【作者】 熊雅；

【导师】 叶菁；

【作者基本信息】 武汉理工大学 ， 材料学， 2012， 硕士

【摘要】 透闪石是一种纤维状硅酸盐矿物材料,作为低温快烧节能原料主要应用于陶瓷行业。但相关研究表明,具有一定长径比的矿物纤维对聚合物材料有增强作用,可以改善聚合物的力学性能。本文研究了一种松解法制备高长径比透闪石纤维,并通过表面改性处理,对PP树脂进行透闪石纤维填充实验,力学性能测试表明,松解法制备的透闪石纤维对树脂具有填充增强效果。通过对透闪石的松解研究发现,酸处理、表面活性剂,以及机械粉碎施力方式对透闪石长径比和单体纤维含量有显著影响。其中,具有渗透、分散作用的磷酸三钠、亚甲基二萘磺酸钠和十六烷基三甲基溴化铵等表面活性剂有利于透闪石的松解,且亚甲基二萘磺酸钠的效果最好；在粉碎施力方式中,以湿法剪切力为主的胶体磨具有很好的松解效果,而以碰撞、冲击为主要施力方式的其它干法磨机不利于透闪石晶型保护；而稀酸可以在一定程度上弱化纤维间的结合力,有助于透闪石的松解。通过表面活性剂种类、分散设备选择及松解工艺的优化实验,制备出的透闪石纤维长径比达到46.9,单体纤维含量为69%。通过对透闪石纤维的表面改性研究发现,硅烷偶联剂在活化度、沉降体积和粘度方面表现出较好的改性效果,且用量在1.2%时效果最佳。经红外和热分析发现,透闪石表面的羟基与硅烷偶联剂的硅醇基形成硅氧烷键,表明硅烷偶联剂与透闪石纤维表面发生了化学吸附,且硅烷偶联剂的化学吸附量为1.0%。通过透闪石纤维在PP中的填充研究发现,未改性的透闪石/PP复合材料的缺口冲击强度略有下降,但拉伸强度和弯曲强度有所提高；而改性后透闪石/PP复合材料的拉伸强度、缺口冲击强度和弯曲强度均有提高。当透闪石纤维填充量为20%时,与纯PP相比,透闪石/PP复合材料的拉伸强度提高了21.2%,缺口冲击强度提高了7.5%,弯曲强度提高了51.4%。最后,经与表面改性CaCO3填充PP的对比实验可知,在相同填充量下,透闪石／PP复合材料的拉伸强度、缺口冲击强度和弯曲强度均高于CaCO3/PP复合材料。更多还原

【Abstract】 Tremolite is a kind of fibrous silicate mineral material, and it is mainly used in ceramic industry as a fast firing energy saving materials at low temperature. But some researchs show that, mineral fiber with certain length diameter ratio has enhancement function to polymer material,it can improve the mechanical properties of polymer. This paper studies a method of dispersion to prepare tremolite fibers, then we modify its surface and fill it into polypropylene resin. Mechanical property tests show that, the tremolite fibers have enhancement effect to polypropylene resin.The releasable study of tremolite find that acid treatment, surface active agent, and the motheds of mechanical force application have significant influence on the length diameter ratio of tremolite fibers and single fiber content. Because of their osmosis and dispersant effect, Na3PO4, NNO and CTAB are beneficial to the debonding of tremolite fibers, and the NNO has the best effect. Among the breaking plants, colloid mill with wet shear force has good defiberization effect, and other dry mill with striking force and impact force are not suited to protect the crystal form of tremolite; and the dilute acid can weaken the bonding between the fibers to a certain degree, which contributes to the release of tremolite. Through the optimizing experiments of the variety of surfactant, dispersion equipment selection and releasable technology, the prepared tremolite fiber’s length diameter ratio reach46.9, and the single fiber content is69%.The surface modification research of tremolite fibers show that silane coupling agent exerts good modification effect on active ratio, sedimentation volume and viscosity, and the effect is best when the usage is1.2%. Infrared and thermal analysis results show that hydroxyl group on the surface of tremolite and silanol of silane coupling agent form siloxane bonds, which indicate that there is a chemical reaction of silane coupling agent with tremolite fibers surface, and the chemical adsorption quantity of silane coupling agent is1.0%.The mechanical property research of PP filled with tremolite fibers show that the notch impact strength of un-modified tremolite/PP composite decrease slightly, but the tensile strength and bending strength increase. And the modified tremolite/PP composite in the tensile strength, notched impact strength and bending strength are improved. When the loading level of tremolite fibers is20%, compared with pure PP, tremolite/PP composite’s tensile strength is increased by21.2%, notched impact strength increased by7.5%, and bending strength increased by51.4%. The mechanical property research of PP filled with tremolite and CaCO3whose sueface is modified show that at the sameloading level tremolite/PP composites’s tensile strength, impact strength and bending strength are higher than those of CaCO3/PP composites.更多还原