Benzoxazine(BOZ) with low curing shrinkage was used to modify epoxy in liquid composite molding(LCM) process.The purpose was to reduce curing shrinkage of epoxy greatly

while the heat resistance

manufacturability and mechanical property did not decrease.The curing shrinkage property

curing reactivity

LCM manufacturability and mechanical properties of modified resins with different contents of BOZ were studied.Then the composites reinforced by unidirectional carbon fiber fabric were prepared by vacuum assisted resin infusion(VARI) process

and the mechanical properties of the composites were studied.The results show that the addition of BOZ basically has no influence on the curing reactivity

LCM manufacturability and heat resistance of epoxy.The curing shrinkage of modified resin decreases with the increasing of the BOZ content

andthe curing shrinkage of modified resin with 15 wt% BOZ decreases by about 79%

compared to the unmodified resin.Simultaneously

the tensile strength of the modified resin increases by about 19%

as well as the impact strength increases by about 148%.Moreover

the tensile strength and the interlaminar shear strength(ILSS) of the modified resin based composite improve by about 23% and 9% respectively

relative to the unmodified resin based composite.Namely

the mechanical properties and the interface bonding properties of the modified resin based composite are superior.