Synthesis And Application Of Efficient Chelating Dispersants Compatible With Surfactants

Since the chelating dispersant has both the ability to chelate metal ions and excellent dispersion properties,such as calcium and magnesium in hard water,it is widely used in various processes for printing and dyeing.Polycarboxylic acid additives are commonly used in the industry,represented by maleic anhydride-acrylic acid copolymers.Compared with chelating agents such as phosphates and EDTA,MALPOL copolymers not only have good chelating properties,but also have excellent solubilizing properties and colloidal properties,which can chelate metal ions in water while stably disperse the complexes.So it is very suitable for washing various kinds of fabrics after dyeing and printing.With excellent dispersion and suspension effects,the use of chelating dispersants in the dyeing process can make the fabric uniform in color.And the polymer is easily degraded and is an environmentally friendly polymer additive.However,currently the industry is facing a problem that needs to be solved.It is difficult to directly use Ma-C copolymer copolymers with surfactants?especially with polyoxyethylene ether non-ionic surfactants?,which greatly limits its application fields.In order to solve the industrial problems,this paper designs a polyoxyethylene ether group on the basis of the structure of the polypropylene-propylene copolymer to make it similar to the non-ionic surfactant structure,thereby improving the feasibility of compounding.The synthesis and application of polymers are mainly divided into the following four stages:1.Synthesis of Maleic Anhydride Polyethylene Glycol?MAG?;2.Synthesis of Copolymer MAG-AA;3.Combination of Copolymer and Surfactant;4.Copolymers in soaping applications.Following are the main experimental results.First,the experimental results showed that determining the n?maleic anhydride?:n?polyethylene glycol?=1.05:1,using PEG-400,controlling esterification temperature at 70? and the amount of p-toluenesulfonic acid at 3%,reacting time of 2.5 hours were the best Esterification conditions to synthesize MAG based on esterification rate.And the terification rate can reach about 90.5%.Second,after various factors discussed,obtained the copolymer MAG-AA polymerization process:using continuous dropping method,keeping ratio AA:MAG=25:5,controlling reaction temperature at about 80?.?NH4?₂S₂O₈ amount was 5%and isopropyl alcohol amount was 15%.Controlled 80 minutes of dropping and kept the temperature for 30 minutes.After adding dropwise,neutralized by adding sodium hydroxide solution until the temperature dropped to40?.The resulting polymer had a viscosity average molecular weight of about 2800,a chelated calcium value of about 560 mg/g,a dispersion value of about 320 mg/g,and the copolymer was named DB-3.At the same time,DB-3 can be successfully combined with anionic?such as SDS?,non-ionic surfactants?such as AEO-9,1815?and multi-component systems.At last,the soaping effect after active red and active cyan blue dyeing was used as an inspection index,the results showed that the optimal amount of DB-3 as a soaping agent was 2.5g/L,and after a small amount of surfactant?such as PVP?was compounded,soaping effect was effectively improved.