Essays on Polymers

Overview

Polyvinylidene fluoride is one of the polymers that are used as membrane material. This is because of its outstanding properties. Besides its comparatively high amount of fluorine, the polymer also has a high level of crystallinity. The result of these properties are exhibited in the performance of the Polyvinylidene fluoride polymer. For instance, the chemical stability of Polyvinylidene fluoride in chlorinated solvents and environments that are highly caustic and acidic is very high. Another property of the polymer is its hydrophobicity. This means that it is not compatible with water. This would create challenges if the polymer were to ...

Introduction

Waste is generated as a result of a lot of physical, chemical, and biological processes. Dumping it at some appropriate place is one option. However, ecological effects of throwing away waste products are becoming a serious concern these days. In order to minimize waste, the best strategy is to transform it into valuable products . Plenty of research studies have been carried out to utilize waste effectively. The aim of this report is analysis of the proposed methods for the utilization of common forms of wastes for useful purposes. We also recommend better alternatives to help create a lesser negative ...

Biomolecules serve different functions in a cell. The three major classes of biomolecules in the cell are: proteins, nuclei acids and carbohydrates. These molecular structures serve nearly similar functions in most organisms. Though the function of protein in forming cell architecture, signaling and communication is well known, little is known about the role of carbohydrate in communication. Nevertheless, it goes un-denying that carbohydrates are indispensable for cellular communication and signaling, just like proteins and nucleic acids. The paper titled, Carbohydrates in Cell Recognition, by the authors Nathan Sharon and Halina Lis, is a good review that elucidates the significance ...

Introduction

There are different perspectives that are being peddled concerning fracture processes, this has led to confusion on what actually this term means. In this review, a deeper understanding is sort by analyzing different aspects of the nomenclature of the fracture process. In order to gain a deeper understanding of the failure processes several aspects are put in consideration key among them will be discussed below and include; the energy of fracture, macroscopic structure path and microscopic fracture mechanisms.

Energy to Break

The toughness of a material is the measure of the absorbed energy during and before fracture. The toughness of the material ...

Definition of Coatings

Coating is the process whereby one material is used to continuously cover another surface. According to Dewo et al. (2015), coating is a surface modification approach that involves the addition of a new material onto the surface of a substance or element that is at risk of corrosion.

Formula: Rusting of Iron.

iron + oxygen + water ==> hydrated iron(III) oxide (RUST) 4Fe(s) + 3O2(g) + xH2O(l) ==> 2Fe2O3.xH2O(s)

Different Types of Coatings

The process of coating utilizes multiple films of coatings as primers and top layers. The purpose of each layer is particular; however, the layers often interact with one another (Özçam et ...

Lignin Chemistry

Lignin History Lignin is a plant-derived biopolymer with several applications. It is considered an effective alternative to chemically synthesized plastics that pose serious environmental problems during manufacture and disposal. Lignin is often obtained as a byproduct in paper and pulp manufacture. Lignin has to be dissolved to obtain cellulose from wood. In 1838, Anselme Payen discovered that wood contained cellulose, and oxidizable coatings (later called lignin) that bind the cellulose together (McCarthy and Islam, 2000). This coating material could be removed from wood after acid treatment and washing with an aqueous alkali solution (McCarthy and Islam, 2000). Later, several ...

The term organic semiconductor is used for denoting the class of materials that are based on carbon, which takes part in semiconducting characteristics. And therefore, many of the attractive optoelectronic features exhibited in organic semiconductors emerge from the properties of carbon atoms. Organic semiconductor materials fall into two broad categories, i.e., low-molecular weight organic materials and polymers (Ishii et al. 2009). The individual energy properties are different as can be seen below. The bonding nature manifested in organic semiconductors is fundamentally dissimilar from those seen in their inorganic counterparts. The solid molecular crystals of organic semiconductors are bonded with ...

Polymers cells are the next-generation class of photovoltaic since they promise realization of light weights, mechanically flexible, larger area devices. The room temperature solution processing can be used in fabricating these devices. High-efficiency conversion power of about 10% has recently been obtained in tandem polymer cells (Huo et al., 2015). In single-junction, it’s achievable through lowering the density state to a level lower than the electron acceptor and the conduction band of the semi-conductor. Photovoltage is electromotive force obtained by a photosensitive material due to inducing radiant energy; photovoltaic relates electric current produced at a junction of two ...

Assumptions in Molecular Weight Determination and their impact on MW determination

DSC measures the quantity of required heat necessary to melt a sample where the heat of fusion is calculated based on a percentage of crystallinity. Therefore, the methods used to measure crystallinity, weight determination such as DSC must be detailed to retrieve valuable results. However, in most of the molecular weight determination methods, there are certain assumptions undertaken but those assumptions also have a certain impact on results. In DSC profile, three types of distinct probabilities of uncertainty exist. The first is natural uncertainty that may be linked to equipment such as uncertainty of weight measurements of the sample. ...

0. Introduction Moto-cars are made from metals. This very common opinion was almost entirely true during almost all the previous century though opposite solitary examples (displayed at images below) are very well known for car likers: wooden bulks, a rubber car, a fiberglass sport car, a car with plastic bulk facias based on soybeans, a concept of a ceramic car, a glass car, and so on. All those examples are just very rare exceptions. Moreover, the probably refer rather to arts than to industry. However, in the current century, metals lost their monopoly. In the present essay, several material ...

Polyisocyanurate or Polyiso or ISO owes its popularity to its excellent thermal insulation performance (determined by its R-value). This thermosetting polymer gets its hardened, irreversible, and thermally insulating molecular structure with the application of heat. This property of Polyisocyanurates is particularly useful for roofing insulation applications. But the advantages of these materials and their significance do not end with just one property. There is a significant amount of reasons why many constructors prefer to use these polymers over others as a viable insulation material for their roofing materials. This essay is an attempt to study the significance of Polyisocyanurate ...

Wallace Carothers

life and Education of Wallace Carothers Wallace Hume Carothers was born on April 27, 1896. He was born in Burlington, Iowa. He was the son of Ira and Mary Carothers, and was the oldest children in the family. When he was five years old, his family moved to Des Moines, Iowa. There he studied in high school. He started showing interest in science during high school years and started reading the scientific literature. During his studies, he liked to play with different tools, instruments, and other mechanical items, and liked to spend time in experimenting. He used to have ...

Melt spinning refers to a method that is used to cool liquids in a rapid manner. The method involves the internal cooling of a wheel using liquid nitrogen or water. The wheel is then rotated as it cools. A liquid is streamed onto the cooling wheel, and that causes it to solidify rapidly. Melt Spinning is used in the development of objects that demand high cooling rates for them to form. A good example of such material is metallic glass. Polymers that can undergo melting use the melt spinning technique (NPTEL, 2010). Examples of such polymers include polyester; sulfur; ...

Abstract

Maintaining a highly effective waste management system is an important part of being a clean and green city. While this may not be the top priority for some countries, especially the developing ones—because keeping a clean and green city can be costly; there are countries that are making long term investments for a more effective waste management system in the future. This can be evidenced by the fact that even countries like Qatar and the city of Dubai are finding it hard to find the political and economic will to develop and enforce environmental law and regulations. If ...

Chemistry

2. The nano carrier needs to remain in suspension in H2O, PBS, human serum, etc. What type of polymer do you need to use to decorate the surface of the nanocarrier to achieve this goal? In order to maintain the nanocarrier in suspension in water, Phosphate-Buffered Saline (PBS), human serum a suitable solution a polymer is needed on its surface. The polymer used needs to accomplish three goals. The polymer needs to decorate the nanocarrier surface to enhance suspension and secondly, to prevent protein absorption. Another characteristic is that the polymer evades the immune system. PLGA poly(lactic-co-)glycolic ...

Scientific Report

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Abstract

The experiment was performed to analyze the outcomes of temperature on the ability of fungal and bacterial amylase to breakdown starch to maltose. Therefore, the study will reveal the optimal temperature for amylase activity. The initial steps include preparing the materials and tools used during the experiment. A timetable for comparing temperature and function was generated. Test tubes and plates were properly labeled. Iodine was needed for every spot plate so that the fungal amylase, bacterial amylase, fungal amylase and the starch solution can be added to the iodine in a time and temperature dependent fashion. Observing ...