Related Experiment Video
Updated: Jul 4, 2025
07:41
Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging
Published on: July 19, 2016
7.7K
On the Swelling of Polymer Network Strands
Michael Lang1, Reinhard Scholz1
1Leibniz Institute of Polymer Research Dresden, Hohe Straße 6, 01069, Dresden, Germany.
Macromolecular Rapid Communications
|February 7, 2024
Summary
Computer simulations reveal polymer network strands exhibit non-ideal conformations upon swelling. The total chain size change results from combined fluctuating and elastic contributions during swelling.
Area of Science:
- Polymer Science
- Computational Chemistry
- Materials Science
Background:
- Polymer networks are crucial in various materials.
- Understanding polymer chain conformations under different conditions is essential.
- Previous studies often simplified network strand behavior.
Purpose of the Study:
- To analyze polymer network strand conformations using large-scale computer simulations.
- To compare strand behavior at preparation conditions versus equilibrium swelling.
- To elucidate the contributions of fluctuating and elastic segments to chain size changes.
Main Methods:
- Employed large-scale computer simulations.
- Analyzed polymer volume fraction (ϕ) at preparation (ϕ₀) and equilibrium (ϕ < ϕ₀).
- Investigated chain conformations and scaling exponents.
Main Results:
- Network strands are weakly stretched and partially swollen at preparation.
- Equilibrium swelling leads to non-ideal conformations with a scaling exponent near 7/10.
- Chain size comprises fluctuating and elastic contributions, with distinct swelling behaviors.
Conclusions:
- Equilibrium swelling significantly alters polymer network strand conformations.
- Both fluctuating and elastic components contribute to the overall chain swelling.
- The findings provide insights into polymer network elasticity and swelling phenomena.
Related Concept Videos
01:08Molecular Weight of Step-Growth Polymers
2.2K
Step growth polymerization involves bi or multifunctional monomers. Bifunctional monomers react to form linear step growth polymers, whereas multifunctional monomers react to form non-linear or branched polymers.
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
2.2K
01:14Polymer Classification: Architecture
2.7K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
2.7K
01:03Step-Growth Polymerization: Overview
3.5K
Step-growth or condensation polymerization is a stepwise reaction of bi or multifunctional monomers to form long-chain polymers. As all the monomers are reactive, most of the monomers are consumed at the early stages of the reaction to form small chains of reactive oligomers, which then combine to form long polymer chains in the late stages. Hence, the reaction has to proceed for a long time to achieve high molecular weight polymers.
Many natural and synthetic polymers are produced by...
Many natural and synthetic polymers are produced by...
3.5K
01:04Anionic Chain-Growth Polymerization: Mechanism
2.0K
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...
2.0K
01:21Polymer Classification: Crystallinity
2.9K
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
2.9K
01:17Radical Chain-Growth Polymerization: Chain Branching
1.9K
The skeletal structure of polymers synthesized via radical polymerization is always branched. For example, the polymerization of ethylene by radical polymerization results in a low-density grade of polyethylene with a heavily branched skeletal structure. Here, the radical site abstracts hydrogen from the growing chain, and the radical site shifts from the end (a primary carbon center) to anywhere within the growing chain (a secondary carbon center). Consequently, the part of the chain from the...
1.9K