Search results for "Polyurethane"
showing 5 items of 65 documents
Influence of Nanoclay Additive on Mechanical Properties of Bio-Based Polyurethane Nanocomposites
2013
This paper is about investigation of the bio-based polyurethanes from the rapeseed oil polyols and their modification with montmorillonite nanoparticles. The results of hardness and tensile properties investigation of polyurethane / montmorillonite nanocomposites are presented.
Topochemische reaktionen von monomeren mit konjugierten dreifachbindungen. II. Mitt.: Eine topochemische farb- und vernetzungsreaktion bei polymeren …
1970
Es wurden kristallisationsfahige Polymere mit zwei konjugierten CC-Dreifachbindungen im Grundbaustein hergestellt und ihre Reaktionsfahigkeit im kristallinen Zustand untersucht. Die Polyurethane aus 2.4-Hexadiin-1.6-diol (I) bzw. 3.6.13.16-Tetraoxa-octadeca-8.10-diin-1.18-diol (II) und Hexamethylendiisocyanat sowie der Polyester aus I und Adipoylchlorid farben sich beim Belichten mit UV-Licht oder beim Tempern unterhalb ihres Schmelzpunktes tief rot und werden dabei unloslich. Die Reaktion kann durch Radikaldonatoren katalysiert und durch Radikalfanger inhibiert werden. Die gelosten Polymeren zeigen keine Reaktivitat in dieser Hinsicht. Die Verfarbung und Vernetzungsreaktion kann in Analogi…
Polytetrafluoroethylene Films in Rigid Polyurethane Foams' Dielectric Permittivity Measurements with a One-Side Access Capacitive Sensor.
2021
As a non-metallic composite material, widely applied in industry, rigid polyurethane (PUR) foams require knowledge of their dielectric properties. In experimental determination of PUR foams’ dielectric properties protection of one-side capacitive sensor’s active area from adverse effects caused by the PUR foams’ test objects has to be ensured. In the given study, the impact of polytetrafluoroethylene (PTFE) films, thickness 0.20 mm and 0.04 mm, in covering or simulated coating the active area of one-side access capacitive sensor’ electrodes on the experimentally determined true dielectric permittivity spectra of rigid PUR foams is estimated. Penetration depth of the low frequency excitation…
Dressings and Securement Devices of Peripheral Arterial Catheters in Intensive Care Units and Operating Theaters
2020
Background: Hemodynamic monitoring, implemented by the placement of peripheral arterial catheters (PACs), is a characterizing aspect of the intensive care units. Peripheral arterial catheters can continually detect blood pressure and quickly conduct blood sampling. The use of PACs is generally considered safe, without serious complications. Currently, only 25% of the implanted catheters are actually subject to complications, including accidental removal, dislocation, occlusion, and infection. All of these complications arise from inadequate catheter stabilization at the level of the skin. This study aimed to summarize and describe the effectiveness and characteristics of dressings and secur…
Encapsulation of AgNPs in a Lignin Isocyanate Film : Characterization and Antimicrobial Properties
2023
Lignin isolated from agricultural residues is a promising alternative for petroleum-based polymers as feedstocks in development of antimicrobial materials. A polymer blend based on silver nanoparticles and lignin–toluene diisocyanate film (AgNPs–Lg–TDIs) was generated from organosolv lignin and silver nanoparticles (AgNPs). Lignin was isolated from Parthenium hysterophorus using acidified methanol and used to synthesize lignin capped silver nanoparticles. Lignin–toluene diisocyanate film (Lg–TDI) was prepared by treating lignin (Lg) with toluene diisocyanate (TDI) followed by solvent casting to form films. Functional groups present and thermal properties of the films were evaluated using Fo…