木材接着に関する研究(第7報) : 熱帯産木材の接着性について(その2)

The effects of various properties on the gluability of tropical woods have been investigated.
The tropical woods of 36 species which were used in the previous paper were glued with urea-(UF) and phenol-formaldehyde resin adhesive(PF). Glued woods were tested for block shear strength in air dried condition. The glue-joint strength and wood failure are shown in Table 1.
The coefficient of correlation between gluability (glue-joint strength and wood failure) and various properties(specific gravity, pH, extract with ether and wettability) was calculated. Then the regression line was yielded by regression analysis only when a significant correlation at five percent level or better was recognized. If the correlation was not significant, it was not shown or a horizontal line was through the mean value. The results of analysis are presented in Fig. 1-7.
The correlation between gluability and various properties revealed the trend of dependent variable at 0.8 specific gravity. The following conclusions may be drawn from the results of the analysis.
<tt>
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S. G. | below 0.8 | above 0.8
-------------|-----------------|-----------------
G. S.-S. G. | S(UF. PF) | NS
W. -S. G. | NS | S(UF, PF)
S. G. S.-E. | S(UF) | NS
S. G. S.-C. | S(UF, PF) | NS
W.-C. | S.(PF) | NS
S. G. S.-Ic. | S.(UF) | NS
W.-Ic. | NS | S(UF)
W.-Dc.(urea) | NS | S(UF)
-------------------------------------------------
</tt>
S. G.:specific gravity. E.:extract with ether, C.: C. W. A. H.,
Ic.:cosine of contact angle (inclined plate method),
Dc.:cosine of contact angle (droplet method),
G. S.:glue-joint strength. S. G. S.:specific glue-joint strength (glue-joint
strength/specific gravity),
W.:wood failure
S:significant, (5% level) NS :not significant (50% level)