Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1990. / Includes bibliographical references (leaf 51). / by Maureen Theresa Fahey. / B.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1994. / On t.p., "g" is subscript. / Includes bibliographical references (p. 98). / by Rafael Levin. / M.S.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006. / Includes bibliographical references (leaf 56-60). / Polyelectrolyte multilayered (PEM) films created by an aqueous-based layer-by-layer assembly technique have been widely studied in the past decade. Owing to the simple, versatile and yet well-controlled nature of this technique, many potential applications of these thin films have also been proposed and explored. This thesis presents a recent work in fabricating nanoporous PEM films with superhydrophilic characteristics that demonstrate great promise for anti-fogging and anti-reflection glass coating applications. The automotive glass industry is then identified as a potential market for this technology, and competing anti-fogging technologies as well as relevant intellectual property are reviewed to further ascertain the commercial viability of this product. Finally a few possible business models for bringing this product to market are proposed and evaluated. / by Jonathan Tze Ming Lim. / M.Eng.

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1999. / Includes bibliographical references (p. 261-267). / by Brian James Gally. / Sc.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1998. / Includes bibliographical references (p. 235-245). / by Benjamin M. Wu. / Ph.D.

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2016. / "September 2016." Cataloged from student-submitted PDF version of thesis. / Includes bibliographical references (pages 155-171). / Kinetic Monte Carlo (Kc) methods have the potential to extend the accessible timescales of off-lattice atomistic simulations beyond the limits of molecular dynamics by making use of transition state theory and parallelization. However, it is a challenge to identify a complete catalog of events accessible to an off-lattice system in order to accurately calculate the residence time for Kc. Possible approaches to some of the key steps needed to address this problem are developed in this thesis. After validating these methods in the study of vacancy diffusion, we implemented our off-lattice Kc method to study the kinetic behavior of the [Sigma]5 (210) grain boundary (GB) in copper. We found that the activation energy associated with intrinsic diffusion at this GB is between the activation energies of interstitial diffusion and vacancy diffusion. We have also measured GB mobility in this system and found the activation energy of GB migration to be similar to that of bulk diffusion. For comparison, we have performed a molecular dynamics study of this target GB and obtained diffusivity and mobility estimates that are sufficiently similar to our Kc results at high temperatures. At low temperatures, the molecular dynamics simulations did not yield meaningful predictions. The results of this case study indicate that the off-lattice Kc method developed herein may provide a means to study GB kinetic properties under conditions and timescales that were previously inaccessible. Towards the end of developing predictive relationships to describe GB kinetic properties, we have begun to assess whether the normalized ground state residence time of a GB is a good predictor of kinetic behavior by analyzing several low-CSL GBs. We see a clear relationship between normalized ground state residence time and kinetic properties for the GBs considered so far. A more thorough investigation will be required to establish whether or not these preliminary findings indicate a more general relationship. / by Kathleen Carmody Alexander. / Ph. D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2003. / Vita. / Includes bibliographical references. / Diblock copolymers incorporating liquid crystallinity via a lateral attachment of mesogenic species to a flexible backbone were studied for their microstructure-property relationships. Two families of materials were studied, distinguished primarily by the method of attachment of the mesogen to the polymer. In the first, azobenzene based mesogens were covalently tethered to the isoprene blocks of a poly(styrene)-block-poly(isoprene), P(S-b-ILC), series of diblock copolymers. In the second family of polymers, hydrogen bonding was used to complex bi-phenyl based mesogens to the acrylic acid units of a poly(styrene)-block-poly(acrylic acid), P(S-b-AA) diblock copolymer. The morphology of the P(S-b-ILC) system was characterized as a function of composition, and clear correlations between the microphase separated structure and the thermal properties of the liquid crystalline mesophase were observed and accounted for. Control of the hierarchical structure in these materials was pursued and achieved independently via surface epitaxy, oscillatory shear and, for the first time in this class of materials, via magnetic fields. It was found that the morphology adopted by the material under the external fields is strongly dependent on the orientation of the liquid crystalline mesophase with respect to the inter-material dividing surfaces present due to the microstructure. Oscillatory shear of a P(S-b-ILC) resulted in the first observation of a novel transverse cylindrical microdomain morphology in one case. The investigation of hydrogen-bonded side-group liquid crystalline block copolymers based on P(S-b-AA) followed a screening of several other candidate host diblock-mesogen pairs. The structure and thermal properties of a model P(S-b-AA) diblock and a homopolymer acrylic acid complexed with mesogens were studied and characterized as a function of composition. A high molecular weight analogue, based on poly(styrene)-block-poly(methacrylic acid), P(S-b-MAA), was successfully / (cont.) complexed with mesogens to produce a lamellae- forming liquid crystalline diblock copolymer with a very large repeat distance. The material exhibited a photonic band gap with a stop-band in the visible. It is the first example of a self-assembled coil block-LC block copolymer photonic crystal. The material was characterized optically and changes in temperature were used to reversibly manipulate the efficiency and location of the stop-band. The optical properties of the polymer as a function of temperature were correlated to changes in the order parameter of the liquid crystalline phase, observed as a function of temperature. / by Chinedum Osuji. / Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005. / Includes bibliographical references (leaves 77-81). / Wafer-level, thermocompression bonding is a promising technique for microelectromechanical systems (MEMS) packaging. The process is a form of solid-state joining and requires the simultaneous application of temperature and pressure to wafers patterned with metallic thin films in order to bring the mating surfaces into atomic proximity. The quality of the resulting bond is critically dependent on the interaction between flatness deviations that range from wafer bow to surface roughness, the thin film properties and the process parameters and tooling used to achieve the bonds. Hitherto there has been limited modeling applied to understand the relative contributions of these effects. This thesis addresses the above issue through the development of a mechanics-based framework that allows the effect of flatness deviations to be assessed for typical geometries and process conditions. The strain energy release rate associated with the elastic deformation required to overcome wafer bow is calculated. A contact yield criterion is used to examine the pressure and temperature conditions required to flatten surface roughness asperities in order to achieve bonding over the full apparent area. The results are compared to experimental data of bond yield and toughness obtained from four-point bend delamination testing, microscopic observations and measurements on the fractured surfaces. Conclusions from the modeling and experiments indicate that wafer bow has negligible effect on determining the variability of bond quality and that the well-bonded area is increased with increasing bonding pressure. / (cont.) The enhanced understanding of the underlying deformation mechanisms allows for a better controlled trade-off between the bonding pressure and temperature. / by Konstantinos Stamoulis. / S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1997. / Includes bibliographical references (p. 41-42). / by Erin Baker Lavik. / M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1998. / Includes bibliographical references (p. 92). / by Thomas Besson. / M.S.