Honeycomb sandwich panel has the advantage of being light and rigid. By utilizing this advantage.the panel has been applied to various types of industrial products such as aerospace, airplane, railway,and buildings. Production cost needs to be reduced to further expand the panel usage. Such demandto reduce the production cost necessitates a reduction in the amount of adhesives used in the panel.To meet such needs, we have attempted to make a sandwich panel with adhesives dispensed in stripedpattern. In this structure, the sandwich panel specimens were fabricated by striped dispensing ofacrylic adhesives onto an aluminum plate and aluminum honeycomb pallet using a comb-typetrowel. The adhesive strength was estimated using peel torque and bending test.Striped dispensing is more advantageous than dispensing flatly in terms of both peel torque andbending property when adhesive amount is below 150g/m2. Also, when adhesive dispensed was about130g/m2, larger bending strength was confirmed at small interval of adhesive stripe than that of wideinterval stripe with higher adhesive fillet.Though equivalent bending property was confirmed using adhesive amount of about 225g/m2both striped dispensing and dispensing flatly, higher peel torque was shown in striped dispensing thanthat of dispensing flatly as previously reported. It is due to the difference in effective height of adhesive fillet that different results occurred in peel torque and bending property.As a result of the associated bond strength and distribution of the adhesive, a monotonic increaseof bending stiffness and strength were observed inaccordance with the height of the fillet and contactratio of adhesive and honeycomb, on the other hand peel torque increased rapidly more than 0.68mmin height of adhesive fillet. It is considered the difference of this point would have affected the differ once between striped dispensing and dispensing flatly.From the results of these studies, striped dispensing is not only a useful method to reduce theamount adhesives from the perspective of bonding honeycomb and surface plate, but striped disponsing is also an effective method to ensure the bending stiffness of the sandwich panel.

Reactivity of silane coupling agent with various inorganic particles was investigated. For this purpose, surface treatment of silica, alumina and calcium carbonate particles with silane coupling agent having glycidoxy and amino groups by wet-treatment method using 2-propanol as solvent was carried out. Physical adsorbed molecules were removed by alcohol washing, and the adsorption percent was measured by thermogravimetric analysis. In the case of glycidoxy functional silane, the adsorption was about 35% for silica and about 5% for alumina and calcium carbonate. In the case of amino functional silane, it was about 60% for silica, about 35% for alumina and about 40% for calcium carbonate. Judging from the electronegativity proposed by Linus Pauling, silica tends to form covalent bond with silanol group of silane. This is the reason why the adsorption of silica is highest. The amino group of silane adsorbs to the hydroxy group on inorganic particle surface by an ionic interaction. An ionic interaction occurs easily in order of calcium carbonate > alumina > silica. For this reason, the adsorption increased for amino functional silane, and it was more remarkable for calcium carbonate and alumina.

Dismantlable adhesion as the on-demand dismounting technology attracted attention in various applications in order to save resources and energies. The adhesion properties of dismantlable adhesive materials are required to instantaneously change in response to any external stimulus as the trigger for dismantling. In this comprehensive paper, we reported dismantlable adhesion systems using linear and network polyperoxides containing peroxy bonds in the main-chain repeating units or in the crosslinking points, as well as the acrylate block copolymers containing reactive side groups, which were responsible to photoirradiation and the postbaking. The dismantlable adhesion using the polyperoxides was responsive to heat or UV irradiation and showed a drastic change in the adhesion properties. We further developed a dual-locked adhesion system consisting of two kinds of triggers for dismounting in order to avoid the trade-off relationship of stability during use and high sensitivity to stimuli upon dismantling. We demonstrated the validity of the dual-locked adhesion system using acrylate block copolymers as the pressure-sensitive adhesive materials in the presence of a photochemical acid generator. We also reported the synthesis of high-molecular-weight acrylate block copolymers as the high-performance dismantlable adhesives using an organotellurium-mediated living radical polymerization.