熱溶劑法製備石墨烯漿料於壓克力／石墨烯複材之研究

Polyacrylate/Graphene Composites Films from Graphene Dispersions Prepared by Solvothermal Method

陳韻如(Yun-Ju Chen)

指導教授 ： 蔡豐羽

國立臺灣大學/工學院/材料科學與工程學研究所/碩士(2020年)

https://doi.org/10.6342/NTU202003993

摘要

隨著電子元件的急速發展，封裝材料也顯得日益重要。以高分子材料作為封裝的基材有低成本以及易加工的優點。不過，對於脆弱的電子元件來說光是靠軟性材料的保護還不夠，故必須添加填料。石墨烯具有封裝材料所需要的性質如機械強度、不可穿透性等，因此本研究將使用石墨烯當作填料。不過，單層石墨烯容易聚集成為多層石墨烯，喪失掉本來的優秀性質。故本研究利用溶劑插層的方式穩定單層石墨烯，溶劑的選用是表面能與石墨烯十分匹配的 N-乙烯基-2-吡咯烷酮(N-vinylpyrrolidone, NVP)。本實驗利用熱溶劑法，將高濃度的石墨烯漿料在高溫低壓的環境下沸騰，並利用 NVP 蒸氣優於液相的擴散性插層於石墨烯層間。此方法可以減少使用探頭破碎的時間，維持較大的石墨烯片徑，並透過 NVP 的穩定，提升石墨烯在高分子基材中的分散性。殘存的 NVP 分子可以與壓克力單體乙氧基化雙酚 A二丙烯酸酯(ethoxylate bisphenol-A diacrylate, EBAD)在 2,2'-二氰基-2,2'-偶氮丙烷( 2,2’-Azobis(2-methylpropionitrile), AIBN)的自由基起始之下形成共聚物，排除了殘留溶劑造成的缺點，製備出具有封裝潛能的石墨烯高分子複材，其機械性質在1.2wt%石墨烯的添加之下，拉伸強度可以達到 3.348MPa，比純高分子增加了 167%，楊氏係數則高達 21.737MPa，提升了 87.55%。本研究利用熱溶劑法提升石墨烯在單體中的分散性，並維持了片徑，成功地製備出機械性能表現優秀的高分子封裝材料。

關鍵字

石墨烯 ； 高分子複材 ； 機械性能 ； 熱溶劑法 ； 高分子薄膜

並列摘要

This study developed a solvothermal technique for uniformly dispersing high concentrations of pristine graphene in monomers, which via in situ polymerization enabled the fabrication of graphene/polymer composites with excellent encapsulant performance, i.e. low moisture permeability and high mechanical properties. The solvothermal technique facilitated thorough absorption of a good solvent, N-vinyl pyrrolidone (NVP), onto graphene platelets through vapor infiltration aided by the mechanical stirring generated by rapid vaporization of NVP. The solvothermal-treated graphene was able to uniformly dispersed in an acrylate monomer, ethoxylate bisphenol-A diacrylate (EBAD), in high concentrations ranging from 0.5 to 1.4wt%. The solvothermaltreated graphene retained its original aspect ratio, as opposed to the severe reduction caused by the conventional ultrasonication dispersion methods. Thanks to the preserved aspect ratio and uniform dispersion of the solvothermal-treated graphene, the resultant composite with the NVP-EBAD copolymer showed marked improvements in moisture transmission rate (from 16.051 to 1.614 𝑔/𝑚2 ⋅ 𝑑 ) and Young’s modulus (from 15.132 to 21.737 MPa) compared with the unreinforced copolymer.

並列關鍵字

graphene ； nanocomposites ； solvothermal method ； water vapor transmission rate ； encapsulation ； mechanical properties

參考文獻

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