Synthesis and Characterization of Perovskite Oxide Reinforced Polymer Nanocomposites
Synthesis and Characterization of Perovskite Oxide Reinforced Polymer Nanocomposites
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钙钛矿氧化物增强聚合物纳米复合材料的合成与表征
DOI：
10.1093/micmic/ozad067.944
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发表时间：
2023
影响因子：
2.8
通讯作者：
Luo, Zhiping
中科院分区：
文献类型：
--
作者：
McClain, Starfari T;Murray, Thomas;Harry, Richard I;Shrivastava, Navadeep;Ede, Sivasankara Rao;Zainuddin, Shaik;Luo, Zhiping
来源于自然资源的高分子材料是一种资源丰富、前景广阔的材料，是不可降解高分子材料的环境友好型替代品。这些天然聚合物，如壳聚糖，纤维素和淀粉[1]，是各种应用的有利候选物，如锂离子电池的凝胶电解质和隔膜，染料敏化太阳能电池，超级电容器，燃料电池等。然而，与不可降解的石油基聚合物相比，这些聚合物显示出有限的机械性能[2]。因此，这些聚合物通常与不可降解的聚合物结合使用，使它们部分可降解，或通过添加纳米填料来实现有利的功能，使它们与合成聚合物相当。纳米结构的层状材料被成功地用作几种聚合物基体中的填料。2D层的插层和剥离导致聚合物的机械和摩擦学性能的改善，以及填料的一些功能。越来越多地寻求这种层状填料作为用于包装和相关应用的可生物降解的绿色聚合物的一种增强材料。纳米填料的引入也是克服某些绿色聚合物的较短保质期和不期望的结晶特性的有前景的策略。此外，纳米结构填料可以改善绿色聚合物的加工性能。然而，在聚合物基复合材料中的层状纳米填料往往被限制，以改善复合材料的物理性能。为了确定聚合物材料的独特功能，应使用具有目标功能的纳米材料作为纳米填料。已经报道了层状钙钛矿，例如Ruddlesden-Popper相、Dion-Jacobson相和Aurivillius相[3]。在这项工作中，我们合成了天然衍生的聚合物，在聚合物中用剥离的钙钛矿氧化物片增强。K2 La 2 Ti 3 O 10（KLTO）是使用改进的Pechini方法合成的[4，5]。采用固相反应法合成了K2 Gd 2 Ti 3 O 10（KGTO）。将合适化学计量比的前驱体K2 CO 3、Gd 2 O3和TiO 2置于砂浆粉中进行均匀混合。用5%Eu2O3前体代替钆前体。将这些粉末状颗粒前体粉碎成非常细的粉末，并充分混合40分钟。将细粉末产物转移到氧化铝坩埚中，并在空气炉中首先在550 ℃下加热2小时，然后在1,150 ℃下加热6小时，随后炉冷却至室温。此外，将产物粉碎成细白色粉末以合成聚偏氟乙烯（PVDF）及其共聚物聚偏氟乙烯-三氟乙烯（PVDF-TrFE）基质中的纳米复合材料。块体和剥离的K2 La 2 Ti 3 O 10（KLTO）的XRD图案分别示于图1a和图1b中。本体样品表现出高结晶度。剥离的结构如图1c所示，显示了层状结构。KGTO粉末的SEM图像示于图Id中。KLTO/PVDF-TrFE复合材料的SEM图像如图2a所示，K、La、Ti和O的元素图分别如图2b-e所示，显示出元素的均匀分布，表明分散度高[6-8]。
Polymers derived from natural resources are abundant and promising materials, as environmentally benign alternatives for nondegradable polymers. These natural polymers, such as chitosan, cellulose and starch [1], are favorable candidates for a variety of applications, such as gel electrolyte and separator membranes for Li-ion batteries, dye-sensitized solar cells, supercapacitors, fuelcells, etc. However, these polymers have shown limited mechanical properties as compared to non-degradable petroleum-based polymers [2]. Therefore, these polymers are often used in conjunction with non-degradable polymers, making them partially degradable or by adding nanofillers to achieve favorable functionality so that they are comparable to synthetic polymers. Nanostructured layered materials are successfully used as fillers in several polymer matrices. The intercalation and exfoliation of 2D layers resulted in the improved mechanical and tribological properties of the polymers, in addition to some functionality of the filler. Such layered fillers are increasingly sought as a type of reinforcement for biodegradable green polymers for packaging and related applications. The incorporation of nanofillers is also a promising strategy to overcome shorter shelf life and undesirable crystallization characteristics of some green polymers. Furthermore, nanostructured fillers can improve the processibility of green polymers. However, the layered nanofillers in the polymer-matrix composites are frequently limited to improve the physical properties of the composites. To ascertain a unique functionality to a polymeric material, nanomaterials with targeted functionality should be used as the nanofillers. Layer perovskites have been reported, such as the Ruddlesden–Popper phase, Dion–Jacobson phase, and Aurivillius phase [3]. In this work, we synthesis naturally derived polymers reinforced with exfoliated perovskite oxide sheets in the polymers.The K2La2Ti3O10 (KLTO) was synthesized using modified Pechini method [4, 5]. The K2Gd2Ti3O10 (KGTO) was synthesized by a solid-state reaction method. A proper stoichiometric ratios of the precursors K2CO3, Gd2O3 and TiO2 were placed in a mortar-pastel for homogeneous mixing. The gadolinium precursor was replaced by 5% Eu2O3 precursor. These powder granular precursors were crushed into a very fine powder and mixed very well for 40 min. The fine powder product was transferred to an alumina crucible and heated in an air furnace at first at 550 C for 2 h, then at 1,150 C for 6 h, followed with furnace cooling to room temperature. Further, the product was crushed into fine white powders to synthesize nanocomposites in the matrix of polyvinylidene fluoride (PVDF) and its copolymer, polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE). The XRD patterns of bulk and exfoliated K2La2Ti3O10 (KLTO) are shown in Fig. 1a and 1b, respectively. The bulk sample exhibits high crystallinity. The exfoliated structure is shown in Fig. 1c showing layered structures. The SEM image KGTO powder is shown in Fig. 1d. The SEM image of the KLTO/PVDF-TrFE composite is shown in Fig. 2a, and elemental maps of K, La, Ti and O are shown in Fig. 2b–e, respectively, exhibiting uniform distribution of the elements indicating a high dispersion degree [6–8].