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Self-assembly (SA) of amphiphilic block copolymers (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)) was investigated in dispersions of multi-walled carbon nanotubes (MWNT) as a function of temperature using spin probe electron paramagnetic resonance (EPR) spectroscopy. Nitroxidelabeled Pluronic with a short poly(ethylene oxide) block, L62-NO, and a small molecular probe, 4-hydroxy-TEMPO-benzoate, 4HTB, were used for probing the local dynamic and polarity of the polymer chains in the presence of the nanostructures. It was found that MWNT modify the temperature, and the dynamic behavior of polymer SA and comparison between the MWNT and single-walled nanotube (SWNT) showed that the structure and dynamical behavior of the nanostructure-polymer hybrids formed depend on the size matching between the diameter of the native micelles and the additives. While SWNT induced the formation of hybrid polymer-SWNT micelles, MWNT (with a diameter of 20-40 nm) induced the assembly of polymer aggregates at the surface of the MWNT.

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Present technologies allow fabrication of aluminum/diamond particles composites with excellent thermal properties, in particular showing the by far highest Thermal Conductivity of any of the materials being evaluated for thermal management. Although there is a widespread consensus concerning the essential role that the interface plays, it is not yet fully clear how the aluminum carbide formed at the interface affects thermal properties. In particular, how it affects the stability of the thermal properties of composites subjected to thermal treatments under wetting conditions. This is precisely the objective of the present work. To this end, samples were fabricated by means of gas pressure infiltration of liquid Al into preforms of packed diamond particles. Infiltration was carried out at two temperatures and three contact times. Thermal fatigue with cooling phase in water and performance in moisture environments at temperatures close to 100°C were evaluated. The results show that those samples having low amounts of carbide at the interface (shorter contact times) are more prone to a decrease of the thermal conductivity.

Please cite this article as: Monje, I.E., Louis, E., Molina, J.M., On critical aspects of infiltrated Al/diamond composites for thermal management: Diamond quality vs processing conditions, Composites: Part A (2014), doi: http://dx.doi.org/10. 1016/j.compositesa.2014.08.015 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. TC is mainly governed by the Al-diamond interface characteristics, which are determined by a proper control exerted through processing conditions. Albeit a very low cost and low quality diamond is used, a high value of 667 W/mK has been measured for Al/diamond composites produced under optimized processing conditions. Values above 740 W/mK are reported for the best diamond quality explored in this work. These experimental results, which assign the control over TC mainly to the interface conductance, suggest that many of the limiting values of TC reported in literature for the different explored metal-diamond systems, need to be reconsidered by proper precise control of interface evolution. ON CRITICAL ASPECTS OF INFILTRATED