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1.
对聚氨酯改性的环氧耐磨涂料的性能进行测定,采用正交试验法分别测定了制备出的耐磨涂料的附着力、硬度、耐磨性,结果发现聚氨酯改性环氧树脂涂料在不同配比情况下具有不同的硬度、附着力和耐磨性。聚氨酯预聚体的使用,提高了环氧树脂的交联度,明显提高了其耐磨性、附着力和硬度;填料碳化硅和固化剂聚酰胺的使用,能够明显改变环氧树脂的耐磨性、硬度和附着力。  相似文献   

2.
聚氨酯改性环氧树脂耐磨涂料的研制   总被引:4,自引:0,他引:4  
以2,4-甲苯二异氰酸酯和蓖麻油为原料,合成了聚氨酯预聚体。使用该聚氨酯预聚体对环氧树脂进行了改性。对各种固化剂进行了筛选。最后研制了一种双组分常温固化耐磨涂料。通过正交实验和单因素实验确定了涂料的最佳配方:聚氨酯5 g,环氧树脂10 g,填料3 g,固化剂2.3 g。由此获得的耐磨性优良的涂膜性能为:表干时间10 h,实干时间不到40 h;耐磨性实验中,磨痕弦长5.4 mm;附着力0级,硬度5 H。  相似文献   

3.
导电油墨的制备与性能研究   总被引:3,自引:0,他引:3  
以2,4-甲苯二异氰酸酯与聚乙二醇反应合成了端异氰酸酯聚氨酯预聚体,并将其用于环氧树脂的改性,通过傅立叶变换红外光谱(FTIP)对聚氨酯预聚体、改性环氧树脂的结构进行了表征.以改性环氧树脂作为连结料,导电炭黑、导电石墨作为导电填料,加上适量的固化剂、溶剂和分散剂,制备了改性环氧树脂基导电油墨.结果表明,聚氨酯预聚体与环氧树脂发生了接枝反应,对环氧树脂E-51成功进行了改性.用改性后的环氧树脂制成的导电油墨与PET薄膜之间有着良好的附着力,印制的导电线路抗弯折性达到了10 000次,可满足柔性印刷电路的要求.  相似文献   

4.
以聚氨酯改性环氧树脂为基体树脂,复配改性三官能团环氧树脂作为补强剂,通过添加耐磨填料、云母粉、耐磨骨料、助剂等,制备了适用于舰船重载甲板的抗碾压耐磨涂料。根据重载履带车辆行驶时涂料所受到的冲击力和剪切力,确定抗碾压耐磨涂层的研制技术路线。通过涂料的弹性模量、屈服强度和抗拉强度等重要力学特征参数,利用有限元软件进行虚拟样机仿真分析,考察重载履带在转弯工况下对涂层施加的压力和剪切力。从补强树脂、耐磨填料及耐磨骨料三方面对涂料配方进行分析和确定,然后对涂层的抗压强度、耐磨性、固化时间、耐冲击性、耐盐水浸泡等性能进行了测试。该抗碾压耐磨涂料耐磨性为24 mg、抗压强度为117 MPa、通过圆铁球冲击和180 d海水浸泡。该涂料具有优异的抗碾压耐磨性能,可用于舰船重载甲板的保护。  相似文献   

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采用聚己二酸乙二醇丙二醇酯(PEPA)和4,4’-二苯基甲烷二异氰酸酯(MDI)为原料合成了聚氨酯预聚体,在预聚体固化剂中掺入环氧树脂,制备了环氧树脂改性MDI型聚氨酯弹性体,并对弹性体的结构和性能进行表征。结果表明,环氧树脂改性MDI型聚氨酯弹性体中存在嗯唑烷酮结构,提高了弹性体的热分解温度和耐热性能,但弹性体的动态性能变差,微相分离程度变弱。  相似文献   

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以异佛尔酮二异氰酸酯(IPDI)、聚乙二醇(PEG)、环氧树脂E-51为主要原料,合成了聚氨酯预聚体接枝改性的环氧树脂,并以改性环氧树脂作为乳化剂,乳化环氧树脂E-51,通过相反转法制备了纳米级的非离子型水性环氧-聚氨酯乳液。采用红外光谱(FT-IR)对改性环氧树脂进行结构表征,通过纳米粒度分析仪和透射电镜(TEM)研究了乳液的粒径和形貌,同时研究了PEG相对分子质量和聚氨酯预聚体用量对乳液稳定性、粒径的影响。结果表明:当PEG相对分子质量为6 000,聚氨酯预聚体含量为20%时,制备的水性环氧-聚氨酯乳液的综合性能最佳,此时所制备乳液稳定性好,粒径小于150 nm。  相似文献   

7.
《应用化工》2022,(9):1850-1853
利用甲苯二异氰酸酯(TDI)和聚丙二醇(PPG)合成不同结构的端—NCO聚氨酯(PU)预聚体,然后由聚氨酯预聚体与环氧树脂进行接枝反应,制备聚氨酯改性环氧树脂。研究了聚氨酯预聚体结构和用量对改性环氧树脂力学性能的影响规律。结果表明,当聚醚多元醇选用PPG1000,且TDI∶PPG=2∶1时,制得的聚氨酯预聚体对环氧树脂的增韧效果最好,当ω(PU预聚体)=10%时,改性环氧树脂的应变和拉伸强度分别达到84. 7%和27. 1 MPa,是改性前的30. 47倍和3. 04倍。通过扫描电镜对聚氨酯的增韧机理进行了研究,发现改性前环氧树脂为脆性断裂,聚氨酯改性后的环氧树脂断裂时银纹明显增多,为韧性断裂。  相似文献   

8.
利用甲苯二异氰酸酯(TDI)和聚丙二醇(PPG)合成不同结构的端—NCO聚氨酯(PU)预聚体,然后由聚氨酯预聚体与环氧树脂进行接枝反应,制备聚氨酯改性环氧树脂。研究了聚氨酯预聚体结构和用量对改性环氧树脂力学性能的影响规律。结果表明,当聚醚多元醇选用PPG1000,且TDI∶PPG=2∶1时,制得的聚氨酯预聚体对环氧树脂的增韧效果最好,当ω(PU预聚体)=10%时,改性环氧树脂的应变和拉伸强度分别达到84. 7%和27. 1 MPa,是改性前的30. 47倍和3. 04倍。通过扫描电镜对聚氨酯的增韧机理进行了研究,发现改性前环氧树脂为脆性断裂,聚氨酯改性后的环氧树脂断裂时银纹明显增多,为韧性断裂。  相似文献   

9.
纳米蒙脱土插层聚氨酯改性环氧彩色地坪涂料的研制   总被引:2,自引:0,他引:2  
采用聚氧化丙烯二醇(N-210),甲苯二异氰酸酯(TDI)、有机纳米蒙脱土等为原料,制备了有机蒙脱土纳米插层聚氨酯预聚体,并以此对环氧树脂E-44进行化学改性,根据改性复合材料的力学性能等确定了纳米插层聚氨酯预聚体与环氧树脂配量范围,并以纳米插层聚氨酯改性的环氧树脂为基料,确定了地坪涂料各组分的最佳用量范围,研制出了一种高性能纳米插层聚氨酯改性环氧彩色地坪涂料。  相似文献   

10.
聚氨酯改性环氧树脂的制备及红外光谱分析   总被引:16,自引:0,他引:16  
制备了聚氨酯改性环氧树脂体系,并通过红外光谱分析,研究了异氰酸酯端基的聚氨酯预聚体、扩链剂、环氧树脂及其固化剂之间相互反应的规律。结果表明,聚氨酯、环氧树脂二者之间形成IPN结构过程中,环氧树脂与其固化剂之间发生固化反应;扩链剂1,4-丁二醇对PU预聚体进行扩链;同时TDE-85同PU预聚体之间还发生两相间的化学反应,这可有效地提高2种聚合物之间的相容性和稳定性,从而可以提高环氧树脂性能,达到改性目的。  相似文献   

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Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

14.
A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by 1H MAS NMR. For direct comparison purposes, an SiO2 coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N2 absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.  相似文献   

15.
Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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