摘要
采用以超临界CO2为物理发泡剂的固态间歇发泡技术制备了环氧树脂微孔材料,利用SEM和DSC研究了环氧树脂微孔材料的制备工艺,分析了发泡前后环氧树脂的力学性能和介电性能。结果表明：环氧树脂片材的预固化度为75%～85%时,气体浓度达到5.11%～5.43%,气体饱和时间为48h,泡孔排列紧密尺寸均匀。发泡温度的提高和发泡时间的延长会使环氧树脂微孔材料的平均泡孔直径逐渐增大,泡孔密度逐渐降低。当环氧树脂片材预固化度为75%、发泡温度为120℃、发泡时间为10s时,环氧树脂微孔材料的平均泡孔直径为10.6μm,泡孔密度为1.03×109个/cm3,泡孔呈均匀致密的球形或多边形结构。与未发泡材料相比,环氧树脂微孔材料的断裂伸长率和冲击强度分别提高了43%和39%,介电常数降低了42%,介电损耗降低了50%。
The microcellular epoxy resin was prepared by the solid-state batch foaming technique with supercritical CO2 as a physical-blowing agent.The preparation processes of microcellular epoxy resin were studied by SEM and DSC,mechanical properties and dielectric properties of the epoxy resin before and after foaming were analyzed.The results show that when the pre-curing degree of epoxy resin sheets is 75%-85%,the gas concentration will reach5.11%-5.43%,the gas saturation time will be 48 h,and the cells are closely packed and the size is uniform.With the improvement of foaming temperature and extension of foaming time,the average cell diameter of the microcellular epoxy resin will gradually enlarge and the cell density will decrease.When the pre-curing degree of epoxy resin sheets reaches 75%,the foaming temperature is 120 ℃ and the foaming time is 10 s,the average cell diameter of microcellular epoxy resin will be 10.6μm and cell density will be 1.03×109 cells/cm3.And the cells are uniform and compact spheres or polygons structure.Compared with materials without foaming,the elongation at break and impact strength of the microcellular epoxy resin increase by 43% and 39%respectively.The dielectric constant and the dielectric loss decreases by 42% and 50% respectively.
作者
范晓龙
张广成
李建通
樊勋
FAN Xiaolong ZHANG Guangcheng LI Jiantong FAN Xun(School of Science, Northwestern Polytechnical University, Xi＇an 710072, China)
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2016年第9期1915-1921,共7页
Acta Materiae Compositae Sinica
关键词
超临界CO2
环氧树脂
微孔发泡
泡孔结构
力学性能
介电性能
supercritical CO2
epoxy resin
microcellular foam
cell structure
mechanical properties
dielectric properties
