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1.
以二官能度端氨基聚氧化丙烯和异佛尔酮二异氰酸酯(IPDI)为原料,合成了异氰酸根封端的聚脲预聚体,再用硅烷偶联剂KH550对预聚体进行封端,制备了硅烷封端聚脲。用红外光谱、热重分析、差示扫描量热分析、拉伸强度、吸水率、静态水接触角等手段对材料的结构和性能进行了表征,并讨论了NCO与胺基的摩尔比(R值)对材料性能的影响。结果表明,经过封端改性后,聚脲的力学性能、热稳定性、耐寒性和耐水性得到明显提高,R值为1.05时拉伸强度达4.14MPa,断裂伸长率为420%,在去离子水中放置96h吸水率仅为2.72%,静态水接触角达到78.2°。  相似文献   

2.
以二官能度端氨基聚氧化丙烯和异佛尔酮二异氰酸酯(IPDI)为原料,合成了异氰酸根封端的聚脲预聚体,再用硅烷偶联剂KH550对预聚体进行封端,制备了硅烷封端聚脲。用红外光谱、热重分析、差示扫描量热分析、拉伸强度、吸水率、静态水接触角等手段对材料的结构和性能进行了表征,并讨论了NCO与胺基的摩尔比(R值)对材料性能的影响。结果表明,经过封端改性后,聚脲的力学性能、热稳定性、耐寒性和耐水性得到明显提高,R值为1.05时拉伸强度达4.14MPa,断裂伸长率为420%,在去离子水中放置96h吸水率仅为2.72%,静态水接触角达到78.2°。  相似文献   

3.
上海市合成树脂研究所以多官司能度、水溶性聚醚多元醇和异佛尔酮二异氰酸酯(IPDI)进行预聚反应合成-NCO封端的聚氨酯(PU)预聚体,再和甲基丙烯酸羟乙酯(HEMA)反应合成含有双键的聚氨酯丙烯酸酯(PUA)预聚体。该预聚体流动性好,易乳化于水,  相似文献   

4.
以聚四氢呋喃醚二醇(PTMG)、4,4′-二苯基甲烷二异氰酸酯(MDI)和1,4-丁二醇(BDO)为原料,通过预聚体法制得不同异氰酸酯(—NCO)基含量预聚体,用BDO作扩链剂合成浇注型聚氨酯(PU)弹性体。考察了预聚体中—NCO基含量对PU弹性体力学性能的影响,用X射线衍射仪、维卡软化点测定仪和热失重分析仪对材料进行分析表征。结果表明:PU弹性体随预聚体—NCO基含量的增加,硬度、拉伸强度、模量和撕裂强度增大,断裂伸长率和冲击弹性下降。当预聚体—NCO基含量为8.0%时,PU弹性体的综合力学性能最佳,拉伸强度和撕裂强度分别是39.4MPa和142.7kN/m;维卡软化温度达到127.5℃,具有较好的热性能。  相似文献   

5.
聚氨酯预聚体黏度的影响因素探究   总被引:1,自引:0,他引:1  
聚氨酯预聚体的黏度直接影响聚氨酯弹性体的施工性能,进而影响涂层的施工质量和性能。以4,4’-二苯基甲烷二异氰酸酯(MDI)和聚醚多元醇PTMG1000为原料,在80℃下反应2 h制备了不同异氰酸酯基含量的预聚体,研究了异氰酸酯基含量、温度和制备方法对预聚体黏度的影响规律。结果表明:预聚体的黏度主要与温度和异氰酸酯基含量有关,制备方法对黏度影响较小;预聚体的黏度随温度的升高呈指数降低,异氰酸酯基含量越高黏度越低;制备低异氰酸酯含量的预聚体后,再加入MDI调节异氰酸酯含量的方式和直接制备相同含量的异氰酸酯含量的预聚体在黏度上变化不大。  相似文献   

6.
蓖麻油基聚氨酯的制备及其性能研究   总被引:3,自引:1,他引:2  
采用可再生的蓖麻油、甘油、TDI为原料,合成出端-NCO的蓖麻油基聚氨酯(PU)预聚体.对预聚体中NCO的含量进行了测定,并采用FT-IR对材料进行了定性分析;采用TG对蓖麻油基PU膜的热性能进行分析,并对固化后的材料力学性能进行了测试.结果表明:蓖麻油基PU预聚体的NCO含量在5.25%~4.93%时,体系在-18~40 ℃能固化成膜,且成膜物具有较好热学性能和力学性能.  相似文献   

7.
以聚丙二醇(PPG2000)和二苯基甲烷二异氰酸酯(MDI)为原料合成了异氰酸根封端的聚氨酯预聚体(PUP),分别以合成的预聚体和市售的聚氨酯预聚体为增韧剂改性酚醛泡沫,研究了PUP用量及异氰酸根含量对酚醛泡沫力学性能、热稳定性能、导热性能及阻燃等性能的影响,并对改性前后的酚醛泡沫进行了电子显微镜扫描泡孔结构和红外光谱分析。结果表明,聚氨酯预聚体用量为5%(wt,质量分数,下同),异氰酸根含量为4.1%时,酚醛泡沫的韧性和保温性能最好,其中相对弯曲强度和相对压缩强度分别为5.11kPa·m~3/kg和3.33kPa·m~3/kg,分别比纯泡沫提高了86.5%和43.5%;改性泡沫导热系数为0.057W/m·K,比纯泡沫导热系数(0.064W/m·K)低;增韧的酚醛泡沫热稳定性能略有降低,但下降幅度不大;此外,聚氨酯增韧后的酚醛泡沫阻燃性能均大于34%,具有优良的阻燃性能,且酚醛泡沫闭孔率高、泡空分布均匀。  相似文献   

8.
酚醛泡沫是近几年发展起来的一类新型泡沫塑料,具有阻燃、低烟、自熄等独特性能,传统酚醛泡沫是由酚醛树脂在固化剂、发泡剂、表面活性剂及其他助剂存在条件下,同时发泡、固化制成。固化后的酚醛树脂因自身结构的缺陷,从而使得制备的酚醛泡沫存在延伸率低、硬度大、耐冲击性差、粉碎率高等问题,限制了其产品应用及快速发展。因此对酚醛树脂及其泡沫进行改性研究以降低其脆性,提高其韧性,具有一定理论和现实意义。文中阐述了酚醛泡沫的增韧方法,着重介绍了直接混合法、NCO链端预聚体法以及OH链端预聚体法等3种聚氨酯预聚体增韧酚醛泡沫的方法,并分析了聚氨酯预聚体增韧酚醛泡沫的增韧机理。最后总结了聚氨酯预聚体改性酚醛泡沫存在的问题。  相似文献   

9.
采用端异氰酸酯预聚体和端羟基聚醚预聚体制备了聚氨酯包覆层,探讨了异氰酸酯指数(R值)对聚氨酯包覆层力学性能、粘接性能及其与双基推进剂的相容性的影响。研究表明:R值对聚氨酯包覆层的性能有较大影响。其中,拉伸强度和粘接强度随R值的增大而逐渐增大,相容性随R值的增大逐渐变差。R值为1.0时,包覆层/推进剂相容性级别为一级;而R值为1.4时,相容性则降为三级,相容性较差。  相似文献   

10.
以咪唑为端异氰酸酯基封闭剂,制备封闭聚氨酯预聚体,然后以羧基丁苯胶水溶液进行反相乳化,并加入氮丙啶,制得系列水分散羧基丁苯胶/封闭聚氨酯植物纤维防水增强剂(XSBRL/BPU)。XSBRL/BPU的综合性能与BPU封闭率、羧基丁苯胶/封闭聚氨酯比例、交联剂氮丙啶含量及复合乳液的添加量有关。当封闭率BR=10%、m(BPU)/m(XSBRL)=2/1、ω(氮丙啶)=2%、ω(乳液)=8%时,纸基复合材料具有良好防水性能、黏合强度和机械性能,其中,耐折度为158次、施胶度为180s、干抗张指数为63.4N.m.g-1、湿抗张指数为33.8N.m2g-1、湿强度为53.3%。  相似文献   

11.
从原料和工艺两方面出发,对以γ-氨丙基三乙氧基硅烷(KH550)为基础的硅烷改性聚氨酯(SPU)进行了改善.原料方面,改性后的KH550由伯氨基转化为仲氨基,反应活性降低;工艺方面,将KH550加料顺序提前.试验结果表明:这两种方法均有利于降低SPU树脂的黏度和提高反应平稳性;较好解决了由于黏度上升太快引起的KH550自聚凝团问题.  相似文献   

12.
万达  岳淑丽 《包装工程》2014,35(1):51-54
目的以聚酯二元醇(PBA)、异佛尔酮二异氰酸酯(IPDI)、植物油多元醇蓖麻油和硅烷偶联剂为原料,制备一种耐蒸煮的无溶剂聚氨酯胶粘剂。方法采用红外光谱(FT-IR)、热重分析(TG)等手段对胶粘剂的结构和性能进行了分析表征,同时考察了不同有机硅烷偶联剂的添加量对胶粘剂固化时间、粘结强度、固化膜吸水率等的影响。结果适量添加硅烷偶联剂可以有效提高胶粘剂的粘结强度、热稳定性和耐蒸煮性,但是硅烷偶联剂添加量过多会导致胶粘剂分层,固化困难。结论硅烷偶联剂添加量在1%~2%为最佳。  相似文献   

13.
Surface modification to develop a biomolecules-presenting surface is of interest, both from a scientific and an industrial point of view. In this research, a penta-block-coupling polymer of warfarin–PEO–MDI–PEO–warfarin was specially designed as the surface modifying additive (SMA). The warfarin-modified polyurethane surfaces were then prepared by dip-coating method. Attenuated total reflection fourier transform infra-red (ATR-FTIR) spectra revealed that the urethane segments in the SMA could penetrate into the hard block of segmented polyurethane (SPU) via intermolecular hydrogen bonds. The X-ray photoelectron spectroscopy (XPS) results indicated that the intermolecular hydrogen bonds were strong enough to form stable warfarin-PEO composite surfaces in an aqueous environment. Fibrinogen and albumin adsorption onto unmodified and SMA-modified SPU was investigated by the 125I-labeled method. The surface for attracting and reversibly binding albumin, which was proved to suppress the platelet adhesion and prolong the clotting time, has been developed by the simple coating of the novel SMA in SPU.  相似文献   

14.
有机硅烷偶联剂对水性聚氨酯材料性能的影响   总被引:2,自引:0,他引:2  
赖小娟  沈一丁  王磊 《功能材料》2011,42(3):490-493
以IPDI为硬段,PTMG1000为软段,TMP为交联剂,APTES为封端剂,合成了一系列硅烷偶联剂改性水性聚氨酯乳液,并制备了水性聚氨酯的固化膜.FT-IR分析表明,APTES上的一NH2 与聚铵酯的端--NCO发生反应,成功地将硅烷结构引入聚氨酯分子中.TG分析表明,APTES的改性,提高了聚氨酯热稳定性.随着w(...  相似文献   

15.
Sulfonated polyurethanes (SPU) were used as corrosion inhibitor for mild steel in acidic solution. The sulfonation of the > N-H groups of the urethane linkages was confirmed from Nuclear Magnetic Resonance (NMR) and Fourier Transform Infra Red (FTIR) spectroscopic techniques. The inhibition efficiency of sulfonated polyurethanes, prepared from two different routes, was investigated using different techniques. The effects of microstructure of polyurethane (PU), degree of sulfonation, time of immersion and temperature on the inhibition of corrosion were discussed. The disc-like nanoparticles, so-called nanoclay, either suspended or chemically attached to SPU chains (nanocomposites) dramatically enhanced the inhibition efficiency for mild steel in acidic medium. All the inhibitors retard the corrosion rate by getting themselves adsorbed on the corroding surface by following the Langmuir adsorption isotherm. The surface analysis of inhibited and uninhibited samples was performed using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Among the various inhibitors used, the nanocomposite of polyurethane was the most effective. Molecular modeling helped in determining the extent of packing of the SPU chains leading to better inhibition efficiency.  相似文献   

16.
2-甲基丙烯酰氧乙基磷酰胆碱(MPC)与甲基丙烯酸异辛酯(EHMA)通过自由基聚合制备共聚物PMEH20,并将PMEH20添加到基材聚氨酯中制备了共混膜。牛血清蛋白(BSA)吸附性测试显示当PMEH20质量分数为15%时,BSA吸附量比空白聚氨酯下降了81.7%;血小板粘附性能测试显示,含有PMEH20的聚氨酯共混膜粘附了更少的血小板;动态水接触角测试发现共混膜中磷酰胆碱基团可以通过翻转重排于薄膜表面;薄膜力学性能测试显示,在PMEH20质量分数达到10%时,膜材料的综合力学性能最好。  相似文献   

17.
Segmented polyurethane(SPU)s are block polymers which have a good elastic property and thermoplasticity. However, the biocompatibility of SPU is not sufficient, and a living organism rejects the SPU as a foreign material. Thus, some modification is needed to provide excellent biocompatibility and retain the good physical characteristics of the SPUs. In this study, we blended the 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer with SPU to prepare an SPU/MPC polymer alloy. We investigated the effects of the molecular weight (Mw) of the MPC polymer on the microdomain structure and mechanical property of the polymer alloy. When the MPC polymer with a higher Mw was blended with SPU, the polymer alloy underwent a reduction in mechanical strength. On the other hand, even when the lower Mw of the MPC polymer was blended with SPU, differential scanning calorimetric analysis revealed that the MPC polymer chains did not disrupt the crystallinity of the hard segments of SPU and the polymer alloy could maintain its physical properties the same as that of the original SPU. We investigated the adsorption of immunoglobulin (IgG) on the surface of the polymer alloy for evaluation of its fundamental biocompatibility. The SPU/MPC polymer alloy lowered the amount of adsorbed IgG compared to that on SPU. This means that the blending of the MPC polymer significantly improved the biocompatibility of the SPU. We succeeded in preparing an SPU/MPC polymer alloy that possesses both the good mechanical property of SPU and the improved biocompatibility using MPC polymers.  相似文献   

18.
Segmented polyurethane(SPU)s are block polymers which have a good elastic property and thermoplasticity. However, the biocompatibility of SPU is not sufficient, and a living organism rejects the SPU as a foreign material. Thus, some modification is needed to provide excellent biocompatibility and retain the good physical characteristics of the SPUs. In this study, we blended the 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer with SPU to prepare an SPU/MPC polymer alloy. We investigated the effects of the molecular weight (Mw) of the MPC polymer on the microdomain structure and mechanical property of the polymer alloy. When the MPC polymer with a higher Mw was blended with SPU, the polymer alloy underwent a reduction in mechanical strength. On the other hand, even when the lower Mw of the MPC polymer was blended with SPU, differential scanning calorimetric analysis revealed that the MPC polymer chains did not disrupt the crystallinity of the hard segments of SPU and the polymer alloy could maintain its physical properties the same as that of the original SPU. We investigated the adsorption of immunoglobulin (IgG) on the surface of the polymer alloy for evaluation of its fundamental biocompatibility. The SPU/MPC polymer alloy lowered the amount of adsorbed IgG compared to that on SPU. This means that the blending of the MPC polymer significantly improved the biocompatibility of the SPU. We succeeded in preparing an SPU/MPC polymer alloy that possesses both the good mechanical property of SPU and the improved biocompatibility using MPC polymers.  相似文献   

19.
为了改进纳米氧化锆(ZrO_2)在涂料中的分散性,以丙酮为介质,用3-氨基丙基三甲氧基硅烷(APS)对纳米ZrO_2进行了改性,并在镀锡板表面制备了改性纳米ZrO_2/水性聚氨酯(WPU)复合涂层。通过扫描电镜、原子力显微镜、红外光谱、电化学测试、盐雾腐蚀、附着力测试等技术,研究了WPU与不同含量改性纳米ZrO_2复合涂层的防腐蚀性能。结果表明:改性纳米ZrO_2的含量为0.2%(质量分数)时,在WPU中的团聚现象消失,分散性良好,该复合涂层具有优良的耐蚀性和较大的附着力。  相似文献   

20.
使用γ-氨丙基三乙氧基硅烷(KH550)作为偶联剂,对铜粉(Cu)进行了表面化学改性;研究了采用不同偶联剂浓度改性Cu粉时对50% Cu/聚氨酯(PU)复合涂层力学性能、红外发射率、耐腐蚀性能的影响,并对其影响机制进行了分析。结果表明:经过改性后,硅烷偶联剂接枝于Cu粉表面。与未改性样品比较,适当硅烷偶联剂浓度改性的50% Cu/PU涂层在8~14μm波段的红外发射率仍然保持很低(0.1);涂层力学性能有较大的提高,附着力从2级增加到1级,铅笔硬度由4H增加到6H,两者均达到最高级;在保持涂层红外发射率不变的前提下,涂层耐碱、酸、盐时间分别从1、50、10h改善到90、60、50h;分析认为Cu粉的改性改善了其与聚氨酯界面的相容性及涂层致密性。  相似文献   

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