Three-dimensional radical polymerization

e-Polymers ◽  
2002 ◽  
Vol 2 (1) ◽  
Author(s):  
Gennadii V. Korolev ◽  
Maria L. Bubnova
Keyword(s):  
Radical Polymerization ◽  
New Technologies ◽  
Three Dimensional ◽  
Recent Decade ◽  
Kinetics And Mechanism ◽  
Principal Characteristics ◽  
Analytical Review ◽  
Engineering Information ◽  
Nmr Diffusion ◽  
Reaction Media

AbstractThis is an analytical review on kinetics and mechanism of threedimensional radical polymerization (TDRP) of multifunctional vinyl monomers (oligomers) having two or more double bonds per molecule. The period (1960 - 1977) of establishing the fundamental kinetic law of TDRP and the principal characteristics of its mechanism, i.e., microheterogeneity, is briefly described. New intense progress in the field of TDRP (during the recent decade) resulting from the development of new technologies based on this technique (fiber-optic engineering, information technology, etc.) has received much consideration. The methodological peculiarities of investigations on TDRP kinetics and mechanism, which are a result of the complex conditions of highly structured reaction media inherent in TDRP processes, are described. Particular attention is given to techniques of structuralphysical investigation (a consistent complex of methods including ESR, NMR, diffusion and radiation probing, mechanics and thermomechanics) sensitive to structural microheterogeneity in the range 10-6 - 10-4 cm. The perspectives of macromolecular design based on TDRP data are analyzed including latest approaches as the employment of a ‘living’ chain mode. This review covers three monographs in Russian, reflecting three sequential stages of TDRP development from 1960 till 1995 using acrylic oligomers as an example (most of the investigations were carried out at the Institute of Chemical Physics RAS). The bibliography includes 197 references.

scholarly journals 3D Printing of High Viscosity Reinforced Silicone Elastomers

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2239
Author(s):  
Nicholas Rodriguez ◽  
Samantha Ruelas ◽  
Jean-Baptiste Forien ◽  
Nikola Dudukovic ◽  
Josh DeOtte ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
New Technologies ◽  
Three Dimensional ◽  
High Viscosity ◽  
Layer By Layer ◽  
Silicone Elastomers ◽  
Uv Curable ◽  
Octet Truss ◽  
Tunable Mechanical Properties

Recent advances in additive manufacturing, specifically direct ink writing (DIW) and ink-jetting, have enabled the production of elastomeric silicone parts with deterministic control over the structure, shape, and mechanical properties. These new technologies offer rapid prototyping advantages and find applications in various fields, including biomedical devices, prosthetics, metamaterials, and soft robotics. Stereolithography (SLA) is a complementary approach with the ability to print with finer features and potentially higher throughput. However, all high-performance silicone elastomers are composites of polysiloxane networks reinforced with particulate filler, and consequently, silicone resins tend to have high viscosities (gel- or paste-like), which complicates or completely inhibits the layer-by-layer recoating process central to most SLA technologies. Herein, the design and build of a digital light projection SLA printer suitable for handling high-viscosity resins is demonstrated. Further, a series of UV-curable silicone resins with thiol-ene crosslinking and reinforced by a combination of fumed silica and MQ resins are also described. The resulting silicone elastomers are shown to have tunable mechanical properties, with 100–350% elongation and ultimate tensile strength from 1 to 2.5 MPa. Three-dimensional printed features of 0.4 mm were achieved, and complexity is demonstrated by octet-truss lattices that display negative stiffness.

scholarly journals A Review on Biosensors and Recent Development of Nanostructured Materials-Enabled Biosensors

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1109
Author(s):  
Varnakavi. Naresh ◽  
Nohyun Lee
Keyword(s):  
High Surface ◽  
Three Dimensional ◽  
Biological Response ◽  
Volume Ratio ◽  
Recent Decade ◽  
Disease Diagnosis ◽  
Electrical Signal ◽  
Detection Sensitivity ◽  
Wide Range ◽  
Color Tunability

A biosensor is an integrated receptor-transducer device, which can convert a biological response into an electrical signal. The design and development of biosensors have taken a center stage for researchers or scientists in the recent decade owing to the wide range of biosensor applications, such as health care and disease diagnosis, environmental monitoring, water and food quality monitoring, and drug delivery. The main challenges involved in the biosensor progress are (i) the efficient capturing of biorecognition signals and the transformation of these signals into electrochemical, electrical, optical, gravimetric, or acoustic signals (transduction process), (ii) enhancing transducer performance i.e., increasing sensitivity, shorter response time, reproducibility, and low detection limits even to detect individual molecules, and (iii) miniaturization of the biosensing devices using micro-and nano-fabrication technologies. Those challenges can be met through the integration of sensing technology with nanomaterials, which range from zero- to three-dimensional, possessing a high surface-to-volume ratio, good conductivities, shock-bearing abilities, and color tunability. Nanomaterials (NMs) employed in the fabrication and nanobiosensors include nanoparticles (NPs) (high stability and high carrier capacity), nanowires (NWs) and nanorods (NRs) (capable of high detection sensitivity), carbon nanotubes (CNTs) (large surface area, high electrical and thermal conductivity), and quantum dots (QDs) (color tunability). Furthermore, these nanomaterials can themselves act as transduction elements. This review summarizes the evolution of biosensors, the types of biosensors based on their receptors, transducers, and modern approaches employed in biosensors using nanomaterials such as NPs (e.g., noble metal NPs and metal oxide NPs), NWs, NRs, CNTs, QDs, and dendrimers and their recent advancement in biosensing technology with the expansion of nanotechnology.

Molding of Three-Dimensional Microcomponents

2006 ◽  
Author(s):  
W. N. P. Hung ◽  
M. M. Agnihotri ◽  
M. Y. Ali ◽  
S. Yuan
Keyword(s):  
Focused Ion Beam ◽  
New Technologies ◽  
Electrical Discharge Machining ◽  
Ion Beam ◽  
Semiconductor Industry ◽  
Three Dimensional ◽  
Cost Effective ◽  
Molecular Structures ◽  
Minimum Size ◽  
Ion Beam Sputtering

Traditional micromanufacturing has been developed for semiconductor industry. Selected micro electrical mechanical systems (MEMS) have been successfully developed and implemented in industry. Since current MEMS are designed for manufacture using microelectronics processes, they are limited to two-dimensional profiles and semiconductor based materials. Such shape and material constraints would exclude many applications that require biocompatibility, dynamic stress, and high ductility. New technologies are sought to fabricate three dimensional microcomponents using robust materials for demanding applications. To be cost effective, such microdevices must be economically mass producible. Molding is one of the promising replication techniques to mass produce components from polymers and polymer-based composites. This paper presents the development of a micromolding process to produce thermoplastic microcomponents. Mold design required precision fitting and was integrated with a vacuum pump to minimize air trap in mold cavities. Nickel and aluminum mold inserts were used for the study; their cavities were fabricated by combinations of available micromachining processes like laser micromachining, micromilling, micro electrical discharge machining, and focused ion beam sputtering. High and low density polyethylene, polystyrene polymers were used for this study. The effects of polymer molecular structures, molding temperature, time, and pressure on molding results were studied. Simulation of stress in the microcomponents, plastic flow in microchannels, and mold defects was performed and compare with experimental data. The research results showed that a microcomponent can be fabricated to the minimum size of 10 ± 1μm (0.0004 inch) with surface roughness <10 nm Rt. Molding of micro-size geartrains and orthopedic meso-size fasteners was completed to illustrate the capability of this process.

Innovations in Learning and Teaching for Manufacturing Engineering under Ubiquitous Computing and Distributed on Mobile Devices Smartphones and Tablets

2017 ◽  
Vol 903 ◽  
pp. 84-91
Author(s):  
Carlos Pazo Martín ◽  
Francisco Aguayo González ◽  
María Estela Peralta Álvarez ◽  
Mariano Marcos Bárcena ◽  
María Jesús Ávila Gutiérrez
Keyword(s):  
Mobile Devices ◽  
Teaching And Learning ◽  
Information Technologies ◽  
New Technologies ◽  
Educational Innovation ◽  
Information And Communications Technology ◽  
Learning And Teaching ◽  
Information And Communication ◽  
Engineering Information ◽  
Manufacturing Engineering

The new technologies of information and communication have opened up new possibilities for training in the field of manufacturing engineering. Information and communications technology contribute to flexible process of teaching and learning thanks to the ease of creating, processing and dissemination of content. They are also an opportunity to improve new learning environments, closer to actual production contexts. But to achieve an efficient process of learning, methodologies (that are based on ICT) should be adapted to the students’ characteristics, the contents and the context. This paper aims to design a model of teaching and learning from educational innovation with the use of information technologies applied to training Manufacturing Engineer using mobile devices as a teaching resource. The tool will be designed to self-education situated in learning contexts and incorporates different instructional strategies for student learning and teacher monitoring.

scholarly journals Three-dimensional Super-resolved Imaging of Paraffin-embedded Kidney Samples

2021 ◽  
Author(s):  
David Unnersjoe-Jess ◽  
Amer Ramdedovic ◽  
Martin Hoehne ◽  
Linus Butt ◽  
Felix C Koehler ◽  
...  
Keyword(s):  
New Technologies ◽  
Three Dimensional ◽  
Kidney Tissue ◽  
Confocal Imaging ◽  
Disease Assessment ◽  
Gold Standard Method ◽  
Filtration Barrier ◽  
Formalin Fixed Paraffin ◽  
Formalin Fixed Paraffin Embedded ◽  
Monitoring Treatment

Diseases of the glomeruli, the renal filtration units, are a leading cause of progressive kidney disease. Assessment of the ultrastructure of podocytes at the glomerular filtration barrier is essential for diagnosing diverse disease entities, providing insight into the disease pathogenesis as well as monitoring treatment responses. New technologies, including super-resolved nanoscopy and expansion microscopy, as well as new sample preparation techniques, are starting to revolutionize imaging of biopsy specimens. However, our previous approaches for simple and fast three-dimensional imaging of optically cleared samples are to date not compatible with formalin fixed paraffin-embedded (FFPE) tissue, impeding application in clinical routine. Here we provide protocols that circumvent these limitations and allow for three dimensional STED and confocal imaging of FFPE kidney tissue with similar staining and image quality as compared to our previous approaches. This would increase the feasibility to implement these protocols in clinical routines, as FFPE is the gold standard method for storage of patient samples.

scholarly journals Organic Nanoplatforms for Iodinated Contrast Media in CT Imaging

Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7063
Author(s):  
Peng Zhang ◽  
Xinyu Ma ◽  
Ruiwei Guo ◽  
Zhanpeng Ye ◽  
Han Fu ◽  
...  
Keyword(s):  
Contrast Media ◽  
New Technologies ◽  
Drug Loading ◽  
Three Dimensional ◽  
Disease Diagnosis ◽  
Ct Imaging ◽  
Water Soluble ◽  
Iodinated Contrast Media ◽  
Iodinated Contrast ◽  
Anatomical Images

X-ray computed tomography (CT) imaging can produce three-dimensional and high-resolution anatomical images without invasion, which is extremely useful for disease diagnosis in the clinic. However, its applications are still severely limited by the intrinsic drawbacks of contrast media (mainly iodinated water-soluble molecules), such as rapid clearance, serious toxicity, inefficient targetability and poor sensitivity. Due to their high biocompatibility, flexibility in preparation and modification and simplicity for drug loading, organic nanoparticles (NPs), including liposomes, nanoemulsions, micelles, polymersomes, dendrimers, polymer conjugates and polymeric particles, have demonstrated tremendous potential for use in the efficient delivery of iodinated contrast media (ICMs). Herein, we comprehensively summarized the strategies and applications of organic NPs, especially polymer-based NPs, for the delivery of ICMs in CT imaging. We mainly focused on the use of polymeric nanoplatforms to prolong circulation time, reduce toxicity and enhance the targetability of ICMs. The emergence of some new technologies, such as theragnostic NPs and multimodal imaging and their clinical translations, are also discussed.

scholarly journals Virtual and Space Tourism as New Trends in Travelling at the Time of the COVID-19 Pandemic

2022 ◽  
Vol 14 (2) ◽  
pp. 628
Author(s):  
Michał Roman ◽  
Robert Kosiński ◽  
Kumar Bhatta ◽  
Arkadiusz Niedziółka ◽  
Andrzej Krasnodębski
Keyword(s):  
Public Space ◽  
New Technologies ◽  
Space Station ◽  
Three Dimensional ◽  
Developed Countries ◽  
Google Earth ◽  
Alternative Form ◽  
Original Form ◽  
Space Tourism ◽  
The World

The first European COVID-19 infection was recorded in February 2020, and Poland followed in mid-March. Restrictions were imposed on traveling between states and using public space. These movement restrictions forced a search for new, often innovative, forms of tourism. Google Earth virtual reality (VR), Google Street View, and the Chernobyl VR Project are just some of the selected opportunities to create virtual tours. Different activities using VR mean that people can experience the illusion of travelling in time and space, outside of their everyday surroundings, in a digitally constructed three-dimensional (3D) environment, for cognition or entertainment. Therefore, this study aimed to present virtual and space tourism as new traveling trends during various crise,s such as health, economic, etc. A diagnostic survey with a developed questionnaire was conducted in June and July 2021 in Poland. A total of 564 fully answered responses were collected from randomly selected respondents. We found that around 82% of Polish people were aware of VR technology, and 70% believed that new technologies determine VR tourism development. VR presents the possibility of travelling to places that no longer exist in their original form, but have been reconstructed only in VR. Around 75% of the respondents agreed that VR tourism plays an essential role in tourism promotion in Poland and throughout the world. Moreover, VR and augmented tourism lets us visit fictitious and dangerous, politically restricted, and geographically as well as economically difficult destinations. For example, our results revealed that many people want to experience North Korea, the USA, Antarctica, Syria, etc. At the same time, people recommended the NASA space station as a visiting destination using VR and augmented reality. VR offers an alternative form of tourism during crises and pandemics such as COVID-19. We found over 26% of the respondents were satisfied with contemporary tourists’ cognitional needs during VR sightseeing. More than 87% of the respondents believed that VR tourism cannot substitute real-world tourism in the long run. However, VR tourism will be more beneficial for developing countries facing difficulties in economic aspects, and easier than attaining visas to enter developed countries. Furthermore, virtual sightseeing may also constitute an alternative for people who are disabled or sick, and who cannot undertake the effort of active tourism and explore tourist resources of the world on their own.

scholarly journals A Review on the Fabrication and Reliability of Three-Dimensional Integration Technologies for Microelectronic Packaging: Through-Si-Via and Solder Bumping Process

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1664
Author(s):  
Do Hoon Cho ◽  
Seong Min Seo ◽  
Jang Baeg Kim ◽  
Sri Harini Rajendran ◽  
Jae Pil Jung
Keyword(s):  
High Speed ◽  
High Performance ◽  
New Technologies ◽  
Three Dimensional ◽  
High Density ◽  
Internal Stresses ◽  
Deep Reactive Ion Etching ◽  
Fifth Generation ◽  
Precise Understanding ◽  
Fabrication Defects

With the continuous miniaturization of electronic devices and the upcoming new technologies such as Artificial Intelligence (AI), Internet of Things (IoT), fifth-generation cellular networks (5G), etc., the electronics industry is achieving high-speed, high-performance, and high-density electronic packaging. Three-dimensional (3D) Si-chip stacking using through-Si-via (TSV) and solder bumping processes are the key interconnection technologies that satisfy the former requirements and receive the most attention from the electronic industries. This review mainly includes two directions to get a precise understanding, such as the TSV filling and solder bumping, and explores their reliability aspects. TSV filling addresses the DRIE (deep reactive ion etching) process, including the coating of functional layers on the TSV wall such as an insulating layer, adhesion layer, and seed layer, and TSV filling with molten solder. Solder bumping processes such as electroplating, solder ball bumping, paste printing, and solder injection on a Cu pillar are discussed. In the reliability part for TSV and solder bumping, the fabrication defects, internal stresses, intermetallic compounds, and shear strength are reviewed. These studies aimed to achieve a robust 3D integration technology effectively for future high-density electronics packaging.

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