Polyimide-polysiloxane block　 copolymers, which contains both aromatic polyimides as hard-segment and siloxane as soft-segment, are used as high performance adhesives and specialty coatings. In the present study, surface viscoelastisity of the copolymer was analysed by phase detection-mode of AFM, and then a novel information was given concerning the viscoelastic properties at the nano-meterscale. The morphological organization changed with increase of polysiloxane content in the copolymers. Co-continuous lamellae organization was obserbed on the surface of copolymer with 50wt% of polysiloxane. In addition, complex nano-level unevenness of the surface was given and the topographical changes depended on the polysiloxane composition and the polysiloxane chainlength.

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The initial state of crack propagation for the push-out test was analyzed using finite element method. The effects of thermal residual stress and the surrounding fibers were considered in the calculation of the energy release rate. The comparison of the energy release for the cracks at the indenter side and the support side indicates the following conclusion: The lower matrix modulus corresponding to polymer matrix composites yields the on set of delamination from the support side; the higher matrix modulus corresponding to the ceramic matrix composites yields the onset of delamination from the indenter side. Then, this analysis was tried to apply for the results of the push-out test for a glass matrix composite, SiC/LAS (LithiumAluminosilicateGlass). Scanning electron microscopy indicated the existence of the coating carbon layer delamination of the length of 5µm only at the tip of the indenterside. The slope of experimental load-displacement diagram agreed with that of FEM simulation where perfect bonding of interface was assumed. The interfacial fracture toughness of SiC/LAS was calculated to be 26J/m2 from the push-out displacement and the initial delamination length.

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Isocyanate-terminated　urethanes　with　polyoxypropylene　glycols　(PPGs)　as　a　softsegment　were　reacted　with　the　mixture　of　two　bisphenol-A type epoxy resins which had secondary hydroxy groups. One component epoxy adhesives were prepared with the epoxy resins chain extended by polyurethanes (PUs) and dicyandiamide as a hardener. The relationships between the properties of cured epoxy resins and molecular weight (MW) of PPGs in PUs were investigated. The MW of PPGs remarkably affected the adhesive properties and morphology. In case of PPG-Diol, the compatibilities of PPGs/epoxy resin decreased with the increasing MW of PPGs. The dynamic viscoelastic properties showed that the higher MW-PPGs were easy to form the phase separation structures. The adhesive strength about Diol-2000 type was the highest in all PPGs. The hydroxy group equivalent of PPGs was one of the most important factor about the compatibility between epoxy resin and PUs because of the similar properties of adhesive strength and morphology about Triol-3000 and Diol-2000 type.

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