The Constitutive Response of Active Polymer Gels

1999 ◽  
Vol 600 ◽  
Author(s):  
S. P. Marra ◽  
K. T. Ramesh ◽  
A. S. Douglas
Keyword(s):  
Mechanical Properties ◽  
Acrylic Acid ◽  
Vinyl Alcohol ◽  
Polymer Gels ◽  
Mechanical Deformation ◽  
Poly Vinyl Alcohol ◽  
Artificial Muscles ◽  
Ionic Polymer ◽  
Constitutive Response ◽  
Ph Level

AbstractActive polymer gels can achieve large, reversible deformations in response to environmental stimuli, such as the application of an electric field or a change in pH level. Consequently, great interest exists in using these gels as actuators and artificial muscles. The goal of this work is to characterize the mechanical properties of ionic polymer gels and to describe how these properties evolve as the gel actuates. Experimental results of uniaxial tests on poly(vinyl alcohol)-poly(acrylic acid) gels are presented for both acidic and basic environments. These materials are shown to be to be slightly viscoelastic and compressible and capable of large recoverable deformations. The gels also exhibit similar stress in response to mechanical deformation in both the acid and the base.

Study on the Mechanical Characteristics of Ionic Polymer Actuators

2013 ◽  
Vol 448-453 ◽  
pp. 2959-2962
Author(s):  
Xuan Lun Wang ◽  
You Bing Li ◽  
Il Kwon Oh
Keyword(s):  
Mechanical Properties ◽  
Vinyl Alcohol ◽  
Mechanical Characteristics ◽  
Poly Vinyl Alcohol ◽  
Resistance Force ◽  
Ambient Water ◽  
Ionic Polymer ◽  
Polymer Actuators ◽  
Length Increment ◽  
Tip Displacement

Sulfonated endcapped poly (arylenethioethersulfone) copolymer (SPTES) was synthesized through direct copolymerization of sulfonated monomers and poly (vinyl alcohol) (PVA) was crosslinked with SPTES by the dehydration method. The mechanical characteristics of polymer actuators are investigated. Nafion actuators as a comparison were also investigated. The normalized tip displacements were calculated for both PVA/SPTES actuators and Nafion actuators in order to delete the dimensions influence on the bending behaviours. The bending performances were tested under AC excitations with different frequencies. The results showed that the normalized tip displacement decreased with both the width and length of the IPMC strips. That is due to the increase of the monment inetia of the IPMC strips with the increment of the width or the length increment will lead to the larger resistance force from ambient water along with the increase of the area of IPMC strips. PVA/SPTES actuators showed comparable bending performances compared with its Nafion counterparts based on the study of mechanical properties.

Deformation Behavior of Polymer Gels in Electric Field

1989 ◽  
Vol 171 ◽  
Author(s):  
Toshio Kurauchi ◽  
Tohru Shiga ◽  
Yoshiharu Hirose ◽  
Akane Okada
Keyword(s):  
Acrylic Acid ◽  
Electric Field ◽  
Vinyl Alcohol ◽  
Deformation Behavior ◽  
Polymer Gels ◽  
Poly Vinyl Alcohol ◽  
Robot Hand ◽  
Poly Acrylic Acid

ABSTRACTThe deformation of poly(acrylic acid)—co—(acrylamide) gels and poly(vinyl alcohol)—poly(acrylic acid) gels under an electric field was investigated. Bending of these ionic gels was induced by an electic field. Using this deformation, we constructed a prototype of a robot hand having soft fingers, and an artificial fish able to swim.

Synthesis, characterization, and their some chemical and biological properties of PVA/PAA/nPS hydrogel nanocomposites: Hydrogel and wound dressing

2020 ◽  
Vol 35 (3) ◽  
pp. 203-215
Author(s):  
Mehmet Emin Diken ◽  
Berna Koçer Kizilduman ◽  
Begümhan Yilmaz Kardaş ◽  
Enes Emre Doğan ◽  
Mehmet Doğan ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Acrylic Acid ◽  
Infrared Spectra ◽  
Vinyl Alcohol ◽  
Fourier Transform Infrared ◽  
Poly Vinyl Alcohol ◽  
Seed Particles ◽  
Fourier Transform Infrared Spectra ◽  
Hydrogel Nanocomposites ◽  
Poly Acrylic Acid

The nanocomposite hydrogels were prepared by dispersing of the nanopomegranate seed particles into poly(vinyl alcohol)/poly(acrylic acid) blend matrix in an aqueous medium by the solvent casting method. These hydrogels were characterized using scanning electron microscopy, Fourier transform infrared spectra, differential scanning calorimetry, and optical contact angle instruments. The nanopomegranate seed, blend, and hydrogel nanocomposites were tested for microbial activity. In addition, cytocompatibilities of these blend and hydrogel nanocomposites/composites were tested on human lymphocyte with in vitro MTS cell viability assays. Fourier transform infrared spectra revealed that esterification reaction took place among functional groups in the structure of poly(vinyl alcohol) and poly(acrylic acid). The hydrophilic properties of all hydrogels decreased with increasing nanopomegranate seed content. The mean diameters of the nanopomegranate seed particles were about 88 nm. Nanopomegranate seed particles demonstrated antibacterial properties against gram-positive bacteria, Staphylococcus aureus, and gram-negative bacteria, Escherichia coli. The lymphocyte viabilities increased after addition of nanopomegranate seeds into the polymer blend. The swelling behavior of blend and hydrogels was dependent on the cross-linking density created by the reaction between poly(vinyl alcohol)/poly(acrylic acid) blend and nanopomegranate seed. Scanning electron microscopy images were highly consistent with Fourier transform infrared spectra, differential scanning calorimetry, and antibacterial activity results.

scholarly journals Novel Hydrogels of Chitosan and Poly (vinyl alcohol) Reinforced with Inorganic Particles of Bioactive Glass

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 691
Author(s):  
O. Sánchez-Aguinagalde ◽  
Ainhoa Lejardi ◽  
Emilio Meaurio ◽  
Rebeca Hernández ◽  
Carmen Mijangos ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Drug Release ◽  
Bioactive Glass ◽  
Vinyl Alcohol ◽  
Release Kinetics ◽  
The Body ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
Inorganic Particles ◽  
Release Studies

Chitosan (CS) and poly (vinyl alcohol) (PVA) hydrogels, a polymeric system that shows a broad potential in biomedical applications, were developed. Despite the advantages they present, their mechanical properties are insufficient to support the loads that appear on the body. Thus, it was proposed to reinforce these gels with inorganic glass particles (BG) in order to improve mechanical properties and bioactivity and to see how this reinforcement affects levofloxacin drug release kinetics. Scanning electron microscopy (SEM), X-ray diffraction (XRD), swelling tests, rheology and drug release studies characterized the resulting hydrogels. The experimental results verified the bioactivity of these gels, showed an improvement of the mechanical properties and proved that the added bioactive glass does affect the release kinetics.

scholarly journals Fabrication of Hybrid Nanofibers from Biopolymers and Poly (Vinyl Alcohol)/Poly (ε-Caprolactone) for Wound Dressing Applications

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2104
Author(s):  
Sibusiso Alven ◽  
Blessing Atim Aderibigbe
Keyword(s):  
Mechanical Properties ◽  
Wound Healing ◽  
Vinyl Alcohol ◽  
Wound Dressing ◽  
Chronic Wounds ◽  
Cellular Adhesion ◽  
Wound Dressings ◽  
Poly Vinyl Alcohol ◽  
High Porosity ◽  
Hybrid Nanofibers

The management of chronic wounds is challenging. The factors that impede wound healing include malnutrition, diseases (such as diabetes, cancer), and bacterial infection. Most of the presently utilized wound dressing materials suffer from severe limitations, including poor antibacterial and mechanical properties. Wound dressings formulated from the combination of biopolymers and synthetic polymers (i.e., poly (vinyl alcohol) or poly (ε-caprolactone) display interesting properties, including good biocompatibility, improved biodegradation, good mechanical properties and antimicrobial effects, promote tissue regeneration, etc. Formulation of these wound dressings via electrospinning technique is cost-effective, useful for uniform and continuous nanofibers with controllable pore structure, high porosity, excellent swelling capacity, good gaseous exchange, excellent cellular adhesion, and show a good capability to provide moisture and warmth environment for the accelerated wound healing process. Based on the above-mentioned outstanding properties of nanofibers and the unique properties of hybrid wound dressings prepared from poly (vinyl alcohol) and poly (ε-caprolactone), this review reports the in vitro and in vivo outcomes of the reported hybrid nanofibers.

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