Primary and secondary crystallization of fast-cooled poly(vinylidene fluoride) studied by Flash DSC, wide-angle X-ray diffraction and Fourier transform infrared spectroscopy

Chen, Yingxin; Shen, Qun; Hu, Wenbing

doi:10.1002/pi.5066

Cited by 19 publications

(19 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the rate was raised further, the peak related to the α form began to involve less and less enthalpy and was transformed into a shoulder at the right temperature side of the β crystallization, i.e., the α crystallization becomes the secondary exotherm. These results agree rather well with those obtained by other groups [ 22 , 23 , 24 , 25 ]. Some differences found can be attributed to the distinct equipment used, self-made versus commercial calorimeter, as well as variations in the weight of the PVDF samples.…”

Section: Resultssupporting

confidence: 93%

“…Both peaks were moved to lower temperatures with an increasing cooling rate, their dependence on rate being smaller for that appearing at low temperatures. The high temperature exotherm was associated with crystallization of the α polymorph, while the peak at low temperature was ascribed to the formation of β crystals, as reported [ 22 , 23 , 24 , 25 ].…”

Section: Resultssupporting

confidence: 67%

“…Moreover, a noticeable decrease in intensity of the α bands was found in the latter because its amount was significantly reduced. The cooling protocol applied here seemed to be more efficient than that used previously [ 24 ], where fast-cooled films were prepared by quenching into liquid nitrogen followed by a slow heating back to room temperature. All of these results are in a perfect agreement with those derived from X-ray diffraction.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Characteristics of the Non-Isothermal and Isothermal Crystallization for the β Polymorph in PVDF by Fast Scanning Calorimetry

Pérez¹,

Angulo²,

Blázquez‐Blázquez³

et al. 2020

Polymers

View full text Add to dashboard Cite

Structuring at very high rates has become one of the current and important topics of interest in polymer science, because this is a common protocol in the processing of films or fibers with industrial applicability. This work presents the study by fast scanning calorimetry, FSC, of poly(vinylidene fluoride), paying special attention to the conditions for obtaining the β phase of this polymer, because it is the one technologically more interesting. The results indicate that this β phase of poly(vinylidene fluoride) is obtained when the sample is isothermally crystallized at temperatures below 60 °C. Under non-isothermal conditions, the β polymorph begins to be observed at rates above 400 °C/s, although a coexistence with the α modification is observed, so that exclusively the β phase is obtained only at rates higher than 3000 °C/s.

show abstract

Section: Resultssupporting

confidence: 93%

Section: Resultssupporting

confidence: 67%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Characteristics of the Non-Isothermal and Isothermal Crystallization for the β Polymorph in PVDF by Fast Scanning Calorimetry

Pérez¹,

Angulo²,

Blázquez‐Blázquez³

et al. 2020

Polymers

View full text Add to dashboard Cite

show abstract

“…The mechanical properties of the material are related to the details of the microstructure: for example, the phase content, degree of crystallinity, and size of the crystalline domains. The morphology, in turn, is affected by the processing conditions in terms of cooling rate, flow, and pressure and it evolves in time depending on the thermo‐mechanical history 7–10 …”

Section: Introductionmentioning

confidence: 99%

Deformation and failure kinetics of polyvinylidene fluoride: Influence of crystallinity

Pini

Drongelen

Remmers

et al. 2021

Journal of Polymer Science

View full text Add to dashboard Cite

The present study investigates the effect of processing conditions on the yield kinetics, such as rate dependence of the yield stress and creep rupture, of polyvinilidene fluoride. Samples were compression molded with cooling rates varying from 100°C/s to 0.5°C/min, or isothermally crystallized at temperatures varying from 20 to 120°C. Deformation kinetics were studied over a wide range of strain rates and temperatures. It is shown that for all conditions the yield response is well represented by the Ree–Eyring model. Moreover, the activation volumes and activation energies are independent from the processing conditions. The effect of processing is fully covered by a simple relationship between the rate factors and the degree of crystallinity. Subsequently, the versatility of this relationship is demonstrated by experimental validation.

show abstract

“…For flash DSC measurements, the polymers can be cooling either rapidly, leaving no time for homogeneous nucleation and crystallization processes, or slow enough to ensure both processes. Therefore, the transformation of crystal structure by flash DSC takes the advantage of a precise control of the processing condition . For instance, fast cooling at 5000 K s −1 induces ferroelectric crystalline phases in P(VDF‐TrFE‐CFE) by cold crystallization when heating back to room temperature, while fast cooling scales down the size of ferroelectric crystal in P(VDF‐TrFE) …”

Section: Introductionmentioning

confidence: 99%

Cooling rate controlled microstructure evolution through flash DSC and enhanced energy density in P(VDF–CTFE) for capacitor application

Chen

Shen

et al. 2017

J Polym Sci B Polym Phys

Self Cite

View full text Add to dashboard Cite

Poly(vinylidene fluoride) (PVDF) based polymers are attracting tremendous interest because of their potential applications in advanced energy storage devices. Fundamental understanding of their crystal structure evolution has been proved elusive due to the nature of rapid crystallization rate. Fortunately, flash differential scanning calorimeter (Flash DSC) with a precise control of cooling rate helps to investigate an understanding of structure–property relationships. For the first time, a bimodal distribution of the crystallization rate of P(VDF‐chlorotrifluoroethylene) (CTFE) in the whole temperature range, and a 3D profile of melting point and enthalpy dependence of annealing temperature and time, which is the corresponding crystal structure evolution and the mechanism of crystal nucleation and growth, are revealed by flash DSC. Based on the above conclusions, fast cooling or annealing at low temperature regulates the crystallization behavior, favors a tiny ferroelectric β‐phases, drastically reduces paraelectric spherulite sizes, and leads to greatly enhanced energy storage capacity, but reduction in discharged efficiency. For instance, compared with other processing methods, P(VDF‐CTFE) quenched by liquid nitrogen achieves the highest discharged energy of 10.6 J cm−3 at the maximum electric field of 270 MV m−1. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1245–1253

show abstract

Primary and secondary crystallization of fast-cooled poly(vinylidene fluoride) studied by Flash DSC, wide-angle X-ray diffraction and Fourier transform infrared spectroscopy

Abstract: Homogeneous crystal nucleation of PVDF on fast cooling yields major alpha‐phase crystallites, but further annealing at low temperatures may generate minor beta‐phase crystallites via heterogeneous crystal nucleation

Cited by 19 publications

References 33 publications

Characteristics of the Non-Isothermal and Isothermal Crystallization for the β Polymorph in PVDF by Fast Scanning Calorimetry

Characteristics of the Non-Isothermal and Isothermal Crystallization for the β Polymorph in PVDF by Fast Scanning Calorimetry

Deformation and failure kinetics of polyvinylidene fluoride: Influence of crystallinity

Cooling rate controlled microstructure evolution through flash DSC and enhanced energy density in P(VDF–CTFE) for capacitor application

Contact Info

Product

Resources

About