【摘要】：細菌纖維素(BaacterialCellulose,簡稱BC)是一種由木醋桿菌發(fā)酵得到的纖維素材料,具有高持水性、生物可相容性、化學(xué)易修飾性和生物可降解性。近年來,由于其優(yōu)良的特性,BC在紡織、醫(yī)藥、食品、導(dǎo)電材料等領(lǐng)域具有良好的應(yīng)用前景。目前,BC生產(chǎn)面臨成本高、產(chǎn)量低的問題,同時其應(yīng)用也存在性能單一的問題。因此,如何尋找廉價易得的發(fā)酵原料及增產(chǎn)因子,如何控制BC的三維網(wǎng)狀結(jié)構(gòu)及開發(fā)BC基復(fù)合材料,是推進BC工業(yè)化應(yīng)用亟待解決的問題。在BC發(fā)酵生產(chǎn)方面。本文探究了以廢棄物豆粕為發(fā)酵原料生產(chǎn)BC的可行性。實驗結(jié)果表明,在硫酸濃度為1.5 wt%,料酸質(zhì)量比為1:4,水解時間為20 h,水解溫度為80℃的條件下預(yù)處理豆粕,得到的BC產(chǎn)量可達5.2 g/L,同時BC的氮源平均成本顯示出極具競爭力的成本優(yōu)勢。在BC結(jié)構(gòu)控制方面。首先,本文研究了添加氯化稀土(Rare Earth Chlorides,簡稱RECs)對木醋桿菌生長代謝及BC產(chǎn)量、形態(tài)結(jié)構(gòu)的影響。根據(jù)RECs對BC 產(chǎn)量的影響,有 8 種 RECs(Sccl3、Prc13、Gdcl3、Dyc13、Ec13r、Ybcl3、Yc13、Tbc13)具有明顯的促進作用;有 5 種RECs(Smcl3、Cecl3、Eucl3、Hoc13、Tmc13)具有明顯的抑制作用;有3種RECs(Lac13、Ndc13、Luc13)影響不大,其中,當(dāng)Lacl3的濃度由0 mg/L依次增加到20 mg/L和500 mg/L時,BC的結(jié)晶度由75.58%依次下降到68.11%和48.11%,孔隙率由97.3%依次下降到96.1%和97.1%。其次,研究了靜態(tài)發(fā)酵24h內(nèi),不同直流電場強度對木醋桿菌生長代謝及BC形態(tài)結(jié)構(gòu)的影響。結(jié)果發(fā)現(xiàn),在10 mA電場下的培養(yǎng)基中部,BC纖維呈定向排列,且纖維直徑由0 mA下的119.4 nm下降到74.7 nm。此外,BC的結(jié)晶度由0 mA的75.58%依次下降到培養(yǎng)基陰、陽極下的48.76%、58.59%,BC的孔隙率由97.3%分別下降到90.0%和92.8%。在BC復(fù)合材料制備及應(yīng)用方面。一方面,通過溶液浸漬法和交聯(lián)技術(shù)制備了 BC/ε-聚賴氨酸(BC/ε-PL)抗菌復(fù)合材料。研究發(fā)現(xiàn),BC/ε-PL中ε-PL的含量可通過ε-PL溶液的濃度進行調(diào)整,且隨著ε-PL濃度的提高,其對大腸桿菌和金黃色葡萄球菌的抗菌性也得到增強。其中,當(dāng)ε-PL溶液的濃度在0.75 wt%時,其在24 h內(nèi)對大腸桿菌的抑菌率為99.04%,對金黃色葡萄球菌的抑菌率為97.89%。另一方面,以BC為原料,通過溶液浸漬法、冷凍干燥和高溫?zé)峤庵苽淞说琢蚬矒诫s的細菌纖維素基碳納米纖維電極材料(N/P/S-PBC),并將其應(yīng)用于對稱型超級電容器。結(jié)果表明,在1.0A/g的電流密度下,N/P/S-PBC電極材料的比電容為255 F/g,且功率密度為489.45 W/kg時,能量密度可達8.48 Wh/kg。
[Abstract]:Bacterial cellulose (BaacterialCellulose, for short BC) is a cellulose material fermented by Acetobacter xylem. It has high water holding capacity, biocompatibility, chemically easy modification and biodegradability. In recent years, BC has a good application prospect in textile, medicine, food, conductive materials and other fields because of its excellent properties. At present, the production of BC is faced with the problems of high cost and low output, at the same time, its application also has the problem of single performance. Therefore, how to find cheap and easily available raw materials and production factors, how to control the three-dimensional network structure of BC and how to develop BC matrix composites are the urgent problems to be solved in the industrial application of BC. In BC fermentation production. In this paper, the feasibility of producing BC from waste soybean meal was studied. The results showed that when the concentration of sulfuric acid was 1.5 wt%, the mass ratio of feed to acid was 1: 4, the hydrolysis time was 20 h, and the hydrolysis temperature was 80 鈩，

本文編號：2245159