Prof Shang | The Hong Kong Polytechnic University (original) (raw)

Papers by Prof Shang

Applied Surface Science, 2011

Nine polycarboxylic acids were used to improve washing durability of hydrophobic cellulose fabric... more Nine polycarboxylic acids were used to improve washing durability of hydrophobic cellulose fabric finished by sol–gel method. By simultaneous forming ester-bridge between cellulose and silica layer by ester bond, polycarboxylic acids could anchor silica coating onto cellulose fabric to strengthen the adhesion of organic–inorganic hybrid coating. The wettability of treated fabrics was characterized by water contact angle, spray test and hydrostatic pressure test. The results showed that all investigated polycarboxylic acids could improve the durability. The polycarboxylic acid with proper distance between terminal carboxylic acid groups and number of carboxylic acid groups showed the highest durability. 1,2,3,4-butanetetracarboxylic acid (BTCA) led to the best durability of hydrophobic cellulose fabric with water contact angle of 137.6° (recovery percentage of 94.2%) after 30 washing times. The effect of BTCA on durability was characterized by scanning electron microscopy. This study demonstrated that the surface treatment using polycarboxylic acids and mixed organosilanes is a promising alternative for achieving durable hydrophobic fabrics.

Research Journal of Textile and Apparel, 2011

Journal of Macromolecular Science, Part B, 2015

Organic Electronics, 2012

Polymer Testing, 2010

Poly(trimethylene terephthalate)-poly(ethylene glycol) segmented copolyester (PTEG)/ multi-walled... more Poly(trimethylene terephthalate)-poly(ethylene glycol) segmented copolyester (PTEG)/ multi-walled carbon nanotube (MWCNT) nanocomposites with various MWCNT content and copolyester composition were prepared by solution blending and the effect of MWCNTs on the crystallization behavior of PTEG copolymers was explored by differential scanning calorimetry (DSC), depolarized light intensity (DLI) technique and polarized light microscopy (PLM). The dynamic crystallization and the crystallization morphology of the nanocomposites are discussed. The isothermal crystallization kinetics was analyzed by means of a two stage crystallization kinetics model. The results showed that MWCNTs take the role of an effective nucleating agent during composite crystallization and can expedite the process of crystallization of the PTEG matrix by providing more nucleation sites to the crystallizing phase, which results in the formation of smaller spherulites.

Journal of Nanoparticle Research, Jun 4, 2012

Journal of Polymer Science Part B: Polymer Physics, 2016

Ceramics International, 2014

AZO/Ag/AZO trilayer films were prepared on glass substrates by radio frequency (RF) magnetron spu... more AZO/Ag/AZO trilayer films were prepared on glass substrates by radio frequency (RF) magnetron sputtering technology. Crystal structure, surface morphology, visible transmittance, and color scale of the AZO/Ag/AZO coated trilayers as functions of Ag and AZO layers thickness were investigated by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM), optical transmittance spectra and CIELAB system. In addition, the electrical and infrared reflection properties of the coated trilayers were examined by four-point probe system and Fourier Transform Infrared Spectroscopy. The results indicated that the Ag inner layer started forming a continuous film at the thickness of 10 nm which was supported by XRD result of the distinct 200 and 220 Ag peaks. Besides, the highest average visible transmittance of 80.5% was obtained by the AZO (30 nm)/Ag (10 nm)/AZO (30 nm) structure. Furthermore, the lowest sheet resistivity of 4.36 Ω/sq and the highest infrared reflection rate of 96% in FIR region can be obtained by the AZO (30 nm)/Ag (13 nm)/AZO (30 nm) structure. The high infrared reflection property of the AZO/Ag/AZO trilayers makes it a promising candidate for energy conservation coatings.

Ceramics International, 2015

Radio Frequency (RF) magnetron sputtered TiO 2 thin films have been deposited on flexible textile... more Radio Frequency (RF) magnetron sputtered TiO 2 thin films have been deposited on flexible textile substrates such as polyester and cotton fabrics, yielding a flexible composite architecture. The structure of the composites was systematically investigated by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Contact Angle tester. The deposited TiO 2 thin films featured unique high porosity and amorphous structure which combined with the flexibility of the textile base show promise for photovoltaic applications.

Ceramics International, 2015

ABSTRACT Ag and AZO/Ag/AZO ceramic films were deposited on cotton fabrics by radio frequency (RF)... more ABSTRACT Ag and AZO/Ag/AZO ceramic films were deposited on cotton fabrics by radio frequency (RF) magnetron sputtering and systematically investigated by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy. Physical properties of the coated fabrics were evaluated by infrared reflection rate, air permeability and UPF value. Ag coated cotton fabrics presented an infrared reflection rate of 16% and the highest UPF values of 11.096. The AZO/Ag/AZO coated cotton fabrics exhibited an infrared reflection rate of 18% and the highest UPF values of 21.782. The prepared flexible cotton fabrics can provide UV radiation protection and infrared reflective properties, which make them promising materials for solar control applications.

Vacuum, 2014

a b s t r a c t AZO/Ag/AZO multilayer films were prepared on PET substrate by radio frequency (RF... more a b s t r a c t AZO/Ag/AZO multilayer films were prepared on PET substrate by radio frequency (RF) magnetron sputtering technology. The prepared films were investigated by optical transmittance spectra, a fourpoint probe system, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM), and Fourier Transform Infrared Spectroscopy. The results indicate that Ag inner layer starts forming a continuous film at the thickness about 10 nm. The sample with 10 nm's Ag inner layer exhibited the highest average visible transmittance of 78.5% and 91%'s infrared reflection rate in FIR region. Sample with 15 nm's Ag inner layer showed the highest infrared reflection rate of 96% in FIR region. The high visible transmittance and infrared reflection property of the AZO/Ag/AZO multilayer film makes it a promising candidate for solar films.

Solar Energy Materials and Solar Cells, 2014

Al-doped ZnO (AZO) films were prepared on glass substrates by radio frequency (RF) magnetron sput... more Al-doped ZnO (AZO) films were prepared on glass substrates by radio frequency (RF) magnetron sputtering technology. Crystal structure, surface morphology, electrical properties and infrared reflection of the AZO films were systematically investigated by X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), Hall measurement system and Fourier Transform infrared spectroscopy, respectively. In addition, the corresponding properties of AZO films annealing at different temperatures ranging from room temperature to 400 1C were also analyzed. The results indicate that the prepared AZO films exhibit highest ZnO (0 0 2) peak intensity and lowest electrical resistivity after annealing at 300 1C. And AZO film with a low resistivity value of 0.0185 Ω-cm, a relatively high average infrared reflection of 40% can be acquired after the films were annealed at 300 1C. The high infrared reflection property of the AZO film makes it a promising candidate for future heat shielding film.

Journal of Materials Science, 2011

ABSTRACT A novel modified Avrami model considering both primary and secondary crystallization has... more ABSTRACT A novel modified Avrami model considering both primary and secondary crystallization has been presented to extract the kinetic behavior of these two crystallization stages in nonisothermal crystallization process of polymers. Nonisothermal crystallization kinetics of poly(trimethylene terephthalate)–poly(ethylene glycol) segmented copolyesters (PTEG) has been investigated by differential scanning calorimetry. The crystallization rate constants and Avrami exponents at various cooling rates were obtained from the analyses for neat PTEG and multiwalled carbon nanotube (MWNT) filled PTEG. Secondary crystallization displays a lower-dimensional crystal growth compared with primary crystallization and the results of kinetics analyses are consistent with morphology study. The MWNTs introduced into PTEG matrix take the role of effective nucleating agents during composites crystallization and can expedite the process of crystallization of the matrix by providing more nucleation sites to the crystallizing phase.

Coloration Technology, 1999

The effect of the addition of metal ions to dye solutions in promoting dye aggregation and in cha... more The effect of the addition of metal ions to dye solutions in promoting dye aggregation and in changing dye association in solution has been studied. Experimental findings indicate that the promoting effects of calcium and magnesium ions are greater than that of sodium ions. It is expected that any change in dye hydrophobicity would have a direct influence on the extent of dye aggregation. Under acid conditions, a higher concentration of metal ions would result in an increase in dye aggregation with a reduction in dye hydrophobicity. On the other hand, while the dye aggregation is increased under alkaline conditions under the influence of metal ions, hydrophobicity was shown to increase. These changes in dye hydrophobicity could be used to explain the dyeing behaviour of reactive dyes in the dyeing of silk.

Carbohydrate Polymers, 2011

In this work, silk fibroin/cellulose (SF/CE) blend films were regenerated from hydrophilic ionic ... more In this work, silk fibroin/cellulose (SF/CE) blend films were regenerated from hydrophilic ionic liquid, 1-butyl-3-methylimidazolium chloride (BmimCl). The structure of the blend films was characterised by Fourier transform infrared spectroscopy (FTIR). The thermal and mechanical properties and the surface morphology of the blend films were also investigated. In addition, moisture content, swelling index, total water absorption and film weight loss were measured. The results indicate that with the introduction of CE, the interactions between SF and CE in the blend films induced the conformation transition of SF from random coil form or silk I to ␤-sheet structure. At the same time, the physical properties of the blend films were improved. When the ratio of SF to CE is 25:75, the stronger interactions in the matrices contribute to the higher tensile strength, higher thermal stability and higher water stability. However, the blend film with half CE illustrates higher elongation at break, a more homogeneous surface and higher miscibility.

Carbohydrate Polymers, 2013

Fabricating novel functional and structural materials from natural renewable and degradable mater... more Fabricating novel functional and structural materials from natural renewable and degradable materials has attracted much attention. Natural polysaccharides and proteins are the right natural candidates due to their unique structures and properties. The polysaccharide-protein composites or blends were widely investigated, however, there are few systematical studies on the interactions between natural polysaccharides and silk fibroin protein at the molecular level. Among various interactions, hydrogen bonding, electrostatic interactions and covalent bonding play important roles in the structure and properties of the corresponding materials. Therefore, the focus is placed on the three interactions types in this review. A future challenge is to create polysaccharide and protein composites or blends with tailored structure and properties for the wide applications.

Journal of Alloys and Compounds, 2014

Ceramics International, 2015

Polymer, Mar 10, 2011

Poly(9-(2-(4-vinyl(benzyloxy)ethyl)-9H-carbazole)) (PVBEC) brushes, have been successfully prepar... more Poly(9-(2-(4-vinyl(benzyloxy)ethyl)-9H-carbazole)) (PVBEC) brushes, have been successfully prepared on the silicon surfaces via surface-initiated atom transfer radical polymerization (ATRP). Conductance switching at a voltage of about À2.1 V is observed in the memory device based on the PVBEC brushes. The fabricated device shows the good memory characteristics as the ON/OFF current ratio up to 10 5 , and enduring 10 6 read cycles under À1 V pulse voltages. Compared with those of the conventional Si/PVBEC/ Al device fabricated by spin-coating, the switch voltage is lower and the ON/OFF current ratio is higher in the volatile Si-g-PVBEC/Al memory device.

Applied Surface Science, 2011

Nine polycarboxylic acids were used to improve washing durability of hydrophobic cellulose fabric... more Nine polycarboxylic acids were used to improve washing durability of hydrophobic cellulose fabric finished by sol–gel method. By simultaneous forming ester-bridge between cellulose and silica layer by ester bond, polycarboxylic acids could anchor silica coating onto cellulose fabric to strengthen the adhesion of organic–inorganic hybrid coating. The wettability of treated fabrics was characterized by water contact angle, spray test and hydrostatic pressure test. The results showed that all investigated polycarboxylic acids could improve the durability. The polycarboxylic acid with proper distance between terminal carboxylic acid groups and number of carboxylic acid groups showed the highest durability. 1,2,3,4-butanetetracarboxylic acid (BTCA) led to the best durability of hydrophobic cellulose fabric with water contact angle of 137.6° (recovery percentage of 94.2%) after 30 washing times. The effect of BTCA on durability was characterized by scanning electron microscopy. This study demonstrated that the surface treatment using polycarboxylic acids and mixed organosilanes is a promising alternative for achieving durable hydrophobic fabrics.

Research Journal of Textile and Apparel, 2011

Journal of Macromolecular Science, Part B, 2015

Organic Electronics, 2012

Polymer Testing, 2010

Poly(trimethylene terephthalate)-poly(ethylene glycol) segmented copolyester (PTEG)/ multi-walled... more Poly(trimethylene terephthalate)-poly(ethylene glycol) segmented copolyester (PTEG)/ multi-walled carbon nanotube (MWCNT) nanocomposites with various MWCNT content and copolyester composition were prepared by solution blending and the effect of MWCNTs on the crystallization behavior of PTEG copolymers was explored by differential scanning calorimetry (DSC), depolarized light intensity (DLI) technique and polarized light microscopy (PLM). The dynamic crystallization and the crystallization morphology of the nanocomposites are discussed. The isothermal crystallization kinetics was analyzed by means of a two stage crystallization kinetics model. The results showed that MWCNTs take the role of an effective nucleating agent during composite crystallization and can expedite the process of crystallization of the PTEG matrix by providing more nucleation sites to the crystallizing phase, which results in the formation of smaller spherulites.

Journal of Nanoparticle Research, Jun 4, 2012

Journal of Polymer Science Part B: Polymer Physics, 2016

Ceramics International, 2014

AZO/Ag/AZO trilayer films were prepared on glass substrates by radio frequency (RF) magnetron spu... more AZO/Ag/AZO trilayer films were prepared on glass substrates by radio frequency (RF) magnetron sputtering technology. Crystal structure, surface morphology, visible transmittance, and color scale of the AZO/Ag/AZO coated trilayers as functions of Ag and AZO layers thickness were investigated by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM), optical transmittance spectra and CIELAB system. In addition, the electrical and infrared reflection properties of the coated trilayers were examined by four-point probe system and Fourier Transform Infrared Spectroscopy. The results indicated that the Ag inner layer started forming a continuous film at the thickness of 10 nm which was supported by XRD result of the distinct 200 and 220 Ag peaks. Besides, the highest average visible transmittance of 80.5% was obtained by the AZO (30 nm)/Ag (10 nm)/AZO (30 nm) structure. Furthermore, the lowest sheet resistivity of 4.36 Ω/sq and the highest infrared reflection rate of 96% in FIR region can be obtained by the AZO (30 nm)/Ag (13 nm)/AZO (30 nm) structure. The high infrared reflection property of the AZO/Ag/AZO trilayers makes it a promising candidate for energy conservation coatings.

Ceramics International, 2015

Radio Frequency (RF) magnetron sputtered TiO 2 thin films have been deposited on flexible textile... more Radio Frequency (RF) magnetron sputtered TiO 2 thin films have been deposited on flexible textile substrates such as polyester and cotton fabrics, yielding a flexible composite architecture. The structure of the composites was systematically investigated by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Contact Angle tester. The deposited TiO 2 thin films featured unique high porosity and amorphous structure which combined with the flexibility of the textile base show promise for photovoltaic applications.

Ceramics International, 2015

ABSTRACT Ag and AZO/Ag/AZO ceramic films were deposited on cotton fabrics by radio frequency (RF)... more ABSTRACT Ag and AZO/Ag/AZO ceramic films were deposited on cotton fabrics by radio frequency (RF) magnetron sputtering and systematically investigated by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy. Physical properties of the coated fabrics were evaluated by infrared reflection rate, air permeability and UPF value. Ag coated cotton fabrics presented an infrared reflection rate of 16% and the highest UPF values of 11.096. The AZO/Ag/AZO coated cotton fabrics exhibited an infrared reflection rate of 18% and the highest UPF values of 21.782. The prepared flexible cotton fabrics can provide UV radiation protection and infrared reflective properties, which make them promising materials for solar control applications.

Vacuum, 2014

a b s t r a c t AZO/Ag/AZO multilayer films were prepared on PET substrate by radio frequency (RF... more a b s t r a c t AZO/Ag/AZO multilayer films were prepared on PET substrate by radio frequency (RF) magnetron sputtering technology. The prepared films were investigated by optical transmittance spectra, a fourpoint probe system, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Atomic Force Microscopy (AFM), and Fourier Transform Infrared Spectroscopy. The results indicate that Ag inner layer starts forming a continuous film at the thickness about 10 nm. The sample with 10 nm's Ag inner layer exhibited the highest average visible transmittance of 78.5% and 91%'s infrared reflection rate in FIR region. Sample with 15 nm's Ag inner layer showed the highest infrared reflection rate of 96% in FIR region. The high visible transmittance and infrared reflection property of the AZO/Ag/AZO multilayer film makes it a promising candidate for solar films.

Solar Energy Materials and Solar Cells, 2014

Al-doped ZnO (AZO) films were prepared on glass substrates by radio frequency (RF) magnetron sput... more Al-doped ZnO (AZO) films were prepared on glass substrates by radio frequency (RF) magnetron sputtering technology. Crystal structure, surface morphology, electrical properties and infrared reflection of the AZO films were systematically investigated by X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), Hall measurement system and Fourier Transform infrared spectroscopy, respectively. In addition, the corresponding properties of AZO films annealing at different temperatures ranging from room temperature to 400 1C were also analyzed. The results indicate that the prepared AZO films exhibit highest ZnO (0 0 2) peak intensity and lowest electrical resistivity after annealing at 300 1C. And AZO film with a low resistivity value of 0.0185 Ω-cm, a relatively high average infrared reflection of 40% can be acquired after the films were annealed at 300 1C. The high infrared reflection property of the AZO film makes it a promising candidate for future heat shielding film.

Journal of Materials Science, 2011

ABSTRACT A novel modified Avrami model considering both primary and secondary crystallization has... more ABSTRACT A novel modified Avrami model considering both primary and secondary crystallization has been presented to extract the kinetic behavior of these two crystallization stages in nonisothermal crystallization process of polymers. Nonisothermal crystallization kinetics of poly(trimethylene terephthalate)–poly(ethylene glycol) segmented copolyesters (PTEG) has been investigated by differential scanning calorimetry. The crystallization rate constants and Avrami exponents at various cooling rates were obtained from the analyses for neat PTEG and multiwalled carbon nanotube (MWNT) filled PTEG. Secondary crystallization displays a lower-dimensional crystal growth compared with primary crystallization and the results of kinetics analyses are consistent with morphology study. The MWNTs introduced into PTEG matrix take the role of effective nucleating agents during composites crystallization and can expedite the process of crystallization of the matrix by providing more nucleation sites to the crystallizing phase.

Coloration Technology, 1999

The effect of the addition of metal ions to dye solutions in promoting dye aggregation and in cha... more The effect of the addition of metal ions to dye solutions in promoting dye aggregation and in changing dye association in solution has been studied. Experimental findings indicate that the promoting effects of calcium and magnesium ions are greater than that of sodium ions. It is expected that any change in dye hydrophobicity would have a direct influence on the extent of dye aggregation. Under acid conditions, a higher concentration of metal ions would result in an increase in dye aggregation with a reduction in dye hydrophobicity. On the other hand, while the dye aggregation is increased under alkaline conditions under the influence of metal ions, hydrophobicity was shown to increase. These changes in dye hydrophobicity could be used to explain the dyeing behaviour of reactive dyes in the dyeing of silk.

Carbohydrate Polymers, 2011

In this work, silk fibroin/cellulose (SF/CE) blend films were regenerated from hydrophilic ionic ... more In this work, silk fibroin/cellulose (SF/CE) blend films were regenerated from hydrophilic ionic liquid, 1-butyl-3-methylimidazolium chloride (BmimCl). The structure of the blend films was characterised by Fourier transform infrared spectroscopy (FTIR). The thermal and mechanical properties and the surface morphology of the blend films were also investigated. In addition, moisture content, swelling index, total water absorption and film weight loss were measured. The results indicate that with the introduction of CE, the interactions between SF and CE in the blend films induced the conformation transition of SF from random coil form or silk I to ␤-sheet structure. At the same time, the physical properties of the blend films were improved. When the ratio of SF to CE is 25:75, the stronger interactions in the matrices contribute to the higher tensile strength, higher thermal stability and higher water stability. However, the blend film with half CE illustrates higher elongation at break, a more homogeneous surface and higher miscibility.

Carbohydrate Polymers, 2013

Fabricating novel functional and structural materials from natural renewable and degradable mater... more Fabricating novel functional and structural materials from natural renewable and degradable materials has attracted much attention. Natural polysaccharides and proteins are the right natural candidates due to their unique structures and properties. The polysaccharide-protein composites or blends were widely investigated, however, there are few systematical studies on the interactions between natural polysaccharides and silk fibroin protein at the molecular level. Among various interactions, hydrogen bonding, electrostatic interactions and covalent bonding play important roles in the structure and properties of the corresponding materials. Therefore, the focus is placed on the three interactions types in this review. A future challenge is to create polysaccharide and protein composites or blends with tailored structure and properties for the wide applications.

Journal of Alloys and Compounds, 2014

Ceramics International, 2015

Polymer, Mar 10, 2011

Poly(9-(2-(4-vinyl(benzyloxy)ethyl)-9H-carbazole)) (PVBEC) brushes, have been successfully prepar... more Poly(9-(2-(4-vinyl(benzyloxy)ethyl)-9H-carbazole)) (PVBEC) brushes, have been successfully prepared on the silicon surfaces via surface-initiated atom transfer radical polymerization (ATRP). Conductance switching at a voltage of about À2.1 V is observed in the memory device based on the PVBEC brushes. The fabricated device shows the good memory characteristics as the ON/OFF current ratio up to 10 5 , and enduring 10 6 read cycles under À1 V pulse voltages. Compared with those of the conventional Si/PVBEC/ Al device fabricated by spin-coating, the switch voltage is lower and the ON/OFF current ratio is higher in the volatile Si-g-PVBEC/Al memory device.