Polyimide Thin Films Produced by Direct Solid-State Polymerization of an Amino Anhydride Monomer

2000 ◽  
Vol 33 (26) ◽  
pp. 9477-9479 ◽  
Author(s):  
Timothy P. Bender ◽  
Zhi Yuan Wang
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Solid State Polymerization ◽  
Direct Solid

scholarly journals New Aspects on the Direct Solid State Polycondensation (DSSP) of Aliphatic Nylon Salts: The Case of Hexamethylene Diammonium Dodecanoate

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2625
Author(s):  
Angeliki D. Mytara ◽  
Athanasios D. Porfyris ◽  
Stamatina N. Vouyiouka ◽  
Constantine D. Papaspyrides
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
Critical Parameter ◽  
Critical Parameters ◽  
Reaction Conditions ◽  
Solid State Polymerization ◽  
Salt Crystals ◽  
Direct Solid ◽  
End Group ◽  
Aliphatic Polyamide

The direct solid state polymerization (DSSP) of hexamethylene diammonium dodecanoate (PA 612 salt) was investigated for two different salt grades, fossil-based and bio-based. Aliphatic polyamide salts (such as PA 612 salt) are highly susceptible to solid melt transition (SMT) phenomena, which restrain the industrial application of DSSP. To that end, emphasis was given on reactor design, being the critical parameter influencing byproduct diffusion, amine loss and inherent DSSP kinetics. Experiments took place both at the microscale and the laboratory scale, in which two different reactors were tested in terms of bypassing SMT phenomena. The new reactor designed here proved quite successful in maintaining the solid state during the reaction. Scouting experiments were conducted in order to assess the effect of critical parameters and determine appropriate reaction conditions. Fossil-based PA 612 products proved to have a better end-group imbalance in comparison to bio-based ones, which is critical in terms of achieving high molecular weight. Finally, a real DSSP process was demonstrated, starting from PA 612 salt crystals and ending with PA 612 particles.

TEM studies of solid-state reactions in sputter-deposited Nb/Al multilayer thin films

1996 ◽  
Vol 54 ◽  
pp. 1020-1021
Author(s):  
F. Ma ◽  
S. Vivekanand ◽  
K. Barmak ◽  
C. Michaelsen
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Stoichiometric Composition ◽  
Analytical Electron Microscopy ◽  
Grain Structure ◽  
Solid State Reactions ◽  
Multilayer Thin Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sputter Deposited

Solid state reactions in sputter-deposited Nb/Al multilayer thin films have been studied by transmission and analytical electron microscopy (TEM/AEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The Nb/Al multilayer thin films for TEM studies were sputter-deposited on (1102)sapphire substrates. The periodicity of the films is in the range 10-500 nm. The overall composition of the films are 1/3, 2/1, and 3/1 Nb/Al, corresponding to the stoichiometric composition of the three intermetallic phases in this system.Figure 1 is a TEM micrograph of an as-deposited film with periodicity A = dA1 + dNb = 72 nm, where d's are layer thicknesses. The polycrystalline nature of the Al and Nb layers with their columnar grain structure is evident in the figure. Both Nb and Al layers exhibit crystallographic texture, with the electron diffraction pattern for this film showing stronger diffraction spots in the direction normal to the multilayer. The X-ray diffraction patterns of all films are dominated by the Al(l 11) and Nb(l 10) peaks and show a merging of these two peaks with decreasing periodicity.

scholarly journals Solid State NMR Spectroscopy a Valuable Technique for Structural Insights of Advanced Thin Film Materials: A Review

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1494
Author(s):  
Mustapha El Hariri El Nokab ◽  
Khaled O. Sebakhy
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Solid State ◽  
Solid State Nmr ◽  
Pulse Sequences ◽  
3D Structure ◽  
Spectroscopic Techniques ◽  
Film Research ◽  
Versatile Technique ◽  
Work Done

Solid-state NMR has proven to be a versatile technique for studying the chemical structure, 3D structure and dynamics of all sorts of chemical compounds. In nanotechnology and particularly in thin films, the study of chemical modification, molecular packing, end chain motion, distance determination and solvent-matrix interactions is essential for controlling the final product properties and applications. Despite its atomic-level research capabilities and recent technical advancements, solid-state NMR is still lacking behind other spectroscopic techniques in the field of thin films due to the underestimation of NMR capabilities, availability, great variety of nuclei and pulse sequences, lack of sensitivity for quadrupole nuclei and time-consuming experiments. This article will comprehensively and critically review the work done by solid-state NMR on different types of thin films and the most advanced NMR strategies, which are beyond conventional, and the hardware design used to overcome the technical issues in thin-film research.

Peculiarities of Intermetallic Phase Formation in the Process of a Solid State Reaction in (Al/Cu)n Multilayer Thin Films

JOM ◽  
2021 ◽  
Author(s):  
Evgeny T. Moiseenko ◽  
Sergey M. Zharkov ◽  
Roman R. Altunin ◽  
Oleg V. Belousov ◽  
Leonid A. Solovyov ◽  
...  
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Phase Formation ◽  
Solid State Reaction ◽  
Intermetallic Phase ◽  
Multilayer Thin Films

scholarly journals Phase Evolution and Amorphous Stability upon Solid-State Reaction in Superlattice-Like Ge–Sb–Te Combinatorial Thin Films

2020 ◽  
Vol 2 (12) ◽  
pp. 3880-3888
Author(s):  
Jian Hui ◽  
Qingyun Hu ◽  
Yuxi Luo ◽  
Tianxing Lai ◽  
Zhan Zhang ◽  
...  
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Solid State Reaction ◽  
Phase Evolution

scholarly journals Giant room temperature elastocaloric effect in metal-free thin-film perovskites

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Cheng Li ◽  
Yu Hui Huang ◽  
Jian-Jun Wang ◽  
Bo Wang ◽  
Yong Jun Wu ◽  
...  
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Room Temperature ◽  
Entropy Change ◽  
Stress Change ◽  
Chemical Doping ◽  
Metal Free ◽  
Organic Ferroelectrics ◽  
Potential Applications ◽  
Unit Stress

AbstractSolid-state refrigeration which is environmentally benign has attracted considerable attention. Mechanocaloric (mC) materials, in which the phase transitions can be induced by mechanical stresses, represent one of the most promising types of solid-state caloric materials. Herein, we have developed a thermodynamic phenomenological model and predicted extraordinarily large elastocaloric (eC) strengths for the (111)-oriented metal-free perovskite ferroelectric [MDABCO](NH4)I3 thin-films. The predicted room temperature isothermal eC ΔSeC/Δσ (eC entropy change under unit stress change) and adiabatic eC ΔTeC/Δσ (eC temperature change under unit stress change) for [MDABCO](NH4)I3 are −60.0 J K−1 kg−1 GPa−1 and 17.9 K GPa−1, respectively, which are 20 times higher than the traditional ferroelectric oxides such as BaTiO3 thin films. We have also demonstrated that the eC performance can be improved by reducing the Young’s modulus or enhancing the thermal expansion coefficient (which could be realized through chemical doping, etc.). We expect these discoveries to spur further interest in the potential applications of metal-free organic ferroelectrics materials towards next-generation eC refrigeration devices.

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