Organic-inorganic hybrids containing various amounts of alumina were synthesized from epoxy resin and aluminum alkoxide via a sol-gel process. The phase structure and thermal and mechanical properties of the epoxy/alumina hybrids were studied in detail. It was revealed by transmission electron microscope (TEM) observations that the fine alumina network about 5 nm in size are uniformly dispersed throughout the epoxy matrix. The storage modulus in the rubbery region increased and the peak area of tan d curve at glass transition region decreased with the hybridization of small amounts of alumina. Moreover, the thermal and mechanical and conductive properties of the hybrid systems which were filled with a conductive filler were analyzed. The hybrid systems indicated stable conductivity even in the high temperature region. This is due to the suppression of the network chain motion with the hybridization of alumina networks.

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The stress behavior in laminated cantilever beams with adhesive layers under impact loadings are analyzed in an elastic region using three-dimensional finite element method (FEM). FEM code employed is DYNA3D. The stress wave propagation and the stress distribution at the adhesive interfaces are examined. In the experiments, the end of the beam is fixed and the other end of the one is subjected to an impact loading. An impact loading is applied to a beam by dropping a weight. The effects of Young’s modulus of the adherends, the adherend thickness, impact velocities, and the number of adhesive layers on stress statements at the interfaces are clarified. The following results are obtained. (1) The maximum principal stress (s1) in the adhesive layers are maximal at the adhesive interfaces. (2) It is found that the maximum principal stress (s1) at the interfaces increases as Young's modulus of the upper adherends increases. (3) The maximum principal stress(s1) at the interfaces decreases as the thickness of the adherend to which an impact loading is applied increases. (4) No difference in the tendency on the maximum principal stress (s1) distribution although the value of the one is proportional to the impact velocity. (5) The effect of the number of layers was found to be small on stress statement. (6) Experiments were carried out to measure the strain response of the adhesively laminated cantilever beams using strain gauges. A good agreement is seen between the tendencies of the analytical and experimental results.

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Poly(hexene-l) (PHX) was modified by a chemical grafting of maleic anhydride (MAH) in a benzene solution. The degree of grafting, as determined by FT-IR analysis, was found to be controlled between 1.0 and 6.7% depending on reaction conditions. The maximum adhesives hear strength of MAH-modified PHX (m-PHX), at a degree of grafting 1.6%, to aluminum plate was estimated to be 0.53 MPa, which was higher than that of chloroprene rubber. The grafting of MAH on to PHX could contribute to an increase in the relative adhesive strength between m-PHX and aluminum plate.

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