Permanent antibacterial long carbon chain nylon polymer as well as preparation method and product thereof

Abstract

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

Description

Technical Field

[0001] The invention relates to the technical field of functional nylon preparation, in particular to a permanent antibacterial long carbon chain nylon polymer and a preparation method and product thereof. Background Art

[0002] Long-chain polyamide (LCPA) generally refers to a chain segment in which the length of the unit methylene group is 10 or more, such as PA10, PA12, PA1012, PA1212, etc. Compared with short-chain polyamides represented by PA6 and PA66, the longer freely stretchable methylene chains in its structure exhibit better physical and mechanical properties such as flexibility, as well as characteristics such as low temperature resistance, low density and lower water absorption. Among the commercialized LCPAs, the nylon 1212 series and its elastomer materials are the most common, and are often used to replace silicone rubber and fluororubber. They are widely used in pharmaceutical packaging, drug solution and blood storage and infusion, various catheters, and medical equipment accessories. However, bacteria can easily adhere to, grow, and form biofilms on the surface of materials or devices, thus causing bacterial infections.

[0003] The prior art provides some antibacterial nylon materials, which can be mainly divided into two categories: composite reinforced nylon and permanent antibacterial nylon, and mainly focus on nylon 6 and its related composites. Regarding composite reinforced nylon, such as CN201310003682.7, CN201410061129.3, CN202310429959.6, etc., its antibacterial properties are mainly derived from small molecule antibacterial agents such as inorganic silver added therein. However, the antibacterial effects of the antibacterial materials provided by these solutions are poor, and the added small molecule antibacterial agents are easy to precipitate, which not only leads to a decrease in antibacterial properties, but also causes potential safety issues such as cytotoxicity.

[0004] Regarding permanent antibacterial nylon, such as CN202310695750.4, CN202110604927.6, CN202110960422.3, CN202210355249.9, etc., its antibacterial properties are achieved by introducing antibacterial units such as Schiff base, guanidine, and imidazolium salts into the polymer structure of nylon 6. However, nylon 6 material itself has a high water absorption rate, and its products easily absorb moisture in the environment, which provides a good breeding ground for bacteria and fungi, and is not suitable for use in packaging, panels, medical devices and other fields. Summary of the invention

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

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

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

[0008]

[0009] The n represents the number of repetitions of the chain link in which it is located;

[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-C 16 One of the alkyl groups; or, the R1, R2 and R3 and the N to which they are connected together constitute a substituted or unsubstituted guanidine group;

[0013] The m represents the number of repetitions of the link in which it is located.

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

[0015] The diamino-terminated nylon 1212 prepolymer unit of the present invention is derived from a diamino-terminated nylon 1212 prepolymer monomer 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 a diamino-terminated nylon 1212 prepolymer monomer with a weight average molecular weight of 600 g / mol to 4000 g / mol. The diamino-terminated nylon 1212 prepolymer monomer is also called a diamino-terminated nylon 1212 macroinitiator, which has a structure of formula II.

[0016]

[0017] Among them, the n is the same as described above and will not be repeated here.

[0018] The lysine internal anhydride monomer unit of the present invention is derived from a lysine internal anhydride monomer. In certain embodiments of the present invention, the lysine internal anhydride monomer is derived from a compound having a structure of formula III:

[0019]

[0020] Wherein, the R is a protecting group. In certain embodiments of the present invention, the protecting group is selected from tert-butyloxycarbonyl (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 to C 16 or, the R1, R2 and R3 and the N to which they are connected together constitute a substituted or unsubstituted guanidine group. In some embodiments of the present invention, the R1, R2 and R3 are independently selected from hydrogen, substituted or unsubstituted C1 to C 16 Straight chain alkyl or C1~C 16 In some other embodiments of the present 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 ratio of the diamino-terminated nylon 1212 prepolymer unit in the present invention to the polymer is 0.1 to 0.8; the molar ratio of the lysine anhydride monomer unit to the polymer is 0.2 to 0.9; and the molar ratio of the sum of the diamino-terminated nylon 1212 prepolymer unit and the lysine anhydride monomer unit to the polymer is 1.

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

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

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

[0026] Different from the simple antibacterial agent composite system, which has short antibacterial activity and is easy to lose, and the simple polymer / copolymer based on lysine, which has unstable antibacterial performance and molecular weight dependence, the permanent antibacterial long carbon chain nylon polymer provided by the present invention can obtain relatively stable antibacterial performance by regulating the molecular weight of the double amino-terminated nylon 1212 prepolymer monomer and combining it with the lysine internal anhydride monomer. It is speculated that the alternating chain segments derived from the nylon 1212 macromolecular initiator in the final structure can effectively block the positively charged polylysine unit, and the size matching with the existence of microorganisms such as bacteria, and the two work together to achieve the excellent synergistic long-term antibacterial effect of the structure described in the present invention. Too short nylon initiator chain length, such as PA66, will cause too much positive charge from the polylysine unit to accumulate on the surface of the material, and the electrostatic repulsion between adjacent units and adjacent segments will lead to a decrease in antibacterial activity; on the contrary, too long initiator carbon chain length or molecular weight, such as selecting nylon 1218, will cause the positive charge distribution of the polylysine unit used for antibacterial on the surface of the material to be too low, resulting in low sterilization 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) reacting a diamino-terminated nylon 1212 prepolymer monomer and a lysine internal anhydride monomer;

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

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

[0031] The reaction temperature of the present invention is 25°C to 50°C, and the reaction time is 2h to 24h. Too high (over 70°C) reaction temperature may lead to the decomposition of lysine internal anhydride monomer, thereby affecting the degree of polymerization of the final copolymer and initiating the occurrence of ring-opening reaction. The reaction time should not exceed 48 hours. Too long reaction time does not contribute much to the molecular weight of the copolymer obtained by ring-opening polymerization, but instead leads to the occurrence of side reactions.

[0032] The protective gas of the present invention is selected from at least one of nitrogen, helium, neon or argon. The organic solvent of the present 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, among which the combination of tetrahydrofuran and N,N-dimethylformamide is the best. The diamino-terminated nylon 1212 prepolymer monomer and the lysine anhydride monomer of the present invention are the same as those described above and will not be repeated. In certain embodiments of the present invention, the lysine anhydride monomer of the present invention is selected from lysine anhydride monomer protected by a Boc group, and its chemical formula is It is a general commercial product or can be prepared by the triphosgene method well known to those skilled in the art.

[0033] The amino-terminated nylon 1212 prepolymer monomer of the present invention can be purchased, or it can be obtained by high-temperature polymerization of dodecanedioic acid and excess dodecanedioamine. The bis-amino-terminated nylon 1212 prepolymer monomer of different molecular weights can be achieved by adjusting the molar feed ratio of dibasic acid and diamine. If the weight average molecular weight of the bis-amino-terminated nylon 1212 prepolymer monomer is within 4000g / mol, it can be completely dissolved in polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, etc., so as to facilitate the subsequent ring-opening polymerization reaction with lysine anhydride monomer. In the present invention, the bis-amino-terminated nylon 1212 prepolymer monomer can be obtained according to the high-temperature condensation well known to those skilled in the art, wherein the weight average molecular weight and different alkyl carbon chain lengths can be obtained by adjusting the feed ratio of dodecanedioamine to dodecanedioic acid, polymerization conditions, etc. The present invention has no special restrictions on the sources of the raw materials such as dodecane diamine and dodecane dicarboxylic acid, which are generally commercially available products.

[0034] The present invention reacts a diamino-terminated nylon 1212 prepolymer monomer with a lysine anhydride monomer, removes the protecting group from the obtained product, and then performs an alkylation reaction or a guanidation reaction. The method for removing the protecting group from the obtained product of the present invention has no special limitation on the removal method of different protecting groups; in some embodiments of the present invention, the present invention reacts a diamino-terminated nylon 1212 prepolymer monomer with a lysine anhydride monomer protected by a Boc group, and then removes the protecting group from the obtained product with trifluoroacetic acid. The present invention has no special limitation on the alkylation reaction or the guanidation reaction, and the lysine anhydride monomer after the protecting group is removed can be converted into any one of a quaternary ammonium salt and a guanidinium group through the alkylation reaction or the guanidation reaction.

[0035] After the alkylation reaction or guanidation reaction is carried out in the present invention, the obtained product is subjected to sedimentation treatment to obtain the permanent antibacterial long carbon chain nylon polymer of the present invention. In some embodiments of the present invention, after the alkylation reaction or guanidation reaction is carried out, the obtained product is sedimented in ethyl acetate, centrifuged and dried to obtain the permanent antibacterial long carbon chain nylon polymer of the present invention.

[0036] The present invention also provides a product, at least a part of which is obtained from the permanent antibacterial long carbon chain nylon polymer described in any of the above technical solutions and an optional additional material; the additional material can be selectively added or not added; in certain embodiments of the present invention, the additional material is an antioxidant. The product of the present invention includes a film, a sheet, a coating, a formed or molded product. The product of the present invention can be applied to the fields of medical devices, daily necessities, textiles, packaging materials and panels, such as medical catheters, masks, protective clothing, towels, carpets, plastic wrap, etc. The product of the present invention can be manufactured in a conventional manner, such as by injection molding, blow molding, extrusion, calendering, etc. The specific operations and conditions are well known to those skilled in the art and can be selected according to actual needs, which will not be repeated here.

[0037] The present invention provides a permanent antibacterial long carbon chain nylon polymer and a preparation method and product thereof. The present invention uses a nylon 1212 prepolymer terminated with amino groups at both ends as a macromolecular initiator to initiate the ring-opening copolymerization of a Boc-protected lysine internal anhydride monomer, and then prepares a permanent antibacterial long carbon chain nylon polymer through post-treatment such as acidification deprotection or alkyl substitution reaction. Experiments show that the permanent antibacterial long carbon chain nylon polymer provided by the present invention has a broad-spectrum and long-lasting antibacterial effect, and its initial antibacterial property reaches more than 95%, and the antibacterial persistence and stability are good. The antibacterial property remains above 95% after soaking for one month. In addition, by changing the molar ratio of the nylon 1212 macromolecular initiator terminated with amino groups at both ends to the lysine NCA ring-forming monomer, the physical and mechanical properties thereof can also be adjusted, and the 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 it is easy to realize large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A synthetic route for preparing a permanent antibacterial long carbon chain nylon 1212 material of the present invention;

[0039] Figure 2 This is a test chart of the antibacterial effect of the antibacterial nylon 1212 material prepared in Comparative Example 2 and Example 15 on Staphylococcus aureus. DETAILED DESCRIPTION

[0040] The present invention discloses a permanent antibacterial long carbon chain nylon polymer and a preparation method and product thereof. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It is particularly important to point out that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to realize and apply the technology of the present invention.

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

[0042] Taking Boc-L-lysine anhydride as an example, commercially available Boc-L-lysine (10.0g, 40.6mmol) was placed in a 500mL three-necked round-bottom flask, and anhydrous tetrahydrofuran was added to form a solution. A tetrahydrofuran solution of triphosgene (4.4g, 14.9mmol) was added dropwise under nitrogen protection, and the resulting mixed solution was stirred for reaction at 50°C for 10 minutes (200r / min), and the crude product obtained after rotary evaporation. Ethyl acetate and n-hexane were used for recrystallization three times, and the final product was a white powdery solid, and its structure and purity were determined by nuclear magnetic resonance. Both Boc-D-lysine anhydride and Boc-DL-lysine anhydride can be obtained by the above method, and will not be repeated.

[0043] Preparation of diamino-terminated nylon 1212 macroinitiator by high temperature condensation method:

[0044] Weigh the raw materials of dodecanediamine and dodecanedioic acid according to a certain molar ratio, mix them and add them to the polymerization reactor, then add a certain amount of deionized water and 2‰ antioxidant 1010, seal the reactor and replace the air in the reactor with high-purity nitrogen, repeat 3 to 5 times; then turn on the heating, start stirring (150r / min) when the temperature reaches 150°C and react at a constant temperature for 30min to make the materials fully melt and mix; then increase the reaction temperature to 200°C and react at a constant temperature for 2h; then slowly release the pressure in the reactor through the valve until it reaches normal pressure, then take out the material from the lower discharge port, and after cooling, crushing and drying, obtain a double amino-terminated nylon 1212 prepolymer with a preset molecular weight having a structure of formula 2. Determine its molecular weight and amino content in the structure 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 to an anhydrous N,N-dimethylformamide solution containing a certain amount of diamino-terminated nylon 1212 macroinitiator through a syringe to obtain a mixed solution with a certain molar ratio of macroinitiator to lysine cyclic monomer. After stirring for 4-6 hours at a certain temperature under nitrogen protection, the mixture was filtered and washed with ether three times, and dried in a vacuum drying oven to obtain a nylon 1212-polylysine copolymer containing a Boc protective group as shown in Formula 4.

[0047] The present invention prepares nylon 1212-polylysine copolymer by NCA ring-opening polymerization, and then acid deprotects the halide to obtain a permanent antibacterial long carbon chain nylon 1212 material, such as Figure 1 As shown, Figure 1 The present invention is a reaction flow chart for preparing permanent antibacterial long carbon chain nylon 1212 material.

[0048] The present invention will be further described below in conjunction with embodiments:

[0049] Example 1

[0050] The diamine and the dibasic acid were weighed according to the molar ratio of dodecanediamine to dodecanedioic acid of 1.5:1, and condensed at high temperature to obtain a diamino-terminated nylon 1212 macroinitiator with a theoretical weight average molecular weight of 1000 g / mol, and the actual measured value was 975 g / mol.

[0051] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 30:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the nylon 1212-polylysine copolymer containing Boc protective group was obtained by post-treatment using ether precipitation, washing three times and vacuum drying. The copolymer was then dissolved in 4 mL of trifluoroacetic acid, stirred at room temperature for 12 hours, acid-lyzed, filtered and freeze-dried 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), and then iodomethane was added in an excess of 4 times the amount of the lysine structural unit, and 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 was first dialyzed with 0.10 mol / L NaCl solution for 24 hours, and then dialyzed with deionized water for another 24 hours. After freeze-drying, a trimethyl ammonium salt-containing nylon 1212-polylysine copolymer product was obtained, 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), and then iodobutane was added in a 4-fold excess of the lysine structural unit, and 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 with 0.10 mol / L NaCl solution for 24 hours, and then dialyzed with deionized water for another 24 hours. After freeze-drying, the nylon 1212-polylysine copolymer product with tributyl ammonium salt was obtained, which was 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), and then iodine hexane was added in a 4-fold excess of the lysine structural unit, and reacted 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 with 0.10 mol / L NaCl solution for 24 hours, and then dialyzed with deionized water for another 24 hours. After freeze-drying, the trihexyl ammonium salt-treated nylon 1212-polylysine copolymer product was obtained, named PAL 4000 -N(C6H 13 )3.

[0058] Example 5

[0059] On the basis of Example 1, 0.5 mol of 1H-pyrazole-1-carboxamidine hydrochloride and 0.5 mol of potassium carbonate were mixed in equal molar amounts and added to an aqueous solution of the product of Example 1 at a concentration of 2 wt% to obtain a mixed solution. After the mixed solution was replaced with nitrogen three times, it was stirred and heated at 55°C for 12 h (150 r / min), and 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 guanidinized nylon 1212-polylysine copolymer product, named PAL 4000 -CN3H4.

[0060] Example 6

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

[0062] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 30:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the nylon 1212-polylysine copolymer containing Boc protective group was obtained by post-treatment using ether precipitation, washing three times and vacuum drying. The copolymer was then dissolved in 4 mL of trifluoroacetic acid, stirred at room temperature for 12 hours, acid-lyzed, filtered and freeze-dried 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), and then iodoethane was added in a 4-fold excess of the lysine structural unit, and 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 was first dialyzed with 0.10 mol / L NaCl solution for 24 hours, and then dialyzed with deionized water for another 24 hours. After freeze-drying, the triethyl quaternary ammonium salt of nylon 1212-polylysine copolymer product was obtained, named PAL 6000 -N(C2H5)3.

[0065] Example 8

[0066] On the basis of Example 6, 0.5 mol of 1H-pyrazole-1-carboxamidine hydrochloride and 0.5 mol of potassium carbonate were mixed in equal molar amounts and added to an aqueous solution of the product of Example 6 at a concentration of 2 wt% to obtain a mixed solution. After the mixed solution was replaced with nitrogen three times, it was stirred and heated at 55°C for 12 h (150 r / min), and 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 guanidinized nylon 1212-polylysine copolymer product, named PAL 6000 -CN3H4.

[0067] Example 9

[0068] The diamine and the dibasic acid were weighed according to the molar ratio of dodecanediamine to dodecanedioic acid of 1.1:1, and condensed at high temperature to obtain a diamino-terminated nylon 1212 macroinitiator with a theoretical weight average molecular weight of 3500 g / mol, and the actual measured value was 3482 g / mol.

[0069] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 30:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the nylon 1212-polylysine copolymer containing Boc protective group was obtained by post-treatment using ether precipitation, washing three times and vacuum drying. The copolymer was then dissolved in 4 mL of trifluoroacetic acid, stirred at room temperature for 12 hours, acid-lyzed, filtered and freeze-dried 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), and then iodomethane was added in an excess of 4 times the amount of the lysine structural unit, and 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 was first dialyzed with 0.10 mol / L NaCl solution for 24 hours, and then dialyzed with deionized water for another 24 hours. After freeze-drying, a trimethyl ammonium salt-containing nylon 1212-polylysine copolymer product was obtained, named PAL 8000 -N(CH3)3.

[0072] Embodiment 11

[0073] On the basis of Example 9, 0.5 mol of 1H-pyrazole-1-carboxamidine hydrochloride and 0.5 mol of potassium carbonate were mixed in equal molar amounts and added to an aqueous solution of the product of Example 6 at a concentration of 2 wt% to obtain a mixed solution. After the mixed solution was replaced with nitrogen three times, it was stirred and heated at 55°C for 12 h (150 r / min), and 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 guanidinized nylon 1212-polylysine copolymer product, named PAL 8000 -CN3H4.

[0074] Example 12

[0075] The diamine and the dibasic acid were weighed according to the molar ratio of dodecanediamine to dodecanedioic acid of 1.5:1, and condensed at high temperature to obtain a diamino-terminated nylon 1212 macroinitiator with a theoretical weight average molecular weight of 1000 g / mol, and the actual measured value was 975 g / mol.

[0076] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 100:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the post-treatment was ether precipitation, washing three times and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protective group. A certain amount of amino product obtained after acid hydrolysis was dissolved in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), and then iodomethane was added in an excess of 4 times the lysine structural unit, and 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, first dialyzed with 0.10mol / L NaCl solution for 24 hours, and then dialyzed with deionized water for another 24 hours. After freeze-drying, a trimethyl quaternary ammonium salt nylon 1212-polylysine copolymer product with a number average molecular weight of 12000 was obtained, named PAL 12000 -N(CH3)3.

[0077] Embodiment 13

[0078] The diamine and the dibasic acid were weighed according to the molar ratio of dodecanediamine to dodecanedioic acid of 1.5:1, and condensed at high temperature to obtain a diamino-terminated nylon 1212 macroinitiator with a theoretical weight average molecular weight of 1000 g / mol, and the actual measured value was 975 g / mol.

[0079] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 100:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the post-treatment was ether precipitation, washing three times and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protective group. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2wt% solution, and 0.5mol of 1H-pyrazole-1-carboxamidine hydrochloride and 0.5mol of potassium carbonate were added. After nitrogen was replaced three times, the reaction was stirred and heated at 55°C for 12h (150r / min). The dialyzed product was concentrated and freeze-dried to obtain a guanidine nylon 1212-polylysine copolymer product, named PAL. 12000 -CN3H4.

[0080] Embodiment 14

[0081] The diamine and the dibasic acid were weighed according to the molar ratio of dodecanediamine to dodecanedioic acid of 1.5:1, and condensed at high temperature to obtain a diamino-terminated nylon 1212 macroinitiator with a theoretical weight average molecular weight of 1000 g / mol, and the actual measured value was 975 g / mol.

[0082] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 150:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the post-treatment was ether precipitation, washing three times and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protective group. A certain amount of amino product obtained after acid hydrolysis was dissolved in a mixed solution of N,N-dimethylformamide and water (volume ratio 1:1), and then iodomethane was added in an excess of 4 times the lysine structural unit, and reacted at 30°C for 24 hours. The reaction solution was directly transferred to a dialysis bag with a molecular weight cutoff of 3500, first dialyzed with 0.10mol / L NaCl solution for 24 hours, and then dialyzed with deionized water for another 24 hours. After freeze-drying, a trimethyl quaternary ammonium salt nylon 1212-polylysine copolymer product with a number average molecular weight of 16000 was obtained, named PAL 16000 -N(CH3)3.

[0083] Embodiment 15

[0084] The diamine and the dibasic acid were weighed according to the molar ratio of dodecanediamine to dodecanedioic acid of 1.5:1, and condensed at high temperature to obtain a diamino-terminated nylon 1212 macroinitiator with a theoretical weight average molecular weight of 1000 g / mol, and the actual measured value was 975 g / mol.

[0085] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1212 initiator of 150:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the post-treatment was ether precipitation, washing three times and vacuum drying to obtain nylon 1212-polylysine copolymer containing Boc protective group. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2wt% solution, and 0.5mol of 1H-pyrazole-1-carboxamidine hydrochloride and 0.5mol of potassium carbonate were added. After nitrogen was replaced three times, the reaction was stirred and heated at 55°C for 12h (150r / min). The dialyzed product was concentrated and freeze-dried to obtain a guanidine 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 the dibasic acid were weighed according to the molar ratio of 1.5:1 between octadecanoic acid and dodecanediamine, and condensed at high temperature to obtain a diamino-terminated nylon 1218 macroinitiator with a theoretical weight average molecular weight of 1000 g / mol, and the actual measured value was 1015 g / mol.

[0088] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 1218 initiator of 150:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the nylon 1018-polylysine copolymer containing Boc protective group was obtained by post-treatment using ether precipitation, washing three times and vacuum drying. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2wt% solution, 0.5mol of 1H-pyrazole-1-carboxamidine hydrochloride and 0.5mol of potassium carbonate were added, and the nitrogen was replaced three times, and the reaction was stirred and heated at 55°C for 12h (150r / min). The dialyzed product was concentrated and freeze-dried to obtain a guanidine nylon 1218-polylysine copolymer product with a number average molecular weight of 16000.

[0089] Comparative Example 2

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

[0091] According to the molar ratio of Boc-L-lysine anhydride monomer to diamino-terminated nylon 66 initiator of 150:1, the reaction was carried out at room temperature under nitrogen for 6 hours, and the nylon 66-polylysine copolymer containing Boc protective group was obtained by post-treatment using ether precipitation, washing three times and vacuum drying. The crude product obtained after acid hydrolysis was dissolved in water to prepare a 2wt% solution, 0.5mol of 1H-pyrazole-1-carboxamidine hydrochloride and 0.5mol of potassium carbonate were added, and the nitrogen was replaced three times, and the reaction was stirred and heated at 55°C for 12h (150r / min). The dialyzed product was concentrated and freeze-dried to obtain a guanidine 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, Germany.

[0094] Comparative Example 4

[0095] Arkema 7033SA01 medical grade elastomer material.

[0096] Comparative Example 5

[0097] Take 10g of polyhexamethylene biguanide hydrochloride (number average molecular weight is 241) and 990g of nylon 12 elastomer ( 7033SA01, melting point 174°C), after being uniformly mixed in a high-speed stirrer, melt-extruded in a twin-screw extruder, the extrusion temperature is 200°C, the screw speed is 130rpm, the material residence time is 1.5min, and after melt-extruded, a guanidine-modified antibacterial nylon 12 elastomer is obtained.

[0098] Comparative Example 6

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

[0100] Antibacterial effect test:

[0101] The antibacterial effect test was carried out according to the method of China's national standard GB / T 31402-2015 "Test Method for Antibacterial Performance of Plastic Surfaces", and the sample size and culture conditions were adjusted according to the actual situation. The specific operation was as follows: The permanent antibacterial nylon 1212 materials prepared in the above Examples 1-15 and the nylon 12 and its elastomer materials prepared in Comparative Examples 1-6 were pressed into 1 cm×1 cm square sheets respectively, irradiated under ultraviolet light for 30 minutes for sterilization, and then the prepared bacterial solution was dripped on the sheet, covered with PE film and incubated at 37°C for 6 hours. Ultrasonication for 3 minutes, diluted 100 times and placed on a solid culture medium for 24 hours at 37°C. The conventional nylon 6 material obtained in Comparative Examples 1-2 was used as the control group. The bacteria used for testing are Staphylococcus aureus (S. aureus) ATCC6538 and Escherichia coli (E. coli) ATCC25922. The results are shown in Table 1, which shows the antibacterial test results of the antibacterial nylon materials of Examples 1 to 15 and Comparative Examples 1 to 6. Figure 2 As shown, Figure 2 This is a test chart of the antibacterial effect of the antibacterial nylon 1212 material prepared in Comparative Example 2 and Example 15 on Staphylococcus aureus.

[0102] Table 1

[0103]

[0104]

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

[0106] Long-term antibacterial effect test:

[0107] The square sheets prepared from the above 9 embodiments and comparative examples 3-4 containing trimethyl quaternary ammonium salt and guanidine were immersed in water at 37°C for one month, and then the long-term antibacterial properties were tested according to the above test method. The above antibacterial test results are shown in Table 2, which shows the long-term antibacterial test results of the antibacterial nylon materials of the embodiments and comparative examples 3 to 4.

[0108] Table 2

[0109]

[0110] It can be seen from the test results in Table 2 that the antibacterial nylon material provided by the present invention has a long-lasting antibacterial effect, and the sterilization rate is still more than 95% after soaking for 1 month. When an organic guanidine salt or nano zirconium phosphate silver antibacterial agent is introduced and combined with a nylon elastomer, the antibacterial persistence of the obtained material after soaking is significantly deteriorated. It can be seen that the elastomeric material provided by the present invention has excellent antibacterial persistence. Different from the short antibacterial activity and easy loss of simple antibacterial agent composite systems, and the unstable antibacterial performance and molecular weight dependence of simple polymers / copolymers based on lysine, the series of permanent long carbon chain antibacterial nylon materials provided by the present invention can obtain relatively stable antibacterial properties by regulating the molecular weight of the nylon 1212 macromolecular initiator and its initiation ratio with the lysine internal anhydride monomer. It is speculated that the alternating chain segments derived from the nylon 1212 macromolecular initiator in the final structure can effectively block the positively charged polylysine units, and have size matching with the existence of microorganisms such as bacteria. The two work together to achieve the excellent synergistic long-term antibacterial effect of the structure described in the present invention. A nylon initiator chain length that is too short, such as PA66, will cause too much positive charge from the polylysine unit to accumulate on the material surface, and the electrostatic repulsion between adjacent units and adjacent chain segments will lead to a decrease in antibacterial activity; conversely, an initiator carbon chain length or molecular weight that is too long, such as choosing nylon 1218, will cause the positive charge distribution of the polylysine unit used for antibacterial purposes on the material surface to be too low, resulting in low bactericidal efficiency.

[0111] Mechanical properties test:

[0112] The antibacterial nylon materials prepared in the above-mentioned Examples 12 to 15 and Comparative Examples 1 to 4 were respectively injection molded into 40 mm × 4 mm × 2 mm strips, and mechanical property tests were performed. The results are shown in Table 3. Table 3 shows the mechanical property test results of the antibacterial nylon materials in Examples 12 to 15 and Comparative Examples 1 to 2.

[0113] Table 3

[0114]

[0115] As shown in Tables 1 to 2 and 3, the permanent antibacterial nylon 1212 material of the present application not only has a significant antibacterial effect ( Figure 2 ), especially the long-term antibacterial effect is much stronger than the antibacterial composite materials of comparative examples 1-2 and the commercially available nylon and its elastomer without antibacterial effect (see comparative examples 3-4). At the same time, the mechanical properties of the antibacterial nylon 1212 material can be adjusted by changing the feed ratio of the diamino-terminated nylon 1212 macroinitiator hard segment and the polylysine soft segment, and the mechanical properties equivalent to those of the nylon elastomer material in comparative example 4 can be obtained. In contrast, the mechanical properties of comparative examples 5-6 are significantly reduced after the antibacterial components are compounded, which affects the subsequent processing and use.

[0116] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A permanent antibacterial long carbon chain nylon polymer, characterized in that: It includes diamino-terminated nylon 1212 prepolymer units and lysine internal anhydride monomer units; The diamino-terminated nylon 1212 prepolymer unit has a structure of formula Ia; The n represents the number of repetitions of the chain link in which it is located; The lysine anhydride monomer unit has a structure of formula Ib; Wherein, R1, R2 and R3 are independently selected from hydrogen, substituted or unsubstituted C1 to C 16 One of the alkyl groups; or, the R1, R2 and R3 and the N to which they are connected together constitute a substituted or unsubstituted guanidine group; The m represents the number of repetitions of the link in which it is located.

2. The permanent antibacterial long carbon chain nylon polymer according to claim 1, characterized in that: The diamino-terminated nylon 1212 prepolymer unit is derived from a diamino-terminated nylon 1212 prepolymer monomer having a weight average molecular weight of 600 g / mol to 20,000 g / mol.

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

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

5. The permanent antibacterial long carbon chain nylon polymer according to claim 1, characterized in that: The molar ratio of the diamino-terminated nylon 1212 prepolymer unit to the polymer is 0.1 to 0.8; The molar ratio of the lysine anhydride monomer unit to the polymer is 0.2 to 0.

9.

6. The permanent antibacterial long carbon chain nylon polymer according to claim 5, characterized in that: The molar ratio of the diamino-terminated nylon 1212 prepolymer unit to the polymer is 0.2 to 0.4; The molar ratio of the lysine anhydride monomer unit to the polymer is 0.6 to 0.

8.

7. The permanent antibacterial long carbon chain nylon polymer according to claim 1, characterized in that: Said 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; Alternatively, the R1, R2 and R3 and the N to which they are connected together constitute a substituted or unsubstituted guanidine group.

8. A method for preparing the permanent antibacterial long carbon chain nylon polymer according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1) reacting a diamino-terminated nylon 1212 prepolymer monomer and a lysine internal anhydride monomer; The diamino-terminated nylon 1212 prepolymer monomer has a structure of formula II; The lysine internal anhydride monomer has a structure of formula III; Wherein, the R is a protecting group; S2) After removing the protecting group from the product obtained in step S1), an alkylation reaction or a guanidation reaction is performed to obtain a permanent antibacterial long carbon chain nylon polymer.

9. The preparation method according to claim 8, characterized in that: In step S1), the reaction temperature is 25°C to 50°C, and the reaction time is 2h to 24h.

10. A product, characterized in that At least a part of the polymer is obtained from the permanent antibacterial long carbon chain nylon polymer described in any one of claims 1 to 7 and optional additional materials.

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