聚醚砜/碳纳米管对环氧树脂的协同增韧

通过同时添加少量聚醚砜(PESU)及碳纳米管(CNTs)对环氧树脂(EP)进行增强增韧改性。首先采用热溶法使PESU完全溶解在EP中,再利用三辊研磨机的机械剪切作用帮助CNTs分散在EP/PESU体系中,制得EP/PESU/CNTs复合材料浇铸体试样。结果表明,CNTs和PESU的加入,在没有牺牲EP热性能的情况下,试样的断裂韧性、缺口冲击强度、弯曲强度、储能模量得到提高;同时其拉伸强度未受到不利影响。当PESU含量为10份,CNTs含量为0.15份时,试样的断裂韧性和缺口冲击强度达到最大值,分别为5.29 MPa·m1/2和212 J/m,相比纯EP提升49.4%和81.2%;CNTs含量为0.1份时,试样弯曲强度达到最大值216 MPa,相比纯EP提升24.1%。通过扫描电子显微镜分析发现,PESU相分离形成的热塑性微球和CNTs在微米和纳米两个尺度上对EP起到了协同增韧的作用。

Synergistic Toughening of Epoxy Resin with Polyethersulfone/Carbon Nanotubes

Epoxy resin(EP)was reinforced and toughened by adding a small amount of polyethersulfone(PESU)and carbon nanotubes(CNTs)at the same time.First,the hot dissolution method was used to completely dissolve PESU in EP,and then the mechanical shearing action of a three-roll mill was used to help disperse CNTs in the PESU/EP system to prepare PESU/CNTs/EP composite casting samples.The results show that the addition of CNTs and PESU can improve the fracture toughness,notched impact strength,bending strength,and storage modulus of the casting without sacrificing the thermal performance of EP;at the same time,its tensile strength is not adversely affected.When the PESU content is 10 phr and the CNTs content is 0.15 phr,the fracture toughness and notched impact strength of the casting reach the maximum value of 5.29 MPa·m1/2 and 212 J/m,which is an increase of 49.4%and 81.2%compared to pure EP;when the CNTs content is 0.10 phr,the bending strength of the casting reaches the maximum value of 216 MPa,which is 24.1%higher than that of pure EP.SEM analysis show that the thermoplastic microspheres formed by phase separation of PESU and CNTs play a synergistically toughening effect on EP at both micron and nanometer scales.