usually differ from macrogels in their properties), the network density, the presence
of additional dangling chains and free ends of polymer chains impact the stimuli
threshold in this class of stimuli-responsive materials. Most SRPS are designed in a
form of polymer solutions, mixtures and dispersions. Thus, the polymer concentration and a type of a solvent also influence the response of the system to a
stimulus.
Besides single macromolecules and gels, polymer-modified surfaces, polymer
micelles and vesicles can also be used as SRPS—see Fig. 8.1. However, our further
considerations will be limited only to solutions of linear macromolecules and gels.
The first ones are important not only as stimuli-responsive materials, but also (or
even primarily) as building blocks for more complex systems. Gels should be
considered as the most popular and promising smart materials. In these systems, the
intermolecular interactions between components constitute the crucial issue.
The roots of polymer solutions theory date back to the 1940s and Huggins [39]
and Flory’s works [40–44] developed later by Stockmayer and Krigbaum [45–49].
A detailed description of the Flory’s theory exceeds the framework of this study,
but it can be found in many polymer handbooks [50–52]. A broad review of
development of Flory’s theory has also been done lately by Bhattacharjee et al.
[43]. However, it is important to notice that polymer solubility (especially in case of
Fig. 8.1 Selected mechanisms of responsivity to stimuli in water–polymer systems: a formation
of micelles and vesicles by co-polymers capable of self-assembling; b surfaces decorated by
stimuli-responsive polymer chains able to form ‘mushrooms’ and ‘pancakes’ conformations (this
can be realized on macro-, micro- as well as nanoscale, for example by nanoparticle decoration);
c hydrogels including micro- and nanogels
8 Vibrational Spectroscopy in Analysis of Stimuli-Responsive …
225
of additional dangling chains and free ends of polymer chains impact the stimuli
threshold in this class of stimuli-responsive materials. Most SRPS are designed in a
form of polymer solutions, mixtures and dispersions. Thus, the polymer concentration and a type of a solvent also influence the response of the system to a
stimulus.
Besides single macromolecules and gels, polymer-modified surfaces, polymer
micelles and vesicles can also be used as SRPS—see Fig. 8.1. However, our further
considerations will be limited only to solutions of linear macromolecules and gels.
The first ones are important not only as stimuli-responsive materials, but also (or
even primarily) as building blocks for more complex systems. Gels should be
considered as the most popular and promising smart materials. In these systems, the
intermolecular interactions between components constitute the crucial issue.
The roots of polymer solutions theory date back to the 1940s and Huggins [39]
and Flory’s works [40–44] developed later by Stockmayer and Krigbaum [45–49].
A detailed description of the Flory’s theory exceeds the framework of this study,
but it can be found in many polymer handbooks [50–52]. A broad review of
development of Flory’s theory has also been done lately by Bhattacharjee et al.
[43]. However, it is important to notice that polymer solubility (especially in case of
Fig. 8.1 Selected mechanisms of responsivity to stimuli in water–polymer systems: a formation
of micelles and vesicles by co-polymers capable of self-assembling; b surfaces decorated by
stimuli-responsive polymer chains able to form ‘mushrooms’ and ‘pancakes’ conformations (this
can be realized on macro-, micro- as well as nanoscale, for example by nanoparticle decoration);
c hydrogels including micro- and nanogels
8 Vibrational Spectroscopy in Analysis of Stimuli-Responsive …
225