Temperature and frequency-dependent creep and recovery
studies on PVDF-HFP/organo-modified layered double
Vahabodin Goodarzi ,
Hossein Ali Khonakdar ,
Seyed Hassan Jafari,
Gholam hossein Asghari,
Department of Chemical Engineering, Faculty of Engineering, Central Tehran Branch, Islamic Azad University,
P.O. Box 19585-466, Tehran, Iran
Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, P.O. Box 19945-546, Tehran, Iran
Department of Polymer Engineering, Iran Polymer and Petrochemical Institute (IPPI), Tehran 14965115, Iran
Leibniz Institute of Polymer Research, Dresden D-01067, Germany
School of Chemical Engineering, College of Engineering, University of Tehran, P.O. Box 1115-4563, Tehran, Iran
Correspondence to: V. Goodarzi (E-mail: email@example.com or firstname.lastname@example.org)
A series of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) loaded with various contents of layered double
hydroxides (LDHs) nanoparticles were prepared via a melt mixing method. Detailed investigations on LDH dispersion state in the
polymeric matrix conducted by TEM revealed intercalated/exfoliated, and agglomerated structures at low (1 wt %) and high (>3wt
%) loadings of LDH contents, respectively. Wide angle X-ray scattering and DSC results showed that incorporation of LDH into
PVDF-HFP matrix reduced its overall crystallinity and helped to form polar crystallites, while the crystal size at 020 crystallographic
directions was found to be most affected by presence and dispersion state of LDH in the matrix. TGA results showed LDH improved
thermal stability of matrix however, unlike many other nanomaterials it significantly reduced the residual mass which highlights cata-
lytic role of LDH in degradation of residual carbon char. Detailed analysis on creep and recovery data over wide range of selected
temperatures revealed that the creep compliance of nanocomposites are basically controlled by crystallinity and presence of LDH at
low and high temperatures, respectively. Based on obtained storage modulus and creep compliance master curves it was also found
that the influence of LDH on decreasing the creep compliance and improving viscoelastic properties of PVDF-HFP over long time
period and over high frequency ranges becomes more pronounced.
2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46352.
glass transition; mechanical properties; morphology; nanocomposite; structure–property relationships
Received 29 September 2017; accepted 8 January 2018
The piezoelectric materials have attracted attention of inventors
and scientists because of their unique properties not found in
other materials. These materials have a proportional response
toward electrical and/or mechanical loads. They can be classified
under smart materials category.
The piezoelectric polymeric
materials containing fluorine atoms such as poly(vinyldene
fluoride) (PVDF), poly(vinylidene fluoride-co-hexafluoropropy-
lene) (PVDF-HFP), and poly(vinylidene fluoride-co-trifluoro-
ethylene) (PVDF-TrFE) are the most important piezoelectric
polymers which are widely used in many devices.
characteristics of this class of materials stem from fluorine
atoms having a specific arrangement on their chain backbone.
PVDF and PVDF-TrFE are the most famous fluorine containing
piezoelectric materials being widely used in applications such as
ultrasonic motors and pressure sensors and also as ion exchange
membranes in fuel cells.
Pi and coworkers designed a nano-
energy transducer based on PVDF-TrFE.
Pereira and cow-
orkers studied electromechanical behavior of PVDF-TrFE thin
films which prepared with a green solvent via solution casting.
They introduced 1,3-dioxolane (DXL) solvent as replacement
for highly hazardous N,N-dimethylformamide (DMF).
gress of nanotechnology and introduction of new nano-
materials are two key factors for development of novel piezo-
electric materials with improved properties. In this regard,
Nguyen and coworkers studied effect of cluster sizes and surface
modification of ZnO nanoparticles on morphology and
2018 Wiley Periodicals, Inc.
J. APPL. POLYM. SCI. 2018, DOI: 10.1002/APP.46352
46352 (1 of 15)