The monomer in stepgrowth polymerization will be consumed very quickly to dimer, trimer or oligomer. In stepgrowth polymerizations, any species monomers, dimers, trimers, etc. Figure 41 molecular mass distributions in step growth polymerization. The mechanism requires that at least two different monomers participate. Our pdf merger allows you to quickly combine multiple pdf files into one single pdf document, in just a few clicks. Step growth polymerization, types of monomers, kinetics and equilibrium considerations, closed vs. The first six chapters present the principles of step growth polymerization.
Comparison of common polymerization methods stepgrowth chaingrowth anionic growth method cons. Chemical engineering 160260 polymer science and engineering. These are quite general, and can easily be applied in such diverse and emerging fields as polymerization applications in photolithography and microelec tronics. Stepgrowth polymerization refers to a type of polymerization mechanism in which bifunctional or multifunctional monomers react to form first dimers, then trimers, longer oligomers and eventually long chain polymers. These unsaturated monomers the identical molecules that make up the polymers have extra internal bonds that are able to break and link up with other monomers to form a repeating chain, whose backbone typically contains. Two other types of monomers that combine via stepgrowth polymerization. Atom transfer radical polymerization atrp has proven to be a powerful technique to obtain polymers with narrow polydispersities and controlled molecular weight. The reactivity of a functional group is independent of the size of the molecule to which it is attached.
The other process, called step growth polymerization, involves the buildup of molecular weight not in a chainlike fashion but in a stepwise fashion, by the random combination of monomer molecules containing reactive functional groups. Stepgrowth polymerization refers to a type of polymerization mechanism in which bifunctional or multifunctional monomers react to form first dimers, then. Chapter two, stepgrowth polymerization, version of 1505 76 2. Stiile colorado state university, fort collins, co 80523 as illustrated in the articles on chain polymerization, a chaingrowth polymerization is one in which each polymer chain, after being started by a free radical initiator, a cationic catalyst or an anionic catalyst, grows rapidly, producing a high. Many naturally occurring and some synthetic polymers are produced by stepgrowth polymerization, e. Feature article stepgrowth polymerization and click chemistry. In general, two classes of step growth polymerization sgp reactions are considered. Strategic process modeling facilitates accurate prediction of the properties. Compared to chaingrowth polymerization, where the production of the growing chaingrowth is based on the reaction between polymer with active center and monomer, stepgrowth polymerization doesnt have initiator or termination. Step polymerisation polymerization materials science. Why pdi is usually greater than 2 in real polymerization system.
Durham etheses some studies in stepgrowth photoreductive. The oldest polymers rejuvenated leen billieta, david fournierb, filip du preza, adepartment of organic chemistry, polymer chemistry research group, ghent university, krijgslaan 281 s4bis, b9000 ghent, belgium. Initiation, propagation, termination, and chain transfer molar mass of backbone chain increases rapidly at early stage. Stepgrowth polymerization american chemical society. It is known that chaingrowth polymerization can create a more heterogeneous network structure than stepgrowth polymerization. The number distribution a is shown for three different extents of reaction, the mass distribution b shows a single narrow peak which progressively broadens and shifts to high molecular mass as. Growth regulated by regulating nucleation of new barbed ends this is done by regulating the amount of active arp23. Growth polymerization process modeling and product. Why pdi is usually greater than 2 in real polymerization. Long and others published stepgrowth polymerization find, read and cite all the research you need on researchgate. Usually, for chain growth polymerization, there is no byproduct formed. Putting them together polymer science learning center.
Just think of the way your bank keeps merging with other banks and getting. Stepgrowth polymerization article about stepgrowth. Bivariate distribution and related analytical solutions for batch. Jan 30, 2012 an introduction to step growth polymerization. Merging macromolecular and supramolecular chemistry into. Chain growth polymerization involves the linking together of molecules incorporating double or triple carboncarbon bonds. Growth proceeds by a step wise intermolecular reaction growth involves monomer units reacting with each other or with oligomers of any size the reactivity of a functional group is independent of the size of the molecule to which it is attached the reactivity of a functional group is independent of. Stepgrowth polymerization an overview sciencedirect. How to combine files into a pdf adobe acrobat dc tutorials. This is a stepgrowth polymerization not a chaintransfer or radical polymerization. In step growth polymerizations, any species monomers, dimers, trimers, etc. Now the differences between a chain growth polymerization and a step growth. Step growth polymerization of inorganic nanoparticles article pdf available in science 3295988.
Apr 30, 2015 characteristics of chain growth polymerisation growth by addition of monomer only at one end or both ends of chain some monomer remains even at long reaction times different steps operate at different stages of mechanism i. Flory assumed that all steps, that is, the formation of dimers, trimers and so forth, have equal rate constants. Made by faculty at the university of colorado boulder department of chemical and biological engineering. Following a comparison of chain growth and step growth polymerization, focuses on the latter process by describing requirements for high molecular weight, step growth polymerization kinetics, synthesis and molecular weight distribution of some linear step growth polymers, and threedimensional network step growth polymers. Chaingrowth polymerization, by contrast, requires at least three distinctly different kinds of reactions to describe the mechanism. Owing to the many advantages over step growth polymerizations, chain growth polymerization has been utilized in a variety of controlled polymer synthesis, including many important industrial. Other articles where step growth polymerization is discussed. Stiile colorado state university, fort collins, co 80523 as illustrated in the articles on chain polymerization, a chain growth polymerization is one in which each polymer chain, after being started by a free radical initiator, a cationic catalyst or an anionic catalyst, grows rapidly, producing a high molecular weight polymer. Step growth polymerization is the method most commonly employed, although hydrogenbonddriven polypseudorotaxane formation has also been reported from preformed polyurethane backbones in combination with 30crown10 or 42crown14 rings. Chapter three, chaingrowth polymerization, version of. In fact polyurethane polymerizes with addition polymerization because its polymerization produces no small molecules, but its reaction mechanism corresponds to a step growth polymerization.
Predicting chain length distribution in step growth. Understand quantitative model step growth polymerization plans and how to predict properties of the product polymer with the essential information in step growth polymerization process modeling and product design. Here molecular weight of monomer and repeat unit is different, bi product my h 2 o, co 2, nh 3 etc. Reaction engineering of step growth polymerization springerlink. Copy of 0510 quiz 3 introduction to polymers this week we saw a demonstration of nylon synthesis, we generally discussed stepgrowth or condensation and chaingrowth or addition polymerization and went through a list of about 30 common polymers and copolymers including their chemical structure. Choose from a variety of file types multiple pdf files, microsoft word documents, microsoft excel spreadsheets, microsoft powerpoint. Predicting chain length distribution in step growth polymerization by monte carlo method wahyudi budi sediawan1, megawati2.
Ppg industries has received a patent for a compound that is comprised of the reaction product of a highly branched polymer having terminal amine functional groups and a lactam, wherein the highly branched polymer is the step growth polymerization reaction product of a polyfunctional first monomer having a first functional group and a polyfunctional second monomer having a second functional. The kinetics of the stepgrowth polymerization can be described with florys equal reactivity principle. A single difunctional monomer difunctional monomers may react to form polymer chains. At that time we noted that these classifications could be based on the following. A detailed discussion of several important step growth polymeriz ations follows in the next five chapters. The easiest way to visualize the stepgrowth mechanism is a crowd of people reaching out. The functional groups on two monomers react to form a dimer, the dimer reacts with another monomer to form a trimer, and these reactions lead to many monomeric units linked to form an intermediate molecular weight material, which is known as an oligomer, and eventually a polymer. Stiile colorado state university, fort collins, co 80523 as illustrated in the articles on chain polymerization, a chaingrowth polymerization is one in which each polymer chain, after being started by a free radical initiator, a cationic catalyst or an anionic catalyst, grows rapidly, producing a high molecular weight polymer. If the monomers add end to end and liberate a byproduct is called step growth polymerization. Reaction engineering of step growth polymerization.
The number distribution a is shown for three different extents of reaction. In the following example, the same bisphenol a intermediate used as a monomer for lexan serves as a. If you want to learn how to simulate stepgrowth polymerization processes using commercial software and seek an indepth, quantitative understanding of how to develop, use, and. Comprehensive heterocyclic chemistry iii, 2008 related terms. Step growth polymerization p olymerization mechanism in which bifunctional or multifunctional monomers react to form first dimers, then trimers, longer oligomers and eventually long chain polymers. Stepgrowth polymerization an overview sciencedirect topics. This free online tool allows to combine multiple pdf or image files into a single pdf document. The technique is the most studied and utilized of the controlledliving radical polymerization techniques since a large number of monomers. To see an animated model of the radical chaingrowth polymerization of vinyl chloride. As the name suggests, step growth polymerization proceeds in a step wise fashion. Dec 04, 2014 the traditional polycondensation for polyesters and polyamides but also, more recently, click reactions, olefin metathesis, multicomponent reactions, and many others have been used for stepgrowth polymerization allowing a finetuning of chemical structure and thus also of the properties of the obtained materials.
Polymer synthesis a s discussed in chapter 1, a useful classification of all polymers is based upon the kinetics of the polymerization. In general, two classes of stepgrowth polymerization sgp reactions. In contrast, chaingrowth polymerization occurs by introducing an active growth center into a monomer, followed by the addition of many monomers to that center by a chaintype kinetic mechanism. All molecules present monomer, oligomer, polymer can react with any other molecule. The other process, called stepgrowth polymerization, involves the buildup of molecular weight not in a chainlike fashion but in a stepwise fashion, by the random combination of monomer molecules containing reactive functional groups. Other articles where stepgrowth polymerization is discussed. When two or more reactive functional group reacts with each other is called condensation type polymerization. Chapter two, stepgrowth polymerization, version of 1505 75 2 stepgrowth polymerization 2. Stepgrowth polymerization is also used for preparing a class of adhesives and amorphous solids called epoxy resins. Following a comparison of chaingrowth and stepgrowth polymerization, focuses on the latter process by describing requirements for high molecular weight, stepgrowth polymerization kinetics, synthesis and molecular weight distribution of some linear stepgrowth polymers, and threedimensional network stepgrowth polymers.
Combines pdf files, views them in a browser and downloads. Chapter two, step growth polymerization, version of 1505 75 2 step growth polymerization 2. In this equation, p is the polymer while x represents degree of polymerization, means active center of chain growth polymerization, m is the monomer which will react with active center, l is a lowmolarmass byproduct obtained during chain propagation. During propagation, only monomers react to the active site at the end of the growing chain. Many naturally and synthetic polymers are produced by stepgrowth. Ppg industries has received a patent for a compound that is comprised of the reaction product of a highly branched polymer having terminal amine functional groups and a lactam, wherein the highly branched polymer is the stepgrowth polymerization reaction product of a polyfunctional first monomer having a first functional group and a polyfunctional second monomer having a second functional. Effects of the polyethylene glycol hydrogel crosslinking. If you want to learn how to simulate step growth polymerization processes using commercial software and seek an indepth, quantitative understanding of how to develop, use, and deploy. Chemical engineering, faculty of engineering, semarang state universitybldg. Open systems kinetics of step growth polymerization chapter 2. Citescore values are based on citation counts in a given year e. This assumption greatly simplifies the otherwise very complicated kinetics of a condensation polymerization. Growth proceeds by a stepwise intermolecular reaction. Stepgrowth polymerization process modeling and product.
This assumption greatly simplifies the otherwise very complicated kinetics of a. Step growth polymerization and condensation polymerization are two different concepts, not always identical. Synthesis of star polymer with linear polytriazole arms from a core. Pdf stepgrowth polymerization of inorganic nanoparticles.
Step growth polymerization and condensation polymerization step growth polymerization and condensation polymerization are two different concepts, not always identical. Stepgrowth polymerization is the method most commonly employed, although hydrogenbonddriven polypseudorotaxane formation has also been reported from preformed polyurethane backbones in combination with 30crown10 or 42crown14 rings. In chain growth or chain polymerization, the only chainextension reaction step is the addition of a monomer to a growing chain with an active center such as a free radical or ion. Chaingrowth polymerization or chain polymerization is a polymerization technique where. Understand quantitative model stepgrowth polymerization plans and how to predict properties of the product polymer with the essential information in stepgrowth polymerization process modeling and product design. Once the growth of a chain is initiated by formation of an active center, chain propagation is usually rapid by addition of a sequence of monomers. Stepgrowth polymerization forms polymers in a manner that is quite different from chain. Transformation of stepgrowth polymerization into living. The mass distribution b shows a single narrow peak which progressively broadens and shifts to high molecular mass as. Nanoparticles from stepgrowth coordination polymerization. Transformation of stepgrowth polymerization into living chain. Growth involves monomer units reacting with each other or with oligomers of any size.