嘧菌酯、噻虫嗪悬浮剂配方筛选与形成机制研究

发布时间：2018-04-21 03:33

本文选题：嘧菌酯 + 噻虫嗪　；参考：《中国农业大学》2016年博士论文

【摘要】：本论文通过利用x射线光电子能谱分析仪、傅里叶红外线光谱分析仪、扫描电子显微镜、Zeta电位仪、差热分析仪和流变仪等技术手段对25%嘧菌酯悬浮剂和21%噻虫嗪悬浮剂进行了细致综合的研究,为制备性能优良的悬浮剂提供了依据,其结论如下。对分散剂在嘧菌酯和噻虫嗪颗粒表面的吸附机理进行了研究。在298K、308K和318K的实验温度下,分散剂在嘧菌酯和噻虫嗪颗粒表面的吸附等温线模型均符合Lamgmuir模型,吸附动力学模型均高度符合准二级动力学模型。分散剂在嘧菌酯和噻虫嗪颗粒表面的热力学参数结果显示吸附均可自发进行,属于物理吸附,吸附过程均为熵增过程。钠离子浓度和pH均能影响分散剂在嘧菌酯和噻虫嗪颗粒表面的吸附。傅里叶红外光谱分析结果表明分散剂D-425,2700和2210与嘧菌酯之间、分散剂2700和2210与噻虫嗪之间均以范德华力为主结合在原药颗粒表面。Zeta电位结果显示分散剂D-425、2700和2210在嘧菌酯悬浮液中的最佳含量点分别为2.5%,2.0%和3.0%;分散剂2700和2210在噻虫嗪悬浮液中的最佳含量点均为3.0%。XPS结果显示嘧菌酯和噻虫嗪的C 1s和O 1s总峰在吸附分散剂后含量明显提高。分散剂在嘧菌酯和噻虫嗪颗粒表面的吸附层厚度随着温度的变化而变化,与吸附等温线宏观结果一致。在制作配方时,分散剂含量为最佳浓度时,吸附层厚度达到最大。热重数据结果显示分散剂/嘧菌酯体系在600℃以下为简单一步分解,分散剂/噻虫嗪体系在400℃以下为简单两步分解。通过FWO法分别对分散剂/嘧菌酯体系和分散剂/噻虫嗪体系进行热分解动力学研究,两个体系下的分散剂最佳含量均与Zeta和XPS结果相符,且在常规分散剂推荐含量2-3%的范围内,同一分散剂含量下不同转化率α的拟合公式平行性良好,表明FWO法能在实际应用中更好的指导分散剂在悬浮剂中含量的应用。分散剂/嘧菌酯和分散剂/噻虫嗪悬浮液的流变曲线均符合Hershel-Bulkley模型。在最佳分散剂用量时,体系的屈服值τH和黏度具有极小值,随着分散剂含量的增加,稠度指数K逐渐增大,流动特性指数n逐渐减小。分散剂/嘧菌酯和分散剂/噻虫嗪悬浮液体系的黏度均随时间有周期性振荡行为,在分散剂D-425、2700和2210最佳用量时,体系的振荡振幅较小,比较集中,稳定性较好。2700/噻虫嗪悬浮剂体系,分散剂含量在0-1.5%之间的流变振荡曲线剪切3min和10min有振幅,而当分散剂含量大于2%时振荡幅度逐渐减小,高浓度时几乎没有。2210/噻虫嗪悬浮剂体系振荡振幅较小。在298K、308K和318K下,随着温度的升高,分散剂/嘧菌酯和分散剂/噻虫嗪悬浮液体系的黏度逐渐降低；Hershel-Bulkley模型的三个代表参数屈服值τH、稠度指数k和流动特性指数n均随温度和pH的升高而变化;分散剂/嘧菌酯和分散剂/噻虫嗪悬浮液体系的流变振荡曲线的振荡频率和振幅均随着实验温度的升高发生了较大变化,温度越高振荡振幅越大,振荡曲线表现杂乱无序。利用精准量化的结果结合常规手段对悬浮剂的配方进行筛选,确定了在25%嘧菌酯悬浮剂中分散剂D-425、2700和2210的最佳用量分别为2.5%、2.0%和3.0%；在研发21%噻虫嗪悬浮剂过程中,发现仅2210能制备合格的悬浮剂,其最佳用量为3.0%。本论文制备的25%嘧菌酯悬浮剂和21%噻虫嗪悬浮剂理化性能指标良好,达到行业标准要求。
[Abstract]:By using X ray photoelectron spectroscopy analyzer, Fourier Infrared Spectroscopy Analyzer, scanning electron microscope, Zeta potentiometer, differential thermal analyzer and rheometer, the 25% thiazide suspension and 21% thiazimine suspension are studied in detail, which provides a basis for the preparation of excellent suspension agents. The adsorption mechanism of dispersant on the surface of azimetide and thiazimine particles was studied. At the temperature of 298K, 308K and 318K, the adsorption isotherm model of the dispersants on the surface of pyrazine and thiazimine particles conformed to the Lamgmuir model, and the average height of the adsorption kinetics model was in accordance with the quasi two stage kinetic model. The thermodynamic parameters of the surface of the ester and thiazimine particles show that the adsorption can be carried out spontaneously, which belongs to the physical adsorption, and the adsorption process is the entropy increase process. The concentration of sodium ion and pH can affect the adsorption of dispersants on the surface of pyrazine and thiazimine particles. The Fourier Infrared spectrum analysis indicates that the dispersant D-4252700 and 2210 are with pyrazine. Among the dispersants 2700 and 2210 and thiimazine, the optimal concentration of dispersant D-4252700 and 2210 in the suspension of azimthiazide was 2.5%, 2% and 3%, respectively, with the.Zeta potential on the surface of the particle on the particle surface of the original powder. The optimum content of dispersant 2700 and 2210 in the thiimazine suspension was 3.0%.XPS results. The total peak of C 1s and O 1s of azimetin and thiamazine increased obviously after the adsorption dispersant. The thickness of the adsorbed layer on the surface of the dispersant on the surface of pyrazine and thiazimine was changed with the temperature, which was in accordance with the macroscopical result of the adsorption isotherm. When the formulation was made, the thickness of the dispersant was the best. The thermal weight of the adsorbed layer was maximum. The data showed that the dispersant / pyrazine system was decomposed in a simple step below 600 C, and the dispersant / thiazine system was decomposed in a simple two step below 400 C. The thermal decomposition kinetics of dispersant / azoxpyrazine system and dispersant / thiazimine system were studied by FWO. The optimum content of dispersants under the two individual system were all with the content of the dispersant. The results of XPS are consistent, and in the range of recommended concentration of 2-3% for conventional dispersants, the fitting formula of different conversion rates under the same dispersant content is good, indicating that the FWO method can better guide the application of dispersant in the suspension agent in practical application. The rheological curves of dispersant / azoxpyrazine and dispersant / thiazine suspension are all in character. When the dosage of the best dispersant, the yield value H and viscosity of the system have minimal value. With the increase of the dispersant content, the consistency index K gradually increases and the flow characteristic index n gradually decreases. The viscosity of the dispersant / azoxpyrazine and the dispersant / thiazimine suspension system are all periodically oscillating with time, and dispersing with time. When the best dosage of agent D-4252700 and 2210, the oscillation amplitude of the system is smaller, more concentrated, the stability is better.2700/ thietazine suspension system, the rheological oscillation curve between 0-1.5% and 3min and 10min have amplitude, but when the dispersant content is more than 2%, the oscillation amplitude decreases gradually, and there is almost no.2210/ thiazine when the concentration is high. The oscillation amplitude of the suspension system is smaller. With the increase of temperature, the viscosity of the dispersant / azimetide / dispersant / thiimazine suspension system gradually decreases with the increase of 298K, 308K and 318K; the yield value H of the three representative parameters of the Hershel-Bulkley model, the consistency index K and the number n of the flow characteristics are all changed with the increase of temperature and pH; dispersant / azoxoxy. The oscillating frequency and amplitude of the rheological oscillation curve of the bacteria ester and the dispersant / thiazimine suspension system changed greatly with the increase of the experimental temperature. The higher the temperature, the greater the amplitude of the oscillation and the disorder of the oscillation curve. The formula of the suspension was screened by the result of precise quantification and the conventional means. The 25% azoxazin was determined. The optimum dosage of dispersant D-4252700 and 2210 was 2.5%, 2% and 3%, respectively. In the process of R & D 21% thiazimine suspension, only 2210 was found to be able to prepare qualified suspension agents. The optimum dosage was 3.0%., 25% azoxazin suspension and 21% thiazimine suspending agent had good physical and chemical properties, and reached the industry standard. Requirement.

【学位授予单位】：中国农业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TQ450.1

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