A permanently antimicrobial long carbon chain nylon polymer, its method of preparation and articles

Abstract

The present application relates to the technical field of functional nylon preparation, in particular to a permanent antibacterial long carbon chain nylon polymer, a preparation method thereof and a product thereof. The permanent antibacterial long carbon chain nylon polymer is prepared by using a nylon 1212 prepolymer with amino groups at both ends as a macromolecular initiator, initiating ring-opening copolymerization of a Boc-protected lysine internal anhydride monomer, and then performing post-treatment such as acidification deprotection or alkyl substitution reaction. Tests show that the permanent antibacterial long carbon chain nylon polymer has broad-spectrum and long-acting antibacterial effect, the initial antibacterial property reaches more than 95%, and the antibacterial durability and stability are good, the antibacterial property after soaking for one month still remains more than 95%. In addition, the physical and mechanical properties are excellent, and the permanent antibacterial long carbon chain nylon polymer can be used as a public health material and applied in various fields such as medical devices, textiles, packaging materials and various panels; and the preparation process is simple, the conditions are mild, and the large-scale production is easy to realize.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of functional nylon preparation, and particularly relates to a permanent antibacterial long carbon chain nylon polymer, a preparation method thereof and a product. BACKGROUND

[0002] Long carbon chain polyamide (LCPA) generally refers to a unit methylene length in a chain segment of 10 or more, such as PA10, PA12, PA1012, PA1212, etc. Compared with short carbon chain polyamides represented by PA6 and PA66, the longer freely stretchable methylene long chain in the structure exhibits more excellent physical and mechanical properties such as flexibility and characteristics such as low temperature resistance, low density and lower water absorption. Among the commercialized LCPA, the nylon 1212 series and its elastomer materials are the most common, and are often used to replace silicone rubber and fluororubber, and are widely used in medical packaging, liquid medicine and blood storage and infusion, and various catheters and medical equipment accessories. However, bacteria are easy to adhere, breed and form biofilms on the surface of materials or devices, which may cause bacterial infection,

[0003] Some antibacterial nylon materials are provided in the prior art, which can be mainly divided into two categories of composite reinforced nylon and permanent antibacterial nylon, and are mainly concentrated in nylon 6 and its related composites. For the composite reinforced nylon, such as CN201310003682.7, CN201410061129.3, CN202310429959.6, etc., the antibacterial performance is mainly derived from the addition of inorganic silver and other small molecule antibacterial agents. However, the antibacterial effect of the antibacterial material provided by these schemes is poor, and the small molecule antibacterial agent added is easy to precipitate, which not only leads to a decrease in antibacterial performance, but also causes potential safety problems such as cytotoxicity.

[0004] For the permanent antibacterial nylon, such as CN202310695750.4, CN202110604927.6, CN202110960422.3, CN202210355249.9, etc., the antibacterial performance is realized by introducing antibacterial units such as Schiff base, guanidino group and imidazolium salt into the nylon 6 polymer structure. However, the water absorption of nylon 6 material itself is high, and the product is easy to absorb moisture in the environment, which provides a good breeding place for bacteria and fungi, and is not suitable for application in packaging, panels, medical devices and other fields. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to provide a permanent antibacterial long carbon chain nylon polymer, a preparation method thereof and a product. The long carbon chain nylon polymer provided by the present application not only has high permanent antibacterial performance, but also has good mechanical properties.

[0006] This invention provides a permanent antibacterial long-chain nylon polymer, comprising a diamino-terminated nylon 1212 prepolymer unit and a lysine anhydride monomer unit;

[0007] The diamino-terminated nylon 1212 prepolymer unit has the structure of formula Ia;

[0008]

[0009] The number of repetitions of the chain segment to which it belongs;

[0010] The lysine anhydride monomer unit has a structure of formula Ib.

[0011]

[0012] Wherein, R1, R2, and R3 are independently hydrogen, substituted or unsubstituted C1-C6 groups. 16 One of the alkyl groups; or, R1, R2 and R3 and the N attached to them together constitute a substituted or unsubstituted guanidine group;

[0013] The m represents the number of repetitions of the chain segment to which it belongs.

[0014] In the permanent antibacterial long-chain nylon polymer of the present invention, the sum of n and m is an integer from 10 to 500, preferably an integer from 20 to 400, and more preferably an integer from 20 to 300. The permanent antibacterial long-chain nylon polymer of the present invention is a copolymer block polymer with a weight-average molecular weight of 2000 g / mol to 40000 g / mol.

[0015] The bisamine-terminated nylon 1212 prepolymer unit of this invention is derived from bisamine-terminated nylon 1212 prepolymer monomers with a weight-average molecular weight of 600 g / mol to 20000 g / mol. Considering its solubility and initiation activity, it is preferably derived from bisamine-terminated nylon 1212 prepolymer monomers with a weight-average molecular weight of 600 g / mol to 4000 g / mol. The bisamine-terminated nylon 1212 prepolymer monomer is also known as a bisamine-terminated nylon 1212 macromolecular initiator, which has the structure of formula II.

[0016]

[0017] The term n is the same as described above and will not be repeated here.

[0018] The lysine anhydride monomer unit of this invention is derived from lysine anhydride monomers. In some embodiments of this invention, the lysine anhydride monomer is derived from compounds having the structure of Formula III:

[0019]

[0020] Wherein, R is a protecting group. In some embodiments of the present invention, the protecting group is selected from tert-butoxycarbonyl (Boc), 9-fluorenylmethoxycarbonyl (Fmoc), or p-methoxybenzyl (PMB).

[0021] In the lysine anhydride monomer unit of the present invention, R1, R2, and R3 are independently selected from hydrogen, substituted, or unsubstituted C1-C6 groups. 16 One of the alkyl groups; or, R1, R2, and R3, together with the N attached to them, constitute a substituted or unsubstituted guanidine group. In some embodiments of the invention, R1, R2, and R3 are independently selected from hydrogen, substituted or unsubstituted C1-C1 groups. 16 Straight-chain alkyl or C1-C 16 One of the branched alkyl groups. In other embodiments of the invention, R1, R2 and R3 are independently selected from one of hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-hexyl, n-heptyl or n-octyl.

[0022] The molar percentage of the bisamino-terminated nylon 1212 prepolymer unit in the polymer is 0.1 to 0.8; the molar percentage of the lysine anhydride monomer unit in the polymer is 0.2 to 0.9; and the sum of the molar percentages of the bisamino-terminated nylon 1212 prepolymer unit and the lysine anhydride monomer unit in the polymer is 1.

[0023] Preferably, the molar percentage of the bisamino-terminated nylon 1212 prepolymer unit in the polymer is 0.15 to 0.6; and the molar percentage of the lysine anhydride monomer unit in the polymer is 0.4 to 0.85.

[0024] More preferably, the molar percentage of the bisamino-terminated nylon 1212 prepolymer unit in the polymer is 0.2 to 0.4; and the molar percentage of the lysine anhydride monomer unit in the polymer is 0.6 to 0.8.

[0025] The permanent antibacterial long-chain nylon polymer provided by this invention can enrich the existing types of long-chain nylons. The polylysine structural unit with controllable degree of polymerization introduced by inducing the ring-opening of the lysine anhydride can not only provide the permanent antibacterial properties required by this invention, but also act as a soft segment to copolymerize with the hard segment of the nylon 1212 macromolecular initiator to adjust the mechanical properties of the material, which can meet its application requirements in multiple fields such as medical devices, packaging materials, textiles and panels.

[0026] Unlike simple antibacterial agent composite systems, which suffer from short-lived antibacterial activity and easy loss, and lysine-based simple polymers / copolymers, which exhibit unstable antibacterial properties and molecular weight dependence, the permanent antibacterial long-chain nylon polymer provided in this invention achieves relatively stable antibacterial properties by controlling the molecular weight of the diamino-terminated nylon 1212 prepolymer monomer and its combination with the lysine anhydride monomer. It is speculated that the alternating segments of the nylon 1212 macromolecular initiator in the final structure effectively block positively charged polylysine units and are size-matched to bacteria and other microorganisms. The combined effect of these two factors achieves the excellent synergistic and long-lasting antibacterial effect described in this invention. Excessively short nylon initiator chain lengths, such as PA66, will lead to excessive accumulation of positive charges from polylysine units on the material surface, resulting in electrostatic repulsion between adjacent units and segments, thus reducing antibacterial activity. Conversely, excessively long initiator carbon chain lengths or molecular weights, such as nylon 1218, will result in an excessively low distribution of positive charges on the polylysine units used for antibacterial purposes on the material surface, leading to low bactericidal efficiency.

[0027] The present invention also provides a method for preparing the permanent antibacterial long carbon chain nylon polymer described in any of the above technical solutions, comprising the following steps:

[0028] S1) React the diamino-terminated nylon 1212 prepolymer monomer and the lysine anhydride monomer;

[0029] S2) After removing the protecting group from the product obtained in step S1), perform alkylation or guanidineation to obtain a permanent antibacterial long carbon chain nylon polymer.

[0030] This invention first reacts a diamino-terminated nylon 1212 prepolymer monomer with a lysine-containing anhydride monomer; specifically, under a protective gas atmosphere, the diamino-terminated nylon 1212 prepolymer monomer and the lysine-containing anhydride monomer undergo a ring-opening polymerization reaction in an organic solvent. The molar ratio of the diamino-terminated nylon 1212 prepolymer monomer to the lysine-containing anhydride monomer in this invention is 1:(10-400), preferably 1:(20-200), and more preferably 1:(20-100).

[0031] The reaction temperature described in this invention is 25℃~50℃, and the reaction time is 2h~24h. Excessively high reaction temperatures (above 70℃) may cause the decomposition of the lysine anhydride monomer, thereby affecting the degree of polymerization of the final copolymer and initiating ring-opening reactions. The reaction time should not exceed 48 hours; excessively long reaction times do not significantly contribute to the molecular weight of the copolymer obtained from ring-opening polymerization and may instead lead to side reactions.

[0032] The protective gas described in this invention is selected from at least one of nitrogen, helium, neon, or argon. The organic solvent described in this invention is selected from any one or more combinations of tetrahydrofuran, methanol, ethanol, dichloromethane, dimethyl sulfoxide, N,N-dimethylacetamide, N,N-dimethylformamide, N-methylpyrrolidone, ethyl acetate, and acetone, with tetrahydrofuran and N,N-dimethylformamide being the most preferred combination. The diamino-terminated nylon 1212 prepolymer monomer and the lysine anhydride monomer described in this invention are the same as described above and will not be repeated. In some embodiments of this invention, the lysine anhydride monomer is selected from lysine anhydride monomers protected by a Boc group, with the chemical formula […]. It is a commercially available product or prepared using the triphosgene method known to those skilled in the art.

[0033] The amino-terminated nylon 1212 prepolymer monomers of this invention can be obtained commercially or obtained by high-temperature polymerization of dodecanoic acid and excess dodecanoic diamine. Different molecular weights of the diamino-terminated nylon 1212 prepolymer monomers can be achieved by adjusting the molar ratio of the diacid to the diamine. If the weight-average molecular weight of the diamino-terminated nylon 1212 prepolymer monomer is below 4000 g / mol, it can be completely dissolved in polar solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone, which is beneficial for subsequent ring-opening polymerization with lysine anhydride monomers. In this invention, the diamino-terminated nylon 1212 prepolymer monomers can be obtained by high-temperature condensation as well known to those skilled in the art. The weight-average molecular weight and different alkyl carbon chain lengths can be adjusted by the ratio of dodecanoic diamine to dodecanoic acid, polymerization conditions, etc. The present invention does not impose any special restrictions on the source of the raw materials such as dodecanoic diamine and dodecanoic acid, which are generally commercially available products.

[0034] This invention involves reacting a diamino-terminated nylon 1212 prepolymer monomer with a lysine anhydride monomer, then removing the protecting group from the resulting product before alkylation or guanidineation. The method for removing the protecting group from the resulting product is not particularly limited to different methods. In some embodiments of this invention, the diamino-terminated nylon 1212 prepolymer monomer is reacted with a Boc-protected lysine anhydride monomer, and the resulting product is then deprotected with trifluoroacetic acid. This invention does not particularly limit the alkylation or guanidineation reaction; through these reactions, the deprotected lysine anhydride monomer can be converted into either a quaternary ammonium salt or a guanidine group.

[0035] Following alkylation or guanidinolation, the resulting product is precipitated to obtain the permanently antibacterial long-chain nylon polymer described herein. In some embodiments of the present invention, after alkylation or guanidinolation, the resulting product is precipitated in ethyl acetate, centrifuged, and dried to obtain the permanently antibacterial long-chain nylon polymer described herein.

[0036] This invention also provides an article, at least a portion of which is obtained from the permanently antibacterial long-chain carbon nylon polymer described in any of the above-described technical solutions and optional additional materials; the additional materials may be selectively added or omitted; in some embodiments of this invention, the additional materials are antioxidants. The articles of this invention include films, sheets, coatings, molded or shaped articles. The articles of this invention can be applied to fields such as medical devices, daily necessities, textiles, packaging materials, and panels, for example, medical catheters, masks, protective clothing, towels, carpets, and cling film. The articles of this invention can be manufactured by conventional methods, such as injection molding, blow molding, extrusion, calendering, etc., the specific operations and conditions of which are well known to those skilled in the art and can be selected according to actual needs, and will not be elaborated further here.

[0037] This invention provides a permanently antibacterial long-chain nylon polymer, its preparation method, and the resulting product. The invention uses an amino-terminated nylon 1212 prepolymer as a macromolecular initiator to initiate the ring-opening copolymerization of Boc-protected lysine NCA monomers. The polymer is then post-treated by acidification deprotection or alkyl substitution reactions to obtain the permanently antibacterial long-chain nylon polymer. Experiments show that the permanently antibacterial long-chain nylon polymer provided by this invention has broad-spectrum and long-lasting antibacterial effects, with an initial antibacterial activity exceeding 95%, and good antibacterial durability and stability; even after one month of immersion, the antibacterial activity remains above 95%. Furthermore, by changing the molar ratio of the amino-terminated nylon 1212 macromolecular initiator to the lysine NCA cyclizing monomer, its physical and mechanical properties can be adjusted. It can be used as a public health material in various fields such as medical devices, textiles, packaging materials, and various panels. Moreover, the preparation process is simple, the conditions are mild, and it is easy to achieve large-scale production. Attached Figure Description

[0038] Figure 1 This is a synthetic route diagram for preparing a permanent antibacterial long carbon chain nylon 1212 material according to the present invention;

[0039] Figure 2 The image shows the antibacterial effect test results of the antibacterial nylon 1212 materials prepared in Comparative Example 2 and Example 15 against Staphylococcus aureus. Detailed Implementation

[0040] This invention discloses a permanent antibacterial long-chain carbon nylon polymer, its preparation method, and the resulting product. Those skilled in the art can refer to this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments; those skilled in the art will clearly be able to modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0041] Preparation of Boc-protected lysine anhydride cyclic monomers by the triphosgene method:

[0042] Taking Boc-L-lysine anhydride as an example, commercially available Boc-L-lysine (10.0 g, 40.6 mmol) was placed in a 500 mL three-necked round-bottom flask, and anhydrous tetrahydrofuran was added to prepare a solution. Under nitrogen protection, a tetrahydrofuran solution of triphosgene (4.4 g, 14.9 mmol) was added dropwise. The resulting mixture was stirred at 50 °C for 10 minutes (200 r / min), and the crude product was obtained by rotary evaporation. The crude product was recrystallized three times using ethyl acetate and n-hexane, and the final product was a white powder. Its structure and purity were determined by NMR. Both Boc-D-lysine anhydride and Boc-DL-lysine anhydride can be obtained by the above method, and will not be described in detail here.

[0043] Preparation of diamino-terminated nylon 1212 macromolecular initiator by high-temperature condensation:

[0044] Dodecanoic acid and dodecanoic acid were weighed and mixed according to a certain molar ratio and added to a polymerization reactor. Then, a certain amount of deionized water and 2‰ antioxidant 1010 were added. The reactor was sealed, and the air inside was replaced with high-purity nitrogen 3-5 times. Heating was then started, and when the temperature reached 150℃, stirring was initiated (150 r / min), and the reaction was maintained at a constant temperature for 30 minutes to ensure thorough melting and mixing of the materials. The reaction temperature was then increased to 200℃ and maintained for 2 hours. Subsequently, the pressure inside the reactor was slowly released through a valve until atmospheric pressure was reached. The material was then removed from the bottom outlet, cooled, pulverized, and dried to obtain a nylon 1212 prepolymer with a predetermined molecular weight and a structure of Formula 2. Its molecular weight and amino content in the structure were determined by acid-base titration.

[0045] Preparation of Nylon 1212-polylysine copolymer by NCA ring-opening polymerization:

[0046] 1.2 g of Boc-L-Lys-NCA was dissolved in anhydrous tetrahydrofuran and added via syringe to an anhydrous N,N-dimethylformamide solution containing a certain amount of diamino-terminated nylon 1212 macromolecular initiator, resulting in a mixed solution with a specific molar ratio of macromolecular initiator to lysine cyclic monomer. After stirring for 4-6 hours under nitrogen protection and at a controlled temperature, the solution was filtered, washed three times with diethyl ether, and dried in a vacuum drying oven to obtain the nylon 1212-polylysine copolymer containing the Boc protecting group shown in Formula 4.

[0047] This invention prepares nylon 1212-polylysine copolymer via NCA ring-opening polymerization, followed by acid deprotection of the halogenated compound to obtain a permanently antibacterial long-chain nylon 1212 material, such as... Figure 1 As shown, Figure 1 The reaction flow diagram for preparing the permanent antibacterial long carbon chain nylon 1212 material of this invention is shown in the figure.

[0048] The present invention will be further described below with reference to the embodiments:

[0049] Example 1

[0050] The diamine and dicarboxylic acid were weighed according to a molar ratio of 1.5:1 and condensed at high temperature to obtain a diamino-terminated nylon 1212 macromolecular initiator with a theoretical weight-average molecular weight of 1000 g / mol and an actual measured value of 975 g / mol.

[0051] The reaction was carried out at room temperature under nitrogen atmosphere for 6 hours with a molar ratio of 30:1 between Boc-L-lysine anhydride monomer and diamino-terminated nylon 1212 initiator. Post-treatment involved three washes with diethyl ether precipitation and vacuum drying to obtain a nylon 1212-polylysine copolymer containing Boc protecting groups. This copolymer was then dissolved in 4 mL of trifluoroacetic acid, stirred at room temperature for 12 hours for acid hydrolysis, filtered, and lyophilized to obtain an amino-nylon 1212-polylysine copolymer product with a number-average molecular weight of 4000, named PAL. 4000 -NH2.

[0052] Example 2

[0053] Based on Example 1, a certain amount of PAL 4000 -NH2 was dispersed in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), followed by the addition of iodomethane in an excess of 4 times the amount of lysine structural units. The reaction was carried out at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, and dialyzed against 0.10 mol / L NaCl solution for 24 hours, followed by dialyzed against deionized water for another 24 hours. After lyophilization, the trimethyl quaternary ammonium salted nylon 1212-polylysine copolymer product was obtained and named PAL. 4000 -N(CH3)3.

[0054] Example 3

[0055] Based on Example 1, a certain amount of PAL 4000 -NH2 was dispersed in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), followed by the addition of iodobutane in an excess of 4 times the amount of lysine structural units. The reaction was carried out at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, and dialyzed against 0.10 mol / L NaCl solution for 24 hours, followed by dialyzed against deionized water for another 24 hours. After lyophilization, the product was obtained as a tributyl quaternary ammonium salt-treated nylon 1212-polylysine copolymer, named PAL. 4000 -N(C4H9)3.

[0056] Example 4

[0057] Based on Example 1, a certain amount of PAL 4000 -NH2 was dispersed in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), followed by the addition of iodohexane in an excess of 4 times the amount of lysine structural units. The reaction was carried out at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, and dialyzed against 0.10 mol / L NaCl solution for 24 hours, followed by dialyzed against deionized water for another 24 hours. After lyophilization, the product was obtained as a trihexyl quaternary ammonium salt-treated nylon 1212-polylysine copolymer, named PAL. 4000 -N(C6H 13 3.

[0058] Example 5

[0059] Based on Example 1, 0.5 mol of 1H-pyrazole-1-formamidinium hydrochloride and 0.5 mol of potassium carbonate were mixed in equimolar amounts and added to an aqueous solution of the product from Example 1 with a concentration of 2 wt% to obtain a mixed solution. After purging the above mixed solution with nitrogen three times, the mixture was stirred and heated at 55°C for 12 h (150 r / min). The crude product was dialyzed for 1 day using a dialysis bag with a molecular weight cutoff of 3500. The dialyzed product was concentrated and freeze-dried to obtain a guanidine-modified nylon 1212-polylysine copolymer product, named PAL. 4000 -CN3H4.

[0060] Example 6

[0061] The diamine and dicarboxylic acid were weighed according to a molar ratio of 4:3, and condensed at high temperature to obtain a diamino-terminated nylon 1212 macromolecular initiator with a theoretical weight-average molecular weight of 1500 g / mol and an actual measured value of 1476 g / mol.

[0062] The reaction was carried out at room temperature under nitrogen for 6 hours with a molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 30:1. Post-treatment involved washing three times with diethyl ether precipitation and vacuum drying to obtain a nylon 1212-polylysine copolymer containing Boc protecting groups. This copolymer was then dissolved in 4 mL of trifluoroacetic acid, stirred at room temperature for 12 hours for acid hydrolysis, filtered, and lyophilized to obtain an amino-nylon 1212-polylysine copolymer product with a number-average molecular weight of 6000, named PAL. 6000 -NH2.

[0063] Example 7

[0064] Based on Example 6, a certain amount of PAL 6000 -NH2 was dispersed in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), followed by the addition of iodoethane in an excess of 4 times the amount of lysine structural units. The reaction was carried out at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, and dialyzed against 0.10 mol / L NaCl solution for 24 hours, followed by dialyzed against deionized water for another 24 hours. After lyophilization, the product was obtained as a triethyl-quaternized nylon 1212-polylysine copolymer, named PAL. 6000 -N(C2H5)3.

[0065] Example 8

[0066] Based on Example 6, 0.5 mol of 1H-pyrazole-1-formamidinium hydrochloride and 0.5 mol of potassium carbonate were mixed in equimolar amounts and added to an aqueous solution of the product from Example 6 with a concentration of 2 wt% to obtain a mixed solution. After purging the above mixed solution with nitrogen three times, the mixture was stirred and heated at 55°C for 12 h (150 r / min). The crude product was dialyzed for 1 day using a dialysis bag with a molecular weight cutoff of 1000. The dialyzed product was concentrated and freeze-dried to obtain a guanidine-modified nylon 1212-polylysine copolymer product, named PAL. 6000 -CN3H4.

[0067] Example 9

[0068] The diamine and dicarboxylic acid were weighed according to a molar ratio of 1.1:1 and condensed at high temperature to obtain a diamino-terminated nylon 1212 macromolecular initiator with a theoretical weight-average molecular weight of 3500 g / mol and an actual measured value of 3482 g / mol.

[0069] The reaction was carried out at room temperature under nitrogen for 6 hours with a molar ratio of 30:1 between Boc-L-lysine anhydride monomer and diamino-terminated nylon 1212 initiator under nitrogen atmosphere. Post-treatment involved three washes with diethyl ether precipitation and vacuum drying to obtain a nylon 1212-polylysine copolymer containing Boc protecting groups. This copolymer was then dissolved in 4 mL of trifluoroacetic acid, stirred at room temperature for 12 hours for acid hydrolysis, filtered, and lyophilized to obtain an amino-nylon 1212-polylysine copolymer product with a number-average molecular weight of 8000, named PAL. 8000 -NH2.

[0070] Example 10

[0071] Based on Example 9, a certain amount of PAL 8000 -NH2 was dispersed in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), followed by the addition of iodomethane in an excess of 4 times the amount of lysine structural units. The reaction was carried out at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, and dialyzed against 0.10 mol / L NaCl solution for 24 hours, followed by dialyzed against deionized water for another 24 hours. After lyophilization, the trimethyl quaternary ammonium salted nylon 1212-polylysine copolymer product was obtained and named PAL. 8000 -N(CH3)3.

[0072] Example 11

[0073] Based on Example 9, 0.5 mol of 1H-pyrazole-1-formamidinium hydrochloride and 0.5 mol of potassium carbonate were mixed in equimolar amounts and added to an aqueous solution of the product from Example 6 with a concentration of 2 wt% to obtain a mixed solution. After purging the above mixed solution with nitrogen three times, the mixture was stirred and heated at 55°C for 12 h (150 r / min). The crude product was dialyzed for 1 day using a dialysis bag with a molecular weight cutoff of 1000. The dialyzed product was concentrated and freeze-dried to obtain a guanidine-modified nylon 1212-polylysine copolymer product, named PAL. 8000 -CN3H4.

[0074] Example 12

[0075] The diamine and dicarboxylic acid were weighed according to a molar ratio of 1.5:1 and condensed at high temperature to obtain a diamino-terminated nylon 1212 macromolecular initiator with a theoretical weight-average molecular weight of 1000 g / mol and an actual measured value of 975 g / mol.

[0076] The reaction was carried out at room temperature under nitrogen for 6 hours with a molar ratio of 100:1 between Boc-L-lysine anhydride monomer and diamino-terminated nylon 1212 initiator under nitrogen atmosphere. Post-treatment involved three washes with diethyl ether precipitation and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protecting groups. A certain amount of the amino product obtained after acid hydrolysis was dissolved in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), followed by the addition of iodomethane in excess of 4 times the amount of lysine structural units. The reaction was carried out at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, dialyzed against 0.10 mol / L NaCl solution for 24 hours, followed by dialyzed against deionized water for another 24 hours. After lyophilization, a trimethyl quaternary ammonium-treated nylon 1212-polylysine copolymer with a number average molecular weight of 12000 was obtained and named PAL. 12000 -N(CH3)3.

[0077] Example 13

[0078] The diamine and dicarboxylic acid were weighed according to a molar ratio of 1.5:1 and condensed at high temperature to obtain a diamino-terminated nylon 1212 macromolecular initiator with a theoretical weight-average molecular weight of 1000 g / mol and an actual measured value of 975 g / mol.

[0079] The reaction was carried out at room temperature under nitrogen for 6 hours with a molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 100:1. Post-treatment involved washing three times with diethyl ether precipitation and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protecting groups. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2 wt% solution. 0.5 mol of 1H-pyrazole-1-formamidinium hydrochloride and 0.5 mol of potassium carbonate were added. After purging with nitrogen three times, the reaction was carried out at 55 °C with stirring and heating for 12 hours (150 r / min). The product was then concentrated and lyophilized after dialysis to obtain guanidino-Nylon 1212-polylysine copolymer, named PAL. 12000 -CN3H4.

[0080] Example 14

[0081] The diamine and dicarboxylic acid were weighed according to a molar ratio of 1.5:1 and condensed at high temperature to obtain a diamino-terminated nylon 1212 macromolecular initiator with a theoretical weight-average molecular weight of 1000 g / mol and an actual measured value of 975 g / mol.

[0082] The reaction was carried out at room temperature under nitrogen for 6 hours with a molar ratio of 150:1 between Boc-L-lysine anhydride monomer and diamino-terminated nylon 1212 initiator under nitrogen atmosphere. Post-treatment involved three washes with diethyl ether precipitation and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protecting groups. A certain amount of the amino product obtained after acid hydrolysis was dissolved in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), followed by the addition of iodomethane in excess of 4 times the amount of lysine structural units. The reaction was carried out at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, dialyzed against 0.10 mol / L NaCl solution for 24 hours, followed by dialyzed against deionized water for another 24 hours. After lyophilization, a trimethyl quaternary ammonium-treated nylon 1212-polylysine copolymer with a number average molecular weight of 16000 was obtained and named PAL. 16000 -N(CH3)3.

[0083] Example 15

[0084] The diamine and dicarboxylic acid were weighed according to a molar ratio of 1.5:1 and condensed at high temperature to obtain a diamino-terminated nylon 1212 macromolecular initiator with a theoretical weight-average molecular weight of 1000 g / mol and an actual measured value of 975 g / mol.

[0085] The reaction was carried out at room temperature under nitrogen for 6 hours with a molar ratio of 150:1 between Boc-L-lysine anhydride monomer and diamino-terminated nylon 1212 initiator under nitrogen atmosphere. Post-treatment involved three washes with diethyl ether precipitation and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protecting groups. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2 wt% solution. 0.5 mol of 1H-pyrazole-1-formamidinium hydrochloride and 0.5 mol of potassium carbonate were added. After three nitrogen purgings, the reaction was carried out at 55 °C with stirring and heating for 12 hours (150 r / min). The dialyzed product was concentrated and lyophilized to obtain a guanidino-nylon 1212-polylysine copolymer product with a number average molecular weight of 16000, named PAL. 16000 -CN3H4.

[0086] Comparative Example 1

[0087] The diamine and dicarboxylic acid were weighed according to a molar ratio of 1.5:1 for octadecanoic acid and dodecanoic acid, and then condensed at high temperature to obtain a diamino-terminated nylon 1218 macromolecular initiator with a theoretical weight-average molecular weight of 1000 g / mol and an actual measured value of 1015 g / mol.

[0088] The reaction was carried out at room temperature under nitrogen for 6 hours with a molar ratio of 150:1 between Boc-L-lysine anhydride monomer and diamino-terminated nylon 1218 initiator. Post-treatment involved three washes with diethyl ether precipitation and vacuum drying to obtain nylon 1018-polylysine copolymer containing Boc protecting groups. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2 wt% solution. 0.5 mol of 1H-pyrazole-1-formamidinium hydrochloride and 0.5 mol of potassium carbonate were added. After three nitrogen purgings, the reaction was carried out at 55 °C with stirring and heating for 12 hours (150 r / min). The dialyzed product was concentrated and lyophilized to obtain guanidino-nylon 1218-polylysine copolymer with a number average molecular weight of 16000.

[0089] Comparative Example 2

[0090] The diamine and diacid were weighed according to a molar ratio of hexamethylenediamine to adipic acid of 1.5:1, and condensed at high temperature to obtain a diamino-terminated nylon 66 macromolecular initiator with a theoretical weight-average molecular weight of 1000 g / mol, and the measured value was 997 g / mol.

[0091] The reaction was carried out at room temperature under nitrogen atmosphere for 6 hours with a molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 66 initiator of 150:1. Post-treatment involved three washes with diethyl ether precipitation and vacuum drying to obtain nylon 66-polylysine copolymer containing Boc protecting groups. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2 wt% solution. 0.5 mol of 1H-pyrazole-1-formamidinium hydrochloride and 0.5 mol of potassium carbonate were added. After three nitrogen purgings, the reaction was carried out at 55 °C with stirring and heating for 12 hours (150 r / min). The dialyzed product was concentrated and lyophilized to obtain guanidino-nylon 66-polylysine copolymer product with a number average molecular weight of 16000.

[0092] Comparative Example 3

[0093] VESTAMID Care ML16 Nylon 12 resin from Evonik GmbH, Germany.

[0094] Comparative Example 4

[0095] Arkema, France 7033SA01 Medical-grade elastomer material.

[0096] Comparative Example 5

[0097] Take 10g of polyhexamethylene biguanide hydrochloride (number average molecular weight 241) and 990g of nylon 12 elastomer ( 7033SA01 (melting point 174℃) was mixed evenly in a high-speed mixer and then melt-extruded in a twin-screw extruder at an extrusion temperature of 200℃, a screw speed of 130 rpm, and a material residence time of 1.5 min. After melt extrusion, guanidine-modified antibacterial nylon 12 elastomer was obtained.

[0098] Comparative Example 6

[0099] Take 3g of commercially available nano-zirconium phosphate silver-loaded antibacterial agent (average particle size 30-50nm) and 997g of nylon 12 elastomer ( 7033SA01 (melting point 174℃) was mixed evenly in a high-speed mixer and then melt-extruded in a twin-screw extruder at an extrusion temperature of 200℃, a screw speed of 130 rpm, and a material residence time of 1.5 min. After melt extrusion, an inorganic antibacterial agent modified antibacterial nylon 12 elastomer was obtained.

[0100] Antibacterial effect test:

[0101] The antibacterial effect was tested according to the Chinese National Standard GB / T 31402-2015 "Test Method for Antibacterial Properties of Plastic Surfaces". The sample size and culture conditions were adjusted according to actual conditions. The specific operation is as follows: The permanently antibacterial nylon 1212 material prepared in Examples 1-15 and the nylon 12 and its elastomer materials prepared in Comparative Examples 1-6 were pressed into 1cm × 1cm square sheets. These sheets were sterilized by irradiation under a UV lamp for 30 minutes. Then, a prepared bacterial solution was dropped onto the sheet, covered with a PE film, and incubated at 37°C for 6 hours. After ultrasonication for 3 minutes, the solution was diluted 100 times and placed on a solid culture medium, incubated at 37°C for 24 hours. The conventional nylon 6 material obtained in Comparative Examples 1-2 served as the control group. The bacteria used for testing were Staphylococcus aureus (S. aureus) ATCC6538 and Escherichia coli (E. coli) ATCC25922. The results are shown in Table 1, which presents the antibacterial test results of the antibacterial nylon materials in Examples 1-15 and Comparative Examples 1-6. Figure 2 As shown, Figure 2 The image shows the antibacterial effect test results of the antibacterial nylon 1212 materials prepared in Comparative Example 2 and Example 15 against Staphylococcus aureus.

[0102] Table 1

[0103]

[0104]

[0105] As can be seen from the test results in Table 1, the antibacterial nylon material provided by the present invention has a broad-spectrum antibacterial effect and exhibits excellent antibacterial properties.

[0106] Long-lasting antibacterial effect test:

[0107] The square sheets prepared in the above nine examples containing trimethyl quaternary ammonium salt and guanidine group and comparative examples 3-4 were soaked in water at 37°C for one month, and the long-term antibacterial properties were tested according to the above test method. The antibacterial test results are shown in Table 2. Table 2 shows the long-term antibacterial test results of the antibacterial nylon materials of the examples and comparative examples 3-4.

[0108] Table 2

[0109]

[0110] As shown in Table 2, the antibacterial nylon material provided by this invention exhibits a long-lasting antibacterial effect, with a sterilization rate exceeding 95% even after one month of immersion. However, the antibacterial durability of materials obtained after immersion is significantly reduced when organic guanidine salts or nano-zirconium phosphate silver-loaded antibacterial agents are introduced and combined with the nylon elastomer. This demonstrates that the elastomer material provided by this invention possesses excellent antibacterial durability. Unlike simple antibacterial agent composite systems, which have short-lived antibacterial activity and are prone to loss, and lysine-based simple polymers / copolymers, which exhibit unstable antibacterial performance and molecular weight dependence, the series of permanently long carbon chain antibacterial nylon materials provided by this invention can achieve relatively stable antibacterial performance by controlling the molecular weight of the nylon 1212 macromolecular initiator and its initiation ratio with the lysine anhydride monomer. It is speculated that the alternating segments derived from the nylon 1212 macromolecular initiator in the final structure can effectively block positively charged polylysine units, and their size compatibility with bacteria and other microorganisms contributes to the excellent synergistic and long-lasting antibacterial effect described in this invention. Too short a nylon initiator chain length, such as PA66, will cause excessive accumulation of positive charges from polylysine units on the material surface, leading to electrostatic repulsion between adjacent units and adjacent chain segments, resulting in decreased antibacterial activity. Conversely, too long an initiator carbon chain length or molecular weight, such as choosing nylon 1218, will result in too low a positive charge distribution on the material surface of the polylysine units used for antibacterial purposes, leading to low bactericidal efficiency.

[0111] Mechanical performance testing:

[0112] The antibacterial nylon materials obtained in Examples 12-15 and Comparative Examples 1-4 were injection molded into 40mm×4mm×2mm specimens, and mechanical properties were tested. The results are shown in Table 3. Table 3 shows the mechanical property test results of the antibacterial nylon materials in Examples 12-15 and Comparative Examples 1-2.

[0113] Table 3

[0114]

[0115] As shown in Tables 1-2 and 3, the permanent antibacterial nylon 1212 material of this application not only has a significant antibacterial effect ( Figure 2 In particular, the long-lasting antibacterial effect is far superior to that of the antibacterial composite materials in Comparative Examples 1-2 and commercially available nylon and elastomers without antibacterial effect (see Comparative Examples 3-4). Furthermore, the mechanical properties of the antibacterial nylon 1212 material can be adjusted by changing the ratio of the hard segment of the diamino-terminated nylon 1212 macromolecular initiator to the soft segment of polylysine, achieving mechanical properties comparable to those of the nylon elastomer material in Comparative Example 4. In contrast, the mechanical properties of Comparative Examples 5-6 decreased significantly after incorporating the antibacterial component, affecting subsequent processing and use.

[0116] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A permanently antibacterial long-chain carbon nylon polymer, characterized in that, It includes a diamino-terminated nylon 1212 prepolymer unit and a lysine anhydride monomer unit; The diamino-terminated nylon 1212 prepolymer unit has the structure of formula Ia; Formula Ia; The number of repetitions of the chain segment to which it belongs; The lysine anhydride monomer unit has a structure of formula Ib. Formula Ib; Wherein, R1, R2, and R3 are independently selected from hydrogen, substituted or unsubstituted C1~C. 16 One of the alkyl groups; or, R1, R2 and R3 and the N attached to them together constitute a substituted or unsubstituted guanidine group; The m represents the number of repetitions of the chain segment to which it belongs.

2. The permanently antibacterial long-chain carbon nylon polymer according to claim 1, characterized in that, The diamino-terminated nylon 1212 prepolymer unit is derived from diamino-terminated nylon 1212 prepolymer monomers with a weight-average molecular weight of 600 g / mol to 20000 g / mol.

3. The permanently antibacterial long-chain carbon nylon polymer according to claim 1, characterized in that, The sum of n and m is an integer between 10 and 500.

4. The permanently antibacterial long-chain nylon polymer according to claim 1, characterized in that, The weight-average molecular weight of the permanently antibacterial long-chain nylon polymer is 2000 g / mol to 40000 g / mol.

5. The permanently antibacterial long-chain carbon nylon polymer according to claim 1, characterized in that, R1, R2 and R3 are independently selected from one of hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-hexyl, n-heptyl or n-octyl.

6. A method for preparing the permanent antibacterial long-chain nylon polymer according to any one of claims 1 to 5, characterized in that, Includes the following steps: S1) React the diamino-terminated nylon 1212 prepolymer monomer with the lysine anhydride monomer; The diamino-terminated nylon 1212 prepolymer monomer has a Formula II structure; Formula II; The lysine anhydride monomer has a structure of formula III. Formula III; Wherein, R is a protecting group; S2) After removing the protecting group from the product obtained in step S1), perform alkylation or guanidineation to obtain a permanent antibacterial long carbon chain nylon polymer.

7. The preparation method according to claim 6, characterized in that, In step S1), the reaction temperature is 25℃~50℃, and the reaction time is 2 h~24 h.

8. An article, characterized in that, It is at least partially derived from the permanent antibacterial long-chain nylon polymer and additives as described in any one of claims 1 to 5.

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