功能化氮化硼纳米片的制备及其高分子复合材料性能研究
发布时间：2018-11-20 08:59
【摘要】：六方氮化硼由于其独特的二维层状结构,优异的机械强度、导热性、电绝缘性、以及化学和热稳定性能,使其在增强聚合物性能方面具有广阔的应用前景。本论文将从氮化硼纳米片的制备以及氮化硼纳米片对聚乙烯醇、天然橡胶、聚丙烯酰胺水凝胶高分子复合材料性能的影响等方面进行研究,主要包括以下几个方面:1.通过高温、超声等处理成功制备了功能化的氮化硼纳米片,并利用傅里叶红外光谱(FTIR)、X射线衍射(XRD)、透射电子显微镜(TEM)和拉曼光谱(Laman)对功能化氮化硼纳米片的结构和形貌进行表征。结果表明此法可以制备出晶型结构完整、尺寸较大且层数较少的氮化硼纳米片。纳米片上存在着大量的羟基,有利于进一步功能化。2.以功能化氮化硼纳米片和聚乙烯醇为原料,通过溶液共混法制备了一系列不同含量的氮化硼纳米片/聚乙烯醇复合材料。并进行了FTIR、XRD、扫描电子显微镜(SEM)、差示扫描量热(DSC)、热失重分析(TGA)、拉伸和动态力学性能(DMA)的测试分析。结果表明纳米片均匀的分散在聚合物中,没有出现明显的团聚现象,纳米片还与聚乙烯醇基体之间存在着氢键的相互作用。少量氮化硼纳米片的加入,就可以提高聚合物的热学性能。静态力学和动态力学测试结果显示,加入1wt%的氮化硼纳米片,拉伸强度和储能模量分别提高了87.5%和43%,这说明氮化硼为聚合物优良的填料。3.以功能化氮化硼纳米片和天然胶乳为原料,利用胶乳共混,然后在甲酸溶液中共沉淀的方法制备了不同含量的氮化硼纳米片/天然橡胶复合材料。并对复合材料进行了XRD、SEM、DMA、拉伸和导热性能的测试分析。结果表明加入氮化硼纳米片后,复合材料的机械强度显著提高。本实验制备的一种类似于网状的特殊结构为热量传递提供了更多的途径,可以提高复合材料的导热性能,氮化硼添加量为5 wt%时,橡胶的导热率可达0.192 W m-1K-1明显高于纯样(0.152 W m-1K-1)。4.以聚丙烯酰胺、海藻酸钠、氮化硼纳米片为原料,制备了不同类型的(聚丙烯酰胺、氮化硼纳米片/聚丙烯酰胺、海藻酸钠/聚丙烯酰胺和氮化硼纳米片/海藻酸钠/聚丙烯酰胺)水凝胶,并对样品进行FTIR、SEM、DSC、拉伸和溶胀性能的测试。结果显示,三网络结构水凝胶比单网络聚乙烯醇水凝胶的结构更加致密。氮化硼纳米片以及新的离子交联网络会引起水凝胶拉伸强度和热性能的明显提高。与聚丙烯酰胺水凝胶相比,三网络水凝胶的最大降解温度能够提高12℃,拉伸强度提高963.6%,模量提高354%。
[Abstract]:Because of its unique two-dimensional layered structure, excellent mechanical strength, thermal conductivity, electrical insulation, and chemical and thermal stability, hexagonal boron nitride has a broad application prospect in enhancing polymer properties. In this paper, the preparation of boron nitride nanoparticles and the effects of boron nitride nanoparticles on the properties of polyvinyl alcohol, natural rubber and polyacrylamide hydrogel polymer composites are studied, including the following aspects: 1. The functionalized boron nitride nanocrystals were successfully prepared by high temperature and ultrasonic treatment. The (XRD), was diffracted by (FTIR), X ray by Fourier transform infrared spectroscopy (FTIR). The structure and morphology of functionalized boron nitride nanocrystals were characterized by transmission electron microscopy (TEM) (TEM) and Raman (Laman). The results show that boron nitride nanocrystals with large size and less layers can be prepared by this method. There are a large number of hydroxyl groups on the nanocrystals, which is conducive to further functionalization. 2. A series of boron nitride / polyvinyl alcohol composites with different contents were prepared by solution blending method using functional boron nitride nanoparticles and polyvinyl alcohol as raw materials. The FTIR,XRD, scanning electron microscope (SEM),) differential scanning calorimetry (DSC),) thermogravimetric analysis (TGA) was used to analyze the tensile properties of (TGA), and the dynamic mechanical properties (DMA). The results show that the nanoparticles are uniformly dispersed in the polymer, and there is no obvious agglomeration phenomenon, and there is a hydrogen bond interaction between the nanoparticles and the polyvinyl alcohol matrix. The thermal properties of the polymer can be improved by adding a small amount of boron nitride nanoparticles. The results of static and dynamic mechanical tests showed that the tensile strength and storage modulus of boron nitride nanocrystals increased by 87.5% and 43% respectively, which indicated that boron nitride was an excellent filler for polymer. Using functional boron nitride nanoparticles and natural latex as raw materials, boron nitride nanochips / natural rubber composites with different contents were prepared by coprecipitation in formic acid solution. The tensile and thermal conductivity of the composites were tested and analyzed by XRD,SEM,DMA,. The results showed that the mechanical strength of the composites increased significantly with the addition of boron nitride nanoparticles. A special net-like structure prepared in this experiment provides more ways for heat transfer, and can improve the thermal conductivity of the composites. When the amount of boron nitride is 5 wt%, the thermal conductivity of the composites can be improved when the amount of boron nitride is 5 wt%. The thermal conductivity of rubber was 0.192 W m-1K-1, which was significantly higher than that of pure sample (0.152 W m-1K-1). Different types of polyacrylamide, boron nitride / polyacrylamide were prepared from polyacrylamide, sodium alginate and boron nitride nanoparticles. Sodium alginate / polyacrylamide and boron nitride nanoparticles / sodium alginate / polyacrylamide) hydrogels were used to test the tensile and swelling properties of the samples. The results show that the structure of the three-network hydrogels is more compact than that of single-network polyvinyl alcohol hydrogels. The tensile strength and thermal properties of hydrogels can be significantly improved by boron nitride nanoparticles and new ionic crosslinking networks. Compared with polyacrylamide hydrogels, the maximum degradation temperature, tensile strength and modulus of the three-network hydrogels were increased by 12 鈩，
本文编号：2344478
[Abstract]:Because of its unique two-dimensional layered structure, excellent mechanical strength, thermal conductivity, electrical insulation, and chemical and thermal stability, hexagonal boron nitride has a broad application prospect in enhancing polymer properties. In this paper, the preparation of boron nitride nanoparticles and the effects of boron nitride nanoparticles on the properties of polyvinyl alcohol, natural rubber and polyacrylamide hydrogel polymer composites are studied, including the following aspects: 1. The functionalized boron nitride nanocrystals were successfully prepared by high temperature and ultrasonic treatment. The (XRD), was diffracted by (FTIR), X ray by Fourier transform infrared spectroscopy (FTIR). The structure and morphology of functionalized boron nitride nanocrystals were characterized by transmission electron microscopy (TEM) (TEM) and Raman (Laman). The results show that boron nitride nanocrystals with large size and less layers can be prepared by this method. There are a large number of hydroxyl groups on the nanocrystals, which is conducive to further functionalization. 2. A series of boron nitride / polyvinyl alcohol composites with different contents were prepared by solution blending method using functional boron nitride nanoparticles and polyvinyl alcohol as raw materials. The FTIR,XRD, scanning electron microscope (SEM),) differential scanning calorimetry (DSC),) thermogravimetric analysis (TGA) was used to analyze the tensile properties of (TGA), and the dynamic mechanical properties (DMA). The results show that the nanoparticles are uniformly dispersed in the polymer, and there is no obvious agglomeration phenomenon, and there is a hydrogen bond interaction between the nanoparticles and the polyvinyl alcohol matrix. The thermal properties of the polymer can be improved by adding a small amount of boron nitride nanoparticles. The results of static and dynamic mechanical tests showed that the tensile strength and storage modulus of boron nitride nanocrystals increased by 87.5% and 43% respectively, which indicated that boron nitride was an excellent filler for polymer. Using functional boron nitride nanoparticles and natural latex as raw materials, boron nitride nanochips / natural rubber composites with different contents were prepared by coprecipitation in formic acid solution. The tensile and thermal conductivity of the composites were tested and analyzed by XRD,SEM,DMA,. The results showed that the mechanical strength of the composites increased significantly with the addition of boron nitride nanoparticles. A special net-like structure prepared in this experiment provides more ways for heat transfer, and can improve the thermal conductivity of the composites. When the amount of boron nitride is 5 wt%, the thermal conductivity of the composites can be improved when the amount of boron nitride is 5 wt%. The thermal conductivity of rubber was 0.192 W m-1K-1, which was significantly higher than that of pure sample (0.152 W m-1K-1). Different types of polyacrylamide, boron nitride / polyacrylamide were prepared from polyacrylamide, sodium alginate and boron nitride nanoparticles. Sodium alginate / polyacrylamide and boron nitride nanoparticles / sodium alginate / polyacrylamide) hydrogels were used to test the tensile and swelling properties of the samples. The results show that the structure of the three-network hydrogels is more compact than that of single-network polyvinyl alcohol hydrogels. The tensile strength and thermal properties of hydrogels can be significantly improved by boron nitride nanoparticles and new ionic crosslinking networks. Compared with polyacrylamide hydrogels, the maximum degradation temperature, tensile strength and modulus of the three-network hydrogels were increased by 12 鈩，
本文编号：2344478
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