Modification Of Poly(m-phthaloyl-m-phenylenediamine)(PMIA) Polymer Membranes By Functional Organic Materials

In this paper,PULL@CPB/PM membrane with good separation and biocatalysis performance for protoplasmic beer was prepared based on the immobilized enzyme PULL@CPB,and the oil/water separation intelligent membrane modified by p H intelligent response coating was prepared.A novel pulluanase@chitosan porous beads/Poly（m-phthaloyl-m-phenylenediamine）（PULL@CPB/PM）membrane with good separation and biocatalysis properties was prepared by a self-adhesive method by introducing an immobilized enzyme（PULL@CPB）onto the PMIA membrane.The combination of PULL@CPB and PMIA could increase the one-step refining of protoplasmic beer as well as the ability of biocatalysis to lower the alcohol-to-ester ratio.The experimental results showed that the addition of PULL@CPB and the increase in the ratio of Et OH/water in the coagulation bath both increased the load of pullulanase on the membrane surface,while excessive addition decreased the activity of pullulanase.Under the amount of PULL@CPB is0.5 g·L^-1and the ratio of Et OH/water is 60%,the relative activity of pululanase in PULL@CPB modified PMIA membrane was the highest,which was 91.7%of the initial activity.The interception rates of protein and macromolecularβ-glucan were 92.2%and 87.3%,respectively,under the condition of beer flux(162.3 L·m^-2·h^-1).At the same time,the PULL@CPB/PM membrane has strong antibacterial performance and thus plays a role in extending the shelf life of beer.Compared with free pullulanase,the p H stability,thermal stability,organic solvent stability,and storing stability of immobilized pullulanase were significantly improved.The effects of PULL@CPB dosage and operating temperature on biocatalysis efficiency were discussed.The immobilized pullulanase activity on the membrane remained at 70.8%after 10 continuous uses.Therefore,the PMIA membrane is an excellent carrier of pullulanase,so its bioactive membrane has a wide range of prospects in medicine,food,and other fields.Intelligent membrane with reversible wettability is an ideal strategy for oil/water separation,but there are still limitations of the reality application of oil/water separation.This effort produced a distinctive,intelligent,p H-sensitive oil/water separation membrane.Modified silica（Si O₂-OTES）,low-budget titanic oxide（Ti O₂）,decanoic acid（DA）,pollution-free chitosan（CTS）,and Poly（m-phthaloyl-m-phenylenediamine）（PMIA）are selected to combine to form a superhydrophobic SO@TDC/PM membrane.The wettability of the modified membrane is reversible under the different effects of ammonia treatment and heat treatment.Also,the intelligent membrane is used to achieve controllable separation of oil/water mixtures,and to effectively separate various oil-in-water emulsions and water-in-oil emulsions before and after wettability conversion.In addition,the intelligent membrane has excellent self-cleaning ability,a high separation flux,and high separation efficiency.At the same time,the intelligent membrane itself has good organic solvent,storage,and mechanical stability.The results show that SO@TDC/PM membrane has good reversible wettability,which provides a broad prospect for the development of intelligent response materials with reversible wettability.Giving some properties of an immobilized enzyme to the PMIA membrane can improve the special application of the membrane,which has an inestimable exploration value in the process of beer preparation and separation.On the other hand,because the intelligent response coating material and PMIA membrane have a high degree of compatibility,they can be closely combined to fully improve the stability of the membrane material and enhance the hydrophobicity of the PMIA membrane.Therefore,the modification of PMIA membranes with functional materials has broad research prospects.