Chakravarty university college of technology, osmania university, hyderabad email. 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. Macromolecules or polymers are found in the human body, animals, plants, minerals and manufactured products. Uses of polymers polypropene has a broad range of usage in industries such as stationery, textiles, packaging, plastics, aircraft, construction, rope, toys. Ring opening polymerization can occur without the loss of any small molecules. Addition polymers from alkene monomers or substituted alkene monomers are the biggest groups of polymers in this class.
Some of the polymers that have achieved commercial importance and their uses are tabulated in table 1 and some of their. Polymers encompass a broad category of large molecules created by the bonding of many similar constituent molecules. The following are four different types of copolymer struc tures that. Molecules can be made of single types of atoms or of different types. In basic terms, a polymer is a longchain molecule that is composed of a large number of repeating units of identical structure.
They are a main constituent of our food starch, protein, etc. Polyvinyl chloride is used in furniture and clothing and has recently become famous for the construction for doors and windows. Polymers polymers are the giant molecules of chemistry. Uses of polymers structure, types and characteristics of. Pdf on sep 1, 2012, jelena milisavljevic and others published tensile testing for different types of polymers find, read and cite all the research you need on researchgate. Introduction to materials science, chapter 15, polymer structures university tennessee. Examples of saturated all bonds are single ones hydrocarbon molecules. For example, the oxygen in the air is made of two oxygen atoms o 2, but water is made of two hydrogen atoms and one oxygen atom h 2 o. In the twentieth century most polymer data were represented by using d,i pairs such as the data shown on the bottom. Condensational polymers substances formed from a combination of two different bifunctional or trifunctional monomers with the elimination of small molecules such as alcohol or water. There are many different kinds of polymer materials, including cellulose, natural or biopolymers, silicones and plastics. Pdf on may 28, 2008, gary wnek and others published polymers find. The chapter details different components in the manufacturing of pu polymers, composites, and nanocomposites. External stressfree reversible multiple shape memory polymers.
Examples are proteins, cellulose, starch, resins and rubber 2 semisynthetic polymers. A variety of other natural polymers exist, such as cellulose, which is the main constituent of wood and paper the list of synthetic polymers, roughly in order of worldwide. Linear polymers these polymers consist of long and straight chains. The small buildingblock molecules are called monomers. A polymer is a macromolecule which consists of small molecular units that are repeated over and over again to form a long chain.
Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation. Harris wright state university, dayton, oh 45435 polymers are extremely large molecules that are essential to our very existence. Polymers are composed of nonmetallic elements, found at the upper right corner of the periodic table. The amount of liquid that can be absorbed depends on the ionic strength of the solution the total concentration of positive and negative ions in the solution. A terpolymer is a copolymer which contains three types of repeat units. Polymers usually are prepared by two different types of polymerization. From the utility point of view they can be classified into three main categories. Discover different types of polymer and their properties with trp polymer solutions. Class 12 chemistry revision notes for chapter 15 polymers free pdf download. Copolymers polymers which are formed by combining two different monomers in alternating fashion are called copolymers. Introduction to materials science, chapter 15, polymer structures university tennessee, dept. Polymer synthesis there are two major types of polymerization methods used to convert small molecules monomers into polymers. Lowdensity polyethylene ldpe is produced by free radical polymerization at high temperatures 200c and high pressures above atm. Synthetic polymers are humanmade polymers derived from petroleum oil.
Polymer blend, homogenous down to the molecular level, associated with the negative value of the free energy of. Types of polymers different types of polymers and their. Polymer chemistry, sixth edition nanjing university. Introduction to materials science, chapter 15, polymer structures. 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. Polymers made up of with different type of monomers are called. The objective of this work was to determine the influence of washing and sterilization under real hospital conditions on properties of microbial barrier offered by polyurethane coated fabrics used in surgery and for wrapping sterile items.
The number of synthetic resins which can be made is vast. 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. A polymer is analogous to a necklace made from many small beads monomers. Polymer nomenclature is generally based upon the type of monomer residues comprising the polymer. There are two major types of polymerization methods used.
These different elements in the monomers contribute to the different properties of the different types of plastics. There are three different types based on the structure of the polymers. The phenomena researched in this field are fundamentally the consequence of structures and dynamics. 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. The back bones of common synthetic polymers such as polythene, polystyrene and poly acrylates are made up of carboncarbon bonds, whereas hetero chain polymers such as polyamides, polyesters, polyurethanes, polysulfides and polycarbonates have other elements e. Below, the covering of the cable is a block copolymer of the two alkenes, giving a very tough material with rubberlike properties.
Polymers types, classification, properties, and uses of polymers what are polymers. Apr 09, 2020 polymers encompass a broad category of large molecules created by the bonding of many similar constituent molecules. The updating of analytical, physical, and spectral characterization techniques. A chemical reaction forming polymers from monomers is called polymerization, of which there are many types. Ncert solutions for class 12 chemistry chapter 15 polymers. The aim of this study was to assess the range of possible sheet plastinate modifications and how the resulting multiple polymer plastinates can fulfil. Lec1 introduction to polymer blend polymer blend pb. Stressstrain behavior of different types of materials. If you want to, you can use the name of the title of this section, how can different polymers be identified. It also includes new developments of polymer science which are considered as hot topics of functional polymers like smart or intelligent polymers, light emitting polymers, conducting polymers.
Classification of polymers based on their structure can be of three types. Some other titles you might consider are listed here. Copolymerization 16 copolymerization is defined as the process of combining two polymers that are different v. Polymers products that are commonly referred to as plastics by the general public are known to chemists as polymers. More polyethylene is produced each year than any other plastic. All chapter 15 polymers exercises questions with solutions to help you to revise complete syllabus. Polymers are formed by linking monomers through chemical reactioncalled polymerization. These identical structures, we understand as a unit made up of two or more molecules, join together to form a. If you are new to university level study, find out more about the types of qualifications we offer.
The principle that the basic concepts that apply to one grouping of polymers apply to all the other types of polymers is emphasized. Phase transitions in polymers play a central role not only in the scientific understanding of condensed matter, but also in their technological development. Thus pvdc is widely used to coat pet beer and cider bottles to prevent diffusion of air into these products and hence prolong their useful shelflives. Polymer is defined as a chemical substance of a high molecular mass formed by the combination of a large number of simple molecules, called monomers. Size shape structure introduction to materials science, chapter 15, polymer structures university tennessee, dept. The macromolecule can have different end units, branches in the chain, variations in the sequence of the monomers, and different monomers repeated in the same chain which leads to the large. Again there are four types of addition polymerizations which are. The reaction occurs in such a manner that a new free radical or cation or. The word polymer is derived from two greek words, poly that means many numerous and mer which means units. A common name for many synthetic polymer materials is plastic, which comes from the greek word plastikos, suitable for molding or shaping.
Polymers introduction ppt free download as powerpoint presentation. There are several types of the strength, namely tensile stretching of the polymer, compressional compressing the polymer, flexural bending of the. It is possible to look at polymerization in at least two different ways. Free pdf download of ncert solutions for class 12 chemistry chapter 15 polymers solved by expert teachers as per ncert cbse textbook guidelines. Linear polymers on structure in these polymers monomers are linked with each other and form a long straight chain. Chemistry notes for class 12 chapter 15 polymers the word polymer has a greek origin. A primary reason that polymer properties are different is because the chemical compositions of metals, polymers and ceramics are totally different. 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. Thermosets are made by mixing of two components a resin and a harder which react and harden, either at room temperature or on heating the resulting polymers is usually heavily crosslinked. In this lesson, learn about the process of polymerization. Manufacturers place an spi code, or number, on each plastic product, usually moulded into the bottom. They are found commonly in a variety of consumer products such as honey, glue, etc. Usually two different monomer combine with the loss of a small molecule, usually water. Aug 22, 2019 combining different polymers in one plastinate instead of using one plastination polymer alone can result in improved specimens for exhibitions and teaching including hands.
B classification based on the structure of polymers. The permeability and durability of the microbial barrier were. 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. Accordingly, a series of innovative approaches are proposed for the material design and preparation.
Polymer materials are often created or harvested for a specific purpose depending on the type. In addition polymerization all of the atoms of the monomer molecules become part of the polymer. Lec1 introduction to polymer blend types of polymer blends. Figure 3 different types of copolymer have different properties. These polymers are similar in structure to a long straight chain which identical links connected to each other. Mixture of at least two macromolecular substances, polymers or copolymers, in which the ingredient content is above 2 wt%. So let us study about condensation and addition polymerization. All chapter 15 polymers exercises questions with solutions to help you to revise complete syllabus and boost your score more in examinations. A polymer which contains only a single type of repeat unit is known as a homopolymer, while a polymer containing two or more types of repeat units is known as a copolymer. 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. Class 12 chemistry revision notes for chapter 15 polymers. Some important examples of these substances are discussed in the following sections. Explore the two major types, common polymers, and some of the chemistry involved with this biologically and commercially important. Polymers are classified in a number of ways depending upon one criterion or the other as described below.
The present work is focused on developing external stress free twoway triple shape memory polymers smps. The different types of glycols, isocyanates, and catalysts that are used for the synthesis of different polyurethanes are discussed. Combining different polymers in one plastinate instead of using one plastination polymer alone can result in improved specimens for exhibitions and teaching including hands. Natural polymers three types of natural polymers are polysaccharides, proteins, and nuclei acids.
The condensation polymers are formed by repeated condensation reaction between two different bifunctional or trifunctional monomeric units. For the love of physics walter lewin may 16, 2011 duration. On the basis of source or origin, the polymers are classified into two types. Polymers found in nature, mostly in plants and animal sources, are called natural polymers. A polymer is a large molecule or a macromolecule which essentially is a combination of many subunits. Polyurethane prepolymers carrying crystalline polytetrahydrofuran ptmeg and poly. Copolymers consist of two or more different mer units.
The highdensity polymer hdpe is obtained using zieglernatta catalysis at temperatures below 100c and pressures less than 100 atm. Sep 26, 2012 for the love of physics walter lewin may 16, 2011 duration. Polymers usually are prepared by two different types of polymerization reactions addition and condensation. Here the addition polymer forms by addition of atoms with a free electron in its valence shells. The macromolecule can have different end units, branches in the chain, variations in the sequence. Copolymers composed of different mers copolymers, polymers with at least two different types of mers, can differ in the way the mers are arranged. You are perhaps already aware of various polymers such as pvc, nylon etc. Introduction to materials science, chapter 15, polymers. You will notice although all these are polymers, they have very different physical appearance and properties. In these polymerisation reactions, the elimination of small molecules such as water, alcohol, hydrogen chloride, etc.
Synthetic polymers are a mainstay of modern life, but nature also makes polymers. At a transition point, both structures and dynamics exhibit sudden changes. Traditionally, the industry has produced two main types of synthetic polymer plastics and rubbers. On the right, the medical vials are made of a random copolymer of ethene and propene which give a flexible and clear material. Three types of natural polymers are polysaccharides, proteins, and nuclei. This is due to the difference in their monomers and their polymerization.
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