明胶基复合材料及其力学性能表征

发布时间：2018-10-10 08:06

【摘要】：明胶作为一种可降解的生物高分子,因价格便宜、来源丰富无毒、生物相容性好等诸多优点,被广泛的应用于食品、生物与医药等领域。然而明胶较差的力学性能一直掣肘着明胶的实际应用。本文以明胶为研究对象,分别采用了两种纳米粒子以及一种高分子材料为原料与明胶复合,以增强复合材料的力学性能。主要工作主要分为以下三个部分:(1)采用平均尺寸为400 nm的碳模板(OMC)制备尺寸均一的生物活性玻璃。所制备的生物活性玻璃尺寸分布均一,其尺寸大约为300 nm。所制备的生物活性玻璃与明胶复合能够大幅提升明胶的力学性能。所制得的生物活性玻璃具有良好的生物活性,可以有效诱导羟基磷灰石的生成,使得复合材料在生物材料领域具有较大的应用前景。(2)采用冷冻干燥法制备一种可以持续释放药物的载药埃洛石/明胶复合材料。制备的支架具有较为优良的多孔形貌以及物理学性能,埃洛石的加入最大可以将明胶材料的压缩性能提升300%。其力学性能基本满足手术中松质骨的应用要求。明胶/埃洛石的载药体系能最多提供一个100小时的药物释放时间,相较于纯明胶8小时的释放时间以及埃洛石10小时的释放时间有着巨大的提升。能有效缓解病人在手术过程中的痛苦。在细胞实验中,MG 63细胞可以再支架中增殖并依附于支架表面。材料极好的力学性能以及药物缓释能力为其在骨组织工程中的应用打下了坚实的基础。(3)将两亲性嵌段共聚物(PLA-PEG)与明胶材料复合,通过嵌段共聚物中的亲水性基团与明胶相互作用,从而起到增加交联密度从而增强明胶材料屏蔽性能的作用。复合材料的屏蔽性能尤其是水蒸气隔绝性能相较于纯的明胶材料得到了一个巨大的提升,水蒸气透过率相较之于纯明胶材料减少了 67%。少量PLA-PEG的添加就对明胶有一个比较明显的力学增强效果,在PLA-PEG添加量为5%时,复合材料得到最高的屈服强度(55 MPa,相较于明胶提高了 189.4%)和模量(2141 MPa,相较于明胶提升了90.5%)。当PLA-PEG继续加入时,复合膜材料不仅增强了力学性能而且还增强了其韧性。而且,其氧气隔绝性能要远远高于纯的PLA材料且与明胶材料基本相当。材料在自然条件中有一个较为适宜的降解时间。是一种环境友好型的包装膜材料。同时这一降解性质也暗示了其在诸如生物材料的领域的潜在应用前景。PLA-PEG/明胶复合材料具有在食品包装膜材料中具有潜在的应用前景。
[Abstract]:As a biodegradable polymer, gelatin has been widely used in many fields such as food, biology and medicine because of its advantages of low price, abundant and non-toxic sources, good biocompatibility and so on. However, the poor mechanical properties of gelatin have been restricting the practical application of gelatin. In order to enhance the mechanical properties of the composite, two kinds of nano-particles and one kind of polymer material were used as raw materials and gelatin as the research object in this paper. The main work consists of the following three parts: (1) the bioactive glass with uniform size was prepared by carbon template (OMC) with an average size of 400 nm. The size distribution of the bioactive glass is uniform, and its size is about 300 nm.. The composite of bioactive glass and gelatin can greatly improve the mechanical properties of gelatin. The bioactive glass has good bioactivity and can effectively induce the formation of hydroxyapatite. The composite materials have great application prospect in the field of biomaterials. (2) A kind of drug-loaded aloxite / gelatin composite can be prepared by freeze-drying method. The prepared scaffolds have excellent porous morphology and physical properties. The compression properties of gelatin materials can be improved by 300% with the addition of Ellosite. Its mechanical properties basically meet the requirements of the application of cancellous bone in surgery. The drug delivery system of gelatin / aloxite can provide up to 100 hours of drug release time, compared with the pure gelatin release time of 8 hours and the release time of Ellostone 10 hours. Can effectively alleviate the patient's pain during the operation. In the cell experiment, MG63 cells can proliferate in the scaffold and adhere to the scaffold surface. The excellent mechanical properties and drug release ability of the materials laid a solid foundation for their application in bone tissue engineering. (3) Amphiphilic block copolymers (PLA-PEG) were combined with gelatin materials. Through the interaction between hydrophilic groups and gelatin in block copolymers, the cross-linking density is increased and the shielding properties of gelatin materials are enhanced. Compared with the pure gelatin, the shielding performance of the composite, especially the water vapor isolation, is greatly improved, and the water vapor transmittance decreases by 67% compared with that of the pure gelatin. The addition of a small amount of PLA-PEG had an obvious mechanical strengthening effect on gelatin. When the content of PLA-PEG was 5, the composite obtained the highest yield strength (55 MPa, increased by 189.4% compared with gelatin) and the modulus (2141 MPa, increased 90.5% compared with gelatin). When PLA-PEG continues to be added, the composite membrane material not only enhances the mechanical properties but also enhances its toughness. Moreover, its oxygen isolation performance is much higher than pure PLA material and is basically equivalent to gelatin material. The material has a more suitable degradation time in natural conditions. It is an environmental friendly packaging film material. At the same time, this degradation property also indicates that the potential application prospect of PLA-PEG / gelatin composite in the field of biomaterials such as biomaterials has a potential application prospect in food packaging film materials.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB332

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