Temperature and Mold Size Effects on Physical and Mechanical Properties of a Polyurethane Foam

Authors

Dacia Jackovich, University of Nevada, Las VegasFollow
Brendan O'Toole, University of Nevada, Las VegasFollow
Michelle C. Hawkins, University of Nevada, Las Vegas

Document Type

Article

Publication Date

3-2005

Publication Title

Journal of Cellular Plastics

Volume

41

Issue

2

First page number:

153

Last page number:

168

Abstract

Rigid polyurethane foams are used as thermal or vibration insulators and energy absorption material, and are often molded directly in place, where a smooth, thin skin forms between the mold and the cellular structure. Density gradients and the presence of a skin are known to affect the mechanical properties of the foam. We investigate the effect of processing temperature (25, 40, 65, and 85 C) and mold size (aluminum cylinders with diameters of 29, 41, and 51mm) on the average density and density gradients (radial and vertical) of a free-rise, water blown, rigid polyurethane foam system, and measure the effects on compressive modulus of elasticity and collapse stress. In general, both average density and radial density gradients decrease with increasing processing temperature and larger mold sizes. A reduction in average foam density corresponds with decreases in the elastic modulus and compressive strength. These mechanical properties are compared to reference samples extracted from very large batches of foam with a uniform density of 0.10 g/cc, where normalization of the compressive data shows the elastic modulus to exhibit the strongest dependence on processing temperature and mold size.

Keywords

Density gradients; Foamed materials – Density; Foamed materials – Mechanical properties; Manufacturing processes; Mechanical properties; Polyurethane foam; Polyurethanes – Density; Polyurethanes – Mechanical properties; Processing effects

Disciplines

Materials Science and Engineering | Mechanical Engineering | Mechanics of Materials | Polymer and Organic Materials

Language

English

Permissions

Use Find in Your Library, contact the author, or interlibrary loan to garner a copy of the item. Publisher policy does not allow archiving the final published version. If a post-print (author's peer-reviewed manuscript) is allowed and available, or publisher policy changes, the item will be deposited.

Repository Citation

Jackovich, D., O'Toole, B., Hawkins, M. C. (2005). Temperature and Mold Size Effects on Physical and Mechanical Properties of a Polyurethane Foam. Journal of Cellular Plastics, 41(2), 153-168.