Cellular Materials

Abstract

This article is concerned with the general theory of expansion, manufacturing processes, properties, and applications of foamed (cellular) plastics. The high strength‐to‐weight ratio, excellent insulating properties, and cushioning properties of cellular plastics have contributed to the development and growth of the broad range of cellular plastics in use. The total usage of foamed plastics in the United States has risen from 1.4 million metric tons in 1982 to 2.2 million metric tons in 1992 and has been projected to rise to about 3.1 million metric tons in 2002. The manufacturing processes for cellular polymers are described in terms of three classified methods on the basis of cell growth and stabilization processes. The properties of cellular plastics, including mechanical, thermal, electrical, and environmental aging properties, are summarized. A general discussion is given on the properties of cellular plastic necessary in many applications such as the comfort cushioning, thermal insulation, packaging, structural components, buoyancy, electrical insulation, and space‐filling markets. A brief discussion is also given on the process economics, raw materials, and energy considerations for the commercial products of primary importance.

A Review of Rigid Polymeric Cellular Foams and Their Greener Tannin-Based Alternatives

“… The physical mechanisms for their shaping : irreversible hardening under the action of heat to obtain thermosetting materials [ 22 ], or reversible shaping by softening under the action of heat to shape thermoplastic foams [ 23 ], or by crosslinking in elastomers [ 24 ]. The mechanical behavior under a light load : rigid and brittle foams, or flexible and deformable foams, without rupture under load (rubber-like behavior), or semi-rigid foams with an intermediate behavior [ 25 ]. …”

“…The mechanical behavior under a light load : rigid and brittle foams, or flexible and deformable foams, without rupture under load (rubber-like behavior), or semi-rigid foams with an intermediate behavior [ 25 ].…”

Lignin modifications and perspectives towards applications of phenolic foams: A Review

“…The diffusion of gas in the solid phase is a key process in foam manufacturing to achieve a foam structure. Gas diffusion in the continuous phase affects the structural parameters, such as the density, cell type (open or closed), and cell size distribution, which influence the final characteristics and properties of the foams (Imeokparia et al 2002;Eaves 2004;Lee et al 2007).…”

Multiscale Characterization and Modelling of Polyurethane Foams

“…the foam at the densification strain D (Gibson & Ashby, 1999;Imeokparia et al, 2003;Fátima Vaz & Fortes, 1993). Figure 1.6: Typical stress-strain curve of a PU foam in compression (Gibson & Ashby, 1999).…”