Porous membranes based on poly(ether imide)-graft-poly(vinyl acetate) as a scaffold for cell growth

2017 ◽  
Vol 33 (2) ◽  
pp. 178-194 ◽  
Author(s):  
Bin Liu ◽  
Jiangying Kuang ◽  
Leishan Shao ◽  
Xinyuan Che ◽  
Fei Wang ◽  
...  

A series of poly(ether imide)-graft-poly(vinyl acetate) copolymers with different molecular weights were synthesized successfully and characterized using Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, proton nuclear magnetic resonance, gel permeation chromatography, differential scanning calorimeter, thermogravimetric analysis, and X-ray photoelectron spectroscopy analyses. These copolymers were used to fabricate honeycomb-structured porous films using the breath figure templating technique. The surface topology and composition of the highly ordered pattern film were further characterized using a scanning electron microscopy. The results indicated that the poly(ether imide)-graft-poly(vinyl acetate) graft molecular weight ratio influenced the breath figure film surface topology. A model was proposed to elucidate the stabilization process of the poly(ether imide)-graft-poly(vinyl acetate)-aggregated architecture on the water droplet–based templates. In addition, cell viability has been investigated via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test, and the cell morphology on the honeycomb-structured poly(ether imide)-graft-poly(vinyl acetate) porous film has been evaluated using a fluorescence microscope. This porous film is shown to be suitable as a matrix for cell growth.

2021 ◽  
Author(s):  
Pengcheng Cui ◽  
Silong Wu ◽  
Jun Xie ◽  
Jiaying Ma ◽  
Lingyun Ding ◽  
...  

Asymmetric multi-layered porous film was prepared by casting inverse emulsion following the breath figure method. The porous morphologies both on the surface and in the bulk of the fabricated film...


2012 ◽  
Vol 496 ◽  
pp. 138-141 ◽  
Author(s):  
Wen Yong Liu ◽  
Yi Chen ◽  
Yue Jun Liu ◽  
Xi Hai Hao

We investigated the preparation of porous film of cellulose-based graft copolymer by breath figure method. The effects of substrate, solvent, graft density and graft length on the formation of porous film were elucidated. The results showed that ordered porous films could be facilely formed on the glass and mica substrate, while no ordered porous films were obtained on the silicon substrate. The ordered porous films were formed from the copolymer/CS2 solution, while no ordered porous films were done from the copolymer/CH2Cl2, CHCl3 and toluene solution. Moreover, no ordered porous films were obtained from the copolymer with spare graft density or with long side chain. The results indicated that the substrate, solvent, graft density and graft length had important effects on the ordered porous film.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marla V. V. Satya Aditya ◽  
Srikanta Panda ◽  
Sankara Sarma V. Tatiparti

AbstractHydrogen uptake (H-uptake) is studied in ball milled Mg-B-electrochemically synthesized reduced graphene oxide (erGO) nanocomposites at PH2 ≈ 15 bar, ~ 320 °C. B/C (weight ratio): 0, ~ 0.09, ~ 0.36, ~ 0.90 are synthesized maintaining erGO≈10wt %. B occupies octahedral interstices within Mg unit cell—revealed by electron density maps. Persistent charge donations from Mg and B to C appear as Mg-C (~ 283.2 eV), B-C (~ 283.3–283.9 eV) interactions in C-1s core X-ray photoelectron spectroscopy (XPS) at all B/C. At B/C > 0.09, charge reception by B from Mg yields Mg-B interaction. This net charge acceptor role of B renders it electron-rich and does not alter Mg unit cell size significantly. Despite charge donation to both C and B, the Mg charge is <  + 2, resulting in long incubation times (> 5 h) at B/C > 0.09. At B/C≈0.09 the minimal Mg-B interaction renders B a charge donor, resulting in Mg-B repulsion and Mg unit cell expansion. Mg-C peak shift to lower binding energies (C-1s XPS), decreases incubation time to ~ 2.25 h and enhances H-uptake kinetics. Various atomic interactions influence the reduction of incubation time in H-uptake and increase its kinetics in the order: (Mg → C; B → C)B/C≈0.09, B: donor > (Mg → C)B/C=0 > (ternary Mg → B → C)B/C>0.09, B: acceptor.


2021 ◽  
Vol 11 (15) ◽  
pp. 6675
Author(s):  
Tran Si Trong Khanh ◽  
Tran Quang Trung ◽  
Le Thuy Thanh Giang ◽  
Tran Quang Nguyen ◽  
Nguyen Dinh Lam ◽  
...  

In this work, the P3HT:rGO:MWCNTs (PGC) nanocomposite film applied to the ammonia gas sensor was successfully fabricated by a drop-casting technique. The results demonstrated that the optimum weight ratio of the PGC nanocomposite gas sensor is 20%:60%:20% as the weight ratio of P3HT:rGO:MWCNTs (called PGC-60). This weight ratio leads to the formation of nanostructured composites, causing the efficient adsorption/desorption of ammonia gas in/out of the film surface. The sensor based on PGC-60 possessed a response time of 30 s, sensitivity up to 3.6% at ammonia gas concentration of 10 ppm, and relative sensitivity of 0.031%/ppm. These results could be attributed to excellent electron transportation of rGO, the main adsorption activator to NH3 gas of P3HT, and holes move from P3HT to the cathodes, which works as charge “nano-bridges” carriers of Multi-Walled Carbon Nanotubes (MWCNTs). In general, these three components of PGC sensors have significantly contributed to the improvement of both the sensitivity and response time in the NH3 gas sensor.


Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3191
Author(s):  
Arun Kumar Mukhopadhyay ◽  
Avishek Roy ◽  
Gourab Bhattacharjee ◽  
Sadhan Chandra Das ◽  
Abhijit Majumdar ◽  
...  

We report the surface stoichiometry of Tix-CuyNz thin film as a function of film depth. Films are deposited by high power impulse (HiPIMS) and DC magnetron sputtering (DCMS). The composition of Ti, Cu, and N in the deposited film is investigated by X-ray photoelectron spectroscopy (XPS). At a larger depth, the relative composition of Cu and Ti in the film is increased compared to the surface. The amount of adventitious carbon which is present on the film surface strongly decreases with film depth. Deposited films also contain a significant amount of oxygen whose origin is not fully clear. Grazing incidence X-ray diffraction (GIXD) shows a Cu3N phase on the surface, while transmission electron microscopy (TEM) indicates a polycrystalline structure and the presence of a Ti3CuN phase.


2002 ◽  
Vol 750 ◽  
Author(s):  
Yoshifumi Aoi ◽  
Kojiro Ono ◽  
Kunio Sakurada ◽  
Eiji Kamijo

ABSTRACTAmorphous CNx thin films were deposited by pulsed laser deposition (PLD) combined with a nitrogen rf radical beam source which supplies active nitrogen species to the growing film surface. The deposited films were characterized by X-ray photoelectron spectroscopy (XPS), Raman scattering, and Fourier transform infrared (FTIR) spectroscopy. Nitrogen content of the deposited films increased with increasing rf input power and N2 pressure in the PLD chamber. The maximum N/C ratio 0.23 was obtained at 400 W of rf input power and 1.3 Pa. XPS N 1s spectra shows the existence of several bonding structures in the deposited films. Electrical properties of the deposited films were investigated. The electrical conductivity decreased with increasing N/C atomic ratio. Temperature dependence of electrical conductivity measurements indicated that electronic conduction occurred by variable-range hopping between p electron localized states.


Polymers ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 979 ◽  
Author(s):  
Chunfang Zhu ◽  
Haitao Yang ◽  
Hongbo Liang ◽  
Zhengyue Wang ◽  
Jun Dong ◽  
...  

Low surface energy materials have attracted much attention due to their properties and various applications. In this work, we synthesized and characterized a series of ultraviolet (UV)-curable fluorinated siloxane polymers with various fluorinated acrylates—hexafluorobutyl acrylate, dodecafluoroheptyl acrylate, and trifluorooctyl methacrylate—grafted onto a hydrogen-containing poly(dimethylsiloxane) backbone. The structures of the fluorinated siloxane polymers were measured and confirmed by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy. Then the polymers were used as surface modifiers of UV-curable commercial polyurethane (DR-U356) at different concentrations (1, 2, 3, 4, 5, and 10 wt %). Among three formulations of these fluorinated siloxane polymers modified with DR-U356, hydrophobic states (91°, 92°, and 98°) were obtained at low concentrations (1 wt %). The DR-U356 resin is only in the hydrophilic state at 59.41°. The fluorine and siloxane element contents were investigated by X-ray photoelectron spectroscopy and the results indicated that the fluorinated and siloxane elements were liable to migrate to the surface of resins. The results of the friction recovering assays showed that the recorded contact angles of the series of fluorinated siloxane resins were higher than the original values after the friction-annealing progressing.


Nanomaterials ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1458 ◽  
Author(s):  
Leon-Ramos ◽  
Diosdado-Cano ◽  
López-Santos ◽  
Barranco ◽  
Torres-Lagares ◽  
...  

Aim: Titanium implants are commonly used as replacement therapy for lost teeth and much current research is focusing on the improvement of the chemical and physical properties of their surfaces in order to improve the osseointegration process. TiO2, when it is deposited in the form of pillar array nanometric structures, has photocatalytic properties and wet surface control, which, together with UV irradiation, provide it with superhydrophilic surfaces, which may be of interest for improving cell adhesion on the peri-implant surface. In this article, we address the influence of this type of surface treatment on type IV and type V titanium discs on their surface energy and cell growth on them. Materials and methods: Samples from titanium rods used for making dental implants were used. There were two types of samples: grade IV and grade V. In turn, within each grade, two types of samples were differentiated: untreated and treated with sand blasting and subjected to double acid etching. Synthesis of the film consisting of titanium oxide pillar array structures was carried out using plasma-enhanced chemical vapor deposition equipment. The plasma was generated in a quartz vessel by an external SLAN-1 microwave source with a frequency of 2.45 GHz. Five specimens from each group were used (40 discs in total). On the surfaces to be studied, the following determinations were carried out: (a) X-ray photoelectron spectroscopy, (b) scanning electron microscopy, (c) energy dispersive X-ray spectroscopy, (d) profilometry, (e) contact angle measurement or surface wettability, (f) progression of contact angle on applying ultraviolet irradiation, and (g) a biocompatibility test and cytotoxicity with cell cultures. Results: The application of ultraviolet light decreased the hydrophobicity of all the surfaces studied, although it did so to a greater extent on the surfaces with the studied modification applied, this being more evident in samples manufactured in grade V titanium. In samples made in grade IV titanium, this difference was less evident, and even in the sample manufactured with grade IV and SLA treatment, the application of the nanometric modification of the surface made the surface optically less active. Regarding cell growth, all the surfaces studied, grouped in relation to the presence or not of the nanometric treatment, showed similar growth. Conclusions. Treatment of titanium oxide surfaces with ultraviolet irradiation made them change temporarily into superhydrophilic ones, which confirms that their biocompatibility could be improved in this way, or at least be maintained.


Materials ◽  
2018 ◽  
Vol 11 (4) ◽  
pp. 481 ◽  
Author(s):  
Hua Yuan ◽  
Bing Yu ◽  
Hailin Cong ◽  
Ming Chi ◽  
Yuanzhe Cheng ◽  
...  

RSC Advances ◽  
2015 ◽  
Vol 5 (10) ◽  
pp. 7090-7097 ◽  
Author(s):  
Yang Xue ◽  
Shuang-Shuang Zhang ◽  
Kun Cui ◽  
Jin Huang ◽  
Qiao-Ling Zhao ◽  
...  

Polymethylene-based AB2 star copolymers were synthesized. PM-b-(PS)2 porous films and particles were fabricated via static breath-figure process and electrospraying, respectively.


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