Atrp has been thoroughly investigated since it was developed independently by matyjaszewski and wang12 and sawamoto et al. If the monomers add end to end and liberate a byproduct is called step growth polymerization. Here molecular weight of monomer and repeat unit is different, bi product my h 2 o, co 2, nh 3 etc. The oldest polymers rejuvenated leen billiet, david fournier, filip du prez volume 50, issue 16, 31 july 2009, pages 38773886.
Current experimental understanding and modeling progresses on particle fragmentation. Check our section of free ebooks and guides on polymer chemistry now. Freeradical polymerization frp is a method of polymerization by which a polymer forms by the successive addition of freeradical building blocks. Pdf reinvestigation of numerous ringopening polymerizations by means of. 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.
During propagation, only monomers react to the active site at the end of the growing chain. There are many forms of polymerization and different systems exist to categorize them. Simultaneous chaingrowth and stepgrowth polymerizationa new route to. Readings synthesis of polymers chemical engineering. Transitionmetalfree controlled polymerization of 2. The predicted behaviour of growing polyethylene was explained by. Differences between step growth polymerization and chain growth polymerization. New polymerization techniques and synthetic methodologies electronic resource publication date 2001 topics polymerization, gums and resins, synthetic. Free radical polymerization is the most widely used process for polymer synthesis. Reversible additionfragmentation chain transfer polymerization. Step growth polymerization, types of monomers, kinetics and equilibrium considerations, closed vs. Polymerization is a process of reacting monomer molecules together in a chemical reaction to form linear chains or a threedimensional network of polymer chains 1. In general, two classes of stepgrowth polymerization sgp reactions.
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. Step polymerisation free download as powerpoint presentation. Well over 100 billion pounds of polymer are produced each year, and it is expected that this. Stepgrowth polymerization process modeling and product. Anyone can learn for free on openlearn, but signingup will give you access to your personal learning profile and record of achievements that you earn while you study. Number distribution and number average molecular weight mn. This page contains list of freely available ebooks, online textbooks and tutorials in polymer chemistry. Polymer synthesis a s discussed in chapter 1, a useful classification of all polymers is based upon the kinetics of the polymerization. We use cookies to offer you a better experience, personalize content, tailor advertising, provide social media features, and better understand the use of our services. Two types of monomers can undergo step growth polymerizations. Review the full course description and key learning outcomes and create an account and. Polymer size distribution filament size distribution it is very common in mathbiology to consider size classes and formulate equations for the dynamics of size.
Chapter two, stepgrowth polymerization, version of 1505 76 2. Following its generation, the initiating free radical adds nonradical monomer units, thereby growing the polymer chain. Coordination polymerization contains the proceedings of a symposium sponsored by the american chemical society and held at the university of californialos angeles on april 3, 1974. Synthesis by ringopening metathesis polymerization, film morphology, and resonant luminescence from microspheres. New polymerization techniques and synthetic methodologies electronic resource.
Chapter two, step growth polymerization, version of 1505 76 2. Polymers products that are commonly referred to as plastics by the general public are known to chemists as polymers. Quantitative analysis of stepgrowth polymers by size exclusion chromatography. Reaction engineering of step growth polymerization. Stepgrowth polymerization forms polymers in a manner that is quite different from chain growth polymerization. Stepgrowth polymerization request pdf researchgate. Particle growth during the polymerization of olefins on supported catalysts. View principles of polymerization 4th edition by odian solution manual from chem 101 at inha university. Thus at 75 per cent completion, the average degree of polymerization is one quarter of that. Bulk polymerization or mass polymerization is carried out by adding a soluble radical initiator to pure monomer in liquid state. Step growth polymerization process modeling and product design. The electrophilic aromatic substitution reactions of ketones.
First, we examine how the degree of polymerization. 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. This is an enlargement of this plot in the region 95% conversion. Chain growth polymerization an overview sciencedirect. These polymerization techniques generate many important commodity polymers where their broad range of molecular weight distribution gives rise to important physical properties. 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. This assumption greatly simplifies the otherwise very complicated kinetics of a condensation polymerization. Lecture 7 step growth polymerization polymer synthesis. The nstep trajectory of the random walker is a chain of length nb folded. In this classification scheme, a step growth polymerization is defined as one that involves a random reaction of two molecules that may be any combination of a monomer, oligomer, or a longerchain molecule.
Many naturally occurring and some synthetic polymers are produced by stepgrowth polymerization, e. A detailed discussion of several important step growth polymeriz ations follows in the next five chapters. Types of polymerization chain growth polymerization free radical ionic cationic anionic insertion ring opening polymerization step growth polymerization. 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. Novel, linear, highmolecularweight singlestrand heteroaromatic polymers and copolymers containing 9hxanthene moieties in the backbone were synthesized by metal free superacidcatalyzed stoichiometric and nonstoichiometric step growth polymerizations of carbonyl compounds bearing electronwithdrawing substituents with bisphenols. Chaingrowth polymerization, by contrast, requires at least three distinctly different kinds of reactions to describe the mechanism. Chemical engineering, faculty of engineering, semarang state universitybldg. This is known as step growth and is shown in figure 36 b. Free polymer chemistry books download ebooks online.
These are quite general, and can easily be applied in such diverse and emerging fields as polymerization applications in photolithography and microelec tronics. 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. Molecule empire building by radical groups chaingrowth polymerization addition processes 1. An example is adipic acid that has two functional groups. Atom transfer radical polymerization atrp one of the most widely studied controlled radical polymerization techniques is atom transfer radical polymerization atrp. Reaction engineering of step growth polymerization springerlink. 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. Differences between stepgrowth polymerization and chaingrowth polymerization step growth chain growth growth throughout matrix rapid loss of. Polymer design and synthesis, reaction types and processes, introduction to step growth polymerization, types of monomers. Chemical engineering 160260 polymer science and engineering. Free radicals can be formed by a number of different mechanisms, usually involving separate initiator molecules. Predicting chain length distribution in step growth.
What is the difference between stepgrowth polymerisation, chaingrowth polymerisation and copolymerisation. Controlled radical polymerization guide sigmaaldrich. Polymer synthesis i am inclined to think that the development of polymerization is. Since all the monomer molecules can interact with one another, the length of the chains increases more slowly during the course of polymerization. In this classification scheme, a stepgrowth polymerization is defined as one that involves a random reaction of two molecules that may be any combination of a monomer, oligomer, or a longerchain molecule. Monomer molecules and freeradical initiators are added to a waterbased. In stepgrowth polymerizations, any species monomers, dimers, trimers, etc.
Lightinduced stepgrowth polymerization of abtype photo. Free radical in slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. The distinction between step growth polymerization and chain growth polymerization was introduced by paul flory in 1953, and refers to the reaction mechanisms, respectively. Read here for free the full introductory essay by andrew dove and michael meier. Introduction to polymers quiz 7 090225 this week we discussed chain growth polymerization using free radical initiators.
The supporting information is available free of charge on the acs. Pdf particle growth during the polymerization of olefins on. Made by faculty at the university of colorado boulder department of chemical and biological engineering. The process of formation of polymer by repeaeted condensation reaction between two bi functional monmers is called step growth polymerization or condensation.
Chemical engineering, faculty of engineering, gadjah mada university jl. In step growth polymerizations, any species monomers, dimers, trimers, etc. View notes lecture 7 step growth polymerization from bme 510. This can induce chain branching through the terminal double bond propagation reaction. The kinetics of the stepgrowth polymerization can be described with florys equal reactivity principle. Nylon is commonly made by stepgrowth polymerization. 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. Made by faculty at the university of colorado boulder department of chemical and biological. All molecules present monomer, oligomer, polymer can react with any other molecule. Step growth polymerization is an important process for producing polymer materials, such as epoxy, silicone, nylon, kevlar, polycarbonates, polyurea, polyanhidride, polyester, polyamides. Free radical polymerization frp is a method of polymerization by which a polymer forms by the successive addition of free radical building blocks. Step growth polymerization process modeling and product design seavey, kevin, liu, y.
Both are polyfunctional, but one type possess only one kind of functionality. Step polymerisation polymerization materials science. Growth polymerization process modeling and product. Jan 30, 2012 an introduction to step growth polymerization. Principles of polymerization 4th edition by odian solution. A polymer is a macromolecule which consists of small molecular units that are repeated over and over again to form a long chain. Welldefined functional starshaped polymer structures with up to 29 arms have been successfully synthesized by the combination of atom transfer radical. Srivatsan and others published step growth polymerization, process modeling and product design find, read and cite all the research you need on researchgate. The first six chapters present the principles of step growth polymerization. Chemical engineering 160260 polymer science and engineering lecture 3 molecular weight.
New polymerization techniques and synthetic methodologies. 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 deploy. The reaction is initiated by heating or exposing to radiation. Monomer syntheses, polymerization procedures, and additional experimental data pdf.
Predicting chain length distribution in step growth polymerization by monte carlo method wahyudi budi sediawan1, megawati2. Comprehensive heterocyclic chemistry iii, 2008 related terms. Free radical polymerization is particularly suitable for polymerizing monomers containing carboncarbon double bonds. Step growth polymerization, process modeling and product. Transformation of stepgrowth polymerization into living. Note how low the degree of polymerization, and thus the molecular weight of a polymer is before the reaction reaches conversions 98%. Comparison of common polymerization methods stepgrowth chaingrowth anionic growth method cons. Free polymerization velocity monomer size load force thermal energy v v v v v. While the demands on materials continue to expand, stepgrowth polymerization reactions will remain relevant and useful to researchers across the research sectors. Files available from the acs website may be downloaded for. The molecular weight mw of plla is a significant determinant of the quality of its products and can be tailored while synthesizing it through step growth polymerization of lactic acid or chain growth polymerization of lactide dimer, both in bulk as well as in solution state 3.
New polymers synthesis by organocatalyzed stepgrowth. Stepgrowth polymerization article about stepgrowth. We performed two synthesizes for polystyrene involving bulk polymerization and emulsion polymerization. The two most important stepgrowth polymerizations are condensation and addition polymerization. This is one of the earliest topics i was teaching in the polymer science and engineering course. Nov 10, 2015 transformation of stepgrowth polymerization into living chaingrowth polymerization. Step growth polymerization free online course materials. Differences between step growth polymerization and chain growth polymerization step growth chain growth growth throughout matrix rapid loss of monomer early in the reaction similar steps repeated throughout reaction process average molecular weight increases slowly at low conversion and high extents of reaction are. Step growth polymerization mit opencourseware free. What is the difference between stepgrowth polymerisation. 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. As the reaction proceeds the mixture becomes more viscous. Yenjen lin, hsinyu chiang, osamu oki, soh kushida, shuwei chang, shihting chiu, yohei yamamoto, takuya hosokai, masaki horie.
Stepgrowth polymerization process modeling and product design seavey, kevin, liu, y. Flory assumed that all steps, that is, the formation of dimers, trimers and so forth, have equal rate constants. Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation. Synthesis of polythene refer above ii step growth polymerization. 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. Find materials for this course in the pages linked along the left. 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 refers to a type of polymerization mechanism in which bifunctional. Chain growth polymerization has been successfully performed for many decades through conventional free radical, anionic, or cationic polymerization. Principles of polymerization 4th edition by odian solution manual. Other articles where stepgrowth polymerization is discussed. Pdf simultaneous chaingrowth and stepgrowth polymerization. Chaingrowth polymerization has been successfully performed for many decades through conventional free radical, anionic, or cationic polymerization. In general, two classes of step growth polymerization sgp reactions are considered.
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