Polymers: Lecture 2 Prepared by Dr Arunima Nayak and Dr Brij Bhushan Classification of Polymers 1. Classification on the bases of source: Natural polymers: These polymers are obtained either from plants or animal and are named as plant polymer e.g. Classification of Polymers. There are several ways of classification of polymers based on some special considerations. There is little interest in small organic molecules based on the monomers. For example Polymers example Polythene Polyvinyl chloride (PVC) Nylon Teflon Bakelite Terylene Cellulose diacetate Vulcanised rubber Starch Melamine formaldehyde resin Polymers Uses Coatings Adhesives Laminates Electrolytes Plastic pipes Films Questions on polymers What are polymers? When the monomers react to form a network, a 3-D structure, then those polymers are known as Network polymers. Properties. received from Ireland after the CA meeting in : December 2007 some additional guidance on . 3. Classification Based on Composition of Polymers: [1] Homopolymer: A polymer resulting from the polymerization of a single monomer; a polymer consisting substantially of a single type of repeating unit. For example; cellulose, starch, proteins, nucleic acids. Polyethylene Classification of Polymers 1. The cross-linking restricts the motion of the chains and leads to a rigid material. Artificial Polymers These monomers are known as straight polymers. The average molecular weight of the polymer molecular. Copolymer: On the other hand, a copolymer is made up of two or more types of re… When monomers react in a manner that branches are formed in the chains of the polymers, then those polymers are known as branched polymers. Polypropene, also known as polypropylene, is made up of monomer propene. All plastics are polymers … The monomer … An elastomer must be above its glass transition temperature, \(T_g\), and have a low degree of crystallinity. polymer,classification of polymers,polymerization,copolymer,polythene.PVC,polystyrene,polyester,polycarbonates,polyamides,nylon6.6,addition ,isotactic This is one of the best Blogs for free tutorials about various parts of chemistry, such as element chemistry, organic chemistry, inorganic chemistry, physical chemistry, analytical chemistry, … 3] Based on Mode of Polymerisation Polymerization is the process by which monomer molecules are reacted together in a chemical reaction to form a polymer chain (or three-dimensional networks). The monomers in these are linked together to form a long chain. 2] Classification Based on Structure of Polymers Classification of polymers based on their structure can be of three types: (i) Linear polymers: These polymers are similar in structure to a long straight chain which identical links connected to each other. For example natural rubber is obtained as latex from rubber trees. These include starch cellulose, proteins, nucleic acids and natural rubber. All about Polymers and polymer chemistry for undergraduate students. cellulose, jute, linen, silk, wool etc. For example;Low density polythene, glycogen, starch. 4. Agitation can speed up this process. Polymers; Polymer chemistry; monomers; polymerisation; example;uses; questions; revision. The dissolving process in polymer is shown in fig below Solubility process. Polymers are classified into three types on the basis of Structure. The small molecules that are used in synthesizing a polymer are called monomers. Based on Structure/Shape of polymer Polymers can be linear, branched, cross linked or networked. Polylactic acid, or polylactide (PLA) is a thermoplastic polyester with backbone formula (C 3 H 4 O 2) n or [–C(CH 3)HC(=O)O–] n, formally obtained by condensation of lactic acid C(CH 3)(OH)HCOOH with loss of water (hence its name). Artificial polymers: They are artificially made in industries for various commercial uses. Derivatives of natural macromolecular polymers per se, e.g. Classification Based on Composition of Polymers: [1] Homopolymer: A polymer resulting from the polymerization of a single monomer; a polymer consisting substantially of a single type of repeating unit. Compositions based on monomers of such polymers are also classified in C08G. Classification of Polymerization Reaction Copolymer - It is called when the polymer formed by at least 2 different monomers along the entire chain. Since the entropy of mixing ΔS is always positive. A hazard ranking model for environmental and human health hazard classifications was developed. Polymers may however still be subject to authorisation and restriction. Source-based nomenclature can be used when the can be monomer identified. The glass transition temperature of polymers determines the temperature at which the polymer mechanical properties of polymers change dramatically, when the glass transition temperature is slightly below room temperature the polymer behaves like an elastic material (elastomer), when the temperature is higher than the glass transition temperature the polymer behaves as a rigid material (thermoset). A copolymer is a polymer derived from more than one species of monomer. These polymers have high melting points and are of higher density. The simple molecules from which polymers are derived are called monomers. [2] Copolymer: When two different types of monomers are joined in the same polymer chain, the polymer is called a copolymer. 1. of monomers join together to form long chains. Addition, Videos and Examples Polymers: Classification, Polymerization, Biodegradable Polymers, Rubber. The close packing results in high densities, tensile strength and high melting and boiling points. derived from proteins or vulcanised oils, are classified in C08H. Examples are proteins, cellulose, starch, some resins and rubber. The building block through which any polymer molecule is built is known as a monomer. • Linear polymers have monomeric units joined end to end in single chains. Among the properties that define the properties of polymers, the most important are: The glass transition temperature of the polymer. Polymerization is the process by which ​monomer molecules ​ are reacted together in a chemical reaction to form a polymer chain (or three-dimensional networks). Polymers are large molecules made up of alike repeating blocks known as monomers. CLASSIFICATION OF POLYMERS : 1.  Polymer is used as a synonym for plastic. Polymers obtained during condensation reaction are called condensation Polymers. Examples are proteins, cellulose, starch, resins and rubber. 6. There may be extensive van der Waals and hydrogen bonding between the chains. The physical properties of the two acidic monomers are con-trasted in Table 1. The urea-formaldehyde resin is a non-transparent plastic obtained by heating formaldehyde and urea. Study Materials Classification of Polymers: Source, Structure, Polymerisation, Examples Types of Polymerization: Condensation vs. The monomers in these are linked together to form a long chain. Due to their complex structures, different behaviours, and vast applications we can, classify polymers based on the following criteria: Polymers based on the Source of Availability . B- Classification Based on the structure of polymers : There are three different types based on the structure of the polymers. • These chains has no any side chains, ex. 2] Classification Based on Structure of Polymers. The polymerization of monomers into copolymers is called copolymerization. This process is slow because of cross-linking, crystallinity or hydrogen bonding. Classification of polymers: Classification based on source of availability: 1. 1. These belong to the polymer families of polyurethanes, polyacrylonitriles, polyvinyl chloride, epoxy resins, and styrenic copolymers. The average molecular weight directly determines both the size of the polymer and its chemical and mechanical properties of the polymer (viscosity, wet, creep resistance, abrasion resistance ...), for example polymers with high average molecular weight materials are very viscous. Quick summary with Stories. Alkenes, vinyl chloride, adipic acid, glycol with two bonding sites act as monomers. Polymer and monomers (Polymers definition) Polymers are high molecular mass substances containing large number of repeating structural units derived from simple molecules. The properties of polymers are strongly influenced by details of the chain structure. Synthetic polymers: 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. Homopolymer consist of only one type of monomers. This process of formation of polymers from respective monomers is called polymerisation. Thus, a co-polymer is obtained when two or more suitable monomers are polymerised together. Based on the type of polymerization, polymers can be classified as: i) Addition polymers: These type of polymers are formed by the repeated addition of monomer molecules. 1.1 Classification of Polymers. Common examples would be … under REACH. Examples: polyethylene, PVC, nylon. Classification of polymers based on their structure can be of three types: (i) Linear polymers: These polymers are similar in structure to a long straight chain which identical links connected to each other. The synthetic polymers can be further classified as these made up of monomers and comonomer units. Polystyrene is an aromatic polymer, naturally transparent, made up of monomer styrene. Therefore, cannot be classified under a single branch. 2] Classification Based on Structure of Polymers. These techniques are based on forcing a polymer solution through a matrix of cross-linked polymer particles at high pressure of up to several hundred bars. Conveniently, all polymers can be assigned to one of two groups based upon their processing characteristics or the type of polymerization mechanism. Based on the ​type of polymerization ​, polymers can be classified as: Polymers are macromolecules having high molecular weights and they are composed of smaller repeating units called monomers. All simple molecules cannot behave as monomers but only those with two or more bonding sites can act as monomers. Nonetheless, manufacturers and importers of polymers may still be required to register the monomers or other substances used as building blocks of the polymer, as these molecules are generally recognised as of higher concern than the polymer molecule itself. Thousands of different polymers have been synthesized and more will be produced in the future. ADHESIVE BONDING. Two very common techniques for measuring the molecular mass of polymers are high-pressure liquid chromatography (HPLC), also known as size exclusion chromatography (SEC), and gel permeation chromatography (GPC). Classification of polymers. Polymers obtained during addition reaction are called addition Polymers. • Linear polymers have monomeric units joined end to end in single chains. Natural polymers: These polymers are found in plants and animals. Classification: Classification Based on Source: [1] Natural Polymers: These polymers are found in plants and animals. The polymers that ranked as most hazardous are made of monomers classified as mutagenic and/or carcinogenic (category 1A or 1B). The small molecules that are used in synthesizing a polymer are called monomers. Polyethylene consist of monomer ethene only. Polymers can be classified by using the backbone of the polymeric chain, type of synthesis, source, monomer, molecular forces, etc. The polymers which are prepared in the laboratory are referred to as synthetic polymers or man-made polymers. These reactions are classified as: Depending on how they are linked or joined (chemical bonds or intermolecular forces) and on the arrangement of the different chains that forms the polymer, the resulting polymeric materials can be classified as: Depending on the chemical composition, polymers can be inorganic such as glass, or they can be organic, such as adhesives of epoxy resin. Poly he a methylene dopamine 4. For very high molecular weight, the solution process takes days or weeks. new clarification of intermediate definition. A polymer formed by direct addition of repeated monomers without the elimination of any molecule is called addition polymer. 8 min. Introduction to Polymer Fibres. Naturally occurring polymers: These occur in plants and animals and are very essential for life. The formation of the polymer chains are produced by different polyreactions that can occur between monomers. 27/05/2008 : Version 2.0 . When monomers react in a manner that branches are formed in the chains of the polymers, then those polymers are known as branched polymers. Classification. The unit substance or substances from which the polymer is obtained is called a monomer. Anything that is made up of same type of Chemical composition which is repeated numerous times can be considered as a polymer. Copolymer: When two different types of monomers are joined in the same polymer chain, the polymer is called a copolymer. The particular form and morphology … Polyethene, PVC, Nylons, polyesters etc. These details include the overall chemical composition and the sequence of monomer units in the case of copolymers, the stereochemistry or tacticity of the chain, and the geometric isomerization in the case of diene-type polymers for which several synthesis routes may be possible. Section 2.1 and 3.1 – Reference to monomers as : intermediate reworded in order to be consistent with . The physical and chemical properties of polymers vary widely, based on their monomers, structures, and additives. [2] Copolymer: When two different types of monomers are joined in the same polymer chain, the polymer is called a copolymer. There are various ways to classify polymers based on source, structure, mode of forming, molecular forces etc. Based on Origin: a) Natural polymers e.g starch, silk and wool. There are a wide range of materials whose composition is based on polymers, all plastics, paint, coatings, adhesives, composites, etc ... these are examples of polymer-based materials we use in our daily life. (i) Copolymers : Molecules which are built up of at least two different kinds of monomer are known as co-polymers. Organic polymers can be also divided into natural polymers such as proteins and synthetic polymers as thermosets materials. Types of Polymer. Most important addition polymers are polymerized from olefins and vinyl-based monomers. Thermosets are strong and durable. For example; Bakelite, melamine formaldehyde resin. Polymers are a huge chain of molecules. For example;High density polythene,PVC, Nylon, Polyester. Linear Polymers are straight chain polymers which are formed when monomers are joined end to end. The simple compounds from which polymers are made, are called monomers. 2) The gel gradually disintegrates into true solution. Whereas monomers are simple molecules which undergo polymerization (a phenomenon in which two or more molecules chemically react to combine and form polymers) in order … Thus the sign of ΔG is dependent on the sign and magnitude of heat of mixing ΔH. Polymers can also be classified based on the type of monomers present in them. These linear chains are closely packed in space. They can be subdivided into two broad classes, depending on the kind of the polymer that they form. Polymer is basically thousands/millions of monomer units or single repeating unit connected in long chains. Polymer nomenclature usually applies to idealised representations; minor structural irregularities are ignored. Polymer is used as a synonym for plastic . This classification includes the following categories; Homopolymer: A homopolymer is made up of only one type of monomer. (iii) Cross-linked polymers or network polymers In such polymers, the monomer units are linked together to form three dimensional network. The polymers that ranked as most hazardous are made of monomers classified as mutagenic and/or carcinogenic (category 1A or 1B). To stretch, the polymer chains must not be part of a rigid solid - either a glass or a crystal. Some examples of the synthetic polymers are polyethylene, polystyrene, PTFE synthetic rubber, nylon, PVC, bakelite, teflon, orion, etc. Examples: polyethylene, PVC, nylon. Depending on the repetition or variety of monomers, polymers are classified as: Homopolymer - It is called when the polymer formed by the same monomer throughout its chain. Among the other properties that can be modified based on these factors include solubility in and other solvents, melting point, flammability, color, hardness, transparency, film thickness, wetability, surface friction, moldability, and particle size—the list goes on. The process of converting monomers to polymer is called polymerization. A simulated skeletal structure of a network polymer with a high cross-link density is shown below. Polyvinyl chloride 2. Monomers that participate in condensation polymerization have a different stoichiometry than monomers that participate in addition polymerization: This nylon is formed by condensation polymerization of two monomers, yielding water. 1. For example; Cellulose diacetate, Vulcanised rubber. Polymer means many monomers. ADHESIVE & GLUE | For reasonably non polar molecules and in the absence of hydrogen bonding ΔH is positive. On the basis of monomers On the basis of the monomers polymers are classified into two types namely Classification of Polymer based on Structure. These polymers have high The process by which the polymers are formed is called polymerisation. The process in which monomers are all linked together to form the long-chain polymers is called a polymerization reaction or polymerization process. Homopolymer: A homopolymer is made up of only one type of monomer. These are natural polymers with some modifications. The Polymers prepared in laboratory are called synthetic Polymers. 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.  The word POLYMER comes from the Greek words poly means many and mer means parts. 55 plastic polymers were ranked based on monomer classifications, and assessed. This usually implies that the polymer is made from all identical monomer molecules. Working-up, general processes of compounding and after-treatment are covered by subclass C08J. Based on Source: Under this type of classification, there are three subcategories. what needs to be done for notified polymers has been added (4 pages). Can have more than one type of repeat unit. 1. The polymers are defined as macromolecules composed of one or more chemical units (monomers) that are repeated throughout a chain. Section 3.2.1.2 - Based on the comments . Solubility Parameter A polymer is soluble when the Gibbs free energy of mixing i.e ΔG = ΔH - TΔS is negative. Polyvinyl chloride (PVC) contains monomer. Monomers and their dimer counterparts are archetypal plasmonic structures and a versatile theory could rightfully be expected to offer new insights for both individual monomers as well as for ass… The functionality of monomers depends upon the number of bonding sites in monomer. Based on Number of Monomers: Polymers can be homopolymer or copolymer when the number of monomers are one and two respectively. Classification of Polymers Polymers are classified into different types on the basis of monomers, source of availability, structure,mode of synthesis. These are expected to be quite hard, rigid and brittle. The word ‘polymer is coined from two Greek words ‘poly’ means ‘many’ and ‘mer’ means ‘unit or part’. There may be extensive van der Waals and hydrogen bonding between the chains. Fig.4. Polyurethanes, polyacrylonitrile, PVC, epoxy and styrenic copolymers ranked as most … On the basis of the monomers polymers are classified into two types namely. Monomers react with each other in end to end fashion such that they form linear or straight chains of polymers. Monomer – a molecule that can be polymerized to form a polymer. Polymers can also be classified based on the type of monomers present in them. Research highlights Environmental and health hazards of chemicals in polymer production were identified. These monomers are known as straight polymers. The transformation of ethene to polythene and interaction of hexamethylene diamine and adipic acid leading to the formation of Nylon- 6, 6 are examples of two different types of polymerisation reactions. Emulsion Polymers are tremendously versatile! Nylon 6,6 12. Classification of polymers based on their structure can be of three types: (i) Linear polymers: These polymers are similar in structure to a long straight chain which identical links connected to each other. This classification includes the following categories; 1. ADHESIVES | The synthetic polymers can be further classified as these made up of monomers and comonomer units. INTRODUCTION | 1. They have vast chemistries and provide low cost, low emissions, zero VOC, good shelf-life, freeze-thaw stability, and potential sustainability in many coating formulations.Due to these benefits, the use of emulsion polymers is increasingly used in paints and coatings serve growing needs in diverse sectors and applications. Polystyrene 3. 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