Preparation of Polymer Membrane with Molecular Recognition Function by Molecular Replication

Preparation of Polymeric Membrane with Molecular Recognition Function by Molecular Replication Method WANG Hongying, LU Rufeng, CAO Shaokui, SUN Hong Department of Materials Engineering, Zhengzhou University, Zhengzhou, 450052, China College of Chemistry and Chemical Engineering, Zhengzhou University, Zhengzhou, 450052, China, contains film-forming backbone residues and functional residues. The acrylonitrile-acrylic copolymer was used as a membrane material, and a polymer membrane with molecular recognition function was prepared by phase inversion precipitation method. , D, 1 and 1 test results showed that there was a hydrogen bonding interaction between the template molecule and the functional residues in the film of the polymer film prepared. A large amount of polar acetic acid aqueous solution can extract the template molecules in the membrane. The solution and the 3,7 methylxanthine caffeine with a similar structure to the template molecule, 0, the matrix of the solution through the experimental results into the membrane structure, the amount of molecules is much greater than 0 molecules, this brightly prepared polymer membrane has 10 molecules The identification function experimental results also show that the amount of 10 molecules entering the membrane structure is proportional to the amount of template molecules added in the wipe solution during film formation by phase inversion precipitation.

The above molecular replicating macromolecule materials are mostly used in the form of a resin and a stationary phase, and in the preparation of a polymer membrane closely related to a macromolecular material, the application of a molecular replication method has rarely been reported. Based on the above situation, we combined the molecular replication method with the phase-conversion film-making method. In the phase-conversion film-forming process, a molecular hole is formed in the film, and a 5-film, functional, wide film is prepared. Take it. , Xian; Fruit 1. This study selected cooking utensils with film-forming propylene as the ossification 001 called 1 can be hydrogenated with acrylic acid as the functional group. Synthetic copolymer, he, from the dematerialized structure to the drug 3 methyl xanthine base. Claw 0, Structure 2 is a template molecule, and a polymer film having a molecular recognition function was prepared. In this paper, we report the characteristics of the polymer film with the molecular recognition function of 0, and the molecular knowledge of the film in different solute solutions was investigated by phase inversion method. The structure of the film is as follows: The synthetic Ubbelohde viscometer measured the viscosity of the copolymer was 2125,3 also according to the literature, the molecular weight of the copolymer was approximately 70 1.2 Molecular replication membrane preparation The molecular replication membrane was prepared by a phase inversion process.

The copolymer was made from 0 to 0 wiper solution, in which the concentration of the copolymer was fixed at 10; the concentration of template molecule D in the solution was 0,417 and the measured value of D was 0. 47. Water is a non-solvent at the time of coagulation of the copolymer, that is, a coagulation liquid. After the film was formed, it was eluted with a large amount of water and an acid solution of the boat. In order to remove the film residue and the solvent and helium, 1.3 film properties were measured and the solute permeation test was performed. The structure of the replicated film was identified by scanning electron microscopy. 733. Infrared spectroscopic measurement of the film was performed using a film method. Membrane evaluation with dextran in the range 04, 2106 Germany, 3 using a small cup type ultrafiltration device 18,51 type, the United States such as mixing PANcoAADMSOTHO film scraping liquid, scraping the film on the support, placed in the water and curing the scraping film The liquid phase was changed to water to remove 0130, and the acetic acid solution was used to wash and remove the butadiene. The above apparatus was also used. And, 耄, 苤 耐 耐, 椤T, Hantun, brown crumbs, barrels, solute concentration only 0 It. Wooden Cao Da, column Ding 800880.18 detector. 270 into the hall analysis.

Journal of Peking University Journal of Natural Science 2 Results and discussion 2.1 Hydrogen bonding of functional residues in dioxins and heart human membranes In order to confirm the preparation, the functional residues in the membrane were hydrogen-bonded to 10 molecules. Presence, the infrared spectrum of the film was measured and the spectra of the film 1 before washing 1 and after washing with the acetic acid solution were compared. 2 is an infrared spectrum of a polymer film prepared using a wipe solution containing 41710. The CN movement was observed at the 2242 cm1 of the spectra of the membrane 1 and the membrane M2. The authors noticed that the stretching vibration at 1=0 base is about 6 higher than 2, and this slight difference can be presumed to be due to the stretching vibration of two wide 0 bases between the membranes.

The mode of hydrogen bonding of 10 molecules to the 0-thiol group in the film is as follows: a 3-mer form of the 0-group, and a 01-form of the 1-monomer form is well-known. In a carboxylic acid, a radical has a strong hydrogen bond between molecules, often In the form of a polymer, its stretching vibration occurs in the range of 3300, 2500, 1 . On the other hand, the vibration of the free thiol group is near 3,500,1. Therefore, two absorption peaks at 3 216 cm 1 and 3522 cm 1 in 2 can be attributed to the stretching vibrations of the polymer and free OH groups, respectively.

It can be clearly seen from the infrared spectrum that the absorption of free OH groups located at 3522Cm1 of the membrane M1 not washed with the acetic acid solution is greater than the absorption of OH groups of the polymer of 3216Cm1; the membrane M2 after washing with the acetic acid solution is located Absorption of the free radicals of the 3522 coffee 1 is less than the absorption of the 0 base of the polymer of the 3216 coffee 1 . The OH groups in this enamel membrane are mostly present in the free state, while the OH groups in the membrane M2 are mostly present as mers. The causes of these structures can be explained with reference to FIG. 3. For the film 42, since the three molecules of the masking agent were removed, a small molecule 2.2 was formed in the film, and a SEM photograph of the characteristic cross section of the polymer film was formed. It can be observed from the photograph that all membranes have a typical ultrafiltration membrane structure. When the addition amount of THO is 0.5, there is no obvious effect on the formation of the membrane structure. However, with the increase of the concentration of dibutyl trioxide in the coating solution up to 2.5, the thickness of the dense layer of the membrane located in the upper part of the fingerprint zone is significantly increased.

Flow seen from the film, wiped film occurs in a liquid non-solvent water and solvent exchange, DMSO is miscible with water into the aqueous phase, insoluble in water, where the copolymer undergoes a phase transformation from the solid phase into the liquid phase, in which process Instantaneous completion, and from the former, the precipitation of human copolymer into a polymer film morphology structure 8. The thickness of the dense layer of the film is mainly determined by the size of the coagulation ability of the film-forming backbone in the copolymer. Due to the interaction of the 10 residues, the molecular ratio of the functional residues in the 10 and the copolymer was reduced when the AN formed the backbone 215, and 70 all interacted with the functional residues, which allowed the AN to form the backbone. lowest freezing capacity, the thickness of the dense layer of the resulting film up to 4. Since the electrode 10 is a molecular weight dextran molecules 10, can promote the phase inversion process is completed, the result was a polymer film having a thinner dense layer 4.

curve. Defining the molecular weight cut-off of the membrane is a rejection of 9 when the molecular weight of the glucan is 9 and the molecular weight of the resulting membrane is between 4.8105 and 5.8106. The D, molecular weight of 180.2, which depends only on the retention characteristics of the membrane, can not prevent the D10 molecules through.

2.31 Membrane D, 3 Molecular Recognition and Selectivity In order to investigate the molecular recognition properties of the membrane, a matrix-through test of the solution was performed using a small cup-type ultrafiltration device.

The determination of the solute concentration in the solution through the liquid was performed using 410, and based on the volume of the permeate, the amount of 10 molecules bound to the membrane due to the hydrogen bonding was calculated. The unit gives the results of various membrane experiments made with wiper fluids with template molecular contents of 0, 0.5, 1.5, 2.5, and 4.7, in units of moles per gram of film, in units of 1.6. For ease of comparison, the addition of AN homopolymer PAN was also given at 6 and equilibrium was reached at a given time. At this point, the total amount of MTHO does not change anymore; the MTH0 of various membranes increases with the increase of the amount of 10 molecules added in the filming solution during film formation.

Through the results of the experiment, the existence of 10 holes in the film was confirmed. And the number of small holes formed in the film is proportional to the amount of 70 molecules added in the film.

At the same time as 10 solutions were passed through the experiment, 3,7-methylxanthine caffeine with a similar structure to 70, a permeation experiment of a solution of the structure 2 of CAF was also performed, and 7 out of the same method was used, containing 0,215 The content of dimethoate 0 in the film-squeegee solution is 0; 0.5, and the amount of binding in the dip-film solution is 0, 0.5 in the filming solution with the change of the permeation time. Valley's, Marriage's, Membrane's, and Modular's experimental fruits. Si Comparative D 0; if the broken line 7, D 0 through 4.7 membrane experimental data, the number of moles of molecules bound to the membrane is far less than 0 0.

0 is formed by replacing the 7-position nitrogen atom of 0 with 013, and the disappearance of the atom causes the disappearance of hydrogen bonding between the molecule and the OH group in the film. As a result, the molecule at 0 cannot be recognized by the film and enters the film. The results of 7 proved that the prepared, from, into the film has a good selectivity, and at the same time, the progress has proved that the template molecule and the 0-based bond in the film are treated.

Formula 1 was used to quantitatively calculate the selectivity factor for the 0 and 0 of the film. The results are listed in 1. The value is clear, and the film prepared by the wiper solution of 4.7 丁0 has good selectivity to zero.

3 Conclusions Addition of the scraping liquid as a template, the film was formed by a rice phase transformation method, and after washing with an acetic acid solution, a polymer film with a molecular recognition function of 10 molecules was prepared. Infrared spectroscopy confirmed that the polymer film interacted with the template molecule to generate hydrogen bonds, and that the solute transmission test results showed that the prepared film had a higher selectivity for D. The 10 template molecules in solution can be identified, but for similar structures, extremely low selectivity appears.

The reference film descriptions 1 and 30 have units of 10 and 0 moles per gram of film, respectively.