The crosslinked polyolefin foams of poly(ethylene-co-vinyl acetate) (EVA)/olefin block copolymer (OBC)/ clay nanocomposite were prepared to examine the effect of clay on the properties of the foam. The dispersed clay reduced the foam cell size and enhanced the expansion of the foam by nucleating effect. In addition, the gel content of the foam was increased, and the mechanical properties, such as modulus, tensile strength, and elongation at break, were improved by added clay. The dispersed clay reduced the polymer chain mobility and thus the tan δ peak height at glass transition temperature decreased and the peak extended to higher temperature region. The rebound resilence, sound absorption coefficient, and the ideal rubber elasticity exhibited at rubbery plateau were also reduced by the clay dispersed in the foam because of the restricted chain mobility of the matrix polymer.

The ethylene-propylene-diene monomer rubbers (EPDMs) were examined as crosslinking promoters in the preparation of crosslinked foams of olefin block copolymer (OBC) and ethylene-vinyl acetate copolymer (EVA) blends. The gel content of the crosslinked foam was increased as the amount of EPDM added into the blend was increased, which showed that the EPDM effectively did a role as a crosslinking promoter. This enhanced crosslinking induced the increases of density and modulus, and the decrease of foam cell size. In addition, the EPDM enhanced the compatibility between OBC and EVA, which made the foam cell size more uniform. However, the increased crosslinking and enhanced compatibility by EPDM reduced the crystallinities of both OBC and EVA.

Objectives Community-centered youth education that develops the ability to solve problems in the local community is of great importance for the youth who must live in the era of the new normal after the pandemic. Therefore, this study intends to reveal how convergence thinking in architecture can play a role in the education of youth in the local community and what its limitations and possibilities are through a review of ‘2021 Jeju Youth Architecture School’. Methods First, a theoretical review was conducted on community-centered youth education and architecture education, which were the theoretical backgrounds for the development of the Jeju Youth Architecture School program. Next, the characteristics of the proposed program (educational subject, curriculum, educational content, etc.) were considered. Finally, the limitations and possibilities of the program were considered through analysis and evaluation of the results of the youth architecture school. Results As the educational goals of the program, ‘sociality’ to understand the social roles and responsibilities of architects, ‘creativity’ to understand how ideas are built into architectural spaces, and ‘locality’ to seek a role as a member of the community were shared. In order to realize the educational goals, the program could be divided into three stages: ‘value sharing, goal setting, suggestion and evaluation’. As a result of the evaluation, the architect's new role (sociality) and creative architectural alternatives (creativity) were highly evaluated for a clear social phenomenon called the corona pandemic. On the other hand, it could be revealed that the results of concerns about the region (locality) due to the rigidity caused by the corona were not relatively well evaluated. Conclusions ‘2021 Jeju Youth Architecture School’ was able to reveal that it has the characteristics of community-centered youth architecture education, such as developing a cooperative system and developing educational goals and programs among various local actors. In addition, it was confirmed that education using local resources can contribute to the discovery and resolution of social problems and the expression of creativity among young people.

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