Monomer Addition
Monomer Addition - Related Videos
10:01
Kinetics of Addition Polymerization to Polydimethylsiloxane
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2023
Source: Kerry M. Dooley and Michael G. Benton, Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA Polymers are molecules consisting of many repeating monomer units that are chemically bonded into long chains. They exhibit a broad range of physical properties, which are affected by their chemical structure, molecular weight and degree of polymerization. The polymer industry manufactures thousands of raw materials used in a broad variety of commercial products.1,2 The...
09:47
Isolation and Compositional Analysis of Plant Cuticle Lipid Polyester Monomers
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Cited by 32 •
2015
Lipid polyesters constitute the structural components of two cell wall modifications, the plant cuticle and suberin-containing diffusion barriers. In this video, we describe a method to depolymerize cutin from whole delipidated leaves. The method can be applied to investigating mutants compromised in either cutin or suberin biosynthesis.
01:27
Conjugate Addition (1,4-Addition) vs Direct Addition (1,2-Addition)
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2025
α,β-Unsaturated carbonyl compounds with two electrophilic sites, the carbonyl carbon, and the β carbon, are susceptible to nucleophilic attack via two modes: conjugate or 1,4-addition and direct or 1,2-addition. Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon. Direct addition products are formed faster owing to...
01:08
Conjugate Addition of Enolates: Michael Addition
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2023
The attack of a nucleophile at the β carbon of an α,β-unsaturated carbonyl compound is called conjugate addition. Conjugate addition reactions of active methylene compounds, such as β-diketones, β-keto esters, β-keto nitriles, and α-nitro ketones, are called Michael addition reactions. The reaction is catalyzed by a base that abstracts the acidic methylene hydrogen, generating a doubly-stabilized enolate ion that serves as the nucleophile or the Michael donor. The base employed depends on the...
09:02
Using Polystyrene-block-poly(acrylic acid)-coated Metal Nanoparticles as Monomers for Their Homo- and Co-polymerization
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Cited by 1 •
2015
We report protocols for “polymerizing” various types of polymer-encapsulated metal nanoparticles into long chains of “homo-“ and “co-polymers”.
FAQs
The initiator establishes the active center that starts chain growth. Depending on the system, that center is a radical, cation, or anion, and it attacks the monomer’s carbon–carbon double bond. Opening that bond creates a new growing chain end, allowing successive monomers to join through repeated propagation.
The double bond provides the reactive site that the active chain end can attack. Its opening converts the monomer into a unit connected to the growing chain while leaving a new active end available for further addition. This repeating sequence links many monomers and supports formation of high-molecular-weight polymer chains.
In Monomer Addition, the monomer units become part of the polymer chain without eliminating a small molecule during chain growth. The process therefore proceeds through repeated bond opening and propagation rather than a sequence that releases a small molecular byproduct. This distinction helps explain the mechanism used to produce many synthetic polymer materials.
Temperature, initiator concentration, and other reaction conditions influence how the growing chains develop. Adjusting these factors helps chemists regulate polymer structure, which in turn affects material properties. Careful control is therefore important when the target material must function as a plastic, elastomer, coating, or fiber.
A typical sequence begins by introducing an initiator capable of generating a radical, cation, or anion. The active species attacks the monomer’s carbon–carbon double bond, and the resulting chain end adds additional monomer units through propagation. Chemists then control temperature, initiator concentration, and related conditions to guide the resulting polymer structure.
This chain-growth approach supports the preparation of plastics, elastomers, coatings, and fibers. Its importance extends beyond producing a polymer because reaction control can be used to influence the structure and resulting material properties. Chemistry researchers therefore apply it when investigating how polymer formation conditions affect useful synthetic materials.