Polarized Optical Microscopy Results Research Articles

Low driving-voltage four-armed pentaerythritol and coumarin based compounds as potential materials for LCDs

The electro-optical properties of some four-armed liquid crystalline materials with pentaerytrithol core based on coumarin as mesogenic moiety is investigated. The mesogenic moiety is connected to the core via spacers with various chain lengths differing. The compounds are investigated via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) equiped with a temperature controlled hot-stage. Field-Emission Scanning Electron Microscope (FESEM) and “High-Resolution Transmission Electron Microscope (HRTEM) measurements are exhibited a relatively spherical morphology with particle sizes of 145–174 nm. The electro-optical performance of the materials as thin films coated on indium-tin-oxide (ITO) glass substrates are investigated via applied voltage versus transmittance plots, exhibiting relatively low driving voltage values as low as 2.5–3 V. The ordinary (no) and extraordinary (ne) refractive indexes of the compounds at different temperatures are measured showing a good correspondence with the POM results. In conclusion, the studied materials have exhibited proper physicochemical and electro-optical properties as materials for liquid crystal displays (LCD).

Effect of disubstitution pattern of the terminal alkyl chains on the mesophase of liquid crystals based on lanthanide(III) complexes: A study of the thermal, emission and dielectric behavior

In the present work, new luminescent lanthanide complexes with extended mesomorphic range were prepared by coordination to lanthanide ions (Eu3+, Sm3+ and Tb3+) of the new 4-pyridone based organic ligands (L) with 3,4- (7-n) and 3,5-di(alkyloxy)benzyl (8-n) mesogenic groups and variable length (n = 12 or 14 carbon atoms) onto the benzyl unit. The cumulative results of the elemental analyses as well as the 1H, 13C NMR and IR spectroscopies support the structure of the organic derivatives and their lanthanide complexes [LnL3(NO3)3] (9-n/Ln and 10-n/Ln) described in this work. These complexes show characteristic lanthanide solid state emission, both at room and elevated temperatures corresponding to crystalline, glassy or liquid crystal states. The long range SmA phases displayed by all complexes were supported by a combination of characterization methods, including: differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and variable-temperature powder X-ray diffraction (XRD). This work shows that the number, substitution pattern and length of flexible alkoxy chains are important parameters to control the phase-transition characteristics of the lanthanide complexes. Complexes with 3,4-disubstituted pattern (9-n/Ln) show higher clearing temperatures (nearly 60 °C for Eu3+, 70 °C for Sm3+ and 85 °C for Tb3+ complexes) compared to their counterparts with 3,5-disubstituted pattern (10-n/Ln). Moreover, complexes 9-n/Ln crystallize when cooling their LC phase while complexes 10-n/Ln are stable in glassy state at room temperature as a consequence of the different close interdigitated molecular packing evidenced by XRD measurements. Dielectric spectroscopy was employed to detect the changes of order degree specific to each phases (crystalline, LC or isotropic). The variation of dielectric constant and the electrical conductivity versus temperature shows three transition intervals for selected complexes 10-14/Sm and 10-14/Tb, which delimit the main intervals: 45–60 °C, 90–110 °C; 140–160 °C corresponding to the Cr1-Cr2, Cr2 – SmA and SmA-Iso transitions, and agree very well with the DSC results. The change of characteristic time, obtained by Havriliak-Negami fit function, with temperature also provides a very good correlation with the DSC and POM results.

Dielectric properties dependent on crystalline morphology of PP film for HVDC capacitors application

In this paper, the effects and mechanism of crystalline morphology on dielectric loss and breakdown strength of PP film were studied. The crystalline morphology was modified by adding the β-nucleating agent (β-NA). The crystalline types and crystalline morphologies of samples were analysed by the X-Ray diffraction (XRD) and the polarized optical microscopy (POM), respectively. The current integration, representing the dielectric loss, was investigated using the Q(t) method. The DC conductivity was measured at temperature from 25 to 85 °C. The effects of crystalline morphology on the trap energy level distribution were analysed by the isothermal discharge current (IDC). The DC breakdown strength was tested using a pair of ball-plate electrodes at 85 °C. The results of XRD and POM indicate that the addition of β-NA introduced β-spherulites in PP film and the spherulite size of samples with β-NA are smaller the spherulites size of PP without β-NA. The results of IDC indicate that the special structure of β-spherulites introduced deep trap energy levels. The results of Q(t) and DC conductivity indicate that β-spherulites can effectively suppress the current though samples. Besides, the addition of β-nucleating agent increases the DC breakdown strength at 85 °C.

Selective localization of nanohydroxyapatite in poly(3-hydroxybutyrate)/polycaprolactone blends composites and its effects on crystallization and molecular dynamics

This work deals with the thermodynamic selective localization of hydroxyapatite nanoparticles (Hap) and its effects on crystallization and molecular dynamics in immiscible polyester blend films based on poly(3-hydroxybutyrate) (PHB, 90 wt%) and polycaprolactone (PCL, 10 wt%). Polymer blend composite films were obtained through solution casting method and characterized by contact angle (surface energy measurements), ultraviolet–visible spectroscopy (UV–Vis), elemental mapping, X-ray diffraction (WAXD), differential scanning calorimetry (DSC), polarized optical microscopy (POM) and time domain nuclear magnetic resonance (TD-NMR) techniques. It was found that hydroxyapatite (Hap) is selectively localized in the PHB phase and consequently, nanoparticles strongly influenced the PHB crystallization behavior. DSC and POM results indicated that hydroxyapatite nanoparticles acted as a nucleating agent. However, no significant changes in crystallinity degree were observed by WAXD. Fractionated crystallization behavior was observed for PCL droplets and the increase in the Hap concentration promoted heterogeneous nucleation on the droplets surface due to the nanoparticles close to the interface. Molecular dynamics studies by TD-NMR suggested a disordered Hap nanoparticles distribution inside the polymer matrix, leading to slower dynamics in the semirigid fraction of the sample´s magnetization, typically attributed to restricted polymeric chains close to the particle’s surface.

Nematic Phase Induced from Symmetrical Supramolecular H-Bonded Systems Based on Flexible Acid Core

New symmetrical 1:2 supramolecular H-bonded liquid crystals (SMHBLCs) interactions, A/2Bn, were formed between adipic acid and 4-(4′–pyridylazophenyl) 4″-alkoxybenzoates. Optical and mesomorphic behaviors of the prepared SMHBLC complexes were investigated using differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (XRD). FT-IR spectroscopy was carried out to confirm the H-bond interactions of the prepared complexes via Fermi bands formation. Their photo-physical properties were investigated by UV-spectroscopy and the observed absorbance values were found to be mainly dependent on the length of the terminal alkoxy chain. Mesomorphic behaviour for all A/2Bn complexes revealed that all complexes are dimorphic-exhibiting enantiotropic mesophases with induced nematic phases, except for the long chain terminal complex which exhibits only a monomorphic smectic A phase. In order to investigate the effect of mesogenic core geometry on the mesophase properties, a comparison was established between the mesomeric behaviors of the present complexes and previously reported rigid core acid complexes. Finally, the XRD pattern confirmed the POM and DSC results.

Effects and mechanism of cellulose acetate butyrate on the crystallization of polylactic acid

The effect of cellulose acetate butyrate (CAB) on the crystallization kinetics of polylactic acid (PLA) has been investigated by means of differential scanning calorimetry (DSC), polarized optical microscopy (POM) and scanning electron microscopy (SEM). CAB is essentially immiscible with PLA, as CAB spherical particles with average diameters in the range of 140–185 nm dispersed uniformly in PLA matrix. The incorporation of CAB effectively reduces the crystallization rate of PLA even at a low loading of 0.2 wt%. Moreover, it is particularly interesting to find a critical CAB content (about 5 wt%) which further increase in CAB concentration doesn’t bring significant influence on the PLA crystallization rate. Combined with the results of POM, SEM, DSC and selective dissolving experiment, it is proposed that the coating of CAB on the nuclei which enhanced by the nano-scaled CAB structure could strongly inhibit the nucleation, and thereby reduce the overall crystallization rates of PLA.

Effect of chain segment length on crystallization behaviors of poly(l-lactide-b-ethylene glycol-b-l-lactide) triblock copolymer

The poly(l-lactide-b-ethylene glycol-b-l-lactide) (PLLA-PEG-PLLA) triblock copolymers with different chain segment length are fabricated by ring-opening polymerization. The structure, molecular weight, and crystallization behaviors of the triblock copolymers are characterized by Fourier transform infrared, nuclear magnetic resonance spectroscopy, gel permeation in chromatography, X-ray diffraction, differential scanning calorimetry, and polarizing optical microscopy (POM). The results show that the increase of block length is beneficial to improve its crystallization. In addition, the triblock copolymer exhibits a double crystallization phenomenon. The POM results indicate that PEG and PLLA chains of the copolymer crystallize in their respective crystallization temperature regions. The growth rate of the PLLA spherocrystal decreases and the dendritic spherocrystals appear with increasing the PEG chain length when the PLLA chain of the copolymer is isothermal crystallized at 80°C and PLLA chain length is constant. The growth rate of the PEG spherocrystal decreases and the spherocrystal morphology changes little with increasing PLLA chain length when the PEG chain is isothermal crystallized at 25°C and the length of PEG chain remained unchanged.

Electro-optical, thermal and dielectric properties of ternary mixture of E7/6CB/6BA liquid crystal mixture complex

In this study, a novel liquid crystal mixture complex was designed and synthesized from the nematic liquid crystal mixture E7, hexylcyanobiphenyl (6CB) and hexylbenzoic acid (6BA). The thermal and morphological properties were investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The DSC and POM results show that the liquid crystal complexes exhibit liquid crystalline properties with smectic and nematic phase. While the E7 ratio is 80%, the mixture complex has the widest nematic range and exhibits E7 properties. When the E7 weight ratio is less than 80%, with the formation of hydrogen bonds the number of mesogenic phases increases and the nematic range decreases. The electrical properties of obtained samples were measured by impedance spectroscopy technique. The birefringence and contrast ratio of samples also investigated by the help of light transmittance experiment.

Interfacial cylindrite of poly(lactic acid) induced by pulling a single glass fiber

The shear-induced interfacial crystallization structure and morphology of poly(lactic acid) (PLA) was investigated by pulling a single glass fiber (GF) at different velocities and over different durations at 120 °C. The hierarchical cylindrites with two layers were found when the GF pulling speed or pulling time arrived at a critical value according to the polarized optical microscopy (POM) results. Beyond the critical value, the cylindrite thickness of the inner layer sharply increased and finally reached saturation at 18.5 μm along the radial direction. The POM results were consistent with the value of the shear affected range assessed by the thermomechanical model (Monasse, 1992). The relative degree of crystallinity (A922/A956), based on polarized Fourier transform infrared spectroscopy (FTIR), increased with fiber pulling speed, and then reached a plateau at 1.68, corresponding to the critical speed. The spatial competitiveness at the fiber surface is the main factor responsible for the formation mechanism of the cylindrite, especially the hierarchical cylindrite.

Crystallinity and morphology of barium titanate filled poly(vinylidene fluoride) nanocomposites

ABSTRACTIn this study, crystallization behavior and micromorphology of barium titanate (BaTiO3, or BT) filled poly(vinylidene fluoride) (PVDF) nanocomposites were investigated based on Fourier‐transform infrared spectroscopy (FTIR), polarized optical microscopy (POM), differential scanning calorimetry (DSC), and X‐ray diffractometry (XRD). BT/PVDF nanocomposite films with different concentrations of BT nanoparticles were prepared by solution casting method. The results revealed that the electrical conductivity and Seebeck coefficient of PVDF were improved by the incorporation BT nanoparticles. When 2 wt % of BT was loaded into the PVDF matrix, it mediated the β‐phase crystallization in PVDF. Furthermore, the β‐phase crystals could be transformed into α‐phase after the samples were isothermally crystallized at 155 °C for 20 min. The results of DSC and POM suggest that BT nanoparticles could act as nucleation agents, promoting the crystallization activity of PVDF in a nonisothermal crystallization process. The crystal phase is influential to the electrical properties of PVDF, therefore the findings of this study are useful for the development of new applications based on BT/PVDF nanocomposites, such as high‐performance thermoelectric devices or systems. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46877.

An In situ Study on the Orderly Crystal Growth of Pluronic F127 Block Copolymer Blended with and without Ionic Liquid during Isothermal Crystallization

Isothermal crystallization behavior of Pluronic F127 blended with and without an ionic liquid (IL) was investigated by in situ polarized optical microscopy (POM) and Fourier transform infrared spectroscopy (FTIR). For the pure F127, the POM and FTIR results showed that the spherulite size and crystallinity of F127 increased with the melting temperature increasing to 60, 80, and 135°C. This could be explained by the flexibility of the polymer chain at high melting temperatures. For the F127 blended with IL, the POM results showed that the morphology of F127 evolved from spherulite to dendritic segregation and fibrous crystal with the increasing IL content. FTIR results indicated that hydrogen bonds were formed between F127 and IL, and the intensity of the hydrogen bonds became strengthened gradually with increasing IL content. The effect of hydrogen bonds on the morphology evolution of F127/IL is discussed.

Nucleation Enhancement in Stereodefective Poly(l-lactide) by Free Volume Expansion Resulting from Low-Temperature Pressure CO₂ Preconditioning.

Nucleation enhancement in a highly stereodefective poly(l-lactide) (PLLA) with an optical purity of 88% by low-temperature pressure (0 and 35 °C under 2 MPa) CO2 preconditioning was investigated using differential scanning calorimetry (DSC), infrared (IR) spectroscopy, polarized optical microscopy (POM) as well as positron annihilation lifetime spectroscopy (PALS). Despite the preconditioning of the melt-quenched films for 2 h, IR results indicated that no trace of mesophase was generated and the samples remained in the glassy state. However, judging from the results of DSC, IR, and POM, when compared to the untreated sample, both the treated ones showed a significantly enhanced crystal nucleation effect, resulting in the corresponding greatly enhanced crystallization kinetics. Moreover, owing to the existence of the retrograde vitrification, the conditions of the previous low-pressure CO2 conditioning affected the nucleation enhancement effect. When compared to the case of 35 °C, the much lower temperature of 0 °C was more effective for nucleation enhancement. The PALS results indicated that the enlarged free volume, which resulted from the CO2 conditioning, largely accounted for the formation of locally ordered structures, providing many more potential nucleation sites for forming critical nuclei and thus the resulting enhanced crystallization kinetics in glassy PLLA. The present results have implications in understanding the nucleation enhancement effect, in particular in stereodefective PLLA systems, which possess extremely low crystallization ability and are thus probably too problematic to be evaluated by conventional methods.

Solvent-free preparation and performance of novel xylitol based solid-solid phase change materials for thermal energy storage

Novel polymeric solid-solid phase change materials (SSPCMs) were prepared through solvent-free bulk polymerization by employing polyethylene glycol (PEG) as phase change functional segments, diphenylmethane diisocyanate (MDI) as coupling agent and xylitol as curing agent. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), polarizing optical microscopy (POM), differential scanning calorimetry (DSC), accelerated thermal cycling testing and thermogravimetric analysis (TG) were conducted to study the chemical structure, crystalline properties, phase change properties, thermal reliability and stability of SSPCMs, respectively. The crosslinked structure gave the obtained SSPCMs solid-solid phase change process. XRD and POM results showed that SSPCMs have the same crystalline structure, lower degree of crystallinity and smaller crystal size with pure PEG. DSC results indicated that SSPCMs are capable of reversible storing and releasing latent heat in the temperature of −10 to 60°C through phase transitions. Thermal cycling tests demonstrated that SSPCMs have good thermal reliability and chemical stability. TG results testified the thermal stability of SSPCM. The obtained SSPCMs exhibited great potential application in the field of thermal energy storage.

Novel thermosetting phase change materials with polycarbonatediol based curing agent as supporting skeleton for thermal energy storage

PEG based thermosetting phase change materials (PCMs) have been frequently employed for thermal energy storage in building and other fields due to the low cost, no toxic, no corrosive, good thermal properties and no leakage in phase change process. In this article, thermosetting PCMs with polyethylene glycol (PEG) as phase change functional chain and polyaryl polymethylene isocyanate terminated polycarbonatediol (PCD) as curing agent were prepared through a facile and solvent-free bulk polyaddition. This preparation strategy can provide novel mean to design and synthesize PEG based thermosetting PCMs with different structure and performances according to the specific requirement. Moreover, the introduction of PCD will further improve the performance of PCMs. The chemical structure, crystalline properties, phase change properties, thermal reliability and stability of prepared PCMs were investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), polarizing optical microscopy (POM), differential scanning calorimetry (DSC), accelerated thermal cycling testing and thermogravimetric analysis (TGA), respectively. FTIR spectra showed that the PEG based thermosetting PCMs were successfully synthesized. XRD and POM results indicated the similar spherulite structure of virgin PEG and prepared PCMs, and the crystallinity and crystal size of PCMs are affected by the introduction of curing agent. Meanwhile, DSC measurements showed that prepared PCMs have good phase change properties. Accelerated thermal cycling and TGA testing proved the excellent thermal reliability and thermal stability of prepared PCMs.

Effect of the nano-hybrid pour point depressants on the cold flow properties of diesel fuel

The nano-hybrid pour point depressants (PPDs) was prepared by organically modified nano-clay covering in polymeric PPDs, namely, polymethyl acrylate (PMA), ethylene vinyl acetate copolymer and poly-α-olefin. The effects of nano-hybrid PPDs on the cold flow properties of diesel fuel were evaluated. The crystal morphology and crystallization behavior of the diesel fuels in low-temperature were also observed by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). The results indicated that the nano-hybrid PPDs always exhibited a better cold filter plugging point, while it had little effect on solidifying point compared to pure PPDs, and PMA hybrid with organically modified nano-clay in mass ratio of 4:1 exerted the best depression effect. Up addition of 0.15wt.% nano-hybrid PMA (4:1) in diesel, the cold filter plugging point and solidifying point were reduced by 16°C and 14°C, respectively. DSC and POM results showed that the nano-hybrid PMA involved heterogeneous nucleation activity. The nano-hybrid PMA modified the crystallization behavior of diesel by transforming the shape of wax crystals and inhibiting the formation of larger crystals, which result in compact, regular, tiny particle-shaped and uniform arrangement wax morphologies.

Investigating the crystallization behavior of poly(lactic acid) using CdSe/ZnS quantum dots as heterogeneous nucleating agents

Abstract Heterogeneous nucleation is a frequently encountered phenomenon in the crystallization of inorganic nanoparticle/polymer systems, and has a great influence on the morphology and properties (such as optical, mechanical and degradable properties) of the nanocomposites. In this study, a solution casting method was adopted to fabricate CdSe–ZnS quantum dots (QDs)/poly(lactic acid) (PLA) nanocomposites films of various QDs concentrations by using chloroform as the solvent. Fourier transform infrared (FT-IR) spectroscopy, polarized optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffractometry (XRD) were used to characterize the crystallization behavior of the nanocomposites films that had been thermally treated differently from the as-cast state. The FT-IR and POM results showed that the nucleation density and the crystallization ability of PLA are greatly enhanced with addition of the QDs in the processes of isothermal crystallization at 403 K. The results of DSC revealed that the glass transition temperature of PLA has no obvious change with the addition of QDs. For the QDs/PLA samples which were isothermally annealed at 403 K for 30 min, the degree of (melt) crystallinity increased with increase of QD concentrations in the PLA matrix. All the results obtained from FT-IR spectroscopy, POM, DSC, and XRD were consistent, suggesting that the CdSe–ZnS QDs can serve as an efficient heterogeneous nucleating agent for the acceleration and enhancement of the melt crystallization of PLA at the optimized condition.

Effect of Cyclohexane on the Phase Behavior of L64/1-Butyl-3-Methylimidazolium Tetrafluoroborate System

The triblock copolymer poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (L64, PEO13PPO30PEO13) in 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) can form lamellar liquid crystalline (Lα). The effect of apolar cyclohexane molecules on the Lα phase was investigated by using polarized optical microscopy (POM) and small-angle x-ray scattering (SAXS). The results of POM and SAXS show that a suitable amount of cyclohexane can contribute to the formation of lamellar liquid crystals, and the ordering of Lα phase is increased. For comparison, the effect of polar water on Lα phase was explored. After adding water, both EO groups and [BF4]– anion can form hydrogen bonds with water molecules, which weakens the electrostatic interactions between L64 and [Bmim][BF4] and therefore the ordering of lamellar structures is destroyed.

Ultrasonic treatment of polyacrylic acid sodium/NaA zeolite hybrid membranes for the pervaporation dehydration of ethanol

ABSTRACTUltrasonics was used to improve the dispersion of NaA zeolite in polyacrylic acid sodium (PAAS) membranes. The effect of ultrasonication time on the dispersion of NaA zeolite in the membranes, the membrane structure, and performance were investigated. The casting solution and resulting membranes were characterized by viscosity measurement, polarizing optical microscopy (POM), scanning electron microscopy, and X‐ray diffraction (XRD). With increasing ultrasonication time, the viscosity of the casting solution decreased as the chain entanglements decreased. The POM and XRD results showed that crystallization occurred in the PAAS membrane after ultrasonic processing. A more homogeneous morphology was obtained due to improvement in the dispersion of zeolite under ultrasonic treatment for 0.5–1.0 h. As a result, the separation performance was enhanced. The water/ethanol separation factor increased from 176.2 to 577.8. However, the relative separation factor decreased when the ultrasonic time exceeded 2.5 h, due to the appearance of a lamellar structure. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3979–3984, 2013

Functionalized 4-phenyl phthalazinone-based polybenzimidazoles for high-temperature PEMFC

A series of novel polybenzimidazoles containing 4-phenyl phthalazinone moieties and functional hydroxyl groups (PPBIOH) were synthesized from 4-(4-(4-(4-carboxyphenoxy)phenyl)-1-oxophthalazin-2(1H)-yl)benzoic acid (CPPBC), 2,5-dyhydroxyterephthalic acid (TPA-OH) and 3,3′-diaminobenzidine (DAB) in polyphosphoric acid (PPA). The resultant polymers showed good solubility in 98% H2SO4 and NMP. The inherent viscosities of the polymers in 98% H2SO4 at 25°C were in the range of 0.33–2.10dL/g, increasing obviously with decreasing hydroxyl content in the main chain. The corresponding acid doped membranes were prepared directly from the polymerization solution by the PPA process. The chemical structures of PPBIOH polymers and membranes were characterized by FT-IR. These membranes showed reasonable doping levels (10.1–12.2mol H3PO4), high proton conductivities (0.10–0.21Scm−1 above 120°C), good mechanical properties (stress of 1.7–2.9MPa and strain of 28.1–68.0%) and high oxidative stability (breaking time in the range of 52–155h). The structures of PPBIOH membranes were analyzed by the Wide-angle X-ray diffraction (WAXD) and polarized optical microscopy (POM). The WAXD and POM results indicate the acid doped PPBIOH membranes exhibit semi-crystalline character, from which the mechanism of proton conduction can be further investigated. The combination performance makes these PPBIOH membranes promising candidates for potential applications in high-temperature proton exchange membrane fuel cells (PEMFCs).

Facile and effective promotion of β crystalline phase in poly(vinylidene fluoride) via the incorporation of imidazolium ionic liquids

AbstractIn this study, a facile and efficient protocol to enhance the β‐phase content of poly(vinylidene fluoride) (PVDF) is developed, in which the effect of room temperature ionic liquids (RTILs), including [1‐butyl‐3‐methylimidazolium (bmim)][PF6], [bmim][BF4], [bmim][FeCl4] and [bmim][Cl], on the crystallization behavior of PVDF is investigated. The resulting PVDF/RTIL hybrids are characterized by Fourier transform infrared (FTIR) spectroscopy, XRD, polarized optical microscopy (POM) and DSC. The FTIR spectroscopy and XRD results show that the fraction of β‐phase, F(β), is significantly enhanced by the incorporation of RTILs, specifically from 49.2% for neat PVDF to 92.6% for hybrid filled with 15 wt% [bmim][PF6]. The analysis of the crystallization behavior based on the DSC tests reveals that the degree of crystallinity increases with incorporation of RTILs, implying that RTILs could act as directing agents to facilitate the crystallization process, which is further evidenced by the POM results. In addition, the non‐isothermal crystallization kinetics of PVDF and PVDF/RTIL composites are investigated by means of DSC and the results indicate that the addition of the RTILs significantly influences the mechanism of nucleation and growth of PVDF crystallites. © 2013 Society of Chemical Industry