Effect of Sodium Benzoate on the Crystallization Behavior of Poly (3-Hydroxybutyrate-Co-4-Hydroxybutyrate)

2014 ◽  
Vol 665 ◽  
pp. 375-378 ◽  
Author(s):  
Xiao Ping Wang ◽  
Wen Feng Li ◽  
Hao Zhang ◽  
De Ming Jia
Keyword(s):  
Activation Energy ◽  
Sodium Benzoate ◽  
Mechanical Performance ◽  
Crystallization Rate ◽  
Melt Crystallization ◽  
Crystalline Morphology ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Biodegradable Poly

Poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB), as the latest generation of biosynthesis and biodegradable Poly (β-hydroxyalkanoate) material, its mechanical performance is greatly improved while its application in industry is confined for the inadequate crystallization properties. The effect of sodium benzoate on P34HB’s crystallization behaviors and nucleation mechanism were investigated through differential scanning calorimetry (DSC) and Angle X-ray diffraction (WAXD). WAXD analysis indicated that the adding of sodium benzoate did not chang the crystalline morphology of P34HB. The analysis of the kinetic parameters including the activation energy (ΔEc) of the non-isothermal melt-crystallization were carried out, which demonstrated that both of the Mo crystallization rate parameter and the Kissinger activation energy value are found to be sharply dropped with the addition of sodium benzoate. Compared to pure P34HB, F(T) on 80 % crystallinity of P34HB with 0.25 phr sodium benzoate fell from 38.79 to 17.89, and ΔEc decreased from-63.1 KJ·mol-1 to-108.8 KJ·mol-1, which indicated that the application of sodium benzoate can obviously improve the crystallization rate of P34HB.

scholarly journals Formation of metal oxide-based hydroxysodalite by alkali-activation of kaolinite

Chemija ◽  
2020 ◽  
Vol 31 (3) ◽  
Author(s):  
Ehab AlShamaileh ◽  
Muayad Esaifan ◽  
Qusay Abu-Afifeh
Keyword(s):  
Activation Energy ◽  
Metal Oxide ◽  
Alkali Activation ◽  
Dsc Analysis ◽  
X Ray Diffraction ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Xrd Study ◽  
Dsc Curves

The formation of metal oxide-based hydroxysodalite by alkali-activation of kaolinite is studied using X-ray diffraction (XRD) study and differential scanning calorimetry (DSC) analysis. Different metal oxides (CoO, MgO, FeO and SiO2) were used to form the metal oxide-based hydroxysodalite. The transformation from kaolinite into hydroxysodalite is confirmed by XRD. In the thermodynamic study, the maximum peak temperatures for DSC curves at various heating rates were used to determine the activation energy (Ea) of the hydroxysodalite formation. With magnesium oxide and cobalt oxide, the formation process was found to be exothermic while it was endothermic with iron oxide.

A New Modifier Prepared and it’s Applied in High-Density Polyethylene/Anhydrite Composites

2011 ◽  
Vol 415-417 ◽  
pp. 390-394
Author(s):  
Shao Hui Wang
Keyword(s):  
High Density Polyethylene ◽  
Bending Strength ◽  
Crystallization Rate ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Powder Particles ◽  
Ft Ir ◽  
Anchoring Group ◽  
The Impact

A new Modifier with Silicon radicals as anchoring group and poly(butyl acrylate) as solvatable chain was synthesized and its effect on the properties of HDPE/Anhydrite composites was investigated in this paper. Fourier transmission infrared spectroscopy (FT-IR) results show that the modifier react on the Anhydrite powder particles surface and the modified Anhydrite powder particles particles. compared with that of HDPE/Anhydrite (filled with same non-modified fraction), The impact strength, tensile strength, bending strength and Young’s modulus of modified HDPE/Anhydrite composites increased about 36.6%, 7.5%, 15.6% and 34% respectively. Based on surface analysis by scanning electron microscope (SEM), the Anhydrite powder particles buried well in HDPE matrix when Anhydrite powder particles was coated with the YB modifier. It was found that Anhydrite powder particles significantly increased the crystallization temperature and crystallization rate of HDPE by differential scanning calorimetry (DSC). At same time, through the X-ray diffraction (XRD) found the addition of the YB modifier modified Anhydrite powder particles can not change the formation of crystal HDPE, but can reduce the crystallite size.

scholarly journals Phase Transition and Melt-Recrystallization Behavior of Poly(Butylene Adipate) Investigated by Simultaneous Measurements of Wide-Angle X-Ray Diffraction (WAXD) and Differential Scanning Calorimetry (DSC)

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 75
Author(s):  
Mengfan Wang ◽  
Weiyu Cao
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Heating Process ◽  
Wide Angle ◽  
Melt Crystallization ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Β Phase ◽  
Simultaneous Measurements

Simultaneous measurements of wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC) were carried out to investigate the phase transition and melting behaviors of poly(butylene adipate) (PBA). Thermal expansion changes along the a and b axes of the β form unit cell are different from each other during the heating process. At the beginning of the β to αH (high-temperature α phase) phase transition, the β phase melts very fast, while the recrystallization of the αH phase is delayed and slowed. With the further increment of the temperature, the melting rate of the β phase slows down, while the recrystallization of the αH phase accelerates. The diffraction peak intensity ratios of the β(020):β(110) and αH(020):αH(110) diffraction peaks during the first heating process have similar value. However, the above value is different from the value of α(020):α(110) during the following melt-crystallization process. This difference comes from the different orientations of the crystal lattices of the α and αH(β) crystals to the substrate plane, which indicates that the αH phase inherits the orientation of the β phase during phase transition and the orientation of αH form crystals is different from the α form crystals that crystallized from the melt.

Plasticizer effect on melt blending of polylactide stereocomplex

e-Polymers ◽  
2017 ◽  
Vol 17 (5) ◽  
pp. 409-416 ◽  
Author(s):  
Yottha Srithep ◽  
Dutchanee Pholharn
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Crystallization Rate ◽  
Wide Angle ◽  
Melt Blending ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Neat Plla ◽  
Internal Mixer

AbstractPoly(l-lactide) (PLLA)/poly(d-lactide) (50/50) with plasticizer contents ranging from 2% to 16% w/w were prepared by melt blending using an internal mixer. Wide-angle X-ray diffraction, Fourier transform infrared spectroscopy and differential scanning calorimetry results confirmed that complete stereocomplex polylactide crystallites without any homocrystallites were produced. Compared to neat PLLA, the melting temperature of the stereocomplex polylactide and its plasticized samples was approximately 55°C higher. Higher plasticizer contents decreased glass transition temperature of the stereocomplex, which implied higher flexibility and enhanced the crystallization rate. However, the plasticizer in the stereocomplex reduced the thermal stability.

Influence of Morphology of Vacuum-Evaporated Oligothiophene Derivative Films on Oganic Photovoltaic Performance

2011 ◽  
Vol 181-182 ◽  
pp. 320-323 ◽  
Author(s):  
Xue Quan Zhao ◽  
Li Guan ◽  
Yi Ping Zhong ◽  
Ping Liu ◽  
Wen Ji Deng
Keyword(s):  
Thin Film ◽  
Differential Scanning Calorimetry ◽  
Electron Transfer ◽  
Photovoltaic Performance ◽  
Organic Photovoltaic ◽  
Organic Thin Film ◽  
Crystalline Morphology ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray

In order to understand the influence of morphology of vacuum-evaporated conjugated organic thin film on organic photovoltaic performance, oligothiophene derivatives, 2,3,4,5-tetrathienylthiophene (X-5T) and 2,5-dithienyl-3,4-di ((2,2') bithiophene-5yl) thiophene (X-7T), were prepared. The thermal behaviour and morphologies of vacuum-deposited X-5T and X-7T films were examined by differential scanning calorimetry (DSC) and x-ray diffraction (XRD). The influence of morphologies of vacuum-evaporated X-5T and X-7T films on organic photovoltaic performance was hen investigated. It was found that vacuum-evaporated oligothiophene derivative films possessing crystalline morphology could be beneficial to improve organic photovoltaic performance of device by promoting forward interfacial electron transfer and transport.

Gelation Crystallization of Poly(L-Lactide) in Solvents of Varying Molecular Size

2007 ◽  
Vol 15 (5) ◽  
pp. 389-393
Author(s):  
Hong Hao ◽  
Guozheng Liang ◽  
Junmin Zhao
Keyword(s):  
Differential Scanning Calorimetry ◽  
Ethylene Glycol ◽  
Crystallization Rate ◽  
Molecular Size ◽  
Large Molecule ◽  
X Ray Diffraction ◽  
Poly Ethylene Glycol ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Poly Ethylene

The crystallization behaviour of poly(L-lactide) (PLLA) samples prepared in large-molecule solvents, such as poly(ethylene glycol) (PEG), was studied by differential scanning calorimetry (DSC) and X-ray diffraction. The results indicate that those samples recovered from large-molecule solvents exhibit higher crystallinity, non-isothermal crystallization temperature and faster crystallization rate than the ones crystallized in a small-molecule solvent. The crystallinity of samples from PLLA/PEG gel is about 73% measured by the DSC. The molar size of the solvent has a large influence on the formation of helical conformations and, thereby on the crystallization rate of PLLA in solution.

scholarly journals Effect of Composition on the Crystallization, Water Absorption, and Biodegradation of Poly(ε-caprolactam-co-ε-caprolactone) Copolymers

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2488
Author(s):  
Yuanyuan Dou ◽  
Xinyu Mu ◽  
Yuting Chen ◽  
Zhenbo Ning ◽  
Zhihua Gan ◽  
...  
Keyword(s):  
Water Absorption ◽  
Crystallization Rate ◽  
Nucleating Agent ◽  
Melting Behavior ◽  
Feed Ratio ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Molar Feed Ratio ◽  
Anionic Copolymerization

Poly(ester amide)s have aroused extensive research interest due to the combination of the degradability of polyester and the higher mechanical properties of polyamide. In this work, a series of poly(ε-caprolactam-co-ε-caprolactone) (P(CLA-co-CLO)) copolymers with different compositions were synthesized by anionic copolymerization. The structure, crystallization behavior, water absorption, and biodegradation behavior of these copolymers were investigated by means of nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and polarized optical micrographs (POM). The results indicated that the composition of P(CLA-co-CLO) copolymers can be adjusted by the molar feed ratio. The PCL blocks decreased the crystallization rate of PA6 blocks but had little effect on the melting behavior of PA6, while the crystallized PA6 acted as a heterogeneous nucleating agent and greatly improved the crystallization rate of PCL. Moreover, the introduction of PCL blocks greatly reduced the water absorption of P(CLA-co-CLO) copolymers and endow them a certain degree of degradability.

Mechanical Alloying Influence on the Sintering of Cu-Fe Compound Powders

2007 ◽  
Vol 353-358 ◽  
pp. 1350-1353 ◽  
Author(s):  
Jin Feng Sun ◽  
Ming Zhi Wang ◽  
Xiao Pu Li ◽  
Zhan Wen He ◽  
Yu Cheng Zhao
Keyword(s):  
Activation Energy ◽  
Mechanical Alloying ◽  
Sintering Temperature ◽  
Sintering Process ◽  
Stored Energy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Structure Strength ◽  
Activation Energy Of Diffusion

In this paper, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and sintering process were used to characterize Cu-Fe compound powders milled for different times. The increment of defects and the change of granularity, grain size and crystal structure were discussed. Mechanical Alloying (MA) influence on the sintering of Cu-Fe compound powders was analyzed. The results showed that, the refinement of the powders and the increment of defects such as interface and dislocation induced the energy storage. The stored energy released in the sintering process, which reduced the activation energy of vacancy and the activation energy of diffusion. So the sintering temperature was reduced and the structure, strength and hardness of specimens were improved.

Preparation and characterization of poly(3-hydroxybutyrate)/ Cloisite25A nanocomposites

e-Polymers ◽  
2013 ◽  
Vol 13 (1) ◽  
Author(s):  
Matko Erceg ◽  
Dražan Jozić
Keyword(s):  
Crystallization Rate ◽  
Nucleating Agent ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Tg Analysis ◽  
Solution Intercalation ◽  
X Ray ◽  
Thermal Stability Of

Abstract Poly(3-hydroxybutyrate)/Cloisite25A (PHB/25A) nanocomposites were prepared by solution-intercalation method. The intercalation of PHB chains between the layers of Cloisite25A was observed by X-ray diffraction (XRD). Differential scanning calorimetry (DSC) and non-isothermal thermogravimetry (TG) analysis were performed to study the thermal properties, crystallization and the thermal degradation of the prepared nanocomposites. DSC analysis indicates that Cloisite25A acts as a nucleating agent and increases the crystallization rate of PHB, but due to intercalation reduces its overall degree of crystallinity. TG analysis shows that addition of Cloisite25A enhances the thermal stability of PHB.

Characteristics and Biodegradation Properties of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate)/Functionalized Graphene (PHBV/FGO) Blends

2016 ◽  
Vol 703 ◽  
pp. 290-294
Author(s):  
Yi Ning Hang ◽  
Kun Yan Wang ◽  
Bin Li
Keyword(s):  
Crystallization Behavior ◽  
Diffraction Peak ◽  
Thermal Barrier ◽  
Functionalized Graphene ◽  
Crystalline Morphology ◽  
X Ray Diffraction ◽  
Nucleation Agent ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Pom Analyses

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/functionalized graphene blends were prepared by solution blend method. The structure, thermal properties, thermal degradation and crystalline morphology were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetry (TG), and polarizing optical microscopy (POM) analyses. Experimental results indicated that FGO increase the intensity of diffraction peak. Small-sized PHBV spherulites were formed. FGO affects the crystallization behavior of PHBV as heterogeneous nucleation agent. FGO acts as an effective thermal barrier due to its large aspect ratio and thereby hinders the degradtion of PHBV.

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