菠萝叶短纤维补强天然橡胶复合材料的研究

【作者】 李银环；

【导师】 黄茂芳； 谭海生；

【作者基本信息】 华南热带农业大学 ， 农产品加工及贮藏工程， 2004， 硕士

【摘要】 本文用菠萝叶短纤维(PALF)对天然橡胶(NR)进行补强，得到了综合性能优良的复合材料。对菠萝叶纤维进行了碱处理，用红外和热分析方法对处理前后的菠萝叶纤维进行了分析。研究了短纤维用量、纤维取向和不同粘合体系对PALF／NR复合材料力学性能的影响。用橡胶加工分析仪(RPA)、动态力学热分析(DMA)、同步热分析(STA)方法研究了菠萝叶短纤维／天然橡胶复合材料的加工流变性能、动态力学性能、玻璃化转变和热稳定性。结果表明：碱处理后纤维的结晶度和热稳定性得到提高；PALF／NR复合材料混炼胶的粘度随菠萝叶短纤维用量增加而增大，不易混炼均匀；随着短纤维用量的增加，复合材料的模量、硬度、定伸应力、撕裂强度增大；经RH粘合体系和天甲胶乳处理过的PALF／NR复合材料力学性能得到显著提高。菠萝叶纤维质量用量达到30％时，复合材料的应力～应变过程出现屈服点，材料表现出脆性。复合材料的玻璃化转变温度(Tg)随纤维用量增加而增大。复合材料的力学内耗(Tan δ)在较低温度(—80℃～10℃)范围，随纤维用量增加而减小，而在较高温度(60℃～130℃)范围，复合材料的Tanδ则随短纤维用量增加而增大；RH粘合体系与天甲胶乳粘合处理的复合材料，比未处理体系的Tanδ值小；短纤维在平行取向方向的天然橡胶复合材料Tanδ要大于垂直取向方向。天然橡胶和PALF／NR复合材料的DSC谱图显示两个明显的放热峰，而TG谱图表明天然橡胶与复合材料的主要失重峰都在300℃～400℃。更多还原

【Abstract】 Study on the pineapple leaf fiber reinforced natural rubber compositePineapple leaf fiber (PALF) reinforced natural rubber (NR) composite was carried out, which have good mechanical properties. The PALF was treated with alkali (NaOH) solution. The raw PALF and alkali PALF were analyzed with IR and STA. The effects of fiber loading, fiber orientation and fiber treatmet on the mechanical properties were studied . The RPA , DMA and STA were used to study the composite’s rheology properties, dynamic mechanical properties, glass transition and thermal properties.The alkali PALF fibers were more steady than the raw PALF fibers. The viscosity of the composites increased according to the fiber loading, therefore the composite with more fibers were difficult to milling. The composite’s normal mechanical properties, such as hardness, modulus, tensile strength, tear strength were found to increase by the introduction of fiber. The RH and MG latex adhesion systems make the composite have better properties. When the fibers in the composite is more than 30% there is a yield point in the stress-strain curve. The composite’s glass transition point (Tg) increased with the fiber content.In a lower temperature range (-80 - 10) , the mechanical loss factor (Tan 8 ) of the composite reduced when fiber content is more. In a higher temperature range (60~130), Tan 6 increased with increasing fiber. The RH system composite and MG adhesion composite have a lower Tan 8 than the untreated composite. In different fiber orientations, Tan 8 of parallel composite is higher than that of vertical. There are two radiative peaks in the DSC curves of NR and PALF/NR composite. The main weight loss in TG pictures are in 300 400.更多还原