本文關(guān)鍵詞：氯離子觸發(fā)的有機(jī)無機(jī)復(fù)合壁材微膠囊的制備及性能研究　出處：《深圳大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 化學(xué)觸發(fā) 自修復(fù)混凝土 復(fù)合壁材微膠囊 氯離子

【摘要】：氯離子是引起混凝土中鋼筋銹蝕的主因。如果采用氯離子敏感微膠囊將氯離子吸收劑、鋼筋阻銹劑或者修復(fù)劑預(yù)埋在混凝土中,就可以減緩氯離子在混凝土中的滲透,阻斷其到達(dá)鋼筋表面的擴(kuò)散途徑,提高了這些工程在高鹽環(huán)境下的耐久性,產(chǎn)生巨大的經(jīng)濟(jì)效益和社會效益。本文設(shè)計和制備了氯離子觸發(fā)離子的微膠囊。該微膠囊的壁材為嵌有不溶性金屬無機(jī)鹽顆粒的憎水性聚合物。在無氯水中,該微膠囊很穩(wěn)定。在含氯離子的水中,囊壁上無機(jī)鹽的金屬離子因與氯離子絡(luò)合,生成可溶性絡(luò)合離子而離去,在囊壁上留下細(xì)孔,使水滲入,芯材溶脹而使微膠囊破裂,實現(xiàn)化學(xué)觸發(fā)功能。選用硫酸鉛和氯化亞銅為觸發(fā)源,采用溶劑蒸發(fā)法,分別制備了以十六烷為芯材,嵌有硫酸鉛的聚甲基丙烯酸甲酯為壁材的微膠囊(Hexadecane/Pb SO4-PMMA),和以環(huán)氧樹脂E-51為芯材,嵌有氯化亞銅的聚苯乙烯為壁材的微膠囊(E-51/Cu Cl-PS)。研究了芯壁比、攪拌速率、乳化劑種類與濃度等對膠囊性能的影響,優(yōu)化了這兩種復(fù)合壁材微膠囊的制備工藝。利用光學(xué)顯微鏡(OM)、掃描電子顯微鏡(SEM)、傅里葉紅外(FTIR)、差熱分析儀(DSC)、熱重分析儀(TGA)和X射線衍射(XRD)對微膠囊的形貌和結(jié)構(gòu)進(jìn)行了表征。結(jié)果表明,在制備過程中,原料配比、蒸發(fā)溫度、攪拌速率、表面活性劑種類及用量等對微膠囊的形貌和結(jié)構(gòu)都有很大的影響,其中乳化劑的種類和用量、攪拌速率,主要影響了微膠囊囊壁上金屬無機(jī)鹽顆粒的粒徑大小、嵌入量分布和分布。實驗優(yōu)化了微膠囊的制備工藝,當(dāng)芯壁比為1.5:1~1:1,攪拌速率為400rpm左右,表面活性劑為PVA,濃度為5%,蒸發(fā)溫度為40℃,蒸發(fā)時間為2~3h時,獲得微膠囊性能較佳。在該工藝條件下,金屬無機(jī)鹽顆粒在壁材中分散液很均勻,制得的微膠囊的平均粒徑為150μm,且分布較窄。納米壓痕儀測得,Hexadecane/Pb SO4-PMMA微膠囊壁材的彈性模量為2.504Gpa,硬度為0.036Gpa;E-51/Cu Cl-PS微膠囊壁材的彈性模量為2.01Gpa,硬度為0.029 GPa。在模擬海水中的觸發(fā)試驗表明,Hexadecane/Pb SO4-PMMA微膠囊和E-51/Cu Cl-PS微膠囊壁在水溶液中對氯離子均有很好的響應(yīng),響應(yīng)時間分別為5小時和1小時。若氯鹽濃度增加,則響應(yīng)時間縮短。
[Abstract]:Chloride ion is the main cause of corrosion of steel bars in concrete. If chloride ion sensitive microcapsules are used to pre-bury chloride ion absorbent, corrosion inhibitor or repair agent in concrete. It can slow down the penetration of chloride ions in concrete, block the diffusion of chloride ions to the surface of steel bar, and improve the durability of these projects in high salt environment. In this paper, we designed and prepared the microcapsule which is triggered by chloride ion. The wall material of the microcapsule is hydrophobic polymer with insoluble metal inorganic salt particles. The microcapsule is very stable. In the water containing chloride ions, inorganic salt metal ions in the capsule wall are complexed with chloride ions to form soluble complex ions, leaving fine pores in the wall of the capsule to make water permeate. When the core material was swelled, the microcapsule was broken and the chemical trigger function was realized. Using lead sulfate and cuprous chloride as trigger source, hexadecane as core material was prepared by solvent evaporation method. Hexadecane / Pb SO4-PMMAA and epoxy resin E-51 were used as core materials for microencapsulation of polymethyl methacrylate with lead sulfate as wall material. The effects of core wall ratio, stirring rate, type and concentration of emulsifier on the properties of the microcapsules were studied. The preparation process of these two kinds of composite wall microcapsules was optimized by optical microscope, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and differential thermal analyzer (DSCS). The morphology and structure of microcapsules were characterized by thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The types and dosage of surfactants have a great influence on the morphology and structure of microcapsules. The type and dosage of emulsifiers and stirring rate mainly affect the particle size of metal inorganic salt particles on the wall of microcapsules. The preparation process of microcapsules was optimized. When the core / wall ratio was 1.5: 1: 1: 1, the stirring rate was about 400rpm, the surfactant was PVA and the concentration was 5%. When the evaporation temperature is 40 鈩，

本文編號：1394770