Functional Properties of Polyurethane Ureteral Stents with PLGA and Papaverine Hydrochloride Coating

Despite the obvious benefits of using ureteral stents to drain the ureters, there is also a risk of complications from 80–90%. The presence of a foreign body in the human body causes disturbances in its proper functioning. It can lead to biofilm formation on the stent surface, which may favor the development of urinary tract infections or the formation of encrustation, as well as stent fragmentation, complicating its subsequent removal. In this work, the effect of the polymeric coating containing the active substance-papaverine hydrochloride on the functional properties of ureteral stents significant for clinical practice were assessed. Methods: The most commonly clinically used polyurethane ureteral Double-J stent was selected for the study. Using the dip-coating method, the surface of the stent was coated with a poly(D,L-lactide-glycolide) (PLGA) coating containing the papaverine hydrochloride (PAP). In particular, strength properties, retention strength of the stent ends, dynamic frictional force, and the fluoroscopic visibility of the stent during X-ray imaging were determined. Results: The analysis of the test results indicates the usefulness of a biodegradable polymer coating containing the active substance for the modification of the surface of polyurethane ureteral stents. The stents coated with PLGA+PAP coating compared to polyurethane stents are characterized by more favorable strength properties, the smaller value of the dynamic frictional force, without reducing the fluoroscopic visibility.

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Porous Gel Coatings Obtained by Phase Separation in ORMOSIL System

MRS Proceedings ◽

10.1557/proc-628-cc7.6 ◽

2000 ◽

Vol 628 ◽

Cited By ~ 1

Author(s):

Kazuki Nakanishi ◽

Souichi Kumon ◽

Kazuyuki Hirao ◽

Hiroshi Jinnai

Keyword(s):

Phase Separation ◽

Reaction Time ◽

Volume Fraction ◽

Sol Gel ◽

Reaction Times ◽

Dip Coating ◽

Coating Solution ◽

Coating Method ◽

Gel Phase ◽

Dip Coating Method

ABSTRACTMacroporous silicate thick films were prepared by a sol-gel dip-coating method accompanied by the phase separation using methyl-trimethoxysilane (MTMS), nitric acid and dimethylformamide (DMF) as starting components. The morphology of the film varied to a large extent depending on the time elapsed after the hydrolysis until the dipping of the coating solution. On a glass substrate, the films prepared by early dipping had inhomogeneous submicrometer-sized pores on the surface of the film. At increased reaction times, relatively narrow sized isolated macropores were observed and their size gradually decreased with the increase of reaction time. On a polyester substrate, in contrast, micrometer-sized isolated spherical gel domains were homogeneously deposited by earlier dippings. With an increase of reaction time, the volume fraction of the gel phase increased, then the morphology of the coating transformed into co-continuous gel domains and macropores, and finally inverted into the continuous gel domains with isolated macropores. The overall morphological variation with the reaction time was explained in terms of the phase separation and the structure freezing by the forced gelation, both of which were induced by the evaporation of methanol during the dipping operation.

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PREPARATION AND CHARACTERIZATION OF POLYVINYL ALCOHOL THIN FILMS FOR ORGANIC THIN FILM TRANSISTORS AND BIOMEDICAL APPLICATIONS

Kongunadu Research Journal ◽

10.26524/krj264 ◽

2018 ◽

Vol 5 (2) ◽

pp. 16-18

Author(s):

Chandar Shekar B ◽

Ranjit Kumar R ◽

Dinesh K.P.B ◽

Sulana Sundar C ◽

Sunnitha S ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Thin Film Transistors ◽

Gravimetric Method ◽

Dip Coating ◽

Organic Thin Film Transistors ◽

Poly Vinyl Alcohol ◽

Organic Thin Film ◽

Glass Substrates ◽

Coating Method

Thin films of poly vinyl alcohol (PVA) were prepared on pre-cleaned glass substrates by Dip Coating Method. FTIR spectrum was used to identify the functional groups present in the prepared films. The vibrational peaks observed at 1260 cm-1 and 851 cm-1 are assigned to C–C stretching and CH rocking of PVA.The characteristic band appearing at 1432 cm-1 is assigned to C–H bend of CH2 of PVA. The thickness of the prepared thin films were measured by using an electronic thickness measuring instrument (Tesatronic-TTD20) and cross checked by gravimetric method. XRD spectra indicated the amorphous nature of the films.Surface morphology of the coated films was studied by scanning electron microscope (SEM). The surface revealed no pits and pin holes on the surface. The observed surface morphology indicated that these films could be used as dielectric layer in organic thin film transistors and as drug delivery system for wound healing.

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Preparation of Polypropylene/PVDF Composite Membrane by Dip-Coating Method

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1115/1/012028 ◽

2021 ◽

Vol 1115 (1) ◽

pp. 012028

Author(s):

P T P Aryanti ◽

G Trilaksono ◽

A Hotmaida ◽

M A Afifah ◽

F P Pratiwi ◽

...

Keyword(s):

Composite Membrane ◽

Dip Coating ◽

Coating Method ◽

Dip Coating Method

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Heat Scanning for the Fabrication of Conductive Fibers

Polymers ◽

10.3390/polym13091405 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1405

Author(s):

Jina Jang ◽

Haoyu Zhou ◽

Jungbae Lee ◽

Hakgae Kim ◽

Jung Bin In

Keyword(s):

Silver Nanowires ◽

Building Blocks ◽

Dip Coating ◽

Coating Materials ◽

Scanning Time ◽

Silver Ink ◽

Nylon Fiber ◽

Coating Method ◽

Conductive Fibers ◽

Tubular Heater

Conductive fibers are essential building blocks for implementing various functionalities in a textile platform that is highly conformable to mechanical deformation. In this study, two major techniques were developed to fabricate silver-deposited conductive fibers. First, a droplet-coating method was adopted to coat a nylon fiber with silver nanoparticles (AgNPs) and silver nanowires (AgNWs). While conventional dip coating uses a large ink pool and thus wastes coating materials, droplet-coating uses minimal quantities of silver ink by translating a small ink droplet along the nylon fiber. Secondly, the silver-deposited fiber was annealed by similarly translating a tubular heater along the fiber to induce sintering of the AgNPs and AgNWs. This heat-scanning motion avoids excessive heating and subsequent thermal damage to the nylon fiber. The effects of heat-scanning time and heater power on the fiber conductance were systematically investigated. A conductive fiber with a resistance as low as ~2.8 Ω/cm (0.25 Ω/sq) can be produced. Finally, it was demonstrated that the conductive fibers can be applied in force sensors and flexible interconnectors.

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Characterization of UHMWPE- HAp coating produced by dip coating method on Ti6Al4V alloy

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2021.127091 ◽

2021 ◽

pp. 127091

Author(s):

Gözde Çelebi Efe ◽

Elif Yenilmez ◽

İbrahim Altinsoy ◽

Serbülent Türk ◽

Cuma Bindal

Keyword(s):

Dip Coating ◽

Ti6al4v Alloy ◽

Coating Method ◽

Dip Coating Method

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Effect of annealing temperature on structural and optical properties of nickel oxide thin films by dip coating method

10.1063/5.0029961 ◽

2020 ◽

Author(s):

Latha Jithendrakumar Meenakshi ◽

Balakrishnan Remani Aswathy ◽

Poonthamannil Karunakarapanicker Manoj

Keyword(s):

Thin Films ◽

Optical Properties ◽

Nickel Oxide ◽

Annealing Temperature ◽

Dip Coating ◽

Oxide Thin Films ◽

Structural And Optical Properties ◽

Coating Method ◽

Dip Coating Method ◽

Nickel Oxide Thin Films

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The Effect of Film Thickness and Content on Film Formation from PS/ Nanocomposites Prepared by Dip-Coating Method

Journal of Nanomaterials ◽

10.1155/2012/524343 ◽

2012 ◽

Vol 2012 ◽

pp. 1-17 ◽

Cited By ~ 3

Author(s):

M. Selin Sunay ◽

Onder Pekcan ◽

Saziye Ugur

Keyword(s):

Film Thickness ◽

Elevated Temperatures ◽

Film Formation ◽

Fluorescence Emission ◽

Dip Coating ◽

Atomic Force ◽

Annealing Step ◽

Coating Method ◽

Fluorescence Emission Intensity ◽

Dip Coating Method

Steady-state fluorescence (SSF) technique in conjunction with UV-visible (UVV) technique and atomic force microscope (AFM) was used for studying film formation from TiO2covered nanosized polystyrene (PS) latex particles (320 nm). The effects of film thickness and TiO2content on the film formation and structure properties of PS/TiO2composites were studied. For this purpose, two different sets of PS films with thicknesses of 5 and 20 μm were prepared from pyrene-(P-) labeled PS particles and covered with various layers of TiO2using dip-coating method. These films were then annealed at elevated temperatures above glass transition temperature () of PS in the range of 100–280°C. Fluorescence emission intensity, from P and transmitted light intensity, were measured after each annealing step to monitor the stages of film formation. The results showed that film formation from PS latexes occurs on the top surface of PS/TiO2composites and thus developed independent of TiO2content for both film sets. But the surface morphology of the films was found to vary with both TiO2content and film thickness. After removal of PS, thin films provide a quite ordered porous structure while thick films showed nonporous structure.

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Preparation and properties of polyurethane coatings modified by polysilazane

High Performance Polymers ◽

10.1177/0954008319891758 ◽

2019 ◽

Vol 32 (6) ◽

pp. 611-619 ◽

Cited By ~ 1

Author(s):

Xiaoli Liu ◽

Zhen Ge ◽

Wenguo Zhang ◽

Yunjun Luo

Keyword(s):

Mechanical Property ◽

Photoelectron Spectroscopy ◽

Composite Coatings ◽

Composite Films ◽

Dip Coating ◽

Water Contact ◽

Research Attention ◽

Elongation At Break ◽

Coating Method ◽

Dip Coating Method

Due to their unique physicochemical properties, polysilazanes exhibit excellent performance when combined with some resin matrixes, which had drawn great research attention. In this article, polyurethane (PU) was firstly prepared by polytetrahydrofuran glycol, isophorone diisocyanate, and 1,4-butanediol as main materials. Then, the prepared PU was blended with polysilazane by mixing the two solutions together, which was cured to films via dip-coating method at room temperature. The structure, thermal stability, and surface properties of the composite coatings were investigated by Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and X-ray photoelectron spectroscopy. The results demonstrated that after modification with polysilazane, the heat resistance, hydrophobicity, and mechanical property of the PU coatings were improved. When the content of polysilazane was 6 wt%, the mechanical property of the composite films was optimized, with a maximum tensile strength of 25.7 MPa and elongation at break of 797%. Meanwhile, the water contact angle of the composite film was 107° and the water absorption reached a minimum of 2.1%, which showed improved hydrophobicity and water resistance.

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