Bamboo flour was used as a filler in the manufacture of bamboo flour-plastic composites. The properties of bamboo flour-plastic composites with 80% filler contents were examined using waste bamboo flour, polypropylene (PP), and maleic anhydride-modified polypropylene (MAPP) and/or polytetrafluoroethylene (PTFE). The compounds could be successfully manufactured using a Henschel type mixer, and then the composite boards were made by compression molding and extrusion molding. The composite boards made from both moldings showed good fracture strengths and water resistance by the addition of compatibilizer. The mechanical properties of boards made with extrusion molding and a ratio of bamboo flour: PP: MAPP=80: 20: 2 were bending fracture strength; 74MPa, and water absorption (WA) after 24hr immersion in water; 1.5%. The color of composites darkened with the addition of an additive. The addition of PTFE significantly increased luster and smoothness of the appearances of the composite boards.

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The purpose of this study is to clarify the durability of the adhesion joint in a real steel structure and to establish a method of the estimation of its durability. At first, we estimated the lifetime of adhesion joints used for houses that were really built 10, 15 and 20 years ago. However, we had no samples prepared from adhesion joints used for houses that were really built more than 20 years ago, so we had to estimate the lifetime of adhesion joints over 20 years by another method. We showed a lifetime estimate method that is estimated by using an appropriate coefficient of degradation promotion obtained from comparing degradation promotion test results with evaluation results of adhesion joints of houses that were really built. In this method, the degradation promotion condition must be highly correlated to a real environmental condition and the destruction mode of both tests was always cohesive destruction.From this method, we were able to prove that this adhesion joint had over 90 years durability that was necessary for long-lifehouses.

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Multi-component random copolypeptides consisting of N-hydroxyethyl-L-glutamine, L-glutamicacid, and L-lysine were prepared by aminolysis with aminoalcohols, such as 2-amino-1-ethanol (E) and 5-amino-1-pentanol (Pe), followed by crosslinking with octamethylene diamine (OMDA). The effective crosslink density was proportional to the content of OMDA in the reaction mixture. The tensile properties of these hydrophilic membranes (hydrogels) were highly dependent on the swelling ratio q in the pseudo-extracellular fluid PECF, hydrophobicity of the side chains, and the effective charge density of hydrogels. Their mechanical behavior was similar to that of elastomer. Biodegradation of the membranes in vitro by bromelain indicated that the degradation took place through the bulk phase of the hydrogels not only the surface region. The rate of degradation was also highly dependent on the swelling ratio q of hydogel, as well as on the hydrophobicity and effective chatge density of side chains of copolypeptides.

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