熱壓溫度與時間對合板膠合層形態與性質之影響

本研究之目的在探討不同之熱壓壓力與時間下，膠合層之溫度上升情況與其型態上之變化對製造柳桉合板性質之影響及印證前人之熱壓理論。由試驗結果得知，在熱板125℃之溫度、不同熱壓壓力8及12 kgf/cm^2與熱壓時間8、10、15及20 sec/mm，所測得之膠合層最高溫度除對照組外，均達足使尿素膠硬化之110℃以上；合板的膠合強度除對照組中層溫度未達90℃者外，亦均達CNS1349普通合板二類合板之合格標準。經由光學顯徵鏡觀察各條件製板之膠合層的氣泡形態之結果，可知膠合層溫度在熱壓中若超過水之沸點以上，各種條件製板之膠合層均有氣泡存在；若在水之沸點以下之製板溫度（90℃）條件下，則有半數之膠合層有氣泡，顯示在一般的製板條件下，存在膠合層之氣泡，部分是來自膠合劑之塗佈作業，另一部分則是膠合層達到水之沸點時，水沸騰在膠合層內產生之氣泡。

關鍵字

尿素甲醛樹脂膠合劑；合板

並列摘要

The purpose of this study was threefold. The first one was to investigate the relationship between the final glue line temperature and its morphology of plywood under various manufacturing conditions. Secondary was to reveal the effect of the final glue line temperature on the bonding properties of plywood. And the thirdly was to test the validity of the hypothesis of the previous hot pressing theory. From the experimental results, all the final glue line temperatures under various conditions (except the controlled ones) of pressure (8 and 12 kgf/cm^2) , press temperature 125℃ and press time (8, 10, 15 and 20 sec.lrom) were over 110℃ sufficient to set UF glue. The bonding properties of plywood could meet the type II requirements as specified by CNS1349. From the observations of glue line morphology, air bubbles existed in all the glue lines. If the glue line temperature over the boiling point of water, air bubbles existed in glue line inevitably. For the control one, the glue line temperature only raised to 90℃, air bubbles existed in half of the glue line. The reason was that air bubbles were formed by glue spreader. Therefore, the conclusion we made was that air bubbles existed in the glue lines were formed by water boiling or by glue spreading.

並列關鍵字

UF glue ； Plywood

國際替代計量

熱壓溫度與時間對合板膠合層形態與性質之影響

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