交联聚酸酐/针状HAp纳米复合生物可降解矫形材料
文献类型：学位论文
| 作者 | 李浩莹 |
| 学位类别 | 博士 |
| 答辩日期 | 2001-07 |
| 授予单位 | 中国科学院研究生院 |
| 导师 | 谢裕生 ; 陈运法 |
| 关键词 | 纳米复合 生物降解 羟基磷灰石 交联聚酸酐 |
| 其他题名 | Biodegradable nanocomposite of crosslinking polyanhydride/needle-like Hap for orthopedic use |
| 学位专业 | 材料化工 |
| 中文摘要 | 该文选用表面溶蚀性的新型生物降解材料聚酸酐，来替代初始机械强度低且与填充相复合性能不确定的聚酯类材料，以用于矫形材料的制备.通过合成两种新型的酸酐单体：碳碳双键必度高、聚合后亲水性能好的甲基丙烯酸酐化的柠蒙酸（MCA）和能形成疏水性聚合物的甲基丙烯酸酐化的1，4-双（对-羧基苯氧基）丁烷（MCPB），使得交联聚酸酐的力学性能得以提高、降解性能得到改善;通过超声分散原位聚合技术实现了针状羟基磷灰石与交联聚酸酐的纳米复合，有效提主邮交联聚酸酐的力学强度;通过光快速引发和热处理联合操作可大幅度提高酸酐单体的转化率.謂115L票赋鼍哂斜砻嫒苁葱浴⒓嬗懈咔慷群土己萌托浴⒃谀擅壮潭壬暇确稚⒌恼胱呆腔谆沂?交联聚酸酐纳米复合骨折内固定材料. |
| 英文摘要 | The most commonly used degradable polyesters for fracture fixation have low initial mechanical strength. In order to increase the mechanical strength of polyester, hydroxyapatite (HAp) micron particles have been used. But they can not be dispersed homogeneously in the composite and often cause the mechanical strength of the composite to be changed uncertainly. In the present research, surface erosion poly anhydrides have been chosen as an alternative to be used in orthopedic field. Through synthesizing the methacrylated citric acid (MCA) with the increased functionality and hydrophilicity, and through preparing the hydrophobic methacrylated 1, 4-bis(p-carboxyphenoxy) butane (MCPB), the mechanical strength of erosslinking polyanliydrides have been improved and the degradation rate of the poly anhydrides can be controlled in a broad range. The nano-sized needle-like HAp can increase the mechanical strength of erosslinking polyanhydrides remarkablely and can be dispersed homogenously at the nano-scale in the polyanhydrides by using ultrasonic treatment and in-situ polymerization. The combined operations of photopolymerization and heat treatment can enhance the conversion of the anhydride monomers. In a word, the HAp/crosslinking polyanhydride nanocomposites, possessing high strength and good tenacity, undergoing surface degradation, and demonstrating homogeneous distribution of HAp needles in the polymer, have been prepared and shown a great potential in the orthopedic field. In this paper, the experimental results can be summarized as follows: (1) In the hydrothermal preparation of needle-like HAp particles, the dispersant A-611 4- has been used to homogenize HAp needles and decrease their length from about 1 OOOnm to approximately 80nm at pHll.O with the aged temperature 150°C and the aged time 20h. (2) Two novel anhydride monomers have been synthesized. Firstly, the synthesized methacrylated citric acid (MCA) with the increased monomer functionality and a lot of hydroxy can result in high crosslinking density with a concomitant increase in modulus and an improved hydrophilicity of the polyanhydride. Secondly, the methacrylation of 1,4-bis(p-carboxyphenoxy) butane (MCPB) has been carried out to prepare a hydrophobic polyanhydride. These two anhydride monomers can adjust the biodegradable rate of polyanhydride in a broad range. In addition, the methacrylation of sebacic acid (MSA) and pyromellitylimidoanaline (M(PMA-ala)) has been developed. The reaction conditions of all anhydride monomers are optimized, and their chemical structures are illustrated by spectrum analysis. (3) The ultrasonic treatment and in-situ polymerization have been accepted to homogenize the distribution of HAp needles in the crosslinking poly anhydrides, and the mechanical strength of HAp/polyanhydride nanocomposites can be increased dramatically. The mechanical strengths of nanocomposites prepared by HAp needles and crosslinking polyanhydrides are described as follows: As the raising of HAp content in the polyanhydride, the mechanical strength of the HAp/polyanhydride is increasing. The nanocomposites of HAp/PMCA(30%), HAp/PMA(30%), HAp/PM(PMA-ala)(20%),HAp/PMCPB(30%) and HAp/PMSA(20%) have excellent mechanical strength, and the scales of compressive strength, compressive elastic modulus, fluxural strength and fluxural elastic modulus are 41~278MPa, l.l~9.8GPa, 48~278MPa, 5.8~52GPa respectively. Each of them is 2~4 times that of the corresponding polyanhydride itself. At the same content of HAp in the polyanhydrides, the mechanical strength of the nanocomposite is on the order of HAp/PMCA>HAp/PMA>HAp/PM(PMA-ala) HAp/PMCPB>HAp/PMSA. (4) In similar body fluid, the degradation of HAp/polyanhydride nanocomposites can be summarized as follows: The degradation rates of different polyanhydrides were dependent on their moleculare structure. The degradation rates of different polyanhydrides is on the order of PMSA>PMCA>PMA>PM(PMA-ala)>PMCPB. In any case, when the mass loss of each polyanhydride was about 50%, it can retain its 70% compressive elastic modulus. HAp needles can effectively inhibit the degradation rate of polyanhydrides. In contrast with polyanhydride themselves, the decrements of mass loss of nanocomposites HAp/PMCPB(30%), HAp/PM(PMA-ala)(20%), HAp/PMCA(30%), HAp/PMSA(20%), HAp/PMA(30%) are 7%, 15%, 23%, 14% and 14%, and the increments of compressive elastic modulus retention are 4%, 5%, 12%, 15% and 12% respectively during the investigated biodegradation time. |
| 语种 | 中文 |
| 公开日期 | 2013-09-26 |
| 页码 | 161 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/1909]  |
| 专题 | 过程工程研究所_研究所（批量导入） |
| 推荐引用方式 GB/T 7714 | 李浩莹. 交联聚酸酐/针状HAp纳米复合生物可降解矫形材料[D]. 中国科学院研究生院. 2001. |
入库方式： OAI收割
来源：过程工程研究所
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