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1.
研究了采用梯度IPNs方法提高环氧树脂的冲击性能,设计了新型梯度组分分布数学模型描述梯度组分的分布,采用梯度因子和梯度层数控制梯度IPNs的结构变化。并采用逐层浇铸的方法制备了不同种类的环氧/聚氨酯(EP/PU)梯度互穿网络聚合物(IPNs)材料,同时对其冲击性能进行了研究。研究结果表明,梯度结构的变化对其冲击性能有所影响,梯度层数越多,梯度因子越大,梯度IPNs的冲击强度越大。在质量比相同的情况下,梯度IPNs的冲击性能要高于普通IPNs和环氧。  相似文献   

2.
通过高聚物分子设计的方法,运用互穿网络(IPN)技术,以吸水倍率为1.7的甲基丙烯酸β-羟乙酯(HEMA)水凝胶为基体材料,以吸水倍率为7~8的交联N-乙烯基吡咯烷酮(PVPP)颗粒为分散相,制备出了互穿程度不同的复合水凝胶角膜接触镜材料。利用SEM和TG分析仪对合成物的结构及热稳定性进行了表征。结果表明,m(PVPP颗粒)∶m(单体HEMA)=10∶90,以w(甘油或PEG400)=35%~45%作致孔剂,通过控制液体HEMA在PVPP颗粒中的渗透程度,可制得膨润率2%~5.3%、拉伸强度430~695 kPa、透光率>92%、含水质量分数45%左右的中等含水量的复合水凝胶角膜接触镜材料。DTG分析发现,在20~40℃,复合水凝胶的脱水速率随着互穿网络程度的提高而降低。  相似文献   

3.
环氧树脂/聚氨酯梯度聚合物的弯曲性能研究   总被引:1,自引:0,他引:1  
考察了不同层数的环氧树脂/聚氨酯(EP/PU)梯度聚合物弯曲性能,采用有限元法分析了材料在弯曲状态下的应力分布,从理论上解释了EP/PU梯度材料弯曲性能的试验结果,并与相同组成的均质材料进行了比较.研究发现:EP/PU梯度材料的弯曲强度和模量随梯度层数的增加而增加,当梯度层数超过5层以后,EP/PU梯度材料的弯曲强度高于相同组成的均质材料.有限元分析结果表明:在EP/PU梯度材料中,应力的分布与各层材料承受的强度相匹配,即应力大的部位材料的强度也越大.梯度层越多,各层之间强度变化越小,应力变化越为缓和,且应力分布与材料强度之间匹配越好,在受外力时,材料断裂强度越高.梯度材料中应力分布方式的理论计算结果很好的解释了实测的各种梯度材料强度变化规律.  相似文献   

4.
聚丙烯酸酯改性聚氨酯复合乳液研究进展   总被引:1,自引:0,他引:1  
朱宁香  叶代勇  陈焕钦 《化工进展》2007,26(10):1419-1424
总结了聚丙烯酸酯改性聚氨酯(PUA)复合乳液(包括PUA共混乳液、PUA共聚乳液、PUA核壳结构乳液、PUA互穿网络乳液)的制备方法和性能特点,详细介绍了近年来PUA复合乳液的新进展,并对PUA复合乳液的发展作了一些展望。  相似文献   

5.
介绍了聚合物阻尼材料的分子设计;论述了共聚物的分子设计、阻尼微结构、梯度阻尼结构等;综述了聚合物阻尼材料复合改性的研究进展。对共混及互穿聚合物网络、有机/无机杂化体系、纳米复合体系和聚合物/小分子复合体系等进行了述评。  相似文献   

6.
穆中国  王源升 《塑料工业》2007,35(B06):171-173
设计了一种新的梯度组分分布数学模型,采用梯度因子和梯度层数控制梯度组分的分布,并采用逐层浇铸的方法制备了不同层数的EP/PU梯度互穿网络聚合物(IPN)材料;测试了材料的拉伸性能、弯曲性能以及冲击性能;研究了梯度层数变化对这些性能的影响,并同普通IPN的性能进行了对比。研究结果表明,在相同质量比和梯度因子情况下,梯度层数越多,拉伸强度和冲击强度越高,弯曲强度越低。梯度IPN的拉伸强度和冲击强度均高于普通IPN,弯曲强度低于普通IPN。  相似文献   

7.
通过就地乳液聚合方法合成了聚丙烯酸酯胶乳互穿聚合物网络/蒙脱土纳米复合材料。与纯聚丙烯酸酯胶乳互穿聚合物网络相比,该材料的阻尼性能有较大幅度的提高,蒙脱土的加入提高了互穿聚合物网络中软、硬相的相容性或互穿程度,因此起到了既增强又增韧的效果。  相似文献   

8.
互穿聚合物网络技术在聚氨酯中的应用   总被引:1,自引:1,他引:1  
综述了互穿聚合物网络(IPN)技术在聚氨酯材料中的应用研究进展。简述了聚氨酯IPN的制备,具体叙述环氧树脂、聚丙烯酸酯、聚硅氧烷、乙烯基酯树脂等聚合物与聚氨酯互穿网络改性的效果,并在此基础上展望了聚氨酯互穿网络聚合物的发展趋势。  相似文献   

9.
分析了角膜接触镜对所需高分子材料性能的要求;介绍了角膜接触镜材料的研发历程,特别介绍了仿生材料水凝胶、互穿网络水凝胶、NVP-CS-HEMA半互穿网络水凝胶等新型角膜接触材料及其性能;在材料制备方面,重点讨论了化学引发和光引发技术;最后对本领域的发展进行了展望。  相似文献   

10.
PMMA/P(BA-co-AA)界面交联LIPN阻尼材料的研究   总被引:3,自引:0,他引:3  
晏欣  门金凤  姚树人 《弹性体》2002,12(1):31-34
用种子乳液聚合法合成了PMMA/P(BA-co-AA)界面交联乳胶互穿聚合物网络材料。动态力学谱结果表明,界面交联能提高乳胶互穿聚合物网络的高温阻尼性能;拉伸实验结果表明,界面交联提高了乳胶互穿聚合物网络的抗拉强度和断裂伸长率。  相似文献   

11.
乳聚丁苯互穿网络型热塑性弹性体的制备   总被引:1,自引:0,他引:1  
以丁苯胶乳为种子乳液,苯乙烯、甲基丙烯酸甲酯、丙烯腈或它们的混合物的硬单体,用氧化还原引发体系,经种子乳液聚合法同备出复合乳液,絮凝干燥后所得互穿聚合物网络可热塑性反复加工。考察了硬单体的种类和用量、交联剂的种类及用量、反复加工次数对聚合物力学性能的影响。用透射电子显微镜观察了乳胶粒微观形态,结果表明:用混合单体,聚合物力学性能较优,以35份St^+MMA为第二单体制备的聚合物的攫断伸长率为400%,拉伸强度为9.3MPa,300%定伸应力为7.6MP,撕裂强度为73.9kN.M^-1,邵尔A型硬度为84。  相似文献   

12.
Composite latex particles based on natural rubber latex have been synthesized to yield materials which may be formally regarded as interpenetrating polymer networks and semiinterpenetrating polymer networks. Methyl methacrylate was added to a carefully stabilized natural rubber latex and polymerized in situ using an amine-activated initiator, tert-butyl hydroperoxide. The resulting materials were cast to yield solid sheets. The morphology of the materials was determined both by transmission electron microscopy and by dynamic mechanical analysis. In addition the stress–strain behavior was studied.  相似文献   

13.
功能梯度材料中的渗流现象   总被引:4,自引:0,他引:4  
  相似文献   

14.
互穿聚合物网络阻尼材料研究进展   总被引:16,自引:2,他引:14  
介绍了互穿聚合物网络阻尼材料的研究进展,讨论了对其阻尼性能的评价以及组分、组分间的相容性、交联密度、无机填料等影响性能的因素,并展望了互穿聚合物网络的研究前景。  相似文献   

15.
综述了聚苯乙烯互穿聚合物网络的研究进展,阐述了分步互穿聚合物网络、同步互穿聚合物网络、半互穿聚合物网络和胶乳互穿聚合物网络的制备方法,介绍了组成和制备方法对PS互穿聚合物网络的相态结构和互穿聚合物网络相容性的影响。阐述了PS互穿聚合物网络的组成和结构对于力学性能、热力学性能、流变性能、气体透过率和吸附性的影响,最后综述PS互穿聚合物网络存在的问题及发展趋势。  相似文献   

16.
Four interpenetrating polymer networks were prepared by swelling crosslinked Acronal (a copolymer of styrene and butyl acrylate) with methyl acrylate plus crosslinking agent and then polymerizing the methyl acrylate in situ. Certain properties of the constituent network materials, plus the interpenetrating polymer networks which contained 70, 50, 35 and 25% by weight of polymethyl acrylate, were investigated. Electron microscopy showed the interpenetrating polymer networks to be two-phase materials with the polymethyl acrylate domain size increasing with increasing polymethyl acrylate content. Longitudinal sonic velocity measurements indicate that at around 50% by weight of polymethyl acrylate both phases become continuous while dynamic mechanical spectroscopy leads to the view that the constituent networks were not extensively mixed.  相似文献   

17.
Gradient polymers are multicomponent networks which contain a spatial gradient in the concentration of the components in the blend. In this study, the properties of a system of gradient polymers consisting of a rubbery addition to a glassy matrix [poly(methyl methacrylate)] and a glassy addition to a rubbery matrix [poly(2-chloroethyl acrylate)] were investigated. Dynamic mechanical spectroscopy was used to characterize the compatibility of the polymers. The PMMA matrix gradients were found to be incompatible, while the PCIEA matrix gradients and the interpenetrating network exhibited compatibility. The tensile properties and the fracture strength of the polymers were measured and interpreted in terms of the composition and the deformation mechanism of the materials.  相似文献   

18.
The effects of the PMMA content and the cross‐linker level in the poly(methylmethacrylate) component on the dynamic and physico‐mechanical properties of semi‐2 interpenetrating polymer networks based on natural rubber and poly(methylmethacrylate) were determined. The miscibility of the components in these semi‐2 interpenetrating polymer networks was determined using the loss tangent data, obtained from dynamic mechanical thermal analysis and the interphase contents were calculated from modulated scanning calorimetric data. Some component mixing in these semi‐2 interpenetrating polymer networks was evident from these modulated differential scanning calorimetric and dynamic mechanical thermal analysis data. The degree of component mixing increased with cross‐linker level in the PMMA phase. The PMMA content in the semi‐2 IPNs has a significant effect on the tensile and hysteresis behavior of these semi‐2 interpenetrating polymer networks. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

19.
综述了功能梯度材料的概念、性能、研究动态及最新进展。总结了功能梯度材料的各种制备方法。重点探讨了采用复合电镀技术制备功能梯度材料的方法。该方法成本低,易于操作,所得镀层孔隙率低,结合力好,耐磨,耐蚀性好,具有广阔的应用前景。  相似文献   

20.
Two latex interpenetrating polymer networks, one prepared from a pair of supposedly compatible polymers and the other from an incompatible pair, were investigated using transmission electron microscopy and dynamic mechanical analysis. From the results, it was proposed that both interpenetrating polymer networks consisted of latex particles with essentially coreshell morphologies. Evidence for a core-shell structure was more marked for the materials synthesised from the incompatible polymers. The other polymer pair showed indications of a significant amount of mixing.  相似文献   

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