Fabrication, Evaluation and Radiation Behavior of S2-Glass Fiber Reinforced Polyimide Laminates for Cryogenic Applications

Abstract

A number of thermosetting polyimide resin formulations have been prepared evaluated and used in the resin transfer molding (RTM) fabrication of S2-glass reinforced composite laminates. The resin formulations are based on combining varying amounts of 3, 4'-oxydianiline and 4, 4'-(1,3-phenylenedioxy) dianiline with 4, 4'-bisphenol A dianhydride and 3, 3', 4, 4'-benzophenone tetracarboxylic dianhydride and terminated in 4-phenylethynyl phthalic anhydride. The initial viscosity and working life of the resins were measured to determine suitability for RTM. Composite laminates were prepared by degassing and then transferring the resins at 260 or 270 °C. A laboratory RTM system with process capabilities to 300°C and 2000 psi, was built and utilized. The polyimide matrix was cured at 320 and 340°C, with a dwell for 3 h at each temperature, under 280 psi hydrostatic pressure. The effect of three different Co-60 gamma irradiation doses on cryogenic (77K) mechanical and thermal properties was determined. Performance was compared to that of laminates prepared from a commercially available bismaleimide (RTM-651®). The composites are being studied for their potential use as the electrical insulation in the super-conducting magnet coils of future fusion reactor devices such as the International Thermonuclear Experimental Reactor.

Novel acetylene‐terminated polyimide oligomers with excellent processability and high toughness of films

“…The flexible ether linkages in a‐ODPA and 3,4′‐ODA possess improved conformational freedom in the polyimide maintain and contribute to a reduction in viscosity. The asymmetric monomers of a‐ODPA and 3,4′‐ODA reduces the efficiency of chain packing also leading to reduced viscosity at the processing temperature . The low‐weight oligomers made positive contribution towards achieving a low‐melt viscosity, it will provide a broader processing window.…”

Development of novel cardo-containing phenylethynyl-terminated polyimide with high thermal properties

“…Phenylethynyl‐terminated imide (PETI) oligomers have attracted great interest with the characteristics of a wider processing window, good thermo‐oxidative stability, and excellent mechanical properties and so on . They have been widely applied as high‐temperature structural adhesives and the matrices of carbon fiber‐reinforced composites in modern aerospace and aviation industry . The fast growth of electronics and aerospace industries has lead to the developments of PETI oligomers with enhanced properties.…”