竹原纤维增强石膏板性能研究

The Properties of Gypsum Board Reinforced by Bamboo Fiber

研究采用润湿处理、NaOH处理和硅烷偶联剂KH550(γ-氨丙基三乙基氧基硅烷)处理等方式改性竹原纤维(长度为20 mm),并将竹原纤维用于增强石膏板。对竹原纤维/石膏复合材的静曲强度、弯曲模量、吸水厚度膨胀率及内结合强度进行测试,采用傅里叶红外光谱、扫描电子显微镜和X射线扫描分析手段探究增强原理。竹原纤维经处理后制备的复合材脆性减小、结晶度增大、力学性能都有提高,脆性得到改善。NaOH处理去除了纤维表面的蜡质等,使表面粗糙;偶联剂处理降低了纤维表面的极性,这些都有利于改善纤维与石膏的界面结合,提高石膏板的力学性能。当竹原纤维质量分数为3%时,复合材的静曲强度比纯石膏提高了77.8%,弯曲模量提高了9.4%,内结合强度提高了229.6%,24 h吸水厚度膨胀率未发生明显变化。

In this paper,the bamboo fibers were modified by wetting,NaOH and silane coupling agent(3-Aminopropyltriethoxysilane)treatment.These fibers were used to reinforce gypsum board.The static bending strength,flexural modulus,water absorption,thickness expansion ratio and the internal bonding strength of the composites were tested.The composite was subjected to Fourier transform infrared spectroscopy,micromorphology analysis and X-ray diffraction analysis.The results showed that all three treatments could improve the mechanical properties of the gypsum board and the NaOH treatment achieved the greatest improvement.The NaOH treatment removed the waxy substances on fiber surface and coupling agent reduced the polarity of fiber surface,which benefited to the interface bonding between bamboo fibers and gypsum.Comparing to pure gypsum board,when bamboo fiber fraction amounted to 3%,the static bending strength,flexural modulus,internal bonding strength of the fiber reinforced gypsum composite were increased by 77.8%,9.4%and 229.6%respectively.Its thickness swelling rate due to water absorption was almost unaffected.Treatment to fiber surface also increased in the crystalline and toughness of gypsum board.