Surface-grafted poly(ethylene glycol) (PEG) molecules are known to prevent protein adsorption to the surface. Nitinol samples were coated under tetraglyme ECR cold plasma conditions to enhance its biocompatibility. Th...Surface-grafted poly(ethylene glycol) (PEG) molecules are known to prevent protein adsorption to the surface. Nitinol samples were coated under tetraglyme ECR cold plasma conditions to enhance its biocompatibility. The modified Nitinol surfaces were characterized by high resolution ESCA and contact angle, it was demonstrated that the deposited PEG-like coatings were built up mainly of-CH2-CH2-O- linkages in surfaces. The surface wettability of the modified Nitinol was increased compared with the control surface. Human plasma protein was adsorbed on Nitinol evaluated by SEM, the protein adsorption on modified surfaces decreased rapidly. Thus, the potential benefits of cold plasma technique will be of use to the biomedical industries improving the biocompatibility of metals.展开更多
The macromolecular structures on nitinol surfaces were prepared by ECR microwave cold-plasma of tetraglyme conditions. The surface chemistry was characterized by high resolution ESCA. The results showed that th...The macromolecular structures on nitinol surfaces were prepared by ECR microwave cold-plasma of tetraglyme conditions. The surface chemistry was characterized by high resolution ESCA. The results showed that the modified nitinol surfaces were built up mainly of -CH2-CH2-O- linkages and were particularly effective in preventing platelet adhesion.展开更多
Adhesion strength is an important target in evaluating the quality of coating layers.The traditional way of adhesion strength test is bonding pull off method for thick layers and scratch test for thin films.The drawb...Adhesion strength is an important target in evaluating the quality of coating layers.The traditional way of adhesion strength test is bonding pull off method for thick layers and scratch test for thin films.The drawbacks of these two methods are discussed in this paper,and an evaluating method for adhesion strength of coating by burying beforehand specimen is proposed.The adhesion strength of samples is measured with two methods.The dispersity of testing data is lower than that in the ASTM C663 79 Standard.展开更多
High molecular weight hyperbranched polyarylenes were synthesized in high yields by one-pot copolycyclotrimerizations of 2,5-diethynylthiophene (1), 4,4' -biphenyldiyne (2) and 2,7-diethynylfluorenes (3) with l-he...High molecular weight hyperbranched polyarylenes were synthesized in high yields by one-pot copolycyclotrimerizations of 2,5-diethynylthiophene (1), 4,4' -biphenyldiyne (2) and 2,7-diethynylfluorenes (3) with l-heptyne (4) and 1-dodecyne (5) using TaCl5·Ph4Sn catalysts in toluene. The structures and properties of the polymers were characterized and evaluated by 1R, NMR, TGA, UV, fluorescence and optical limiting analyses. All the polymers possess high thermal stability and emit strong blue light upon UV irradiation, whose intensities are higher than that from poly( 1 -phenyl-1 -octyne) ( PPO) , a well-known highly luminescent disubstitut-ed polyacetylene. Little aggregation-induced red shift in the photoluminescence is observed in the thin films of the polymers.展开更多
基金The project was supported by the National Natural Science Foundation of China(NSFC)(Grant No.19972071,50274065)subsidized by the Special Funds for Major State Basic Research Project(“973”Project)(Grant No.2002CB412704).
文摘Surface-grafted poly(ethylene glycol) (PEG) molecules are known to prevent protein adsorption to the surface. Nitinol samples were coated under tetraglyme ECR cold plasma conditions to enhance its biocompatibility. The modified Nitinol surfaces were characterized by high resolution ESCA and contact angle, it was demonstrated that the deposited PEG-like coatings were built up mainly of-CH2-CH2-O- linkages in surfaces. The surface wettability of the modified Nitinol was increased compared with the control surface. Human plasma protein was adsorbed on Nitinol evaluated by SEM, the protein adsorption on modified surfaces decreased rapidly. Thus, the potential benefits of cold plasma technique will be of use to the biomedical industries improving the biocompatibility of metals.
基金supported by the National Natural Science Foundation of China(NNSFC)(Grant No.19972071,50274065)subsidized by the Special Funds for Major State Basic Research Project("973"Project)(Grant No.2002CB412704)
文摘The macromolecular structures on nitinol surfaces were prepared by ECR microwave cold-plasma of tetraglyme conditions. The surface chemistry was characterized by high resolution ESCA. The results showed that the modified nitinol surfaces were built up mainly of -CH2-CH2-O- linkages and were particularly effective in preventing platelet adhesion.
文摘Adhesion strength is an important target in evaluating the quality of coating layers.The traditional way of adhesion strength test is bonding pull off method for thick layers and scratch test for thin films.The drawbacks of these two methods are discussed in this paper,and an evaluating method for adhesion strength of coating by burying beforehand specimen is proposed.The adhesion strength of samples is measured with two methods.The dispersity of testing data is lower than that in the ASTM C663 79 Standard.
基金Jointly funded by the Hongkong Research Grants Council (HKUST6149/97P,and 6187/99P) and Natural Science Foundation of Hubei Province(2000J024)
文摘High molecular weight hyperbranched polyarylenes were synthesized in high yields by one-pot copolycyclotrimerizations of 2,5-diethynylthiophene (1), 4,4' -biphenyldiyne (2) and 2,7-diethynylfluorenes (3) with l-heptyne (4) and 1-dodecyne (5) using TaCl5·Ph4Sn catalysts in toluene. The structures and properties of the polymers were characterized and evaluated by 1R, NMR, TGA, UV, fluorescence and optical limiting analyses. All the polymers possess high thermal stability and emit strong blue light upon UV irradiation, whose intensities are higher than that from poly( 1 -phenyl-1 -octyne) ( PPO) , a well-known highly luminescent disubstitut-ed polyacetylene. Little aggregation-induced red shift in the photoluminescence is observed in the thin films of the polymers.
