Neat resin, adhesive and composite properties of reactive additive/PETI-5 blends

摘要

PETI-5 (5000 g/mole) is a new adhesive and composite matrix that exhibits good processability and excellent properties. However in the fabrication of complex composite parts, better processability may offer distinct advantages. In an effort toimprove the processability of PETI-5, a novel reactive additive was prepared and used to formulate blends. Due to the synthetic approach, the reactive additive is a mixture of relatively simple phenylethynyl containing imides. As such, it exhibitedsolubility in a variety of solvents such as N-methyl-2-pyrrolidinone, a relatively low softening temperature (～l85°C) and a low melt viscosity (～l-3 poise at 250°C). Neat resin blends were prepared by physically mixing imide powders of the reactiveadditive and PETI-5. The resultant powders were used to perform thermal and rheological characterization. Blends were also prepared by mixing NMP solutions of PETI-5 amide acid and the reactive additive (imide form). These solutions were subsequently used to prepare adhesive film and unidirectional carbon fiber tape using unsized IM-7 fiber. The reactive additive/PETI-5 blends were used to fabricate titanium adhesive panels and composites under 0.54 MPa or less for 1 hr at 350-3710C. The effect of reactive additive content on the physical, rheological, adhesive and carbon fiber laminate properties was determined. One formulation exhibited a decrease in melt viscosity (i.e. improved processability) without effecting open hole compression, compression afterimpact properties or microcrack behavior. The neat resin, adhesive and composite properties of these reactive additive/PETI-5 blends and their cured polymers will be presented.