功能化氧化石墨烯/壳聚糖纳米复合材料的制备及力学性能研究

以壳聚糖为基体、氧化石墨烯为活性增强相,采用溶液复合的方法制备了氧化石墨烯/壳聚糖纳米复合材料。为使氧化石墨烯均匀地分散在壳聚糖溶液中,对氧化石墨烯的表面进行了功能化处理。通过TEM、SEM、XRD、TGA和力学实验对氧化石墨烯的分散性,复合材料的结晶性能、热性能和力学性能进行了分析。研究结果表明,表面处理后的氧化石墨烯均匀分散于壳聚糖溶液中,未出现絮凝和团聚现象,复合材料中氧化石墨烯也以层片堆叠的方式存在。复合材料中壳聚糖基体的结晶峰位置和结晶度不随氧化石墨烯的加入而改变。复合材料的杨氏模量随着氧化石墨烯含量的增加而提高,断裂伸长率随氧化石墨烯含量增加而降低;当氧化石墨烯含量达到5%(质量分数)后,材料由韧性变为脆性,强度降低。复合材料的热稳定性随着氧化石墨烯含量的增加而提高。     

碳化氧化石墨烯/壳聚糖超级电容器电极复合材料的制备及表征

采用Ar氛烧结碳化法在600℃、700℃、800℃及900℃下制备了基于氧化石墨烯（GO）/壳聚糖复合材料的超级电容器电极材料。通过XRD、SEM、FTIR及循环伏安等电化学手段,系统评价了碳化的GO/壳聚糖复合材料作为超级电容器电极材料的可能性。通过与文献报道的纯壳聚糖碳化材料的相关性能进行比较,结果表明：碳化GO/壳聚糖复合材料力学性能较纯壳聚糖碳化材料提高约67%,而且具有良好的电容器材料的性质。800℃碳化GO/壳聚糖复合材料样品的比电容达131 F/g,1 500次充放电后比电容保持率达97%。     

石墨烯/壳聚糖电化学生物传感器研究进展

石墨烯/壳聚糖是一种无机碳纳米材料和生物多糖结合在一起的新型复合材料,既有石墨烯的导电性好、化学性能稳定等特点,又兼具壳聚糖的生物官能性。主要介绍了基于石墨烯/壳聚糖材料构建的电化学生物传感器近年来在环境污染物、医学检验、食品的检测中的应用。     

氧化石墨烯/聚合物复合材料的研究进展

介绍了氧化石墨烯及其改性,氧化石墨烯/聚合物的制备方法。优异的性能使复合材料应用广泛,主要用在超级电容器、燃料电池、阻燃材料、生物医学等领域。同时提出了复合材料研究中的一些问题,如氧化石墨烯的改性及复合材料的实际应用。     

不同水醇比条件下原位聚合的聚吡咯/石墨烯复合材料的电容性能

在不同水醇比的溶剂环境下,利用原位聚合法制得聚吡咯/氧化石墨烯复合物,再经还原得到聚吡咯/还原氧化石墨烯复合材料。通过红外光谱、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等测试方法对复合材料的结构和形貌进行表征,利用电化学工作站对复合物的电化学性能进行了测试。结果表明,在不同水醇比的溶剂条件下所制备的还原氧化石墨烯与聚吡咯复合材料都具有优异的电容性能和良好的稳定性。当水醇比为9∶1(体积比,下同)时,所制备的材料具有最稳定的电容性能。     

石墨烯/聚吡咯复合材料制备及应用研究进展

具有独特二维纳米结构的石墨烯可为电子转移提供通道,使其复合材料具有优良的电容性能。聚吡咯(PPy)因具有超电容性能、聚合电位低和空气稳定性好等优点,常作为理想型电极材料。综述了原位化学氧化聚合法和电化学沉积法2种石墨烯/PPy复合材料的制备方法,以及石墨烯/PPy复合材料在超级电容器、微波吸收、燃料电池催化剂和传感器等电化学方面的应用现状,并展望了石墨烯/PPy复合材料的未来发展方向。     

锂离子电池三维石墨烯基复合负极材料的研究进展

石墨烯具有优异的电学和力学性能以及高比表面积等特点,石墨烯基复合材料在电化学能源中的应用备受关注。构筑三维结构石墨烯基复合材料可以有效提高石墨烯材料的电化学性能。主要介绍了近年来国内外三维石墨烯基复合材料的制备方法及其在锂离子电池负极中的应用,并对其进一步的发展和应用予以展望。     

电化学法制备石墨烯和石墨烯/离子液体复合材料研究进展

石墨烯具有独特的二维结构和优异的光学、电学、力学等性能,一直是纳米材料领域的研究热点之一。石墨烯及其复合材料在超级电容器、锂离子电池、太阳能电池等电化学领域有着诱人的应用前景,高质量、高导电性能石墨烯的制备是石墨烯实际应用的关键问题之一。简述了石墨烯常用制备方法,并着重介绍了电化学法制备石墨烯以及石墨烯/离子液体复合材料,并且对石墨烯研究领域的发展趋势进行了总结和展望。     

石墨烯含量对铝空气电池正极电化学性能影响

以氧化还原法制备石墨烯,通过水合肼还原得石墨烯,通过共沉淀法制备石墨烯/MnO_2复合材料,将所得的复合材料进行SEM和XRD分析,通过电化学性能测试及在铝空气电池中的应用,得出的不同石墨烯含量的石墨烯/二氧化锰的电化学性能,发现含石墨烯50%的GN/MnO_2的复合材料的效果最佳,在20,40,60,80,100和120mA/cm~2的电流密度下放电平台为1.25,1.06,0.95,0.87,0.80和0.76V。     

石墨烯材料的制备及其在电化学领域的应用

石墨烯具有独特的结构和优异的电学、热学、力学等性能,自从2004年被成功制备出来,一直是全世界范围内的一个研究热点.由于石墨烯具有巨大的表面体积比和独特的高导电性等特性,石墨烯及其复合材料在电化学领域中有着诱人的应用前景,因此,石墨烯材料的制备及其在电化学领域应用的研究是石墨烯材料研究的一个重要领域.综述了石墨烯与石墨烯复合材料的制备及其在超级电容器、锂离子电池、太阳能电池、燃料电池等电化学领域中应用的研究现状,展望了石墨烯材料的制备及其在电化学领域应用的未来发展前景.     

氧化石墨烯复合材料在包装领域应用的研究进展

目的整理分析目前国内外氧化石墨烯复合材料在包装材料领域的应用与进展,对未来的发展进行展望。方法归纳整理国内外文献,简单介绍氧化石墨烯的基本性能及制备,氧化石墨烯复合材料的制备,并重点整理分析氧化石墨烯复合材料在包装材料领域的应用与进展。结果氧化石墨烯具有独特的二维纳米片层结构、超大的比表面积和亲水极性界面,通过添加氧化石墨烯可明显改善复合材料的力学性能、阻隔性能、抗菌性能等。结论氧化石墨烯复合材料具有阻隔性高、力学性能好等优点,广泛应用于包装材料领域,并且在抗菌、防腐、阻燃等包装材料领域具有良好的发展前景。     

氟化石墨烯的制备研究进展

新型碳材料氟化石墨烯以独特的物理、化学性能受到广泛关注,在众多领域具有广阔的应用前景。综述了氟化石墨烯的制备方法,主要介绍以氟化石墨为原料的物理剥离法、使用不同溶剂作为插层剂的化学制备方法,以及以氧化石墨烯、石墨烯作为原料的制备方法,总结了各种制备方法的优缺点,并对未来氟化石墨烯的发展前景进行了展望。     

壳聚糖/无机物纳米复合材料在抗菌方面的研究进展

壳聚糖作为一种天然高分子有机物,具有良好的生物相容性、可降解性和抗菌性,在抗菌方面已有一定的应用,但其抗菌性能易受自身因素和外界条件的影响,因此如何巩固和加强壳聚糖的抗菌性能并进行应用成为了研究的热点。将壳聚糖与无机物纳米材料复合,有机和无机组分协同互补,能显著提高材料的抗菌性能,复合材料还具有优异的机械强度和生物相容性,可广泛应用于水处理、食品、纺织、化妆品和医学等领域,引起了科研人员的密切关注。本文总结了壳聚糖的抗菌机理和影响抗菌性能的因素,详细介绍了壳聚糖与金属、金属氧化物、层状硅酸盐和碳材料等无机物复合后的纳米材料在抗菌方面的应用,同时对其在抗菌领域的发展前景进行了展望。     

纤维素/壳聚糖复合材料的制备与应用研究进展

纤维素/壳聚糖复合材料利用纤维素提高了共混材料的力学性能,同时保持了壳聚糖优良的生物相容性和抗菌性,无毒无污染。但是二者分子内和分子间含有大量的氢键,使得在水和常规有机溶剂中很难溶解,限制了复合材料的加工和应用,离子液体的出现为二者的溶解和复合提供了新的思路。综述了纤维素/壳聚糖复合材料的制备方法、制备体系及在工业吸附、生物医疗、食品包装和纺织工业领域的应用,重点介绍了离子液体在此复合材料制备过程中的应用,以为纤维素/壳聚糖复合材料的制备工艺和应用发展提供参考。     

Cell‐Assembled Graphene Biocomposite for Enhanced Chondrogenic Differentiation

Graphene‐based nanomaterials are increasingly being explored for use as biomaterials for drug delivery and tissue engineering applications due to their exceptional physicochemical and mechanical properties. However, the two‐dimensional nature of graphene makes it difficult to extend its applications beyond planar tissue culture. Here, graphene–cell biocomposites are used to pre‐concentrate growth factors for chondrogenic differentiation. Bone marrow‐derived mesenchymal stem cells (MSCs) are assembled with graphene flakes in the solution to form graphene‐cell biocomposites. Increasing concentrations of graphene (G) and porous graphene oxide (pGO) are found to correlate positively with the extent of differentiation. However, beyond a certain concentration, especially in the case of graphene oxide, it will lead to decreased chondrogenesis due to increased diffusional barrier and cytotoxic effects. Nevertheless, these findings indicate that both G and pGO could serve as effective pre‐concentration platforms for the construction of tissue‐engineered cartilage and suspension‐based cultures in vitro.     

纳米羟基磷灰石-胶原蛋白-壳聚糖复合生物材料

采用共沉淀法制备了纳米羟基磷灰石．胶原蛋白．壳聚糖复合生物材料，用IR、XRD、TEM及万能材料实验机等方法对材料性能进行了分析表征。结果表明：羟基磷灰石．胶原蛋白．壳聚糖复合生物材料在晶相组成、化学成分、羟基磷灰石尺寸上具有类骨结构，并具有良好的力学性能．其抗压强度达到128MPa，可满足骨组织修复与替代的要求。有望成为治疗骨缺损的承力替代物。     

The mechanics of graphene nanocomposites: A review

The preparation and characterisation of the different forms of graphene are reviewed first of all. The different techniques that have been employed to prepare graphene such as mechanical and solution exfoliation, and chemical vapour deposition are discussed briefly. Methods of production of graphene oxide by the chemical oxidation of graphite are then described. The structure and mechanical properties of both graphene and graphene oxide are reviewed and it is shown that although graphene possesses superior mechanical properties, they both have high levels of stiffness and strength. It is demonstrated how Raman spectroscopy can be used to characterise the different forms of graphene and also follow the deformation of exfoliated graphene, with different numbers of layers, in model composite systems. It is shown that continuum mechanics can be employed to analyse the behaviour of these model composites and used to predict the minimum flake dimensions and optimum number of layers for good reinforcement. The preparation of bulk nanocomposites based upon graphene and graphene oxide is described finally and the properties of these materials reviewed. It is shown that good reinforcement is only found at relatively low levels of graphene loading and that, due to difficulties with obtaining good dispersions, challenges still remain in obtaining good mechanical properties for high volume fractions of reinforcement.     

Preparation and characterization of novel biodegradable composites based on acylated cellulose fibers and poly(ethylene sebacate)

The preparation and characterization of biodegradable composite materials with improved properties based on poly(ethylene sebacate) (PES) and acylated cellulose fibers is reported. These biocomposites showed improved mechanical properties, as evidenced by the increase in both elastic and Young moduli and in the tensile strength, and also showed low water sensitivity and a high biodegradability rate. These novel biocomposites were prepared essentially from renewable resources and therefore constitute an important contribution to the development of the area of sustainable composite materials.     

A novel and multifunctional flame retardant nucleating agent towards superior fire safety and crystallization properties for biodegradable poly (lactic acid)

In engineering application area, it has always been a challenge to simultaneously improve flame-retardant performance and crystallization rate of polylactic acid (PLA) biomaterials, thus restricting their extensive application. In this work, a multifunctional additive (4,4′-(phenylphosphoryl)bis(piperazine-4,1-diyl))bis(diphenylphosphine oxide) (PDPO) was successfully synthesized and used to fabricate flame retardant PLA biocomposites. The crystallization behavior, fire safety, mechanical properties and flame retardant mechanisms of PLA biocomposites were studied in detail. The results indicated that PDPO notably improved the crystallization rate and crystallinity of PLA biocomposites. When 4 wt% PDPO was incorporated, PLA/PDPO biocomposites successfully passed UL-94V-0 grade and their LOI values were improved from 19.0% of pure PLA to 29.4%. The introduction of PDPO promoted the premature degradation and carbonization of PLA substrate, and inhibited the transesterification of the PLA during thermal pyrolysis process. Besides, PDPO decomposed and produced the Ph and PO, which efficiently exerted the free radical trapping effect in vapor phase. Therefore, the spread of fire for PLA/PDPO was declined and even self-extinguished. Meanwhile, the low addition of PDPO presented little effect on the mechanical properties of PLA composites. This flame retardant PLA biocomposites showed broad application prospects in emerging fields such as electronic devices, automobiles, and 3D printing materials.