The higher-order structure of natural rubbers which were crosslinked by peroxide or sulfur were analyzed by 1H pulsed NMR. The relaxation spectrum was obtained as a relationship of relaxation time and component by applying the Gaussian expansion to the spin-spin relaxation decay. The difference between the structures could be viewed clearly by the NMR measurements of samples that were swollen by deuterated toluene. The deficient component with active molecular mobility existed much more in peroxide-crosslinked NR than sulfur-crosslinked one. Therefore, it was estimated that the tensile strength of peroxide-crosslinked NR was lower than that of sulfur-crosslinked one. Improvement in the tensile properties due to filling of the carbon black was more pronounced in peroxide-crosslinked system than sulfur-crosslinked system. The filling of carbonblack resulted in a decrease of deficient component in the relaxation spectrum for peroxide-crosslinked NR. The shape of spectra of peroxide-crosslinked NR became similar to that of the sulfur-crosslinked NR with the filling of carbon black.

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In this study emission from wood-based materials specimen glued with both Epoxy resin adhesives(EP) and Ethylene-Vinylacetate copolymer emulsion adhesives (EVA) contained a slight amount of toluene, xylene, ethylbenzene was measured by using small chamber method according to JIS A 1901. The result of this study,show that it has been understood that the VOC's emission changes due to an internal structure and　 components characteristic. After 1day the VOC of MDF specimen and PB specimen decreased slightly. Their reason is that the MDF specimen and PB specimen are porous wood-material. Similar VOC's emission behavior was achived by CSB specimen and MDF specimen. VOC's emission behavior of PW specimen decreace gradual.It is suggest that the cause depends on PW adhesion layer.

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