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A very small amount of aryl amide derivative (TMB-5) was used for nucleating Poly(ethylene 2,6-naphathalate) (PEN) by melt blending. The crystalline temperature, crystallinity, and nucleation efficiency of the composites were increased as a result of the addition of TMB-5. The half-time of crystallization decreased upon the addition of TMB-5 and the work required in folding polymer chains were reduced simultaneously in the polymer mixtures. The crystal size of the PEN/TMB-5 blends became smaller due to the increase of nucleation sites. The TMB-5 had no effect on the PEN crystal type. TMB-5 slightly increased the impact strength of PEN. [ABSTRACT FROM AUTHOR]

In comparison with petroleum-based polyester poly (ethylene terephthalate) (PET), bio-based polyester poly(ethylene 2,5-furandicarboxylate) (PEF) possesses superior physical-mechanical properties and therefore brighter prospect of applications in high gas barrier packaging materials, high performance fibers, engineering plastics, etc. However, PEF has not been commercialized yet because of great challenges in the synthetic technologies of PEF and its key monomer, 2,5-furandicarboxylic acid. At the same time, with the deepening researches on the structure-property relationship of PEF, it is found that there are some inherent shortcomings in PEF property; therefore,modification of PEF is necessary to promote its processing and applications. We review the recent progress in the synthesis, structure-property and modification of PEF, and the developing trend and prospects of PEF-based materials have been discussed. [ABSTRACT FROM AUTHOR]

Poly(ethylene 2,5-furanoate) (PEF) is arousing great interest as a biobased alternative to plastics like poly(ethylene terephthalate) (PET) due to its wide range of potential applications, such as food and beverage packaging, clothing, and in the car industry. In the present study, the hydrolysis of PEF powders of different molecular masses (Mn = 55, Mw = 104 kg/mol and (Mn = 18, Mw = 29 kg/mol) and various particle sizes (180 < d and 180 < d < 425 µm) using cutinase 1 from Thermobifida cellulosilytica (Thc_cut1) was studied. Thereby, the effects of molecular mass, particle size and crystallinity on enzymatic hydrolysis were investigated. The results show that particles with lower molecular mass are hydrolyzed faster than those with higher masses, and that the higher the molecular mass, the lower the influence of the particle size on the hydrolysis. Furthermore, cutinases from Humicola insolens (HiC) and Thc_cut1 were compared with regard to their hydrolytic activity on amorphous PEF films (measured as release of 2,5-furandicarboxylic acid (FDCA) and weight loss) in different reaction media (1 M KPO pH 8, 0.1 M Tris-HCl pH 7) and at different temperatures (50 ˚C and 65 ˚C). A 100% hydrolysis of the PEF films was achieved after only 72 h of incubation with a HiC in 1 M KPO pH 8 at 65 ˚C. Moreover, the hydrolysis reaction was monitored by LC/TOF-MS analysis of the released reaction products and by Scanning Electron Microscopy (SEM) examination of the polymer surfaces. Enzymatic hydrolysis of PEF with Thc_cut1 and HiC has potential for use in surface functionalization and recycling purposes. [ABSTRACT FROM AUTHOR]

The effect of nanocrystalline cellulose dispersion on the nonisothermal crystallization of poly(ethylene 2,5-furandicarboxylate) (PEF) has been investigated by means of solvent casting. The cellulose dispersion plays a significant role on the crystallization temperature, thus dispersive equipments of increasing energies were employed to improve the cellulose particles disaggregation. Therefore, ultra-sonic bath, ultra-sonication, and ultra-turrax were used to disperse cellulose nanocrystals in 1,1,1,3,3,3-hexafluoro-2-propanol. Dissolved separately in the same solvent, PEF was then poured into the cellulose suspension before casting. The cellulose whiskers were inspected by transmission electron microscopy. Differential scanning calorimetry was used to measure the crystallization temperature, while scanning electron microscopy visualized the cellulose dispersion at the fracture surface. After investigation on the interaction of cellulose/PEF via Fourier transform infrared spectroscopy, the thermal stability of the blends was measured by means of thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

The present work focuses on the influence of nucleation processes on the crystallization of bio-based poly(ethylene 2,5-furandicarboxylate) (PEF). Nuclei formation has been studied by means of fast scanning calorimetry (FSC) both when cooling from the melt (nonisothermal conditions) and when annealing at either low- or high-temperatures (isothermal conditions). FSC results show that nucleation on cooling can be prevented by using fast rates allowing to keep the polymer in its amorphous state; whereas cooling at moderate rates results in sample nucleation with a subsequent increase of the crystallization rate. Isothermal pretreatment just above the PEF glass transition temperature ( Tg) results in nuclei formation whose rate decreases when the nucleation temperature approaches PEF Tg. On the other hand, annealing below the PEF melting point allows determination of the sample self-nucleation behavior which occurs in a very narrow temperature range, i.e., between 195 and 198 °C. [ABSTRACT FROM AUTHOR]

Poly(ethylene 2,5-furandicarboxylate) (PEF) is a polyester from ethylene glycol and 2,5-Furandicarboxylic acid which has gained increasing interest due to its excellent properties compared to chemically similar PET. This paper presents an estimation of the crystallization enthalpy, the crystalline and amorphous density and the crystallization kinetics of PEF. Using Avrami and the Hoffman-Lauritzen theory, Hoffman-Lauritzen parameters are proposed that relate crystal growth rate of catalyst-free PEF to temperature and molecular weight. Characteristic is a higher activation energy for chain diffusion (U*) for PEF compared PET, which can be attributed to more restricted chain conformational changes. Finally, the crystallization rate of PEF is shown to be significantly affected by catalyst type. [ABSTRACT FROM AUTHOR]

Poly(ethylene 2,5-furandicarboxylate) (PEF) is an emergent biobased polyester whose chemical structure is analogous to poly(ethylene terephthalate). Pilot-scale PEF is synthesized through the direct esterification process from 2,5-furandicarboxylic acid and bio-ethylene glycol. Wide-angle X-ray diffraction (WAXD) measurements reveal similar crystallinities and unit cell structures for melt-crystallized and glass-crystallized samples. The non-isothermal crystallization of PEF sample is investigated by means of DSC experiments both from the glass and the melt. The temperature dependence of the effective activation energy of the growth rate is obtained from these data, and the results show that the glass and early stage of the melt crystallization share common dynamics. Hoffman-Lauritzen parameters and the temperature at maximum crystallization rate are evaluated. It is found that the melt-crystallization kinetics undergo a transition from regime I to II; however, the crystal growth rate from the melt shows an atypical depression at T < 171 °C compared with the predicted Hoffman-Lauritzen theory. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly(ethylene 2,5-furandicarboxylate- co-ethylene succinate) (PEFS) copolymers of 2,5-furandicarboxylic acid (FDCA) and succinic acid with 11.98-91.32 mol % FDCA composition were synthesized via melt polycondensation in the presence of ethylene glycol using tetrabutyl titanate as a catalyst. PEFSs' molecular weight, thermal properties, and molar composition were determined by Fourier transform infrared spectroscopy, gel permeation chromatography, intrinsic viscosity, 1H NMR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and wide-angle X-ray diffraction (WAXD) measurements. From experimental conditions, we obtained random copolymers with number-average molecular weights exceeding 25,600, determined by GPC and 1H NMR analyses. DSC analysis revealed that PEFS copolymers' melting temperatures differed depending on EF units' percentage. TGA studies confirmed that all PEFS copolymers' thermal stability exceeded 300°C. From WAXD analysis, it is observed that the PEFS copolymer crystal structure was similar to that of PES when EF unit was 11.98 mol % and to that of PEF when EF units were 74.35 and 91.32 mol %. These results benefit this novel biodegradable copolymer to be used as a potential biomaterial. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1415-1420, 2013 [ABSTRACT FROM AUTHOR]

Abstract: The glass-transition temperature and non-isothermal crystallization of poly(trimethylene terephthalate)/poly(ethylene 2,6-naphthalate) (PTT/PEN) blends were investigated by using differential scanning calorimeter (DSC). The results suggested that the binary blends showed different crystallization and melting behaviors due to their different component of PTT and PEN. All of the samples exhibited a single glass-transition temperature, indicating that the component PTT and PEN were miscible in amorphous phase. The value of T g predicted well by Gordon–Taylor equation decreased gradually with increasing of PTT content. The commonly used Avrami equation modified by Jeziorny, Ozawa theory and the method developed by Mo were used, respectively, to fit the primary stage of non-isothermal crystallization. The kinetic parameters suggested that the PTT content improved the crystallization of PEN in the binary blend. The crystallization growth dimension, crystallization rate and the degree of crystallinity of the blends were increased with the increasing content of PTT. The effective activation energy calculated by the advanced iso-conversional method developed by Vyazovkin also concluded that the value of E a depended not only on the system but also on temperature, that is, the binary blend with more PTT component had higher crystallization ability and the crystallization ability is increased with increasing temperature. The kinetic parameters U * and K g were also determined, respectively, by the Hoffman–Lauritzen theory. [Copyright &y& Elsevier]

Abstract: Crystal orientation of poly(ethylene 2, 6-naphthalate) (PEN) ultrathin films was investigated by the combination of reflection–absorption infrared spectroscopy (RAIR) and grazing incidence X-ray diffraction (GIXD) techniques. It is concluded that the main-chain of PEN molecule in ultrathin film is prone to alignment parallel to the substrate when compared with thicker films. During the formation of α form crystalline, the naphthalene ring, the Cn molecular chain of PEN as well as the b axis in crystalline tend to take orientation more parallel to the substrate due to the surface-induced effect. However, such an anisotropic structure could not be observed in the bulk PEN. [Copyright &y& Elsevier]

Front Cover: Poly(ethylene 2,5‐furandicarboxylate) (PEF), an emergent biobased polyester, is produced through direct esterification and polycondensation of purified 2,5‐furan‐dicarboxylic acid (FDCA), obtained from sugar derived from 1st or 2nd generation feedstocks. In‐depth understanding and control over the crystallization process from the melt, as well as from the glass, are of major importance from both the academic standpoint and with regard to obtaining final manufactured products, such as bottles or T‐shirts, with desired properties, since fast crystallization from the glassy state is desired for solid‐state polycondensation (SSP) and industrial reprocessing, whereas slow crystallization from the melt is desired for injection stretch blow molding of preforms for bottle blowing. Further details can be found in the article by A. Codou, N. Guigo, J. van Berke, E. de Jong, and N. Sbirrazzuoli* on page 2065. [ABSTRACT FROM AUTHOR]