Surface Nucleation of Dispersed Polyethylene Droplets in Immiscible Blends Revealed by Polypropylene Matrix Self-Nucleation

2021 ◽  
Vol 54 (19) ◽  
pp. 9100-9112
Author(s):  
Enrico Carmeli ◽  
Seif Eddine Fenni ◽  
Maria Rosaria Caputo ◽  
Alejandro J. Müller ◽  
Davide Tranchida ◽  
...  
Keyword(s):  
Immiscible Blends ◽  
Surface Nucleation ◽  
Polypropylene Matrix

scholarly journals Reduction Mechanism of Fine Hematite Ore Particles in Suspension

2021 ◽  
Author(s):  
Zhiyuan Chen ◽  
Christiaan Zeilstra ◽  
Jan van der Stel ◽  
Jilt Sietsma ◽  
Yongxiang Yang
Keyword(s):  
Particle Size ◽  
Temperature Drop ◽  
Reduction Rate ◽  
Reduction Process ◽  
Reciprocal Relationship ◽  
Drop Tube ◽  
Surface Nucleation ◽  
Order Of Magnitude ◽  
Relationship Of ◽  
Kinetics Of

AbstractIn order to understand the pre-reduction behaviour of fine hematite particles in the HIsarna process, change of morphology, phase and crystallography during the reduction were investigated in the high temperature drop tube furnace. Polycrystalline magnetite shell formed within 200 ms during the reduction. The grain size of the magnetite is in the order of magnitude of 10 µm. Lath magnetite was observed in the partly reduced samples. The grain boundary of magnetite was reduced to molten FeO firstly, and then the particle turned to be a droplet. The Johnson-Mehl-Avrami-Kolmogorov model is proposed to describe the kinetics of the reduction process. Both bulk and surface nucleation occurred during the reduction, which leads to the effect of size on the reduction rate in the nucleation and growth process. As a result, the reduction rate constant of hematite particles increases with the increasing particle size until 85 µm. It then decreases with a reciprocal relationship of the particle size above 85 µm.

Nonclassical Surface Nucleation of 6CB at the Air–Liquid Interface of a 6CB Oil-in-Water Nanoemulsion

Langmuir ◽  
2021 ◽  
Author(s):  
Jin Tae Park ◽  
Govind Paneru ◽  
Masao Iwamatsu ◽  
Bruce M. Law ◽  
Hyuk Kyu Pak
Keyword(s):  
Liquid Interface ◽  
Surface Nucleation ◽  
Oil In Water ◽  
Air Liquid Interface

Preparation, Characterization and Processing of PCL/PHO Blends by 3D Bioplotting

2020 ◽  
Vol 35 (5) ◽  
pp. 458-470
Author(s):  
S. Gopi ◽  
B. A. Ramsay ◽  
J. A. Ramsay ◽  
M. Kontopoulou
Keyword(s):  
Viscoelastic Properties ◽  
Biomedical Applications ◽  
Synergistic Effects ◽  
Thermal And Mechanical Properties ◽  
Flow Properties ◽  
Immiscible Blends ◽  
Melt Compounding ◽  
Linear Viscoelastic ◽  
Matrix Morphology ◽  
Good Flow

Abstract Blends of polycaprolactone (PCL) and poly(3-hydroxyoctanoate) P(3HO) were prepared by melt compounding. These immiscible blends exhibited droplet-matrix morphology at compositions up to 30 wt% P(3HO). Even though the addition of amorphous P(3HO) decreased the crystallinity of PCL, the crystallization temperature of the blends increased by 6 to 7 8C. Blends containing up to 30 wt% P(3HO) had higher crystallization rates, and lower crystallization half-times compared to neat PCL. The viscosity of PCL decreased upon addition of P(3HO), making the blends suitable for processing using a 3D bioplotter. Compositions with 10 to 30 wt% P(3HO) were ideal for processing, because of their improved crystallization kinetics, reduced stickiness and good flow properties. Estimation of the interfacial tension by fitting the Palierne model to the linear viscoelastic properties of the blends revealed good compatibility, which gave rise to synergistic effects in the thermal and mechanical properties. The fibres prepared by 3D bioplotting maintained droplet matrix morphology, with finer particle size than the original compounded material. In addition to favourable viscosity and thermal properties, the extruded fibres containing 30 wt% P(3HO) had comparable modulus to the neat PCL, while exhibiting good ductility. These blends may be suitable alternatives to PCL for biomedical applications, because they provide a range of crystallinities, crystallization rates and viscosities.

The Use of Graft Copolymers to Bind Immiscible Blends

Science ◽  
1994 ◽  
Vol 265 (5175) ◽  
pp. 1072-1074 ◽  
Author(s):  
D. Gersappe ◽  
D. Irvine ◽  
A. C. Balazs ◽  
Y. Liu ◽  
J. Sokolov ◽  
...  
Keyword(s):  
Graft Copolymers ◽  
Immiscible Blends

Volume versus surface nucleation in freezing aerosols

2008 ◽  
Vol 77 (5) ◽  
Author(s):  
Ómar F. Sigurbjörnsson ◽  
Ruth Signorell
Keyword(s):  
Volume Versus ◽  
Surface Nucleation

Ultrafine dispersion of a phosphate nucleating agent in a polypropylene matrix via the microemulsion method

RSC Advances ◽  
2014 ◽  
Vol 4 (23) ◽  
pp. 11931 ◽  
Author(s):  
Min Guo ◽  
Yang Zhang ◽  
Jinqing Li ◽  
Guoyuan Pan ◽  
Hao Yan ◽  
...  
Keyword(s):  
Nucleating Agent ◽  
Microemulsion Method ◽  
Polypropylene Matrix

Molecular Dynamics Studies of Surface Nucleation and Crystal Growth of Si on SiO2 Substrates

2005 ◽  
Vol 899 ◽  
Author(s):  
Byoung-Min Lee ◽  
Hong Koo Baik ◽  
Takahide Kuranaga ◽  
Shinji Munetoh ◽  
Teruaki Motooka
Keyword(s):  
Thin Film ◽  
Molecular Dynamics ◽  
Crystal Growth ◽  
Surface Energy ◽  
Md Simulations ◽  
Lower Surface ◽  
Surface Nucleation ◽  
Lower Surface Energy ◽  
Potential Parameters ◽  
Si Thin Film

AbstractMolecular dynamics (MD) simulations of atomistic processes of nucleation and crystal growth of silicon (Si) on SiO2 substrate have been performed using the Tersoff potential based on a combination of Langevin and Newton equations. A new set of potential parameters was used to calculate the interatomic forces of Si and oxygen (O) atoms. It was found that the (111) plane of the Si nuclei formed at the surface was predominantly parallel to the surface of MD cell. The values surface energy for (100), (110), and (111) planes of Si at 77 K were calculated to be 2.27, 1.52, and 1.20 J/m2, respectively. This result suggests that, the nucleation leads to a preferred (111) orientation in the poly-Si thin film at the surface, driven by the lower surface energy.

Influence of Pressure on the Crystallization in SiO2f/SiO2 Composites

2007 ◽  
Vol 336-338 ◽  
pp. 1236-1238
Author(s):  
Chang Ming Xu ◽  
Shi Wei Wang ◽  
Xiao Xian Huang ◽  
Jing Kun Guo
Keyword(s):  
Phase Composition ◽  
Crystalline Phase ◽  
Hot Pressing ◽  
Crystallization Behavior ◽  
Nucleation Mechanism ◽  
Composition Analysis ◽  
Pressing Pressure ◽  
Surface Nucleation ◽  
Bulk Nucleation ◽  
Phase Composition Analysis

The influence of pressure on the crystallization behavior in SiO2f/SiO2 composites hotpressed at 1350°C was studied. The crystalline phase composition analysis on SiO2f/SiO2 composites revealed that the formation of cristobalite was promoted when the hot-pressing pressure ≤ 12 MPa, however suppressed with higher pressure applied. It can be ascribed to the nucleation mechanism change from surface nucleation to bulk nucleation. Analysis on relative density as well as fracture microstructure of SiO2f/SiO2 composites confirmed the conclusion.

Influence of the CaCO3nanoparticles on the molecular orientation of the polypropylene matrix

2003 ◽  
Vol 88 (4) ◽  
pp. 947-952 ◽  
Author(s):  
D. García-López ◽  
J. C. Merino ◽  
J. M. Pastor
Keyword(s):  
Molecular Orientation ◽  
Polypropylene Matrix
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