共查询到19条相似文献,搜索用时 187 毫秒
1.
PMMA/PnBA乳胶IPN阻尼及转变行为的研究EI 总被引:1,自引:1,他引:0
用乳液聚合方法合成了聚甲基丙烯酸甲酯和聚丙烯酸丁酯的互穿聚合物网络(IPN)。动态力学分析结果表明:这种半相容的PMMA/PnBA乳胶IPN在-50°~+60℃温度范围内具有良好的阻尼性能,组成和交联剂用量影响该体系的相容性和阻尼性能。 相似文献
2.
一种新型的粘弹性振动阻尼材料——互穿聚合物网络(IPN) 总被引:2,自引:1,他引:1
本文总结了前人对互穿聚合物网络(IPN)的研究成果。结合我们的研究工作,着重讨论了IPN的微观形态结构、IPN中各组分相容性和IPN的阻尼性能。指出IPN的形成过程是以热力学因素为主导的相分离过程和以动力学因素为主导的互穿过程相互竞争。互穿可增加聚合物间相容性。比较系统地总结了合成IPN阻尼材料的分子设计途径。提出了IPN中高分子结构、分子间氢键及其它结构参数对IPN材料阻尼性能产生影响的基本原因。此外,明确了一些IPN研究中的基本概念以及所用名称的意义。 相似文献
3.
PEMA/PEA自交联乳胶IPN阻尼材料的研究 总被引:5,自引:0,他引:5
利用种子乳液聚合和双丙酮丙烯酰胺与己二酰肼的交联反应合成了PEM A/PEA乳胶IPN。DM S结果表明,组成比对L IPN的相容性和阻尼性能有显著的影响;组成比为35/65的L IPN具有较优异的阻尼性能;界面自交联能改善组分相容性,但使材料的阻尼性能有所下降。拉伸实验结果表明,增加硬组分和交联剂的含量,拉伸强度显著增加。 相似文献
4.
PF/PnBA IPN的合成及相容性研究 总被引:2,自引:0,他引:2
本文采用乳液和溶液聚合法合成PF/PnBA IPN,并对产物进行了动态力学性能、热重分析及微观形态研究。结果表明,IPN可使组分相容性得到提高热性能得以改善,乳液聚合与溶液聚合法合成IPN产物的微观形态有所不同。 相似文献
5.
两类室温固化的蓖麻油聚氨酯互穿网络材料 总被引:2,自引:0,他引:2
研究了五种取代乙烯分别与蓖麻油聚氨酯生成的互穿网络聚合物(IPN)的力学性能与其组成的关系,指出聚氨酯含量在65%左右拉伸强度最大,最大强度与取代乙烯均聚物的玻璃化转变温度有关。NCO/OH比愈大,IPN的交联密度愈大,伸长率愈小,拉仲强度愈大。由丙烯酸丁酯生成的IPN具有弹性体性能。还研究了蓖麻油聚氨酯与不饱和聚酯及取代乙烯生成的IPN,指出丙烯腈作为取代乙烯所得的IPN性能最好,不饱和聚酯与丙烯腈的重量比不宜超过1/1。后一IPN的扫描电镜照片表明具有微观相分离的形态结构。 相似文献
6.
聚甲基丙烯酸甲酯/聚丙烯酸正丁酯(PMMA/PnBA)乳胶IPN的相容性较差,从溶度参数和结构等方面考虑,有目的地选择单体与nBA共聚,合成了一系列PMMA/P(nBA—co—Y)乳胶IPN,测定了其动态力学性能。结果表明,乳胶体系的相容性有明显改善。研究还表明,共聚单体间的竞聚率影响LIPN的相容性;改变共聚单体的用量可控制LIPN的相容性。还发现,共聚网络具有更好的阻尼特性。 相似文献
7.
PU/VER IPN材料阻尼性能的研究 总被引:10,自引:0,他引:10
采用DMA法研究了热力学、动力学因素及组成比对聚氨酯/乙烯基酯树脂互穿聚合物网络(PU/VER IPN)材料阻尼性能的影响。研究发现:引入丙烯酸酯类单体为VER共聚单体,改善了常规以苯乙烯(St)为共聚单体的PU/VER(St)IPN材料的阻尼性能,含较长酯基的体系具有更优的阻尼性能;通过调整两网络的相对聚合速率及组成比,可使材料出现宽温域阻尼,合成的组成比为80/20、70/30及60/40的IPN材料,在至少近80℃的温域,阻尼因子(tanδ)>0.3。进一步通过TEM检测分析了IPN材料微观结构与阻尼性能的关系。 相似文献
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聚氨酯/环氧树脂互穿聚合物网络半硬泡沫的结构与性能 总被引:3,自引:0,他引:3
采用同步法合成了聚醚型聚氨酯/环氧树脂互穿聚合物网络半硬泡沫.通过FTIR,DMA,SEM研究了IPN半硬泡沫的化学结构、动态力学性能以及微观结构形态.FTIR分析表明了聚氨酯和环氧树脂的网络间存在接枝反应.很宽组成比范围内IPN半硬泡沫均显示出单一的宽温域玻璃化转变,而且该转变随着环氧树脂含量的增加向高温方向移动.通过SEM发现IPN半硬泡沫泡孔结构形状都比较均一.循环加载压缩发现所有IPN泡沫不仪压缩性能好而且具有很好的回弹性,大变形压缩后泡沫儿乎不变形,重复使用性能好. 相似文献
10.
由聚氨酯(聚四氢呋喃醚、液化MDI)、端羟基聚硅所烷齐聚物室温催化合成的一系列的聚氨酯/聚硅氧烷IPN阻尼弹性体。其中拉伸强度最佳值Ts=46.0MPa,断裂伸长率E=430%,同时,tanδ>0.3的温度范围高于30℃。研究认为,由齐聚物在室温交联形成IPN可以较有效地阻止进一步相分离。FTIR发现IPN中聚氨酯和聚硅氧烷网络之间没有化学键形成,聚氨酯的交联反应仍为二级反应,但形成速率降低了两个数量级。SEM、AFM和XPS研究表明,含少量苯基侧基聚二甲基硅氧烷与聚氨酯有良好的相容性,在IPN中形成微米级微结构;聚醚分子量对聚氨酯的软硬链段比例和网络交联密度以及IPN的形态结构和性能都有很大影响;XPS研究发现,主要元素C、N、Si、O在IPN的表面和内部的分布是不均匀的,聚硅氧烷趋向于分面IPN的表面。TG-IR分析聚氨酯/聚硅氧烷IPN的热裂解行为发现,聚硅氧烷的加入提高了IPN的热稳定性,聚氨酯/聚硅氧烷IPN的热裂解机理与纯聚氨酯和聚硅氧烷的热裂解机理一致。聚氨酯/聚硅氧烷IPN由于具有高强度阻尼弹性体的力学特征,同时具备优良的耐热、耐溶剂性,具有潜在的特殊应用前景。 相似文献
11.
光固化型聚氨酯/环氧树脂IPN的制备与表征 总被引:8,自引:0,他引:8
采用IPN技术,制备了一系列光固化型的聚氨酯与环氧树脂的IPN树脂,经力学性能测试表明当PU/EP=70/30时,IPN的断裂伸长率达160%。,拉伸强度比纯PU提高210%,显示出良好的正协同效应。利用红外光谱,光谱微镜,应力-应变,硬度等测试手段对PU/EP的互穿网络的结构:两组分的相容性,微相分离的形态结构进行了表征。并且探讨了IPN的结构与力学性能之间的关系及影响因素,认为:PU/EP的I 相似文献
12.
Jacob John R. Suriyakala Selvin Thomas Jude Martin Mendez Anitha Pius Sabu Thomas 《Journal of Materials Science》2010,45(11):2892-2901
Morphology, mechanical properties, thermal stability and gas transport behaviour of interpenetrating polymer networks (IPNs)
based on PI/PMMA have been investigated using various techniques. Crosslinking level of both phases and concentration of PMMA
were found to have noticeable effects on the compatibility of immiscible components during IPN formation. Effect of crosslinking
was studied by preparing IPNs with varying amount of crosslinker concentration in each phase. Crosslinking of both phases
facilitated deeper interpenetrations between both networks, and certain degree of compatibility is attained during IPN formation.
Nanometre-sized domains were observed for highly crosslinked IPN. Lower concentration of PMMA was found to favour phase mixing
more effectively than others. DSC curve of 65/35 IPN showed a broad transition arising from the α and β-relaxations of PMMA
due to the higher flexibility attained by mixing with the highly mobile PI chains. The mechanical properties of the IPNs were
correlated to the morphology of the system and 50/50 composition showed maximum mechanical properties among the studied compositions.
Mode of mechanical failure, thermal stability and gas transport behaviour were also analysed. IPNs having nanometre-sized
domains showed least gas permeability among the studied samples. 相似文献
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研究了三元IPN PU/EP/PBA的形态结构及其影响因素,研究表明,在一定合成条件下,IPN在形态上具有单一均相结构,同时网络关联密度,组分比例,PU的预聚体结构等因素对其形态有重要影响。在此基础上,分析建立了组成-形态-性能关系,并引入后凝胶时间概念对三元IPN中全IPN与半IPN的形态差异作出解释 。 相似文献
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16.
Peng HT Mok M Martineau L Shek PN 《Journal of materials science. Materials in medicine》2007,18(6):1025-1035
This study was conducted to understand the effects of aging methacrylated gelatin solutions on the properties of gelatin-HydroThaneTM Interpenetrating Polymer Network (IPN) films. The latter were prepared from methacrylated gelatin solutions that were either
freshly made or stored at different concentrations and temperatures for various periods. The morphology, swelling stability
and mechanical properties of the IPNs were then accordingly characterized. The IPNs prepared with aged solutions showed a
reduced phase separation; changed from a network-like structure to a continuous phase structure; and demonstrated higher swelling
stabilities and higher elasticity under optimal aging conditions, compared to the IPN prepared with a fresh methacrylated
gelatin solution. An increase in viscosity and a change in phase transition of aged methacrylated gelatin solutions were also
observed, presumably due to the physical structuring of methacrylated gelatin chains (e.g., by the formation of a helix structure),
thus altering the resulting IPN characteristics. A better understanding of the effects of aging methacrylated gelatin solution
on the formation and properties of gelatin-HydroThaneTM IPNs should enable us to further develop our composite biomaterials for different dressing applications. 相似文献
17.
Katharina Sommer Paul Rieger Stefanie Monika Müller Romana Schwarz Gregor Trimmel Michael Feuchter Thomas Griesser 《Advanced Engineering Materials》2023,25(7):2200901
In recent years, dual-cure chemistry has been exploited to realize interpenetrating networks (IPNs) that provide enhanced thermo-mechanical properties. In this contribution, photoinduced curing of (meth)acrylates is used to build the desired 3D structure, whereas the thermally triggered polymerization reaction of 2H-chromene functionalized building blocks is utilized to create the IPN. This strategy combines the advantages of traditional UV-curable monomers with high-performance thermosets. After the successful synthesis of the bispropargyl ether derivative, i.e., 4,4′-(propane-2,2-diyl)bis((ethynyloxy)benzene), its thermally induced conversion to the corresponding 2H chromene functionalized prepolymer is studied by Fourier-transform infrared spectroscopy and gel permeation chromatography. The network formation as well as the printability of various formulations containing different amounts of the thermo-curable building block is investigated. The obtained IPNs provide enhanced thermo-mechanical properties making these resins suitable for the additive manufacturing of functional 3D parts for high-performance applications. 相似文献
18.
环氧树脂/聚氨酯半互穿网络聚合物的研究Ⅰ.玻璃化转变行为及其形态结构 总被引:5,自引:0,他引:5
用分步法制备了环氧树脂/聚氨酯(EP/PU)半IPN,通过差示扫描量热法(DSC)与动态力学分析法(DMA)研究了该半IPN的玻璃化转变行为,用扫描电镜(SEM)表征了其形态结构。结果表明,在此半IPN中,两组分聚合物的玻璃化转变温度(Tg)靠近,并伴随有第三个Tg的出现。该半IPN具有两相结构,两相连续程度随组分量的变化而变化。 相似文献
19.
Gradient interpenetrating polymer networks 总被引:5,自引:0,他引:5
The methods of synthesis and properties of gradient interpenetrating polymer networks (IPN) are discussed based on literature
and authors' own experimental data. Gradient IPN can be treated as a sequence of an infinite number of layers of IPNs, whose
composition and properties vary gradually from the surface to the core of specimens. These are analysed the most important
properties of gradient IPNs: temperature transitions, thermodynamic and physico-mechanical characteristics and the main direction
of practical application of gradient IPN-based materials. 相似文献