交联对CO_2共聚物为基的聚氨酯降解性能的影响

讨论了CO2 共聚物为基的聚氨酯 -聚碳酸亚乙酯聚氨酯 (PEC-PU)交联方式、交联程度对其生物降解性能的影响。实验结果显示 ,交联程度越大 ,降解程度有所降低 ,但一定交联程度的交联型PEC -PU仍然具有良好的生物降解性能。     

基于四重氢键作用的相变保温聚氨酯

以一种新型含四重氢键脲基嘧啶酮单元（2-脲-4[1H]-嘧啶酮,UPy）的二元醇为扩链剂,扩链异氰酸酯基封端的1,6-己二异氰酸酯（HDI）与聚乙二醇（PEG）合成的聚氨酯预聚物,成功合成了含四重氢键单元的相变保温聚氨酯。通过DSC、XRD、黏度测试及拉伸力学性能测试对聚氨酯进行了性能分析。结果表明：该聚氨酯具有较好的...     

赖氨酸乙酯扩链聚氨酯弹性体的制备

以1,6-六亚甲基二异氰酸酯(HDI)为硬段、聚碳酸酯二元醇(PCDL)为软段、赖氨酸乙酯盐酸盐(Lys-OEt)作为扩链剂合成一种新型聚碳酸酯型聚氨酯弹性体.通过力学性能测试、原子力显微镜(AFM)、红外光谱分析和细胞培养,探讨了聚氨酯弹性体软硬段比例、扩链剂对材料性能的影响和材料的细胞毒性.结果表明:随着硬段含量的增加,聚氨酯的机械性能提高.采用Lys-OEt扩链的聚氨酯弹性体拉伸强度达到18.6 MPa,在Lys-OEt、1,4-丁二醇(BDO)、二羟甲基丙酸(DMPA)3种扩链剂中力学性能最佳.初步的细胞培养实验证明,该材料具有良好的细胞相容性.     

软段对水性聚氨酯结构与性能的影响

以低聚物多元醇、异氟尔酮二异氰酸酯(IPDI)、亲水单体二羟甲基丙酸(DMPA),乙二胺为主要原料,制备了一组不同组成的聚氨酯乳液。通过粘度测定、粒度分析、力学性能和耐水性能测试、原子力显微镜(AFM)分析,研究了软段类型、软段分子量对乳液及其胶膜性能的影响。结果表明,分子结构规整、易结晶的软段合成的聚氨酯树脂力学性能和耐水性能都较好,对聚己二酸酯而言,分子量减小,其合成的水性聚氨酯拉伸强度提高,耐水性能却有很大程度的下降。     

含UPy侧链聚氨酯的合成与性能

以二苯基甲烷二异氰酸酯（MDI）和聚四氢呋喃醚二醇（PTMG）合成预聚体,用2-甲基-2-UPy（2-脲-4[H]-嘧啶酮）基-1,3-丙二醇为扩链剂制备了一系列侧链含UPy的聚氨酯。利用FT-IR、1 H-NMR、DMA和力学性能测试等手段对该聚氨酯的结构和性能进行了表征。结果表明：该聚氨酯的力学性能与不含UPy基团的聚氨酯相比有较大的提升;UPy的四重氢键效应形成的物理交联网络结构,使该聚氨酯的玻璃化转变温度随UPy含量的增加向高温方向移动,损耗角正切（tanδ）峰减弱;在宽频的频率场中,随着UPy含量增加,tanδ峰向低频移动,峰强减弱,储能模量增大。     

二氧化碳共聚物为基聚氨酯的生物降解性研究

以ＣＯ２为起始物合成生物降解型聚合物，既能利用丰富的ＣＯ２资源，减轻温室效应；又能减轻聚合物垃圾造成的污染。聚碳酸亚乙酯（ＰＥＣ）经动物体内实验和土埋实验，证明具有良好的生物降解性［１，２］。由ＰＥＣ合成的聚氨酯可获得有良好力学性能的材料，但是否具有...     

丁腈羟平均官能度对固化反应及固化物性能的影响

以过氧化氢为引发剂,加入巯基乙醇或丙烯酸羟乙酯,合成了四种不同官能度的端羟基丁二烯-丙烯腈共聚物。以异佛尔酮二异氰酸酯为固化剂,N,N'-二羟丙基苯胺为链延伸剂,制得一系列多嵌段聚氨酯弹性体,研究了平均官能度对固化反应速度及固化物力学性能、动态力学性能、热性能和耐油性能的影响规律。     

组织工程用聚氨酯的研究进展

聚氨酯具有良好的生物相容性、优异的力学性能、易成型加工、性能可控等优点，这使它在组织工程中有广泛应用。本文讨论硬段、软段、扩链剂的选择对组织工程用聚氨酯的性能和微相分离影响，并展望了组织工程用聚氨酯的发展方向。     

聚氨酯与乙酰丙酮铽复合物的相互作用

合成了聚氨酯、乙酰丙酮铽及其复合物. 红外光谱研究结果表明, 铽离子与聚氨酯分子链中的羰基发生了配位作用. 力学性能测试结果表明, 稀土配合物的加入提高了聚氨酯的拉伸强度和断裂伸长等力学性能. 流变性能测试结果显示, 乙酰丙酮铽的加入使聚氨酯溶液的粘度增大, 表明溶液中两者之间存在明显的相互作用.     

聚氨酯弹性体力学性能影响因素探讨

研究了合成方法、原料的种类与配比、硫化工艺条件等因素对聚氨酯弹性体力学性能的影响。结果表明,聚氨酯弹性体的结构与组成以及由此引起的微相分离程度的变化是影响弹性体性能的重要因素。对于同样的聚合多元醇、二异氰酸酯及扩链剂合成的弹性体,采用不同的硫化及熟化条件其力学性能不同,并找到达到最佳力学性能所需的工艺条件。     

Polyurethanes: Versatile Materials and Sustainable Problem Solvers for Today’s Challenges

Polyurethanes are the only class of polymers that display thermoplastic, elastomeric, and thermoset behavior depending on their chemical and morphological makeup. In addition to compact polyurethanes, foamed variations in particular are very widespread, and they achieve their targeted properties at very low weights. The simple production of sandwich structures and material composites in a single processing step is a key advantage of polyurethane technology. The requirement of energy and resource efficiency increasingly demands lightweight structures. Polyurethanes can serve this requirement by acting as matrix materials or as flexible adhesives for composites. Polyurethanes are indispensable when it comes to high‐quality decorative coatings or maintaining the value of numerous objects. They are extremely adaptable and sustainable problem solvers for today’s challenges facing our society, all of which impose special demands on materials.     

Synthesis of polyurethanes from fluorinated diisocyanates

A number of polyurethanes based on fluorinated aliphatic diisocyanates, perfluorinated aromatic diisocyanates, and chlorinated aromatic diisocyanates have been prepared. The polyurethane prepared from perfluorotrimethylene diisocyanate and hexafluoropentanediol was a rubbery solid which hydrolyzed readily in air to a liquid or sticky solid but was stable if protected from moisture. The products of hydrolysis were isolated and identified. Polyurethanes based on hexafluoropentamethylene diisocyanate were synthesized by reaction of hexafluoropentanediamine with hexafluoropentamethylene bischloroformate and with tetrafluoro-p-phenylene bischloroformate. Polyurethanes were synthesized by reaction of tetrafluoro-p-phenylene diisocyanate with hexafluoropentanediol and pentanediol. Other perfluoroaryl diisocyanate-based polyurethanes were synthesized by reaction of tetrafluoro-m-phenylene diisocyanate with hexafluoropentanediol and with tetrafluoro-p-hydroquinone. Polyurethanes were also synthesized by reaction of tetrachloro-p-phenylene diisocyanate and 2,3,5,6-tetrachloro-p-xylylene-α,α′-diisocyanate with hexafluoropentanediol.     

Novel copolyesters based on poly(alkylene dicarboxylate)s: 1. Thermal behavior and biodegradation of aliphatic-aromatic random copolymers

In order to improve the thermal and mechanical properties of the poly(butylene 1,12-dodecanedioate), some novel aliphatic-aromatic random copolyesters have been prepared by starting from 1,4-butanediol and different molar ratio of 1,12-dodecanedioc acid and terephthalic acid. The samples were characterized by ¹H NMR and the molecular structure was correlated with the crystalline phase present, the level of crystallinity, the glass transition temperature, the mechanical behavior, and the biodegradability. In particular, the copolymer containing the 70 mol% of PBT repeating units notably improves the thermal and mechanical properties of the poly(butylene 1,12-dodecanedioate) towards those of PBT and maintains a very high thermal stability, but loses the biodegradability of the poly(alkylene dicarboxylate). Therefore, for this class of aliphatic-aromatic copolymers the chemical composition must be carefully chosen to reach a compromise between good thermal and mechanical performances and biodegradability, according to the necessity.     

Synthesis and degradation of nontoxic biodegradable waterborne polyurethanes elastomer with poly(ε-caprolactone) and poly(ethylene glycol) as soft segment

In this study, in order to obtain waterborne polyurethanes (WBPUs) with biocompatibility, biodegradability as well as good mechanical properties, a series of nontoxic cross-linked waterborne polyurethanes were designed and synthesized with isophorone diisocyanate (IPDI), poly(ε-caprolactone) (PCL), poly(ethylene glycol) (PEG), 1,4-butandiol (BDO) and l-lysine without any other organic agent involved in the whole synthetic process. The bulk structures and properties were characterized by DSC, IR and Instron, mainly focused on the effect of amount of PEG. Their corresponding biodegradability was examined with Lipase AK. The result showed that the prepared waterborne polyurethanes had very good tensile properties, allowing them to be well used as biomaterials. And the change of tensile properties with increasing of amount of PEG in the polymers could be assigned to the change of microphase separation, as indicated by DSC and IR data. A quite good biodegradability was achieved as judged from the change of tensile properties as a function of time. The current work demonstrated a new synthetic approach that can be more promising to prepare both nontoxic and biodegradable polyurethanes for soft tissue engineering applications or drug delivery.     

Study on the Synthesis and Biodegradation of Aliphatic Polyester

With the increasing use of one-off plastic products, the environmental pollution resulted from the plastic waste has become more and more serious. So many scientists have focused their attention on developing biodegradable polymers to substitute the traditional unbiodegradable polymers in the manufacture of disposable products. Thus the plastic waste can be treated by landfill or composting technique. It has been found that aliphatic polyesters possess better biodegradability compared with oth…     

Synthesis and study of polyurethanes and polyurea urethanes based on the diamino derivatives of bis-1,3,4-oxadiazole

Polyurethanes were synthesized by condensation of diamino derivates of bis-1,3,4-oxadiazole with chloroformates, and polyurea urethanes were synthesized from diamino derivaties of bis-1,3,4-oxadiazole, diisocyanates, and ethylene glycol in a solution of dimethylformamide. Certain properties of these compounds were studied.     

温敏性聚膦腈及其在药物释放体系中的应用

温敏性聚合物能通过感知温度而实现环境响应,作为药剂可依靠对此类信号的自反馈响应而释放药物或中止释放,极大地增强了释药的持续性和专一性,从而提高了药物的药效和安全性.温敏性聚膦腈是一类新型的温敏材料,它具有良好的生物可降解性质,优良的生物相容性.因此,温敏性聚膦腈作为药物载体用于药物释放体系具有很好的应用前景,近年来备受关注.本文对聚膦腈的温敏性质、生物降解性质进行了评述,并探讨了LCST的影响因素,以及在药物释放体系的应用进展.     

含液晶二醇聚氨酯研究

合成了具有液晶性质的二元醇一对苯二甲酰二羟苯甲酸丁二醇酯（ＴＯＢＢ），这种二元醇单独或与端羟基聚了二烯（ＨＴＰＢ）混合后与二异氰酸酯反应生成几种聚氨酯，用ＩＲ，ＤＳＣ，偏光显微镜和ＷＡＸＤ对它们进行了表征，证明这种二元醇和聚氨酯都具有液晶性质。     

生物降解脂肪族不饱和聚酯碳酸酯 2.生物降解

土埋法显示脂肪族不饱和聚酯碳酸酯(AUPEC)有良好的生物降解活性,单位面积失重(WPA)为其生物降解性能的较好指标,土埋三个月,AUPEC的WPA可达55mg·cm~(-2),失重达0.15质量分数,此外,实验表明生物降解主要在ALPEC的表面进行,聚合物的特性粘数、链结构、玻璃化转变温度及热分解温度不随聚合物的降解失重而变化。