Polyurethane
Mostrando 13-24 de 382 artigos, teses e dissertações.
-
13. Evaluation of a Graphite-Polyurethane Composite Electrode Modified with Copper Nanoparticles as an Amperometric Flow Detector in a Wall-Jet System for the Determination of Cysteine
A graphite-polyurethane composite electrode (GPUE) was modified by electrodeposition of copper nanoparticles (CuNP) followed by electrochemical treatment in NaOH (GPUE-CuNP), in order to prepare an amperometric sensor for the determination of cysteine (Cys). Cyclic votammograms of Cys solutions at GPUE-CuNP allowed the description of a sequence of electroche
J. Braz. Chem. Soc.. Publicado em: 2020-02
-
14. Polyurethane/poly (Ionic Liquids) Cellulosic Composites and their Evaluation for Separation of CO2 from Natural Gas
The development of both versatile and inexpensive sorbents for CO2/CH4 separation has become one of the greatest challenges to the environment and natural gas processing. This study reports the preparation and characterization of polyurethane (PU)/ cellulose based poly(ionic liquid)(CPIL) composites for CO2/CH4 separation. PU matrix was reinforced with CPIL
Mat. Res.. Publicado em: 20/01/2020
-
15. Number of laminae on the mechanical behavior of glued laminated timber (glulam) of Toona ciliata produced with vegetable polyurethane adhesive
RESUMO A madeira laminada colada (MLC) é um material compósito obtido a partir da colagem de lâminas de madeira dispostas com as fibras paralelas entre si. O objetivo deste trabalho foi avaliar a influência do número de lâminas no comportamento mecânico de MLC de Toona ciliata produzidas com adesivo poliuretano de base vegetal. As vigas de MLC foram p
Ciênc. agrotec.. Publicado em: 20/12/2019
-
16. Weathering Resistance of Waterborne Polyurethane Coatings Reinforced with Silica from Rice Husk Ash
Abstract: Waterborne polyurethanes (WPUs) are interesting materials for coatings when compared to solvent-based polyurethanes, once that reducing the concentration of volatile organic compounds that are harmful for human health and the environment. However, the WPU has low weathering resistance. In order to improve this behavior among others properties, ino
An. Acad. Bras. Ciênc.. Publicado em: 25/11/2019
-
17. Strength and Stiffness of Cross Laminated Timber (CLT) panels produced with Pinus and Eucalyptus: experimental and analytical comparisons
ABSTRACT The CLT is a building material that comes mainly used in Europe where it was developed. Lightweight, sturdy and eco-friendly, this material has become one of the most important constructive methods in the world. CLT are panels formed by layers of wood glued to each other orthogonally, always in odd numbers, symmetrical with respect to the central la
Matéria (Rio J.). Publicado em: 25/11/2019
-
18. Production of Carbon Foams from Rice Husk
The production of a material with rigid, multifunctional three-dimensional porous structure at a low cost is still challenging to date. In this work, a light and rigid carbon foam was prepared using rice husk as the basic element through a simple fermentation process followed by carbonization. For the fermentation process, the amount of biological yeast (7.5
Mat. Res.. Publicado em: 11/11/2019
-
19. Influence of water absorption on glass fibre reinforced IPN composite pipes
Abstract Glass fibre reinforced composite pipes were fabricated by using an IPN blend of 0%, 10%, 20%, 30%, 40%, 50% PU prepolymer (Polyurethane) with VER(Vinylester) resin. The prepared IPN (Interpenetrating polymer networks) composite pipes were subjected to boiling water immersion tests in order to study the effect of moisture absorption characteristics.
Polímeros. Publicado em: 04/11/2019
-
20. Feasibility of the new method for orchid in vitro rooting using liquid and chemical sterilized culture medium under different sucrose concentration
Resumo A propagação in vitro de orquídeas é a única técnica comercial em larga escala para obtenção de plântulas saudáveis e de alta qualidade com origem clonal. O uso de novas tecnologias em sistemas de cultura de tecidos vegetais pode levar a aumentos de eficiência e redução de custos dos sistemas de micropropagação. O principal sistema de m
Ornam. Hortic.. Publicado em: 28/10/2019
-
21. A New Electrochemical Platform Based on a Polyurethane Composite Electrode Modified with Magnetic Nanoparticles Coated with Molecularly Imprinted Polymer for the Determination of Estradiol Valerate in Different Matrices
A polyurethane composite electrode modified with magnetic nanoparticles (mag; Fe3O4) coated with molecularly imprinted polymers (MIPs) was developed for the electrochemical determination of estradiol valerate. Chemical and morphological analyses of the mag-MIP were performed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (E
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
-
22. Painéis de pínus e bagaço de cana empregando-se dois adesivos para uso na construção civil
Resumo O presente trabalho objetivou produzir e avaliar painéis aglomerados empregando-se partículas de bagaço de cana-de-açúcar (Saccharum officinarum) e de pínus (Pinus taeda, Pinus elliottii), comparando-se a eficiência de dois adesivos, ureia-formaldeído e poliuretano derivado do óleo de mamona. Os painéis foram preparados com 60% de partícula
Ambient. constr.. Publicado em: 03/10/2019
-
23. Lithium catalyst concentration influence on bio-polyols structure and polyurethane adhesives properties
ABSTRACT Polyol structure can be affected by the catalyst used for its synthesis and may affect the curing kinetics and mechanical strength of the final polyurethane (PU). This work aimed to study the influence of catalyst concentration on the structure of bio-based polyols and on the final properties of the polyurethane adhesive obtained from these polyols.
Matéria (Rio J.). Publicado em: 16/09/2019
-
24. The role of bondline thickness on mechanical properties of bio-based polyurethane
ABSTRACT Bio-based adhesives have been largely applied on several applications in many industrial areas, including automotive and laminated food packaging. Polyurethanes (PU) occupy a leading position among the most used bio-based polymers due to their large range of properties and application versatility. Recent works reported that PU obtained from castor o
Matéria (Rio J.). Publicado em: 16/09/2019