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以端羟基聚丁二烯(HTPB),甲苯二异氰酸酯(TDI)以及有关配合剂为原料,制备了聚烯烃聚氨酯胶粘剂,研究了蓖麻油,三羟甲基丙烷,丙三醇对胶粘性能的影响。测试了胶粘剂的本体强度,粘接强度以及工艺性能。结果表明,以蓖麻油作为胶粘剂的增强剂,与HTPB的羟基(-OH)含量摩尔比为0.25,可以获得力学性能,粘接性能和工艺性能都比较优越的聚烯烃聚氨酯胶粘剂。 相似文献
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提高EPDM绝热层生熟界面粘接性能研究 总被引:2,自引:0,他引:2
以碳纳米管(CNTs)、硅烷偶联剂(WD)、N-溴代琥珀酰亚胺(NBS)、N-氯代琥珀酰亚胺(NCS)、甲基丙烯酸缩水甘油酯(GMA)和粘接促进剂(ZC)等分别作为改性剂,在未硫化EPDM(三元乙丙)绝热层(Eu)与已硫化EPDM绝热层(Ev)之间的界面粘接用胶粘剂基础配方中,通过加入不同改性剂来优选改善Eu/Ev界面粘接性能的适宜改性剂及用量。结果表明:采用ZC作为Eu/Ev界面粘接用胶粘剂基础配方的改性剂,可稳定提高Eu/Ev界面的粘接性能;将ZC改性胶粘剂用于Eu/Ev界面的粘接时,其粘接强度超过3.5 MPa,并且其储存稳定性和耐热老化性能均较好。 相似文献
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用聚氨酯改性的丙烯酸材料是近年来开发应用的一种新型材料,这种改性材料在涂料、油墨和胶粘剂等领域广泛应用。丙烯酸乳液具有和高弹性聚合物掺和性能好的特点。聚氨酯属高弹性聚合物类,它添加到丙烯酸乳液中去,能改进丙烯酸乳液的粘接、柔韧和延伸性能,且不使丙烯酸胶粘剂本身的特点受到影响。聚氨酯水分散体改性的丙烯酸树脂胶粘剂既能提高其粘接强度,又具有色 相似文献
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制备了室温快速固化综合性能较好的聚氨酯改性环氧树脂结构胶粘剂,探讨了增韧剂、固化剂等因素对胶粘剂力学性能的影响,通过扫描电镜分析了胶粘剂断裂面的形貌特征,研究了胶粘剂形貌特征与力学性能的关系。结果表明:聚氨酯增韧环氧树脂既有物理交联产生“强迫互溶”和“协同效应”,又与环氧树脂发生了化学反应,产生的化学键进一步加强了聚合物交联密度和聚合物的强度,当PU预聚体用量为环氧树脂的40%时,聚氨酯与环氧树脂形成的互穿网络聚合物互穿程度最大,制备的胶粘剂力学性能最优,室温剪切强度达到20.16MPa。 相似文献
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聚氨酯胶粘剂讲座(连载一) 总被引:2,自引:0,他引:2
一、引言聚氨酯(PU)胶粘剂(包括密封胶)是指分子链中含有氨基甲酸酯键((?)R NH-COR(?))和/或异氰酸酯基团(-NCO)类的胶粘剂。聚氨酯胶粘剂在制备或粘接过程中一般都发生多异氰酸酯化合物或含端基NCO聚氨酯预聚体与活性氢化合物(如含羟基、胺基的化合物、水等)的反应。聚氨酯胶粘剂具有许多优越的物化性能: 相似文献
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采用3-巯丙基三甲氧基硅烷制备了硅烷改性单组分湿固化聚氨酯胶粘剂(SPU)。采用红外光谱、核磁共振氢谱、凝胶渗透色谱和扫描电子显微镜分析了SPU胶粘剂的结构,使用万能电子试验机、邵氏A硬度计测定了硅烷含量对SPU胶粘剂的力学性能、粘接性能与硬度的影响。研究结果表明:3-巯丙基三甲氧基硅烷成功反应到聚氨酯分子链上,减少了体系中异氰酸根(—NCO)的含量;随着硅烷用量的增加,SPU胶粘剂的拉伸强度与拉伸剪切性能升高,硬度降低,表干时间延长;当硅烷用量为理论用量的110%时,SPU胶粘剂的拉伸强度和拉伸剪切强度分别达0.58、0.72 MPa,比纯PU胶粘剂分别提高了7.41%、63.64%;SPU胶粘剂固化时产生的气泡显著减少,外观明显改善。 相似文献
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聚氨酯胶粘剂讲座(连载二) 总被引:1,自引:1,他引:0
第2章聚氨酯化学及粘接机理 2.1 异氰酸酯化学聚氨酯胶粘剂制备及固化过程中,发生的主要反应是异氰酸酯与活性氢化合物的反应,异氰酸酯化学是PU胶粘剂反应机理的重要部分。对于异氰酸酯(聚氨酯)化学,本刊已在聚氨酯泡沫塑料、弹性体、涂料系列讲座中作了较为详尽的阐述,现仅就PU胶 相似文献
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N. Sombatsompop 《应用聚合物科学杂志》1999,74(5):1129-1139
The dynamic mechanical properties of rubber vulcanisates filled with cryogenically pulverized polyurethane foam particles, used as a reinforcing filler, were investigated with respect to storage modulus (E′), loss modulus, and the variation of glass transition temperature. Two rubbers were using styrene–butadiene rubber (SBR) and ethylene–propylene copolymer (EPDM). The effects of filler concentration and filler characteristics (such as particle size and moisture content) were also monitored. It was found that the optimum dynamic mechanical properties of the compounds were obtained when introducing the PU particles of 40–50 parts per hundred (pph) rubber in the SBR and 30 pph in the EPDM, the properties being affected by the size of PU particles and moisture content. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1129–1139, 1999 相似文献
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Phenolic resin (PF) was incorporated into rubbers by in situ polymerization at the vulcanization conditions of rubbers. The PF with a localized three‐dimensional network structure was formed in chloroprene rubber (CR), whereas the fabric PF was formed in ethylene–propylene rubber (EPDM). The study results showed that the PF phase was effective on reinforcing these rubbers. Depending on the morphologies of the formed PF phases, various rubber properties could be significantly enhanced. In the case of CR rubber, the tensile strength, tear strength, and modulus could be considerably enhanced, but the elongation and resilience properties were limitedly affected by PF addition. For EPDM rubber, all mechanical properties were improved, particularly the elongation, about 26% increase. The substantial improvements of mechanical properties of CR and EPDM rubbers were attributed to their morphology, high flexibility, moderate stiffness, and excellent bonding with rubber matrix. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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Samir N. Lawandy Magdy A. H. Zahran Marwa Rabee 《Journal of Adhesion Science and Technology》2018,32(3):302-316
Three types of bio-alkyd resins varies in their oil content and viscosity were added to EPDM rubber mix loaded by three bonding system consisting of Hexamethylenetetramine, Resorcinol and Hydrated silica (HRH). The mixes were charged by certain amount of thermal carbon black. Rubber dough was spread on polyester sheet fabric. The peel strength was used to measure the adhesion strength. The rubber-proofed fabric subjected to UV irradiation at different period of times. The dielectric constant, volume resistivity, thermal stability, water and air permeability of the various rubber coated fabric were examined. The addition of the bio-alkyd resin improved the various mechanical and physical properties of the rubber coated fabric materials. The suggested mechanism of bio-alkyd resin between EPDM and polyester fabric was also studied. 相似文献
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Shujun Zhao Zhong Wang Huiwen Pang Zhi Li Wei Zhang Shifeng Zhang Jianzhang Li Li Li 《大分子材料与工程》2020,305(2)
Plant protein, as a sustainable alternative to petroleum‐derived resin, has exhibited notable potential for engineering wood products without formaldehyde emission, while the poor mechanical and water‐resistant performances limit its practical applications. Inspired by mussel chemistry and structure, a dopamine‐functionalized polyurethane (D‐PU) elastomer is synthesized in this work acting as a bio‐inspired crosslinking unit to improve the properties of soy protein (SP) resin. It is found that the catechol groups of the incorporated D‐PU not only triggers polyurethane to interact with SP matrix giving rise to a stable crosslinking network with excellent load‐bearing capacity, but also serves as a water‐resistant barrier to reduce the water erosion effect on resin. Moreover, a desired microphase‐separated morphology is observed within the continuous protein phase after introducing D‐PU. The microphase‐separated structure simultaneously strengthens and toughens SP adhesive layer, thus achieving high‐efficiency stress transfer and energy dissipation as well as accelerating SP to further permeate into the substrate forming more mechanical adhesion nails. As a result, the modified SP‐D‐PU resin presents an impressive improvement in dry and wet adhesion strength up to 70.5% and 133.9% compared to the pristine SP resin, respectively. The proposed biomimetic design may offer a workable strategy for preparing of high‐performance bio‐based composites. 相似文献
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T. G. Maci -Agull J. C. Fern ndez-Garcí a A. Torr palau A. C. Orgil s Barcel J. M. Martí n-Martí nez 《The Journal of Adhesion》1995,50(4):265-277
Two hydrophilic and two hydrophobic fumed silicas of different characteristics were added to solvent-based polyurethane adhesives (PU). IR spectroscopy, contact angle measurements and rheology (viscosity measurements, determination of viscoelastic properties) were used to monitor the variation of properties of PU adhesives produced by addition of silica. Immediate (green) adhesion was determined by T-peel testing of halogenated synthetic rubber/PU adhesive/halogenated synthetic rubber joints. Silica addition produced a noticeable increase in the PU adhesive viscosity which can be related to the variation of viscoelastic properties. Viscosity of PU adhesives containing hydrophilic silica slightly increased with time after preparation; the increase was less significant in PU adhesives with hydrophilic silica. In the rheological studies, silica imparted shear thinning and negative thixotropy to PU adhesives due to a better dispersion of the silica in the polyurethane during shearing. The addition of silica produces an increase in the storage modulus (G') of PU adhesives, the values obtained being independent of the hydrophilic or hydrophobic nature of the fumed silica. The increase of G' and the changes in tan δ of PU adhesives containing silica corresponded to an improvement in the green adhesion properties of chlorinated rubber/PU adhesive/chlorinated rubber joints. In general, in disagreement with previous results,1 the presence of silica did affect the properties of solvent-based PU adhesives, but these properties were not dependent on the type of silica (hydrophobic or hydrophilic) used in this study. 相似文献
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The effect of ethylene–propylene–diene monomer rubber (EPDM) as an additive on the abrasion resistance of a thermoplastic polyurethane (TPU) resin was investigated. The mechanical properties and microstructure of the resultant TPU/EPDM composites were evaluated, and the surface morphology of the composites after abrasion testing was examined. The results showed that the addition of EPDM greatly improved both the mechanical properties and abrasion resistance of the TPU resin. A TPU/EPDM composite with 8 wt % EPDM demonstrated the highest tensile strength, the largest elongation at break, and the best overall performance. The abrasion of this composite was 27 mg, whereas that of the pure resin was 73 mg. With the further addition of EPDM, the abrasion resistance of the resultant composites decreased, whereas the viscosity increased. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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A. Torr -Palau J. C. Fern ndez-Garcí a A. C. Orgil s-barcel M. M. Pastor-Blas J. M. Martí n-martí nez 《The Journal of Adhesion》1997,61(1):195-211
Fumed silica is a well-known mineral filler of epoxy and polyurethane adhesives. Although effective, the small particle size and the relative high cost of fumed silicas suggest the need for an alternative filler. In this study, the usefulness of adding a natural hydrated magnesium silicate (sepiolite) as a new filler in solvent-based polyurethane (PU) adhesive formulations has been demonstrated. The rheological and adhesion performance of the sepiolite-filled PU adhesive was compared with that in PU adhesives containing fumed silicas. The addition of a filler to PU adhesives provided an increase in viscosity, imparted thixotropy and pseudoplasticity to the adhesive solution, produced an increase in storage and loss moduli, and improved the rheology of the PU. The mechanical properties of adhesive films were increased by adding filler, mainly with fumed silica. On the other hand, the immediate T-peel strength of roughened or (roughened + chlorinated) styrene-butadiene rubber/PU adhesive joints was greatly improved in filled PU adhesives. The effects produced by adding sepiolite or fumed silica to the adhesives were very similar, although in general more noticeable in fumed silica filled PU due to the formation of hydrogen bonds between the filler and the solvent and/or the polyurethane (in sepiolite-filled adhesives, van der Waals forces seemed to be responsible for the interactions between the filler and the solvent and/or polyurethane). 相似文献