共查询到18条相似文献,搜索用时 93 毫秒
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《化学推进剂与高分子材料》2015,(4)
<正>中科院青岛生物能源与过程研究所(青岛能源所)生物基材料重点实验室研究员万晓波带领的生物基及仿生高分子团队在聚氨酯材料研究中取得新进展,成功开发出两类新型聚氨酯材料:聚氨酯水凝胶及单组分聚氨酯水固化防水涂料。聚氨酯水凝胶兼具水凝胶和聚氨酯的优点,机械强度高,性能调控范围广,广泛应用于生物医学及工业领域。其中,高保水量、高机械强度的单组分聚氨酯水凝 相似文献
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将2,4-二羟基苯甲醛(DDBA)作为扩链剂,丙烯酸羟乙酯(HEA)作为封端剂制备了含有醛基的水性聚氨酯(DPU),在温和的条件下引入羧甲基化壳聚糖(CMCh)合成了聚氨酯-CMCh席夫碱,再由自由基聚合法引入聚丙酰胺合成了聚氨酯-羧甲基壳聚糖席夫碱水凝胶(DPU-Ch)。通过FTIR、SEM、力学性能、溶胀保水试验、抗菌试验和血液相容性测试等对水凝胶结构和性能进行表征。结果表明,水凝胶的机械性能随着CMCh质量分数的增加而提升,同时水凝胶也显示出良好的溶胀能力和保水能力;当CMCh添加量为2%时,水凝胶对革兰氏阳性和阴性细菌菌株均显示出良好的抗菌性能;水凝胶溶血率均低于5%表明其具有良好的细胞相容性,NIH3T3细胞存活率在90%以上证明其没有细胞毒性,因此在生物医疗领域中具有潜在的应用前景。 相似文献
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温度、pH及离子强度敏感性聚氨酯水凝胶的合成与性能研究 总被引:2,自引:0,他引:2
以甲苯二异氰酸酯(TDI)、聚乙二醇(PEG-6000)、二羟甲基丙酸(DMPA)及三乙撑四胺(TEFA)等为原料,合成了温度、pH、及离子强度敏感性聚氨酯水凝胶(PUHG)。研究了PUHG溶胀率(SR)受温度(T)、pH、离子强度(I)、交联剂用量等因素的影响。结果表明PUHG的溶胀率在20~45℃的范围内随温度的升高而减小,45℃后不再变化;在酸性(pH4)溶液中收缩,在碱性(pH9)溶液中溶胀,表现出良好的pH值敏感性;在一定温度和pH下,随着离子强度的增加PUHG的溶胀率减小。水凝胶溶胀动力学研究表明,PUHG具有良好的溶胀-退胀可逆性。 相似文献
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以聚丙烯酰胺(PAM),聚氨酯(PU)为制备凝胶的基本单元,通过在室温下将线性PAM溶解和分散在水中,添加PU组分,制备出一种合成简便的聚丙烯酰胺/聚氨酯(PAM/PU)水凝胶,并研究了其对Pb~(2+)的吸附性能,探索了吸附的最佳组分,结果表明凝胶在15%(wt)PAM,40 g/L PU吸附效果最好,PAM分子量对凝胶的吸附性能影响较小。 相似文献
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Hydrogels are attractive materials for constructing underwater antifouling coatings on solid substrates. However, the application of hydrogel coatings usually faces the obstacles of complex preparation process and poor durability. Herein, we present a facile method to prepare durable hydrogel coatings on metal foils based on rationally designed supramolecular polyurea (PU) hydrogels. PU hydrogels are designed to be cross-linked with hydrogen bonds (H-bonds) and hydrophobic interactions in the hard segment domains by using dihydrazides with different alkyl spacer lengths ( (CH2)m ) as chain extender. The synergy of H-bond and hydrophobic interaction can stabilize H-bonds in water, as confirmed by Raman spectroscopy. As a result, PU hydrogels exhibit antiswelling capacity and robustness in both deionized water and seawater. Subsequently, PU hydrogel coatings on Cu/Al foils are prepared by convenient brush coating and subsequent swelling. The resulting hydrogel coatings exhibit excellent underwater anti-oil-adhesion and self-cleaning property, and are durable enough to withstand various static and dynamic damaging tests. The good durability of PU hydrogel coatings should be ascribed to the robust adhesion interface and excellent antiswelling capacity of PU hydrogels. The combination of facile preparation and good durability makes PU hydrogel coatings promising candidates for reliable underwater antifouling. 相似文献
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生物医用水凝胶材料的研究进展 总被引:1,自引:0,他引:1
简述了医用水凝胶材料的基本要求,文章主要介绍了生物医用水凝胶材料的优点及研究热点。讨论了水凝胶材料合适的医用范围,预测了医用水凝胶材料的发展方向。 相似文献
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Maria Bercea Luiza Madalina Gradinaru Ioana‐Alexandra Plugariu Mihaela Mandru Daniel Laurentiu Tigau 《Polymer International》2020,69(2):149-155
The rheological behaviour of polyurethane (PU) and poly(vinyl alcohol) (PVA) was investigated in aqueous solution and the hydrogel state. The dependence of viscosity on polymer concentration is discussed. The formation of supramolecular structures induced by temperature increase or shear conditions was evidenced. In PU solutions, as temperature increases, a self‐assembling process occurs due to hydrogen bonding and hydrophobic interactions determining a thermoreversible hydrogel formation. In creep and recovery tests, the weak PU network presents high elasticity only at low shear stress (below 10 Pa); it recovers only 15%–20% of strain above 40 Pa and the hydrogel structure fails at high shear stress (above 150 Pa). Also, PU hydrogel is not able to recover its structure after being submitted to successive low and high deformations. In PVA solutions, a shear induced aggregation was observed at 37 °C. PVA hydrogels obtained by the freezing–thawing method present high elasticity and stability due to the strong polymer–polymer interactions established between the polymer chains. Physical networks based on PU/PVA mixtures synergistically combine the characteristics of the two polymers, showing high elasticity when a shear stress up to 3000 Pa is applied during the creep test followed by a fast recovery of the hydrogel structure after exhibiting successive levels of deformation (self‐healing ability). Therefore, these hydrogels are suitable materials for tissue engineering applications. © 2019 Society of Chemical Industry 相似文献
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The nature of hydrogel polymers is described together with the range of biomedical applications in which their use has been suggested or described in the literature. The field of contact lens materials has provided the greatest variety of synthetic hydrogels and the material requirements for extended wear lenses present problems that are typical of those encountered in biomedical applications in general. The patient literature relating to contact lenses is reviewed and the development of the composition of hydrogel materials is thereby traced and compared with the range of lens materials currently available. In contrast the most commonly encountered, in fact almost the sole, hydrogel material in the literature relating to those areas more conventionally regarded as biomedical, is poly(2-hydroxeythyl methacrylate) or polyHEMA. The use of this and related hydrogels in various applications including prostheses, ocular surgery, sature coatings, artificial internal organs and drug delivery systems is reviewed. 相似文献
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Immobilization of metal nanoparticles on polyurethane membranes: synthesis and electrical properties
Mayur Valodkar Puran Singh Rathore Poonam Sharma Dinesh Kanchan Mehul Patel Sonal Thakore 《Polymer International》2012,61(12):1745-1750
Ag and Cu nanoparticles were immobilized into crosslinked polyurethane (PU) membranes by taking advantage of the swelling characteristics of the membranes. The formation, shape and size of the nanoparticles inside the post‐swollen PU membranes were observed by transmission electron microscopy and atomic force microscopy. X‐ray diffraction indicated the presence of the pure Ag and Cu embedded in the amorphous PU matrix. Because of their compatibility, the nanoparticles improved the thermal stability and increased the glass transition temperature of PU. The membranes exhibited interesting conducting behavior with increasing temperature. The metal immobilization increased the ionic conductivity which further increased with temperature, with an activation energy of 0.15 eV indicating a thermally activated conduction mechanism. The optical and electrical properties of these starch‐based membranes can be utilized in the development of novel sensors for biomedical applications. Copyright © 2012 Society of Chemical Industry 相似文献
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采用聚乙二醇、Ymer N120、聚丙二醇和异佛尔酮二异氰酸酯为原料,以三乙醇胺作交联剂合成聚氨酯(PU)预聚物,浸入白芨多糖(BSP)和丙烯酰胺(AM)混合溶液,通过自由基聚合制备了负载BSP的PU/PAM双网络水凝胶.采用FTIR、SEM对水凝胶的结构和形貌进行了表征,通过拉力试验机和生物实验对其力学性能和生物性能进行了测试.结果表明,当三乙醇胺用量为多元醇物质的量的60%时,双网络水凝胶具有高溶胀率(256%)的同时保持一定的拉伸强度(1.9 MPa)和高压缩强度(22.7 MPa).双网络水凝胶具有抗菌抗氧化作用,其中,双网络水凝胶对大肠杆菌和金黄色葡萄球菌的抑菌带宽度分别为0.5~4.0和0.5~3.5 mm,羟基自由基清除率最高为28%;溶血率低于5%,细胞存活率最高达101.3%±3.6%,表明双网络水凝胶具有良好的生物相容性. 相似文献