In order to study the effect of thermoplastic tackifier addition on the dry fiber placement-RTM(resin transfer molding) process

T-peel test was utilized to determine the mass fraction of PA-6 tackifier. Combining the test with process simulation

the effect of tackifier on the in-plane permeability of preform with PA-6 as the tackifier was studied. The mold filling process was stimulated and analyzed. On this basis

the influence of tackifier on the interlaminar properties and toughness of epoxy composites was studied. The test and simulated results of permeability of preform with tackifier showed that the permeability of fiber preform in parallel with and perpendicular to fiber direction reduced by 55.5% and 52.0%

respectively. The test results were consistent with the revised simulated results

and the deviation values of filling time with different penetration distances were all smaller than 10%. The results of mechanical test showed that the toughness of epoxy composites could be enhanced significantly by adding thermoplastic tackifier. The mode Ⅰ and Ⅱ interlaminar fracture toughness improved by 89.3% and 54.1%

respectively. While the impact toughness improved by 18.7%

the interlaminar shear strength reduced by 23.6%.