Microcellular Polymers: Novel Materials for the 21st Century

Abstract

Microcellular polymer's produced by gas nucleation, refer to closed cell thermoplastic foams with a very large number of very small cells—typically 10⁸or more cells per cm³ of order 10 μm in diameter. First produced in the early 1980's with the objective of reducing the amount of polymer used in mass produced items, these novel materials have the potential to revolutionize the way thermoplastic polymers are used today. Microcellular plastics have been produced from a number of polymers ranging in relative density from 0.1 to 1.0, containing 10⁸ to 10¹¹ cells per cm³, offering the engineer a new range of properties for design. The microcellular polymers appear to possess improved fatigue life and energy absorption characteristics as well as a higher specific strength. This paper reviews recent progress in this emerging technology and discusses the areas where this technology is likely to make an impact in the future.

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References

Martini

J.E.

, Waldman

F.A.

and Suh

N.P.

, “The Production and Analysis of Microcellular Thermoplastic Foams”, SPE Technical Papers, Vol. 28, 1982, 674

Kumar

and Weller

J.E.

, “Process A to Produce Microcellular PVC”, International Polymer Processing, Vol. VIII (1993), Issue 1, 73

Kumar

, Weller

J.E.

and Hoffer

H.Y.

, “Synthesis of Microcellular Polycarbonate: Phenomenological A Study of Bubble Nucleation and Growth”, Symposium on Processing of Polymers and Polymeric Composites ASME Winter Annual Meeting, Dallas, Nov. 1990, Vol. MD-19, 197

Durril

P.L.

and Griskey

R.G.

, “Diffusion and Solubility of Gases in Thermally Softened or Molten Polymers”, AlCh E Journal, Vol. 15, 1969, 106

Kumar

and Weller

J. E.

, “Production of Microcellular Polycarbonate using Carbon Dioxide for Bubble Nucleation”, to appear in ASME Journal of Engineering for Industry, 1993.

Colton

J.S.

, “The Nucleation of Thermoplastic Microcellular Foam”, Ph. Thesis D., Mech. Eng. Dept., MIT, 1985

Kumar

, “Process Synthesis for Manufacturing Microcellular Thermoplastic Parts: Case A Study in Axiomatic Design”, Ph.Thesis D., Mechanical Engineering MIT, May 1988

Ramesh

N.S.

, Kweeder

J. A.

, Rasmussen

D.H.

and Campbell

G.A.

, “An Experimental Study of the Nucleation of Microcellular Foams in High Impact Polystyrene”, SPE Technical Papers, Vol. 38, 1992, 1078

Kweeder

J.A.

, Ramesh

N.S.

, Campbell

G.A.

and Rasmussen

D.H.

, “The Nucleation of Microcellular Polystyrene Foam”, SPE Technical Papers, Vol. 37, 1991, 1398

10.

Kumar

and Suh

N.P.

, “Structure of Microcellular Thermoplastic Foam”, Proceedings of the SPE ANTEC ‘88, Vol. XXXIV, April, 1988, 715

11.

Kumar

and Gebizlioglu

O.S.

, “Carbon Dioxide Induced Crystallization in PET Foams“, Proceedings of the SPE ANTEC ‘91, Vol. XXXVII, 1991, 1297

12.

Baldwin

D.F.

and Suh

N.P.

, “Modelling Gas Sorption in Semicrystalline Polymers”, Proceedings of the SPE ANTEC ‘91, Vol. XXXVII, 1991, 1300

13.

Vanderwel

, “Microcellular Polycarbonate: Characterization of Tensile Behavior”, Thesis

M.S.

, University of Washington, 1991

14.

Kumar

, Weller

J.E.

, VanderWel

and Seeler

K.A.

, “Experimental Characterization of the Tensile Behavior of Microcellular Polycarbonate”, to appear in ASME Journal of Engineering Materials and Technology, 1993

15.

Waldman

F.A.

, “The Processing of Microcellular Foam,” Thesis S.M., Mech. Eng. Dept., MIT, 1982.

16.

Kumar

and Seeler

K.A.

, “Fatigue of High Density Microcellular Polycarbonate”, to appear in SPE Technical Papers, Vol. 39, 1993

17.

Park

and Suh

N.P.

, “Extrusion of a Microcellular Filament”, Cellular Polymers Kumar

and Advani

S.G.

, editors; MD Vol. 38, ASME 1992, 69

18.

Kumar

and Suh

N.P.

, “Process A for Making Microcellular Thermoplastic Parts”, Polymer Engineering and Science, Vol. 30, 1990, No. 20, 1323–1329

19.

Kumar

and Weller

J.E.

, “Creating an Unfoamed Skin on Microcellular Foams”, SPE Technical Papers, Vol. 38, 1992, 1508

20.

Garbini

J.L.

, Holl

, Kumar

, Murray

W.M.

and Jorgensen

J.E.

, “Non-Destructive Characterization of Microcellular Foam Structure: Analysis of a Proposed Sensor”, SPE Technical Papers, Vol. 38, 1992, 1519

21.

Holl

, University of Washington, Seattle USA, unpublished data.