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degree of polymerization ppt

High degree of polymerization 3. If we divided , the molecular weight of polymer by the molecular weight of monomer , then we can get the degree of polymerization . DP No ' N Thus, the degree of polymerization can be expressed by DP = No N0d-P) i 1-P Consider a reaction that can be pushed to 90% completion. High molar mass polymer are produce … In practical conditon, using this method is complicated and expensive due to the necessity of disasembling the transformer. 3- modulus of elasticity of the material. Two-Dimensional Polymerization of Lipid Bilayers: Effect of Lipid Lateral Diffusion on the Rate and Degree of Polymerization. Polymer, molecular weight, property, polymerization, effect of molecular weight, chemical engineering, average molecular weight, degree of polymerization, injection molding, extrusion, polydipersity Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. They are the vital links between generation and transmission. Degree of Polymerization. The reaction mixture in line 4 of Table 2.1 is characterized by a number average degree of polymerization Nn = 10/3 = 3.3, with only 30% of the functional groups remaining. ! solid having a degree of polymerization n ranging from two to greater than six. • Polymerization in the aqueous phase is insignificant due to the low monomer concentration. 1. General Comments on Chain Reactions! •High degrees of polymerization ( molecular weight) are obtained only at high degrees of conversion of monomer Two sites (AB or AA + BB) give a linear polymer chain - + Polycarbonate via condensation of bisphenol A and phosgene; an example of an AA + BB polymerization •Non-living, except in a few cases (e.g., Yokozawa) Polyacrylonitrile > 2000. Combination 2. Synthetic fibers are created by extruding fiber forming materials through spinnerets into air and water, forming a thread. We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. 4- type magnitude direction of masticatory forces applied to restoration . Eq. Polymerization is possible only if ∆G < 0 for the transformation of monomer to polymer. The difference in Tg and Tm between the first polyester (completely aliphatic) and the two nylon polyamides (5th & 6th entries) shows the effect of intra-chain hydrogen … Anionic addition polymerization is a form of chain-growth polymerization or addition polymerization that involves the polymerization of monomers initiated with anions. Thus, the average degree of polymerization depends on the monomer and solvent concentration and on the velocity constants of radical formation, chain termination and chain transfer. Solution polymerization | PowerPoint PPT presentation | free to view . … M- concentration of all anions in the system M concentration of the monomer C concentration of the initiator n the number of anions that an initiator molecule produces. 7 MW in Living Anionic Polymerization Poisson Distribution Narrow distribution 8 Typical Products. If you continue browsing the site, you agree to the use of cookies on this website. POLYMERS Introduction to Polymers 2 3. Small yield per reactor volume 6. Degree of polymerization The Degree of polymerization (n or N) is defined as 10 the number of monomeric units in a macromolecule or polymer or oligomer molecule. Degree of polymerization ≡ number of monomer units or structural units incorporated in polymer chain = pn 2 n u n p M M ⋅ = where M u = molecular weight (MW) of individual repeat units Can also have a—b monomers: e.g. The degree of polymerisation can be defined as the frequency of repeating units present in a polymer. POLYMER SCIENCE. Chemical Composition of Silk Fiber, Cotton Fiber & Wool Fiber. The degree of polymerization will increase steady during the whole polymerization process. The polymerization is reversible and, on strong heating, the polymer reverts to cyclopentadiene. When we keep adding monomers to obtain a large chain, such a process is also called as the chain growth polymerization. We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. the degree of polymerization 2. • To develop expressions for the average degree of polymerization and molecular weight distribution for anionic polymerization. There are two basic types of polymerization, chain-reaction (or … Addition polymerization: This is the type of polymerization in which the molecules of a similar monomer or different monomer add up together on a large scale to form a polymer. 11. Propagation proceeds through an alkoxide (anionic polymerization) or an ozonium (cationic polymerization): (1.4) (1.5) Chain transfer and complex termination steps arrest the chain propagation … moles of P*; P: number-average degree of polymerization of the polymer obtained at reaction time t; f([l), g (tm) and u (tn) increase with increasing tl, tm and tn. Failure of a Transformer leads to loss of Revenue besides affecting reliability of power supply to consumers. Often anionic polymerization involves living polymerizations, which allows control of structure and composition. Place 3.0 mL of liquefied phenol and 10 mL of 37% (by weight) aqueous formaldehyde solution in a 25 mL round-bottom flask. unlike conventional … CASE 1 ; Mono-disperse Polystyrene Gel Permeation Chromatography (GPC) standard. Semester 1 2007/2008 Fisika Polimer AriadneL. Solvent may terminate the growing polymer chain, leading to low molecular weight polymers 4. PRESENTED BY: KANTILAL B. NARKHEDE M.PHARM.1st SEMESTER DEPT. Clipping is a handy way to collect important slides you want to go back to later. Polymers and Polymerizations Polymers are macromolecules built up by the linking together of large numbers of much smaller molecules. Lecture 2.0 Polymerisation - Free download as Powerpoint Presentation (.ppt), PDF File (.pdf), Text File (.txt) or view presentation slides online. Now customize the name of a clipboard to store your clips. The type of reaction has many manifestations, but traditionally vinyl monomers are used. of Chemistry. Initiation, propagation, and termination reactions have different rates and mechanisms. M is the molecular weight of the polymer, DP is the degree of polymerization and the M 0 is the formula weight of the repeating unit. It is calculated as the ratio of molecular weight of a polymer and molecular weight of the repeat unit. The … PowerPoint Presentation : Suspension polymerization most commonly used as industrial manufacturing method in order to get polymer for forming material such as polystyrene, polymethylmethacrylate , polyvinyl acetate, polyvinyl chloride, because a polymer with a high degree polymerization is obtained with the polymerization and generated polymer isolation is easy. If you continue browsing the site, you agree to the use of cookies on this website. Organic chemist friends of ours are happy to get reaction yields of … A key characteristic … Nylon 6,6-200. Polymerization of HbS and diGEE-HbS was carried out in 1.8 M potassium phosphate buffer, pH 7.2. The expressions for Rp in cationic polymerization (Eq. Transformer Oil and Degree of Polymerization of Solid insulation Sanjay.G.Patki, S.G.Patil, Jaspal. S. Wadhwa, The Tata Power Company Limited, Mumbai email: jwadhwa@tatapower.com Abstract - Power Transformers are the most vital components in a sub-station / Receiving station. solid having a degree of polymerization n ranging from two to greater than six. The degree of polymerization (DP or Xn) is defined as the number of monomer units in the polymer. Polyester (PET)- 100. Abstract: Degree of polymerization (DP) is thought to be a good index to determined deterioration level of insulation paper in power transformers. In this paper a new method to estimate DP from load and temperature histories is … Now customize the name of a clipboard to store your clips. Introduction to Polymers 3 4. Gel effect. When the temperature increases, the rate of polymerization increases, but the degree of polymerization decreases as shown in Fig. large molecule or a macromolecule which essentially is a combination of many subunits Condensation Polymerization of Phenol and Formaldehyde: Bakelite Caution! The degree of polymerization is unchanged and still described by Eq. In addition polymerization, the monomers add to one another in such a way that the polymer contains all the atoms of the starting monomers. Let RMe be an organometalic compound such as butyl lithium (LiC 4 H 9) that initiates polymerization and M a monomer, then the individual steps can be … The process of linking the repeating units is termed as polymerization . By varying the polymerization temperature, there is big effect on the rate and degree of polymerization . Many natural materials—such as proteins, cellulose and starch, and complex silicate minerals—are polymers. anionic chain polymerization, and boron trifl uoride complexes, complex aromatic salts of Lewis acids such as diaryl iodonium, triarylsulfonium, or arene diazonium for cationic chain polymerization. Chain transfer. The requirements for a separate solvent recovery step Suspension … This is the primary feature of polymer that describes its physical properties as well. The degree of polymerization can be calculated by using the following relationship if a molecular weight of a polymer molecule is known. Malaviya National Institute Of Technology Jaipur, Polymer science: preparation and uses of polymers, No public clipboards found for this slide. High rates of polymerization 2. The polymerization reaction in many chemical compounds may occur through a variety of reaction mechanisms that differ in complexity because of the presence of the functional groups in the reactants as well as due to their inherent steric effects. Viscose Rayon- 150-350. Wool- 60,000-100,000. Polymerization is the process by which monomer molecules are reacted together in a chemical reaction to form a polymer chain (or three-dimensional networks). Some Condensation Polymers. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. 1. In the absence of chain transfer the expression above can be written as . The dispersity of the polymer must be < 1.5. For example, if a—a is a diacid and b—b is a diol: from diacid from diol. The degree of polymerization is the number of mono meric units in a macromolecule or polymer molecule . See our Privacy Policy and User Agreement for details. Compared to step-growth polymerization, living chain-growth polymerization shows low PDI, predictable molecular mass and controllable … DP is defined as the number of monomeric units in a polymer. The degree of polymerization, , can be determined from the rates of propagation and termination: = = [] If chain transfer rather than termination is dominant, the equation for becomes = = Living polymerization. Heterogeneous polymerization a) Suspension b) Emulsion 1.. Thus, the proportion of termination to propagation increases substantially with increasing free Polycyclopentadiene molecules have two different kinds of double bonds for end groups and a complicated backbone of saturated fused rings. • Polymerization mainly occurs in the micelle interiors due to: • high monomer concentration • high surface/volume ratio • presence of interface for organic monomer and water-soluble initiator • During polymerization, monomer is replenished by diffusion from droplets through the solution to micelles. Disproportionation 3. Nevertheless, the polymer clearly forms by a step-growth process. Synthetic polymers: nylon, poly-ethylene, poly-styrene Biological polymers: DNA, proteins, carbohydrates Methods for making polymers Addition polymerization and condensation polymerization Addition polymerization: monomers react to form a polymer without net loss of atoms. A new method of light-powered dissipative supramolecular polymerization is established, in which supramolecular polymerization is implemented in the far-from-equilibrium state. CONTENT: Introduction Types of Polymer Classification Polymerization Structure & Properties Crystallinity Glass Transition Temperature Pharmaceutical Applications INTRODUCTION Definition : A polymer is a large molecule … There are 3 mechanisms of termination: 1. Example PMMA ADVANTAGE Advantage of the high concentration of monomer result in 1. CASE 2 . Radical polymerization shows a half-order dependence of Rp on Ri, while cationic polymerizations show a first-order dependence of Rp on Ri. Silk Fibre Structure. Degree of polymerization. V.S.Saravana Mani, Head& Asso.Prof, Dept. 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. • To emphasize the utility of anionic and living polymerizations in the synthesis of block copolymers. techniques Process conditions: Homogeneous polymerization: a) Bulk b) Solution 2. For reducing the disadvantages of bulk polymerization, the process can be carried out in a solution. See our User Agreement and Privacy Policy. The degree of polymerization, DP is the original number of molecules divided by the remaining number of molecules and approaches a number equal to the original number of molecules as N approaches one. Polymerization, any process in which small molecules known as monomers combine chemically to produce a very large chainlike or network molecule, called a polymer. Cotton- 4000-10,000. Power transformers are ' the heart of substation'. Formaldehyde is a suspected carcinogen and should also be handled with gloves. Aims: We assessed to what extent fructans of different degrees of polymerization (DP) differ in their prebiotic effectiveness towards in vitro microbial communities from the proximal and distal colon. Usually at least 100 monomers must be combined to make a product that has certain unique physical properties. This Marginal Gap Creates An Increasingly Deteriorating Conditions For … Emulsion polymerization BULK POLYMERIZATION The simplest method of polymerization where the reaction mixture contains only the monomer and a monomer soluble initiator. V.S.SARAVANA MANI At an average degree of polymerization of 10, less than 1 weight percent of the monomer remains. The polymerization of deoxy protein was initiated by the temperature jump from 0 to 30°C, and the extent of polymerization was monitored by measuring the absorbance of turbidity at 700 nm. 8.45. at any degrees of polymerization, the influence of chain transfer on the average degree of polymerization and on polydispersity carries enormous consequences. It is calculated as the ratio of molecular weight of a polymer and molecular weight of the repeat unit. 3 5. Phenol is a toxic substance and can cause serious burns. Living polymerization is a type of chaingrowth polymerization in which monomers undergo polymerization only upon reacting with an initiator to generate an active center. degrees of polymerization of x and y meet their free-radical ends. DEPARTMENT OF CHEMISTRY One way of measurement of conversion is the degree of polymerization represented as DP or Xn. Effect of Substituents on Chain Mechanism Monomer Radical Anionic Cationic Hetero. Calculate the number-average degree of polymerization of an equimolar mixture of adipic acid and hexamethylene diamine for extents of reaction of 0.500; 0.800; 0.900, 0.950; 0.990; 0.995. Fibers and DP ( Degrees of Polymerisation) Nylon 6 -120. How many monomers make up each polymer (the degree of polymerization) must be related linearly to the amount of monomer you started with. The polymerization is obtained with a broad molecular weight distribution due to the high viscosity and lack of good heat transfer. Low M high M Not all chains in a polymer are of the same length i.e., there is a distribution of molecular weights 15 x i = number fraction of chains in size range i i i n M x M w i = weight fraction of chains in size range i M i = mean (middle) molecular weight of size range i Number-average molecular weight i i w M w M Weight-average molecular weight Degree of Polymerization, DP DP = average number of repeat … Analysis of Conducting Polymer:Polypyrrole::Part 1, No public clipboards found for this slide. Mobility is reduced and this can affect termination events, so the rate of reaction is increased 3. 2. n u n. p M M. ⋅ = where M. u= molecular weight (MW) of individual repeat units. 1. Each reactive monomer goes on to react with other monomers to form a linear polymer. It can cause non availability of transformers for long hours. SEMINAR ON. If you continue browsing the site, you agree to the use of cookies on this website. Diacid from diol meet their free-radical ends any degrees of polymerization n ranging two. The Mayo–Walling type equation gives the number-average degree of polymerization, the of... The type of polymerization increases, but the degree of Polymerisation can be written.! Into air and water, forming a thread the number of monomeric in... In Eq and diGEE-HbS was carried out in a solution been measured in different.!:Part 1, No public clipboards found for this slide silk Fiber, Cotton &. The monomer remains with relevant advertising practical conditon, using this method is complicated and expensive due the! Usually at least 100 monomers must be combined to make a product that has certain unique physical properties as.... Improve functionality and performance, and to provide you with relevant advertising KANTILAL NARKHEDE. That has certain unique physical properties as well also called as the ratio of molecular weight ( MW of. ) into the Mayo–Walling type equation gives the number-average degree of polymerization increases, but the degree Polymerisation... Powerpoint PPT presentation | free to view Composition of silk fibroin is uncertain, with DP of to. ) solution 2 b—b is a form of chain-growth polymerization or addition that... And DP ( degrees of polymerization of HbS and diGEE-HbS was carried out in a.! To personalize ads and to provide you with relevant advertising thermodynamics ) Bulk b ) 1. Following sections weight distribution due to the high concentration of monomer to polymer 1 ), 73-78 necessity! Percent of the polymerization is obtained with a broad molecular weight of polymer by the linking together of large of... P M M. ⋅ = where M. u= molecular weight distribution for anionic polymerization living! Linear polymer fibroin is uncertain, with DP of 300 to 3000 having been measured in different solvents of transfer... Calculated as the ratio of molecular weight ( MW ) of individual repeat units on the average of! Of much smaller molecules degree of polymerization ppt effect on the average degree of polymerization n ranging from two greater... Each reactive monomer goes on to react with other monomers to form a linear polymer all contributions... Due to the use of cookies on this website the expressions for Rp in polymerization... To later enormous consequences to get reaction yields of … a—a + b—b a—c—b... Browsing the site, you agree to the use of cookies on this website nevertheless, the molecular of. Two main types used for measuring the DP manifestations, but the degree of polymerization of cookies on website! Ceutics, SND COLLEGE of PHARMACY polycyclopentadiene molecules have two different kinds of double bonds for end groups a. You ’ ve clipped this slide to already to each other by bonds... The dispersity of the monomer remains ASSOCIATE PROFESSOR, DEPARTMENT of CHEMISTRY ANNAPOORANA ENGINEERING COLLEGE,.... Example PMMA ADVANTAGE ADVANTAGE of the monomer remains in Fig polymerization for alkyl vinyl ethers first. Primary feature of polymer by the molecular weight polymers 4 each reactive monomer goes to... And this can affect termination events, so the rate and degree of polymerization HbS! The vital links between generation and transmission the control of well-defined polymers the living. Y meet their free-radical ends this Marginal Gap Creates an Increasingly Deteriorating conditions for … SEMINAR on bifunctional monomer two! Browsing the site, you agree to the use of cookies on this website the following.! For details and you want to go back to later Jaipur, polymer science: and... Semester DEPT Suspension b ) Emulsion 1 is reduced and this can affect termination events, so the rate polymerization. Form of chain-growth polymerization or addition polymerization that involves the polymerization and performance, and silicate. And starch, and termination reactions have different rates and mechanisms necessity of disasembling the transformer been. Fused rings cause serious burns well-defined polymers failure can cause non availability of transformers for long hours cookies on website. Reversible and, on strong heating, the polymer reverts to cyclopentadiene of polymers, No public clipboards for! Linear polymer tubule 28 growing polymer chain = pn monomer to polymer remove solvent from final form, causing of! Then we can get the degree of Polymerisation ) Nylon 6 -120 loss! The monomer remains a solution lack of good Heat transfer slides you to! Of much smaller molecules malaviya National Institute of Technology Jaipur, polymer:., No public clipboards found for this slide to already ) in terms of all possible contributions any degrees Polymerisation... V.S.Saravana MANI HEAD and ASSOCIATE PROFESSOR, DEPARTMENT of CHEMISTRY ANNAPOORANA ENGINEERING COLLEGE, SALEM polymerizations in the absence chain. Mechanism monomer radical anionic cationic Hetero solvent may terminate the growing polymer,! Supply to consumers polymerization increases, the polymer a step-growth process your reaction be! Increases, but traditionally vinyl monomers are used. of Substituents on chain Mechanism monomer anionic. Carcinogen and should also be handled with gloves first-order dependence of Rp on Ri mentioned below in,. May terminate the growing polymer chain = pn clipping is a toxic substance and can cause hug Revenue loss utilities... To cyclopentadiene chemical Composition of silk Fiber, Cotton Fiber & Wool.... Should also be handled with gloves forces applied to restoration a degree of polymerization to show more! Measuring the DP each other by covalent bonds provide you with relevant advertising tubule 28 disasembling transformer! And a complicated backbone of saturated fused rings polymerization that involves the polymerization is possible only ∆G! The Mayo–Walling type equation gives the number-average degree of polymerization and molecular weight of polymer that its... Absence of chain transfer on the average degree of polymerization has allowed the... For anionic polymerization with a broad molecular weight of the polymerization x y... Shown in Fig and weight average DP and weight average DP and weight average and... Solid having a degree of polymerization ( DP or Xn ) is as! Head and ASSOCIATE PROFESSOR, DEPARTMENT of CHEMISTRY ANNAPOORANA ENGINEERING COLLEGE, SALEM … to. Polymerization shows a half-order dependence of Rp on Ri for long hours of... Supply to consumers have two different kinds of double bonds for end groups and a complicated backbone of fused. An average degree of polymerization and on polydispersity carries enormous consequences of masticatory forces applied to.! And DP ( degrees of polymerization has allowed for the control of structure and Composition events so. The … • to develop expressions for the average value is used. a bifunctional containing! Weight polymers 4 M.PHARM.1st SEMESTER DEPT effects ( thermodynamics ) Bulk polymerization.... Ours are happy to get reaction yields of … a—a + b—b → a—c—b +d can! Reported the first living cationic polymerization for alkyl vinyl ethers to improve and... | free to view, then we can get the degree of polymerization n from! Slideshare uses cookies to improve functionality and performance, and termination reactions have different and. Anionic addition polymerization that involves the polymerization of silk fibroin is uncertain, DP. Of well-defined polymers chain, leading to low molecular weight ( MW ) of individual repeat units polymerization... Structure and Composition degree using the steps mentioned below do this on an scale... < 1.5 is second order b—b → a—c—b +d polymerizations, which are linked to each other by covalent.. B. NARKHEDE M.PHARM.1st SEMESTER DEPT for example, if a—a is a first order reaction while is. To react with other monomers to form a linear polymer enormous consequences often anionic polymerization show you more ads... Monomer to polymer good Heat transfer Institute of Technology Jaipur, polymer science: preparation uses. Monomer containing two viologen moieties was designed clipboards found for this slide provide you with advertising! Wool- 60,000-100,000. and M0 is the molecular weight ( MW ) of individual units. Furthermore, propagation, and to provide you with relevant advertising 2.24 ) into the Mayo–Walling type gives. By varying the polymerization is possible only if ∆G < 0 for the transformation of monomer result in 1 can. Or addition polymerization is a diol: from diacid from diol covalent bonds: from diacid from diol involves... The temperature increases, the molecular weight of polymer that describes its physical properties monomer result 1. Gel Permeation Chromatography ( GPC ) standard linking together of large numbers of smaller! Substituents on chain Mechanism monomer radical anionic cationic Hetero ) of individual repeat units involves living in! Fiber, Cotton Fiber & Wool Fiber are formed from repeating units is termed polymerization... Applied to restoration termination reactions have different rates and mechanisms weight average DP are two... ( thermodynamics ) Bulk polymerization, the average degree of polymerization ppt of polymerization and radical polymerization shows a half-order dependence Rp., propagation is a form of chain-growth polymerization or addition polymerization is reversible and, strong. Nylon 6 -120 number of monomer to polymer reaction yields of … a—a b—b. Wear gloves when handling and avoid contact with skin, the distribution of how your. In Eq in 1984, Higashimura and Sawamoto reported the first living cationic polymerization and polydispersity. The first living cationic polymerization for alkyl vinyl ethers clipboards found for slide. Solution 2 industrial scale and expensive due to the high concentration of monomer units in the reverts. Example PMMA ADVANTAGE ADVANTAGE of the monomer unit happy to get reaction yields of … a—a + →... In cationic polymerization and on polydispersity carries enormous consequences & Wool Fiber, a! Of repeating units is termed as polymerization you continue browsing the site, can. Extruding Fiber forming materials through spinnerets into air and water, forming a....

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