Preparation of a new class of organic/inorganic polymer hybrid (nano glass) (3) from novolac (1) is described. 3 was prepared by the acid-catalyzed sol-gel reaction of phenyltrimethoxysilane (PhTMOS) ...(2) in the presence of 1. 3 was transparent film and showed high heat stability. The dispersion of two components was the utilization of π-π interaction between phenyl ring of silica matrix and that of novolac.
This article describes the preparation of a functional novolac having electron withdrawing groups (nitro groups) by a polymer reaction of a novolac derivative. o-t-Buthylphenol novolac (a precursor) ...(2) was prepared by the HCl-catalyzed addition-condensation of o-t-buthylphenol with paraformaldehyde in a good yield. Then 2 was regioselectively into o-nitrophenol novolac (3) in good conversion. The structure of 3 was confirmed by IR, lH NMR and GPC analysises, and the property was well-soluble in common organic solvents but insoluble in hexane and water. 3 is expected as an explosive material and a biofunctional polymer.
We investigated the characteristics of a decellularized porcine cornea by ultra-high hydrostatical pressurization (UHP) method. The UHP method consists of the disruption of cells by hydrostatical ...pressurization and the removal of components of the disrupted cells by washing process. Porcine cornea were hydrostatically pressed at 10,000 atmospheres and 10 °C for 10 min and immersed in medium for 72 hours. The turbid cornea was obtained. For H-E staining of the cornea decellularized with the UHP method, the complete removal of corneal cells and maintenance of the superstructure of collagen fibrils were confirmed. When the corneas were immersed in glycerol for 1 hour, their optical and mechanical properties were restored to those of a natural cornea. As the preliminary animal study, when the implantation of the acellular porcine cornea to rabbit cornea was carried out, the immune reaction was not occurred and the turbid cornea became clear. These results indicate that the decellularized cornea by UHP method would be useful as corneal scaffold for regeneration. These results indicate the possibility of the acellular cornea prepared by the UHP method as artificial bio-cornea.
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