Related Experiment Video
Updated: Aug 14, 2026
11:17
Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
Published on: January 19, 2016
Chiral-mechanical transitions in topologically imprinted elastomers
D J Burridge1, Y Mao, M Warner
1Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, UK.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 31, 2005
Summary
This study models chirally imprinted nematic elastomers, finding that director rotation leads to a conical state when the rubber matrix deforms. Transitions between imprinting efficiencies involve coupled, discontinuous director rotation.
Area of Science:
- Materials Science
- Polymer Physics
- Soft Matter Physics
Background:
- Chirally imprinted nematic elastomers exhibit unique optical and mechanical properties.
- Previous models focused on director alignment without considering spontaneous matrix deformation.
- Understanding director behavior is crucial for designing advanced elastomer materials.
Purpose of the Study:
- To extend existing models of chirally imprinted nematic elastomers.
- To incorporate director rotation and spontaneous rubber matrix deformation.
- To investigate the impact of these factors on elastomer behavior across different imprinting efficiencies.
Main Methods:
- Theoretical modeling of nematic elastomers.
- Inclusion of an additional degree of freedom for director rotation (π/2-θ).
- Analysis of spontaneous deformation in the rubber matrix.
Main Results:
- The director array adopts a conical state due to spontaneous matrix deformation.
- This conical state occurs in both low and high imprinting efficiency regimes.
- The transition between imprinting efficiency regimes is coupled to the director rotation angle θ.
Conclusions:
- Spontaneous matrix deformation significantly influences director behavior in nematic elastomers.
- Director rotation and imprinting efficiency are interdependent.
- Discontinuous director rotation occurs at transitions between imprinting efficiency regimes, highlighting complex material responses.
Related Concept Videos
02:05Prochirality
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
02:33Stereoisomerism of Cyclic Compounds
In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
02:25Chirality
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
02:30Chirality in Nature
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid. The...
00:58¹H NMR Chemical Shift Equivalence: Enantiotopic and Diastereotopic Protons
Replacing each alpha-hydrogen in chloroethane by bromine (or a different functional group) yields a pair of enantiomers. Such protons are called prochiral or enantiotopic and are related by a mirror plane. Enantiotopic protons are chemically equivalent in an achiral environment. Because most proton NMR spectra are recorded using achiral solvents, enantiotopic hydrogens yield a single signal.
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...
01:28Classification and Mechanical Properties of Synthetic Polymers
Synthetic polymers are classified as elastomers, fibers, or plastics based on their crystallinity. Crystallinity, the degree of long-range order in the solid state, influences the mechanical properties (stretching or contracting) of elastomers. Elastomers are flexible polymers that can expand or contract easily upon the application of an external force. They have numerous crosslinks that pull them back into their original shape when stress is removed. Silicones, for instance, are highly elastic...