Principle of water retaining agent

Introduction: superplasticizer uses super absorbent resin, which is a kind of functional polymer material with strong water absorption capacity So, the principle of water retaining agent? Come and have a look with you! When the water retaining agent is applied to the soil, with the regular changes of water absorption expansion and water loss shrinkage, the surrounding soil will become loose from compaction, and the pores will increase, so as to improve the permeability of the soil to a certain extent So, the principle of water retaining agent? Let's introduce the small edition of Baibai safety net! The water absorption principle of water retaining agent is the same as that of general saps It is formed by the interaction between the molecular chain expansion of polymer electrolyte caused by the same repulsion of amide group and / or carboxy group in water and the limitation of molecular chain expansion due to the crosslinking point Taking polyacrylamide as an example, the water retaining agent will have a large number of amide and carboxyl hydrophilic groups, which can absorb a large amount of water until the concentration difference disappears by using the osmotic pressure generated by the difference between the concentration of the internal ions and groups of the resin and the relevant components of the aqueous solution and the affinity between the polymer electrolyte and water It is the rubber elasticity that can control the water retention agent to achieve satisfactory water absorption The higher the crosslinking degree of molecular structure, the stronger the elasticity of rubber, and the balance point of elasticity and water absorption is its apparent water absorption capacity Due to the cross-linking of molecular structure, the water absorbed by molecular network can not be extruded by general physical methods to play a role of water conservation Therefore, the lower the crosslinking degree and the higher the water absorption ratio of the same polymer, the lower its water retention, stability and setting strength, and vice versa Therefore, in the world, the water retaining agent with long service life naturally needs high crosslinking degree, and does not pursue high water absorption ratio and speed Taking polyacrylamide as an example, its apparent ratio is not high, and the water absorption rate varies greatly according to the particle size The water retaining agent with high setting strength has a certain shape after water absorption and is not easy to disintegrate, which is conducive to soil permeability and good water absorption and drainage reversibility Because the water retaining agent is generally mixed into the underground 5 to 15 cm, the international now more emphasis on water absorption under pressure According to the particle size, the water absorption rate of polyacrylamide type is 150-300 The above is a small edition for you to introduce the principle of some of the content, I hope to help you oh! If you want to know more about food safety Please pay more attention to Baibai Security Internet bar! Editor in charge: Wang Xiujuan