頁籤選單縮合
題名 | 三種省產闊葉樹材與聚胺基甲酸脂塗料及硝化棉塗料塗膜之水氣透過性探討 |
---|---|
作者姓名(中文) | 王松永; 劉磊; | 書刊名 | 國立臺灣大學農學院研究報告 |
卷期 | 31:1 1991.03[民80.03] |
頁次 | 頁1-17 |
分類號 | 436.18 |
關鍵詞 | 水氣; 省產; 透過性; 硝化棉; 塗料; 塗膜; 聚胺基甲酸脂; 闊葉樹材; |
語文 | 中文(Chinese) |
中文摘要 | 本研究係探討三種省產闊葉樹材與聚胺基甲酸脂塗料(PU)及硝化棉塗 料(NC)兩種塗膜,在31.8℃,40℃及50℃三種溫度條件下之水氣透過性,而其相 對濕度係固定為30,得次述結果: 1.未塗裝材(軸向與徑向)與PL及NC單離塗膜之水氣透過性皆隨溫度增加而增大。 2.木材之軸向水氣通透主要以導管為主,本實驗以長尾尖儲之水氣透過性最大, 因其具有最大之導管平均直徑與佔有率。而徑向之水氣透過性主要以木質線組織 為主,本實驗亦以長尾尖儲最大,因其具有最大的木質線組織。 3.木材之比重因子會影響水氣的擴散係數,而以長尾尖儲之比重最小,故得到最 大擴散係數。 4.以不同厚度木材進行水氣透過性試驗得知,厚度增加使透過量降低,但其擴散 係數卻增加。如表3所示。 5.PU塗膜之水氣透過性略小於硝化棉塗膜,而其水氣透過量之對數略會隨塗膜厚 度之對數增加而減低。其關係可以式(11)~(16)表示。 6.木材塗裝兩種塗料後會使水氣透過性降低,但塗佈後,樹種間水氣透過量大小 趨勢不變。 7.本實驗各樹種之軸向與徑向的擴散係數之對數(log D)會隨其絕對溫度之倒數 (1/T。K)增加而呈直線狀減低,如圖1~6所示。 |
英文摘要 | The main purpose of this study was to investigate the water vaporpermeability of polyurethane (PU) resin and nitrocellulose (NC) lacquer filmof three Taiwan native hardwood species, the steady state method was used.Observations were based on constant relative humidity (RH= 30), butvariable temperature (31.8 ℃ 、 40℃ 、 50℃). The results are summarized asfollows: 1. Vapor movement along the axial and radial directions of uncoated wood, as well as along the thin free film of the two coatings, increased with higher temperature. 2. Vapor movement was facilited by the presence of vessels and ray tissues. Because the wood from Castasiopsis carJessi Hay. contained the largest vassels and ray tissues, it had the greatest diffusion coefficient. 3. Diffusion coefficient was negatively correlated with density of wood. Among the tree species, Castanopsis carlesii Hay. had the lowest density, hence, the highest diffusion coefficient. 4. Vapor permeability was negatively correlated with "the thickness of wood block, However, the thicker the block, the higher the diffusion coefficient was as shown in Table 3. 5. Water vapor permeability was lower in PU resin film than that in NC- lacquer. The logarithm of permeability was negatively correlated with the logarithm of thickness of coated free films. Their relationships can be described by regressions(11)~(16) 。 6. Permeability was lower with coated woods. The trend of variation in the amount of vapor movement remained unchanged in three wood species. 7. The logarithm of the axial diffusion coefficient and the radial diffusion coefficient is negatively correlated with the inverse of the absolute temperature. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。