scholarly journals Thermoresponsive Polymers: Thermoresponsive Polymer Induced Sweating Surfaces as an Efficient Way to Passively Cool Buildings (Adv. Mater. 39/2012)

2012 ◽  
Vol 24 (39) ◽  
pp. 5277-5277 ◽  
Author(s):  
A. C. C. Rotzetter ◽  
C. M. Schumacher ◽  
S. B. Bubenhofer ◽  
R. N. Grass ◽  
L. C. Gerber ◽  
...  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kenichi Nagase ◽  
Yuta Umemoto ◽  
Hideko Kanazawa

AbstractTemperature-responsive chromatography using thermoresponsive polymers is innovative and can control analyte retention via column temperature. Analyte elution behavior in this type of chromatography depends on the modified thermoresponsive polymer and the structure of the base materials. In the present study, we examine the effect of the pore diameter of silica beads on analyte elution behavior in temperature-responsive chromatography. Poly(N-isopropylacrylamide-co-n-butyl methacrylate) hydrogel was applied to beads of various pore sizes: 7, 12, and 30 nm. Almost the same amount of copolymer hydrogel was applied to all beads, indicating that the efficiency of copolymer modification was independent of pore size. Analyte retention on prepared beads in a packed column was observed using steroids, benzodiazepines, and barbiturates as analytes. Analyte retention times increased with temperature on packed columns of 12- and 30-nm beads, whereas the column packed with 7-nm beads exhibited decreased retention times with increasing temperature. The difference in analyte elution behavior among the various pore sizes was attributed to analyte diffusion into the bead pores. These results demonstrate that bead pore diameter determines temperature-dependent elution behavior.


2020 ◽  
Author(s):  
Anna Constantinou ◽  
Valeria Nele ◽  
James Doutch ◽  
Roman Moiseev ◽  
Vitaliy Khutoryanskiy ◽  
...  

Abstract Thermoresponsive polymers featuring the appropriate combination of structural characteristics, i.e. architecture, composition, and molar mass (MM), can form physically crosslinked networks in a solvent upon changes in temperature. This fascinating class of polymers finds utility in various sectors such as formulation science and tissue engineering. Here, we report a novel thermoresponsive triblock terpolymer which out-performs the most commonly used and commercially available thermoresponsive polymer, Poloxamer P407 (also known as Pluronic® F127) in terms of gelation concentration. Specifically, the in-house synthesised polymer forms gels at lower concentrations that is an advantage in biomedical applications. To elucidate the differences in their macroscale gelling behaviour, we investigate their micellization via differential scanning calorimetry, and their nanoscale self-assembly behaviour in detail by means of small-angle neutron scattering by simultaneously recording their rheological properties (Rheo-SANS). Two different gelation mechanisms for the two polymers are revealed and proposed. Ex vivo gelation study upon intracameral injections demonstrated excellent potential for its application to improve drug residence in the eye.


2019 ◽  
Vol 21 (12) ◽  
pp. 6588-6599 ◽  
Author(s):  
Sebastian Milster ◽  
Richard Chudoba ◽  
Matej Kanduč ◽  
Joachim Dzubiella

Molecular dynamics study on the solute adsorption to thermoresponsive polymers estimating the cross-link impact on particle partitioning in swollen hydrogels.


2016 ◽  
pp. S191-S201
Author(s):  
M. HRUBÝ ◽  
J. KUČKA ◽  
J. PÁNEK ◽  
P. ŠTĚPÁNEK

For many important research topics in polymer science the use of radionuclides brings significant benefits concerning nanotechnology, polymer drug delivery systems, tissue engineering etc. This contribution describes important achievements of the radionuclide laboratory at Institute of Macromolecular Chemistry of the Academy of Sciences of the Czech Republic (IMC) in the area of polymers for biomedical applications. Particular emphasis will be given to water-soluble polymer carriers of radionuclides, thermoresponsive polymer radionuclide carriers, thermoresponsive polymers for local brachytherapy, polymer scaffolds modified with (radiolabeled) peptides and polymer copper chelators for the therapy of Wilson´s disease.


2018 ◽  
Vol 71 (7) ◽  
pp. 477 ◽  
Author(s):  
Sushilkumar A. Jadhav ◽  
Dominique Scalarone

Porous silica particles grafted with various stimuli-responsive polymers are investigated with great interest for their use as smart pharmaceutical nanocarriers in advanced drug delivery systems (DDS). In particular, porous silica particles grafted with thermoresponsive polymers that exhibit thermally triggered on/off gating mechanisms have shown improved performance as hybrid DDS capable of controlling the release of different drugs in various mediums which resemble complex biological environments. In addition, the tuning of the drug release profiles as per requirements has proved possible with modifications to the porous core and the grafted thermoresponsive polymers. This highlight presents a brief discussion of basic preparation techniques and some recent significant developments in the field of thermoresponsive polymer grafted porous silica particles as smart pharmaceutical nanocarriers.


Soft Matter ◽  
2018 ◽  
Vol 14 (16) ◽  
pp. 3096-3104 ◽  
Author(s):  
R. de Ruiter ◽  
L. Royon ◽  
J. H. Snoeijer ◽  
P. Brunet

Spreading and solidification of liquid droplets are elementary processes of relevance for additive manufacturing. With simple drop spreading experiments of a thermoresponsive polymer solution, we found that the final shape is ruled by the difference between the substrate temperature and the gelation temperature. Unexpectedly, spreading also stops below the gelation temperature, due to an increase in polymer concentration induced by evaporation near the contact line.


2016 ◽  
Vol 4 (39) ◽  
pp. 6381-6397 ◽  
Author(s):  
Kenichi Nagase ◽  
Teruo Okano

In this review, bioseparations using thermoresponsive polymers are summarized. Thermoresponsive chromatography for separating bioactive compounds and proteins, and cell separations using thermoresponsive polymers and their properties are reviewed.


2021 ◽  
Author(s):  
Maximilian Felix Toni Meier ◽  
Franck Thetiot ◽  
Narsimhulu Pittala ◽  
Ingo Lieberwirth ◽  
Cleiton Kunzler ◽  
...  

We have designed novel macromolecular coordination ligands (MCLs) by conjugation of thermoresponsive polymers based on poly(N-isopropylacrylamide) (M ̅_n around 3 to 25 kg∙mol-1) with 1,2,4-triazole coordination sites. These triazole units...


Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 90
Author(s):  
Łukasz Otulakowski ◽  
Maciej Kasprów ◽  
Aleksandra Strzelecka ◽  
Andrzej Dworak ◽  
Barbara Trzebicka

Thermoresponsive polymers are a promising material for drug nanocarrier preparation, which makes the study of their aggregation in physiological conditions very important. In this paper, the thermal behaviour of the thermoresponsive polymers poly(N-isopropylacrylamide), poly(2-isopropyl-2-oxazoline-co-2-n-propyl-2-oxazoline) and poly[(2-hydroxyethyl methacrylate)-co-oligo(ethylene glycol) methyl ether methacrylate] were studied in phosphate buffer (PBS) and solutions of its salts in concentration as in PBS. The thermal response of the polymers was measured using UV-Vis and dynamic light scattering (DLS). The salts shifted the cloud point temperature (TCP) of the (co)polymers to higher values compared to the TCP of aqueous polymer solutions. In PBS and NaCl solutions, all polymers exhibited an unexpected and previously unreported transmittance profile. During heating, an additional aggregation of polymers appeared above the TCP accompanied by the formation of a precipitate. In monosodium phosphate solutions and pure water, the studied polymers showed lower critical solution temperature (LCST-type) behaviour. DLS measurements showed that a salt influenced the size of the resulting polymer particles. The sizes and stability of particles depended on the heating rate. In PBS and NaCl solutions, the size of particles in the dispersion decreased above 60 °C, and the precipitate appeared on the bottom of the cuvette. The additional aggregation of polymer and its falling out of solution may hinder the removal of carriers from the body and has to be taken into account when preparing nanocarriers.


2021 ◽  
Vol 11 (8) ◽  
pp. 3379
Author(s):  
Hyung Ju Lee ◽  
Chan Ho Jeong ◽  
Dae Yun Kim ◽  
Chang Kyoung Choi ◽  
Seong Hyuk Lee

The present study aims to measure the solid–liquid interface temperature of an evaporating droplet on a heated surface using a thermoresponsive polymer. Poly(N-isopropylacrylamide) (pNIPAM) was used owing to its sensitive optical and mechanical properties to the temperature. We also measured the refractive index variation of the pNIPAM solution by using the surface plasmon resonance imaging (SPRi). In particular, the present study proposed a new method to measure the solid–liquid interface temperature using the correlation among reflectance, refractive index, and temperature. It was found that the reflectance of a pNIPAM solution decreased after the droplet deposition. The solid–liquid interface temperature, estimated from the reflectance, showed a lower value at the center of the droplet, and it gradually increased along the radial direction. The lowest temperature at the contact line region is present because of the maximum evaporative cooling. Moreover, the solid–liquid interface temperature deviation increased with the surface temperature, which means solid–liquid interface temperature should be considered at high temperature to predict the evaporation flux of the droplet accurately.


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