Parameters characterizing the kinetics of the non-isothermal crystallization of polyamide 5,6 determined by differential scanning calorimetry

Abstract The non-isothermal crystallization behavior of polyamide 5,6 (PA56) was investigated by differential scanning calorimeter (DSC), and the non-isothermal crystallization kinetics were analyzed using the modified Avrami equation, the Ozawa model, and the method combining the Avrami and Ozawa equations. It was found that the Avrami method modified by Jeziorny could only describe the primary stage of non-isothermal crystallization kinetics of PA56, the Ozawa model failed to describe the non-isothermal crystallization of PA56, while the combined approach could successfully describe the non-isothermal crystallization process much more effectively. Kinetic parameters, such as the Avrami exponent, kinetic crystallization rate constant, relative degree of crystallinity, the crystallization enthalpy, and activation energy, were also determined for PA56.

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Non-Isothermal Crystallization Kinetics of Graphene Oxide-Carbon Nanotubes Hybrids / Polyamide 6 Composites

Journal of the chemical society of pakistan ◽

10.52568/000760/jcsp/41.03.2019 ◽

2019 ◽

Vol 41 (3) ◽

pp. 394-394

Author(s):

Zhi Qiang Wang Zhi Qiang Wang ◽

Yong Ke Zhao and Xiang Feng Wu Yong Ke Zhao and Xiang Feng Wu

Keyword(s):

Carbon Nanotubes ◽

Graphene Oxide ◽

Cooling Rate ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Crystallization Rate ◽

Polyamide 6 ◽

Degree Of Crystallinity ◽

Isothermal Crystallization Kinetics ◽

Kinetics Of

The hybrids combined by nano-materials with different dimensions usually possess much better enhancement effects than single one. Graphene oxide-carbon nanotubes hybrids / polyamide 6 composites has been fabricated. The non-isothermal crystallization kinetics of the as-prepared samples was discussed. Research results showed that increasing the cooling rate was in favor of increasing the crystallization rate and the degree of crystallinity for the as-prepared samples. Moreover, the crystallization rate was first decreased and then increased with increasing the hybrids loading. Furthermore, the crystallization mechanism was changed with increasing the crystallization temperature and the cooling rate. The nucleation and growth modes of the non-isothermal crystallization could be classified into three different types, according to the Ozawa’s theory. These complicated results could be attributed to the important role of crystallization rate as well as the simultaneous hindering and promoting effects of the as-prepared hybrids. This work has reference values for understanding the crystallization kinetics of the polyamide 6-based composites.

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Thermal Properties and Non-Isothermal Crystallization Kinetics of Poly (δ-Valerolactone) and Poly (δ-Valerolactone)/Titanium Dioxide Nanocomposites

Crystals ◽

10.3390/cryst8120452 ◽

2018 ◽

Vol 8 (12) ◽

pp. 452 ◽

Cited By ~ 3

Author(s):

Waseem Saeed ◽

Abdel-Basit Al-Odayni ◽

Abdulaziz Alghamdi ◽

Ali Alrahlah ◽

Taieb Aouak

Keyword(s):

Titanium Dioxide ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Three Dimensional ◽

Degree Of Crystallinity ◽

Simultaneous Occurrence ◽

Scanning Calorimetry ◽

Isothermal Crystallization Kinetics ◽

The Stability ◽

Kinetics Of

New poly (δ-valerolactone)/titanium dioxide (PDVL/TiO2) nanocomposites with different TiO2 nanoparticle loadings were prepared by the solvent-casting method and characterized by Fourier transform infra-red, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy, and thermogravimetry analyses. The results obtained reveal good dispersion of TiO2 nanoparticles in the polymer matrix and non-formation of new crystalline structures indicating the stability of the crystallinity of TiO2 in the composite. A significant increase in the degree of crystallinity was observed with increasing TiO2 content. The non-isothermal crystallization kinetics of the PDVL/TiO2 system indicate that the crystallization process involves the simultaneous occurrence of two- and three-dimensional spherulitic growths. The thermal degradation analysis of this nanocomposite reveals a significant improvement in the thermal stability with increasing TiO2 loading.

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Effect of Hyperbranched Polymer on Crystallization Kinetics of Isotactic Polypropylene

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.1142 ◽

2012 ◽

Vol 535-537 ◽

pp. 1142-1145

Author(s):

Guang Tian Liu ◽

Jing Lei

Keyword(s):

Activation Energy ◽

Crystallization Kinetics ◽

Isotactic Polypropylene ◽

Isothermal Crystallization ◽

Hyperbranched Polymer ◽

Crystallization Rate ◽

Crystallization Activation Energy ◽

Scanning Calorimetry ◽

Isothermal Crystallization Kinetics ◽

Kinetics Of

In this paper, the isothermal crystallization kinetics of isotactic polypropylene (iPP) and iPP with 5% hyperbranched polymer (HBP) added had been investigated by differential scanning calorimetry (DSC). The results show that a small addition of HBP affects the crystallization behavior of iPP. During isothermal crystallization, the crystallization rate of the blend is higher than those of iPP remarkably. An increase in the Avrami exponent may be attributed to the fractal structure of hyperbranched polymer. The crystallization activation energy is estimated by the Friedman equation, the results show that the activation energy decreases remarkably by addition of HBP and the crystallization rate of the blend is more sensitive to temperature than that of iPP.

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Research in Non-Isothermal Crystallization Kinetics of LDPE Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.848.46 ◽

2013 ◽

Vol 848 ◽

pp. 46-49

Author(s):

Zi Nian Zhao ◽

Xiao Li Lei

Keyword(s):

Differential Scanning Calorimetry ◽

Crystallization Kinetics ◽

Heterogeneous Nucleation ◽

Isothermal Crystallization ◽

Composite System ◽

Crystallization Rate ◽

Scanning Calorimetry ◽

Isothermal Crystallization Kinetics ◽

Inorganic Particles ◽

Kinetics Of

By means of melt blending process in a co-rotating twin screw extruder and blow molding , the low density polyethylene (LDPE)/thermoplastic elastomer(TPE) mixed membranes and LDPE/inorganic particles composite membrane were prepared. by differential scanning calorimetry(DSC) to study the non-isothermal crystallization kinetics of the LDPE composite system by differential scanning calorimetry (DSC).Use modified Jeziorny method to process the data ,the results shows that ZMS, SiO2, EVA and EMAA all play a role of heterogeneous nucleation and the crystallization rate of LDPE has been increased,especially the ZMS/LDPE composite system which heterogeneous nucleation is more obvious and crystallization rate is faster.

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Analysis of the rheological property and crystallization behavior of polylactic acid (Ingeo™ Biopolymer 4032D) at different process temperatures

e-Polymers ◽

10.1515/epoly-2021-0071 ◽

2021 ◽

Vol 21 (1) ◽

pp. 702-709

Author(s):

Hyeong Min Yoo ◽

Su-Yeon Jeong ◽

Sung-Woong Choi

Keyword(s):

Rheological Property ◽

Polylactic Acid ◽

Crystallization Kinetics ◽

Crystallization Behavior ◽

Crystallization Rate ◽

Avrami Equation ◽

Scanning Calorimetry ◽

Isothermal Crystallization Kinetics ◽

Shear Rates ◽

Kinetics Of

Abstract The aim of this study was to determine the rheological property and crystallization behavior of polylactic acid (PLA) with improved heat resistance (Ingeo™ Biopolymer 4032D) through investigation of the melt viscosity and crystallization kinetics of PLA at different process temperatures. The viscosity was measured using a rotational rheometer under conditions of shear rates of 0.01, 0.1, and 1/s. The obtained rheological data show that the viscosity tended to decrease slightly as the shear rate increases and decrease sharply as the temperature increases from 180°C to 210°C. To investigate the effect of the process temperature on the crystallization kinetics and final crystallinity of PLA, thermal analysis using isothermal differential scanning calorimetry (DSC) were also performed. The Avrami equation was successfully applied for the isothermal crystallization kinetics model. From crystallization temperature of 85°C to 120°C, we found that the Ingeo™ Biopolymer 4032D PLA had the fastest crystallization rate (t 1/2: 26.0 min) and the largest crystallinity (47.4%) at 100°C.

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Study on the Isothermal Crystallization Kinetics of Polyvinyl Pyrrolidone/Polyamide 6 Blends

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.1487 ◽

2012 ◽

Vol 557-559 ◽

pp. 1487-1491

Author(s):

Shi Jie Zhang ◽

Yi Wen Tang ◽

Xin Li Yang ◽

Li Hua Cheng

Keyword(s):

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Crystallization Process ◽

Crystallization Rate ◽

Polyamide 6 ◽

Polyvinyl Pyrrolidone ◽

Avrami Equation ◽

Intermolecular Hydrogen Bonds ◽

Isothermal Crystallization Kinetics ◽

Kinetics Of

The Avrami equation was used in the study of the isothermal crystallization kinetics of Polyvinyl pyrrolidone/Polyamide 6 Blends. The addition of PVP can hinder the PA6 crystallization process, increase the crystallization half-time and make the crystallization rate decrease. The molecular entanglements and intermolecular hydrogen bonds between PA6 and PVP chains exert some influence also.

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Isothermal Crystallization Kinetics of Poly(ethylene oxide)/Poly(ethylene glycol)-g-silica Nanocomposites

Polymers ◽

10.3390/polym13040648 ◽

2021 ◽

Vol 13 (4) ◽

pp. 648

Author(s):

Xiangning Wen ◽

Yunlan Su ◽

Shaofan Li ◽

Weilong Ju ◽

Dujin Wang

Keyword(s):

Molecular Weight ◽

Ethylene Oxide ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Crystallization Rate ◽

Poly Ethylene Glycol ◽

Isothermal Crystallization Kinetics ◽

Poly Ethylene Oxide ◽

Poly Ethylene ◽

Kinetics Of

In this work, the crystallization kinetics of poly(ethylene oxide) (PEO) matrix included with poly(ethylene glycol) (PEG) grafted silica (PEG-g-SiO2) nanoparticles and bare SiO2 were systematically investigated by differential scanning calorimetry (DSC) and polarized light optical microscopy (PLOM) method. PEG-g-SiO2 can significantly increase the crystallinity and crystallization temperature of PEO matrix under the non-isothermal crystallization process. Pronounced effects of PEG-g-SiO2 on the crystalline morphology and crystallization rate of PEO were further characterized by employing spherulitic morphological observation and isothermal crystallization kinetics analysis. In contrast to the bare SiO2, PEG-g-SiO2 can be well dispersed in PEO matrix at low P/N (P: Molecular weight of matrix chains, N: Molecular weight of grafted chains), which is a key factor to enhance the primary nucleation rate. In particular, we found that the addition of PEG-g-SiO2 slows the spherulitic growth fronts compared to the neat PEO. It is speculated that the interfacial structure of the grafted PEG plays a key role in the formation of nuclei sites, thus ultimately determines the crystallization behavior of PEO PNCs and enhances the overall crystallization rate of the PEO nanocomposites.

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Non-Isothermal Crystallization Kinetics of Injection Grade PHBV and PHBV/Carbon Nanotubes Nanocomposites Using Isoconversional Method

Journal of Composites Science ◽

10.3390/jcs4020052 ◽

2020 ◽

Vol 4 (2) ◽

pp. 52

Author(s):

Thaís Larissa do Amaral Montanheiro ◽

Beatriz Rossi Canuto de Menezes ◽

Larissa Stieven Montagna ◽

Cesar Augusto Gonçalves Beatrice ◽

Juliano Marini ◽

...

Keyword(s):

Carbon Nanotubes ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Model Fitting ◽

Polarized Light ◽

Isoconversional Method ◽

Degree Of Crystallinity ◽

Gamma Aminobutyric Acid ◽

Scanning Calorimetry ◽

Kinetics Of

Carbon nanotubes (CNT)-reinforced polymeric composites are being studied as promising materials due to their enhanced properties. However, understanding the behavior of polymers during non-isothermal crystallization is important once the degree of crystallinity and crystallization processes are affected when nanoparticles are added to matrices. Usually, crystallization kinetics studies are performed using a model-fitting method, though the isoconversional method allows to obtain the kinetics parameter without assuming a crystallization model. Therefore, in this work, CNTs were oxidized (CNT-Ox) and functionalized with gamma-aminobutyric acid (GABA) (CNT-GB) and incorporated into a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) matrix. The influence of the addition and functionalization of CNT in the crystallization kinetics of PHBV was evaluated using the isoconversional method with differential scanning calorimetry (DSC), and by polarized light optical microscopy (PLOM) and Shore D hardness. The incorporation and functionalization of CNT into PHBV matrix did not change the Šesták and Berggren crystallization model; however, the lowest activation energy was obtained for the composite produced with CNT-GB, suggesting a better dispersion into the PHBV matrix. PLOM and Shore D hardness confirmed the results obtained in the kinetics study, showing the smallest crystallite size for CNT-containing nanocomposites and the highest hardness value for the composite produced with CNT-GB.

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