High polymer material for resisting microbial film adhesion of filter bag and preparation method of high polymer material

Abstract

The invention relates to a high polymer material for resisting microbial film adhesion of a filter bag and a preparation method of the high polymer material, and belongs to the technical field of preparation of high polymer materials, organic functional groups such as carboxyl are introduced to the surface of SiO2 through a silane coupling agent to prepare a pretreated SiO2 filler, and then the pretreated SiO2 filler is used for enhancing PET to obtain SiO2-enhanced modified PET fibers. Finally, the fiber is soaked in protein subjected to acylation treatment, an amyloid protein layer is constructed on the surface of the fiber by reducing disulfide bonds, and the effect of preventing microbial adhesion is achieved. The anti-bioadhesion material prepared by the invention has the advantages of good mechanical properties and resistance to adhesion of microorganisms and algae.

Description

Technical Field

[0001] The present application relates to the technical field of polymer material preparation, and more specifically, to a polymer material for filter bags that resists microbial membrane adhesion and a preparation method thereof. Background Art

[0002] As a core component in the fields of industrial dust removal, water treatment, and medical protection, the surface anti-microbial adhesion performance of filter bags directly determines the service life and safety. The adhesion of microorganisms on the surface of the filter material and the formation of biofilms will lead to pore blockage, decreased air permeability, and increased risk of secondary pollution. Traditional filter materials are prone to become "hot spots" for microbial attachment due to their strong surface hydrophilicity and single charge distribution. Conventional antibacterial agents are prone to loss. The development of polymer materials with good anti-adhesion ability is of great significance to improving filtration efficiency, reducing maintenance costs, and ensuring public health safety.

[0003] Amyloid is a type of β-folded structure formed by misfolded proteins. However, the hydrophobic amino acids exposed on the surface of amyloid repel the hydration layer through hydrophobic interactions, destroying the wettability between microorganisms and materials. At the same time, the dense network structure formed by β-folds can physically block adhesion. At the same time, its adaptive conformation can resist shear force erosion, maintain long-term stability, and does not pollute the environment. Traditional amyloid needs to be obtained through strong acid hydrolysis or high-temperature denaturation, which leads to the loss of protein activity and is difficult to achieve uniform assembly on the fiber surface. In addition, the interfacial bonding with the matrix fiber is weak and easy to peel off during the filtration process, which limits its application in anti-adhesion materials.

[0004] Based on the above statements, the present application provides a polymer material for filter bags that resists microbial film adhesion and a preparation method thereof. Summary of the invention

[0005] In order to solve the problems raised in the background technology, the present application provides a polymer material for filter bags that resists microbial film adhesion and a preparation method thereof.

[0006] A method for preparing a polymer material for filter bags that resists microbial film adhesion comprises the following preparation steps:

[0007] S1, pre-treated SiO 2 The filler, terephthalic acid and ethylene glycol are mixed and reacted at 230-240°C for 2-3 hours to obtain an esterification product; then diethylene glycol and an antioxidant are added to the system, and the reaction is continued for 30-40 minutes to obtain a modified PET, which is then melt-extruded, spun and heat-set after drying to obtain a modified PET fiber;

[0008] S2. Treat the protein raw material with an acylating agent and then perform reduction modification to prepare a modified protein system; immerse the PET fiber obtained in step S1 in the modified protein system at a bath ratio of 1 g:10 mL, and then filter and dry to obtain a polymer material for filter bags that resist microbial film adhesion.

[0009] Furthermore, in step S1, the pre-treated SiO 2 The filler is specifically prepared by the following steps:

[0010] Nano-SiO 2 The powder was added to xylene solvent and stirred at room temperature for 10-15 minutes, then ultrasonically dispersed, and a silane coupling agent was added to the system. The system temperature was raised to 70-80 ° C and stirred, filtered, and extracted with acetone Soxhlet to remove impurities, and vacuum dried to constant weight to obtain pretreated SiO 2 filler.

[0011] Further preferably, in step S1, the pre-treated SiO 2 The filler is specifically prepared by the following steps:

[0012] Nano-SiO 2 The powder was added to a xylene solvent at a mass volume ratio of 1 g: (10-15) mL, stirred at 30-90 rpm for 10-15 minutes at room temperature, and then subjected to ultrasonic dispersion for 30-40 minutes. A silane coupling agent was then added to the system, the system temperature was raised to 70-80 ° C and stirred at 30-90 rpm for 4-5 hours, filtered and extracted with acetone Soxhlet for 24 hours to remove the unreacted coupling agent, and vacuum dried to constant weight to obtain pretreated SiO 2 filler.

[0013] In the above reaction process, silane coupling agent is used to bond SiO 2 Organic functional groups such as carboxyl groups were introduced into the surface to prepare pretreated SiO 2 Fillers are beneficial to enhance the chemical bonding ability with PET hydroxyl groups and regulate the surface charge environment to improve dispersibility. 2 The filler is chemically bonded to the PET hydroxyl group through functional groups such as silanol and carboxyl to form a nano-scale concave-convex structure, which improves the surface roughness and facilitates the subsequent anchoring of protein molecules.

[0014] Furthermore, nano-SiO 2 The mass ratio of powder to silane coupling agent is (5-10):(0.4-0.8).

[0015] Preferably, the silane coupling agent is KH570.

[0016] Further, in step S1, SiO is pretreated2 The mass ratio of filler, terephthalic acid, ethylene glycol, diethylene glycol and antioxidant is (0.4-2):(30-90):(0.8-1):(0.9-9):(0.12-1.8).

[0017] Furthermore, in step S1, the temperature of melt extrusion is 250-280°C, the screw speed is 50-150 rpm, and the back pressure is 5-15 MPa.

[0018] Further preferably, in step S1, the temperature of the melt extruder barrel zone 1 is 240-260°C, the temperature of the barrel zone 2 is 250-270°C, the barrel zone 3 is 260-280°C, the connector is 260-280°C, and the head zone 1 is 250-270°C.

[0019] Furthermore, in step S1, the specific operations of spinning and heat setting are:

[0020] The molten extruded melt is fed into the spinning assembly, extruded through the spinneret micropores to form a fine flow, and solidified by air cooling in the spinning tunnel. Subsequently, the solidified filaments are stretched and heat-set at a high speed of 1500-3000m / min. The heat-setting process is specifically set as follows: first relax at 240°C for 10 seconds, and then set at 230°C for 30 seconds to obtain modified PET fibers.

[0021] Furthermore, in step S2, the modified protein system is specifically prepared by the following steps:

[0022] S21, adding the protein raw material to deionized water, stirring at room temperature for 10-15 minutes, then adjusting the pH value of the system to 8.0-8.5, adding an acylation agent and raising the system temperature to 45-55° C., stirring and reacting for 1.5-3 hours, and maintaining the pH value of the system at 8.0-8.5 during the process; after the reaction, adjusting the pH value of the system to 4.0-4.5, centrifuging the system, collecting the precipitate, washing and drying to obtain the acylated protein;

[0023] S22. The acylated protein is partially reduced using ascorbic acid, and then completely reduced using a TCEP solution to obtain a modified protein system.

[0024] Further preferably, in step S2, the modified protein system is prepared by the following steps:

[0025] S21, adding the protein raw material to deionized water at a mass volume ratio of (6.5-8) g:100 mL, stirring at a rate of 30-90 rpm for 10-15 minutes at room temperature, then adjusting the pH value of the system to 8.0-8.5 with a 1 mol / L NaOH solution, adding an acylation agent and raising the system temperature to 45-55° C., stirring at a rate of 30-90 rpm for 1.5-3 hours, and maintaining the pH value of the system at 8.0-8.5 after the process; after the reaction, adjusting the pH value of the system to 4.0-4.5 with a 1 mol / L HCl solution, centrifuging the system at a rate of 4000-5000 rpm for 20-30 minutes, collecting the precipitate, washing the precipitate with deionized water until the pH value of the washing solution is neutral, and then drying to constant weight to obtain an acylated protein;

[0026] S22. The acylated protein obtained in step S21 is added to a 0.1 mol / L sodium bicarbonate buffer solution with a pH value of 8 at a mass volume ratio of (0.01-0.02) g:10 mL, and then a 0.1 mol / L ascorbic acid solution with a pH value of 8 is added at a volume ratio of 1:1, and the mixture is stirred at a rate of 100-300 rpm at room temperature and in the dark for 30-60 minutes. Subsequently, a 10 mM TCEP solution with a pH value of 7.5 is added to the system at a volume ratio of 1:1, and the mixture is stirred at a rate of 100-300 rpm at room temperature and in the dark for 30-60 minutes. After the system is dialyzed, a modified protein system is obtained.

[0027] In the above reaction process, the protein raw material is treated with an acylation agent. On the one hand, the acylation agent reacts with the ε-amino group on the protein, introduces a negatively charged group on the protein, interferes with the surface charge distribution of the protein, reduces the amino cationic effect, and promotes the combination of the protein component and the modified PET fiber. On the other hand, the acylated protein weakens the intermolecular electrostatic attraction, promotes the unfolding of the α-helix, and promotes the formation of the β-fold through the hydrogen bond network, which can better open the internal structure, expose the disulfide bonds originally buried inside, and allow the reducing agent to work better, promote the reduction of the disulfide bonds in the protein, and form an amyloid protein layer on the surface of the modified PET fiber.

[0028] Furthermore, the protein raw material is at least one of soy protein isolate, egg white protein and wheat gluten protein.

[0029] Furthermore, the acylating agent is succinic anhydride.

[0030] Furthermore, the specific operation of the heat setting is: first relax at 240° C. for 10 seconds, and then set at 230° C. for 30 seconds.

[0031] Furthermore, the mass ratio of the protein raw material to the acylating agent is 100:(5-12).

[0032] In summary, this application has the following beneficial effects:

[0033] In the technical solution of the present invention, a silane coupling agent is used to coat SiO 2 Organic functional groups such as carboxyl groups were introduced into the surface to prepare pretreated SiO 2 Fillers, which were subsequently used to reinforce PET, were obtained with SiO 2 Finally, the fiber was immersed in the acylated protein, and an amyloid protein layer was constructed on the fiber surface by reducing the disulfide bonds, thereby preventing microbial adhesion.

[0034] In the process, the protein raw material is treated with an acylation agent. On the one hand, the acylation agent reacts with the ε-amino group on the protein, introduces a negatively charged group on the protein, interferes with the surface charge distribution of the protein, reduces the amino cationic effect, and promotes the combination of the protein component with the modified PET fiber. On the other hand, the acylated protein weakens the intermolecular electrostatic attraction, promotes the unfolding of the α-helix, and promotes the formation of the β-fold through the hydrogen bond network, which can better open the internal structure, expose the disulfide bonds originally buried inside, so that the reducing agent can work better, promote the reduction of disulfide bonds in the protein, and form a self-assembled protein layer on the surface of the modified PET fiber. In the process, the process parameters are optimized to overcome the effect of modification on disulfide bond reduction and self-assembly. Specifically, the disulfide bonds are reduced by setting a step-by-step reduction method, first using a weak reducing agent for partial reduction, and then selectively reducing the non-essential disulfide bonds in the acylated protein by ascorbic acid, retaining the integrity of the intrachain disulfide bonds, avoiding excessive reduction leading to protein aggregation, and then using a reducing agent for complete reduction, further promoting the protein structure to β-fold transformation to form an amyloid protein layer. DETAILED DESCRIPTION

[0035] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] All reagents involved in the specific implementation methods of this application are chemically pure.

[0037] The silane coupling agent used was KH570.

[0038] The antioxidant used was antioxidant 1010.

[0039] Nano-SiO 2 The average particle size of the powder is 20 nm.

[0040] Wheat gluten protein: CAS No. 93384-22-6, purity 99%.

[0041] Soy protein isolate: CAS number 9010-10-0, purity 99%.

[0042] Example 1

[0043] A method for preparing a polymer material for filter bags that resists microbial film adhesion comprises the following preparation steps:

[0044] S1, pre-treated SiO 2 Filler, terephthalic acid and ethylene glycol were mixed and reacted at 230°C for 2 hours to obtain an esterification product; diethylene glycol and antioxidant were then added to the system, and the reaction was continued for 30 minutes to obtain modified PET, which was dried to constant weight and then melt-extruded. The temperature of the melt extruder barrel zone 1 was set to 240°C, the temperature of the barrel zone 2 was set to 250°C, the temperature of the barrel zone 3 was set to 260°C, the connector was set to 260°C, the head zone 1 was set to 250°C, the screw speed was set to 50rpm, and the back pressure was set to 5MPa; After spinning and heat setting, the molten extruded melt is fed into the spinning assembly and extruded through the micropores of the spinneret to form a fine flow. The spinneret hole diameter is 0.45 mm, and the aspect ratio is 8:1. The solidified filaments are air-cooled and solidified in the spinning tunnel. Subsequently, the solidified filaments are subjected to a spinning rate of 1000 m / min, 4 times post-stretching and heat setting treatment. The heat setting process is specifically set as follows: first relax at 240°C for 10 seconds, and then set at 230°C for 30 seconds to obtain modified PET fibers; pre-treat SiO 2 The mass ratio of filler, terephthalic acid, ethylene glycol, diethylene glycol and antioxidant is 0.4:30:0.8:0.9:0.12.

[0045] Wherein, the pre-treated SiO 2 The filler is specifically prepared by the following steps:

[0046] Nano-SiO 2 The powder was added to a xylene solvent at a mass volume ratio of 1 g:10 mL, stirred at 60 rpm for 15 minutes at room temperature, and then ultrasonically dispersed for 30 minutes. Then, a silane coupling agent was added to the system, the system temperature was raised to 70 ° C and stirred at 90 rpm for 4 hours, filtered and extracted with acetone Soxhlet for 24 hours to remove the unreacted coupling agent, and vacuum dried to constant weight to obtain pretreated SiO 2 Filler: Nano-SiO 2 The mass ratio of powder to silane coupling agent is 5:0.4.

[0047] S2, treating the protein raw material with an acylating agent, and then performing reduction modification to prepare a modified protein system; immersing the PET fiber obtained in step S1 in the modified protein system at a bath ratio of 1 g:10 mL, then filtering and drying at 50° C. to constant weight, thereby obtaining a polymer material for filter bags that resist microbial film adhesion;

[0048] Wherein, the modified protein system is prepared by the following steps:

[0049] S21, adding the protein raw material to deionized water at a mass volume ratio of 6.5g:100mL, stirring at 60rpm for 15 minutes at room temperature, then adjusting the pH value of the system to 8.0 with 1mol / L NaOH solution, adding an acylating agent and raising the system temperature to 45°C, stirring at 90rpm for 1.5 hours, and maintaining the pH value of the system at 8.0 after the process; after the reaction, adjusting the pH value of the system to 4.0 with 1mol / L HCl solution, centrifuging the system at 4000rpm for 20 minutes, collecting the precipitate, washing the precipitate with deionized water until the pH value of the washing solution is neutral, and then drying to constant weight to obtain acylated protein; the protein raw material is soy protein isolate, the acylating agent is succinic anhydride, and the mass ratio of the protein raw material to the acylating agent is 100:5;

[0050] S22. The acylated protein obtained in step S21 was added to a 0.1 mol / L sodium bicarbonate buffer solution with a mass volume ratio of 0.01 g: 10 mL, and then a 0.1 mol / L ascorbic acid solution with a pH value of 8 was added at a volume ratio of 1:1. The mixture was stirred at 100 rpm for 30 minutes at room temperature and in the dark. Then, a 10 mM TCEP solution with a pH value of 7.5 was added to the system at a volume ratio of 1:1. The mixture was stirred at 100 rpm for 30 minutes at room temperature and in the dark. The system was dialyzed with a molecular weight cutoff of 3 kDa to obtain a modified protein system.

[0051] Example 2

[0052] A method for preparing a polymer material for filter bags that resists microbial film adhesion comprises the following preparation steps:

[0053] S1, pre-treated SiO 2The filler, terephthalic acid and ethylene glycol were mixed and reacted at 235°C for 2.5 hours to obtain an esterification product; diethylene glycol and an antioxidant were then added to the system, and the reaction was continued for 35 minutes to obtain a modified PET, which was dried to constant weight and then melt-extruded. The temperature of the melt extruder barrel zone 1 was set to 250°C, the temperature of the barrel zone 2 was set to 260°C, the temperature of the barrel zone 3 was set to 270°C, the connector was set to 270°C, the head zone 1 was set to 260°C, the screw speed was set to 100rpm, and the back pressure was set to 10MPa. ; Then spinning and heat setting, the molten extruded melt is sent to the spinning assembly, extruded through the spinneret micropores to form a thin stream, the spinneret hole diameter is 0.45mm, the aspect ratio is 8:1, and air cooling and solidification is carried out in the spinning tunnel. Then the solidified filaments are subjected to 1000m / min spinning rate, 4 times post-stretching and heat setting treatment. The heat setting process is specifically set as: first relax at 240℃ for 10 seconds, and then set at 230℃ for 30 seconds to obtain modified PET fiber; pre-treat SiO 2 The mass ratio of filler, terephthalic acid, ethylene glycol, diethylene glycol and antioxidant is 1.2:60:0.9:5:0.5.

[0054] Wherein, the pre-treated SiO 2 The filler is specifically prepared by the following steps:

[0055] Nano-SiO 2 The powder was added to a xylene solvent at a mass volume ratio of 1 g:12 mL, stirred at 60 rpm for 15 minutes at room temperature, and then ultrasonically dispersed for 35 minutes. Then, a silane coupling agent was added to the system, the system temperature was raised to 75 ° C and stirred at 90 rpm for 4.5 hours, filtered and extracted with acetone Soxhlet for 24 hours to remove the unreacted coupling agent, and vacuum dried to constant weight to obtain pretreated SiO 2 Filler: Nano-SiO 2 The mass ratio of powder to silane coupling agent is 7:0.6.

[0056] S2, treating the protein raw material with an acylating agent, and then performing reduction modification to prepare a modified protein system; immersing the PET fiber obtained in step S1 in the modified protein system at a bath ratio of 1 g:10 mL, then filtering and drying at 50° C. to constant weight, thereby obtaining a polymer material for filter bags that resist microbial film adhesion;

[0057] Wherein, the modified protein system is prepared by the following steps:

[0058] S21, adding the protein raw material to deionized water at a mass volume ratio of 7.2g:100mL, stirring at 60rpm for 15 minutes at room temperature, then adjusting the pH value of the system to 8.2 with 1mol / L NaOH solution, adding an acylating agent and raising the system temperature to 50°C, stirring at 90rpm for 2 hours, and maintaining the pH value of the system at 8.2 after the process; after the reaction, adjusting the pH value of the system to 4.2 with 1mol / L HCl solution, centrifuging the system at 4500rpm for 25 minutes, collecting the precipitate, washing the precipitate with deionized water until the pH value of the washing solution is neutral, and then drying to constant weight to obtain acylated protein; the protein raw material is soy protein isolate, the acylating agent is succinic anhydride, and the mass ratio of the protein raw material to the acylating agent is 100:8;

[0059] S22. The acylated protein obtained in step S21 was added to a 0.1 mol / L sodium bicarbonate buffer solution with a pH value of 8 at a mass volume ratio of 0.015 g: 10 mL, and then a 0.1 mol / L ascorbic acid solution with a pH value of 8 was added at a volume ratio of 1:1, and the mixture was stirred at 200 rpm for 45 minutes at room temperature and in the dark. Subsequently, a 10 mM TCEP solution with a pH value of 7.5 was added to the system at a volume ratio of 1:1, and the mixture was stirred at 200 rpm for 45 minutes at room temperature and in the dark. The system was dialyzed with a molecular weight cutoff of 3 kDa to obtain a modified protein system.

[0060] Example 3

[0061] A method for preparing a polymer material for filter bags that resists microbial film adhesion comprises the following preparation steps:

[0062] S1, pre-treated SiO 2 The filler, terephthalic acid and ethylene glycol were mixed and reacted at 240°C for 3 hours to obtain an esterification product; then diethylene glycol and an antioxidant were added to the system, and the reaction was continued for 40 minutes to obtain a modified PET, which was dried to constant weight and then melt-extruded. The temperature of the melt extruder barrel zone 1 was set to 260°C, the temperature of the barrel zone 2 was set to 270°C, the temperature of the barrel zone 3 was set to 280°C, the connector was set to 280°C, the head zone 1 was set to 270°C, the screw speed was set to 150rpm, and the back pressure was set to 15MPa; Then, the melt was fed into the spinning assembly and extruded through the micropores of the spinneret to form a fine flow. The spinneret hole diameter was 0.45 mm, and the aspect ratio was 8:1. The solidified filaments were air-cooled and solidified in the spinning tunnel. Then, the solidified filaments were spun at a speed of 1000 m / min, stretched 4 times, and heat-set. The heat-setting process was specifically set as follows: first, relax at 240°C for 10 seconds, and then set at 230°C for 30 seconds to obtain the modified PET fiber. Pre-treat SiO 2The mass ratio of filler, terephthalic acid, ethylene glycol, diethylene glycol and antioxidant is 2:90:1:9:1.8.

[0063] Wherein, the pre-treated SiO 2 The filler is specifically prepared by the following steps:

[0064] Nano-SiO 2 The powder was added to a xylene solvent at a mass volume ratio of 1 g:15 mL, stirred at 60 rpm for 15 minutes at room temperature, and then ultrasonically dispersed for 40 minutes. Then, a silane coupling agent was added to the system, the system temperature was raised to 80 ° C and stirred at 90 rpm for 5 hours, filtered and extracted with acetone Soxhlet for 24 hours to remove the unreacted coupling agent, and vacuum dried to constant weight to obtain pretreated SiO 2 Filler: Nano-SiO 2 The mass ratio of powder to silane coupling agent is 10:0.8.

[0065] S2, treating the protein raw material with an acylating agent, and then performing reduction modification to prepare a modified protein system; immersing the PET fiber obtained in step S1 in the modified protein system at a bath ratio of 1 g:10 mL, then filtering and drying at 50° C. to constant weight, thereby obtaining a polymer material for filter bags that resist microbial film adhesion;

[0066] Wherein, the modified protein system is prepared by the following steps:

[0067] S21, adding the protein raw material to deionized water at a mass volume ratio of 8g:100mL, stirring at 60rpm for 15 minutes at room temperature, then adjusting the pH value of the system to 8.5 with 1mol / L NaOH solution, adding an acylating agent and raising the system temperature to 55°C, stirring at 90rpm for 3 hours, and maintaining the pH value of the system at 8.5 after the process; after the reaction, adjusting the pH value of the system to 4.5 with 1mol / L HCl solution, centrifuging the system at 5000rpm for 30 minutes, collecting the precipitate, washing the precipitate with deionized water until the pH value of the washing solution is neutral, and then drying to constant weight to obtain acylated protein; the protein raw material is soy protein isolate, the acylating agent is succinic anhydride, and the mass ratio of the protein raw material to the acylating agent is 100:12;

[0068] S22. The acylated protein obtained in step S21 was added to a 0.1 mol / L sodium bicarbonate buffer solution with a pH value of 8 at a mass volume ratio of 0.02 g: 10 mL, and then a 0.1 mol / L ascorbic acid solution with a pH value of 8 was added at a volume ratio of 1:1, and the mixture was stirred at 300 rpm for 60 minutes at room temperature and in the dark. Subsequently, a 10 mM TCEP solution with a pH value of 7.5 was added to the system at a volume ratio of 1:1, and the mixture was stirred at 300 rpm for 60 minutes at room temperature and in the dark. The system was dialyzed with a molecular weight cutoff of 3 kDa to obtain a modified protein system.

[0069] Comparative Example 1

[0070] The difference between this comparative example and Example 1 is that in step S1, the pre-treated SiO 2 In the process of preparing the powder, the amount of silane coupling agent is increased. 2 During the preparation of powder, nano-SiO 2 The mass ratio of powder to silane coupling agent is 5:0.8.

[0071] Comparative Example 2

[0072] The difference between this comparative example and Example 1 is that in step S1, the pre-treated SiO 2 In the process of preparing the powder, no silane coupling agent is used. 2 The powder is specifically prepared by the following steps:

[0073] Nano-SiO 2 The powder was added to xylene solvent at a mass volume ratio of 1 g:10 mL, stirred at 60 rpm for 15 minutes at room temperature, and then ultrasonically dispersed for 30 minutes. The system temperature was then raised to 70 °C and stirred at 30 rpm for 4 hours. After filtration, vacuum drying was performed to constant weight to obtain pretreated SiO 2 filler.

[0074] Comparative Example 3

[0075] The difference between this comparative example and Example 1 is that in this comparative example, the protein raw material is not treated with an acylating agent. Specifically, the modified protein system is prepared by the following steps:

[0076] The protein raw material was added to a 0.1 mol / L sodium bicarbonate buffer solution with a pH value of 8 at a mass volume ratio of 0.01 g:10 mL, and then a 0.1 mol / L ascorbic acid solution with a pH value of 8 was added at a volume ratio of 1:1, and the mixture was stirred at 100 rpm for 30 minutes at room temperature and in the dark. Subsequently, a 10 mM TCEP solution with a pH value of 7.5 was added to the system at a volume ratio of 1:1, and the mixture was stirred at 100 rpm for 30 minutes at room temperature and in the dark. The system was dialyzed at a molecular weight cutoff of 3 kDa to obtain a modified protein system.

[0077] Comparative Example 4

[0078] The difference between this comparative example and Example 1 is that in this comparative example, the acylated protein raw material is reduced in one step. Specifically, the modified protein system is prepared by the following steps:

[0079] S21, adding the protein raw material to deionized water at a mass volume ratio of 6.5g:100mL, stirring at 60rpm for 15 minutes at room temperature, then adjusting the pH value of the system to 8.0 with 1mol / L NaOH solution, adding an acylating agent and raising the system temperature to 45°C, stirring at 90rpm for 1.5 hours, and maintaining the pH value of the system at 8.0 after the process; after the reaction, adjusting the pH value of the system to 4.0 with 1mol / L HCl solution, centrifuging the system at 4000rpm for 20 minutes, collecting the precipitate, washing the precipitate with deionized water until the pH value of the washing solution is neutral, and then drying to constant weight to obtain acylated protein; the protein raw material is soy protein isolate, the acylating agent is succinic anhydride, and the mass ratio of the protein raw material to the acylating agent is 100:5;

[0080] S22. The acylated protein obtained in step S21 was added to 0.1 mol / L sodium bicarbonate buffer with a mass volume ratio of 0.01 g:20 mL, and then 10 mM TCEP solution with a pH value of 7.5 was added at a volume ratio of 1:1. The reaction was stirred at 100 rpm for 30 minutes at room temperature and in the dark. The system was dialyzed with a molecular weight cutoff of 3 kDa to obtain a modified protein system.

[0081] Performance Testing

[0082] The materials prepared in Examples 1-3 and Comparative Examples 1-4 of the present application were subjected to performance tests.

[0083] Mechanical property test: Use a universal material testing machine to test the material performance. Take the materials prepared in different groups of 40mm for testing. Set the fixture spacing to 20mm and the stretching rate to 100mm / min. Measure the tensile strength and elongation at break of different samples. Each group of samples is measured 5 times, and the average value is recorded.

[0084] The specific performance test results are shown in Table 1:

[0085] Table 1

[0086] Group Tensile strength(MPa) Elongation at break (%) Example 1 82.6 15.8 Example 2 84.2 16.3 Example 3 84.2 15.4 Comparative Example 1 82.3 16.0 Comparative Example 2 75.1 14.2 Comparative Example 3 78.4 15.3 Comparative Example 4 81.0 15.6

[0087] From the results shown in Table 1 above, we can see that:

[0088] The sample prepared in Example 2 has the best mechanical properties such as tensile strength and elongation at break among several groups of samples. From the results in Comparative Examples 1 and 2, it can be seen that the use of silane coupling agent can improve the SiO 2 Enhancement of fiber elongation at break by components. From the data of comparative example 3, it can be seen that acylated protein is also beneficial to improve the mechanical properties of the sample.

[0089] Anti-Biodadhesion Test:

[0090] The anti-bioadhesion properties of the samples in different groups were tested using the immersion method.

[0091] Microbial adhesion: 10 cm long samples were immersed in bacterial solutions of Escherichia coli (CMCC 44817) and Staphylococcus aureus (CMCC (B) 26003) respectively. After incubation for 12 and 24 hours, the samples were taken out and washed with PBS buffer for 30 seconds. The adhesion rate (%) of bacteria on the sample surface was determined by colony counting method. Adhesion rate = number of adhered bacteria / initial number of bacteria × 100%. Each group of samples was measured 5 times and the average value was recorded.

[0092] Microalgae adhesion: 0.2 g of Chlorella seeds and 0.5 g of glucose were mixed in 250 mL of deionized water, stirred evenly, and then 10 g of samples prepared in different groups were added. After culturing for 3 and 7 days, the samples were taken out, rinsed with running water for 1 minute, and then dried at 80°C to constant weight. The microalgae adhesion rate was determined, adhesion rate = sample growth mass after cultivation / initial weight × 100%. Each group of samples was measured 5 times, and the average value was recorded.

[0093] The specific test results are shown in Table 2 below.

[0094] Table 2

[0095]

[0096] From the results in Table 2, it can be seen that the several samples prepared in different groups are more sensitive to Staphylococcus aureus and the modified materials, and show better anti-adhesion effects. Several groups of samples show anti-adhesion effects on both microorganisms and algae. Among them, the samples in Example 2 have the best anti-adhesion effect on the three biomasses compared with the samples in other groups. It can also be observed that the adhesion of microorganisms has a certain time dependence. The microbial activity is strong and the adhesion rate is fast after 12 hours, but the subsequent adhesion is small, showing an effective barrier effect.

[0097] From the results in Table 1 and Table 2, it can be seen that the increase in the amount of silane coupling agent in Comparative Example 1 can improve the dispersion of the reinforcing material and increase the mechanical properties, but the surface roughness also decreases, resulting in a poorer loading effect on the protein, and the anti-adhesion effect of the formed protein film on microorganisms and microalgae decreases. The results in Comparative Example 2 also verify that not using a silane coupling agent leads to a decrease in the mechanical properties of the material and an increase in the surface roughness, but the assembly uniformity of the protein film decreases and the anti-adhesion effect decreases. The results in Comparative Examples 3 and 4 can verify that the acylation modification step and the step-by-step reduction treatment can reduce protein aggregation during the formation of the protein film, promote protein structure transformation, and improve the anti-adhesion effect of the protein film.

[0098] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0099] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A method for preparing a polymer material for filter bags that resists microbial film adhesion, characterized in that: The method comprises the following preparation steps: S1, mixing and reacting the pretreated SiO2 filler, terephthalic acid and ethylene glycol at 230-240°C for 2-3 hours to obtain an esterification product; then adding diethylene glycol and an antioxidant to the system, continuing the reaction for 30-40 minutes to obtain a modified PET, and then drying and melt-extruding, spinning and heat-setting to obtain a modified PET fiber; S2. Treat the protein raw material with an acylating agent and then perform reduction modification to prepare a modified protein system; immerse the PET fiber obtained in step S1 in the modified protein system, and then filter and dry to obtain a polymer material for filter bags that resists microbial film adhesion.

2. The method for preparing a polymer material for filter bag anti-microbial biofilm adhesion according to claim 1, characterized in that: In step S1, the pretreated SiO2 filler is specifically prepared by the following steps: Add nano-SiO2 powder into the solvent, stir at room temperature for 10-15 minutes, then disperse by ultrasonic, add silane coupling agent into the system, raise the system temperature to 70-80°C and stir, filter and remove impurities, and dry to obtain pretreated SiO2 filler.

3. The method for preparing a polymer material for filter bag anti-microbial biofilm adhesion according to claim 2, characterized in that: The mass ratio of nano-SiO2 powder to silane coupling agent is (5-10):(0.4-0.8).

4. The method for preparing a polymer material for filter bag anti-microbial biofilm adhesion according to claim 1, characterized in that: In step S1, the temperature of melt extrusion is 250-280°C, the screw speed is 50-150 rpm, and the back pressure is 5-15 MPa.

5. The method for preparing a polymer material for filter bag anti-microbial biofilm adhesion according to claim 1, characterized in that: In step S1, the temperature of melt extrusion is 250-280°C, the screw speed is 50-150 rpm, and the back pressure is 5-15 MPa.

6. The method for preparing a polymer material for filter bag anti-microbial biofilm adhesion according to claim 1, characterized in that: In step S2, the modified protein system is specifically prepared by the following steps: S21, adding the protein raw material to deionized water and stirring, then adjusting the pH value of the system to 8.0-8.5, adding an acylation agent and raising the system temperature to 45-55° C., stirring and reacting for 1.5-3 hours, and maintaining the pH value of the system at 8.0-8.5 during the process; after the reaction, adjusting the pH value of the system to 4.0-4.5, centrifuging the system, collecting the precipitate, washing and drying to obtain the acylated protein; S22. The acylated protein is partially reduced using ascorbic acid, and then completely reduced using a TCEP solution to obtain a modified protein system.

7. The method for preparing a polymer material for filter bag anti-microbial biofilm adhesion according to claim 6, characterized in that: The protein raw material is at least one of soy protein isolate, egg white protein and wheat gluten protein.

8. The method for preparing a polymer material for filter bag anti-microbial biofilm adhesion according to claim 6, characterized in that: The acylating agent is succinic anhydride.

9. The method for preparing a polymer material for filter bag that resists microbial film adhesion according to claim 1, characterized in that: The specific operation of the heat setting is: first relax at 240° C. for 10 seconds, and then set at 230° C. for 30 seconds.

10. A polymer material obtained by the method for preparing a polymer material for filter bag anti-microbial biofilm adhesion as claimed in any one of claims 1 to 9.

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