Synthesis and properties of an aluminum nitride/polyimide nanocomposite prepared by a nonaqueous suspension process

1997 ◽  
Vol 12 (5) ◽  
pp. 1274-1286 ◽  
Author(s):  
Xiaohe Chen ◽  
Kenneth E. Gonsalves
Keyword(s):  
Aluminum Nitride ◽  
Polar Solvent ◽  
Amic Acid ◽  
Thermal And Mechanical Properties ◽  
Characteristic Model ◽  
Physicochemical Interactions ◽  
Suspension Process ◽  
Polyimide Nanocomposite ◽  
Model Reactions ◽  
Nanoscale Level

A nanocomposite of a chemically synthesized nanostructured aluminum nitride (AlN) and a polyimide has been studied. Using a nonaqueous polar solvent,N-methylpyrrolidinone (NMP), as the suspension media, the degree of particle agglomeration of AlN was reduced dramatically from micron to nanoscale size. Upon the addition of poly(amic acid) to the AlN/NMP suspension, a further deagglomeration of the particles was observed. The surface physicochemical interactions have been investigated by characteristic model reactions using FTIR spectroscopy. A mechanistic interpretation for the deagglomeration and stabilization behavior is discussed. The formation of the AlN/PI nanocomposite was achieved by the rapid solidification of the precursor suspension followed by compression molding. Such an approach for nanocomposites exhibits better homogeneity with ultrafine fillers and allows a tailorable composition and property at the nanoscale level. Finally, AlN/PI nanocomposites with an increased ceramic loading, up to 65% by volume, were attained and their thermal and mechanical properties, along with the compositional effects, have been investigated.

Rheological behavior of an aluminum nitride nanoparticle suspension in Poly(amic acid)-nmp system

1997 ◽  
Vol 501 ◽  
Author(s):  
Xiaohe Chen ◽  
Kenneth Gonsalves ◽  
R. S. Rounds
Keyword(s):  
Aluminum Nitride ◽  
Viscoelastic Behavior ◽  
Amic Acid ◽  
Polymer Particle ◽  
Particle Interactions ◽  
Nanoparticle Suspension ◽  
Dispersion Process ◽  
Physicochemical Interactions ◽  
Nanoparticle Suspensions ◽  
Fluid Media

ABSTRACTPreliminary rheological characterizations of aluminum nitride (AIN) nanoparticle suspensions in nonaqueous Newtonian fluid media, NMP and NMP/poly(amic acid) solutions, reveal marked differences in viscoelastic behavior, at relatively low dispersed phase volume fractions. Dynamic mechanical and steady shear measurements provide experimental evidence of the effective interparticle and polymer/particle interactions in a dispersion process of nonoxide nanoparticles for ceramic/polymer nanocomposites. The rheological nature of the nanoparticle suspensions corresponds to interparticle physicochemical interactions that have been previously concluded and discussed.

Preparation and Properties of Fluorine-Containing Colorless Polyimide Nanocomposite Films with Organo-Modified Montmorillonites for Potential Flexible Substrate

2008 ◽  
Vol 8 (4) ◽  
pp. 1700-1706 ◽  
Author(s):  
Jin-Ho Park ◽  
Jin-Hoe Kim ◽  
Jin-Woo Park ◽  
Jin-Hae Chang ◽  
Chang-Sik Ha
Keyword(s):  
Flexible Substrate ◽  
Thermomechanical Analysis ◽  
Amic Acid ◽  
Nanocomposite Films ◽  
Organic Modifiers ◽  
X Ray Diffraction ◽  
Modified Montmorillonite ◽  
Transmission Electron ◽  
Ft Ir ◽  
Polyimide Nanocomposite

We prepared transparent polyimide (PI) and organo-modified montmorillonite (OMMT) nanocomposite films from the solution of poly(amic acid) and various amounts (0.5–2 wt%) of OMMT in N,N-dimethylacetamide (DMAc). The Poly(amic acid) was prepared from the reaction of 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and 2,2′-bis (trifluoromethyl)-4,4′-diamino phenyl (TFDB). Dodecylamine (C12-) and dodecyltriphenylphosphonium chloride (C12PPh-Cl–) were used as organic modifiers in OMMT. The PI/OMMT nanocomposite films were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscope (TEM), UV-Vis transmission spectra, thermomechanical analysis (TMA), and rheometric dynamic analysis (RDA). As the OMMT contents is increased, PI/OMMT nanocomposites generally show better properties compared to pristine PI films, although the transparency of the PI/OMMT nanocomposite films is sacrificed slightly. However, it is concluded that these nanocomposite films are good candidates for potential flexible substrates.

Titanium 6/4 Single Lap Shear Adhesive Performance of Polyimide Homopolymers and Poly(Siloxane Imide) Segmented Copolymers

1989 ◽  
Vol 153 ◽  
Author(s):  
T. H. Yoon ◽  
C. A. Arnold ◽  
J. E. McGrath
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
High Performance ◽  
Amic Acid ◽  
Thermal Cyclization ◽  
Thermal And Mechanical Properties ◽  
Space Applications ◽  
Aromatic Polyimides ◽  
Segmented Copolymers ◽  
Lap Shear

Polyimides are attractive candidates for advanced electronic and space applications due to their high performance thermal and mechanical properties. However, the typical intractability and insolubility of polyimides has been a disadvantage. Utilization of the soluble intermediate amic acid can, to some extent, circumvent this problem. However, drawbacks to this approach include the hydrolytic instability of the amic acid and the liberation of water during its subsequent thermal cyclization. Residual stress build-up at the imide-substrate interface may occur due to swelling and drying cycles caused by the loss of water and solvent. In addition, the liberation of volatiles from a polyimide adhesive or coating can lead to the creation of voids which may significantly detract from mechanical properties. Polymeric adhesives must flow in order to provide good wetting of adherend surfaces and consolidation of the bond components. Thus, fully imidized, melt and solution processable, high Tg aromatic polyimides are of great interest.

Structural, thermal and mechanical properties of aluminum nitride ceramics with CeO2 as a sintering aid

2016 ◽  
Vol 42 (10) ◽  
pp. 11519-11524 ◽  
Author(s):  
Hyen-Seok Choi ◽  
Ha-Ni Im ◽  
Yu-Mi Kim ◽  
Archana Chavan ◽  
Sun-Ju Song
Keyword(s):  
Mechanical Properties ◽  
Aluminum Nitride ◽  
Thermal And Mechanical Properties ◽  
Sintering Aid ◽  
Nitride Ceramics

Naphthalene Containing Polyimide Nanocomposites Hybrid with Organo-Modified Montmorillonite

2006 ◽  
Vol 111 ◽  
pp. 43-46
Author(s):  
B.K. Chen ◽  
S.Y. Tsay ◽  
C.P. Chen
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Dielectric Constant ◽  
Amic Acid ◽  
Aggregate Formation ◽  
Thermal And Mechanical Properties ◽  
Modified Montmorillonite ◽  
Thermal Imidization ◽  
Tetracarboxylic Dianhydride ◽  
Acid Precursor

To improve the thermal and mechanical properties of polyimides, a nanocomposite of naphthalene containing polyimide (PI) was hybridized with Montmorillonite (MMT). The PI was synthesized from a diamine, 2,7-bis (4-aminophenoxy) naphthalene and polymerized with a 3,3’,4,4’-benzophenone tetracarboxylic dianhydride via thermal imidization. PI-MMT nanocomposites were then prepared from a DMAc solution of poly(amic acid) precursor and a DMAc dispersion of MMT which were organo-modified with various amount of n-dodecylamine. Characterization results demonstrated that the introduction of a small amount of MMT (up to 5%) led to enhanced thermal stability and mechanical properties of PI. The 5% weight loss temperature in N2 was increased by 46oC in comparison to pristine PI with an organoclay content of 5%. The CTE and dielectric constant were decreased. However, at organoclay contents higher than 5% these properties were reduced because the organoclay was poorly dispersed and resulted in aggregate formation.

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