功能性纤维素膜材料的制备及其在缓控释农药中的应用

发布时间：2018-02-28 05:36

本文关键词： 纤维素功能化改性缓控释农药抗紫外荧光　出处：《中国农业大学》2017年博士论文　论文类型：学位论文

【摘要】：纤维素是自然界含量最为丰富的天然高分子材料,它具有良好的生物相容性和降解性,是一种非常具有潜力的石油化工产品的替代物。通过对纤维素进行改性,并根据实际需求,为农药量身打造功能性纤维素膜材料,可以进一步拓宽纤维素的应用范围。本论文制备出两种功能性纤维素材料(抗紫外纤维素膜材料和荧光性纤维素膜材料),并研究了两种膜材料在缓控释农药上的应用性能。(1)我们以LiCl/DMAc溶剂体系溶解微晶纤维素,以4,4'-二羟基苯甲酮(DHBP)为紫外线吸收剂,2,4-甲苯二异氰酸酯(TDI)为交联剂,制备出具有抗紫外性能的纤维素膜材料。通过红外和荧光谱图对该材料的化学结构进行确定,并对该膜材料的力学性能、热力学性能、抗紫外性能、亲疏水性进行探讨。结果表明,DHBP的引入,为纤维素添加了抗紫外的能力。通过增加交联剂的用量,可以提高纤维素材料的交联度,从而对膜的力学性能、热力学性能、抗紫外性能、亲疏水性能进行调节。(2)以上述具有抗紫外功能的改性纤维素膜为研究对象,通过紫外照射实验,对纤维素膜的紫外吸收能力进行表征。并在渗透扩散池中,对改性纤维素膜的控释性能进行表征。结果表明,改性后的纤维素膜材料表现出良好的紫外线保护能力,四种生物农药降解很少。根据太阳光照射下的四种生物农药的对比实验,可以大体估计改性纤维素膜材料可以对农药实现长效防护。通过渗透实验,改性纤维素膜的渗透速率可以根据交联度进行调控,交联度越大渗透越慢。(3)我们以荧光素和萘乙酸首先合成出荧光素二萘乙酸酯(FNE),并将其通过异佛尔酮二异氰酸酯(IPDI)接到乙基纤维素上,制备出具有荧光效应的纤维素膜材料。根据FNE的水解实验,发现其在中性条件下水解受萘乙酸浓度影响。通过对其力学性能、热力学性能进行测试,发现交联后的纤维素膜材料力学性能和耐热性比未交联的更好,FNE的加入对这些性质没有太大影响。(4)以上述荧光性纤维素膜材料为研究对象,通过对其化学控释、物理控释、低浓度指示作用进行了研究。结果表明,改性后的纤维素膜具有一定的化学释放萘乙酸的能力;萘乙酸的渗透速率与膜两侧的浓度差相关;当萘乙酸浓度过低时,改性纤维素膜的荧光开始恢复,并能通过肉眼进行观察。本论文的研究结果表明,纤维素膜材料通过改性后可以为农药量身打造合适的缓控释包膜。同时,改性纤维素膜材料在光引发、发光材料等方面,也具有良好的发展前景。由于缺乏相应的包膜技术,将纤维素膜材料进行进一步的实际应用,仍有待更多的研究。
[Abstract]:Cellulose is the most abundant natural polymer materials in nature, it has good biocompatibility and biological degradation, as a substitute for a potential oil chemical products. The cellulose was modified according to the actual demand for pesticides, tailored functional cellulose membrane materials, can further broaden the application the range of cellulose. This paper prepared two kinds of functional cellulose materials (UV resistant cellulose membrane materials and fluorescence of the cellulose membrane material), and study the two kinds of membrane materials in controlled release pesticide application performance. (1) we use LiCl/DMAc solvent system to dissolve cellulose, 4,4'- two hydroxy benzene ketone (DHBP) as a UV absorber, 2,4- toluene diisocyanate (TDI) as crosslinking agent, preparation of cellulose membrane material with anti UV properties. Through infrared and fluorescence spectra of chemical structure diagram of the material To determine the mechanical properties, the thermodynamic properties of membrane materials, anti UV properties, hydrophobicity were discussed. The results show that the introduction of DHBP, adding anti UV ability for cellulose. By increasing the amount of crosslinking agent, can improve the cellulose crosslinking degree, and mechanical properties of film the thermodynamic properties, anti UV properties, hydrophobic properties were adjusted. (2) the above has the function of anti ultraviolet modified cellulose membrane as the research object, through the ultraviolet irradiation experiments were characterized on cellulose membrane UV absorption capacity. And in the diffusion pool, the modified cellulose membrane controlled release properties were characterized. The results show that the modified cellulose membrane material after showing good UV protection capability, four kinds of biological pesticide degradation is few. Based on the contrast experiments of four kinds of biological pesticide under sunlight irradiation, can be modified to roughly estimate Cellulose membrane material can achieve long-term protection. Through the pesticide penetration test, penetration rate of modified cellulose membrane can be adjusted according to the degree of crosslinking crosslinking, the greater the degree of penetration is slower. (3) we first synthesized fluorescein fluorescein and NAA two naphthalene acetate (FNE), and then by isophorone diisocyanate (IPDI) from ethyl cellulose, preparation of cellulose membrane materials with fluorescent effect. According to the hydrolysis experiments FNE, found in the neutral condition by the NAA concentration. The effect of hydrolysis on the mechanical properties, thermodynamic performance test, found that the crosslinked cellulose membrane material mechanical properties and heat resistance than uncrosslinked better, the addition of FNE has little effect on these properties. (4) on the fluorescence of the cellulose membrane material as the research object, based on its chemical physical release, controlled release, indicating the effect in low concentration The study results showed that grafted cellulose membrane has certain ability of chemical release of NAA; concentration and membrane permeation rate on both sides of the difference of NAA; when NAA concentration is too low, the fluorescence modified cellulose membrane began to recover, and can be observed by the naked eye. The research results show that cellulose the membrane material of modified can be tailored for the pesticide controlled-release capsule suitable. At the same time, modified cellulose membrane material in photopolymerization, luminescent materials etc, also has good prospects for development. Due to the lack of appropriate coating technology, cellulose membrane materials for practical application further, still needs more research.

【学位授予单位】：中国农业大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TQ352.7;TQ450.4

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