Abstract
The author investigated the combinational effect of two kings of epoxy terminated poly（oxytetramethylene）glycols E-PT with diglycidylether of bisphenol-A（ DGEBA）. Molecular weight（s Mn） of E-PT were 870（6ET） and 2016（20ET） respectively. Blends of 6ET and 20ET were added to DGEBA, then the mixtures were cured by typical tertiary amine. We examined the physical properties of cured epoxy resins which were varied blend ratio and adding amount of 6ET and 20ET. Adhesive properties（ T-peel strength and tensile shear strength） of blend ratio 5/5 system greatly increased at 20phr in comparison to two individual（ no-blend） systems and other blend systems. This behavior of blend system is remarkable characteristic. Regarding blend systems of 6ET and 20ET, bending properties and fracture toughness indicated higher value and maximum value shifted to higher adding amount side as blend ratio of 6ET increased. We revealed that the morphology of blend ratio 5/5 system was closely related to various physical properties. In concrete terms, fracture toughness held high value in micro phase separation structure of the sea and island type with fine particle, and adhesive properties showed high strength in roundish uneven morphology. It was clarified that various physical properties were greatly influenced by different morphology caused by blend ratio and adding amount of blends of 6ET and 20ET.
