The majority of this dissertation focuses on proton conducting materials that could be used at high operating temperatures. Higher operating temperatures are desirable as they will increase fuel cell efficiency, reduce cost, and simplify the heat management system. The factors governing proton conduction including segmental mobility, protogenic group identity, and charge carrier density were investigated on a variety of polymers containing 1H-1,2,3-triazole moieties. Proton conductivity measurements were made using AC impedance spectroscopy. Random copolymers and terpolymers of triazole-containing acrylates and poly(ethylene glycol)methyl ether acrylate (PEGMEA) have been synthesized. Conductivity increased with increasing degree of PEG incorporation until reaching a maximum at 30% mole PEGMEA. In comparison to benzimidazole-functionalized polyacrylate with 35% mole PEGMEA, the triazole analog showed a higher proton conductivity, and a less pronounced conductivity temperature dependence. Further increases in conductivity was achieved through the addition of trifluoroacetic acid. To study the effect of charge carrier density on proton conduction, polyacrylates containing a different number of triazole groups per repeat unit were synthesized. The result showed that introduction of more than one triazole per repeat unit did not result in an increase in conductivity as there was an accompanying increase in Tg. To improve the thermal and mechanical properties, triazole groups were tethered to a higher Tg backbone polymer, polynorbornene. Introduction of polyhedral oligomeric silsesquioxane (POSS) into triazole-functionalized polynorbornene was also investigated. In a parallel set of investigations, poly(2-(dimethylamino)ethyl methacrylate), PDMAEMA, and copolymers of DMAEMA and methyl methacrylate (PDMAEMA-co-PMMA) were synthesized via atom transfer radical polymerization (ATRP). Fluorescently-labeled PDMAEMAs were synthesized using fluorescent ATRP initiators to ensure the presence of one dye molecule on every polymer chain. PDMAEMAs and PDMAEMA-co-PMMA with different molecular weights have been deposited onto a negatively-charged silica surface via controlled flow deposition. The results show that the polymer deposition rate depends on molecular weight, and is inversely proportional to molecular weight. A preliminary adhesion study of 1-μm negatively charged silica spheres onto these functionalized surfaces indicates that by varying the molecular weight, the adhesion threshold can be changed. System modeling is being conducted to support experimental observations.

<p dir="ltr">This work focuses on the fracture behavior and failure mechanisms of Prepreg Platelet Molded Composites (PPMCs), which are characterized by meso-structural variability. The study investigates the interlaminar fracture toughness of PPMCs using both experimental and computational approaches, with a particular focus on Mode-I fracture testing. Cohesive zone models are developed to simulate interfacial behavior in composite laminates. The research introduces the concept of the platelet critical length problem and explores how platelet geometry, arrangement, and meso-structural features affect fracture toughness and energy absorption. Findings indicate that smaller platelets enhance fracture toughness through mechanisms like platelet bridging and crack deflection, while larger platelets provide more consistent fracture properties but exhibit greater variability in stiffness. This work offers valuable insights for optimizing PPMC performance in high-performance applications.</p>