Award Date

1-1-2003

Degree Type

Thesis

Degree Name

Master of Science (MS)

Department

Mechanical Engineering

First Committee Member

Brendan O'Toole

Number of Pages

229

Abstract

Polyurethane foam, used as a supporting or insulating material, is sometimes formed in complex molds with significant variations in geometry and size. This work investigates the relationships between cell morphology, density, and mechanical properties in a molded polyurethane material using relatively small cylindrical molds. Understanding these relationships will help mechanical designers analyze and predict the responses of foam components accurately; Three mold sizes are used to study changes in cell morphology (cell area, cell diameter, aspect ratio, cell angle, cell edge length, cell face thickness, and cell edge thickness), density, and mechanical properties (Young's modulus, peak yield, and collapse stress) with respect to vertical and radial positions. In addition, five time periods (1-day, 2-days, 7-days, 30-days, and 90-days) are used to determine aging effects on density and compressive mechanical properties of small diameter molds. Finally, theoretical equations are used to compare the experimental and theoretical density and mechanical properties.

Keywords

Cell; Density; Foam; Mechanical; Morphology; Polyurethane; Properties; Relationship; Rigid

Controlled Subject

Mechanical engineering; Materials science; Polymers; Polymerization; Chemistry; Plastics

File Format

pdf

File Size

12707.84 KB

Degree Grantor

University of Nevada, Las Vegas

Language

English

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Rights

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