改性氧化石墨/聚合物的制备及其体外抗凝血性能的评价

利用溶液插层法合成了新型的硅橡胶/氧化石墨-十八烷基二甲基-2-羟乙基溴化铵-肝素纳米抗凝血复合膜材料,并通过机械性能测试、X射线衍射、血小板黏附试验和肝素扩散速率测定实验对复合膜材料的力学性能和血液相容性进行了表征.结果表明,这种新型的抗凝血生物材料具有良好的力学性能和优良的血液相容性,并且肝素扩散缓慢,具有相对长效的抗凝血活性,可望在生物医学工程方面得到广泛的应用.     

蒙脱土/聚合物纳米复合抗凝血膜的制备及其性能研究

利用溶液插层法合成了新型的蒙脱土-十八烷基二甲基-2-羟乙基溴化铵-肝素/硅橡胶抗凝血复合膜材料,并通过红外光谱、X射线衍射和机械性能测试对复合膜进行了表征.将纳米复合膜用于体外实验,通过观察溶血率、复钙化时间和血小板黏附实验来对其血液相容性进行了表征.研究结果表明蒙脱土/聚合物纳米复合膜具有较好的抗凝血性能.     

氧化石墨插层纳米复合材料的制备研究进展

氧化石墨（GO）插层纳米复合材料是一种新型的纳米复合材料。介绍了氧化石墨的结构、制备方法和性质；重点论述了聚合物/氧化石墨插层纳米复合材料和无机物/氧化石墨插层纳米复合材料的制备研究进展，介绍了半导体氧化物/氧化石墨插层纳米复合材料。     

GO负载纳米Al2O3对环氧树脂耐磨性能的影响

为了研究出一种耐磨性能优异的环氧树脂基纳米复合材料,将球形纳米氧化铝经γ-氨丙基三甲氧基硅烷改性后负载到氧化石墨烯表面,再将其作为填料加入到环氧树脂中,制备出球形纳米氧化铝/氧化石墨烯/环氧树脂新型纳米复合材料.利用硬度计、磨耗仪及万能试验机,分别对纳米复合材料的硬度、磨损量、弯曲性能和冲击性能进行测试.试验结果表明:该新型纳米复合材料相较于纯环氧树脂,磨损量减少了 52.5％;弯曲强度达到了 121.4 MPa,为纯环氧树脂的1.44倍;冲击强度达到了 27.4 J/m2,为纯环氧树脂的5.96倍.球形纳米氧化铝大的比表面积与表面作用力增强了片层状氧化石墨烯和环氧树脂的表面作用,进而使该新型纳米复合材料表现出了优异的耐磨性能.     

双导电相硅橡胶力敏材料的制备与电性能分析

为了获得具有较好压阻稳定性和重复性的力敏复合材料,在炭黑/硅橡胶复合体系中加入纳米氧化钌,完善补充导电相的同时加固硅橡胶交联网络。采用溶剂热还原法制备金属钌纳米颗粒,在空气中热氧化,得到尺寸为数十纳米的氧化钌颗粒;采用溶剂共混的方法制备炭黑/硅橡胶共混胶,用研磨分散的方法将纳米二氧化钌加入炭黑/硅橡胶共混胶中,硫化成型后得到氧化钌(RuO2)-炭黑(CB)/硅橡胶(MVQ)双导电相复合材料。采用自建的压阻性能测试系统测试了复合材料的压阻性能,测量结果表明,CB/MVQ体系中加入一定用量的RuO2其压阻重复性变好,压阻蠕变性得到改善;用扫描电镜、透射电子显微镜分析了复合材料的微观结构,并用能谱分析结合电子衍射图证明了纳米氧化钌以纳米结构存在于复合材料中,丰富和完善了炭黑导电网络,加固了硅橡胶交联网络,这些因素是导致压阻重复性提高的主要因素。     

卵磷脂-肝素/蒙脱土纳米中间体的制备及血液相容性的研究

把具有良好抗凝血性能的卵磷脂-肝素(Pc-hep)复合物插层进入蒙脱土(MMT)中,制备出一系列新型的PC-hep/MMT纳米中间体.通过XRD对纳米中间体的结构和性能进行了表征;在此基础上,用复钙化时间曲线和溶血试验表征了纳米中间体的血液相容性,可以看出当随着材料的浓度增加,复钙时间曲线由陡峭趋于平滑;同时材料的溶血率都低于5%说明材料有很好的血液相容性,因此可以作为生物材料用于医用领域.     

添加剂对聚吡咯/氧化石墨纳米复合材料结构和性能的影响

采用单体原位聚合法制备了三种聚吡咯/氧化石墨纳米复合材料。通过XRD、FT-IR和TEM对产物进行结构表征,探讨了未加添加剂及分别以N aOH和十二烷基苯磺酸钠为添加剂制得的聚吡咯/氧化石墨纳米复合材料的结构与性能的差别。结果表明,未加添加剂和以N aOH为添加剂时产物为非晶态的剥离型聚吡咯/氧化石墨纳米复合材料;而以十二烷基苯磺酸钠为添加剂时可得到具有层状有序结构的插层型聚吡咯/氧化石墨纳米复合材料。插层型聚吡咯/氧化石墨纳米复合材料的导电和电化学性能优于剥离型聚吡咯/氧化石墨纳米复合材料,它们的提高归因于聚吡咯分子链共轭程度的增加。     

羟基磷灰石对硅橡胶复合材料抗凝血性能的影响

本研究制备了在165℃×10min条件下交联的机械共混羟基磷灰石和硅橡胶生物材料,并通过动态凝血试验、溶血率测定、血小板粘附的SEM观察等方法评价了羟基磷灰石与硅橡胶复合材料的血液相容性.结果表明,含60%羟基磷灰石的复合材料血液相容性最佳.     

还原温度对纳米Fe/石墨复合材料结构及微波吸收性能的影响

利用氧化石墨层间可吸附大量离子的特性使金属Fe3 吸附到氧化石墨层间,再通过H2还原制备了不同还原温度下的纳米Fe/石墨复合材料.采用元素分析、TEM、XRD、磁滞回线及电磁参数测定等手段系统考察了还原温度对纳米Fe/石墨复合材料的分子组成、晶体结构、磁学性能及微波吸收性能的影响.结果表明:纳米Fe/石墨复合材料的密度约2.4g/cm3;纳米Fe/石墨复合材料属于典型的软磁性材料;FeGO300、FeGO600和FeGO900的最大反射损耗量分别为-6.2dB、-8.9dB和-3.2dB.当厚度为1mm时,FeGO600的反射损耗大于-6dB的频段范围为11~18GHz,而FeGO600和FeGO900的最大反射损耗仍低于-6dB,因此FeGO600的微波吸波效果最好,600℃为制备纳米Fe/石墨复合吸波材料的最佳还原温度.     

双层结构纳米羟基磷灰石/硅橡胶复合材料的制备及性能

纳米羟基磷灰石/硅橡胶与硅橡胶在同时硫化的条件下制备出了双层结构的纳米羟基磷灰石/硅橡胶复合材料,利用XRD、SEM、MTT和力学性能测试等手段对复合材料进行表征.结果表明,两层材料的界面结合紧密,材料的细胞相容性好,力学性能与硅橡胶的力学性能相近,能够达到医用植入硅橡胶材料的要求.     

Biocompatible composites of fibrous nanohydroxyapatite embedded in a polydimethylsiloxane

Silicone elastomers have the potential to be a valuable biomaterial due to their mechanical and chemical properties, easy processing, and high gas permeability. Some inherent properties of the pure silicone implant such as high hydrophobicity and low load bearing capacity can be problematic for biomedical applications. The issues were addressed by fabricating hydroxyapatite nanofiber/polydimethylsiloxane nanocomposites. The morphology of nanocomposite structures was visualized by high resolution transmission electron microscopy and field emission scanning electron microscopy. Improved mechanical strength and compliance of the prepared nanocomposite structures were obtained by frequency sweep and creep measurements. Surface hydrophilicity of polydimethylsiloxane was enhanced by hydroxyapatite nanofiber incorporation into the polymer matrix. The cytotoxicity and biocompatibility of the structures were analyzed using breast epithelial cells (MDA MB 231 cell line). These studies showed that the nanocomposite scaffold did not leach any cytotoxic material and showed better cell adhesion and cell proliferation compared to the unfilled elastomer.     

Effect of multi-wall carbon nanotubes on the mechanical properties of natural rubber

Multi-walled carbon nanotubes (MWNTs) were used to prepare natural rubber (NR) nanocomposites. Our first effort to achieve nanostructures in MWNTs/NR nanocomposites were formed by incorporating carbonnanotubes in a polymer solution and subsequently evaporating the solvent. Using this technique, nanotubess can be dispersed homogeneously in the NR matrix in an attempt to increase the mechanical properties of these nanocomposites. The properties of the nanocomposites such as tensile strength, tensile modulus, tear strength, elongation at break and hardness were studied. Mechanical test results show an increase in the initial modulus for up to 12 times in relation to pure NR. In addition to mechanical testing, the dispersion state of the MWNTs into NR was studied by transmission electron microscopy (TEM) in order to understand the morphology of the resulting system. According to the present study, application of the physical and mechanical properties of carbon nanotubes to NR can result in rubber products which have improved mechanical, physical and chemical properties, compared with existing rubber products reinforced with carbon black or silicone.     

Roles of Ni/CNTs hybridization on rheological and mechanical properties of CNTs/epoxy nanocomposites

In this work, a nanoscaled Ni surface coating for multi-walled carbon nanotube (MWCNT) is proposed for the improvement of the interfacial properties between MWCNTs and epoxy resins in nanocomposites. The rheological behaviors and mechanical properties of the nanocomposites were investigated in a frequency sweep experiment with oscillatory rheometry and a universal test machine, respectively. The rheological behaviors of the nanocomposites proved the good dispersion behaviors of the Ni-coated MWCNTs in the matrix, demonstrating an increase in the suspension viscosity, G″, and G′, proving the high mechanical interfacial properties of the final composites.     

聚偏氟乙烯/碳纳米管纳米复合材料的制备和表征

采用超声波分散法制备了聚偏氟乙烯(PVDF)/多壁碳纳米管(MWCNT)复合材料。利用扫描电子显微镜、差示扫描量热法和傅立叶变换红外光谱等方法研究了复合材料的形态,考察了MWCNT用量对复合材料结晶行为和力学性能的影响。结果表明,通过超声处理,PVDF和MWCNTs之间产生了相互作用,复合体以球状的形式存在。MWCNTs的引入导致具有压电性的β相形成和屈服强度的提高。根据实验结果,对PVDF/MWCNT复合球体和β相的形成机理提出了可能的解释。     

熔体插层制备EVA/粘土纳米复合材料

通过熔体插层制备了乙烯-乙酸乙烯酯共聚物(EVA)／粘土纳米复合材料。采用FT-IR、XRD、TG分析和力学性能测试研究了有机改性粘土和EVA/粘土复合材料的结构与性能。实验结果表明，通过离子交换反应，可使长链十八胺阳离子嵌入粘土片层间，增大了粘土的片层间距；对于EVA／有机化粘土体系，通过熔体插层可使EVA分子链插层于粘土片层中，使粘土片层被进一步撑开；EVA／粘土纳米复合材料具有较好的力学性能。     

Static and dynamic mechanical properties of polydimethylsiloxane/carbon nanotube nanocomposites

The purpose of this study is to investigate the static and dynamic mechanical properties of polydimethylsiloxane (PDMS) and the mixture of PDMS and carbon nanotubes. The PDMS/CNT nanocomposites were stirred by an ultrasonic instrument to prevent agglomerations. The tested specimens of nanocomposites were manufactured by using the thermoforming method at 150 °C for 15 min. A micro tensile tester was adopted in this testing system with a maximum load of 500 mN and a crosshead extension of 150 mm. The static elastic modulus can be calculated by means of a tensile test and the average elastic modulus of pure PDMS is 1.65 MPa. In addition, the Nano Bionix tensile tester was also used to perform the dynamic mechanical analysis. Its dynamic frequency range is from 0.1 Hz to 2.5 KHz. The dynamic properties of PDMS/CNT nanocomposites such as storage and loss modulus can be obtained by this system. The storage modulus increased with the CNT content and also with the higher frequencies. Finally, the nanoindentation measurement system was employed to characterize the mechanical properties of PDMS and PDMS/CNTs. The measurement results of elastic modulus by a nanoindentation test have the similar trend with the results obtained by the tensile test method.     

Effect of Multi-Wall Carbon Nanotubes on the Mechanical Properties of Natural Rubber

Multi-walled carbon nanotubes (MWNTs) were used to prepare natural rubber (NR) nanocomposites. Our first efforts to achieve nanostructures in MWNTs/NR nanocomposites were formed by incorporating carbon nanotubes in a polymer solution and subsequently evaporating the solvent. Using this technique, nanotubes can be dispersed homogeneously in the NR matrix in an attempt to increase the mechanical properties of these nanocomposites. The properties of the nanocomposites such as tensile strength, tensile modulus, elongation at break and hardness were studied. Mechanical test results show an increase in the initial modulus for up to 12 times in relation to pure NR. In addition to mechanical testing, the dispersion state of the MWNTs into NR studied by Transmission Electron Microscopy (TEM) in order to understand the morphology of the resulting system     

纳米复合材料力学性能的研究

本文从薄膜和块体材料两个方面介绍了近年来有关纳米复合材料力学性能的研究成果。综述了薄膜和块体纳米复合材料优异的力学性能及其产生机制 ,并指出了进一步研究方向     

BMI树脂/氧化石墨纳米复合材料的制备及表征

本文以烯丙基缩合多核芳香烃(GOPNA)树脂与双马来酰亚胺(BMI)共聚制备BMI树脂,通过溶液插层的方法制备BMI树脂/氧化石墨纳米复合材料.采用X射线衍射(XRD)、透射电镜(TEM)、热重分析(TGA)研究了复合材料的结构和性能,采用电子万能试验机研宛了复合材料的力学性能.研究表明,该复合材料为刺离型纳米复合材料...