Hydroxyapatite （HAP） nanoparticles with uniform morphologies and controllable size were synthesized successfully by molecular template hydrothermal approach. The organic alcohols including ethanol, glycol, glycerol ...Hydroxyapatite （HAP） nanoparticles with uniform morphologies and controllable size were synthesized successfully by molecular template hydrothermal approach. The organic alcohols including ethanol, glycol, glycerol and butanol were used as templates to regulate the nucleation and crystal growth. The synthesized powders were characterized by X-ray diffraction, Fourier infrared spectrum and trans- mission electron microscopy. The results showed that the obtained HAP particles were uniform rod-like crystals, and the template molecular structures had significant effect on the morphology and size of HAP particles. The template molecules with longer hydrophobic groups resulted in longer particle length and larger aspect ratio. Compared with the concentration of template molecules, the template molecular structure showed larger influence on controlling the HAP morphology and size. Furthermore, the for- mation mechanism of these rod-like HAP particles prepared by alkyl alcohol templates was discussed. Moreover, hydrothermal treatment temperature and time could be also used for controlled preparation of HAP nanoparticles.展开更多
Granular hydroxyl-functionalized UHMWPE was successfully prepared through copolymerization of ethylene and 10-undecen-1-ol protected by tri-iso-butylaluminum using a titanium complex.[tBuNSiMe_(2)(2,7-tBu2Flu)]TiMe_(2...Granular hydroxyl-functionalized UHMWPE was successfully prepared through copolymerization of ethylene and 10-undecen-1-ol protected by tri-iso-butylaluminum using a titanium complex.[tBuNSiMe_(2)(2,7-tBu2Flu)]TiMe_(2) was activated in hexane by silica-supported modified-methylaluminoxane.Without any additional pretreatments,the obtained polymer powders were transformed into fibers through a gel-spinning and heat drawing process.When compared to fibers generated from the equivalent unfunctionalized UHMWPE or the commercial HUMWPE,both creep resistance and hydrophilic properties were improved in the hydroxy-functionalized UHMWPE fibers without losing tensile strength.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.51372004,21171034 and21271040)the Shanghai Municipal Natural Science Foundation for Youths(No.12ZR144100)"Chen Guang"project(No.12CG37)supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation
文摘Hydroxyapatite （HAP） nanoparticles with uniform morphologies and controllable size were synthesized successfully by molecular template hydrothermal approach. The organic alcohols including ethanol, glycol, glycerol and butanol were used as templates to regulate the nucleation and crystal growth. The synthesized powders were characterized by X-ray diffraction, Fourier infrared spectrum and trans- mission electron microscopy. The results showed that the obtained HAP particles were uniform rod-like crystals, and the template molecular structures had significant effect on the morphology and size of HAP particles. The template molecules with longer hydrophobic groups resulted in longer particle length and larger aspect ratio. Compared with the concentration of template molecules, the template molecular structure showed larger influence on controlling the HAP morphology and size. Furthermore, the for- mation mechanism of these rod-like HAP particles prepared by alkyl alcohol templates was discussed. Moreover, hydrothermal treatment temperature and time could be also used for controlled preparation of HAP nanoparticles.
基金This work was supported by the Fundamental Research Funds for the Central Universities(2232020A-05)National Natural Science Foundation of China(21174026)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning.
文摘Granular hydroxyl-functionalized UHMWPE was successfully prepared through copolymerization of ethylene and 10-undecen-1-ol protected by tri-iso-butylaluminum using a titanium complex.[tBuNSiMe_(2)(2,7-tBu2Flu)]TiMe_(2) was activated in hexane by silica-supported modified-methylaluminoxane.Without any additional pretreatments,the obtained polymer powders were transformed into fibers through a gel-spinning and heat drawing process.When compared to fibers generated from the equivalent unfunctionalized UHMWPE or the commercial HUMWPE,both creep resistance and hydrophilic properties were improved in the hydroxy-functionalized UHMWPE fibers without losing tensile strength.
