生物医用蓖麻油基聚氨酯及其接枝改性的研究进展

蓖麻油是价格低廉的可再生资源,含有大量的羟基,可代替聚酯(醚),合成出蓖麻油基聚氨酯,在生物医学领域有着广阔的发展空间。本文阐述了聚氨酯合成方法,分析了结构特性,并对其蓖麻油基聚氨酯接枝改性进行了较详细的探讨。报道了蓖麻油基聚氨酯接枝改性后的生物医用发展趋势。随着组织修复材料的发展,以天然生物质为原料而制备的该种复合生物材料是有广阔的发展前景。     

提高聚氨酯生物稳定性和相容性的研究进展

聚氨酯因其具有优异的机械性能、良好的生物稳定性和生物相容性等成为目前研究和应用广泛的一种生物高分子材料.但是作为长期植入材料,其生物稳定性和相容性并不完美,因此对聚氨酯材料进行改性来提高其生物稳定性和相容性已成为目前研究的重要方向.本文首先介绍了聚氨酯生物材料的结构特点,概述了其作为生物材料的合成进展情况,然后总结了提...     

负载壳聚糖及其衍生物的材料表面血液相容性研究进展

壳聚糖及其衍生物具有多种生物活性,基于壳聚糖及其衍生物的材料表面改性是获取各种生物活性表面的重要手段,在生物材料领域显示出广阔的应用前景。为了获得血液相容性良好的壳聚糖改性生物材料表面,可通过引入具备抗凝活性的壳聚糖衍生物或壳聚糖/抗凝剂复合物来抑制壳聚糖固有的促凝作用。本文综述了负载有壳聚糖或其衍生物的材料表面的血液相容性改性方法方面的进展,并根据表面改性方法的不同按照物理改性和化学改性分别对其进行了阐述。     

聚多巴胺在生物材料表面改性中的应用

海洋生物贻贝通过其足腺分泌的具有超强黏附性能的蛋白,可在海水等潮湿环境中牢固黏附在各种材料的表面。受此黏附蛋白的启发,研究发现聚多巴胺(PDA)具有类似于贻贝黏附蛋白的结构和超强黏附性能。在碱性条件下,PDA可在各种材料的表面迅速成膜,其中含有大量亲水的羟基和氨基官能团,可提高材料表面的亲水性和化学多功能性;PDA可作为中间层,在基底材料表面强力结合功能分子。由于PDA的形成过程简单且不需要有机溶剂,近年来常被应用于材料的表面改性。此外,由于PDA可促进细胞的黏附,具有良好的生物相容性,在生物材料表面改性中也有较多的应用。本文将综述PDA的黏附机理及其在生物材料表面改性中的应用,并提出PDA在生物材料表面改性应用中的展望及研究过程中存在的问题,为PDA在生物材料和组织工程中的应用提供参考。     

有机硅弹性体表面生物相容性的研究进展

生物材料表面的生物相容性一直是生物材料研究领域倍受关注的问题.本文综述了对有机硅弹性体进行改性以提高其表面生物相容性的研究进展,介绍了各种常用的化学改性方法如本体接枝、等离子体处理、光化学诱导接枝、臭氧活化接枝以及硅氢加成反应、原子转移自由基聚合反应在有机硅弹性体表面改性中的应用.对改性后的有机硅弹性体表面抗非特异性蛋白质和血小板的能力等方面进行了评述,并进一步分析了有机硅弹性体表面化学改性的发展趋势和研究重点.     

有机硅改性聚氨酯的合成与性能

在无溶剂条件下利用二步法合成了一系列氨基硅油改性聚氨酯,采用红外光谱对预聚体进行了表征,同时测试了材料的力学性能、耐热性、表面水接触角及微观形态,结果表明,改性后的聚氨酯具有优良的力学性能、耐热性及表面疏水性,且材料呈微观相分离形态。     

血液相容性及表面改性的研究

血液相容性是生物材料的必要条件 ,本文结合血栓形成的机理 ,综述了改善生物材料血液相容性的主要的几种表面改性方法     

氨乙基氨丙基聚二甲基硅氧烷改性聚氨酯的研究

在无溶剂条件下合成了一系列氨基硅油改性聚氨酯,并对材料的力学性能、耐热性、疏水性及微观形态进行了研究。结果表明：改性后的聚氨酯具有更优良的力学性能、耐热性及表面疏水性,且材料呈微观相分离形态。     

氟改性聚氨酯乳液的合成及其表面性能

氟改性聚氨酯乳液的合成及其表面性能;氟改性;聚氨酯乳液;表面性能     

抗凝血高分子生物材料的表面设计

生物材料,尤其是血液接触材料,满足抗凝血性能是临床应用的首要前提。采用表面改性策略来提高材料表面的抗凝血性能,简单易行。表面改性主要包括表面设计和方法设计两个方面。本文对抗凝血性高分子生物材料的表面设计各类方法进行了综述,其中包括材料表面的微相分离结构、材料的负电荷表面设计、材料的亲(疏)水性表面设计、材料的生物活性化表面设计和材料的内皮细胞化表面设计等等,并重点阐述了两性离子的抗凝血表面设计。     

Renewable epoxidized cardanol‐based acrylate as a reactive diluent for UV‐curable resins

A novel kind of biobased monomer, epoxidized cardanol‐based acrylate (ECA), was successfully synthesized from cardanol via acrylation and epoxidization. The chemical structure was confirmed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance. Then, the ECA was employed to produce UV‐curable films and coatings copolymerized with castor oil‐based polyurethane acrylate. Compared to coatings from petroleum‐based diluent hydroxyethyl acrylate‐based castor oil‐based polyurethane acrylate resins, ECA‐based biomaterials exhibited a little inferior dilution ability but overcome the drawback of high volumetric shrinkage with a special lower value. Moreover, ultimate properties of the UV‐cured biomaterials such as thermal, mechanical, coating, swelling, and hydrophobic properties were investigated. The UV‐curing behavior was investigated using real‐time IR, and the overall double bond conversion was more than 90%. This biobased UV‐curable cardanol‐based diluent shows a promise in “green + green” materials technologies.     

Synthesis and properties of polyurethanes containing phosphatidylcholine analogues in the polymer backbone

New polyurethanes ( 4a, 4b ) and a segmented polyurethane ( 4c ) bearing phosphatidylcholine moieties in the main chain were synthesized. They are thermally stable up to 300°C and show the viscosity behaviour of common polyelectrolytes. Preliminary studies suggest that these polyurethanes are interesting new biomaterials.     

Hydroxyapatite/polyurethane composites as promising biomaterials

The biomaterials are intended to augment or replace the function of tissues or organs in human body. Every year millions of people require soft- or hard-tissue regeneration worldwide. Polymers and their composites are a large class of biomaterials appreciated for tissue regeneration. Polyurethane (PUR) is an organic synthetic multifunctional polymer with established biomedical applications. The hydroxyapatite (HA) is one of the biocompatible ceramic materials similar to natural bone material. The amalgamation of hydroxyapatite with polyurethane enhances the bioactivity of final product along with the combination of individual properties. Here, we review the synthesis, characterization, and applications studies of HA/PUR-based biomaterials. We initiate this review with a brief and representative compilation of the chemical composition and methods of preparation for HA/PUR biomaterials. Then, moving ahead, first, we review the simple HA/PUR biomaterials and use of PUR templates. Second, we review the significance of modified HA and PUR in these biomaterials. Third, we discuss the potential of bio-based PUR and inclusion of third constituent in the HA/PUR biomaterials. Then, we appraise the involvement of trace nutrient in deposition of HA on PUR scaffolds. Finally, we consider the other expedient applications of HA/PUR composites such as drug delivery system and sorbent of pollutants.     

Nouveaux Élastomères de polyuréthanes dérivés d'aminoacides

Synthesis and characterization of new polyurethane elastomers with rigid blocks derived from aminoacids have been achieved by polycondensation using poly(tetramethylene oxide) (PTMO) as a soft segment. Aminotelechelic oligopeptides or pseudopeptides were used in the hard block, eventually in association with lysine diisocyanate (ethyl 2, 6-diisocyanatohexanoate, LDI). Physicochemical characteristics of the so obtained materials, especially good filmmaking properties, allow their use as biomaterials of reduced toxicity.     

一种X-射线不透性聚氨酯显影材料的制备及性能研究

利用对碘苯胺对含有过量异氰酸根的聚氨酯分子进行封端,合成了一种新型的X-射线不透性聚氨酯显影材料.利用X-射线映射对不同封端量聚氨酯的显影效果进行评定;利用DSC和TGA对其热性能进行表征,并评估封端反应对聚氨酯热稳定性的影响;利用噻唑蓝(MTT)比色法测试了材料的细胞毒性;并对具有不同碘含量聚氨酯材料的显影效果、相对分子量及其分布、力学性能进行了对比研究.研究结果表明,当碘含量达到3.5wt%左右时聚氨酯材料即可达到同等厚度铝板相同的显影效果,而且在此条件下,聚氨酯材料依然保持较好的力学性能和热稳定性.MTT法测试表明对碘苯胺封端的聚氨酯材料不具有细胞毒性.     

Synthesis,properties, and fungal degradation of castor-oil-based polyurethane composites with different cellulose contents

Different contents of bonded cellulose were dispersed in a matrix of castor-oil-based polyurethane to produce composites with high susceptibility to fungal attack. We chose to bond the cellulose filler with free diisocyanate, to increase the crosslinking density. Measurements indicated physical and chemical interactions between the polyurethane matrix and cellulose filler. The cellulose network significantly enhanced the interfacial adhesion and thus improved the thermal stability and Young’s modulus of the composites. The influences of the amount of cellulose on the surface chemical structure, surface morphology, and mechanical properties after fungal attack were also investigated. The tensile strength and elongation at break of these composites substantially decreased after exposure to fungus. These composites with high content of renewable raw materials present an optimal balance of physical properties and biodegradability, with potential applications as ecofriendly biomaterials.     

X射线不透性体温固化聚氨酯髓核假体材料的研究

为了制备X光可显影且可以体温固化的聚氨酯,合成了N,N'-双(1,3-二羟基丙基)-2,3,5,6-四碘对苯二甲酰胺(BDTIP)含碘四元醇,将其作为聚氨酯固化的交联剂和X光显影剂,与聚氨酯预聚物混合反应得到一种新的可用于人工髓核假体的材料.利用红外光谱监测BDTIP的反应程度;利用X射线对不同BDTIP含量的聚氨酯材料的显影效果进行评定;利用噻唑蓝(MTT)比色法测试材料细胞毒性,并对具有不同碘含量聚氨酯材料的力学性能进行了对比研究.结果表明,碘的加入对聚氨酯的显影效果有很好的促进作用,较低碘含量(0.2 wt%)的聚氨酯材料即有较好的X光显影效果,而且此时聚氨酯依然保持较好的力学性能;MTT法测试表明含BDTIP的聚氨酯材料不具有细胞毒性.     

Blood compatibility of polyurethane surface grafted copolymerization with sulfobetaine monomer

Surface modification is an effective way to improve the hemocompatibility and remain bulk properties of biomaterials. Recently, polymer tailed with zwitterions was found having good blood compatibility. In this study, the grafting copolymerization of sulfobetaine onto polyurethane surface was obtained through two steps. In the first step, polyurethane film coupled with vinyl groups was obtained through the reaction between the carboxyl group of acrylic acid (AA) and the NH-urethane group of polyurethane by dicyclohexylcarbodiimide (DCC). In the second step, sulfobetaine was grafted copolymerization on the surface using AIBN as an initiator. The reaction process was monitored with ATR-IR spectra and X-ray photoelectron spectroscopy (XPS) spectra. The wettability of films was investigated by water contact angle measurement. The blood compatibility of the grafted films was evaluated by platelet adhesion in platelet rich plasma (PRP) and protein absorption in bovine fibrinogen (BFG). Low platelet adhesion was observed on the grafted films incubated in PRP for 1 and 3 h, respectively. The protein absorption was reduced on the grafted films after incubated in bovine fibrinogen for 2 h. All of these results revealed that the improved blood compatibility was obtained by grafting copolymerization with zwitterionic monomer of sulfobetaine onto polyurethane film. In addition, introducing vinyl groups onto surface through DCC and AA is a novel method to functionalize polyurethane for further modification.     

Synthesis and ESCA surface studies of octadecyl chain-extended polyurethanes

Poly(ether urethane)s as biomaterials display certain favorable mechanical and biocompatibility properties. Earlier studies suggest that improved blood compatibility might be attained by introducing hydrocarbon groups at the surface. We synthesized and characterized a series of polyurethanes in which a N-2,3-dihydroxypropyl-N′-octadecyl urea chain extender (ODCE) was incorporated into the poly(tetramethylene glycol) (PTMO)/4,4′-methylenebis(phenylene isocyanate) (MDI) system. Molecular weights of the polymers varied between 40,000 and 250,000. An electron spectroscopy for chemical analysis (ESCA) study of the ODCE polyurethane surface revealed a substantially enhanced hydrocarbon concentration compared to a control PTMO/MDI/ethylene diamine (ED) polyurethane surface. Also, bulk composition analyses and ESCA data of the ODCE polymers indicated that the percentage of carbon was higher in the surface region than in the bulk. Thus, the ODCE polymer showed a marked increase in hard-segment concentration in the surface region compared to the bulk region and to the ED polymer.     

Modelling the surface free energy parameters of polyurethane coats—part 1. Solvent-based coats obtained from linear polyurethane elastomers

Polyurethane elastomers coating were synthesised by using typical diisocyanates, polyether and polyester polyols and HO-tertiary amines or diols as a chain extenders. Mole fractions of structural fragments (κ _exp) responsible for the polar interactions within polyurethane chains were calculated by ¹H NMR method. Obtained results were confronted with the analogous parameter values (κ _theor) calculated on the basis of process stoichiometry, considering the stage of the production of isocyanate prepolymers and reaction of their extension for polyurethanes. Trials of linear correlation between the κ _exp parameters and surface free energy (SFE) values of investigated coatings were presented. SFE values were determined by Owens–Wendt method, using contact angles measured with the goniometric method. Based on achieved results, another empirical models, allowing for prediction the influence of the kind of polyurethane raw materials on SFE values of received coatings were determined. It was found that it is possible to regulate the SFE in the range millijoules per cubic metre by the selection of appropriate substrates. It has been found that use of 2,2,3,3-tetrafluoro-1,4-butanediol as a fluorinated extender of prepolymer chains is essential to obtain coatings with increased hydrophobicity, applied among others as biomaterials—next to diphenylmethane diisocyanate and polyoxyethylene glycol.