The Melting and Recrystallization Behavior of Poly(ethylene Terephthalate)/SiO2 Nanocomposites Studied by Step-Scan DSC

2009 ◽  
Vol 87-88 ◽  
pp. 69-73
Author(s):  
Chen Liu ◽  
Kang Zheng ◽  
Xia Yin Yao ◽  
Xian Zhang ◽  
Xiang Lan Liu ◽  
...  
Keyword(s):  
Crystallization Temperature ◽  
Isothermal Crystallization ◽  
Ethylene Terephthalate ◽  
Melting Process ◽  
Crystallization Time ◽  
Recrystallization Behavior ◽  
Scanning Calorimetry ◽  
Poly Ethylene Terephthalate ◽  
Sio2 Nanocomposites ◽  
Poly Ethylene

The melting and recrystallization behavior of Poly(ethylene terephthalate) (PET)/SiO2 nanocomposites after isothermal crystallization from the melt was studied by Step-scan differential scanning calorimetry (SDSC). The influence of SiO2 contents, crystallization temperature and crystallization time on the melting process were examined. Two melting endotherms(in the SDSC CP.A curves, reversible part) and one recrystallization exotherm (in the SDSC CP.IsoK curves, irreversible part)of PET/SiO2 nanocomposites after isothermal crystallization were observed during the melt process. This ascribes to the melting-recrystallization mechanism .The low temperature endotherm attributes to the melting of primary crystal formed during the isothermal treating and the high temperature endotherm resulting from the melting of recrystallization materials. The reason why more recrystallization happened with the increase of SiO2 content was given and the process of recrystallization was described in detail. The effects of crystal perfection and recrystallization were minimized by increasing of crystallization temperature and time.

The Melting Behavior of Poly(Ethylene Terephthalate)/ Attapulgite Nanocomposites

2013 ◽  
Vol 773 ◽  
pp. 530-533
Author(s):  
Chen Liu ◽  
Xiang Hui Lu ◽  
Xue Qi ◽  
Peng Li
Keyword(s):  
Crystallization Temperature ◽  
Isothermal Crystallization ◽  
Ethylene Terephthalate ◽  
Melting Process ◽  
Melting Behavior ◽  
Crystallization Time ◽  
Scanning Calorimetry ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Crystallization From The Melt

The melting and recrystallization behavior of Poly(ethylene terephthalate) (PET)/ Attapulgite(At)nanocomposites after isothermal crystallization from the melt was studied by Step-scan differential scanning calorimetry (SDSC). The influence of At contents, crystallization temperature and crystallization time on the melting process were examined. Two melting endotherms(in the SDSC CP.A curves, reversible part) and one recrystallization exotherm (in the SDSC CP.IsoK curves, irreversible part)of PET/At nanocomposites after isothermal crystallization were observed during the melt process. This ascribes to the melting-recrystallization mechanism .The low temperature endotherm attributes to the melting of primary crystal formed during the isothermal treating and the high temperature endotherm resulting from the melting of recrystallization materials. The reason why more recrystallization happened with the increase of At content was given and the process of recrystallization was described in detail. The effects of crystal perfection and recrystallization were minimized by increasing of crystallization temperature and time.

scholarly journals The effect of isothermal crystallization on mechanical properties of poly(ethylene 2,5-furandicarboxylate)

e-Polymers ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 1-11
Author(s):  
Wei Zhang ◽  
Qingyin Wang ◽  
Gongying Wang ◽  
Shaoying Liu
Keyword(s):  
Mechanical Properties ◽  
Intrinsic Viscosity ◽  
Crystallization Temperature ◽  
Isothermal Crystallization ◽  
Tensile Modulus ◽  
Optical Microscope ◽  
Crystallization Time ◽  
Scanning Calorimetry ◽  
Crystallization Properties ◽  
Poly Ethylene

Abstract The effects of isothermal crystallization temperature/time on mechanical properties of bio-based polyester poly(ethylene 2,5-furandicarboxylate) (PEF) were investigated. The intrinsic viscosity, crystallization properties, thermal properties, and microstructure of PEF were characterized using ubbelohde viscometer, X-ray diffraction, polarizing optical microscope, differential scanning calorimetry, and scanning electron microscopy. The PEF sample isothermal crystallized at various temperatures for various times was denoted as PEF-T-t. The results showed that the isothermal crystallization temperature affected the mechanical properties of PEF-T-30 by simultaneously affecting its crystallization properties and intrinsic viscosity. The isothermal crystallization time only affected the crystallization properties of PEF-110-t. The crystallinity of PEF-110-40 was 17.1%. With small crystal size, poor regularity, and α′-crystal, PEF-110-40 can absorb the energy generated in the tensile process to the maximum extent. Therefore, the best mechanical properties can be obtained for PEF-110-40 with the tensile strength of 43.55 MPa, the tensile modulus of 1,296 MPa, and the elongation at a break of 13.36%.

scholarly journals Melting temperature versus crystallinity: new way for identification and analysis of multiple endotherms of poly(ethylene terephthalate)

2020 ◽  
Vol 27 (12) ◽  
Author(s):  
Ferenc Ronkay ◽  
Béla Molnár ◽  
Dóra Nagy ◽  
Györgyi Szarka ◽  
Béla Iván ◽  
...  
Keyword(s):  
Melting Temperature ◽  
Crystallization Temperature ◽  
Ethylene Terephthalate ◽  
Primary Crystallization ◽  
Crystallization Time ◽  
X Ray Diffraction ◽  
Molecular Weights ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Peak Set

AbstractPoly(ethylene terephthalate) (PET) materials with different molecular weights were isothermally crystallized from melt by systematically varying the temperature and duration of the treatment performed in the differential scanning calorimeter (DSC). Multiple endotherm peaks were observed on the subsequent heating thermograms that were separated from each other on the basis of their melting temperature versus crystallization temperature and melting temperature versus crystallinity function. By this new approach five sub-peak sets were identified and then comprehensively characterised. Wide-Angle X-Ray Diffraction (WAXD) analyses revealed that the identified sub-peak sets do not differ in crystalline forms. By analysing the crystallinity and the melting temperature of the sub-peak sets as a function of crystallization time, crystallization temperature and intrinsic viscosity, it was concluded that below the crystallization temperature of 460 K the sub-peak sets that were formed during primary or secondary crystallization transform partially or completely to a third sub-peak set during the heating run of the measurement, while above this temperature, the sub-peak set formed during primary crystallization gradually transforms to a more stable structure, with higher melting temperature. These formations and transformations are described with mathematically defined parameters as well.

scholarly journals Isothermal Crystallization Kinetics of Poly(ethylene terephthalate) Copolymerized with Various Amounts of Isosorbide

2020 ◽  
Vol 10 (3) ◽  
pp. 1046 ◽  
Author(s):  
Nicolas Descamps ◽  
Florian Fernandez ◽  
Pierre Heijboer ◽  
René Saint-Loup ◽  
Nicolas Jacquel
Keyword(s):  
Isothermal Crystallization ◽  
Ethylene Terephthalate ◽  
Systematic Investigation ◽  
Crystallization Time ◽  
Isothermal Crystallization Kinetics ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Half Crystallization Time ◽  
First Time ◽  
Kinetics Of

Poly(ethylene-co-isosorbide terephthalate) (PEIT) copolyesters could be used in various applications depending on their ability to crystallize. Moreover, the possibility to carry out solid-state post-condensation (SSP) is conditioned by its ability to sufficiently crystallize. The present study, thus, gives a systematic investigation of isothermal crystallization of these statistical copolyesters with isosorbide contents ranging from 4.8 to 20.8 mol.%. For each copolyester composition, the lowest isothermal half crystallization times and the highest Avrami constant (K) were obtained around 170 °C. Over the range of composition that was studied, both melting points and melting enthalpies decreased with increasing amounts of isosorbide (from 250 to 207 °C and from 55 to 28 J/g, respectively). On the contrary, half crystallization time displayed an exponential increase when increasing isosorbide contents in the studied range. Finally, structural and thermal analysis of PIT homopolyester are reported for the first time, showing that only ET moieties crystallized when PEIT was subjected to isothermal crystallization at 170 °C.

Nonisothermal Crystallization Kinetics of Poly(ethylene terephthalate) Nanocomposites

2008 ◽  
Vol 8 (4) ◽  
pp. 1812-1822 ◽  
Author(s):  
Jayita Bandyopadhyay ◽  
Suprakas Sinha Ray ◽  
Mosto Bousmina
Keyword(s):  
Crystallization Kinetics ◽  
Isothermal Crystallization ◽  
Ethylene Terephthalate ◽  
Ozawa Method ◽  
Scanning Calorimetry ◽  
Nonisothermal Crystallization ◽  
Poly Ethylene Terephthalate ◽  
Nonisothermal Crystallization Kinetics ◽  
Poly Ethylene ◽  
Kinetics Of

This article reports the nonisothermal crystallization kinetics of poly(ethylene terephthalate) (PET) nanocomposites. The non-isothermal crystallization behaviors of PET and the nanocomposite samples are studied by differential scanning calorimetry (DSC). Various models, namely the Avrami method, the Ozawa method, and the combined Avrami-Ozawa method, are applied to describe the kinetics of the non-isothermal crystallization. The combined Avrami and Ozawa models proposed by Liu and Mo also fit with the experimental data. Different kinetic parameters determined from these models prove that in nanocomposite samples intercalated silicate particles are efficient to start crystallization earlier by nucleation, however, the crystal growth decrease in nanocomposites due to the intercalation of polymer chains in the silicate galleries. Polarized optical microscopy (POM) observations also support the DSCresults. The activation energies for crystallization has been estimated on the basis of three models such as Augis–Bennett, Kissinger and Takhor methods follow the trend PET/2C20A<PET/1.3C20A<PET, indicating incorporation of organoclay enhance the crystallization by offering large surface area.

scholarly journals Molecular Weight and Crystallization Temperature Effects on Poly(ethylene terephthalate) (PET) Homopolymers, an Isothermal Crystallization Analysis

Polymers ◽  
2014 ◽  
Vol 6 (2) ◽  
pp. 583-600 ◽  
Author(s):  
Leonardo Baldenegro-Perez ◽  
Damaso Navarro-Rodriguez ◽  
Francisco Medellin-Rodriguez ◽  
Benjamin Hsiao ◽  
Carlos Avila-Orta ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Crystallization Temperature ◽  
Isothermal Crystallization ◽  
Temperature Effects ◽  
Ethylene Terephthalate ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Poly(ethylene terephthalate)/titanium phosphate nanocomposites: Effect of fillers on thermal, crystallographic diffraction, molecular mobility, and UV-Vis absorption

2019 ◽  
pp. 089270571988692 ◽  
Author(s):  
Gerson Alberto Valencia Albitres ◽  
Sibele Piedade Cestari ◽  
Katharina Rodrigues Malafaia Macedo ◽  
Luis Claudio Mendes ◽  
Mateus Oliveira Cruz ◽  
...  
Keyword(s):  
Molecular Mobility ◽  
Crystallization Temperature ◽  
Ethylene Terephthalate ◽  
Uv Light ◽  
Titanium Phosphate ◽  
Polypropylene Glycol ◽  
Scanning Calorimetry ◽  
Crystallinity Degree ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

There are several chemicals for using as ultraviolet (UV) absorbers. Considering that titanium phosphate (TiP) not yet studied for this purpose, we intended to investigate its effect on poly(ethylene terephthalate) (PET). TiP was synthesized and intercalated with two types of long-chain amine, octadecylamine (OETiP) and ether-amine-O-(2-aminopropyl)-O′-(2-methoxyethyl)polypropylene glycol) (JETiP) being the intercalation assisted by ethylamine. Nanocomposites of PET/TiP (filled with 5 wt%) (PET-TiP, PET-OETiP, and PET-JETiP) were prepared by melting extrusion. Thermogravimetric analysis, differential scanning calorimetry, wide-angle X-ray diffraction (WAXD), Fourier transform infrared spectroscopy, hydrogen low-field nuclear magnetic resonance (1H LFNMR), and UV-visible (Vis) absorption were used for characterizations. OETiP and JETiP induced the decrease of PET glass transition temperature ( T g) and heat crystallization temperature ( T ch) while PET crystallinity degree ( X c), cold crystallization temperature ( T cc), and crystallization rate increased. WAXD suggested the intercalation of PET chains inside of fillers lamellae. According to 1H LFNMR, all fillers increased the PET molecular mobility. Diffuse reflectance revealed increase of the absorption at UV light region. The sample might be thought as a UV absorber.

scholarly journals Comparative Study of Structural Changes of Polylactide and Poly(ethylene terephthalate) in the Presence of Trichoderma viride

2021 ◽  
Vol 22 (7) ◽  
pp. 3491
Author(s):  
Grażyna B. Dąbrowska ◽  
Zuzanna Garstecka ◽  
Ewa Olewnik-Kruszkowska ◽  
Grażyna Szczepańska ◽  
Maciej Ostrowski ◽  
...  
Keyword(s):  
Structural Changes ◽  
Ethylene Terephthalate ◽  
Molecular Mechanisms ◽  
Blot Hybridization ◽  
Trichoderma Viride ◽  
Cost Effective ◽  
Plastic Pollution ◽  
Scanning Calorimetry ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Plastic pollution is one of the crucial global challenges nowadays, and biodegradation is a promising approach to manage plastic waste in an environment-friendly and cost-effective way. In this study we identified the strain of fungus Trichoderma viride GZ1, which was characterized by particularly high pectinolytic activity. Using differential scanning calorimetry, Fourier-transform infrared spectroscopy techniques, and viscosity measurements we showed that three-month incubation of polylactide and polyethylene terephthalate in the presence of the fungus lead to significant changes of the surface of polylactide. Further, to gain insight into molecular mechanisms underneath the biodegradation process, western blot hybridization was used to show that in the presence of poly(ethylene terephthalate) (PET) in laboratory conditions the fungus produced hydrophobin proteins. The mycelium adhered to the plastic surface, which was confirmed by scanning electron microscopy, possibly due to the presence of hydrophobins. Further, using atomic force microscopy we demonstrated for the first time the formation of hydrophobin film on the surface of aliphatic polylactide (PLA) and PET by T. viride GZ1. This is the first stage of research that will be continued under environmental conditions, potentially leading to a practical application.

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