Adhesion of polyethylene plates photografted with methacrylic acid and acrylic acid with enzymatically modified chitosan solutions and X-ray photoelectron spectroscopy analysis of failed surfaces

2011 ◽  
Vol 121 (2) ◽  
pp. 939-950 ◽  
Author(s):  
Sho Yamagami ◽  
Wataru Kanama ◽  
Kazunori Yamada
2021 ◽  
Author(s):  
Yi-Fang Lee ◽  
Tzong-Ming Wu

Abstract A set of novel biocompatible aliphatic-aromatic nanocomposites, including numerous acrylic acid-grafted poly(butylene carbonate-co-terephthalate) (g-PBCT) and organically-modified layered zinc phenylphosphonate (m-PPZn), were successfully synthesized via polycondensation and transesterification. A primary covalent linkage was produced between the biocompatible polymer and the inorganic reinforcements. Fourier transform infrared spectroscopy and 13C-nuclear magnetic resonance spectra demonstrated the successful grafting of acrylic acid into the PBCT (g-PBCT). Both wide-angle X-ray diffraction data and X-ray photoelectron spectroscopy analysis showed that the g-PBCT polymer matrix was intercalated into the interlayer spacing of the m-PPZn and was chemically interacted with the m-PPZn. The addition of m-PPZn in the g-PBCT matrix significantly improved its storage modulus. A slight increase in thermal stability was observed in all the g-PBCT/m-PPZn composites. Both results are attributed to the presence of covalent bond between g-PBCT and m-PPZn.


2011 ◽  
Vol 396-398 ◽  
pp. 586-591
Author(s):  
He Lin Hua ◽  
Jun Chao Zhang ◽  
Na Li ◽  
Li An Wei

The copolymers of polysulfone-graft-acrylic (PSF-g-PAAc) acid were synthesized by homogeneous photo-initiated graft copolymerization method. Variable affecting the degree of grafting (DG), such as the ultraviolet irradiation time, and the concentrations of the acrylic acid monomer and photoinitiator, were investigated. The graft copolymers were characterized by chemical titration, attenuated total reflection-Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy analysis. It is verified that acrylic acid groups were present on the polysulfone polymer. Then, membranes were prepared from the PSF-g-PAAc powder with different DG using phase inversion method. It is found that the flux properties of the membranes were dependent on the pH value of the aqueous solution.


2017 ◽  
Vol 31 (5) ◽  
pp. 657-667 ◽  
Author(s):  
S Varnagiris ◽  
S Tuckute ◽  
M Lelis ◽  
D Milcius

Currently, polymeric insulation materials are widely used for energy saving in buildings. Despite of all benefits, these materials are generally sensitive to heat and highly flammable. This work discusses possibility to improve heat resistance of expanded polystyrene (EPS) foam using thin silicon dioxide (SiO2) films deposited by magnetron sputtering technique. In order to increase surface energy and adherence of SiO2 thin films to substrate EPS was plasma pretreated before films’ depositions using pulsed DC plasma generator for 40 s in argon gas. SiO2 formation was done in reactive argon and oxygen gas atmosphere. Laboratory made equipment was used for flame torch–induced heat resistance experiments. Results showed that silicon oxide films remains stable during heat resistance experiments up to 5 s and fully protects polystyrene (PS) substrate. Films are relatively stable for 30 s and 60 s and partially protect PS from melting and ignition. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy analysis confirmed that SiO2 layer, which is distributed uniformly on the EPS surface, could work as a good heat resistant material.


Minerals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1377
Author(s):  
Yuki Semoto ◽  
Gde Pandhe Wisnu Suyantara ◽  
Hajime Miki ◽  
Keiko Sasaki ◽  
Tsuyoshi Hirajima ◽  
...  

Sodium metabisulfite (MBS) was used in this study for selective flotation of chalcopyrite and molybdenite. Microflotation tests of single and mixed minerals were performed to assess the floatability of chalcopyrite and molybdenite. The results of microflotation of single minerals showed that MBS treatment significantly depressed the floatability of chalcopyrite and slightly reduced the floatability of molybdenite. The results of microflotation of mixed minerals demonstrated that the MBS treatment could be used as a selective chalcopyrite depressant in the selective flotation of chalcopyrite and molybdenite. Furthermore, the addition of diesel oil or kerosene could significantly improve the separation efficiency of selective flotation of chalcopyrite and molybdenite using MBS treatment. A mechanism based on X-ray photoelectron spectroscopy analysis results is proposed in this study to explain the selective depressing effect of MBS on the flotation of chalcopyrite and molybdenite.


Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1417 ◽  
Author(s):  
Wang ◽  
Xiao ◽  
Huang ◽  
Zheng ◽  
Luo ◽  
...  

Chitosan microspheres modified by 2-pyridinecarboxaldehyde were prepared and used in the construction of a heterogeneous catalyst loaded with nano-Cu prepared by a reduction reaction. The chemical structure of the catalyst was investigated by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). Under mild conditions, such as no ligand at room temperature, the catalyst was successfully applied to catalyze the borylation of α,β-unsaturated receptors in a water-methanol medium, yielding 17%–100% of the corresponding -hydroxy product. Even after repeated use five times, the catalyst still exhibited excellent catalytic activity.


2018 ◽  
Vol 145 ◽  
pp. 50-53 ◽  
Author(s):  
Iraida N. Demchenko ◽  
Yevgen Syryanyy ◽  
Yevgen Melikhov ◽  
Laurent Nittler ◽  
Leszek Gladczuk ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document