高等学校化学学报 ›› 2019, Vol. 40 ›› Issue (6): 1293-1300.doi: 10.7503/cjcu20190045

• 高分子化学 • 上一篇    下一篇

纳米木质素/二氧化硅基微胶囊的制备及在自愈合涂层中的应用

李岚, 钱勇(), 杨东杰, 邱学青   

  1. 华南理工大学化学与化工学院, 制浆造纸工程国家重点实验室, 广州 510640
  • 收稿日期:2019-01-15 出版日期:2019-06-10 发布日期:2019-04-04
  • 作者简介:

    联系人简介: 钱 勇, 男, 博士, 研究员, 主要从事木质素资源化利用的研究. E-mail: ceyqian@scut.edu.cn

  • 基金资助:
    国家自然科学基金(批准号: 21878113, 21606089, 21436004)、 广州市珠江科技新星项目(批准号: 201806010139)和中央高校基本科研业务费(批准号: 2018JQ05)资助.

Preparation of Lignin/silica Nanoparticle Based Microcapsules and Their Application in Self-healing Coatings

LI Lan, QIAN Yong(), YANG Dongjie, QIU Xueqing   

  1. School of Chemistry and Chemical Engineering, State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
  • Received:2019-01-15 Online:2019-06-10 Published:2019-04-04
  • Supported by:
    † Supported by the National Natural Science Foundation of China(Nos. 21878113, 21606089, 21436004), the Guangzhou Science and Technology Research Project of China(No. 201806010139) and the Fundamental Research Funds for the Central Universities of China(No. 2018JQ05).

摘要:

利用磷酸化改性木质素/二氧化硅复合纳米颗粒(PAL/SiO2)作为壁材包埋活性组分异佛尔酮二异氰酸酯(IPDI)制备微胶囊(PAL/SiO2-IPDI). 通过加入少量反应活性更高的聚合多甲基多二异氰酸酯(PMDI), 与水反应形成聚脲, 以增加微胶囊的壁厚. 采用光学显微镜、 扫描电子显微镜(SEM)和激光粒度分析仪(DLS)研究了PAL/SiO2复合纳米粒子掺杂量, 水油比和剪切速率对微胶囊表面形貌、 粒径和壁厚的影响. 结果表明, 所制备的微胶囊呈现规整球形, 壁厚为2.36~3.50 μm, 平均粒径为40.3~201.5 μm. IPDI作为芯材包埋在微胶囊中, 芯材含量约为82.8%. 将制备的PAL/SiO2-IPDI微胶囊添加到环氧树脂中得到自愈合环氧树脂涂层. 其在高盐浓度溶液中的抗侵蚀测试结果显示, 添加质量分数4%的PAL/SiO2-IPDI微胶囊的环氧树脂涂层在划破后能够快速愈合, 显著降低基底的腐蚀电流和腐蚀速率. 纳米压痕实验表明, 环氧涂层的硬度为249.99 MPa, 而添加PAL/SiO2-IPDI微胶囊后硬度增加到302.98 MPa, 弹性模量也有提高.

关键词: 木质素, 二氧化硅, 复合纳米颗粒, 微胶囊, 自愈合涂层

Abstract:

Phosphorylated lignin/silica nano composites(PAL/SiO2) were used as shell material to encapsulate active isophorone diisocyanate(IPDI) to prepare microcapsules(PAL/SiO2-IPDI). A small amount of polymeric methane diisocyanate(PMDI) with more reactivity was added to react with residual water to form polyurea, which could effectively increase the wall thickness of the microcapsules and improve the stability of the system. The effects of PAL/SiO2 nano composite content, water-oil ratio and shearing rate on the morphology, particle size and wall thickness of microcapsules were studied by optical microscopy(OM), scanning electron microscopy(SEM) and dynamic light scattering(DLS). The results show that the prepared PAL/SiO2-IPDI microcapsules were spherical with a wall thickness of 2.36—3.50 μm and an average diameter of 40.3—201.5 μm under optimum preparation conditions. Fourier transformed infrared spectroscopy(FTIR) and thermogravimetric analysis(TGA) revealed that the healing agent IPDI was successfully embedded as a core material in the microcapsules with a content of approximately 82.8%. The PAL/SiO2-IPDI microcapsules were blended with epoxy resin to prepare self-healing coatings. The anti-corrosion tests in the high salt concentration solution show that the epoxy resin coating containing 4%(mass fraction) PAL/SiO2-IPDI microcapsules could heal quickly after scratching, which significantly reduced the corrosion current and corrosion rate of the iron substrate. SEM images demonstrate that the pure epoxy coating had no sign of healing at the scratching area, while that in the self-healing epoxy coating was filled with cross-linking polymer. In addition, the nano indentation tests show that the hardness value of the epoxy coating increased from 249.99 MPa to 302.98 MPa after adding PAL/SiO2-IPDI microcapsules, and the elastic modulus was also improved.

Key words: Lignin, Silica, Composite nanoparticles, Microcapsule, Self-healing coating

中图分类号: