Thermoplastic polyurethane/clay nanocomposite foam made by batch foaming

Abstract

In this study, the foaming of nonwoven fabrics and bulk polymers was investigated. Four different polymers that are commonly used for textiles including polyethylene terephthalate, thermoplastic polyurethane, thermoplastic polyether ester elastomer and polypropylene were foamed by batch foaming. Among the polymers, thermoplastic polyurethane seems to be the most promising material since it possesses the highest cell density and smallest cell size. In addition, nanoclay was added to thermoplastic polyurethane to promote cell nucleation and to increase the cell density. The results showed that well dispersed nanoclay in thermoplastic polyurethane served as an excellent nucleation agent and the cell structure was improved. The cell size of thermoplastic polyurethane nanocomposite foam decreased to 1 µm while the cell density increased to 3 × 10¹¹ cells/cm³.

Keywords

Cell nucleation nucleating agent cell density thermoplastic foams diffusivity

Get full access to this article

View all access options for this article.

References

Okamoto

. Microcellular processing, Cincinnati, OH: Hanser Gardner Publications, 2003.

Hobbs

Lesser

. In situ drawing of high molecular weight poly(ethylene terephthalate) in subcritical and supercritical CO₂. J Polym Sci Part B: Polym Phys 1999; 37: 1881–1891.

Hobbs

Lesser

. Preparation of high performance poly(ethylene terephthalate) fibers: two-stage drawing using high pressure CO₂. Polymer 2000; 41: 6223–6230.

Hobbs

Lesser

. Drawing in high pressure CO₂ – a new route to high performance fibers in memory of the Late Roger Porter. Polym Eng Sci 2001; 41: 135–144.

Garcia-Leiner

Song

Lesser

. Drawing of ultrahigh molecular weight polyethylene fibers in the presence of supercritical carbon dioxide. J Polym Sci Part B:Polym Phys 2003; 41: 1375–1383.

Lesser

. Influence of interchain forces and supermolecular structure on the drawing behavior of nylon 66 fibers in the presence of supercritical carbon dioxide. J Appl Polym Sci 2004; 93: 2282–2288.

Krause

Kloth

Van der Vegt

NFA

. Porous monofilaments by continuous solid-state foaming. Ind Eng Chem Res 2002; 41: 1195–1204.

Hirogaki

Tabata

Hisada

. An investigation of the morphological changes in poly(ethylene terephthalate) fiber treated with supercritical carbon dioxide under various conditions. J Supercrit Fluids 2006; 38: 399–405.

Guo

Xiong

Zhu

. Study on the preparation of a novel microcellular fiber. E-Polymers 2006; 1–9.

10.

Zheng

Lee

Park

. Extrusion foaming behaviors of PET with CO₂. SPE ANTEC Tech Papers 2007; 3020–3024.

11.

Travelute FL, Reese GP and Edwards WL. Low density light weight filament and fiber, US Patent, 20060057359A1, 2006.

12.

Choi YB, Lee YH and Han IS. Microcellular foamed fiber, and a process of preparing for the same, US Patent, 7097905 B2, 2006.

13.

Liu

Shen

Lee

S-H

. Electrospinning in compressed carbon dioxide: hollow or open-cell fiber formation with a single nozzle configuration. J Supercrit Fluids 2010; 53: 142–150.

14.

Lee

Zeng

Cao

. Polymer nanocomposite foams. Compos Sci Technol 2005; 65: 2344–2363.

15.

Colton

Suh

. The nucleation of microcellular thermoplastic foam with additives: part I: theoretical considerations. Polym Eng Sci 1987; 27: 485–492.

16.

Michaeli

Heinz

. Foam extrusion of thermoplastic polyurethanes (TPU) using CO₂ as a blowing agent. Macromol Mater Eng 2000; 284-285: 35–39.

17.

Ito

Matsunaga

Tajima

. Generation of microcellular polyurethane with supercritical carbon dioxide. J Appl Polym Sci 2007; 106: 3581–3586.

18.

Pattanayak

Jana

. Thermoplastic polyurethane nanocomposites of reactive silicate clays: effects of soft segments on properties. Polymer 2005; 46: 5183–5193.

19.

Chavarria

Paul

. Morphology and properties of thermoplastic polyurethane nanocomposites: effect of organoclay structure. Polymer 2006; 47: 7760–7773.

20.

Dan

Lee

Kim

. Effect of clay modifiers on the morphology and physical properties of thermoplastic polyurethane/clay nanocomposites. Polymer 2006; 47: 6718–6730.

21.

Crank

. The mathematics of diffusion, Oxford: Clarendon Press, 1975.