熱處理過程中桉木水溶性抽提物遷移對材色的影響1)

馬姍姍 陳瑤 高建民

(木質(zhì)材料科學(xué)與應(yīng)用教育部重點(diǎn)實(shí)驗(yàn)室(北京林業(yè)大學(xué))，北京，100083)

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熱處理過程中桉木水溶性抽提物遷移對材色的影響1)

馬姍姍 陳瑤 高建民

(木質(zhì)材料科學(xué)與應(yīng)用教育部重點(diǎn)實(shí)驗(yàn)室(北京林業(yè)大學(xué))，北京，100083)

為探討桉木水溶性抽提物組分在熱處理過程中遷移對材色的影響，對桉木弦切板試件進(jìn)行熱水抽提去除水溶性抽提物；然后在不同的溫度和時(shí)間條件下，對去除水溶性抽提物的桉木試件進(jìn)行抽提物遷移實(shí)驗(yàn)，分析不同時(shí)間和溫度下抽提物在木材徑向的遷移距離及遷移量，以及水溶性抽提物遷移對木材顏色的影響。研究表明：溫度越高，抽提物遷移的速度越快；抽提物的遷移距離隨時(shí)間延長而增加，在100 ℃，加熱4 h時(shí)達(dá)到最大值51 mm。抽提物分子極性不同，與木材其它組分的吸附性能各異，在80 ℃下抽提物在木材中隨水分的遷移比較均勻。抽提物在木材內(nèi)的吸附隨時(shí)間的延長趨于穩(wěn)定狀態(tài)。隨著水溶性抽提物的遷移，木材的顏色加深，促進(jìn)了木材紋理間顏色趨于均勻。

桉木；熱處理；水溶性抽提物；遷移；木材顏色

The experiment was conducted to study the effect of moving of water-soluble extractives in Eucalyptus on wood color during heat treatment by using the tangential timber ofEucalyptus. The water-soluble extractives moving experiment was conducted under different temperature and duration, the speed and amount of water-soluble extractives moving along with radical orientation at different temperatures and duration was evaluated, and the effect of extractives moving on wood color changes was also analyzed. The speed of extractives moving was increased with temperature increasing, the amount of extractives moving was increased with treated duration, and the moving distance reached 51 mm when heated for 4 h at 100 ℃. The moving and adsorption of the water-soluble extractives was stable when heat treated at 80 ℃, due to the different molecular polarity and adsorption performance. The adsorption of the extractives tended to be stable with the increasing of treatment time. Wood color was darkened and uniformed with the moving of extractives.

木材顏色是木材表面性質(zhì)、木材品質(zhì)和利用價(jià)值評定的重要指標(biāo)，是木材產(chǎn)品加工增值的重要影響因子，是決定消費(fèi)者選擇的重要因素[1]。木材在生長過程中因早、晚材和心、邊材而顏色不均，一定程度上限制了木材的利用范圍。通過熱處理提高木材顏色均一性是現(xiàn)代企業(yè)提高木材經(jīng)濟(jì)價(jià)值最易實(shí)現(xiàn)、最有效的方法之一，已受到木材加工利用領(lǐng)域的廣泛關(guān)注。……