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Types Of Addition Polymerization

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Chain-growth polymerization reaction is one of two processes to convert a monomer molecule into a polymer. Chain-growth polymerization reaction is a polymerization technique where unsaturated monomer (means containing double and triple bonds in their structural formula) molecules add onto the active site on a growing polymer chain one at a time.           Depending on this active site present on the growing polymer chain, there are three types of addition polymerization: free radical polymerization , ionic polymerization , and coordination polymerization . Out of which, coordination polymerization is rarely observed, so we will not study about it. Thus, Let us study briefly about all these types of addition polymerization reactions; (A) Free radical polymerization – Free radical polymerization is defined as a type of addition polymerization in which the active centres are free radical. It is denoted as "M•". Since free radical polymerization is a type of addition polymerizati

Thermoplastic Vs Thermoset Polymers

Polymerization is a process in which thousands of smaller molecules called "monomers" join together to form larger molecules called "macromolecules/polymers". Polymers have higher molecular weight than monomers as they are formed by joining these monomer molecules.  Several different categories of polymerization reactions exist, but the most notable of which are: step-growth polymerization and chain growth polymerization. In this post, we will learn about two types of polymers which are classified on the basis of thermal properties and molecular forces present between them. These two types of polymers are Thermoplastic and Thermosetting polymers.  Thermoplastic polymers – Thermoplastic polymers or Thermo-softening plastics polymers are long chain polymers in which the polymeric chains are held together by the weak intermolecular forces (or Van-der waals forces).  These types of polymers are formed by the addition polymerization or chain-growth polymerization reactio

Step-Growth Polymerization Or Condensation Polymerization

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In this article, we will learn about Step-growth polymerization reaction and it's characteristics in details. And also the examples of polymers formed by this step-growth polymerization process Step-growth polymerization also known as condensation polymerization is one of the two processes of producing large molecular weight (polymer) compound from low molecular weight compound (monomers).  So first of all we should know about polymerization technology, what is polymerization?  Let's understand it.......... In polymer chemistry, a reaction by which smaller molecules (called monomers) react with each other to form a larger molecule (called polymers), is called " Polymerization ". Polymers are the high molecular mass compounds.  Condensation Polymerization or Step-growth Polymerization " Step-growth polymerization reaction " also known as " Condensation Polymerization reaction " .  In condensation polymerization, polymer molecules are formed by indep

Chain Growth Polymerization Or Addition Polymerization

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Polymerization is a process in which thousands of smaller molecules called "monomers" join together to form larger molecules called "macromolecules/polymers". They have high molecular weight. Several different categories of polymerization reactions exist, but the most notable of which are: step-growth polymerization and chain growth polymerization.  Chain-growth Polymerization   Chain-growth polymerization reaction is one of two processes to convert a monomer into a polymer.  " Chain-growth polymerization reaction is a polymerization technique where unsaturated monomer (means containing double and triple bonds in their molecular formula) molecules add onto the active site ( It can be radicals, positive ions and negative ions etc.) on a growing polymer chain one at a time ". Chain-growth polymerization reaction also known as Addition polymerization reaction. Monomers used in chain growth polymerization reaction; E thylene/ethene [CH₂=CH₂] Propylene [CH₃–CH=

Poly-Dispersity Index Of Polymers

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First of all we should know what are polymers and how they are defined???? " A polymers is defined as a large molecule (or macromolecule), formed by joining together thousands of smaller molecule units by chemical bonds (or covalent bonds) ".  These smaller molecules that interact with each other to form a larger molecule are called " Monomers ".   To understand how the molecular weight is distributed within polymers, we study about the poly-dispersity index. " The polydispersity index measures the distribution of molecular mass in a given polymer sample ". The molecular weight of a polymer is defined as the sum of the atomic weights of each atom in the molecules, which is present in the polymer. Due to the different chain lengths of polymers, we cannot directly measure the molecular weight of the polymer. So we calculate the average molecular weight of the polymer on two basis- " Number average molecular weight "  and "Mass average molecul

Addition Vs Condensation Polymerization

In polymer chemistry, a reaction by which smaller molecules (called monomers) react with each other to form a larger molecule (called polymers), is called " Polymerization ". There are two types of Polymerization processes in polymer chemistry and these are- (1) Addition Polymer (2) Condensation Polymer Let's compare them one by one based on their formation, molecular weight, functionality, no. of monomer used, etc. Comparation between Addition and Condensation polymerization (1) Addition polymerization is the process of adding unsaturated monomers to form an addition polymer. While Condensation polymerization is the process of combining monofunctional, bifunctional and trifunctional monomers to form a condensate polymer. (2) No formation of by-products in addition polymer whereas by-products are formed in condensation polymerization. (3) In addition polymerization, molecular weight of a resultant polymer is a multiple of monomer's molecular weight whereas in condensa

Polymer Techniques/ Polymerization Process

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The word polymer is a combination of two Greek words-                Poly means 'many'             Or Mers means 'parts of unit     ☆ Poly + Mers ➝ many parts of unit In polymer chemistry;  Polymerization is a process in which thousands of smaller molecules called " monomers " join together to form larger molecules called " macromolecules/polymers ". They have high molecular weight. Or " It can also be defined as the fundamental process by which low molecular weight compounds are converted into high molecular weight compounds ".        Polymerization Processes Several different categories of polymerization reactions exist, but the most notable of which are: step-growth polymerization and chain growth polymerization.  (a)  Chain growth polymerization / Addition polymerization " Chain-growth polymerization reaction " also known as " Addition polymerization reaction ". In this polymerization reactions, monomer molecules bond t

Polymer Classification

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A polymers is defined as a large molecule (or macromolecule), formed by joining together thousands of smaller molecule units by chemical bonds (or covalent bonds). Classification of Polymers • Based on origin or source There are three types of polymers based on the source (or origin) and these are; (A) Natural polymers Natural polymers are those polymers that occur naturally in plants or animals. Example of these polymers are proteins, cellulose, starch, resins and rubbers etc. (B) Semi-synthetic polymers Semi-synthetic polymers are polymers that are obtained by artificially modifying natural polymers in the laboratory. Example of these polymers are cellulose acetate, cellulose nitrate, hydrogenated natural rubber, etc. (C) Synthetic polymers They are also known as man-made polymers. These polymers are synthesized artificially in the laboratory by humans. Example of these polymers are Polyethylene, synthetic fibres, nylon-6, Buna-s, polyesters, etc. " Plastics are the most common

Polymer Examples

A polymers is defined as a large molecule (or macromolecule), formed by joining together thousands of smaller molecule units by chemical bonds (or covalent bonds). These smaller molecules are known as monomers. Example of polymers and their monomers ; (1) Poly-ethene, also called polyethylene, is composed of ethene or ethylene monomer. Commonly called "Plastic". (2) Similarly, Poly-propene, also called poly-propylene, is composed of ethene or ethylene monomer. (3) Polystyrene, aromatic polymers, is composed of styrene monomer. (4) PVC (or Poly-vinyl chloride), is composed of vinyl chloride monomer. (5) Teflon, or PTFE➛ Poly-tetrafluoroethylene, is composed of TFE (or tetra-fluoro-ethylene) monomer. (6) Butyl Rubber, sometimes called as "butyl" only, is composed of Isobutylene monomer. (7) PMMA (or Polymethyl-methacrylate) whose monomer unit is methyl-methacrylate. It is more transparent than glass. (8) Nylon-6, belongs to polyamide family, is composed of Caprolacta

What do you understand by Polymer?

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Polymers forms a very important class of materials without which life seems very difficult. They are all around us in everyday use. Polymers are very large molecules which are very essential for our existence. It is a main component of our food (starch, protein, etc.), our clothes (polyester, nylon, etc.), our home (wood cellulose, alkyd paint, etc.), and our body (nucleic acid, protein, etc.) Polymers   The word polymer is a combination of two Greek words- " Poly+Mers "  Poly means 'many' Or Mers means 'parts of unit'          Poly + Mers ➝ many parts of unit Thus, " A polymers is defined as a large molecule (or macromolecule), formed by joining together thousands of smaller molecule units by chemical bonds (or covalent bonds) ".               These smaller molecules that interact with each other to form a larger molecule are called " Monomers ". In polymer chemistry, a reaction by which smaller molecules (called monomers) react with e

Introduction To Polymer

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Polymers forms a very important class of materials without which life seems very difficult. They are all around us in everyday use.  Polymers are very large molecules which are very essential for our existence. It is a main component of our food (starch, protein, etc.), our clothes (polyester, nylon, etc.), our home (wood cellulose, alkyd paint, etc.), and our body (poly (nucleic acid), protein, etc.).                     Polymers are found in abundance on the Earth's surface; either in nature or artificially prepared.  For example; We use plastic bags, cards, paper, wood, clothing, paint and endless items that contain the basic chemical composition of polymers.  Human and animal bodies are mainly made up of proteins and these proteins are the building blocks of life. They are also polymers.  Definition The word polymer is a combination of two Greek words- "Poly+Mers"                  Poly means 'many'             Or Mers means 'parts of unit'     ☆ Poly