本文選題：雙逾滲 + 高分子導(dǎo)電復(fù)合材料��； 參考：《青島大學(xué)》2017年碩士論文

【摘要】：高分子導(dǎo)電復(fù)合材料是將導(dǎo)電填料填充到聚合物基體中而形成的一類具有導(dǎo)電性能的高分子復(fù)合材料。由于具有優(yōu)良的可加工性、可調(diào)控的導(dǎo)電性能以及廣泛的應(yīng)用領(lǐng)域,高分子導(dǎo)電復(fù)合材料受到學(xué)術(shù)界和工業(yè)界的廣泛關(guān)注。然而,目前往往需要向聚合物基體中填充大量的導(dǎo)電填料才能使高分子復(fù)合材料實現(xiàn)由絕緣到導(dǎo)電的轉(zhuǎn)變,這不僅提高了材料的制造成本,也降低了材料的力學(xué)性能和加工性能。因此,如何制備具有超低導(dǎo)電逾滲閾值的高分子導(dǎo)電復(fù)合材料成為人們研究的熱點。研究表明,將導(dǎo)電填料填充到具有雙連續(xù)結(jié)構(gòu)的不相容共混體系中,利用雙逾滲效應(yīng)可以有效地降低高分子導(dǎo)電復(fù)合材料的導(dǎo)電逾滲閾值。但是,由于不相容共混體系中兩相間相容性差,界面黏附力小,具有雙逾滲結(jié)構(gòu)的高分子導(dǎo)電復(fù)合材料的力學(xué)性能存在一定的缺陷。因此,本文主要圍繞如何降低高分子導(dǎo)電復(fù)合材料的導(dǎo)電逾滲閾值并提高其力學(xué)性能開展了一系列的研究工作,主要的研究結(jié)果如下:1.本文設(shè)計了一種簡單、有效的熱力學(xué)方法將多壁碳納米管(MWCNTs)精確地調(diào)控到具有雙連續(xù)結(jié)構(gòu)的聚苯乙烯(PS)/聚甲基丙烯酸甲酯(PMMA)共混體系的相界面,進(jìn)而制得了具有超低導(dǎo)電逾滲閾值的高分子導(dǎo)電復(fù)合材料。這種MWCNTs界面分布的實現(xiàn)是由于MWCNTs表面與PS之間的?-?相互作用和MWCNTs表面的羧基基團(tuán)與PMMA之間的偶極-偶極相互作用的相互平衡。研究發(fā)現(xiàn),當(dāng)MWCNTs表面羧基基團(tuán)的含量為0.73 wt%時,?-?相互作用能夠與偶極-偶極相互作用達(dá)到平衡,此時MWCNTs可以被精確地調(diào)控到PS/PMMA的相界面。由于MWCNTs在雙連續(xù)相的界面形成導(dǎo)電網(wǎng)絡(luò),PS/MWCNTs/PMMA復(fù)合材料的導(dǎo)電逾滲閾值由1.81 wt%(MWCNTs/PS復(fù)合材料的導(dǎo)電逾滲閾值)或1.46 wt%(MWCNTs/PMMA復(fù)合材料的導(dǎo)電逾滲閾值)降低至0.017 wt%,這是目前文獻(xiàn)報道的一個非常低的導(dǎo)電逾滲閾值。2.本文利用雙逾滲效應(yīng)制備了導(dǎo)電逾滲閾值為1.45 wt%的炭黑(CB)/PS/聚丙烯(PP)(PS/PP=60 w/40 w)高分子導(dǎo)電復(fù)合材料。然而,由于PS、PP不相容共混體系的界面黏附力弱,CB/PS/PP(60 w/40 w)高分導(dǎo)電復(fù)合材料的力學(xué)性能較差。盡管增容劑聚(苯乙烯-乙烯-丁烯-苯乙烯)(SEBS)三嵌段共聚物的添加可以顯著地提高復(fù)合材料的力學(xué)性能,但是當(dāng)SEBS的含量超過3 wt%時,該復(fù)合材料的導(dǎo)電性能卻大幅度降低。這是由于增容劑SEBS的加入會減小不相容共混體系的相尺寸,進(jìn)而破壞雙逾滲結(jié)構(gòu)中的兩相連續(xù)性。研究發(fā)現(xiàn),當(dāng)SEBS的含量為2 wt%時,CB/SEBS/PS/PP(60 w/40 w)復(fù)合材料仍然保持著較好的雙逾滲結(jié)構(gòu),材料不僅具有優(yōu)異的導(dǎo)電性能,而且其力學(xué)性能也得到顯著地提高。因此,通過加入適量的增容劑SEBS(2 wt%)可以很好地平衡具有雙逾滲結(jié)構(gòu)的CB/SEBS/PS/PP(60 w/40 w)高分子導(dǎo)電復(fù)合材料的導(dǎo)電性能和力學(xué)性能。
[Abstract]:Polymer conductive composite is a kind of conductive polymer composite which is filled with conductive filler in polymer matrix. Due to its excellent processability, controllable conductivity and wide application fields, polymer conductive composites have attracted extensive attention from academia and industry. However, it is often necessary to fill the polymer matrix with a large number of conductive fillers in order to achieve the transition from insulation to conductivity in polymer composites, which not only increases the cost of manufacturing materials. The mechanical properties and processing properties of the materials are also reduced. Therefore, how to prepare polymer conductive composites with ultra-low percolation threshold has become a hot research topic. The results show that the double percolation effect can effectively reduce the percolation threshold of polymer conductive composites by filling conductive fillers into incompatible blends with double continuous structure. However, the mechanical properties of polymer conductive composites with double percolation structure have some defects due to the poor compatibility between the two phases and the small adhesion between the two phases in the incompatible blends. Therefore, this paper focuses on how to reduce the percolation threshold and improve the mechanical properties of polymer conductive composites. The main results are as follows: 1. In this paper, a simple and effective thermodynamic method has been designed to precisely regulate the multi-walled carbon nanotubes (MWCNTs) to the phase interface of polystyrene (PS) / polymethyl methacrylate (PMMA) blends with double continuous structure. Furthermore, polymer conductive composites with ultra-low percolation threshold were prepared. The realization of the interfacial distribution of MWCNTs is due to the interfacial distribution between MWCNTs and PS. The equilibrium of the dipole-dipole interaction between the carboxyl groups on the surface of MWCNTs and PMMA. It was found that when the content of carboxyl group on the surface of MWCNTs was 0.73 wt%, the content of carboxyl group was 0.73 wt%. The interaction can reach equilibrium with dipole-dipole interaction, where MWCNTs can be accurately regulated to the phase interface of PS- / PMMA. The percolation threshold of PS / MWCNTs / PMMA composites decreased from 1.81 wt% (the percolation threshold of MWCNTs / PMMA) or 1.46 wt% (the percolation threshold of MWCNTsP / PMMA) to 0.017 wts. this is the current literature. A very low percolation threshold. 2. In this paper, the conductive composites of carbon black (CB) / PS / PP (PS / PP) (60 w/ 40 w) with conductive percolation threshold of 1.45 wt% were prepared by double percolation effect. However, the interfacial adhesion of PS / PP / PP / PP (60 w / 40 w) high content conductive composites is poor because of the weak interfacial adhesion. Although the addition of the compatibilizer (styrene butene styrene) triblock copolymers can significantly improve the mechanical properties of the composites the electrical conductivity of the composites decreases significantly when the content of SEBS exceeds 3 wt%. This is because the addition of compatibilizer SEBS will reduce the phase size of the incompatible blend system and thus destroy the two-phase continuity in the double-percolation structure. It is found that when the content of SEBS is 2 wt%, CBP / SEBS / PS / PP (60 w/ 40 w) composites still maintain a good double percolation structure. The composites not only have excellent electrical conductivity, but also their mechanical properties have been significantly improved. Therefore, by adding proper amount of compatibilizer SEBS (2 wt%), the conductive and mechanical properties of CB/ SEBS / PS-PP / PP (60w / 40w) composites with double percolation structure can be well balanced.
【學(xué)位授予單位】：青島大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TB332

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 ;Electrical conductivities of carbon nanotube-filled polycarbonate/polyester blends[J];Science China(Chemistry);2012年05期

，

本文編號：2089360