Triply-responsive OEG-based microgels and hydrogels: Regulation of swelling ratio, volume phase transition temperatures and mechanical properties

2021 ◽  
Author(s):  
Dongdong Lu ◽  
Mingning Zhu ◽  
Jing Jin ◽  
Brian R. Saunders
Keyword(s):  
Phase Transition ◽  
Biomedical Engineering ◽  
Volume Phase Transition ◽  
Swelling Ratio ◽  
Transition Temperatures ◽  
Ph Responsive ◽  
Network Systems ◽  
Volume Phase ◽  
Phase Transition Temperatures ◽  
Volume Swelling

Thermally- and pH-responsive microgels (MGs) and hydrogels are fascinating network systems that have been applied in biomedical engineering and sensing. The volume-swelling ratio (Q) and the volume-phase transition temperatures (VPTTs)...

Fabrication of PVCL-co-PMMA nanofibers with tunable volume phase transition temperatures and maintainable shape for anti-cancer drug release

RSC Advances ◽  
2015 ◽  
Vol 5 (80) ◽  
pp. 64944-64950 ◽  
Author(s):  
Zaiqian Yu ◽  
Hongjuan Gu ◽  
Dongyan Tang ◽  
Haitao Lv ◽  
Yonghui Ren ◽  
...  
Keyword(s):  
Phase Transition ◽  
Controlled Release ◽  
Drug Release ◽  
Anticancer Drugs ◽  
Cancer Drug ◽  
Volume Phase Transition ◽  
Transition Temperatures ◽  
Volume Phase ◽  
Anti Cancer ◽  
Phase Transition Temperatures

Thermo responsive PVCL-co-PMMA nanofibers for controlled release of anticancer drugs were fabricated. The thermo response temperatures of the nanofibers could be easily tuned, and the fibrous shapes could be maintained after heating–cooling cycles.

scholarly journals A robust method to calculate the volume phase transition temperature (VPTT) for hydrogels and hybrids

RSC Advances ◽  
2017 ◽  
Vol 7 (84) ◽  
pp. 53192-53202 ◽  
Author(s):  
Sulalit Bandyopadhyay ◽  
Anuvansh Sharma ◽  
Muhammad Awais Ashfaq Alvi ◽  
Rajesh Raju ◽  
Wilhelm Robert Glomm
Keyword(s):  
Phase Transition ◽  
Transition Temperature ◽  
Phase Transition Temperature ◽  
Volume Phase Transition ◽  
Transition Temperatures ◽  
Robust Method ◽  
Volume Phase ◽  
Volume Phase Transition Temperature ◽  
Phase Transition Temperatures

Phase transition temperatures along with system reversibilities defined by a unique reversibility parameter have been developed in this study.

Controlled Release of Growth Factor Using Poly(N-Isopropyl Acrylamide)Copolymer Hydrogels with Different Volume Phase Transition Temperatures

2005 ◽  
Vol 277-279 ◽  
pp. 77-81
Author(s):  
Young A Han ◽  
Jeong Ok Lim ◽  
Jin Hyun Choi ◽  
Byung Chul Ji
Keyword(s):  
Phase Transition ◽  
Transition Temperature ◽  
Phase Transition Temperature ◽  
Crosslinking Agent ◽  
Volume Phase Transition ◽  
Release Behavior ◽  
Volume Phase ◽  
Volume Phase Transition Temperature ◽  
Isopropyl Acrylamide ◽  
Phase Transition Temperatures

The release behavior of the basic fibroblast growth factor (bFGF) from copolymer hydrogels of N-isopropyl acrylamide (NIPAAm) and sodium methacrylate (SMA) was investigated in relation to the volume phase transition temperatures, which was increased by the incorporation of SMA. In the case of the copolymer hydrogels, a higher volume phase transition temperature was obtained when poly(ethylene glycol) diacrylate (PEGDA) was used as the crosslinking agent, suggesting that the chain length of the crosslinking agent has a significant affect on the volume phase transition temperature of a P(NIPAAm-co-SMA) hydrogel. The concentration of bFGF released from the hydrogels with PEGDA increased relative to the water content, thereby showing a dependence on the volume phase transition temperature. Hence, the release behavior of bFGF from the PNIPAAm and P(NIPAAm-co-SMA) hydrogels was found to be affected by the volume phase transition temperature, which can be easily controlled by changing the comonomer, monomer feed ratio, and crosslinking agent.

scholarly journals Thermal, ferroelastic, and structural properties near phase transitions of organic–inorganic perovskite type [NH3(CH2)3NH3]CdBr4 crystals

RSC Advances ◽  
2021 ◽  
Vol 11 (29) ◽  
pp. 17622-17629
Author(s):  
Ae Ran Lim
Keyword(s):  
Phase Transition ◽  
Phase Transitions ◽  
Thermal Behavior ◽  
Structural Properties ◽  
Structural Dynamics ◽  
Transition Temperatures ◽  
Inorganic Perovskite ◽  
Phase Transition Temperatures ◽  
Perovskite Type

We studied the thermal behavior and structural dynamics of [NH3(CH2)3NH3]CdBr4 near phase transition temperatures.

scholarly journals Accounting for Cooperativity in the Thermotropic Volume Phase Transition of Smart Microgels

Gels ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 42
Author(s):  
Simon Friesen ◽  
Yvonne Hannappel ◽  
Sergej Kakorin ◽  
Thomas Hellweg
Keyword(s):  
Phase Transition ◽  
Interaction Parameter ◽  
Quantitative Description ◽  
Water Molecules ◽  
Volume Phase Transition ◽  
Network Chain ◽  
Solvent Interaction ◽  
Volume Phase ◽  
The Cross ◽  
Interaction Parameter Χ

A full quantitative description of the swelling of smart microgels is still problematic in many cases. The original approach of Flory and Huggins for the monomer–solvent interaction parameter χ cannot be applied to some microgels. The reason for this obviously is that the cross-linking enhances the cooperativity of the volume phase transitions, since all meshes of the network are mechanically coupled. This was ignored in previous approaches, arguing with distinct transition temperatures for different meshes to describe the continuous character of the transition of microgels. Here, we adjust the swelling curves of a series of smart microgels using the Flory–Rehner description, where the polymer–solvent interaction parameter χ is modeled by a Hill-like equation for a cooperative thermotropic transition. This leads to a very good description of all measured microgel swelling curves and yields the physically meaningful Hill parameter ν. A linear decrease of ν is found with increasing concentration of the cross-linker N,N′-methylenebisacrylamide in the microgel particles p(NIPAM), p(NNPAM), and p(NIPMAM). The linearity suggests that the Hill parameter ν corresponds to the number of water molecules per network chain that cooperatively leave the chain at the volume phase transition. Driven by entropy, ν water molecules of the solvate become cooperatively “free” and leave the polymer network.

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