Synthesis Of Zwitterionic Polymer And Its Application In Textile Stiffening Processing

Because polyacrylate emulsion has the advantages of heat resistance,light resistance and aging resistance,it has been widely used in textile stiffening processing.However,the common polyacrylate stiffening finishing agents also have the disadvantages of low stiffness and high temperature stickiness;in addition,the presence of emulsifiers in conventional emulsion polymerization methods easily affects the film-forming properties of emulsions.In this project,two kinds of betaine zwitterionic monomers A and B,which were independently designed and synthesized,were used to prepare A and B betaine-type polyacrylate emulsion stiffening finishing agents using soap-free emulsion polymerization technology;they were applied to automobile safety The stiff finishing of the belt(high-strength polyester fabric)gives the fabric stiff and good heat-resistant stability.Take dimethylaminoethyl acrylate(DMAEA)and sodium chloroacetate as raw materials,N,N-dimethylglycine and propylene chloride as raw materials,respectively carry out quaternization reaction to synthesize betaine zwitterionic monomers A and B,The isopropanol hydrochloride solution was used as the titrant and bromophenol blue was used as the indicator to determine the quaternization conversion rate;the product structure was analyzed by infrared spectroscopy(FTIR).The experiment shows that the molar ratio of DMAEA to sodium chloroacetate is 1.00:1.05,the reaction temperature is 70 ?,the time is 8 hours,and the conversion rate can reach92.1%.The molar ratio of N,N-dimethylglycine to chloropropene is 1.0:1.1,and the reaction is at45? for 8 hours,and the conversion rate can reach 92.3%.Adopt soap-free emulsion polymerization method,use methyl methacrylate as hard monomer,butyl acrylate as soft monomer,experimentally synthesized betaine A or B as functional monomer,polyvinyl alcohol(PVA)as dispersant,Ammonium persulfate as initiator,sodium bicarbonate as buffer,soap-free emulsion polymerization in the water phase,two betaine-type polyacrylate stiffening agents were prepared.Experiments show that: keep the mass ratio of methyl methacrylate(MMA)to butyl acrylate(BA)at 12: 3 the amount of betaine A and BD are 3% to 4% of the total monomer mass,and the amount of PVA0588 is 0.75%,the amount of initiator is 0.8%,in a weakly alkaline aqueous system,the monomer conversion rate can reach 95.1% at 75? for 5h.Two different betaines,A and B,were used as functional monomers to prepare betaine polyacrylate stiffener emulsions with different addition amounts.The glass transition temperature of the emulsion after film formation was tested by DSC and DMA(Tg)and tensile strength(stiffness).The results show that the Tg and tensile strength of betaine B polyacrylate emulsion are higher than those of betaine A;when the amount of betaine A or B is 3% to 4%,the film baking temperature is 180?,When the time is 20 minutes,the film has higher rigidity,better mechanical properties,good heat resistance stability and good storage stability.Use A and B betaine polyacrylic acid emulsion as a stiffening finishing agent for the stiffening finishing of automobile seat belts,finishing through padding finishing process,the optimization finishing process of automobile seat belts: the amount of betaine A or B is 3 %?4%,the mass concentration of finishing agent is 400g/L,two dipping and two rolling,baking at 180?for 4 minutes.After finishing the fabric,the stiffness reaches the stiffening effect of the commercially available stiffener,and the stability of the hardness to the ambient temperature is higher than that of the commercially available stiffener.