study concerning the effect of vibration on the crystal structure and morphology for isotactic polypropylene(iPP) was conducted. The crystallite size, crystal structure and crystallinity of iPP under or without vibration treatment were investigated by means of differential scanning calorimetry(DSC) and wide-angle X-ray diffraction(WAXD). The results reveal that the crystallinity of the vibrated samples decreases at a high cooling rate, but it remains constant at a low cooling rate because of the chain relaxation of iPP. It has been found that vibration obviously increases the content of β-form of crystal phase and the amount of β-crystal mainly depends on the vibration amplitude.
文摘The multiwall carbon nanotube (MWCNT) bonded to 2, 9, 16, 23-tetraamino manganese phthalocyanine (TAMnPc) was obtained by covalent functionalization, and its chemical structure was characterized by TEM. The photoconductivity of single-layered photoreceptors, where MWCNT bonded by TAMnPc (MWCNT-b-TAMnPc) served as the charge generation material (CGM), was also studied.
基金This work was financially supported by the funds of Jiangsu ScienceTechnology Department(JH03-013,JHjd03-008).
文摘The effect of cryogenic and heating treatment on the solution properties of rigid polymer nitrocellulose(NC)indilute tetrahydrofuran solution were studied with a sealed viscometer and a size exclusion chromatograph(SEC),respectively.The experimental results show that the relative viscosity of NC solution decreases after repeated freezing-thawing treatment.The decreased viscosity value of NC could not be restored but decreased further after the solution beingre-heated.The experimental results of SEC are fully consistent with that of viscosity measurements.It is believed that theeffect of two treatments on NC solution both causes the apparent hydrodynamic volume to decrease.But they are assumed tobe ascribed to different mechanisms.
基金This research was supported by the National Natural Science Foundation of China(Grant No.50073018)the authors are also thankful to the support from the Key Laboratory of Supramolecular Structure and Materials in Jilin University.
文摘Upon excitation of porphyrin or perylene subunit, the porphyrin-perylene dyad exhibitsreversible fluorescence emitting and quenching by formation and neutralization of the protonatedporphyrin subunit, thereby providing a prototype of molecular fluorescence switch working in anexpanded spectral range.
基金This work was supported by the research grants from the National Natural Science Foundation of China(No.50290090No.20204007+2 种基金No.20174024)National 863 project of China(No.2002AA336120)the Doctoral Foundation of National Education Committee of China(
文摘Polymer chain coils with entanglement is a crucial scale of structures in polymer materials since their relaxationtimes are matching practical processing times.Based on the phenomenological model of polymer chain coils and a new finiteelement approach,we have designed a computer software including solver,pre-and post-processing modules,and developeda digital analysis technology for the morphology of polymer chain coils in flow fields(DAMPC).Using this technology wemay simulate the morphology development of chain coils in various flow fields,such as simple shear flow,elongational flow,and any complex flow at transient or steady state.The applications made up to now show that the software predictions arecomparable with experimental results.
基金This work was supported by the National Natural Science Foundation of China(No.59473901).
文摘Poly (phthalazinone ether sulfone ketone) (PPESK) was melt blended with bisphenol-A polysulfone oligomer (O-PSF) to produce a thermoplastic polymer blends. The miscibility, thermal stability, rheological and mechanical properties of the blends were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and capillary rheometry. The blends showed single Tg over the composition range and possess homogeneous microstructure. The addition of O-PSF slightly affected the thermal properties of the blends. PSF oligomer, as a processing aid, could markedly improve the processability of the PPESK. In addition, the mechanical properties of the blends were increased, to some degree, by adding O-PSF.
文摘A novel aromatic diacid, 4, 4'-bis[2-(4-carboxyphenyl)phthalazin-1-one-4-yl]-bisphenyl ether III, containing bisphthalazinone and ether linkages was prepared from nucleophilic substitution of p-chlorobenzonitrile with the bisphenol-like monomer I, followed by alkaline hydrolysis of the intermediate dinitrile II. A series of poly(ether amide)s containing bisphthala- zinone and ether linkages derived from diacid III and aromatic diamines were synthesized by one-step solution condensation polymerization using triphenyl phosphite and pyridine as condensing agents. Moreover, the properties of poly(ether amide)s including thermal stability, solubility and crystallinity were also studied.
基金This project was supported by the National Natural Science Foundation of China (20374046) and by the Excellent YoungTeachers Program of MOE, China.
文摘An oxyethylene/oxybutylene block copolymer with asymmetric volume fraction (E115B105) was blended with oxybutylene homopolymer (Bh) at different volume fractions of the block Crystallization behavior of the blends was studied and was compared with that of the blends from a symmetric block copolymer (E114B56). It was found that the crystallization temperature of E115B103/B28 blend is lower than that of the blends from symmetric block copolymer. For the blend with = 0.30 breakout crystallization with an Avrami exponent n 3.0 is observed. At = 0.22 the blend exhibits a variable crystallization behavior: confined crystallization with n 1.0 at lower crystallization temperatures but breakout crystallization at high crystallization temperatures. For the blend with = 0.14 and sphere morphology confined crystallization occurs at all crystallization temperatures studied. When compared with the blends from symmetric block copolymer, confined crystallization occurs more easily in the E115B103/B28 blends. The SAXS results agree with the isothermal crystallization kinetics. Deformation of the confined crystalline block is observed in the blend with =0.14 and mixed lamellar and cylinder morphologies in the blend with = 0.22.
文摘Europium bisphthalocyanine (EuPc2) nanowires were prepared by electrochemical deposition method. Scanning electron microscopy (SEM) images show the evolution of the morphologies of nanowires obtained under different deposition time (Td). The optical properties of europium bisphthalocyanine films were studied by UV-Vis absorption spectra. The morphology of EuPc2 nanowires could be controlled by changing deposition conditions, which provides a useful method to make organic nanowires.
文摘A new diamine, disodium 4, 4-di(4-aminophenoxy)-3, 3-disulfonate-1, 1- diphenyl- ketone, was prepared from the nucleophilic substitution of disodium 4, 4- difluoro-3, 3-di- sulfonate-1, 1-diphenylketone and p-aminophenol. Polymerization of this diamine and 4, 4-diamino-1, 1- diphenyl ether with 3, 3, 4, 4-tetracarboxyl dianhydride-1, 1- diphenyl ketone gave ion-exchange copolyimide. The new diamine and its polyimide were characterized with 1H-NMR and FT-IR.
基金This work was supported by the National Natural Science Foundation of China(No.20134010)the Science Research Fund of the Chinese Ministry of Education(Nos.01001,104005).
文摘A side-on liquid crystalline monomer,2,5-bis[(4-hexyloxyphenyl)oxycarbonyl]styrene)(HPCS),was successfullypolymerized via atom transfer radical polymerization(ATRP).The polymerization was catalyzed by CuBr/PMDETA inchlorobenzene at 90℃ with(1-bromoethyl)benzene as the initiator.The polymers have narrow MWD.It is the secondexample of mesogen-jacketed liquid crystalline polymer(MJLCP)prepared by ATRP.
文摘Spectroscopic methods are used to investigate coordination structure of N-picolylpolyurethane transition metal complexes(PUPYM,M=Co^2+ and Ni^2+) .Geometrical arrangement of ligands in first-shell coordination sphere of metal ions is postulated to be tetrahedral CoL2Cl2 and octahedral NiL2-Cl2Z2.where L is the picolyl group and Z is a hydrate.From extended X-ray absorption fine structure (EXAFS) analysis,bond lengths for metal-chlorine and metal-ligand of PUPYM are similar to those of small molecular weight transition metal complexes.A two-phase model of PUPYM which best describes the experimental data of DMTA and SAXS.is proposed.One microphase is the hard domain of self segregated haed segments brought about by metal-ligand interaction.and the other phase is the matrix of soft segments.Transition metal ion-ligand moieties and their interactions dominate the macroscopic thermal behavior of PUPYM.The ligand field stabilization energy difference(ΔLFSE) between mteal d-electrons in complexes with two picolyl ligands in the coordination sphere of metal ions and complexes maintaining one picolyl ligand as coordination pendent group is calculated on the basis of observed coordination structure,and it represents the energy supplied to split coordination cross-links.ΔLFSE of polyurethane nickel(II) complex is larger than that of the cobalt(II) complex,Since the mobility of hard segments is in inverse proportion to the strength of coordination cross-links.a higher α-transition temperature of PUPYNi^2+ with respect to PUPYCo^2+ is found as expected.
文摘Poly(acrylic acid) (PAA) gel network with only chemical crosslinking and hydrophobically modified PAA (HM-PAA) gels with both chemical and physical crosslinking were synthesized by radical polymerization in tert-butanol, using ethylene glycol dimethacrylate (EGDMA) as crosslinker, and 2-(N-ethylperfluorooctanesulfoamido)ethyl methacrylate (FMA), stearyl acrylate (SA) or lauryl acrylate (LA) as hydrophobic comonomer respectively. The effect of the fractions and the species of the hydrophobes on swelling properties of HM-PAA gels and the interaction of gels and surfactants were studied. The results showed that the swelling ratio of HM-PAA gels exhibited a sharp decrease with increasing hydrophobic comonomer concentration, which could be ascribed to the formation of strong hydrophobic association among hydrophobic groups. It was proved that two kinds of binding mechanisms of surfactant/gel and different kinds of hydrophobic clusters existed in gels containing both physical and chemical networks.