Polyurea RIM-A Versatile High Performance Material

Abstract

Polyurethane elastomers were the first products to find wide commercial use in the RIM process. Recently, the advent of a new chain extender, diethyltolu enediamine (DETDA), provided another class of commercially useful RIM elas tomers. These materials are best classified as polyurethane/urea elastomers. We have been working on the next logical step in this evolution: amine- terminated polyether resins with amine chain extenders. These are best classi fied as polyurea elastomers. Amine-terminated polyether resins, or polyether polyamines, can replace the polyol in a RIM formulation. These materials are much more reactive than pol yols, and their composition can be varied more easily than conventional RIM polyols. Thus, these products can be tailored to meet the performance require ments of a particular end use more easily than polyols. The use of amine-terminated polyether products in RIM applications brings a new dimension to the RIM process. Depending on the choice of amine termi nated polyether amine, one can formulate systems covering a broad range of properties from elastomeric materials to rigid materials. Elastomeric materials are made by having a small amount of hard segment in a block-copolymer in conjunction with a polyether diamine. These elasto meric materials can be more closely tailored to meet a specific physical prop erty by either adjusting the formulation or by adjusting the density of the polymer. Very rigid materials can also be made by increasing the amount of hard seg ment in the block-copolymer in conjunction with a polyether triamine. High levels of an aromatic diamine chain extender can be used with the polyether triamine.

Polyurea Body Panel for On-Line Painting

“…These catalysts can, at high temperatures, promote the reverse reaction kinetics and decompose the polymer. The same results have been noted by other researchers [5,6,7,8]. Therefore the keys to high thermal resistance in non-crystalline polyurethane/ urea RIM polymers are: Polymerization in the absence of catalyst and a high degree of phase separation.…”

Microdispersive interfacial mixing in fast polymerizations

“…Such chemical systems yield materials with excellent mechanical properties (Grigsby and Dominguez, 1985;Ewen, 1985;Vespoli et al, 1986), but rapid gelation, generally occurring in less than 1 s (Vespoli et al, 1986;Pannone and Macosko, 1987), results in large domains of unreacted species in the RIM product material. Since the extent and control of fluid mechanical mixing is limited by the rising viscosity, any microscopic interfacial mixing process must somehow be controlled and optimized for successful molding of such chemical systems.…”

Polyurea RIM: Novel Applications and Technical Advances

“…Polyurea RIM materials are the most recent development to result from this effort [3][4][5]. In this paper we will discuss some recent advances in polyurea RIM technology.…”