Polymer conformations

A well discussed subject in polymer science and technology is the field of chain conformations. For decades now, scientists have been suggesting conformation and configuration models that explain partially or completely the behavior of single and grouped polymeric chains. Both topics can be discussed on a statistical, thermodynamic, or mechanical basis since both conformations and configuration are affected by such factors.

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Polymers classification

The basic classification of polymers is based on their origin, and two major categories are identified: natural and synthetic ones. Natural polymers are found in nature and their structures are commonly more complicated than synthetics’ structures. Their greatest advantages include their biodegradability and their abundance. Synthetic polymers on the other hand are man made from crude oil and similar sources. Most synthetic polymers are not biodegradable although progress has been made towards manufacturing of biodegradable or partially degradable synthetic polymers in the last decade. Synthetic polymers can be tailored to reach any set of mechanical, thermal, chemical and physical properties via synthetic approaches and their raw material is quite cheap.

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Chain Polymerization types

Free radical polymerization has been studied and used extensively for decades. Free radicals are the key components in this polymerization type. Free radical sare highly unstable structures with just one free electron that usually comes from a homolytic breaking of a covalent bond. Usually, a covalent bond is broken in the presence of an initiator that provides the necessary energy or activation energy reduction to induce the homolytic bond breaking. When one electron is found in a free radical, it causes very high reactivity towards third bodies and especially towards structures with shared electrons such as double bonds.

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Biocompatible coatings and coatings of medical devices

Medical devices require coatings that either are inert and they do not pose a threat to human health or coatings that are designed for controlled release of bio compounds into blood, skin or tissues. Such coatings have been based on natural and synthetic polymers and have been formulated either as homopolymers or copolymers. Some of the most popular choices that exhibit properties desired in this project include:

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CMAS molten deposits on Thermal Barrier Coatings: Novel solutions

Perhaps the greatest issue nowadays for Thermal Barrier Coatings self life and efficiency comes from the deposit of molten Calcium Magnesium Alumino Silicates (also termed as CMAS). These deposits come mainly from atmospheric debris and they melt on the thermal barrier coating surfaces or during their travel towards the TBC surface. These deposits can cause the dissolution of thermal barrier coatings into them, opening cracks down to the metal surface and causing complete destruction of both TBC’s and composite’s integrity. The problem is of even higher significance in the case of high temperature gas turbines (1400-1500K currently) where the molten deposits lead to deactivation of thermal barrier coating protection.

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Introduction to Thermal Barrier Coatings

Thermal barrier coatings (TBCs) are used to protect mechanical parts and metal surfaces from mechanical, chemical and physical degradation. They are mainly employed in cases were very high temperatures exist such as diesel engines, turbines and other related applications. Their aim is to provide adequate resistance to the metal surface beneath which is exposed to high temperatures, a variety of chemical species for different time ranges. In order to do so, thermal barrier coatings require specific properties including very low thermal conductivity, absence of phase transformations within the temperature range of application, excellent adherence to the metal surface beneath, specific porosity, comparable thermal expansion coefficient to that of the substrate and very high melting. Chemical inertness is typically another requirement that has been reevaluated over the last years.

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Current gaps in computational chemistry and CFD software packages

Computational chemistry approaches offer capabilities for the prediction of chemical, physical, mechanical and electronic properties that could only be imagined ten years ago. Various methods and approaches allows scientists to predict behavior of chemical, physical and electronic systems with experimental accuracy, taking advantages of advances in the field of theoretical chemistry, computational hardware and cloud technology. Most computational chemistry packages offer parallel processing that allows the simultaneous solving of numerous differential equations and the application of endless trial and error loops. Novel solving algorithms have been integrated into these packages resulting to optimized solving processes with minimum required computational time and extreme prediction accuracy. However, gaps and significant margin for improvement still exist.

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Chemical detectors and sensors design via molecular simulation

Detection or sensing of various compounds is a key technology for the industrial, manufacturing, business and virtually any sector one can imagine. In order to improve safety and efficiency of processes whether these are the manufacturing of plastic cups or the indoors living of a family, one has to be able to monitor harmful agents at very low concentrations with accuracy, repeatability and affordable cost.

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Computational Chemistry in Education sector

Computational Chemistry [Theoretical Chemistry] can be a powerful tool in educational sector, for both beginners and experts in the fields of Chemistry, Chemical Engineering, Physics, Material Science and others. Some of the first barriers in the learning process of chemistry are how to perceive the chemical structures, the different approaches to model these chemical structures, and the mechanisms that chemical compounds use to react with each other. Computational Chemistry tools make this learning process easy, well understood and fun.

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