国外聚氨酯热塑性弹性体新进展

本文对我国外聚氨酯热性弹性将发展的历史沿革，目前主要品种，大制造公司，所用原料，生产方法，成品性能，应用范围和发展方向作一简介。     

热塑性聚氨酯弹性体的合成与应用

一、前言热塑性聚氨酯弹性体(简称TPU)是1958年由B·F.Goodrich公司首先开发的。此后,由于它具有高強度、高耐磨、耐屈挠及耐寒性等优异性能而被人们所认识,因此,其用途日渐广泛,产量逐年递增。TPU的主要生产厂家集中在西欧、日本和     

热塑性聚氨酯弹性体的发展

简单介绍了热塑性聚氨酯弹性体的合成、性能及其在共混、补强、互穿网络等方面的最新发展。     

聚氨酯热塑性弹性体的应用开发

１何谓热塑性弹性体 热塑性弹性体（ＴＰＥ）是近二十年来受人关注而获得很快发展的一种高分子合成材料,它既有硫化橡胶的应力应变特性——形变随应力的消失而迅速消除,又有热塑性塑料的加工特性——在力与热的作用下能反复熔融流动,制品不经硫化而呈现橡胶的弹性。不论何种热塑性弹性体其分子结构均由“软段”和“硬段”两部分组成。所谓“软段”是指柔软的线型长分子链,它使ＴＰＥ具有一定的弹性形变;“硬段”是指较短的刚性链,它使ＴＰＥ具有一定的刚性和耐热性。所以也可以说热塑性弹性体是介于硫化橡胶和热塑性塑料之间的一种高…     

热塑性聚氨酯弹性体的加工及其应用

简略介绍了热塑性聚氨酯弹性体的加工方法、加工工艺及其应用领域。对热塑性聚氨酯制品的缺陷和产生的原因进行了分析，并提出了一些可能解决的办法。     

热塑性聚氨酯弹性体与塑料的共混体系

本文简述了热塑性聚氨酯弹性体(TPU)与聚氯乙烯(PVC)、聚甲醛(POM)和聚碳酸酯(PC)的共混工艺以及共混物的物理机械性能。结果表明,TPU/PVC、TPU/POM、TPU/PC共混物的性能优异,极具发展潜力。     

热塑性聚氨酯弹性体的应用浅谈

简要介绍了热塑性聚氨酯弹性体的合成方法,着重介绍了国内外应用方面的研究动向,并在合成与应用方面提出了建议。     

热塑性聚氨酯弹性体与乙华平橡胶共混物的性能

将聚酯型和聚醚型聚氨酯弹性体(TPU385E,TPU8685)分别与不同乙酸乙烯酯含量的乙华平橡胶(EVM400,EVM700)进行共混,考察了原料种类、共混比对共混物力学性能和耐磨性的影响。结果表明,随着TPU用量的增加,EVM/TPU共混物的拉伸强度、邵尔A硬度、100%定伸应力和300%定伸应力均提高,扯断伸长率下降;随着EVM用量的增加,EVM/TPU共混物的拉伸强度、邵尔A硬度、100%定伸应力和300%定伸应力均降低,扯断伸长率增大;随着TPU用量的增加,EVM/TPU共混物的耐磨性提高;TPU8685/EVM400共混物具有最大的拉伸强度,TPU385E/EVM700共混物具有最大的扯断伸长率,TPU8685/EVM700共混物具有最好的耐磨性;当2种TPU与EVM400质量比都为50/50时,TPU385E/EVM400的耐磨性最差。     

热塑性聚氨酯弹性体粘合剂的制备及力学性能的研究

以环氧乙烷—四氢呋喃无规共聚醚(PET)、异佛尔酮二异氰酸酯(IPDI)和1,4-丁二醇(BD)为原料,采用预聚法(二步法)合成热塑性聚氨酯弹性体(TPU)粘合剂。确定预聚温度为700C,反应温度为1000C,以及预聚反应时间为1.5～2.0小时。通过调整硬段、软段含量对TPU的性质进行优化,获得用于含能材料的粘合剂。通过凝胶渗透色谱(GPC)分析和力学性能测试对所合成的TPU进行表征。测试结果表明,随着硬段含量的增加,TPU的拉伸强度不断增大,断裂伸长率则降低。当硬段含量在45%～55%时TPU的综合性能达到最佳。     

热塑性聚氨酯弹性体力学性能和结晶性能的研究

采用预聚法合成聚氨酯弹性体,分别对预聚反应的时间、温度进行了考察,确定了合适的反应条件。讨论了软段的种类和数均相对分子质量对其结晶性能的影响,采用DSC和WAXD对弹性体的结晶性能和微相分离进行了分析,并对软段结构、扩链剂的类型、异氰酸酯的结构和助剂等进行了研究,结果表明,弹性体的结晶性能随软段结晶性的增加和数均相对分子质量的增大而增强,力学性能随软段结晶性的增强而增加,随扩链剂和异氰酸酯结构不同而差别较大,适当添加助剂对弹性体性能有补强作用。     

硅橡胶/聚氨酯热塑性弹性体的制备

采用过氧化物硫化体系制备了硅橡胶(VSR)与聚氨酯(TPU)质量比为50/50的VSR/TPU热塑性弹性体。考察了VSR的硫化条件,研究了抑制剂4-羟基2,2,6,6-四甲基哌啶氧(TEMPO)用量对VSR/TPU体系动态硫化过程及性能的影响。结果表明,当Hakke流变仪转速为110 r/min、硫化温度为180℃、硫化剂2,5-二甲基-2,5双(过氧化叔丁基)己烷用量为1.0份(质量,下同)、抑制剂TEMPO用量为0.3份时,制备的VSR/TPU热塑性弹性体具有较精细的相态,分散相VSR在TPU连续相中分散较均匀,热塑性弹性体的拉伸强度及扯断伸长率分别达到4.4 MPa及291%,流变性能较好,压缩永久变形最小。     

Tensile and heat resistance behavior of modified thermoplastic polyurethane elastomer in anisotropic neodymium-iron-born bonded magnet

The emergence of anisotropic neodymium-iron-boron (NdFeB)-bonded magnets with high energy density and freedom of shape design is effective in minimizing the dimensions and mass of electric motors. However, limitations in mechanical strength and heat resistance at elevated temperatures hinder their further application. To overcome these challenges, we present a novel approach to enhance the tensile strength and heat resistance of the NdFeB-bonded magnet involving the modification of thermoplastic polyurethane (TPU) through the melt-mixing method with a styrene–acrylonitrile-glycidyl methacrylate terpolymer (SAG) modifier and engineered TPU was then employed in fabricating NdFeB-bonded magnets via calendering molding. The microstructure of the magnets exhibited aligned NdFeB particles due to mechanical stress during calendering molding, which results in anisotropy. Interestingly, the magnetic properties of bonded magnets based on modified TPU remain almost the same compared to their unmodified counterparts, showcasing a maximum energy product of around 12 MGOe. The mechanical tests demonstrated a maximum 32.4% increase in the tensile strength of bonded magnets based on modified TPU. A progressive shift to a higher temperature (100 to 120°C) of magnet samples fractured occurs in the heat resistance measurement of the bonded magnets based on modified TPU, meaning improvement in heat resistance of NdFeB bonded magnets.     

硬段对热塑性聚氨酯弹性体结构及性能的影响

以实验室自制聚己二酸乙二醇酯二醇PEA为软段,二苯基甲烷-4,4’二异氰酸酯(MDI)为硬段,分别采用乙二醇(EG、1,4-丁二醇)、BOD和1,6-己二醇、HG为扩链剂,经预聚体法合成了硬段不同的聚氨酯弹性体。研究了硬段结构和硬段含量对弹性体硬度及力学性能的影响。采用旋转流变仪研究了弹性体在降温条件下的非等温结晶过程。结果表明,当硬段含量相同时,BDO-TPU结晶性能最好,拉伸强度最大;HG-TPU断裂伸长率最好。在BDO-TPU体系中,随硬段含量增加,材料硬度和强度增加,伸长率减小;结晶起始温度逐渐增大,结晶性能增强。     

耐水性水性聚氨酯合成工艺研究

选用聚醚多元醇与聚酯多元醇进行复配,制得耐水性较好的WPU。以DMBA作为亲水扩链剂,探讨了DMBA加入方式以及聚氨酯自乳化方法对水性聚氨酯外观、稳定性、成膜性能的影响。     

MDI基热塑性聚酯型聚氨酯弹性体性能的研究

以4,4′-苯基甲烷二异氰酸酯（MDI）、聚己二酸丁二醇酯二醇（PBA）、1,4-丁二醇（BDO）为原料,采用一步法合成热塑性聚氨酯弹性体（TPU）。在n（—NCO）/n（—OH）（R值）恒定条件下,研究了PBA相对分子质量、BDO添加量与TPU性能关系,并由红外光谱、热重、X射线衍射分别表征了TPU的结构、热性能和结晶特性。研究发现：R值、BDO量和MDI量恒定时,PBA的相对分子质量越高,TPU的拉伸强度、断裂伸长率均呈增加趋势;R值恒定,以相对分子质量3 000的PBA为原料,TPU的拉伸强度、断裂伸长率均随BDO添加量的增加而增加;TPU的热分解温度高于300℃,结晶特性显著。     

Relationship between structure and dynamic mechanical properties of thermoplastic polyurethane elastomer containing bi-soft segment

In this work, we investigated the microphase separation, mechanical, and dynamic mechanical properties of thermoplastic polyurethane elastomers (TPUs) with one-soft segment (polypropylene glycol, PPG, or hydroxyl-terminated polybutadiene, HTPB) or bi-soft segment (PPG and HTPB) using FTIR, XRD, SAXS and amplitude modulated-frequency modulated viscoelastic mode of AFM (AM-FM mode AFM) methods. The results showed that the microphase separation process of hard and soft segments (HS and SS) in TPU containing PPG and HTPB soft segments (PPG-HTPB-PU) was restricted by randomly alternated bi-soft segments, which results in formation of a low content of irregular-shaped hard domain (HD). In addition, the microphase separation of PPG-HTPB-PU induced a triple-phased structure of HD, HTPB rich phase and mesophase. The mesophase of PPG-HTPB-PU was formed of HS, PPG and HTPB segments which were excluded out of HD and HPTB rich domains during microphase separation process. The damping temperature range (at tan δ greater than 0.3) of PPG-HTPB-PU was from −14.6 to 32.1°C (46.5°C) which was more broad than that of TPU containing HTPB soft segment (HTPB-PU). The broad damping temperature range of PPG-HTPB-PU is mainly attributed to the enhanced energy consumption caused by the frictional motions of mixed segments of mesophase.     

Impact modification of polyacetal by thermoplastic elastomer polyurethane

The main goal of this study was impact modification of polyacetal [polyoxymethylene (POM)] with thermoplastic elastomer polyurethane (TPU). We modified the impact strength of POM 10‐fold. The mechanical properties, thermal behavior, and morphology of POM/TPU blends consisting of 5 to 50% of TPU were studied. It was found that the best impact modification of the blends was at 15% concentration of TPU and the maximum elongation at break was at 30% concentration of TPU. The impact strength of POM/TPU blends can be improved by using diphenylmethane diisocyanate (MDI) as compatibilizer. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2573–2582, 2002