Effect of distances between three-dimensional network units on crystallization kinetics of vulcanized polysiloxane elastomers

1970 ◽  
Vol 12 (11) ◽  
pp. 2931-2937 ◽  
Author(s):  
V.Yu. Levin ◽  
V.A. Moskalenko ◽  
A.A. Zhdanov ◽  
G.L. Slonimskii ◽  
K.A. Andrianov ◽  
...  
Keyword(s):  
Crystallization Kinetics ◽  
Three Dimensional ◽  
Dimensional Network ◽  
Kinetics Of

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

Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 452 ◽  
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.

The Effect of Acidity Coefficient on Crystallization Behavior of Blast Furnace Slag Fibers

2018 ◽  
Vol 37 (1) ◽  
pp. 33-37
Author(s):  
Tie-Lei Tian ◽  
Yu-Zhu Zhang ◽  
Hong-wei Xing ◽  
Jie Li ◽  
Zun-Qian Zhang
Keyword(s):  
Thermal Stability ◽  
Crystallization Kinetics ◽  
Blast Furnace Slag ◽  
Chemical Structure ◽  
Crystallization Behavior ◽  
Three Dimensional ◽  
Mineral Wool ◽  
Mineral Wool Fiber ◽  
Kinetics Of ◽  
Furnace Slag

AbstractThe chemical structure of mineral wool fiber was investigated by using Fourier Transform Infrared Spectroscopy (FTIR). Next, the glass transition temperature and the crystallization temperature of the fibers were studied. Finally, the crystallization kinetics of fiber was studied. The results show that the chemical bond structure of fibers gets more random with the increase of acidity coefficient. The crystallization phases of the fibers are mainly melilites, and also a few anorthites and diopsides. The growth mechanism of the crystals is three dimensional. The fibers with acidity coefficient of 1.2 exhibit the best thermal stability and is hard to crystallize as it has the maximum aviation energy of crystallization kinetics.

Quantitation of crystallinity in substantially amorphous pharmaceuticals and study of crystallization kinetics by X-ray powder diffractometry

2000 ◽  
Vol 15 (1) ◽  
pp. 2-6 ◽  
Author(s):  
Rahul Surana ◽  
Raj Suryanarayanan
Keyword(s):  
Water Vapor ◽  
Vapor Pressure ◽  
Crystallization Kinetics ◽  
Water Vapor Pressure ◽  
Three Dimensional ◽  
Weight Percent ◽  
X Ray ◽  
Amorphous Pharmaceuticals ◽  
Integrated Intensities ◽  
Kinetics Of

The first object was to develop an X-ray diffractometric method for the detection and quantification of crystalline sucrose when it occurs as a mixture with amorphous sucrose. Standards consisting of amorphous sucrose physically mixed with 1 to 5 weight percent crystalline sucrose were prepared. The sum of the background subtracted integrated intensities of the 12.7°2θ (6.94 Å) and 13.1°2θ (6.73 Å) sucrose diffraction peaks were linearly related to the weight percent crystalline sucrose. The limits of detection and quantitation of crystalline sucrose were 0.9% and 1.8% w/w, respectively. The second object was to study the kinetics of crystallization of sucrose as a function of temperature (at 102, 105 and 110 °C under a water vapor pressure of 0 Torr) and water vapor pressure (17.4, 19.8 and 21.4 Torr at 27 °C). In all cases, the crystallization kinetics was best described by the Avrami-Erofe’ev model (three-dimensional nucleation).

Nonisothermal Crystallization Kinetics of Poly(m-xylylene adipamide)

2014 ◽  
Vol 971-973 ◽  
pp. 103-106
Author(s):  
Xiao Hua Gu ◽  
Peng Zeng ◽  
Xi Wei Zhang ◽  
Xue Song
Keyword(s):  
Differential Scanning Calorimetry ◽  
Crystallization Kinetics ◽  
Three Dimensional ◽  
Avrami Exponent ◽  
Scanning Calorimetry ◽  
Nonisothermal Crystallization ◽  
Thermal Nucleation ◽  
Nonisothermal Crystallization Kinetics ◽  
Kinetics Of ◽  
Dimensional Crystal

Abstract.In this paper, the nonisothermal crystallization kinetics was investigated by differential scanning calorimetry for the poly(m-xylylene adipamide) (MXD6) which were prepared by polymerization in reactor. The Avrami theory modified by Jeziorny and Z.S. Mo equation were used to describe the nonisothermal crystallization kinetics. The analysis based on the Avrami theory modified by Jeziorny shows that the Avrami exponent n of MXD6 ranges from 2.3 to 3.3, Moreover, both Avrami exponent (n) were around 3.0, which probably suggests a thermal nucleation and a three-dimensional crystal growth. The good linearity of the plots indicates the successful application of Z.S. Mo method in this case.

Non-isothermal crystallization kinetics of isotactic polypropylene nucleated with nucleating agent bicyclic [2,2,1] heptane di-carboxylate

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Yue-fei Zhang ◽  
Xun Li ◽  
Xian-shan Wei
Keyword(s):  
Crystallization Kinetics ◽  
Isotactic Polypropylene ◽  
Growth Pattern ◽  
Isothermal Crystallization ◽  
Three Dimensional ◽  
Nucleating Agent ◽  
Isothermal Crystallization Kinetics ◽  
Spontaneous Nucleation ◽  
Spherulite Growth ◽  
Kinetics Of

AbstractBicyclic [2,2,1] heptane di-carboxylate (commercial product name: HPN- 68) is a novel nucleating agent with high nucleation efficiency for isotactic polypropylene (iPP). In this paper, the non-isothermal crystallization kinetics of virgin iPP and iPP nucleated with HPN-68 were investigated by means of a differential scanning calorimeter (DSC).The Caze method was used to analyze the non-isothermal crystallization kinetics. The results show that addition of HPN-68 can increase the crystallization peak temperature (Tp) of iPP greatly under the same cooling rate. Under non-isothermal conditions, the addition of HPN-68 changes the spherulite growth pattern of iPP. For virgin iPP, the growth pattern is mainly spontaneous nucleation followed by three-dimensional spherulite growth, while for iPP nucleated with HPN-68, the growth pattern is mainly heterogeneous nucleation followed by three-dimensional spherulite growth.

Investigation of the Swelling and Network Parameters of Epoxy Coatings Containing Polyaniline

2017 ◽  
Vol 44 (7) ◽  
pp. 13-16
Author(s):  
V.G. Kurbatov ◽  
E.A. Indeikin
Keyword(s):  
Molar Volume ◽  
Solubility Parameter ◽  
Epoxy Polymer ◽  
Three Dimensional ◽  
Dielectric Permeability ◽  
Polymer Coatings ◽  
Epoxy Coatings ◽  
Dimensional Network ◽  
Kinetics Of ◽  
Kinetics Of Swelling

The kinetics of swelling of epoxy coatings modified with polyaniline is investigated. The influence of the three-dimensional solubility parameter, the dielectric permeability, and the molar volume of solvent on the swelling of epoxy polymer coatings is shown. The parameters of the three-dimensional network for epoxy coatings modified with polyaniline are calculated.

Study on Crystallization Kinetics of Li2O-Al2O3-TiO2-P2O5 Glass by Non-Isothermal Technique

2012 ◽  
Vol 535-537 ◽  
pp. 1629-1633 ◽  
Author(s):  
Yan Hang Wang ◽  
Kun He ◽  
Cheng Kui Zu ◽  
Jiang Chen
Keyword(s):  
Crystallization Kinetics ◽  
Annealing Temperature ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
Crystallization Peak ◽  
X Ray ◽  
Xrd Techniques ◽  
Kinetics Of ◽  
Dsc Curves ◽  
Crystalline Growth

The crystallization kinetics of Li2O-Al2O3-TiO2-P2O5 (LATP) glass was studied by differential scanning calorimeter (DSC) and X-ray diffraction (XRD) techniques. The results showed that DSC curves of LATP glass have a single glass transition temperature followed by one crystallization peak for β = 5 K/min and two crystallization temperatures Tp1 and Tp2 for β ≥ 10 K/min. The activation energies of crystallization obtained from Kissinger model of the first exothermal peak and the second exothermal peak of LATP glass are 251 kJ/mol and 310 kJ/mol, respectively. The Avrami exponents of the both crystallization peaks are approximately 3, indicating that the three-dimensional crystalline growth during its amorphous to crystalline transformation. LiTi2(PO4)3 and unknown crystalline phases firstly form when the mother glass was annealed at 973 K. With increasing of annealing temperature, AlPO4 phase appears.

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