Advanced Magnetic Nanocomposites

This book is a collection of research articles and review articles, which was published in the Special Issue "Advanced Magnetic Nanocomposites: Structural, Physical Properties and Application". This book ‘‘Advanced Magnetic Nanocomposites: Structural, Physical Properties and Application’’ discussed recent development on advanced magnetic nanoparticles and nanocomposites with detailed explanation of structural and physical characteristics, and further possible potential application

Investigation of isocyanate-based dual-cure resins and their suitability for additive manufacturing

The development of materials for vat photopolymerization printing technologies has gained increasing attention within the last ten years. To date, the choice of materials for this printing technology is limited to photopolymers that tend to result in highly crosslinked, but usually brittle material properties. In this work, a dual-cure approach was developed, with the target to improve the overall material properties of 3D printed objects. For this purpose, the orthogonal and sequential polymerization of acrylate- and polyisocyanate based precursors was investigated. Photosensitive polyurethane acrylates were synthesized and mixed with low viscous polyisocyanates. The sequential polymerization was triggered by UV-light and heat, respectively. The reaction of the isocyanate groups in the heat, resulted in a polyurea network, confirmed by infrared spectroscopy. The morphology of resulting combined networks was systematically investigated by dynamic mechanical analysis and atomic force microscopy and showed that phase-separated morphologies with two distinct glass transition temperatures were formed, leading to a 10 fold increase in toughness in comparison to the neat polymeric networks. First printing trials showed the feasibility of the resin system for vat photopolymerization. The approach was extended to the sequential polymerization of isocyanate terminated prepolymers and low viscous acrylates. Varying the crosslinking densities of each polymeric network resulted in different morphologies as well as thermomechanical properties. Typical elastomers were obtained by a low crosslinking density of both polymeric networks. Cyclic loading-unloading measurements on 3D printed specimen showed the energy elastic behavior of the materials and an elongation at break of 101 % and a tensile strength of 3.4 N·mm-2 were achieved. A dual-cure resin based on acrylate-functionalized polyisocyanates was evaluated and resulted in thermally- and chemically stable 3D printed materials with the option to generate adoptable and catalytically active surfaces. The suitability of this resin to 3D print chemical reaction ware was demonstrated. In summary, the results obtained in this work show the tuneability and variability of combining acrylate- and polyisocyanate precursors, contributing to the increasing demand of new and improved materials for vat photopolymerization

Index to 1981 NASA Tech Briefs, volume 6, numbers 1-4

Short announcements of new technology derived from the R&D activities of NASA are presented. These briefs emphasize information considered likely to be transferrable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. This index for 1981 Tech Briefs contains abstracts and four indexes: subject, personal author, originating center, and Tech Brief Number. The following areas are covered: electronic components and circuits, electronic systems, physical sciences, materials, life sciences, mechanics, machinery, fabrication technology, and mathematics and information sciences

Magnetic Hybrid-Materials

Externally tunable properties allow for new applications of suspensions of micro- and nanoparticles in sensors and actuators in technical and medical applications. By means of easy to generate and control magnetic fields, fluids inside of matrices are studied. This monnograph delivers the latest insigths into multi-scale modelling, manufacturing and application of those magnetic hybrid materials

Polymer Composites for Electrical and Electronic Engineering Application

Polymer composite materials have attracted great interest for the development of electrical and electronic engineering and technology, and have been widely applied in electrical power systems, electrical insulation equipment, electrical and electronic devices, etc. Due to the significant expansion in the use of newly developed polymer composite materials, it is necessary to understand and accurately describe the relationship between composite structure and material properties, as only based on thorough laboratory characterization is it possible to estimate the properties for their future commercial applications. This book focuses on polymer composites applied in the field of electrical and electronic equipment, including but not limited to synthesis and preparation of new polymeric materials, structure–properties relationship of polymer composites, evaluation of materials application, simulation and modelling of material performance

Magnetic Hybrid-Materials

Externally tunable properties allow for new applications of suspensions of micro- and nanoparticles in sensors and actuators in technical and medical applications. By means of easy to generate and control magnetic fields, fluids inside of matrices are studied. This monnograph delivers the latest insigths into multi-scale modelling, manufacturing and application of those magnetic hybrid materials

Cumulative index to NASA Tech Briefs, 1970-1975

Tech briefs of technology derived from the research and development activities of the National Aeronautics and Space Administration are presented. Abstracts and indexes of subject, personal author, originating center, and tech brief number for the 1970-1975 tech briefs are presented

Nanoprobes for Tumor Theranostics

This book reports cutting-edge technology in nanoprobes or nanobiomaterials used for the accurate diagnosis and therapy of tumors, involving a multidisciplinary of chemistry, materials science, oncology, biology, and medicine

Significant NASA inventions available for licensing in foreign countries

Abstracts of various NASA-owned inventions which are available for foreign licensing in the identified countries are listed in accordance with the NASA Patent Licensing Regulations. Instructions for requested applicatons are explained