【作者】 杜民慧；

【导师】 钟银屏；

【作者基本信息】 四川大学 ， 生物医学工程， 2003， 硕士

【摘要】 防水可呼吸性是指聚合物薄膜及涂层不允许水滴透过，同时却要保证水蒸汽分子自由透过，达到防水可呼吸的目的。这类材料生产的衣物，鞋袜等既可起到防水的作用，又避免了传统的恶劣环境用衣物产生的闷热，冷湿等不适的缺点。根据防水可呼吸的原理不同，该材料可分为三类：微孔型、亲水型和形状记忆型。微孔型是通过控制孔径的大小来达到防水可呼吸的目的；亲水型是无孔膜，主要通过材料中的亲水基团对水蒸汽分子的吸附-扩散达到防水可呼吸的目的；形状记忆型是通过控制聚合物材料的玻璃化转变温度来达到相同的目的。后两种为无孔结构可起到防菌的作用，同样微孔型通过控制微孔的大小也可起到防菌的效果，因此这类功能型材料在医疗方面的应用也越来越广，可用于伤口敷料、外科手术服及保护性衣物、医用手套等，形成了一个富有挑战性的研究领域。 用于制备防水可呼吸薄膜及涂层的聚合物材料大都是AB型嵌段聚合物，如嵌段共聚醚酯(PEE)、嵌段共聚醚胺(PEBA)和聚氨酯(PU)等，其中以聚氨酯的机械性能和生物相容性更为优越，被广泛地作为医疗制品制备的主要原料。 为了获得更高的可呼吸性能，本论文结合微孔型和亲水型薄膜及涂层的可呼吸原理，在制备微孔膜的聚氨酯原料中引入了亲水性很好的聚乙二醇作为软段。但是为了避免由单一聚乙二醇合成的聚氨酯对水敏感而发生膨胀的缺点，在软段中还引入了机械韧性很好且不易发生膨胀的聚四氢呋喃醚，通过两种组分的混合，有效地发挥各自的特点，达到平衡物理性能的作用。 本论文采用两步法合成了以4，4’一二苯基甲烷二异氰酸酷(姗I)、l，4-丁二醇为硬段，聚乙二醇(PEG)和聚四氢吠喃醚(PTMG)为混合软段的聚醚型聚氨酷。应用傅立叶变换红外光谱(FTIR)、示差扫描量热技术(DSC)来研究材料的微观结构，结果表明本论文合成的聚氨醋软硬段的相容性得到了很大的提高，这有助于材料的可呼吸性能的增加。力学性能测试、水接触角和吸水率测试表明，运用PEG和PT游混合软段合成聚氨酷具有较高的力学性能，同时还具有较好的亲水性，它对提高材料的可呼吸性有很大的帮助。溶血试验和静态血小板粘附试验表明，由于亲水基团的引入是材料表面血小板粘附率降低，具有良好的抗血小板豁附能力。 在上述PU材料合成的基础上，本论文还探索了防水可呼吸聚氨酷微孔膜的制备。分别从聚氨酷原液浓度、沉淀浴浓度和浸泡时间三方面对成膜工艺进行了讨论，并对微孔膜的可呼吸性、力学性能和防水性能进行评价。结果表明，试验制得的聚氨酷微孔膜孔径蕊2.5 pm，且分布比较均匀，符合微孔膜的要求。并且，微孔膜的水蒸汽透过率大大高于无孔膜，可呼吸性能增加，但防水性能有所下降。更多还原

【Abstract】 Waterproof and breathable polymer film and coatings are permeable to water vapour molecules and not to permit water droplets to penetrate through them. Garments coated with these film and coatings not only are waterproof but reduce the build-up of moisture vapour emitted from the body as perspiration inside the taditional foul-weather clothing, which leads to an increasing sense of discomfort. Based on the mechanism of waterproof and breathability , this kind of polymer film and coatings can be classified into three types: micropore, hydrophilicity and shape-memory polymer film and coatings. By adjusting the size of pore, microporous film and coatings can achieve waterproof and breathability. Hydrophilic ones are nonporous and can transport water vapour molecules by molecular diffusion (according to the sorption-diffusion model) through the polymer matrix. The last ones can also get the same properties through adjusting the class transition temperature of polymer. Because this kind of film and coatings can also serve as a barrier membrane to dust or pathogens, they are finding increasing use in medical field, such as wound dressing, multiple-use protective garments and medical glove and so on, which present a specially interesting challenge.Polymer used for waterproof and breathable film and coatings aremainly multiblock copolymers of AB type, Block-copolyether-ester(PEE), Block-copolyether-amide(PEBA) and Polyurethane(PU) etc.. Among them, polyurethane is more preferable.In order to achieve better breathability, blends of Polyethylene glycol (PEG) and Poly(tetrahydrofuran)(PTHF) are used to banlance physical properties. PEG is more hydrophilic, while PTHF is mechanically tougher and does not swell as much.In this paper, a series of polyether-based thermoplastic polyurethanes were synthesized with 4,4’ -diphenylmethane diisocyanate(MDI), 1,4-butanediol(BDO) as hard segment and poly(tetrahydrofuran)(PTMG) and polyethleneglycol(PEG) as soft segment by the method of bulk two-step process. Fourier transform infraned spectroscopy (FTIR) and differential scanning calorimetry (DSC) are used to characterize their structure. The results show that compatibility between hard and soft segment is increased, which is helpful for improving breathability. Mechanical properties, water contact angles and water adsorption tests reveal that different soft segments have significantly efficacy to optimize the physical properties. This kind of polyurethanes not only possesses good mechanical properties but has good hydrophlicity. Blood compatibility is mainly determined by the hemolysis test and platelet adhesion test. The ratio of platelet adhesion on this material becomes lower because there are more hydrophlic groups in its composition, which contributes to its better blood compatibility.Furthermore, the preparation process of waterproof and breathable polyurethane microporous film was presented in this paper, which was based on three aspects, such as polyurethane concentration, precipitant bath composition and immersion time. Mechanical property, waterproofness and breathability of the microporous films were tested. The results indicate that the average diameter of the pore is about 2. 5 microns orIVless, and the pore is uniformly distributed. The Water Vapour Transmit rate(WVT) of microporous films is higer than the corresponding nonporous films, and the waterproofness declines correspondingly.更多还原