Engineering Commons^™

Direct Sheet Molding Compound Process (D-Smc), Atieh Motaghi

Electronic Thesis and Dissertation Repository

The combination of highly crosslinked resin and long glass fiber reinforcement in direct sheet molding compound (D-SMC) provides the parts with high physical properties and low density suitable for large interior and exterior automotive applications. Different stages of D-SMC process including maturation zone and compression molding are studied using mathematical analysis, numerical simulation and experimental investigations.

An analytical analysis is used to calculate the pressure and velocity in the first section of maturation zone and then the permeability of fiber bundle is calculated by simulation and the agreement between the available empirical equation and simulation was obtained. The flow is …

In Mold Flow Of Long Fibers In Compression Molding Process, Gleb Meirson

Electronic Thesis and Dissertation Repository

Long Fiber Thermoplastics (LFT) are promising new materials with high physical properties and low density. These high properties are obtained by embedding very long fibers (~100 mm) into a thermoplastic matrix. Such a high fiber length dictates the use of a compression molding process for manufacturing as the length of discontinuous fibers in injection molding is limited by pellet length.

LFT composites are of great interest for the automotive industry. These materials are already used in some interior and exterior car parts such as bumpers, seat structures, door module etc. This research is inspired by the desire to manufacture load …

In Situ Infrared Study Of The Role Of Peg In Stabilizing Silica-Supported Amines For Co2 Capture, Jak Tanthana, Steven Chuang

Steven S.C. Chuang

The CO(2) capture capacity, adsorption mechanism, and degradation characteristics of two sorbents, silica-supported tetraethylenepentamine (TEPA/SiO(2)) and polyethylene-glycol-modified TEPA/SiO(2) (PEG/TEPA/SiO(2)), are studied by diffuse reflectance infrared Fourier transform spectroscopy and mass spectrometry. The CO(2) capture capacities of TEPA/SiO(2) and PEG/TEPA/SiO(2) are determined to be 2087 and 1110 micromol CO(2) g(-1) sorbent, respectively. Both sorbents adsorb CO(2) as hydrogen-bonding species, NH(2)--O, and carbamate/carboxylate species. The CO(2) adsorption half-time increases with the number of CO(2) capture cycles. Infrared results suggest that the increased adsorption half-time is a result of diffusion limitation, caused by accumulation of TEPA and PEG species on the surface of …

Polymer Composites And Porous Materials Prepared By Thermally Induced Phase Separation And Polymer-Metal Hybrid Methods, Joonsung Yoon

Open Access Dissertations

The primary objective of this research is to investigate the morphological and mechanical properties of composite materials and porous materials prepared by thermally induced phase separation. High melting crystallizable diluents were mixed with polymers so that the phase separation would be induced by the solidification of the diluents upon cooling. Theoretical phase diagrams were calculated using Flory-Huggins solution thermodynamics which show good agreement with the experimental results. Porous materials were prepared by the extraction of the crystallized diluents after cooling the mixtures (hexamethylbenzene/polyethylene and pyrene/polyethylene). Anisotropic structures show strong dependence on the identity of the diluents and the composition of …