Polyhydroxyalkanoates (PHAs) incorporating vinyl-bearing 3-hydroxyalkanoates were prepared in 8.5-12.9 g·L -1 yield. The molar ratios (0-16 mol%) of the vinyl-bearing 3-hydroxyalkanoate derivatives were controlled by the continuous feeding of undecylenate at various concentrations. Subsequently, the PHAs were functionalized by UV-initiated thiolene click reaction and chemical modification. 1 H NMR spectra suggested that 3-mercaptopropionic acid and 2-aminoethanthiol were successfully introduced into the vinylbearing PHA. Subsequently, chemical modification using fluorescein or a fibronectin active fragment (GRGDS) was attempted. The former yielded a PHA derivative capable of emitting fluorescence under UV irradiation, which was useful for determining the miscibility of PHA in a composite film comprising poly-ʟ-lactic acid (PLLA) and PHA. In the latter case, PHA bearing GRGDS peptides exhibited cell adhesiveness, suggesting that its biocompatibility was improved upon peptide introduction. Taken together, the UV-initiated thiol-ene click reaction was demonstrated to be useful in PHA modification.

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The objective of this study is to simulate the shaking test of a condensate storage tank (CST). In this test, the typical failure mode was an elephant-foot bulge (EFB) or a shear buckling. It is difficult to reproduce such buckling modes. However, at last, an analytical model which describes those modes with enough accuracy was achieved. The comparison between simulation results and experiments is explained. Acoustic theory and classical plasticity theory were used in the FEM simulation. The phase and magnitude of the response acceleration and hydraulic pressure obtained from the FEM simulation are well corresponded to those from the experiments. In addition, asymmetrical distribution of maximum and minimum hydraulic pressure is described.

Rubber-like materials have strong nonlinearities in dynamic and static stiffness and damping characteristics. To confirm all of the nonlinearities of rubber material, a large number of tests must be carried out. Therefore, an evaluation method by which stiffness and damping characteristics including several nonlinearities of rubber element can be estimated by a few kinds of material tests would be greatly useful. The purpose of this study is to establish an evaluation method in which the nonlinearities of rubber-like material caused by loads simultaneously applied in both the shear and compression directions are taken into consideration. As the first step of this study, a material stretch test, a static load test and an FEM analysis were carried out to determine the nonlinear characteristics of static stiffness caused by loads applied in both the compression and shear directions. The method proposed in this paper for correcting material parameters on the basis of the strain level of the rubber was verified to be useful for accurate estimation of nonlinear stiffness. It was verified that the dependency of the static stiffness on the initial deformation can be expressed by the FEM analysis and the proposed method can precisely estimate the nonlinear behavior of rubber isolators.

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