Preparation Of Polyether Sulfone Anionic Endotoxin Filtration Membrane

Small doses of endotoxin can cause physiological and pathological reactions,manifested as the body fever,white blood cell reaction,glucose metabolism disorders,vasomotor disorder,etc.,even can lead to death.Endotoxin can exist in everywhere we can touch,so it's urge to us to find an effective strategy to remove endotoxin especially in the medical field.This method must can be produced in a large quantities.In this paper,a large number of studies have been conducted on the elimination of endotoxin at home and abroad,and a method for efficiently removing endotoxin has been explored.The method of specifically removing endotoxin-anion exchange and non-specific endotoxin Filter can be combined.This product is called polyether sulfone anionic endotoxin filter membrane.In this paper,we use the polyether sulfone materials which are popular and high performance to modify.In order to obtain the anion exchange membrane we need to add the most active quaternary ammonium groups into the polyether sulfone.Firstly,we need to introduce the active group chloromethyl group?-CH₂Cl?to the side chain of the polyether sulfone.That is called the chloromethylation reaction.1,4-dichloromethoxybutane was be chose as the chloromethylation reagent because of the high reactivity,short reaction time and environment-friendly.The effects of reaction time,reaction temperature and amount of chloromethylating agent on the degree of chloromethylation were evaluated.The polyether sulfone with the highest degree of chloromethylation was selected as the reactant to carry out polyether sulfone quaternization reaction.The quaternization reaction of the polyether sulfone is a reaction in which the quaternary ammonium group is introduced into the polyether sulfone by changing the tertiary ammonium salt R3 N and the haloalkyl R-X to the quaternary ammonium salt [R₄N +] [X-].A high degree of quaternization was selected as a quaternary ammonium reagent,and a mixture of homogeneous and heterogeneous methods was used to find out how to obtain a polyether sulfone with a higher degree of quaternization and how to obtain a polyether with a positive charge sulfone.And finally the quaternized polyethersulfone membrane was prepared by the formula of industrial filmIn this paper,the three-factor three-level orthogonal test was designed to evaluate the chloromethylation degree of chloromethylated with the reaction time,the reaction temperature and the reaction amount ofchloromethylated reagent.Through nuclear magnetic characterization,it was found that the degree of chloromethylation increased with the increasing of reaction temperature,and the optimum reaction temperature was 90 degrees.With the increase of the amount of chloromethylating agent,the degree of chloromethylation was be increased,and the optimum amount of reagents was 14.4g.With the increasing of reaction time,the reaction rate was changed from fast to slow,and the optimum reaction time was 6h.With the highest degree of chloromethylation,was used as the reactant of quaternization reaction and trimethylamine as quaternized reagent,the results showed that quaternized polyether sulfone could be successfully prepared.The zeta potential shows that the surface of the quaternized polyether sulfone has a positive charge,which is the characteristic of the quaternary ammonium group grafted on the polyether sulfone.The infrared spectrum shows the characteristic peaks of the polyether sulfone with the quaternary ammonium group.Finally,we also use 0.25 EU / ml sensitivity of the limulus reagent for endotoxin filter test,according to the principle that the limulus reagent reacts with endotoxin reaction to produce gels,the results were observed by turning the test tube to observe the shape of the gel.The shape of the gel was observed by reversing the test tube to determine the result.The filtrate did not render the limulus reagent in a gel state,this phenomenon showed that the polyether sulfone anion filtration membrane was able to remove endotoxin.In summary,the preparation of quaternized polyether sulfone was successfully prepared by using1,4-dichlorobenzyloxybutane as the chloromethylation reagent,with the temperature of 90 degrees,the reaction time of 6h,the chloromethylating agent of 14.4g.The quaternized polyether sulfone was successfully prepared by using Trimethylamine as quaternization reagent.The film was able to successfully remove trimethylamine.