基本原理
Basic Principles
① 空间位阻效应
(1) steric hindrance effect
高分子化合物具有较大的分子量，高分子链在介质中充分伸展形成几纳米到几十纳米厚的吸附层，从而产生空间位阻效应。
Polymer compounds have large molecular weight. Polymer chains extend sufficiently in the medium to form adsorption layers several nanometers to tens of nanometers thick, resulting in steric hindrance effect.
② 静电排斥理论
(2) Electrostatic repulsion theory
分散剂通过离子键、共价键、氢键及范德华力等相互作用在农药颗粒界面吸附时，亲水基使颗粒带上负电荷，在分散粒子周围形成扩散双电层，产生电动电势即Zeta电势。当两个带有相同电荷的分散相离子相互靠近时，扩散双电层重叠而产生的静电排斥迫使带电的分散相离子相互分开，阻止了其合并，使悬浮体系保持其分散稳定性。
When the dispersant adsorbs at the interface of pesticide particles through the interaction of ionic bond, covalent bond, hydrogen bond and van der Waals force, hydrophilic groups bring negative charges to the particles and form a diffusion double layer around the dispersed particles, which generates the electromotive force, i.e. Zeta potential. When two dispersed phase ions with the same charge are close to each other, the electrostatic repulsion caused by the overlap of the diffusion double layer forces the charged dispersed phase ions to separate from each other, which prevents their merging and keeps the suspension system stable.
③ 溶剂化链作用
(3) Solvation chain action
通过其疏水基对农药颗粒产生齿形吸附，亲水基朝水定向排列与水分子可以形成氢键，从而形成亲水性立体保护膜，该保护膜也进一步保证了离子的分散稳定性。
The hydrophobic group adsorbs the pesticide particles in tooth shape, and the hydrophilic group aligns with water molecules to form hydrogen bonds, thus forming a hydrophilic three-dimensional protective film, which further guarantees the dispersion stability of ions.