| Polyurethane has been widely used in various fields because of its high strength,wide hardness range and good wear resistance.In this paper,alcohol-soluble polyurethanes with different structures were synthesized,and explore their application properties in ink and pesticide preparations.The main results were as follows:1)synthesis of alcohol-soluble polyurethane: In this paper,a series of alcohol-soluble polyurethane were synthesized using toluene diisocyanate(TDI),polypropylene glycol and2,2-dimethylolpropionic acid(DMPA)as reactive monomers by chain extension reaction and pre-polymerization.Their structures were characterized by Fourier infrared spectroscopy(FTIR)and gel permeation chromatography(GPC).The results show that the synthesis of polyurethane was confirmed successfully,As the Mn of PPG increases gradually,the Mn of PU decreases first and then increases.2)Screening of ink formula: the control variable method was adopted to study the influence of the solvent type,the proportion of polyurethane binder and carbon black,the content of carbon black pigment,the type of dispersant and the type of wetting agent on the performance of ink in the ink preparation process.Through the optimization of the formula,the best ink formula was selected.As follows: carbon black pigment 12%,polyurethane binder 9.6%,dispersing agent Span-60 and wetting agent NNO 1%,solvent nitrogen methyl pyrrolidone supplement.3)The application of synthetic alcohol-soluble polyurethane in ink: The synthetic alcohol-soluble polyurethane was used as a linker in ink.The effects of different molecular weight PPG synthetic polyurethane on the viscosity,fineness,heat storage stability,printing ink suitability and rheological properties of ink were studied.The results showed that with increasing PPG molecular weight,the fineness and apparent viscosity of the ink increased first and then decrease.Especially,when polyurethane made by PPG 1500 as ink binder,the obtained ink demonstrated the best comprehensive performance,such as,apparent viscosity of 880 mpa·s,fineness of 5 μm,oil separation rate less than 5%,superior printability(adhesion of 93%,initial drying of 47 mm/30 s and gloss of 37)and excellent thixotropic behavior(the structure recovery rate of 94.47% at 15 s,respectively).4)synthol oil soluble polyurethane in pesticide suspension formulation(OD)application: the application of the alcohol soluble polyurethane as dispersant of synthesis in 35% atrazine.(OD,the determination of the content of the active components of five different OD,floating rate,particle size and thermal storage stability,and explored from the perspective of rheology stability of pesticide suspension agent.The results showed that the effective contents of the five samples all reached the standard,and the suspension rate increased first and then decreased with the increase of the relative molecular weight of PPG.The suspension rate,particle size and heat storage stability of the polyurethane synthesized by PPG3000 were the best when it was used as the dispersant.The response rate reached80.6% after 15 s.The thixotropy is the best. |
