【作者】 午海霞；

【导师】 刘昌华；

【作者基本信息】 西南大学 ， 无机化学， 2010， 硕士

【摘要】 α-磷酸锆(α-ZrP)是一类具有规整的层状结构的阳离子型化合物,由于具有高的离子交换容量、尺寸易控性、易插层易剥离性以及表面官能团的可操控和可设计性等特点,因而在聚合物改性方面有着不可估量的应用前景。本文正是在前人研究的基础上,以回流法制备α-ZrP晶体,进而用正丁胺改性以获得更大的层间距以利于聚合物分子链扩散插层,制备了豌豆淀粉／α-磷酸锆(PS／ZrP)和壳聚糖／α-磷酸锆(CS／ZrP)纳米复合材料,研究α-ZrP对纳米复合材料结构和性能的影响,重点研究了α-ZrP纳米粒子和聚合物基体间的界面作用强度及其对复合材料结构和性能的影响。利用a-ZrP的表面官能团可操控性,在其表面引入有机官能团(-COOH),成功合成有机膦酸锆(甘氨酸-N,N-双亚甲基膦酸锆,ZGDMP),进而制得豌豆淀粉／有机膦酸锆(PS/BA-ZGDMP)和壳聚糖／有机膦酸锆(CS/BA-ZGDMP)纳米复合材料,通过对比的方法研究引入的有机官能团对纳米粒子和聚合物基体间界面作用强度的影响和对复合材料的结构和性能的影响。具体研究工作如下：1、用流延法制备了甘油增塑的豌豆淀粉／α-磷酸锆(PS／ZrP)纳米复合材料,使用傅里叶红外(FT-IR)、X-射线衍射(XRD)、扫描电镜(SEM)、热重分析(TGA)等方法研究α-ZrP对复合材料结构和性能的研究。结果表明,PS和ZrP之间形成强的氢键作用,提高了PS和ZrP之间的界面粘结性和相容性。2、用回流法成功合成具有较大层间距和极性官能团(-COOH)的有机膦酸锆(甘氨酸-N,N--双亚甲基膦酸锆,ZGDMP),进而用正丁胺修饰,使其层间距扩大到1.76nm。用流延法制备了甘油增塑的豌豆淀粉／有机膦酸锆(PS/BA-ZGDMP)纳米复合材料。与PS/ZrP体系相比,PS/BA-ZGDMP体系表现出两个重要的特点：(ⅰ)复合材料的拉伸强度最大可以增大到12.14MPa,明显高于PS／ZrP体系的9.44MPa；(ⅱ)吸湿性能降低到59.1%,低于PS／ZrP体系的63.1%。这些性能的改善可归因于引入的极性有机官能团,其与极性淀粉分子间形成范德华力和更强的氢键作用,增强了PS和BA-ZGDMP间的界面粘结性和界面作用进而改善复合材料的性能。3、用流延法制备了壳聚糖／α-磷酸锆(CS／ZrP)纳米复合材料,其中壳聚糖作为基体,α-ZrP作为纳米填料,研究a-ZrP对复合材料结构和性能的影响。傅里叶红外变换光谱(FT-IR)测试表明CS和a-ZrP之间形成强的相互作用。X-射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)的结果表明,α-ZrP均匀分散到壳聚糖基体中,并形成了中等剥离程度的结构。Pukanszky模型中用界面作用参数B值来衡量壳聚糖基体和α-ZrP填料之间的界面作用大小,结果表明,当a-ZrP含量为2 wt%时,复合材料最有最大B值(3.2)表明具有最强的界面作用。4、成功制备具有极性官能团(-COOH)的有机膦酸锆(甘氨酸-N,N-双亚甲基膦酸锆,ZGDMP),并用傅里叶红外变换光谱(FT-IR)、X-射线衍射(XRD)和扫描电镜(SEM)对其进行表征。使用正丁胺修饰(BA-ZGDMP),其层间距扩大到1.76nm。用流延法制备了壳聚糖／有机膦酸锆(CS/BA-ZGDMP)纳米复合材料。红外光谱表明,CS和BA-ZGDMP间形成强的相互作用。与纯壳聚糖相比,当BA-ZGDMP的添加量为1.0wt%时,复合材料的拉伸强度和断裂伸长率分别提高了35.1%和15.6%。并且,BA-ZGDMP的加入也提高了复合材料的耐水性能。更多还原

【Abstract】 a-Zirconium phosphate (a-ZrP) is a kind of cationic compounds. In addition to the layered structure, a-ZrP has a number of additional advantages, including a much higher ion exchange capacity, ease of dimensional control, ease of intercalation/exfoliation, and controllable/designable surface functionality. Thus, a-ZrP has a prospect of incalculable in the improvement of polymer. properties. Based on the previous studies, a-ZrP has been synthesized using the refluxed method and further modified by the n-butylamine to obtain the enlarger interlayer space. Then pea starch/a-zirconium phosphate (PS/ZrP) and chitosan/a-zirconium phosphate (CS/ZrP) nanocomposites have been prepared. The thesis focuses on the interfacial interaction between polymer matrix and nano-particles. The structure and properties of nanocomposites have also been discussed. And then a new type of layer zirconium phosphonate (zirconium glycine-N, N-dimethylphosphonate, abbreviated as ZGDMP), with the functional group-COOH has been synthesized. And pea starch/zirconium phosphonate (PS/BA-ZGDMP) and chitosan/zirconium phosphonate (CS/BA-ZGDMP) nanocomposites have been prepared. The interfacial interaction on the structure and properties has been discussed through the comparision.The main contents and results in this thesis are as follows:1. Glycerol-plasticized pea starch/a-zirconium phosphate (PS/ZrP) nanocomposite films with different loading levels of a-zirconium phosphate (a-ZrP) were prepared by a casting and solvent evaporation method. The effects of the a-zirconium phosphate on the structure and properties of the PS/ZrP films were characterized by Fourier transform infrared (FT-IR) spectroscopy, wide-angle X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and tensile testing. The results indicated that hydrogen bonds formed between pea starches (PS) and a-ZrP, which improved interface adhesion and the compatibility between PS and a-ZrP.2. A new type of layered zirconium glycine-N, N-dimethylphosphonate (abbreviated as ZGDMP), with enlarged interlayer d-spacing and the functional group-COOH, was prepared. ZGDMP was successfully intercalated by n-butylamine which further increased the d-spacing to 1.76 nm. The modified ZGDMP (hereafter BA-ZGDMP) was used as nanofiller in a glycerol-plasticized thermoplastic pea starch (PS) matrix. Compared with previous studies on a-ZrP-reinforced pea starch matrix, the present system of BA-ZGDMP reinforced pea starch (PS/BA-ZGDMP) presents two significant points:(i) the tensile strength was enhanced to 12.14 MPa, which was remarkably higher than that of the PS/ZrP system (9.44 MPa); and (ii) the moisture uptake in PS/BA-ZGDMP was reduced to 59.1%, which was lower than that of the PS/ZrP system (63.1%). These results can be attributed to the introduction of the polar carboxylate ions (-COO), which resulted in Van der Waals force as well as stronger hydrogen bonding, and stronger interfacial adhesion and interaction between the polar BA-ZGDMP and the polar starch matrix.3. The objective of this work is to prepare nanocomposite films of chitosan/a-zirconium phosphate (CS/ZrP) by casting process, using a-zirconium phosphate (a-ZrP) as nanofillers and chitosan as matrix. The effects of a-zirconium phosphate on the structure and properties of the nanocomposites were investigated. FT-IR revealed that a strong interaction between a-ZrP and chitosan formed during the film-forming process. The results from scanning electron microscope (SEM) and transmission electron microscope (TEM) indicated that a-ZrP uniformly dispersed and formed moderate exfoliated a-ZrP nanoplateletes in chitosan matrix. The parameter B calculated from tensile yield stress according to Pukanszky model was used to value the interfacial interaction between chitosan matrix and a-ZrP. The film with loading of 2 wt%α-ZrP had the highest B value (3.2), indicating the strongest interfacial interaction. 4. A new type of layer zirconium phosphonate (zirconium glycine-N, N-dimethylphosphonate, abbreviated as ZGDMP), with the functional group-COOH, has been successfully prepared and characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). In order to confirm the effect of the functional group-COOH on the structure and properties of composites, then a series of chitosan/zirconium phosphonate modified by n-butylamine (BA-ZGDMP) nanocomposite films were prepared by casting process. FTIR spectra suggested that strong interactions existed between BA-ZGDMP and chitosan matrix. Compared with neat CS film, the tensile strength (σb) and the elongation at break (εb) of the nanocomposite film were greatly improved by 35.1% and 15.6%, respectively, only with 1.0 wt% BA-ZGDMP loading. In addition, the BA-ZGDMP also improved the water resistance of the nanocomposites.更多还原