scholarly journals Internal donors on supported Ziegler Natta catalysts for isotactic polypropylene: a brief tutorial review

2021 ◽  
Vol 28 (10) ◽  
Author(s):  
Bharat R. Paghadar ◽  
J. B. Sainani ◽  
Samith K. M. ◽  
Poornima Bhagavath
Keyword(s):  
Polymeric Materials ◽  
Detailed Comparison ◽  
Short Review ◽  
Point Of View ◽  
Polymer Science ◽  
Cross Combination ◽  
Polymer Properties ◽  
Technical Advances ◽  
Catalyst Systems ◽  
New Applications

AbstractThe scientific and technical advances in the field of polymer science has been abundant in recent years. Amongst the various polymeric materials available in market, synthesis of polyolefins has been in the forefront since decades. A major challenge in this domain remains in attaining stereoregular polyolefins especially polypropylene (PP) and significant efforts were carried out by synthesizing various internal donors (ID) aiding the catalysts involved in producing them. This short review gives an overview of i) various generations of Ziegler–Natta (ZN) catalyst systems ii) general classes of ID that has been demonstrated by the researchers over the past decades iii) their influence on PP isotacticity and polymer properties. The coordination modes of different donor classes on supported ZN system and comparative study especially between phthalate and diether ID classes were also addressed here. This review also presents the studies carried out on phthalate catalyst structure analysis, detailed comparison study on phthalate and diether IDs in terms of PP isotacticity, regioselectivity, hydrogen response, and also their cross combination study and competitive behavior. Further a brief description on other structurally varied IDs like malonates, maleates, silyl diol esters, bifunctional donors, multi ether donors demonstrated for isotactic PP were also presented. Studies conducted on compatibility of incorporation of two different classes of IDs on a single supported ZN system for the fundamental understanding of the catalyst behavior; and also on how mixed donor approach enables in tuning the catalyst for polymer properties were also presented. This review also provides an opportunity to the young minds and the basic researchers from academic point of view by and large to create new polymeric materials with useful properties or modify the existing materials for new applications by incorporating new IDs for further improvisation of the stereo regularity in obtaining the polymers. Graphic Abstract

scholarly journals Recent Advances in Functional Polymer Materials for Energy, Water, and Biomedical Applications: A Review

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4327
Author(s):  
Yassine EL-Ghoul ◽  
Fahad M. Alminderej ◽  
Fehaid M. Alsubaie ◽  
Radwan Alrasheed ◽  
Norah H. Almousa
Keyword(s):  
Oil Recovery ◽  
Biomedical Applications ◽  
Academic Research ◽  
Polymeric Materials ◽  
Polymer Materials ◽  
Polymer Science ◽  
Energy Applications ◽  
Recent Advances ◽  
Treatment Technologies ◽  
New Applications

Academic research regarding polymeric materials has been of great interest. Likewise, polymer industries are considered as the most familiar petrochemical industries. Despite the valuable and continuous advancements in various polymeric material technologies over the last century, many varieties and advances related to the field of polymer science and engineering still promise a great potential for exciting new applications. Research, development, and industrial support have been the key factors behind the great progress in the field of polymer applications. This work provides insight into the recent energy applications of polymers, including energy storage and production. The study of polymeric materials in the field of enhanced oil recovery and water treatment technologies will be presented and evaluated. In addition, in this review, we wish to emphasize the great importance of various functional polymers as effective adsorbents of organic pollutants from industrial wastewater. Furthermore, recent advances in biomedical applications are reviewed and discussed.

scholarly journals Smartphone-Enabled Personalized Diagnostics: Current Status and Future Prospects

Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1067
Author(s):  
Karla Jaimes Merazzo ◽  
Joseba Totoricaguena-Gorriño ◽  
Eduardo Fernández-Martín ◽  
F. Javier del Campo ◽  
Eva Baldrich
Keyword(s):  
Mobile Devices ◽  
Point Of Care ◽  
Near Field ◽  
Short Review ◽  
Magnetic Sensors ◽  
Current Status ◽  
Wireless Power ◽  
Communication Devices ◽  
New Applications ◽  
The Internet Of Things

Smartphones are becoming increasingly versatile thanks to the wide variety of sensor and actuator systems packed in them. Mobile devices today go well beyond their original purpose as communication devices, and this enables important new applications, ranging from augmented reality to the Internet of Things. Personalized diagnostics is one of the areas where mobile devices can have the greatest impact. Hitherto, the camera and communication abilities of these devices have been barely exploited for point of care (POC) purposes. This short review covers the recent evolution of mobile devices in the area of POC diagnostics and puts forward some ideas that may facilitate the development of more advanced applications and devices in the area of personalized diagnostics. With this purpose, the potential exploitation of wireless power and actuation of sensors and biosensors using near field communication (NFC), the use of the screen as a light source for actuation and spectroscopic analysis, using the haptic module to enhance mass transport in micro volumes, and the use of magnetic sensors are discussed.

Carbon Dioxide as a Carbon Resource – Recent Trends and Perspectives

2012 ◽  
Vol 67 (10) ◽  
pp. 961-975 ◽  
Author(s):  
Markus Hölscher ◽  
Christoph Gürtler ◽  
Wilhelm Keim ◽  
Thomas E. Müller ◽  
Martina Peters ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Raw Materials ◽  
Low Cost ◽  
Polymeric Materials ◽  
Short Review ◽  
Chemical Research ◽  
Bond Forming ◽  
Bulk Chemicals ◽  
High Thermodynamic Stability ◽  
Recent Trends

With the growing perception of industrialized societies that fossil raw materials are limited resources, academic chemical research and chemical industry have started to introduce novel catalytic technologies which aim at the development of economically competitive processes relying much more strongly on the use of alternative carbon feedstocks. Great interest is given world-wide to carbon dioxide (CO2) as it is part of the global carbon cycle, nontoxic, easily available in sufficient quantities anywhere in the industrialized world, and can be managed technically with ease, and at low cost. In principle carbon dioxide can be used to generate a large variety of synthetic products ranging from bulk chemicals like methanol and formic acid, through polymeric materials, to fine chemicals like aromatic acids useful in the pharmaceutical industry. Owing to the high thermodynamic stability of CO2, the energy constraints of chemical reactions have to be carefully analyzed to select promising processes. Furthermore, the high kinetic barriers for incorporation of CO2 into C-H or C-C bond forming reactions require that any novel transformation of CO2 must inevitably be associated with a novel catalytic technology. This short review comprises a selection of the most recent academic and industrial research developments mainly with regard to innovations in CO2 chemistry in the field of homogeneous catalysis and processes.

The emergence of oxime click chemistry and its utility in polymer science

2016 ◽  
Vol 7 (23) ◽  
pp. 3812-3826 ◽  
Author(s):  
Joe Collins ◽  
Zeyun Xiao ◽  
Markus Müllner ◽  
Luke A. Connal
Keyword(s):  
Click Chemistry ◽  
Polymeric Materials ◽  
Polymer Science

The synthesis of new, highly functional and dynamic polymeric materials has risen dramatically since the introduction of click chemistry in 2001.

scholarly journals Peran Aplikasi “Visiting Jogja” dalam Mengembalikan Kepercayaan Wisatawan untuk Berwisata ke Yogyakarta

2021 ◽  
Vol 5 (2) ◽  
pp. 128
Author(s):  
Fitria Jalaluddin ◽  
Alfelia Nugky Permatasari
Keyword(s):  
Point Of View ◽  
The Public ◽  
Advantages And Disadvantages ◽  
Daily Mobility ◽  
Tourism Sector ◽  
Major Loss ◽  
Tourism Destinations ◽  
Tourism Attractions ◽  
New Applications ◽  
Special Region

Covid-19 made several countries adopt lock-down policies as an effort to break the chain of spreading the virus. However, this policy greatly affects sectors related to the daily mobility of people, especially the tourism sector which has been most significantly affected by Covid-19. One of the provinces in Indonesia that has experienced a major loss in the tourism sector due to Covid-19 is the Yogyakarta Special Region (DIY). Therefore, the DIY government gradually continues to encourage the tourism sector to resume operations, one of which is by releasing new applications for tourists, namely "Jogja Pass" and "Visiting Jogja" to monitor visitors to tourism destinations in DIY. In this study the author will focus on studying the application "Visiting Jogja". The purpose of this research is to examine the advantages and disadvantages of the "Visiting Jogja" application from the user's point of view, and to find out whether the "Visiting Jogja" application can help restore the confidence of tourists to travel to Yogyakarta. This study uses qualitative research methods, with data collection techniques through direct interviews with 10 respondents as a sample who is determined randomly. The results show that the application "Visiting Jogja" can provide assurance for tourists, which helps generate confidence in users to visit more tourism attractions in Yogyakarta. However, the government's efforts in socializing and promoting the “Visiting Jogja” application to the public are still lacking.

scholarly journals 3D Printing of Solvent-Free Supramolecular Polymers

2021 ◽  
Vol 9 ◽  
Author(s):  
Harald Rupp ◽  
Wolfgang H. Binder
Keyword(s):  
3D Printing ◽  
Dynamic Properties ◽  
Polymeric Materials ◽  
Fundamental Principle ◽  
Supramolecular Polymers ◽  
Fused Deposition Modelling ◽  
Self Healing ◽  
Polymer Science ◽  
Fused Deposition ◽  
Molecular Ordering

Additive manufacturing has significantly changed polymer science and technology by engineering complex material shapes and compositions. With the advent of dynamic properties in polymeric materials as a fundamental principle to achieve, e.g., self-healing properties, the use of supramolecular chemistry as a tool for molecular ordering has become important. By adjusting molecular nanoscopic (supramolecular) bonds in polymers, rheological properties, immanent for 3D printing, can be adjusted, resulting in shape persistence and improved printing. We here review recent progress in the 3D printing of supramolecular polymers, with a focus on fused deposition modelling (FDM) to overcome some of its limitations still being present up to date and open perspectives for their application.

Analysis of Omega-Gate Nanowire SOI MOSFET Under Analog Point of View

2020 ◽  
Vol 15 (1) ◽  
pp. 1-6
Author(s):  
Welder Fernandes Perina ◽  
João Antonio Martino ◽  
Paula Ghedini Der Agopian
Keyword(s):  
Point Of View ◽  
Short Channel Effects ◽  
Theoretical Limit ◽  
Short Channel ◽  
Worst Case ◽  
Channel Effects ◽  
Electrostatic Coupling ◽  
Channel Lengths ◽  
P Type ◽  
New Applications

This paper presents an evaluation of omega-gate nanowire n- and p-type SOI MOSFETs performance focusing on the main analog figures of merit. The different channel widths (WNW) and channel lengths (L) were also evaluated. These devices presented values of subthreshold slope near the theoretical limit at room temperature (60 mV/dec) and in the worst case a DIBL value smaller than 70 mV/V showing its immunity to short channel effects (SCEs) in the range studied. The narrowest device showed great electrostatic coupling, improving transconductance (gm), presenting an unit gain frequency over 200 GHz and intrinsic voltage gain over 80 dB. These values suggests that this device is capable of achieving good performance on new applications such as 5G communications and Internet-of-Things (IoT).

Polymer characterization

2004 ◽  
Author(s):  
Ian L. Hosier ◽  
Alun S. Vaughan
Keyword(s):  
Molecular Weight ◽  
Electrode Materials ◽  
Polymeric Materials ◽  
Optical Nonlinearity ◽  
Polymer Science ◽  
New Materials ◽  
Wide Range ◽  
Step Growth ◽  
Step Growth Polymerization ◽  
Increasing Demand

Polymer science is, of course, driven by the desire to produce new materials for new applications. The success of materials such as polyethylene, polypropylene, and polystyrene is such that these materials are manufactured on a huge scale and are indeed ubiquitous. There is still a massive drive to understand these materials and improve their properties in order to meet material requirements; however, increasingly polymers are being applied to a wide range of problems, and certainly in terms of developing new materials there is much more emphasis on control. Such control can be control of molecular weight, for example, the production of polymers with a highly narrow molecular weight distribution by anionic polymerization. The control of polymer architecture extends from block copolymers to other novel architectures such as ladder polymers and dendrimers. Cyclic systems can also be prepared, usually these are lower molecular weight systems, although these also might be expected to be the natural consequence of step-growth polymerization at high conversion. Polymers are used in a wide range of applications, as coatings, as adhesives, as engineering and structural materials, for packaging, and for clothing to name a few. A key feature of the success and versatility of these materials is that it is possible to build in properties by careful design of the (largely) organic molecules from which the chains are built up. For example, rigid aromatic molecules can be used to make high-strength fibres, the most highprofile example of this being Kevlar®; rigid molecules of this type are often made by simple step-growth polymerization and offer particular synthetic challenges as outlined in Chapter 4. There is now an increasing demand for highly specialized materials for use in for example optical and electronic applications and polymers have been singled out as having particular potential in this regard. For example, there is considerable interest in the development of polymers with targeted optical properties such as second-order optical nonlinearity, and in conducting polymers as electrode materials, as a route towards supercapacitors and as electroluminescent materials. Polymeric materials can also be used as an electrolyte in the design of compact batteries.

scholarly journals Recent Applications of Advanced Atomic Force Microscopy in Polymer Science: A Review

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1142 ◽  
Author(s):  
Phuong Nguyen-Tri ◽  
Payman Ghassemi ◽  
Pascal Carriere ◽  
Sonil Nanda ◽  
Aymen Amine Assadi ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Chemical Characterization ◽  
Super Resolution ◽  
Polymeric Materials ◽  
Polymer Materials ◽  
Polymer Science ◽  
Force Microscopy ◽  
Atomic Force ◽  
Nanoscale Characterization

Atomic force microscopy (AFM) has been extensively used for the nanoscale characterization of polymeric materials. The coupling of AFM with infrared spectroscope (AFM-IR) provides another advantage to the chemical analyses and thus helps to shed light upon the study of polymers. This paper reviews some recent progress in the application of AFM and AFM-IR in polymer science. We describe the principle of AFM-IR and the recent improvements to enhance its resolution. We also discuss the latest progress in the use of AFM-IR as a super-resolution correlated scanned-probe infrared spectroscopy for the chemical characterization of polymer materials dealing with polymer composites, polymer blends, multilayers, and biopolymers. To highlight the advantages of AFM-IR, we report several results in studying the crystallization of both miscible and immiscible blends as well as polymer aging. Finally, we demonstrate how this novel technique can be used to determine phase separation, spherulitic structure, and crystallization mechanisms at nanoscales, which has never been achieved before. The review also discusses future trends in the use of AFM-IR in polymer materials, especially in polymer thin film investigation.

scholarly journals Evaluation of Polymeric Materials for Chemical Enhanced Oil Recovery

Processes ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 361 ◽  
Author(s):  
Alison J. Scott ◽  
Laura Romero-Zerón ◽  
Alexander Penlidis
Keyword(s):  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Polymeric Materials ◽  
Polymer Flooding ◽  
Chemical Degradation ◽  
Polymer Composition ◽  
General Terms ◽  
Polymer Properties ◽  
Application Specific ◽  
Evaluation Techniques

Polymer flooding is a promising enhanced oil recovery (EOR) technique; sweeping a reservoir with a dilute polymer solution can significantly improve the overall oil recovery. In this overview, polymeric materials for enhanced oil recovery are described in general terms, with specific emphasis on desirable characteristics for the application. Application-specific properties should be considered when selecting or developing polymers for enhanced oil recovery and should be carefully evaluated. Characterization techniques should be informed by current best practices; several are described herein. Evaluation of fundamental polymer properties (including polymer composition, microstructure, and molecular weight averages); resistance to shear/thermal/chemical degradation; and salinity/hardness compatibility are discussed. Finally, evaluation techniques to establish the polymer flooding performance of candidate EOR materials are described.

Sign in / Sign up

Export Citation Format

Share Document