Equilibrium swelling of multi-stimuli-responsive copolymer gels

2021 ◽  
pp. 104623
Author(s):  
Aleksey D. Drozdov ◽  
Jesper deClaville Christiansen
Keyword(s):  
Stimuli Responsive ◽  
Equilibrium Swelling ◽  
Copolymer Gels

Modeling Equilibrium Swelling of a Dual pH- and Temperature-Responsive Core/Shell Hydrogel

2016 ◽  
Vol 08 (03) ◽  
pp. 1650039 ◽  
Author(s):  
N. Hamzavi ◽  
A. D. Drozdov ◽  
Y. Gu ◽  
E. Birgersson
Keyword(s):  
Ph Sensitivity ◽  
Core Shell ◽  
Polymer Gel ◽  
Stimuli Responsive ◽  
Degree Of Ionization ◽  
High Ph ◽  
The Core ◽  
Ionic Core ◽  
Ph Values ◽  
Equilibrium Swelling

The equilibrium swelling of a dual stimuli-responsive core/shell hydrogel is studied by a thermodynamic model. This hydrogel shows thermo-sensitivity as well as pH-sensitivity. The model captures the inhomogeneous swelling of core/shell hydrogels and also, accounts for temperature and pH sensitivity. The predictions of this model are verified with the swelling experiments of a core/shell microgel comprising poly N-isopropyl acrylamide (pNIPAM) and acrylic acid (AAc). The model calculates the equilibrium swelling within the ionic core and the neutral shell. Simulation results can reproduce the equilibrium swelling-temperature curves of this microgel at different pH values considering the delay in the volume phase transition temperature (VPTT) of the ionic polymer gel (pNIPAM-co-AAc) in the core. Two transition points are found in the equilibrium swelling behavior of the hydrogel akin to the VPTTs of the core and shell domains at high pH values of bath solutions. Likewise, the degree of ionization in the core domain is predicted to have a two-step transition behavior corresponding to the VPTTs of the core and shell domains at high pH values of bath solutions. It is shown that the equilibrium swelling of the ionic core is mainly influenced by the electrostatic repulsion between bound charges rather than the ionic pressure. Furthermore, it is determined that the maximum radial stress occurs at the core/shell interface and reaches its maximum value about the VPTT of the core.

scholarly journals Stimuli Responsive Hydrogels: NIPAM/AAm/Carboxylic Acid Polymers

2019 ◽  
Vol 27 (2) ◽  
pp. 155-184 ◽  
Author(s):  
Yasemin Işikver ◽  
Dursun Saraydin
Keyword(s):  
Thermal Analyses ◽  
The Body ◽  
Polymerization Reaction ◽  
Solution Temperature ◽  
Stimuli Responsive ◽  
Scanning Calorimetry ◽  
Equilibrium Swelling ◽  
Different Temperatures ◽  
Swelling Studies ◽  
Responsive Hydrogels

Abstract Stimuli-responsive hydrogels (SRH) were prepared by using monomers (i.e. N-isopropyl acrylamide; NIPAM and acrylamide; AAm), co-monomers (i.e. methacrylic acid; MPA or mesaconic acid; MFA) and a crosslinker (N, N’-methylene bisacrylamide; N-Bis). SRH have been prepared by thermal free radical polymerization reaction in aqueous solution. Spectroscopic and thermal analyses such as Fourier Transform Infrared Spectroscopy, thermogravimetric analysis and differential scanning calorimetry analysis were performed for SRH characterization. The equilibrium swelling studies by gravimetrically were carried out in different solvents, at the solutions, temperature, pH, and ionic strengths to determine their effect on swelling characteristic of the hydrogels. In addition, cycles equilibrium swelling studies were made with the solutions at different temperatures and at different pH. NIPAM/AAm hydrogel exhibits a lover critical solution temperature (LCST) at 28 oC, whereas NIPAM/AAm-MPA and NIPAM/AAm-MFA hydrogels exhibit a LCST at 31 C and 35 oC, respectively, and the LCST of NIPAM/AAm-MFA hydrogel is close to the body temperature.

scholarly journals Precise Control over the Rheological Behavior of Associating Stimuli-Responsive Block Copolymer Gels

Gels ◽  
2015 ◽  
Vol 1 (2) ◽  
pp. 235-255 ◽  
Author(s):  
Jérémy Brassinne ◽  
Flanco Zhuge ◽  
Charles-André Fustin ◽  
Jean-François Gohy
Keyword(s):  
Block Copolymer ◽  
Rheological Behavior ◽  
Stimuli Responsive ◽  
Precise Control ◽  
Copolymer Gels

Mathematical Modeling of Hydrogels for Microfluidic Flow Control

2009 ◽  
Vol 74 ◽  
pp. 33-36 ◽  
Author(s):  
Jundika Candra Kurnia ◽  
Erik Birgersson ◽  
Arun Sadashiv Mujumdar ◽  
Lee Ching Quah
Keyword(s):  
Mathematical Modeling ◽  
Power Supply ◽  
Stimuli Responsive ◽  
Ph Responsive ◽  
Microfluidic Flow ◽  
Equilibrium Swelling ◽  
Conservation Of Momentum ◽  
External Power ◽  
Responsive Hydrogels ◽  
Good Agreement

A mathematical model of a microfluidic controller comprising a hydrogel in a typical T- and Y-junction is derived and presented. The model takes into account conservation of momentum, mass and ions for laminar incompressible flow and the deformation/sensing of a pH-sensitive hydrogel. The response of the pH-responsive hydrogel is validated with experimental equilibrium swelling curves for which good agreement is found. The model is employed to study the behavior of the hydrogel and its impact on the overall fluid flow in different microfluidic flow channel/hydrogel configurations, e.g. in a T-junction, where the hydrogel can act autonomously and without external power supply to regulate the flow. Finally, we discuss how the model can be generalized for other types of stimuli-responsive hydrogels.

scholarly journals Equilibrium swelling of thermo-responsive copolymer microgels

RSC Advances ◽  
2020 ◽  
Vol 10 (70) ◽  
pp. 42718-42732
Author(s):  
A. D. Drozdov ◽  
J. deClaville Christiansen
Keyword(s):  
Phase Transition ◽  
Transition Temperature ◽  
Phase Transition Temperature ◽  
Molar Fraction ◽  
Volume Phase Transition ◽  
Volume Phase ◽  
Volume Phase Transition Temperature ◽  
Equilibrium Swelling ◽  
Copolymer Gels ◽  
Copolymer Microgels

A model is developed for equilibrium swelling of thermo-responsive copolymer gels and is applied to predict the effect of molar fraction of comonomers on the volume phase transition temperature of macroscopic gels and microgels.

scholarly journals Equilibrium Swelling of Biocompatible Thermo-Responsive Copolymer Gels

Gels ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 40
Author(s):  
Aleksey D. Drozdov
Keyword(s):  
Biomedical Applications ◽  
Hydrophobic Interactions ◽  
Volume Phase Transition ◽  
Biotechnological Applications ◽  
Vinyl Methyl ◽  
Potential Toxicity ◽  
Swelling Properties ◽  
Vinyl Methyl Ether ◽  
Equilibrium Swelling ◽  
Copolymer Gels

Biomedical applications of thermo-responsive (TR) hydrogels require these materials to be biocompatible, non-cytotoxic, and non-immunogenic. Due to serious concerns regarding potential toxicity of poly(N-isopropylacrylamide) (PNIPAm), design of alternative homo- and copolymer gels with controllable swelling properties has recently become a hot topic. This study focuses on equilibrium swelling of five potential candidates to replace PNIPAm in biomedical and biotechnological applications: poly(N-vinylcaprolactam), poly(vinyl methyl ether), poly(N,N-dimethyl amino ethyl methacrylate), and two families of poly(2-oxazoline)s, and poly(oligo(ethylene glycol) methacrylates). To evaluate their water uptake properties and to compare them with those of substituted acrylamide gels, a unified model is developed for equilibrium swelling of TR copolymer gels with various types of swelling diagrams. Depending on the strength of hydrophobic interactions (high, intermediate, and low), the (co)polymers under consideration are split into three groups that reveal different responses at and above the volume phase transition temperature.

Amino-functional polyethers: versatile, stimuli-responsive polymers

2020 ◽  
Vol 11 (24) ◽  
pp. 3940-3950 ◽  
Author(s):  
Patrick Verkoyen ◽  
Holger Frey
Keyword(s):  
Ring Opening ◽  
Review Article ◽  
Stimuli Responsive ◽  
New Class ◽  
Stimuli Responsive Polymers ◽  
Responsive Polymers

Amino-functional polyethers have emerged as a new class of “smart”, i.e. pH- and thermoresponsive materials. This review article summarizes the synthesis and applications of these materials, obtained from ring-opening of suitable epoxide monomers.

4D printing technology, modern era: A short review

2020 ◽  
pp. 92-111
Author(s):  
Khodadad Mostakim ◽  
Nahid Imtiaz Masuk ◽  
Md. Rakib Hasan ◽  
Md. Shafikul Islam
Keyword(s):  
Smart Materials ◽  
Computer Aided Design ◽  
Short Review ◽  
Stimuli Responsive ◽  
4D Printing ◽  
Space Applications ◽  
Printing Technology ◽  
Practical Applications ◽  
Biomedical Technologies ◽  
Novel Material

The advancement in 3D printing has led to the rapid growth of 4D printing technology. Adding time, as the fourth dimension, this technology ushered the potential of a massive evolution in fields of biomedical technologies, space applications, deployable structures, manufacturing industries, and so forth. This technology performs ingenious design, using smart materials to create advanced forms of the 3-D printed specimen. Improvements in Computer-aided design, additive manufacturing process, and material science engineering have ultimately favored the growth of 4-D printing innovation and revealed an effective method to gather complex 3-D structures. Contrast to all these developments, novel material is still a challenging sector. However, this short review illustrates the basic of 4D printing, summarizes the stimuli responsive materials properties, which have prominent role in the field of 4D technology. In addition, the practical applications are depicted and the potential prospect of this technology is put forward.

Sign in / Sign up

Export Citation Format

Share Document