It is necessary to establish the design standard of adhesively bonded joints because adhesion is not recognized as a general joining method. Therefore, a method for obtaining the specified design strength and allowable design strength of a joint is proposed. In this proposal, (1) temperature dependency of strength, (2) strength dispersion, (3) internal failure and (4) deterioration are considered as a decrease factor of strength for adhesive bonding. Specified design strength is calculated by the proposal method. As a result, specified design strength is estimated as 1/13-1/27 of the initial lowest average strength in the application temperature range. When the safety factor is 1.5 times, allowable design strength is 1/20-1/40.

The influence of filler diameter on the impact strength of PP/elastomer/filler ternary composite was investigated, controlling these impact fracture behavior from brittle to ductile by changing the volume contents of the elastomer.In the case of pure PP -without elastomer content- that shows brittle fracture, the impact strengths were increased with adding all type of filler used in this study. In particular, the impact strength was increased significantly in the case of filler with a diameter of 0.12mm used. In the case of PP/elastomer composite, showing ductile fracture behavior in the polymer phase, the impact strengths of the composites were significantly increased by using fillers with diameters below 2.5mm, while with diameters above 3.0mm, the impact strengths were decreased.These results indicate that impact strength change of the composite by the influence of filler depends on both the filler diameter and the impact fracture behavior of the polymer phase.

Although standard measurement methods for tack, peel strength, creep performance are important for the quality control on manufacture and business of pressure sensitive adhesion (PSA), scientific approach on evaluation of PSA performance are necessary for development of PSA. For rolling ball tack, evaluation method by rolling friction coefficient was proposed in spite of ball number on business. For probe tack, the rate of increase of effective contact area is described by a 4th order rate equation. Cylinder tack measurement method on wide velocity and temperature was established and master curve of the data measured by the method was got by using the time (or velocity)-temperature superposition procedure. Calculations of cylinder tack (rolling friction coefficient) based on two Maxwell elements in parallel model agreed with experimental data measured using several kinds of cylinder which has different critical surface tension value.