Related Experiment Video
Updated: May 28, 2026

Characteristics of Precipitation-formed Polyethylene Glycol Microgels Are Controlled by Molecular Weight of Reactants
Published on: December 23, 2013
Methylene glycol-sulfite pH-clocks for the time-programming of soft materials: advantages, limitations, and yet
1Institute for Building Materials, Department of Civil, Environmental and Geomatic Engineering, ETH Zürich, Laura-Hezner-Weg 7, 8093 Zürich, Switzerland. guidop@ethz.ch.
Abstract:
Coupling nonlinear reaction networks with soft matter building blocks holds great potential for the design of life-mimicking, time-programmable dissipative self-assembly systems. In this regard, clock reactions are especially useful triggers since they allow to autonomously generate in situ chemical stimuli such as pH changes. The methylene glycol-sulfite (MGS) is a well-known acid-to-base pH-clock reaction which is able to produce sharp and intense pH jumps (up to 5 pH units) after a reliable, yet relatively short (tens of seconds rather than minutes), induction time. Here, after an introductory discussion on the main chemical aspects of MGS and MGS-based systems, their applications for the time-programming of soft matter will be showcased - from micelles, vesicles, and droplets to supramolecular aggregates, polymers and gels. Hopefully, this will help attracting more attention and foster research on the broader field of materials programming with chemical reaction networks.
More Related Videos
12:07Fabricating Degradable Thermoresponsive Hydrogels on Multiple Length Scales via Reactive Extrusion, Microfluidics, Self-assembly, and Electrospinning
Published on: April 16, 2018
11:38Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
Related Concept Videos
pH
pH Scale
Determining the pH of Salt Solutions
pH
Retarders
The function of retarders is to delay the setting of concrete, and this effect can be measured using a penetration test. The retardation process involves adding...
Carbonation Shrinkage
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction facilitates the...