The novel cyclic trithiocarbonate was synthesized by dialkylation of trithiocarbonate anion with 2,2＇- bis（bromomethyl）biphenyl in a two-phase system using an onium salt as a phase-transfer agent. Styrene polymeriz...The novel cyclic trithiocarbonate was synthesized by dialkylation of trithiocarbonate anion with 2,2＇- bis（bromomethyl）biphenyl in a two-phase system using an onium salt as a phase-transfer agent. Styrene polymerization was carried out in the presence of cyclic trithiocarbonate （CTTC）. CTTC undergoes ring opening-polymerization and the incorporated trithiocarbonate moiety derived from CTTC performs as the reversible addition-fragmentation chain transfer （RAFT） agent. Through this mechanism, multiblock polys-tyrenes containing various narrow polydispersity blocks can be prepared.展开更多
The effects of ethylene vinyl acetate copelymer （EVA） as a compatibilizer on the dispersion of organically modified montmorillonite（org-MMT） into low-density polyethylene（LDPE） during melt extrusion compounding ...The effects of ethylene vinyl acetate copelymer （EVA） as a compatibilizer on the dispersion of organically modified montmorillonite（org-MMT） into low-density polyethylene（LDPE） during melt extrusion compounding were studied. The X-ray diffraction patterns reveal that as compared with LDPE, EVA can intercalate more easily into the interlay gallery of org-MMT when the composites contain a low org-MMT content. Exfoliated LDPE/org-MMT nanocompesites in the presence of an EVA compatibilizer could be prepared by using a two-step melt compounding technique with a twin-screw extruder.展开更多
Both four-ann star-shaped poly（ε-caprolactone） （4sPCL） and two-ann linear PCL （2LPCL） were synthesized and their inclusion complexation with α-cyclodextrin （α-CD） were studied. The inclusion complexes （ICs...Both four-ann star-shaped poly（ε-caprolactone） （4sPCL） and two-ann linear PCL （2LPCL） were synthesized and their inclusion complexation with α-cyclodextrin （α-CD） were studied. The inclusion complexes （ICs） formed between the PCL polymers and α-CD were characterized by ^1H-NMR, DSC, TGA, WAXD, and FT-1R, respectively. Both branch ann number and molecular weight of the PCL polymers have apparent effect on the stoichiometry （CL：CD, mol：mol） of these ICs. All these analytical results indicate that the branch arms of the PCL polymers are incorporated into the hydrophobic α-CD cavities and their original crystalline properties are completely suppressed. Moreover, the inclusion complexation between two-ann linear or four-ann star-shaped PCL polymers and α-CD not only enhances the thermal stability of the guest PCL polymers but also improves that of α-CD.展开更多
Poly（phenylacetylene）s beating monosaccharide pendant groups are synthesized in high yields by [Rh（nbd）Cl]2 catalyst. The polymers have high molecular weights and give satisfactory spectroscopic data corresponding...Poly（phenylacetylene）s beating monosaccharide pendant groups are synthesized in high yields by [Rh（nbd）Cl]2 catalyst. The polymers have high molecular weights and give satisfactory spectroscopic data corresponding to their molecular structures. They are thermally quite stable （≥ 300℃） and show strong circular dichroism signals in the visible spectral region owing to the helicity of the polyene backbone. The monosaccharide-containing polyacetylenes are cytophilic and can stimulate the growth of living cells.展开更多
A perylene bisimide dye covalently bonded with a hydrogen-bond formation group of 1, 3, 5-triazine-2, 4-diamine has been synthesized. Its casting films show a charge carrier mobility over 10^-3 cm^2/Vs, which is in th...A perylene bisimide dye covalently bonded with a hydrogen-bond formation group of 1, 3, 5-triazine-2, 4-diamine has been synthesized. Its casting films show a charge carrier mobility over 10^-3 cm^2/Vs, which is in the range of the highest values found for other promising charge transport materials suitable for solution processable technique.展开更多
The photoconductivities of a series of novel polyacetylene derivatives （PAs） serving as charge generation materials in the single-layered photoreceptors were investigated using photoinduced xerographic discharge tec...The photoconductivities of a series of novel polyacetylene derivatives （PAs） serving as charge generation materials in the single-layered photoreceptors were investigated using photoinduced xerographic discharge technique. It was found that the substitution can improve the photosensitivity of PAs by increasing the conjugation of π electrons. When the substituent is itself photoconductive, the photoconductivity becomes even higher. It can be concluded from cyclic voltammetry that when the HOMO level of the polymer is closer to that of the charge transport material, the photoconduction performance will be better.展开更多
This review discusses recent studies on dendrimer-based nanoparticles in cancer chemotherapy and gene therapy. In order to achieve the high efficacy and low side effects of chemotherapy and gene therapy, it is essenti...This review discusses recent studies on dendrimer-based nanoparticles in cancer chemotherapy and gene therapy. In order to achieve the high efficacy and low side effects of chemotherapy and gene therapy, it is essential to combine the unique features of dendrimers and the specific tumor microenvironment to target delivery and control release of therapeutic agents to tumor tissues and cells. Strategies to design the dendrimer-based delivery system in this review include non-modified dendrimers, dendrimer conjugates, assembled amphiphilic dendrimers, nanohybrid dendrimer carriers and dendrimers with inherent activity. In addition, specific functional groups on these dendrimers as stimuli-responsive system for targeting delivery and controlled release of therapeutic agents are discussed.展开更多
基金This work was supported by the National Science Foundation of China (No. 20204013).
文摘The novel cyclic trithiocarbonate was synthesized by dialkylation of trithiocarbonate anion with 2,2＇- bis（bromomethyl）biphenyl in a two-phase system using an onium salt as a phase-transfer agent. Styrene polymerization was carried out in the presence of cyclic trithiocarbonate （CTTC）. CTTC undergoes ring opening-polymerization and the incorporated trithiocarbonate moiety derived from CTTC performs as the reversible addition-fragmentation chain transfer （RAFT） agent. Through this mechanism, multiblock polys-tyrenes containing various narrow polydispersity blocks can be prepared.
文摘The effects of ethylene vinyl acetate copelymer （EVA） as a compatibilizer on the dispersion of organically modified montmorillonite（org-MMT） into low-density polyethylene（LDPE） during melt extrusion compounding were studied. The X-ray diffraction patterns reveal that as compared with LDPE, EVA can intercalate more easily into the interlay gallery of org-MMT when the composites contain a low org-MMT content. Exfoliated LDPE/org-MMT nanocompesites in the presence of an EVA compatibilizer could be prepared by using a two-step melt compounding technique with a twin-screw extruder.
基金This work was supported by the National Natural Science Foundation of China (No. 20404007).
文摘Both four-ann star-shaped poly（ε-caprolactone） （4sPCL） and two-ann linear PCL （2LPCL） were synthesized and their inclusion complexation with α-cyclodextrin （α-CD） were studied. The inclusion complexes （ICs） formed between the PCL polymers and α-CD were characterized by ^1H-NMR, DSC, TGA, WAXD, and FT-1R, respectively. Both branch ann number and molecular weight of the PCL polymers have apparent effect on the stoichiometry （CL：CD, mol：mol） of these ICs. All these analytical results indicate that the branch arms of the PCL polymers are incorporated into the hydrophobic α-CD cavities and their original crystalline properties are completely suppressed. Moreover, the inclusion complexation between two-ann linear or four-ann star-shaped PCL polymers and α-CD not only enhances the thermal stability of the guest PCL polymers but also improves that of α-CD.
基金This work was partially supported by the Research Grants Council of Hong Kong(Nos. 602706, HKU2/05C, 603505,603304, and 664903).
文摘Poly（phenylacetylene）s beating monosaccharide pendant groups are synthesized in high yields by [Rh（nbd）Cl]2 catalyst. The polymers have high molecular weights and give satisfactory spectroscopic data corresponding to their molecular structures. They are thermally quite stable （≥ 300℃） and show strong circular dichroism signals in the visible spectral region owing to the helicity of the polyene backbone. The monosaccharide-containing polyacetylenes are cytophilic and can stimulate the growth of living cells.
基金This research was supported by the National Natural Scientific Foundation of China(No.90101008)973 project(No.2002CB613401)of the MST of P.R.China.
文摘A perylene bisimide dye covalently bonded with a hydrogen-bond formation group of 1, 3, 5-triazine-2, 4-diamine has been synthesized. Its casting films show a charge carrier mobility over 10^-3 cm^2/Vs, which is in the range of the highest values found for other promising charge transport materials suitable for solution processable technique.
基金This work was supported by the National Natural Science Foundation of China(Nos.50225312,50318001,50433020).
文摘The photoconductivities of a series of novel polyacetylene derivatives （PAs） serving as charge generation materials in the single-layered photoreceptors were investigated using photoinduced xerographic discharge technique. It was found that the substitution can improve the photosensitivity of PAs by increasing the conjugation of π electrons. When the substituent is itself photoconductive, the photoconductivity becomes even higher. It can be concluded from cyclic voltammetry that when the HOMO level of the polymer is closer to that of the charge transport material, the photoconduction performance will be better.
基金supported by the National Natural Science Foundation of China (81601594, 51690153, 21474045 and 21720102005)
文摘This review discusses recent studies on dendrimer-based nanoparticles in cancer chemotherapy and gene therapy. In order to achieve the high efficacy and low side effects of chemotherapy and gene therapy, it is essential to combine the unique features of dendrimers and the specific tumor microenvironment to target delivery and control release of therapeutic agents to tumor tissues and cells. Strategies to design the dendrimer-based delivery system in this review include non-modified dendrimers, dendrimer conjugates, assembled amphiphilic dendrimers, nanohybrid dendrimer carriers and dendrimers with inherent activity. In addition, specific functional groups on these dendrimers as stimuli-responsive system for targeting delivery and controlled release of therapeutic agents are discussed.
