HIPS/纳米CaCO3复合材料性能与结构研究

通过混合、熔融挤出,将纳米CaCO3填充到高抗冲聚苯乙烯(HIPS)中,制得高强度、低成本的HIPS/纳米CaCO3复合材料。对该复合材料进行了力学性能测试和微观结构观察,并讨论了纳米CaCO3增韧HIPS的机理。结果表明,纳米CaCO3用量为12份时,对HIPS/纳米CaCO3复合材料有明显的增韧增强作用,而且可使原料成本降低12%左右。     

PP/EPR/纳米CaCO3三元共混体系的研究

采用双辊混炼和挤出制样的方法制备了PP／EPR／纳米CaCO3复合材料。采用扫描电镜(SEM)、透射电镜(TEM)对复合材料进行了断面观察，并测试了复合材料的力学性能。结果表明，对纳米CaCO3进行表面改性和用适当的共混方法，可以显著提高复合材料的冲击强度。对复合材料冲击断面进行SEM观察时发现，材料发生了韧性断裂。     

纳米CaCO3/PVC复合材料结构形态与冲击性能

对改性纳米CaCO3/PVC复合材料进行冲击强度的测试。结果表明，改性纳米CaCO3可提高PVC复合材料的裂缝引发能和裂缝增长能，其中裂缝增长能的提高尤为明显。复合材料的单缺口冲击强度达到81.1kJ.m^-2。用透射电子显微镜及扫描电子显微镜观察了纲米纳米CaCO3/PVC复合材料的微观结构及断面形态，发现表面改性后纳米CaCO3在PVC基体中达到了纳米级的分散，复合材料的断面产生了大量的网丝状结构。复合材料的微观结构进一步证实了纳米纳米CaCO3对PVC基体的显著增韧作用。     

原位聚合法制备纳米CaCO3/PVAc复合材料

将纳米CaCO3先分散在醋酸乙烯(VAc)中,再进行VAc溶液聚合,以原位聚合的方法制得纳米CaCO3/PVAc复合材料.主要研究了纳米CaCO3在VAc中的最佳分散条件和VAc溶液聚合的最佳条件参数,对不同纳米CaCO3含量的复合材料进行红外、透射电镜表征和断裂强度、断裂伸长率等性能的测试.结果显示:CaCO3与PVAc存在化学键的结合,CaCO3在PVAc中呈纳米级分散,当纳米CaCO3质量分数为0.2%～0.3%时,该复合材料力学性能最佳.     

P(St/MAH/BA)改性纳米CaCO3对PS的增韧研究

采用由苯乙烯(St)、马来酸酐(MAH)和丙烯酸丁酯(BA)组成的三元聚合物P(St/MAH/BA)作为纳米CaCO3-的表面改性剂,制备了纳米CaCO3/PS复合材料,并对复合材料的力学性能进行了测试.结果表明,P(St/MAH/BA)作为纳米CaCO3表面改性剂与PS的相容剂能够明显改善纳米CaCO3/PS复合材料的力学性能,经P(St/MAH/BA)改性的纳米CaCO3对PS具有明显的增韧改性作用.     

聚乳酸/酯化纤维素/纳米CaCO_3复合材料的制备与表征

采用熔融共混法制备了聚乳酸(PLA)/酯化纤维素/纳米CaCO3复合材料,并通过力学性能测试、差示扫描量热仪、热重分析和扫描电镜等测试手段对复合材料的性能进行了表征。结果表明,当酯化纤维素和纳米CaCO3的总含量小于5%时,能够起到较好的增强作用,复合材料的力学性能明显优于纯PLA;酯化纤维素和纳米CaCO3的加入起到了异相成核作用,但会降低复合材料的热稳定性;酯化纤维素在复合材料中分散充分,无聚集现象;但当填料总含量大于10%时,纳米CaCO3发生明显发生聚集。     

聚乳酸/酯化纤维素/纳米CaCO3复合材料的制备与表征

采用熔融共混法制备了聚乳酸(PLA)/酯化纤维索/纳米CaCO3复合材料,并通过力学性能测试、差示扫描量热仪、热重分析和扫描电镜等测试手段对复合材料的性能进行了表征.结果表明,当酯化纤维素和纳米CaCO3的总含量小于5%时,能够起到较好的增强作用,复合材料的力学性能明显优于纯PLA;酯化纤维素和纳米CaCO3的加入起到...     

纳米CaCO_3表面改性及其对PVC复合材料性能的影响

分别采用十八胺、十二胺和正辛胺对纳米CaCO3进行湿法改性,制备了聚氯乙烯(PVC)/纳米CaCO3复合材料,系统研究了不同改性剂改性的纳米CaCO3对PVC基复合材料力学性能的影响。结果表明:3种改性剂均可以与纳米CaCO3表面结合,形成一有机层,阻止了纳米CaCO3团聚,使改性后的粒子可以均匀分散在PVC基体中;十八胺、十二胺和正辛胺改性后的纳米CaCO3均可显著提高PVC复合材料的缺口冲击强度,并且随着改性剂分子链长度的增加,冲击强度也略有提高;改性纳米CaCO3可以略微提高复合材料的弯曲强度,但材料的拉伸强度略有下降。     

不同形态纳米级CaCO3改性PP研究

研究了不同形态纳米级CaCO3改性PP复合材料的力学性能及其对PP球晶形态的影响。结果表明，纳米级CaCO3形态不同，复合材料力学性能不一样，立方形纳米级CaCO3有利于改善复合材料的冲击性能，而纤维状纳米级CaCO3则能明显改善材料的拉伸性能。纳米级CaCO3能使PP球晶明显的细化．并能促进β晶型的生成。     

纳米CaCO3及偶联剂对小本体PP结晶的影响

采用熔融共混法制备了小本体聚丙烯/纳米CaCO3复合材料(SBPP/纳米CaCO3),研究了经铝钛复合偶联剂处理前后的纳米CaCO3粒子对SBPP结晶性能的影响.结果表明纳米粒子能够诱导β晶的形成,提高SBPP的结晶度,降低SBPP球晶尺寸,使得球晶均匀程度增加,并且纳米CaCO3经偶联剂处理后以上几种效果更为显著;纳米CaCO3可以提高材料的结晶温度和结晶速率,但经偶联剂处理的纳米粒子的结晶速率却小于未经偶联剂处理的材料的结晶速率,说明偶联剂的加入在一定程度上抑制了纳米CaCO3对SBPP/纳米CaCO3复合材料的结晶过程.     

CaCO_3纳米粉填充环氧树脂分散技术研究

对CaCO3 纳米粉填充环氧树脂的均匀分散技术进行了探讨。采用超声波振动和对CaCO3纳米粉进行硅烷偶联处理两种方法改进CaCO3 在环氧树脂中的分散效果。扫描电镜观察表明 ,以上两种方法比普通搅拌混合效果显著 ,实现了CaCO3 纳米粉在环氧树脂中的均匀分散。     

纳米CaCO3填充环氧树脂分散技术研究

对纳米CaCO3填充环氧树脂的均匀分散技术进行了探讨。采用超声波振动和对纳米CaCO3进行硅烷偶联处理两种方法改进CaCO3在环氧树脂中的分散效果。扫描电镜观察表明，以上两种方法比普通搅拌混合效果更好，实现了纳米CaCO3在环氧树脂中的均匀分散。     

功能化纳米碳酸钙母料的制备与表征

采用溶液聚合法分别制备了表面包覆有载体树脂、复合弹性体和环氧基团的P型和H型功能化纳米碳酸钙母料,并对两种母料的产率、化学结构和热性能进行了研究.结果表明:纳米CaCO3表面的复合包覆层含有弹性体、载体树脂和将来可与PET端基发生反应的环氧基团.由于载体树脂种类的差异,导致两种母料的热分解起始温度Tdo不同,其中,H型母料的热稳定性略高于P型母料,但是,不同的载体树脂对母料的产率没有明显影响.     

CaCO3纳米粉填充环氧树脂分散技术研究

本文对CaCO3纳米填充环氧树脂的均匀分散技术进行了探讨。采用超声波振动和对CaCO3纳米粉进行硅烷偶联处理两种方法改进CaCO3在环氧树脂中的分散效果。扫描电镜观察表明，以上两种方法比普通搅拌混合效果显著，实现了CaCO3纳米粉在环氧树脂中的均匀分散。     

Comparative Study on Improvement in Mechanical and Flame Retarding Properties of Epoxy-CaCO3 Nano and Commercial Composites

ABSTRACT

Commercial and nano calcium carbonate (CaCO₃) filled epoxy composites were processed at 2 to 10 wt% compositions. Nano size CaCO₃ was synthesized using in-situ deposition technique. Its nanosize and mixing with epoxy were confirmed by X-ray diffraction (XRD) method. X-ray diffractograms show that complete exfoliation occurs in the case of nanosize particles while micron size particles do not exfoliate. The effect of nanosize and commercial CaCO₃ was studied on mechanical and flame retarding properties. The impact strength of composite increased up to 6 wt% loading of nano filler and further decreased. Young's modulus was observed at 1400 Mpa and 1100 Mpa for nano and commercial CaCO₃, respectively at their 10 wt% loading, while pure epoxy showed 1000 Mpa; likewise, flame retarding properties improved six to four times on loading of nano and commercial CaCO₃, respectively in comparison to pure epoxy resin. The improvement is due to exfoliation of nano in epoxy matrix, which is observed by X-ray diffractograms.     

Improvements of the structural,thermal, and mechanical properties of structural adhesive with functionalized boron nitride nanoparticles

Investigations on the production and development of nanoparticle-reinforced polymer materials have been attracted attention by researchers. Various nanoparticles have been used to improve the mechanical, chemical, thermal, and physical properties of polymer matrix composites. Boron compounds come to the fore to improve the mechanical and thermal properties of polymers. In this study, mechanical, thermal, and structural properties of structural adhesive have been examined by adding nano hexagonal boron nitride (h-BN) to epoxy matrix at different percentages (0.5, 1, 2, 3, 4, and 5%). For this purpose, nano h-BN particles were functionalized with 3-aminopropyltriethoxysilane (APTES) to disperse the h-BN nanoparticles homogeneously in epoxy matrix and to form a strong bond at the matrix interface. Two-component structural epoxy adhesive was modified by using functionalized h-BN nanoparticles. The structural and thermal properties of the modified adhesives were investigated by scanning electron microscopy and energy dispersion X-ray spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis techniques. Tensile test and dynamic mechanical analysis were performed to determine the mechanical properties of the adhesives. When the results obtained from analysis were examined, it was seen that the nano h-BN particles functionalized with APTES were homogeneously dispersed in the epoxy matrix and formed a strong bond. In addition that, it was concluded from the experimental results that the thermal and mechanical properties of adhesives were improved by adding functionalized nano h-BN particles into epoxy at different ratios.     

纳米Al2O3/环氧树脂复合材料的制备及性能

在原位法制备纳米复合材料时，要使纳米粒子在树脂中分散均匀，必须首先获得稳定的单体悬浮体系。基于这一原理，本文通过对纳米Al2O3表面改性即选择合适的分散剂，获得稳定的纳米Al2O3/丙酮悬浮液，然后将环氧树脂溶解于其中，制得纳米Al2O3／环氧树脂复合材料。运用透射电子显微镜，观察了纳米Al2O3在环氧基体中的分散情况。分析并讨论了纳米Al2O3含量对该复合材料力学性能的影响。结果表明：利用稳定的悬浮体系能制得分散较为均匀的纳米复合材料，在纳米Al2O3含量为5％的情况下，纳米复合材料的力学性能达到最优。     

Temperature effects on rigid nano‐silica and soft nano‐rubber toughening in epoxy under impact loading

The rigid nano‐silica and soft nano‐rubber toughening effects on neat epoxy under impact loading in a range of ?50 to 80 °C were investigated. Nanosilica particles (20 nm) toughened neat epoxy at all temperatures with a maximum toughening efficiency at ?50 °C and lower efficiency at elevated temperatures. In contrast, except at ?50 °C, nano‐rubber particles (100 nm) showed the deterioration effect on the impact fracture toughness of epoxy resin. Scanning electron microscopy examinations revealed that the crack pinning and local epoxy deformation induced by rigid particles in term of nano‐silica/epoxy and nano‐rubber/epoxy interfacial debonding (at ?50 °C) led to positive toughening efficiency on neat epoxy. However, at 20 and 80 °C, the rubber cavitations/void plastic growth was significantly suppressed under the impact loading, which led to the negative toughening efficiency on epoxy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45319.     

纳米CaCO_3/PVC共混体系的研究

研究了纳米级CaCO3 粒子的微观形态 ,以及纳米CaCO3/PVC共混体系的流变性能和力学性能。结果表明 ,纳米CaCO3 加入量为 9质量份时 ,纳米CaCO3/PVC共混体系的缺口冲击强度可达到 31 4kJ/m2 。纳米Ca CO3 对PVC共混体系具有显著的增韧效果     

亚微米CaCO_3填充UPVC的性能与影响因素研究

研究了硬脂酸包覆的微米—亚微米CaCO3 填充的力学性能与影响因素的关系。研究结果表明,增加CaCO3 用量、减小CaCO3 粒径均有利于材料模量的提高;减小CaCO3 用量或粒径有利于保持UPVC的较高屈服强度。适量的亚微米级CaCO3 可明显提高UPVC的韧性,为了获得高的抗冲击强度宜用分子量较高的树脂,并在较高的温度下塑炼加工。