Peng Ruifen, Pang Yuxia, Qiu Xueqing, Qian Yong, Zhou Mingsong
School of Chemistry and Chemical Engineering, Guangdong Engineering Research Center for Green Fine Chemicals, South China University of Technology Guangzhou 510641 China.
School of Chemical Engineering and Light Industry, Guangdong University of Technology Guangzhou 510006 China.
RSC Adv. 2020 Apr 6;10(23):13830-13837. doi: 10.1039/c9ra10626j. eCollection 2020 Apr 1.
In the formulation of pesticide Suspension Concentrate (SC), some photosensitive pesticides are easily decomposed in the preparation. In this study, a hindered amine modified lignosulfonate (SL-Temp) with anti-photolysis function was synthesized using 4-amino-2,2,6,6-tetramethylpiperidine (Temp) and Sodium Lignosulfonate (SL) to solve this problem. The obtained SL-Temp was used as a dispersant to prepare 5% SC of avermectin, which shows good physical stability. The decomposition rate of the avermectin in SC after accelerating hot storage is 0%, which is much lower than 6.1% when SL was used as the dispersant. After being exposed to UV irradiation for 60 hours, the highest retention rate of avermectin is 87.1% when SL-Temp was used as the dispersant, which is much higher than 73.6% when SL was used as the dispersant, and also higher than 76.3% when a small molecule antioxidant (BHT) was added to the formulation. QCM-D studies revealed that the SL-Temp adsorption layer on avermectin particles can compete to absorb partial ultraviolet rays, hinder the penetration of ultraviolet light, and scavenge the free radicals produced by photooxidation, so as to protect avermectin from degradation.
在农药悬浮剂（SC）的配方中，一些光敏性农药在制剂过程中容易分解。在本研究中，使用4-氨基-2,2,6,6-四甲基哌啶（Temp）和木质素磺酸钠（SL）合成了具有抗光解功能的受阻胺改性木质素磺酸盐（SL-Temp），以解决这一问题。将所得的SL-Temp用作分散剂制备5%阿维菌素SC，其表现出良好的物理稳定性。加速热储存后，阿维菌素在SC中的分解率为0%，远低于以SL为分散剂时的6.1%。在紫外光照射60小时后，以SL-Temp为分散剂时阿维菌素的最高保留率为87.1%，远高于以SL为分散剂时的73.6%，也高于在制剂中添加小分子抗氧化剂（BHT）时的76.3%。石英晶体微天平耗散技术（QCM-D）研究表明，阿维菌素颗粒上的SL-Temp吸附层可以竞争吸收部分紫外线，阻碍紫外线的穿透，并清除光氧化产生的自由基，从而保护阿维菌素不被降解。
