Nanomagnetic Poly(vinyl alcohol) Hydrogels

2013 ◽  
Vol 829 ◽  
pp. 539-543 ◽  
Author(s):  
Sima Asa'di ◽  
Masoud Frounchi ◽  
Susan Dadbin

Surface modified magnetic nanoparticles (M-NPs) were synthetized and stabilized in poly (vinyl-alcohol) solution. The solutions with various magnetic nanoparticles contents were gamma-irradiated and magnetic poly (vinyl-alcohol) (M-PVA) hydrogels were synthesized. The magnetic hydrogels and also the un-irradiated magnetic poly (vinyl alcohol) nanocomposite films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR) and mechanical measurement. The M-NPs were uniformly dispersed in the polymer matrix due to a strong interaction between the surface-modified M-NPs and polymer matrix. Physical properties of the M-PVA hydrogels, including gel fraction and equilibrium water content were measured to evaluate the applicability of these hydrogels for biomedical applications. XRD, FTIR and VSM results indicated that there are important changes in crystalline, chemical and magnetic properties of hydrogels, arising from irradiation.

2018 ◽  
Vol 18 (3) ◽  
pp. 383 ◽  
Author(s):  
Fitri Khoerunnisa ◽  
Hendrawan Hendrawan ◽  
Yaya Sonjaya ◽  
Rizki Deli Hasanah

Electrically conductive nanocomposites polymer of poly(vinyl alcohol)/PVA, glutaraldehyde (GA) and multiwalled carbon nanotubes (MWCNT) has been successfully synthesized. The polymer nanocomposites were prepared by mixing PVA, GA (crosslinker), and MWCNT dispersion with an aid of ultrasonic homogenizer at 50 °C. The content of MWCNT, in particular, was varied in order to determine the effect of MWCNT on electrical conductivity of polymer composites. The polymer mixture was casted into a disc to obtain thin film. The electrical conductivity, surface morphology, and mechanical properties of the composites film were investigated by means of four probes method, FTIR spectroscopy, X-ray diffraction, SEM, AFM, and tensile strength measurement, respectively. It was found that the optimum composition of PVA (10%): GA (1%): MWCNT (1%) was 20:20:3 in volume ratio. The addition of MWCNT induced the electrically conductive network on polymer matrix where the electrical conductivity of nanocomposites film significantly increased up to 8.28 x 10-2 S/sq due to reduction of the contact resistance between conductive filler. Additionally, the mechanical strength of nanocomposites polymer were significantly increased as a result of MWCNT addition. Modification of morphological structure of composite film as indicated by FTIR spectra, X-ray diffraction patterns, SEM, and AFM images verified the effective MWCNT filler network in the polymer matrix.


2021 ◽  
Vol 33 (4) ◽  
pp. 762-766
Author(s):  
BHABANI SHANKAR PANDA ◽  
MOHAMMED ANSAR AHEMAD

The present work concerns on the synthesis of silver nanoparticles at 25 ºC using raw fruits extract of Bakul (Mimusops elengi) tree via chemical reduction route development of poly(vinyl alcohol) PVA-silver polymer nanocomposite films. The nanocomposite films were subjected to characterization by UV-visible, FTIR, X-ray diffraction, field emission scanning electron microscope (FESEM) and thermal studies. The UV-visible spectrum shows a characteristic broad absorption band observed near 465 nm suggesting presence of silver nanoparticles in polymer nanocomposites (PNCs) film. The vibrational band shift of –OH group of poly(vinyl alcohol) in the presence of nanoparticle designated the chemical interaction between –OH group of poly(vinyl alcohol) and silver nanoparticles. The FESEM study confirmed that PVA is not only acted as a capping agent, but also a cross-linking agent. X-ray diffraction study shows that the existence of AgNPs in the poly nanocomposite film and nanoaparticles are crystalline in nature. Thermal studies suggest that the enhanced thermal stability is because of the good packing of the polar crystallites in β-PVA composites as compared to the non-polar α-phase of neat poly(vinyl alcohol) (PVA).


2009 ◽  
Vol 610-613 ◽  
pp. 1137-1142 ◽  
Author(s):  
Ling Li Li ◽  
Guang Li ◽  
Jian Ming Jiang ◽  
Yue Wen Guo

Biomineralization on surface-modified poly (ε-caprolactone) (PCL) through an alternate soaking process was investigated. A poly(vinyl alcohol) (PVA)-coating on PCL substrate prepared by repetitive adsorption/ drying in an aqueous PVA solution could accelerate hydroxyapatite (HA) deposition while PVA-PCL soaked in aqueous solutions containing Ca2+ and PO3-4 ions alternately. Fourier transform infrared (FTIR) and X-ray diffraction of the apatite verified the formed hydroxyapatite in these processes exhibited a close resemblance with calcium phosphates (HA, Ca10(PO4)6(OH)2). It was also found that the amount of HA formed increased with both soaking with both soaking cycles and deposition amount of PVA on PCL. This study suggested that simple PVA coating on PCL substrate could serve as a novel way to accelerated HAP formation via alternating soaking.


Coatings ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 744 ◽  
Author(s):  
Jun Li ◽  
Kwang-Pill Lee ◽  
Anantha Iyengar Gopalan

Magnetic nanoparticles (MNPs) are of great interest due to their unique properties, especially in biomedical applications. MNPs can be incorporated into other matrixes to prepare new functional nanomaterials. In this work, we described a facile, one-step strategy for the synthesis of magnetic poly(vinyl alcohol) (mPVA) gels. In the synthesis, nickel nanoparticles and cross-linked mPVA gels were simultaneously formed. Ni nanoparticles (NPs) were also incorporated into a stimuli-responsive polymer to result in multiresponsive gels. The size of and distribution of the Ni particles within the mPVA gels were controlled by experimental conditions. The mPVA gels were characterized by field emission scanning electron microscope, X-ray diffraction, magnetic measurements, and thermogravimetric analysis. The new mPVA gels are expected to have applications in drug delivery and biotechnology.


Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 691
Author(s):  
O. Sánchez-Aguinagalde ◽  
Ainhoa Lejardi ◽  
Emilio Meaurio ◽  
Rebeca Hernández ◽  
Carmen Mijangos ◽  
...  

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.


2021 ◽  
Vol 56 (9) ◽  
pp. 5936-5955
Author(s):  
J. A. Benítez-Martínez ◽  
I. M. Garnica-Palafox ◽  
G. Vázquez-Victorio ◽  
M. Hautefeuille ◽  
F. M. Sánchez-Arévalo

2012 ◽  
Vol 409-410 ◽  
pp. 156-163 ◽  
Author(s):  
Hua-Dong Huang ◽  
Peng-Gang Ren ◽  
Jun Chen ◽  
Wei-Qin Zhang ◽  
Xu Ji ◽  
...  

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