为了研究人造板板坯的导热性能,采用准稳态平板法,测试了木材纤维和稻草刨花两种板坯在载胶状态下(UF树脂施加量为10 %,以绝干纤维或刨花为基础)的导热系数,研究了试验板坯目标密度(0.6、0.7、0.8和0.9 g/cm3)和含水率(木材纤维:10 %、15 %、20 %、25 %和30 %;稻草碎料:10 %、15 %和20 %)对板坯导热系数的影响。结果表明:在试验目标密度和含水率条件下,木材纤维板和稻草刨花板板坯的导热系数分别为0.231 5~0.523 6 W/(m〖DK〗·K)和0.260 4~0.344 6 W/(m〖DK〗·K);板坯导热系数随密度增大和含水率提高而递增,含水率对木材纤维板板坯导热性能的影响比对稻草板板坯的显著;在板坯含水率低于20 %时,稻草板板坯的导热性能普遍优于木材纤维板板坯。
Abstract
To disclose the heat conduction property of woody composite mat, quasi steady state method was applied to test the heat conduction coefficient (HCC) of wood fiber and rice straw particle motrice with 10 % liquid urea formaldehyde (UF) resin based on ovendry fiber or particle at room temperature in this paper. Influences of processing parameters, including designed board density (0.6, 0.7, 0.8, and 0.9 g/cm3) and mat moisture content (10 %, 15 %, 20 %, 25 %, 30 % for wood fiber mat (WFM), and 10 %, 15 %, 20 % for rice straw particle mat (RPM)), on HCC were studied. Test results showed that under above conditions: (1) HCC of WFM and RPM were 0231 5-0.523 6 W/(m〖DK〗·K) and 0.260 4-0.344 6W/(m〖DK〗·K), respectively; (2) HCC of both mats increased with increased designed board density and/or higher mat moisture content (MC), and MC showed stronger significance on HCC of WFM than that of RPM; (3) RPM showed overwhelmingly higher HCCs than WFM with MC under 20 %.
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基金
收稿日期:2011-05-11修回日期:2011-09-27基金项目:江苏省苏北科技计划项目(BC2009476);江苏高校优势学科建设工程资助项目第一作者:徐信武,副教授,博士。Email: xucarpenter@yahoo.com.cn。