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1.
以聚己二酸乙二醇酯二元醇、甲苯二异氰酸酯、乙二胺基己磺酸钠(N60)等为主要原料,制备了一系列不同N60用量的磺酸盐型水性聚氨酯(WPU)乳液。研究了N60用量对WPU乳液及其胶膜性能的影响,并通过FT-IR、TEM、TGA等方法进行表征。结果表明,磺酸盐型WPU乳液的贮存、冻融、高温稳定性均较好。随N60用量的增加,磺酸盐型WPU乳液粒径先减小后增大,粒径分布变窄,胶膜的拉伸强度、吸水率呈上升趋势、断裂伸长率下降。TEM图显示微粒分散性好,呈球形;相对于羧酸型WPU,磺酸盐型WPU胶膜的拉伸强度提高,热稳定性更好。  相似文献   

2.
采用丙酮法制备了复合薄膜用的水性聚氨酯(WPU)乳液胶粘剂,研究了催化剂用量对WPU反应速率及其性能的影响。研究结果表明,适量的催化剂能明显加快聚氨酯(PU)预聚体的反应速率;当催化剂质量分数为0.1%时,WPU乳液的粘度和复合薄膜的T型剥离强度最大,但WPU胶膜的玻璃化转变温度(Tg)降低,由未加催化剂时的-25.5℃降低到-29.1℃。  相似文献   

3.
以端羟基聚丁二烯(HTPB)、聚醚二元醇(N-220)、异佛尔酮二异氰酸酯(IPDI)为主要原料,制备了改性水性聚氨酯(WPU)。研究了端羟基聚丁二烯(HTPB)的含量对聚氨酯乳液粒径、贮存稳定性,以及对涂膜耐水性、力学性能、低温柔韧性的影响。结果表明:在预聚反应中,固定总n(—NCO)∶n(—OH)为1.3,w(DMPA)为6%,HTPB添加量在40%(占聚醚N-220的量)以下时,粒径变化不大,乳液稳定性较好;针对不同HTPB添加量,控制好亲水基团的含量,可以获得分散性良好、贮存稳定的聚氨酯乳液;随着HTPB添加量逐渐增大,涂膜的拉伸强度逐渐增大后变小,断裂伸长率和吸水率逐渐减小后变大,低温柔韧性变好。当HTPB添加量在30%左右,涂膜的综合性能最佳。  相似文献   

4.
In recent years, structural colors derived from photonic crystals (PCs) with a periodically ordered nanostructure are gorgeous and iridescent, but once their structure is destroyed, they will fade. In this work, the feasibility of the application of bio-based waterborne polyurethanes (WPU) in structural color films was explored. The structural stability of PCs is enhanced bio-based WPU as a kind of green product, which can replace solvent polyurethane one. A tung oil polyol (TOP) is fabricated by one-step method with simple purification process and used to prepare waterborne polyurethane dispersions (WPUD). More introduction of TOP into the WPUD may help improve tensile strength and hydrophobic capability. It shows excellent mechanical properties with 16.8 MPa in tensile strength and water contact angle 109.5°. The SEM images confirmed that bio-based WPU is more conducive to the self-assembly of silica particles than traditional WPU.  相似文献   

5.
环氧改性水性聚氨酯涂料的合成与性能研究   总被引:34,自引:5,他引:34  
采用环氧树脂与聚醚、二羟甲基丙酸(DMPA)和甲苯二异氰酸酯(TDI)反应制备水性聚氨酯涂料。研究发现随着所用的环氧树脂的环氧值的降低,改性水性聚氨酯涂膜的硬度和拉伸强度逐渐提高,断裂伸长率则随着降低。选用环氧值为0.44的环氧树脂所合成的改性水性聚氨酯的涂膜硬度达到玻璃硬度0.70;随着环氧树脂添加量增大,涂膜机械性能增加。采用后添加环氧树脂的合成工艺,可制备贮存稳定的水性聚氨酯乳液;凝胶渗透色谱(GPC)分析表明环氧树脂改性水性聚氨酯提高了聚氨酯的分子量。性能测试表明环氧改性水性聚氨酯涂料具有涂膜硬度高、耐水性好和耐溶剂性好等优点。  相似文献   

6.
以异佛尔酮二异氰酸酯(IPDI)和异佛尔酮二胺(IPDA)为硬段,分别以聚四氢呋喃二醇(PTMEG2000)、聚己二酸新戊二醇酯二醇(PNA2000)及其混合物为软段,制备了系列水性聚氨酯(WPU)乳液。通过ATR-FTIR对聚氨酯结构进行了表征分析,采用拉伸测试、热失重分析、动态力学分析及耐水性测试等手段对WPU胶膜性能进行了研究,探讨了不同软段结构对WPU胶膜性能的影响。结果表明:聚酯聚醚混合型水性聚氨酯的力学性能优于单一软段水性聚氨酯,其中PTMEG与PNA质量比为2∶1时力学性能最好;PTMEG型WPU胶膜的初始分解温度高于PNA型WPU胶膜,失重50%时分解温度相反;PTMEG型WPU胶膜的耐水性好于PNA型WPU胶膜。  相似文献   

7.
合成革用水性聚氨酯的制备   总被引:2,自引:0,他引:2  
以异佛尔酮二异氰酸酯( IPDI),聚酯或聚醚多元醇、二羟甲基丙酸(DMPA)为主要原料,采用预聚体法合成了脂肪族革用水性聚氨酯(WPU),用三甲氧基三聚氰胺树脂(TMMM)对WPU进行交联反应成膜,考察了nNCO/nOH,DMPA用量、聚酯或聚醚种类以及TMMM对WPU性能的影响.结果表明,随着nNCO/nOH的增加...  相似文献   

8.
Although tremendous efforts have been dedicated to developing environmentally friendly bio-based waterborne polyurethane (WPU) dispersions from vegetable oil, the fabrication of WPU dispersions solely derived from vegetable oil-based polyol with excellent comprehensive properties is still challenging. In the present work, novel bio-based WPU dispersions derived from castor oil and soy polyol is successfully modified by phosphorus-nitrogen chain extender [bis(2-hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester (BH). The structure and properties of the dispersions and films are characterized systematically by Fourier transform infrared spectroscopy, thermogravimetric analysis , mechanical test, and limiting oxygen index (LOI), etc. The results indicate that bio-based WPU films display moderate mechanical performance by adjusting BH content, and the WPU film containing 100% BH with 47.8% biobased content has a tensile strength of 8 MPa and the highest Young's modulus of 62.3 MPa. The incorporation of BH can increase the production of char residue. The flame retardancy of WPU films increase gradually with the BH molar content, and the LOI value of the WPU100 with 1.53 wt% phosphorus content can reach as high as 28.1%. This work may provide a new approach to develop high biobased content, eco-friendly, flame retardant WPU for application in the surface coating industry.  相似文献   

9.
Biodegradable films of poly(propylene carbonate)/poly(vinyl alcohol)-thermoplastic polyurethane [PPC/(PVA-TPU)] ternary blends were successfully prepared by melting blending method. The mechanical properties of poly(propylene carbonate) blown film were greatly improved by blending PPC with PVA-TPU. In order to afford the melt processing of PVA, the PVA-TPU binary blend was firstly prepared using thermoplastic polyurethane as a polymeric plasticizer. The rheological behavior, mechanical properties and morphology of these blends were studied. Considering its melt viscosity and thermally processing temperature, the PVA-50%TPU, as a modifier, was blended with PPC to prepare PPC/(PVA-TPU) ternary blend. SEM observation revealed a basic one-phase morphological structure with very good interfacial adhesion between the extremely blurred PPC and PVA-TPU two components. Meanwhile, the miscibility of the ternary components was verified by only one glass-transition temperature obtained from DMA tests. The tensile strength and tear strength of PPC/(PVA-TPU) blown films were determined at different temperatures. The results demonstrate that the mechanical properties of PPC/(PVA-TPU) films were enhanced dramatically at low temperature when compared with neat PPC. At room temperature, PPC/30 %(PVA-50%TPU) blown film exhibited a tensile strength of 26 MPa, and an elongation at break of 484.0 %. Its tear strength in the take-up direction is 124.1 kN/m, and the one in machine direction is 141.9 kN/m. At a low temperature of 0 °C, PPC/30 %(PVA-50%TPU) exhibited a tensile strength of 40.7 MPa and tear strength of 107 kN/m, which are 153 % and 142 % of those of neat PPC respectively. The blending of PPC with the PVA plasticized with TPU provides a practical way to extend the application of the new biodegradable polymer of PPC in the area of blown films.  相似文献   

10.
苯酐聚酯多元醇合成水性聚氨酯的研究   总被引:1,自引:0,他引:1  
以苯酐聚酯二元醇(APP)为主要原料合成了水性聚氨酯(WPU)树脂,探讨了n(-NCO)/n(-OH)比值及扩链剂等对WPU成膜性能的影响。研究结果表明,适度交联可提高WPU胶膜的拉伸强度和耐水性;当w(二羟甲基丙酸)=3.3%、n(-NCO)/n(-OH)=4.0和w(乙二胺)=1.0%时,WPU胶膜的综合性能最好;与其他多元醇[如聚四氢呋喃多元醇(PTMEG)、聚醚多元醇(N-220)和聚酯多元醇(PS)等]合成的WPU树脂相比,用APP合成的WPU树脂,其成膜光泽和断裂伸长率较好、综合性能最优。  相似文献   

11.
A waterborne polyurethane (WPU) prepolymer was synthesized with poly(tetramethylene glycol) to form the soft segment, dimethylolpropionic acid as a hydrophilic chain extender, and isophorone diisocyanate. Moreover, the graft and block copolymer emulsification of WPU–polysiloxane and their films was carried out through reactions between the WPU prepolymer, aminoethyl aminopropyl dimethicone (AEAPS), and a linear polyether-blocked amino silicone (LEPS), respectively. The properties of the structure and formed films of the WPU were characterized with Fourier transform infrared spectrometry, gel permeation chromatography, X-ray diffraction, thermogravimetric analysis, dynamic thermomechanical analysis, and X-ray photoelectron spectroscopy; the measurement of the water contact angle; the testing of the water absorption; and so on. The WPU–polysiloxane emulsion showed a high stability, and the molecular weight of WPU increased. Moreover, the glass-transition temperature (Tg) of the soft segment of polysiloxane that was incorporated into the WPU shifted to a lower temperature range, whereas the Tg of the hard segment shifted to a higher temperature range, and the crystallinity of the WPU–polysiloxane film was reduced. There was a greater degree of crosslinking and accumulation of polysiloxane segments on the surface of the WPU emulsion that was modified with AEAPS in comparison to the LEPS-modified WPU emulsion. Therefore, the water resistance of the AEAPS-modified WPU was higher than that of the LEPS-modified WPU. The rigidity and elasticity of the WPU–polysiloxane film improved, whereas its tensile strength did not change much after AEAPS was used. However, this was not true after LEPS was used, as the tensile strength decreased significantly. Nevertheless, the flexibility and plasticity of the WPU–polysiloxane film were enhanced after LEPS was used. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47226.  相似文献   

12.
颜财彬  傅和青  陈焕钦 《化工学报》2012,63(7):2258-2265
采用预聚体分散法制备了一系列固含量为50%的水性聚氨酯(WPU),并通过傅里叶红外光谱(FT-IR)、粒径分析仪、X射线衍射(XRD)、差示扫描量热分析(DSC)、拉力试验机等仪器进行表征,研究了HDI/IPDI摩尔比对WPU的乳液性能和胶膜结晶性能、力学性能、耐水性能,以及基材EVA/PVC粘接性能的影响,分析了不同摩尔比的HDI/IPDI和粘接时间与WPU胶黏剂对EVA/PVC粘接性能的关系。研究发现,随着HDI/IPDI摩尔比增加,水性聚氨酯的乳液性能、软硬段的结晶性都得到提高,而胶膜拉伸强度呈先增大后减小的趋势,断裂伸长率则先减小后增大。所有WPU胶膜都有很好耐水性,胶膜吸水率都在5.0%(质量)以下。粘接实验结果表明,WPU胶黏剂对EVA/PVC具有优异的粘接性能,24 h后可对基材产生界面破坏,随着HDI/IPDI摩尔比增加,胶黏剂的粘接强度增大。当HDI/IPDI=7∶1时,水性聚氨酯的综合性能最好。  相似文献   

13.
以聚己二酸丁二醇酯二醇(PBA3000)、异佛尔酮二异氰酸酯(IPDI)和2,2-二羟甲基丙酸(DMPA)为主要原料,合成了羧酸型水性聚氨酯(WPU)。结果表明:一步法和两步法制成的WPU分散液及其胶膜特性相近,但一步法制备工艺更加简单;随着DMPA含量不断增加,预聚过程中体系黏度和分散液电导率上升,WPU胶膜的拉伸强度、硬度和吸水率增大,断裂伸长率和分散液粒径(100 nm)减小;当n(PBA)∶n(DMPA)=2∶3时,R值越大,预聚过程中体系黏度越低,WPU胶膜的拉伸强度和硬度越大,而断裂伸长率和吸水率越小;当w(-COOH)=1.09%~2.37%时,WPU分散液的稳定性较好。  相似文献   

14.
A novel waterborne polyurethane (WPU) coating with a self-roughed surface is prepared using a general prepolymer emulsion polymerization method. A rough surface is formed by crosslinking the WPU particles through the introduction of a polyfunctional amine-based chain extender. Ethylenediamine, diethylenetriamine (DETA) and triethylenetetramine (TETA) with different functional groups are used as chain extenders, and their effect on the surface morphology and gloss of WPU films is investigated. DETA and TETA form a rough surface on the WPU film by crosslinking the polymer chains and promoting phase separation between soft and hard segments. A rough surface reflects light diffusely, resulting in a decrease in the gloss of the film. Overall, the chain extension improves the thermal stability and tensile strength of the WPU film. In particular, the WPU film with DETA, exhibiting the highest chain extension effect, shows the lowest gloss value, the highest tensile strength and thermal stability. The present series of WPU materials, prepared without matting agents and special treatment processes, can be an effective alternative for producing low-gloss coatings. © 2022 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry.  相似文献   

15.
采用丙酮法制备水性聚氨酯树脂,再复配聚醋酸乙烯酯乳液和松香乳液,提高了水性聚氨酯树脂粘合剂与0PP膜的粘合性。研究了粘合剂组成、烘干时间对0PP膜粘合性的影响,最后进行了优化正交实验。优化结果表明,当聚氨酯与聚醋酸乙烯酯乳液、松香乳液的配比(质量比)为11:9:3,干燥温度60℃,干燥时间为60s时,聚氨酯复合胶粘剂的力学性能较好,其抗拉强度为12.1N·mm^-2以。  相似文献   

16.
A eugenol-based silicone-containing monomer 4,4′-(1,1,3,3-tetramethyldisiloxane-1,3-dipropyl)bis-2-methoxyphenol(EUSi) was synthesized from eugenol and 1,1,3,3-tetramethyldisiloxane via the hydrosilylation reaction. And waterborne polyurethane (WPU) with excellent properties was obtained by using EUSi as a type of diol chain extender. The unique combination of rigidity and flexibility in the chemical structure of EUSi greatly facilitated the mechanical properties, thermal properties, and water resistance of WPU. With only a 3% dosage of EUSi, the maximum tensile strength was increased from 6.2 to 22.4 MPa, while the water absorption was decreased from 31.3% to a surprisingly 7.6%. Our work provides a new convenient strategy for the preparation of organosilicon-modified WPU with improved performance.  相似文献   

17.
以聚己内酯二醇(PCL)、聚丙二醇(PPG)、六亚甲基二异氰酸酯(HDI)、异佛尔酮二异氰酸酯(IPDI)、环氧树脂E51、二羟甲基丙酸(DMPA)、1,6-己二醇(HDO)和50%乙二胺基乙磺酸钠水溶液(A-95)为主要原料,合成了一系列环氧树脂改性的水性聚氨酯(WPU)乳液。采用FT-IR、DSC及力学性能等测试手段,研究了环氧树脂E51的加入对WPU性能的影响。结果表明:环氧树脂成功引入到水性聚氨酯的分子链上;环氧树脂E51改性WPU乳液的固含量可达到41%~54%;E51质量分数为6%时,乳液贮存稳定性最好,胶膜拉伸强度达到8.55 MPa,断裂伸长率为734%;环氧树脂E51的引入使胶膜拉伸强度增大,耐水性得到明显提高。  相似文献   

18.
以异氟尔酮二异氰酸酯(IPDI)、聚四氢呋喃醚二醇(PTMG)以及二羟基甲基丙酸(DMPA)为主要原料合成水性聚氨酯(WPU)预聚体,在此基础上加入环氧树脂(EP,E-44)制备了环氧树脂改性水性聚氨酯(PUE)复合乳液。探讨了不同环氧树脂含量对复合乳液性能的影响,并对胶膜的力学性能、吸水率、接触角和热性能等进行了表征。结果表明,适量的环氧树脂改性过后的复合乳液比较稳定;随着环氧树脂含量的增加,乳液粒径和黏度增大,同时胶膜的拉伸强度增大,水的接触角增大,胶膜的热稳定性增加。E-44质量分数为7%~9%时,复合乳液及其胶膜的综合性能较好。  相似文献   

19.
A novel graphene nanomaterial functionalized by octa(aminopropyl) polyhedral oligomeric silsesquioxane (OapPOSS) was synthesized and then confirmed by Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), Raman spectroscopy, X‐ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy with energy‐dispersive X‐ray spectroscopy (SEM EDX), atomic force microscopy, and X‐ray diffraction. The obtained functionalized graphene (OapPOSS‐GO) was used to reinforce waterborne polyurethane (WPU) to obtain OapPOSS‐GO/WPU nanocomposites by in situ polymerization. The thermal, mechanical, and hydrophobic properties of nanocomposites as well as the dispersion behavior of OapPOSS‐GO in the polymer were investigated by TGA, a tensile testing machine, water contact angle tests, and field emission SEM, respectively. Compared with GO/WPU and OapPOSS/WPU composites, the strong interfacial interaction between OapPOSS‐GO and the WPU matrix facilitates a much better dispersion and load transfer from the WPU matrix to the OapPOSS‐GO. It was found that the tensile strength of the OapPOSS‐GO/WPU composite film with 0.20 wt % OapPOSS‐GO exhibited a 2.5‐fold increase in tensile strength, compared with neat WPU. Better thermal stability and hydrophobicity of nanocomposites were also achieved by the addition of OapPOSS‐GO. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44440.  相似文献   

20.
Waterborne polyurethane (WPU) was prepared from toluene diisocyanate, polypropylene glycol, 2,2‐bis(hydroxymethyl)propionic acid and a diol containing triethoxysilane group as the chain extender which was synthesized via Michael addition between 3‐triethoxysilylpropylamine and 2‐hydroxyethylacrylate. Different amounts of nanosilica were incorporated into the WPU to prepare WPU/nanosilica composites. The results showed that the particle size of the emulsions increased and their viscosity decreased first and then increased with increasing the amount of nanosilica. Incorporation of nanosilica into WPU enhanced the water contact angle and thermal stability of the composites films, meanwhile, their tensile strength and hardness increased first and then decreased. However, increasing the amount of nanosilica resulted in reduction in the elongation at break of the films. It suggested that nanosilca was anchored into the side chain of WPU due to the condensation process between the triethoxysilane group in the side chain of WPU molecular and the silanols group on the surface of nanosilica. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40526.  相似文献   

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