What is polymerization: Definition and 22 Discussions

In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many forms of polymerization and different systems exist to categorize them.
In chemical compounds, polymerization can occur via a variety of reaction mechanisms that vary in complexity due to the functional groups present in the reactants and their inherent steric effects. In more straightforward polymerizations, alkenes form polymers through relatively simple radical reactions; in contrast, reactions involving substitution at a carbonyl group require more complex synthesis due to the way in which reactants polymerize. Alkanes can also be polymerized, but only with the help of strong acids.As alkenes can polymerize in somewhat straightforward radical reactions, they form useful compounds such as polyethylene and polyvinyl chloride (PVC), which are produced in high tonnages each year due to their usefulness in manufacturing processes of commercial products, such as piping, insulation and packaging. In general, polymers such as PVC are referred to as "homopolymers", as they consist of repeated long chains or structures of the same monomer unit, whereas polymers that consist of more than one monomer unit are referred to as copolymers (or co-polymers).
Other monomer units, such as formaldehyde hydrates or simple aldehydes, are able to polymerize themselves at quite low temperatures (ca. −80 °C) to form trimers; molecules consisting of 3 monomer units, which can cyclize to form ring cyclic structures, or undergo further reactions to form tetramers, or 4 monomer-unit compounds. Such small polymers are referred to as oligomers. Generally, because formaldehyde is an exceptionally reactive electrophile it allows nucleophilic addition of hemiacetal intermediates, which are in general short-lived and relatively unstable "mid-stage" compounds that react with other non-polar molecules present to form more stable polymeric compounds.
Polymerization that is not sufficiently moderated and proceeds at a fast rate can be very hazardous. This phenomenon is known as autoacceleration, and can cause fires and explosions.

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  1. bo reddude

    Exploring the Math of Glucose Polymers: Understanding 6^n

    Let's say you have n glucose monomers. (C6H12O6) n You want to find out how many possible polymers exist in combining those n number of glucose molecules randomly. So glucose_1 has 6 OHs that can combine with glucose_2 which also has 6 OHs. Starting with glucose_1's first carbon C1, at that...
  2. P

    Medical Biochemistry (Nucleotide Polymerization)

    Hi everyone! I did some multiple choice tasks and got stuck on two statements: "In RNA, the sugar is present in the 2'-endo conformation". This statement is false, but why? What conformation does the sugar molecule have? How do I recognize the conformation? "When two nucleotides polymerize...
  3. G

    Polymer Physics: molar mass, polymerization

    Homework Statement Consider a “true macromolecule” - a chunk of polybutadiene network of mass 100g. How many monomers all covalently bonded together does it contain if the molar mass of the monomer is Mmon= 54g/mol? What is the molar mass of this macromolecule? Homework Equations Molar mass...
  4. S

    Experiments with interfacial polymerization

    I'm wanted to do an experiment with interfacial polymerization; producing nylon 6,10 with sebacoyl chloride and hexanediamine. I was wondering what aspects of this reaction I could research, or what variables I can change?
  5. S

    What are some good polymerization chemistry experiment ideas

    I'm very interested in researching polymerization chemistry for my school science fair. All the ideas I have are either too expensive or not complex enough.
  6. C

    Atom-Transfer Radical Polymerization: Method Question

    Hi everyone, So I'm a chemical engineering grad student and oddly enough I have been tasked with doing chemistry (strange I know). I'm currently doing atom-transfer radical polymerization (ATRP) using a metal (CuCl or CuBr) and a ligand (dNbpy or PDMETA). My monomer is a methacrylate group...
  7. T

    What are the essential conditions for polymerization to take place?

    Homework Statement What three conditions or ingredients are necessary for polymerization to occur? The Attempt at a Solution I know that carbon is necessary because it is the only element that can form complex molecules readily in nature. But when i try to research this problem it seems there...
  8. S

    Polymerization of acrylamide with K Persulfate without Bis

    Hi! I recently did a lab where my group was to create a polymer via free-radical polymerization. We used acrylamide and potassium persulfate. We DID NOT use bis acrylamide crosslinker ( wasnt in our lab manual for some reason.) I cannot find any web resources that show how acrylamide...
  9. D

    Reaction energy for polymerization of polychloroprene

    Homework Statement Please see attached for problem statement and table of bond energies. My chemistry background is awful and this is from a materials science textbook. The question is, how would I approach/solve 2.31 (only parts b and c).Homework Equations The Attempt at a Solution We go from...
  10. J

    Free radical polymerization

    Does branching occur during free radical polymerization of ethylene even at high temperatures and pressure or only on other type of monomers using free radical polymerization at lower temperatures? I was reading this article: http://en.wikipedia.org/wiki/Polymerization It was not very...
  11. Weissritter

    Aftermath of polymerization of EtOH

    In a very similar way to my first post ever, a short series of reactions came to mind that could be seen as apparent magic. You could use it for gaining instantaneous fame in a party, convincing people into pay attention to chemistry in basic levels of education and in conjunction with a time...
  12. U

    Enthalpy of Polymerization Calculation for Ethylene

    Homework Statement The polymerization of ethylene to linear polyethylene is represented by the following reaction nCH_{2}=CH_{2} \rightarrow (-CH_{2}-CH_{2}-)_{n} where n=large integer value Calculate the enthalpy of polymerization per mol of ethylene at 298K if average bond enthalpies of bond...
  13. V

    TPR solvent AND home-made UV polymerization

    TPR: I need to find or create a solvent based glue for TPR. Is there something I can purchase that will chemically bond TPR to itself? The application is a simple TPR molded sample we got from china, we had to cut it open to get to the electronics and now we need to glue it back together...
  14. A

    Organic Chemistry - Polymerization of Propene to Polypropylene

    Homework Statement The polymerization of propene to polypropylene progresses through a radical mechanism. Complete the propagation step of the reaction mechanism diagram by drawing in the missing lone pairs, radical electrons, atomic charges, and electron-flow arrows where appropriate. 2...
  15. E

    So it’s not a plausible mechanism for polymerization.

    What follows is a suggested mechanism for base catalyzed acetone polymerization which is based on simple nucleophilic addition series. I have divided the mechanism into three steps, shown below. In step 1, the reaction is initialized by a base catalyzed initiation into ketone-enolate resonance...
  16. A

    Q. about the Cossee-Arlman mechanism in alkene polymerization

    Starting out with TiCl4 and triethylaluminum, I understand how the triethylaluminum alkylates the TiCl4 and creates a polymeric TiCl3, but then an ethene molecule coordinates with a vacant site on the alkylated TiCl3? I thought titanium's highest oxidation state was +4?
  17. E

    High speed polymerization reaction initiated by the action

    So what's happening is a high speed polymerization reaction initiated by the action of laser light. An infrared beam moniters the amount of unreacted acrylate double bonds. But what is an acrylate double bond? Am I correct in saying that a double bond absorbs IR radiation? The double bond...
  18. P

    Alpha Lipoic Acid polymerization question

    I am taking R-Alpha Lipoic Acid (RALA) as a supplement, however apparently it's very unstable and polymerizes at about 40-50 degrees C and becomes unabsorbable. Apparently it also polymerizes when it reaches the stomach. There are also stabilized forms such as Na-RALA and K-RALA. Now what i want...
  19. M

    Ziegler-Natta polymerization of ethylene

    Hi everyone, Does anyone know much about the Ziegler-Natta polymerization reaction? I used Spartan to find a transition state structure (specifically for the insertion of ethylene into Cp2ZrCH3+), and I'm supposed to use a molecular vibration (with an imaginary frequency, corresponding to...
  20. M

    Why Do Bubbles Form in Methyl Methacrylate Reaction at High Temperatures?

    Homework Statement When heating the methyl methacrylate reaction (methyl methacrylate and dibenzoyl peroxide) to 90-95oC, why do bubbles evolve from the solution? Homework Equations None The Attempt at a Solution I'm not sure why the bubbles form. Any hints or helpful websites?
  21. V

    Polymerization - Synthesis of Orlon

    Hey, Im doing a project on organic Chemistry and I need to find the structure for the synthesis of Orlon. However, it seems very hard to find this info on the net. I've googled everything but no info. Can somebody please help me find a website with this information? I think there may be a...
  22. V

    What is the structure of the polymer produced by this type of polymerization?

    Hi, I have done simple polymerization but none like this. Can you please help me on this question. What would be the structure of the polymer produced by the polymerization of (see attached picture) Draw 3 repeating units. Thanks so much