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The amphiphilic hyperbranched polyesteramides (AHPAs) consisting of hydrophobic hyperbranched polyether cores and hydrophilic poly (ethyleneglycol) arms with urethane bonds in the molecular structure were synthesized by solution polymerization in chloroform using hexamethylene diisocyanate (HMDI) as a coupling agent. And their chemical structures were confirmed by FT-IR and and 13C NMR. Further, the AHPAs were applied to disperse organic pigments and their dispersibilities were investigated. The results showed that AHPAs had good dispersing effect on organic pigments. When the dosage of AHPA was 12% (on the weight of pigment), the dispersing effect of AHPA on phthalocyanine green was the best with the lowest relative settlement rate, viscosity and particle size. The dispersibilities of AHPA on organic pigments were phthalocyanine green > benzidine yellow G > pigment red F5R. AHPAs have the characteristics of high solubility, low viscosity, good rheological properties and no pollution and would be the ideal materials for using as the pigment dispersants.

To design and prepare targeted pesticides with environmentally responsive controlled release via compound and chemical modifications has shown great potential in creating novel pesticide formulations. Biological pesticide has spurred demand for efficient and effective delivery systems. In this work, an environmentally photoresponsive controlled release pesticide film was developed by encapsulating biological pesticide with spiropyran-grafted polyacrylic acid polymer as carrier and carboxymethyl chitosan as film-forming agent. Spiropyran-grafted polyacrylic acid polymer carrier had the characteristics of pH and light response. Under the pH response, pesticides were encapsulated. And under the light response, controlled release of pesticides was realized. A series of biological pesticides were encapsulated in the photoresponsive carrier and had high encapsulation rate. The photoresponsive polymer films could therefore be considered an efficient material for application in controlled release systems in agriculture.