Related papers: Water-polymer coupling induces a dynamical transit…
The molecular mechanism of the solvent motion that is required to instigate the protein structural relaxation above a critical hydration level or transition temperature has yet to be determined. In this work we use quasi-elastic neutron…
Temperature-responsive properties of surface-attached poly(N-isopropylacrylamide) (PNIPAM) network films with well-controlled chemistry are investigated. The synthesis consists of cross-linking and grafting preformed ene-reactive polymer…
The influence of shape fluctuations on deformable thermosensitive microgels in aqueous solution is investigated by dynamic light scattering (DLS) and depolarized dynamic light scattering (DDLS). The systems under study consist of a solid…
For a wide range of modern soft functional materials the selective transport of sub-nanometer-sized molecules (`penetrants') through a stimuli-responsive polymeric membrane is key to the desired function. In this study, we investigate the…
We synthesize thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) colloidal microgel particles of different stiffnesses by controlling the concentration of crosslinker in a one-pot synthesis method. We employ oscillatory rheology and…
Water plays a major role in bio-systems, greatly contributing to determine their structure, stability and even function. It is well know, for instance, that proteins require a minimum amount of water to be functionally active. Since the…
Poly(N-isopropylacrylamide) (PNIPAM) is a temperature-responsive polymer that undergoes large volumetric deformations through a transition from a swollen to a collapsed state at the volume phase transition temperature (VPTT). Locally, these…
The inner structure of polymeric particles critically influences their phase behavior and functionality, governing their mechanical properties and their physical and chemical interactions. For thermoresponsive microgels, i.e. colloidal…
Hypothesis: The peculiar swelling behaviour of poly(N-isopropylacrylamide) (PNIPAM)-based responsive microgels provides the possibility to tune both softness and volume fraction with temperature, making these systems of great interest for…
We investigate the co-nonsolvency of poly-N-isopropyl acrylamide (PNiPAM) in different water-alcohol mixtures and show that this phenomenon is due to two distinct solvation contributions governing the phase behavior of PNiPAM in the…
This is an integrated experimental and theoretical study of the dynamics and rheology of self-crosslinked, slightly charged, temperature responsive soft Poly(N-isopropylacrylamide) (pNIPAM) microgels over a wide range of concentration and…
Using an activation mechanism reproducing facilitation, a dynamic phase transition triggered by a few active molecules was recently found in a supercooled model liquid. Prompted by this finding we investigate the presence of a similar…
Thermoresponsive polymer architectures have become integral building blocks of 'smart' functional materials in modern applications. For a large range of developments, e.g., for drug delivery or nanocatalytic carrier systems, the selective…
The utility of non functionalized poly(N-isopropylacrylamide) (pNIPAM) microgels in physiological and environmental applications is strictly dependent on their reversible thermoresponsiveness and stability in saline media. Despite their…
PNIPAm microgels synthesized via free radical polymerization (FRP) are often considered as neutral colloids in aqueous media, although it is well known, since the pioneering work of Pelton and coworkers [Langmuir 1989, 5, 816-818], that the…
Combining elastic incoherent neutron scattering and differential scanning calorimetry, we investigate the occurrence of the volume phase transition (VPT) in very concentrated PNIPAM microgel suspensions, from a polymer weight fraction of…
Studies of liquid water in its supercooled region have led to many insights into the structure and behavior of water. While bulk water freezes at its homogeneous nucleation temperature of approximately 235 K, for protein hydration water,…
Polyamide 6,6 (PA66) is a key engineering polymer, whose unique mechanical properties arise from strong interchain hydrogen bonding. However, its hygroscopic nature makes it highly sensitive to water uptake, which markedly alters its…
A central quantity in the design of functional hydrogels used as nanocarrier systems, for instance for drug delivery or adaptive nanocatalysis, is the partition ratio, which quantifies the uptake of a molecular substance by the polymer…
Water is essential for the activity of proteins. However, the effect of the properties of water on the behavior of proteins is only partially understood. Recently, several experiments have investigated the relation between the dynamics of…