天堂国产午夜亚洲专区-少妇人妻综合久久蜜臀-国产成人户外露出视频在线-国产91传媒一区二区三区

當(dāng)前位置:主頁 > 科技論文 > 材料論文 >

非共價(jià)鍵改性可逆共價(jià)交聯(lián)網(wǎng)絡(luò)的制備及性質(zhì)研究

發(fā)布時(shí)間:2018-08-26 17:12
【摘要】:基于可逆交聯(lián)反應(yīng)的本征型自修復(fù)材料因其能夠自發(fā)的從分子水平上對(duì)材料進(jìn)行修復(fù),延長(zhǎng)材料的使用壽命、拓寬材料的應(yīng)用范圍、降低材料的使用成本而成為研究熱點(diǎn)。共價(jià)鍵相對(duì)于非共價(jià)鍵而言具有更高的鍵能,因此,共價(jià)交聯(lián)聚合物相對(duì)于非共價(jià)交聯(lián)體系來說具有更好的力學(xué)強(qiáng)度,更適合于結(jié)構(gòu)材料的使用。將可逆交聯(lián)反應(yīng)引入共價(jià)交聯(lián)聚合物可得到一類新型的具有自修復(fù)功能的交聯(lián)聚合物。但是由于可逆共價(jià)鍵與傳統(tǒng)共價(jià)鍵相比較小的鍵能,使得可逆交聯(lián)聚合物通常達(dá)不到理想的強(qiáng)度。因此,在提高可逆交聯(lián)聚合物強(qiáng)度的同時(shí)不影響其自修復(fù)效果是目前尚待解決的一個(gè)難題。為提高材料的力學(xué)性能,生物體常采用的一種方法為在材料中引入非共價(jià)鍵作為犧牲鍵,當(dāng)受外力作用時(shí),非共價(jià)鍵首先發(fā)生斷裂消耗部分能量而保證了材料不受破壞。采用仿生的方法,在可逆共價(jià)交聯(lián)聚合物中引入非共價(jià)鍵有望進(jìn)一步提高其力學(xué)性能,而非共價(jià)鍵本身具有的可逆特性不會(huì)影響其自修復(fù)效果。本論文以二硫鍵及Zn~(2+)-咪唑配位鍵為基礎(chǔ),設(shè)計(jì)合成了共價(jià)與非共價(jià)雙交聯(lián)聚合物網(wǎng)絡(luò),以及共價(jià)交聯(lián)及非共價(jià)交聯(lián)互穿網(wǎng)絡(luò)兩種交聯(lián)聚合物體系來研究非共價(jià)鍵的引入以及非共價(jià)交聯(lián)在可逆共價(jià)交聯(lián)網(wǎng)絡(luò)中的引入方式對(duì)可逆共價(jià)交聯(lián)聚合物的影響,采用核磁共振儀、傅里葉紅外光譜儀、熱重分析儀、動(dòng)態(tài)機(jī)械熱分析儀、偏光顯微鏡、掃描電子顯微鏡、萬能試驗(yàn)機(jī)等測(cè)試手段對(duì)聚合物的結(jié)構(gòu)、熱力學(xué)性能、表面形態(tài)、力學(xué)性能及自修復(fù)性能等進(jìn)行了表征和分析,期望為具有良好力學(xué)性能和修復(fù)效果的交聯(lián)聚合物的開發(fā)提供新的思路。具體研究?jī)?nèi)容如下:首先采用聚丙二醇二縮水甘油醚(ppgdge)及1-(3-氨基丙基)咪唑(api)以2:1的摩爾比反應(yīng)得到含咪唑基團(tuán)及端環(huán)氧基的二聚體,隨后通過zn~(2+)與咪唑形成配位鍵非共價(jià)交聯(lián),再利用4’4-二氨基二苯二硫醚(afd)為固化劑與環(huán)氧基團(tuán)進(jìn)行開環(huán)反應(yīng)得到雙交聯(lián)網(wǎng)絡(luò),同時(shí)合成了不含zn~(2+)-咪唑非共價(jià)交聯(lián)的可逆共價(jià)交聯(lián)網(wǎng)絡(luò)作為對(duì)比。利用核磁、紅外等手段證明了雙交聯(lián)網(wǎng)絡(luò)的化學(xué)結(jié)構(gòu)。采用tga、dma、萬能試驗(yàn)機(jī)等研究了雙交聯(lián)網(wǎng)絡(luò)的熱力學(xué)和力學(xué)性能。實(shí)驗(yàn)結(jié)果表明非共價(jià)鍵的引入大大提高了聚合物的力學(xué)性能,循環(huán)拉伸測(cè)試說明了力學(xué)性能提高的原因在于非共價(jià)鍵對(duì)外力作用的能量耗散。利用偏光顯微鏡及萬能試驗(yàn)機(jī)測(cè)試了雙交聯(lián)網(wǎng)絡(luò)在斷裂后的修復(fù)性能。實(shí)驗(yàn)結(jié)果表明在高溫時(shí),由于二硫鍵及金屬配位鍵均發(fā)生交換反應(yīng),所以雙交聯(lián)網(wǎng)絡(luò)及共價(jià)交聯(lián)網(wǎng)絡(luò)均表現(xiàn)出良好的修復(fù)性能。在溫度較低時(shí),共價(jià)交聯(lián)網(wǎng)絡(luò)由于二硫鍵不能發(fā)生交換反應(yīng),所以不能進(jìn)行修復(fù),而雙交聯(lián)網(wǎng)絡(luò)由于非共價(jià)鍵的交換反應(yīng)則恢復(fù)了部分力學(xué)性能,證明了非共價(jià)鍵有利于聚合物材料的自修復(fù)。重塑實(shí)驗(yàn)則表明了雙交聯(lián)網(wǎng)絡(luò)及共價(jià)交聯(lián)網(wǎng)絡(luò)在徹底破壞后均能重復(fù)加工,達(dá)到降低材料使用成本的目的。其次,為充分發(fā)揮可逆共價(jià)(rcn)及可逆非共價(jià)(rncn)兩種交聯(lián)網(wǎng)絡(luò)的優(yōu)勢(shì),制備了具有互穿網(wǎng)絡(luò)結(jié)構(gòu)的聚合物(IPN),研究了RCN及RnCN在互穿網(wǎng)絡(luò)中所占含量不同對(duì)IPN性能的影響。采用SAXS和SEM等表征了IPN的結(jié)構(gòu),采用TGA、DMA及萬能試驗(yàn)機(jī)等對(duì)其熱力學(xué)性能和自修復(fù)性能等進(jìn)行了測(cè)試。結(jié)果表明:IPN的Tg介于RCN和Rn CN之間,說明兩者具有良好的相容性;SAXS的測(cè)試顯示IPN與RCN和RnCN出現(xiàn)同樣的規(guī)律,表明IPN并未發(fā)生微相分離;SEM也表明RCN與RnCN共混后形成了均一體系。循環(huán)拉伸試驗(yàn)發(fā)現(xiàn),樣品受外力作用時(shí),非共價(jià)交聯(lián)網(wǎng)絡(luò)首先受到破壞,而保證共價(jià)交聯(lián)網(wǎng)絡(luò)的完整,達(dá)到較好的增韌效果。純RCN的斷裂伸長(zhǎng)率為44.1%,隨著Rn CN含量的增多,斷裂伸長(zhǎng)率達(dá)200%。修復(fù)測(cè)試表明RCN修復(fù)48h后修復(fù)效率僅達(dá)80%左右,而IPN在同樣條件下修復(fù)12h,修復(fù)效率即可達(dá)90%以上。本章研究表明,將可逆共價(jià)及可逆非共價(jià)交聯(lián)網(wǎng)絡(luò)以互穿網(wǎng)絡(luò)的形式結(jié)合同樣可以起到增強(qiáng)力學(xué)性能及提高修復(fù)效率的目的。
[Abstract]:The intrinsic self-repairing materials based on reversible cross-linking reaction have become a research hotspot because they can repair materials spontaneously at the molecular level, prolong the service life of materials, broaden the application range of materials, and reduce the cost of materials. Compared with non-covalent crosslinking systems, compounds have better mechanical strength and are more suitable for the use of structural materials. A new class of self-repairing crosslinked polymers can be obtained by introducing reversible crosslinking reaction into covalent crosslinking polymers. However, reversible covalent bonds have less bond energy than traditional covalent bonds, which makes reversible crosslinking possible. It is a difficult problem to improve the strength of reversible crosslinked polymers without affecting their self-repairing effect. In order to improve the mechanical properties of materials, a method of introducing non-covalent bonds into materials as sacrificial bonds is often adopted by organisms. The covalent bond breaks first and consumes part of the energy to ensure that the material is not destroyed. The introduction of non-covalent bonds into reversible covalent crosslinked polymers by biomimetic method is expected to further improve their mechanical properties, but the reversibility of the non-covalent bond itself will not affect its self-healing effect. Based on coordination bonds, covalent and non-covalent crosslinked polymer networks and covalent crosslinked and non-covalent crosslinked interpenetrating networks were designed and synthesized to study the effect of the introduction of non-covalent bonds and the introduction of non-covalent crosslinking in reversible covalent crosslinking networks on reversible covalent crosslinked polymers. The structure, thermodynamic properties, surface morphology, mechanical properties and self-repairing properties of the polymer were characterized and analyzed by means of magnetic resonance, Fourier transform infrared spectroscopy, thermogravimetric analysis, dynamic mechanical thermal analysis, polarizing microscope, scanning electron microscope and universal testing machine. The specific research contents are as follows: firstly, the dimer containing imidazole group and epoxy-terminated group was synthesized by the reaction of polypropylene glycol diglycidyl ether (ppgdge) and 1 - (3-aminopropyl) imidazole (api) at the molar ratio of 2:1, and then non-covalent cross-linking of imidazole with Zn ~ (2 +) was formed. A reversible covalent crosslinking network without Zn ~ (2 +) - imidazole was synthesized by ring-opening reaction of 4'4-diaminodiphenyl disulfide (afd) with epoxy group as curing agent. The chemical structure of the network was proved by means of nuclear magnetic resonance and infrared spectroscopy. The thermodynamics and mechanical properties of the bi-crosslinking network were investigated. The results showed that the introduction of non-covalent bonds greatly improved the mechanical properties of the polymer. The cyclic tensile test showed that the reason for the improvement was the energy dissipation of the non-covalent bonds. The experimental results show that at high temperatures, disulfide bonds and metal coordination bonds exchange reactions, so the double cross-linking network and covalent cross-linking network show good repair performance. At low temperatures, covalent cross-linking network can not be repaired because disulfide bonds can not exchange reactions, but double cross-linking. The network restored some mechanical properties due to the exchange reaction of non-covalent bonds, which proved that non-covalent bonds were conducive to self-repairing of polymer materials. The remodeling experiments showed that both the bi-crosslinking network and the covalent crosslinking network could be reprocessed after being completely destroyed, so as to reduce the cost of material use. Secondly, in order to give full play to the reversible covalent network. Polymers (IPN) with interpenetrating network structure were prepared by using valence (rcn) and reversible non-covalence (rncn) crosslinking networks. The effects of different contents of RCN and RnCN in IPN on the properties of IPN were studied. The structure of IPN was characterized by SAXS and SEM, and its thermodynamic properties and self-repairing properties were characterized by TGA, DMA and universal testing machine. The results show that the Tg of IPN is between RCN and RnCN, indicating that they have good compatibility; SAXS test shows that IPN and RCN and RnCN have the same rule, indicating that IPN does not have microphase separation; SEM also shows that the blend of RCN and RnCN forms a homogeneous system. The breaking elongation of pure RCN was 44.1%. With the increase of Rn CN content, the breaking elongation reached 200%. The repair test showed that the repair efficiency of RCN was only about 80% after 48 hours, while that of IPN was about 12 hours under the same conditions. The research in this chapter shows that the combination of reversible covalent and reversible non-covalent crosslinking networks in the form of IPN can also enhance the mechanical properties and improve the repair efficiency.
【學(xué)位授予單位】:東華大學(xué)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2017
【分類號(hào)】:TB381

【參考文獻(xiàn)】

相關(guān)期刊論文 前9條

1 葉三男;王培;孫陽超;王秀民;李春玲;胡松青;;微膠囊填充型自修復(fù)涂層材料研究進(jìn)展[J];表面技術(shù);2016年06期

2 柴云;劉祥萱;王煊軍;李軍;劉博;;基于非離子復(fù)合乳化劑自修復(fù)微膠囊的制備[J];科學(xué)技術(shù)與工程;2016年14期

3 段景寬;江文斌;邵雙喜;江平開;;互穿網(wǎng)絡(luò)聚合物研究及其應(yīng)用進(jìn)展[J];工程塑料應(yīng)用;2010年07期

4 閆超;王汝敏;程雷;黨婧;;互穿聚合物網(wǎng)絡(luò)的研究與應(yīng)用進(jìn)展[J];中國(guó)膠粘劑;2009年10期

5 吳婷;文秀芳;皮丕輝;程江;楊卓如;;互穿網(wǎng)絡(luò)聚合物的研究進(jìn)展及應(yīng)用[J];材料導(dǎo)報(bào);2009年09期

6 謝祥林;徐滿才;高淑芹;廖素芳;;聚乙烯醇/聚苯乙烯互穿聚合物網(wǎng)絡(luò)合成與溶脹性能研究[J];湖南師范大學(xué)自然科學(xué)學(xué)報(bào);2007年04期

7 鐘約先,袁朝龍,馬慶賢;材料內(nèi)部裂紋自修復(fù)中組織生長(zhǎng)機(jī)制[J];清華大學(xué)學(xué)報(bào)(自然科學(xué)版);2002年04期

8 趙曉鵬,周本濂,羅春榮,王景華,劉建偉;具有自修復(fù)行為的智能材料模型[J];材料研究學(xué)報(bào);1996年01期

9 李建保;跨世紀(jì)的智能新材料──現(xiàn)狀與未來[J];自然辯證法研究;1995年10期

相關(guān)碩士學(xué)位論文 前1條

1 張雅蓮;自愈合聚酰胺基聚合物的制備與研究[D];華南理工大學(xué);2013年



本文編號(hào):2205597

資料下載
論文發(fā)表

本文鏈接:http://www.sikaile.net/kejilunwen/cailiaohuaxuelunwen/2205597.html


Copyright(c)文論論文網(wǎng)All Rights Reserved | 網(wǎng)站地圖 |

版權(quán)申明:資料由用戶ddcd5***提供,本站僅收錄摘要或目錄,作者需要?jiǎng)h除請(qǐng)E-mail郵箱bigeng88@qq.com