In order to understand how soft-materials react to deformation at the molecular level, a group of researchers has developed a new technique in laboratory that challenges the traditional understanding of soft materials.
In the recently published paper in the journal Physics Review Letters, the researcher pointed out that understanding the soft materials’ reactions to rapid deformation is key to develop next generation materials. Previous researches for instance, attempted to characterize the deformation mathematically. However, they were unable to relate any well-defined microstructural observations to mathematical models.
“In our study, we wanted to measure both the structural and mechanical properties of polymers during deformation, directly shedding light on the origin of unique mechanical properties,” said Johnny Ching-Wei Lee, a graduate student and study co-author. “We thought perhaps it was best to try and use direct observations to explain the complex physics.”
In order to solve the problem, the researchers combined traditional tools for measuring stress and neutron scattering, a technique to understand the deformation at a molecule level. Interestingly, the researchers were able to solve the problem mentioned above.
“With simultaneous neutron scattering and flow measurements, we are able to directly correlate structure and mechanical properties with a time resolution on the order of milliseconds, ” said study co-author Katie Weigandt, a researcher from the National Institute of Standards and Technology Center for Neutron Science. “This approach has led to fundamental understanding in a wide range of nanostructured complex fluids, and in this work, validates new approaches to making polymer flow measurements. ”
Lee added, “Previous research had assumed that the amount of applied deformation at the macroscale is what soft materials experience at the microscale. But the neutron-scattering data from our study clearly shows that it is the deformation that can be recovered that matters because it dictates the whole response, in terms of macroscopic flow – something that was previously unknown.”
The researchers expect that their latest findings will help others to understand different phenomena in polymers’ research and help to develop soft materials that can meet different needs.