Related Experiment Video
Updated: Jun 22, 2026
06:55
Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Non-local polymerization driven diffusion based model: general dependence of the polymerization rate to the exposure
Optics Express
|May 26, 2009
Summary
This study examines a nonlocal diffusion model for photopolymer grating formation. It investigates how polymerization rate dependence on light intensity affects grating harmonics and compares these effects to diffusion variations.
Area of Science:
- Photopolymerization science
- Holographic grating formation
- Nonlocal diffusion modeling
Background:
- The nonlocal diffusion model by Sheridan et al. explains grating formation in photopolymers.
- This model successfully accounts for experimental observations like diffraction efficiency cutoff at high spatial frequencies.
Purpose of the Study:
- To analyze the predictions of the nonlocal diffusion model under general polymerization rate dependencies on light intensity patterns.
- To investigate the impact of these dependencies on harmonic components of polymer concentration.
- To study the influence of fringe visibility on harmonic components and compare these effects with variations in diffusion parameters (RD and sigmaD).
Main Methods:
- Theoretical examination of the nonlocal diffusion model.
- Analysis of polymerization rate dependence on light intensity.
- Investigation of harmonic components of polymer concentration.
- Comparison with diffusion parameter variations (RD, sigmaD).
Main Results:
- The study explores how varying polymerization rate dependencies influences the formation of different harmonic components within the photopolymer grating.
- It quantifies the effect of fringe visibility on these harmonic components.
- A comparative analysis is performed between the effects of polymerization rate dependencies and changes in diffusion coefficients (RD, sigmaD).
Conclusions:
- The findings provide deeper insights into the factors governing grating formation in photopolymers, particularly the role of intensity-dependent polymerization.
- Understanding these effects is crucial for optimizing photopolymer materials for holographic applications.
- The research highlights the interplay between polymerization kinetics and diffusion in determining grating characteristics.
Related Concept Videos
01:08Molecular Weight of Step-Growth Polymers
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...
01:10Polymers: Molecular Weight Distribution
For any given polymer, the weight average molecular weight (Mw) is higher than, if not equal to, the number average molecular weight (Mn). The only situation in which the weight average molecular weight and the number average molecular weight are equal is when a polymer consists only of chains with equal molecular weight. However, this never happens in a synthetic polymer, since it is difficult to control the polymerization process up to a molecular level with accuracy to a hundred percent.
01:24Determination of Molar Masses of Polymers I
Polymerization produces macromolecules with a range of chain lengths due to the random nature of molecular growth processes. As chains form and terminate at different stages, a single polymer sample contains molecules of varying sizes rather than a uniform structure. This variability is described using average molar masses and distribution-related parameters, which together provide a comprehensive understanding of polymer characteristics.The distribution of molar masses plays a critical role in...
00:57Cationic Chain-Growth Polymerization: Mechanism
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the generated carbocation,...
01:03Step-Growth Polymerization: Overview
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...
02:34Polymers
The word polymer is derived from the Greek words “poly” which means “many” and “mer” which means “parts”. Polymers are long chains of molecules composed of repeating units of smaller molecules, known as monomers. They either occur naturally, such as DNA and proteins, or can be constructed synthetically, like plastics. They have varied structural characteristics, such as linear chains, branched chains, or complex networks, that contribute to the properties that they exhibit. Additionally,...