Polymer, any of a class of natural or synthetic substances composed of very large molecules, called macromolecules, that are multiples of simpler chemical units called monomers. Smart polymers and their applications sciencedirect. The polymer coating method does not require a drying step, as does the latex coating method. Low density polyethylene ldpe polymers are among the most common types of synthetic organic polymers, which are often found in households.
Biopolymers can be complex and nice introduction to materials science, chapter 15, polymer structures university tennessee, dept. Polymers that exhibit extreme elastic extensibility when subjected to relatively low mechanical stress also known as rubber some elastomers can be stretched by a factor of 10 and yet completely recover to their original shape although their properties are quite different from thermosets, they share a similar molecular structure. Shape memory polymers, smart polymer hydrogels, and selfhealing polymer systems are also explored. A variety of synthetic polymers as plastic polythene, synthetic fibres nylon 6,6 and synthetic rubbers buna s are examples of manmade polymers extensively used in daily life as well as in industry. When heated due to the absence of cross links, they become free to move and and can be moulded into any desired shapes. They are very flexible and have excellent resistance to heat, chemicals, and flame. There are three types of classification under this category, namely, natural, synthetic, and semisynthetic. Examples are proteins, cellulose, starch, resins and rubber 2 semisynthetic polymers. All these factors will affect the stability andor release properties of the biocidal compounds incorporated although very few studies exist to date that take them into account efrati et al. Many of these smaller molecules are able to diffuse through the material and be released into any liquid or air in contact with the plastic and. By the end of the session the delegate should have understood the following. The examples are high density polythene, polyvinyl chloride, etc. Due to their broad range of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. They reduce the intermolecular cohesive forces between the polymer chains, which in turn decreaset g.
This lesson introduces students to polymers, their properties, and some of the many ways polymers. In basic terms, a polymer is a longchain molecule that is composed of a large number of repeating units of identical structure. Physical properties some physical properties describe how an object responds to mechanical forces. Reviewing of general polymer types, properties and application in. The process by which the polymers are formed is called polymerisation. Polymers are materials with a seemingly limitless range of characteristics and colors.
All the knowledge gained from the large number of existing. A polymer is a high molecular mass compound ranging from 5000 to one million and they are formed by the combination of a large number of one or more low molecular weight compounds. How a polymer additive is used varies depending on polymer and application. Types of polymers different types of polymers and their. A copolymer of vinyl chloride ch 2 chcl and vinylidene chloride ch 2 ccl 2 is sold under the trade name saran. Types of synthetic organic polymers introduction to.
Manufacturers place an spi code, or number, on each plastic product, usually moulded into the bottom. Types of polymers classification of polymers characteristics of polymers properties of polymers streng slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Polyethylene is considered to be as one of the simplest polymer, it has ethene or ethylene as the monomer unit whereas the linear polymer is known as the high density polyethylenehdpe. The type of polymers that result from a condensation polymerization depends on the monomers. Discover different types of polymer and their properties with trp polymer solutions. A primary reason that polymer properties are different is because the chemical compositions. One of the first polymers to be created, it was produced in 1933 by imperial chemical industries using a high pressure process via free radical.
Many kinds of polymers contain small molecules either unreacted monomers, or substances specifically added plasticizers, uv absorbers, flame retardents, etc. The use of plastics materials has increased dramatically throughout the world over the past 50 years, and now stands at roughly 100 billion pounds. These identical structures, we understand as a unit made up of two or more molecules, join together to form a long chain. Polymers make up many of the materials in living organisms, including, for example, proteins, cellulose, and nucleic acids. The raw materials used to produce them can get extinct, and disposing of synthetic polymers is a very difficult and timeconsuming. The type of polymerization mechanism used depends on the type of functional groups attached to the reactants. In simpler crude terms, it has a waxy or slippery touch. Kevlar is a unique polymer in that it is used for bulletproof vests and jackets. Understanding plastics and polymers the different types. Their physical properties are partic ularly important in determining their usefulness, be it as rubber tires, sidings. When you want to apply any type of load on a particular member, you need to know its material properties, density, etc. The polymers obtained by simple chemical treatment of natural polymers to change their physical properties like starch, silicones 3.
Properties limits type of polymer pp ldpe hdpe pc pbt pai r gcm3 upper 0. A listing of some important addition polymers and their monomer precursors is presented in the following table. Both types of polymers exhibit elastic properties along with a wide range of additional useful properties. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Abs polymers can be given a range of properties, depending on the ratio of the. Polymers have many inherent properties that can be further enhanced by a wide range of additives to broaden their uses and applications. Chemists have also learned to synthesize new polymers from simple chemicals, creating a vast array of plastics and synthetic fibers. From the utility point of view they can be classified into three main categories. Properties to choose a material with the best performance for a particular application, we will need to consider the properties of the available materials.
Thus pvdc is widely used to coat pet beer and cider bottles to prevent diffusion of air into these products and hence prolong their. Polymers and their properties introduction basic topics. The barrier behaviour of polymers is not always as good as inorganic materials, but careful selection of impermeable polymers can reduce air penetration to a minimum. Three types of natural polymers are polysaccharides, proteins, and nuclei acids. Smart polymers are polymers that respond to different stimuli or changes in the environment. Polymers are composed of nonmetallic elements, found at the upper right corner of the periodic table. The polymers are substances with a seemingly endless range of features and colors. These are the polymers which can be easily softened repeatedly when heated and hardened when cooled with little change in their properties. As you can see polymers play a huge role in our daytoday lives and their use is wide and varied owing to their unique individual properties. Polymer can have different chemical structure, physical properties. Polymer abbreviation properties uses lowdensity polyethylene.
Condensation polymers form from the step growth polymerization. Polymers classification, types, uses, properties, polymerization. These polymers are found in nature generally from plants and animals sources. The thermoplastic polymers typically are composed of polypropylene, polyethylene, polybutylene, and thermoplastic elastomers. Their numerical estimation and prediction from additive group contributions summarizes the latest developments regarding polymers, their properties in relation to chemical structure, and methods for estimating and predicting numerical properties from chemical structure. The polymers, which occur in nature are called natural polymer also known as biopolymers. Semisynthetic polymers these polymers are obtained from natural polymers by simple chemical treatment to change the physical properties of natural polymers like starch, silicones. Polymers have unique properties which can be tailored according to their intended purpose. The glass transition temperature is also affected by the molecularweightofthepolymerfig. Polymeric materials are noted for their versatility, high resistance to chemicals, outstanding adhesion to a variety of substrates, toughness, high electrical resistance, durability at high and low temperatures, low shrinkage upon cure, flexibility, and the. They are commonly found in a variety of consumer products. For that, in this article, i am exploring the necessary properties of polymers in a detailed manner. Polymers formed by a straightforward linking together of monomer units, with no loss or gain of material, are called addition polymers or chaingrowth polymers. Inert, thermally stable, tough and high tensile strength bottles, pipes, inner insulation dielectric of coax.
Examples polyvinyl chloride pvc and polystyrene and polymethyl methacrylate. Epoxy resins are a family of monomelic or oligomeric material that can be further reacted to form thermoset polymers possessing a high degree of chemical and solvent resistance, outstanding adhesion to a broad range of substrates, a low order of shrinkage on cure, impact resistance, flexibility, and good electrical properties. A primary reason that polymer properties are different is because the chemical compositions of metals, polymers and ceramics are totally different. There are several types of the strength, namely tensile stretching of the polymer, compressional compressing the polymer, flexural bending of the. Although their properties are quite different from. Another way of classifying polymers is in terms of their form or function, varying from additives to other bulk materials e. Properties of polymers, fourth edition incorporates the latest developments in the field while maintaining the core objectives of previous editions. Feb 26, 2012 polymers and their properties introduction basic topics. Types of synthetic organic polymers introduction to chemistry. Thermosetting polymers become permanently hard at elevated temperatures and pressures.
On the basis of their occurrence in nature, polymers have been classified in three types 2. They are found commonly in a variety of consumer products such as honey, glue, etc. Polymers polymers are the giant molecules of chemistry. Linear polymers these polymers consist of long and straight chains. Typical reactions for chain assembling are polyaddition continuous or step wise and condensation polymer ization polycondensation 1 figure 1. Their physical properties are partic ularly important in determining their usefulness, be it as rubber tires, sidings for buildings, or solid rocket fuels. These materials exist in countless form and numbers because of very large number and type of atoms present in their molecule. Use our interactive properties table below to explore by property group, sort, or compare two or more plastic materials. Some of the polymers that have achieved commercial importance and their uses are tabulated in table 1 and some of their important physical properties are listed in appendix 2.
The main thermoplastic polymers and their properties are presented in table1. Ldpe is a thermoplastic made from the monomer ethylene. Synthetic polymers are those which are humanmade polymers. Appropriate use of polymer additives improve many characteristics such as durability, stiffness, clarity, weatherability, resulting in creating a product that has higher value. The properties of pvc can be varied over a wide range by adding plasticizers, stabilizers, fillers, and dyes, making pvc one of the most versatile plastics. Examples are proteins, cellulose, starch, resins and rubber. Typical reactions for chain assembling are polyaddition continuous or step wise and condensation polymerization polycondensation 1 figure 1. Uses of polymers structure, types and characteristics of.
Chapters in part one focus on types of polymers, including temperature, ph, photo, and enzymeresponsive polymers. Introduction to materials science, chapter 15, polymers. The word polymer is derived from two greek words, poly that means many numerous and mer which means units. Thus polymers obtained from only one type of monomers are called homopolymers e. Polymers have many original properties that can be further improved by a deep range of additives to increase their uses and applications. Methods of recycling, properties and applications of.
This type of bonding contrasts with metallic bonding, in which valence electrons are not. Polymers are produced on an industrial scale primarily, although not exclu sively, for use as structural materials. They have always made life easier and more convenient in hundreds of different ways, but they also have a downside. For chemically resistant plastic, view our chemical resistance of plastics chart. Polymers can be made to mimic cotton, silk, and wool fibers. Squeeze bottles, toys, flexible pipes, insulation cover electric wires, six pack rings, etc. Physical and mechanical properties of polymer composites.
Polymer is a generic name given to a vast number of materials of high molecular weight. Nuclei do not have to share all of their valence electrons. Show some common addition polymers and their relevant monomers. Polymers that are not highly crosslinked have properties that depend. The polymer is a long chain molecule which is formed by joining many small molecules called monomers. Different types of plastics and their classification the society of the plastics industry spi established a classification system in 1988 to allow consumers and recyclers to identify different types of plastic. Commercial plastics are known as resins in north america, and are made of polymers. There are three different types based on the structure of the polymers. Some of these materials are of course used as products in their own right, or manipulated. Polymers are all created by the process of polymerization wherein their constituent elements called monomers, are reacted together to form polymer chains i. What are polymers and classification of polymers notes. Polymers are those which consists of repeated structural units known as monomers. The unit substance or substances from which the polymer is obtained is called a monomer. These polymers are found in nature, example plants and animals.
Physical structure of polymers, small vs large molecules, molecular features, some physical technique for studying polymers, molecular sizes and shapes and ordered structures, polymer blends and copolymers, polymer blends and copolymers, regular chains and crystallinity, morphology and motion, morphology morphology and motion. Pdf preparation and properties of stereoregular polymers. Describe how the chemical structure of a polymer relates to its physical properties. Ways of processing them to shape and improving their properties were developed during the victorian era see box 1, but it was not until the growth of the organic chemical industry that the first synthetic polymers were made. Introduction to materials science, chapter 15, polymer structures university tennessee, dept. Physical properties of polymers physical properties of polymers 293 forces between polymer chains polymers are produced on an industrial scale primarily, although not exclu sively, for use as structural materials. Types and properties pdf by mohammed shafi october 22, 2018 may 10, 2020 in this article, i will be explaining the different types of plastics used in our household applications as well as industrial applications in the form of thermoplastics and thermosetting plastics with there properties.
They reduce the intermolecular cohesive forces between the polymer chains, which in turn. Synthetic polymers what are polymers types and uses of. Polymers can be used to produced to mimic cotton, silk, and wool fibers. As an industry leader in polymer solutions, we explain how materials for rubber components are sourced and how various types of polymer could be suited to your application and your industry.
The small buildingblock molecules are called monomers. A secondary coating can be applied using the method. Synthetic polymers are an important part of the modern world. There are polymers made by polymerizing a mixture of two or more. Addition polymers are a type of polymer in which all the monomers are unsaturated or to simply to say are alkenes. During the polymerization process, the double bonds in the alkenes break and they all join together to form a large molecule. The number of synthetic resins which can be made is vast. Methods of recycling, properties and applications of recycled.
Understanding plastics and polymers the different types of. Properties are the observed characteristics of a sample. Polymers can be classified in several different ways according to their structures, the types of reactions by which they are prepared, their physical properties, or their technological uses. Properties of plastics or polymers play a vital role in the field of mechanical engineering. Also, you may want to use our plastic material selection guide or interactive thermoplastics triangle to assist with the material selection process based on your application requirements. Polyester resins are formed from the reaction of dibasic organic acids and polyhydric alcohols.
Synthetic polymers are a mainstay of modern life, but nature also makes polymers. Here when molecules of monomers react to form a bond they replace certain molecules. Cotton tshirts and plastic spoons do not have much in common with. The true molecular nature of materials like natural rubber and synthetics like bakelite was not understood until about. Polymers are huge molecules that are encountered in nature as well as in our modern technology. These polymers have been compounded with modifying or stabilizing additives. Synthetic polymers types and examples polymer uses. Polymers are studied in the field of biophysics, macromolecular science, and polymer science. This article looks at 12 different types of resins and their properties and applications. Examples of such polymers are natural rubber, natural silk, cellulose, starch, proteins, etc.
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