An antibacterial nylon 6 material, its preparation method, its uses, and its products.

Abstract

An antibacterial nylon 6 material, its preparation method, and its application are disclosed. The antibacterial nylon 6 material has the structure shown in formula (I), wherein each R1 group and each R2 group is independently selected from C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups, or the R1 and R2 groups on the same nitrogen atom together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle; each R3 group is independently selected from hydrogen (H), C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups; x is in the range of 0.02-0.30; y is in the range of 0.70-0.98, and x+y=1. The antibacterial nylon 6 material has a broad-spectrum and highly effective antibacterial effect with long-lasting antibacterial action. As a public health material, it can be widely used in textiles, daily necessities, building materials, packaging materials, and various panels.

Description

Technical Field

[0001] This application relates to the technical field of antibacterial polymer materials, specifically to an antibacterial nylon 6 material, its preparation method, and its application. Prior Technology

[0002] Microorganisms in nature are incredibly diverse. In our daily lives, microorganisms are inextricably linked to us, while some bacteria, fungi, and viruses, as pathogens, seriously endanger human health and even life. For example, highly pathogenic avian influenza virus (H5N1), tuberculosis, SARS, and the novel coronavirus (2019-nCoV) are all caused by the spread of bacteria or microorganisms. After experiencing these devastating epidemics, people are increasingly concerned about the harm bacteria or microorganisms pose to their own health and living environment, and are demanding higher quality and functionality from the products they use. Therefore, the development of novel antimicrobial materials has become particularly important. Antimicrobial polymers can inhibit and kill bacteria, fungi, and other microorganisms attached to them, and have been widely used in hygiene, medical, and environmental protection fields.

[0003] Polycaprolactam (commonly known as nylon) possesses excellent properties such as light weight, high strength, wear resistance, resistance to weak acids, weak alkalis, and some organic solvents, and ease of molding and processing, making it widely used in fibers, engineering plastics, and films. However, nylon 6 (PA-6) contains highly polar amide groups in its molecular chain, which readily form hydrogen bonds with water molecules. This allows the product to easily absorb moisture from the environment, providing a favorable breeding ground for bacteria and fungi. Nylon 6 materials are almost ubiquitous in our daily lives; therefore, developing nylon 6 materials with antibacterial properties can effectively reduce or prevent bacterial infection and transmission, which is of great significance for improving the living environment and reducing disease.

[0004] Currently, commercially available antibacterial nylon 6 materials are mainly prepared by blending polycaprolactam with small molecule antibacterial agents, as shown in CN107652669, CN107793748, and CN108047709. However, these materials have many problems in terms of safety, environmental friendliness, and the high efficiency and durability of antibacterial activity.

[0005] Therefore, it is of great significance to develop novel antibacterial nylon 6 materials that are environmentally friendly and have long-lasting and efficient antibacterial properties. Summary of the Invention

[0006] The purpose of this application is to provide a novel nylon 6 material with antibacterial function, its preparation method and application. This nylon 6 material overcomes the defects of antibacterial nylon 6 materials obtained by blending, such as poor antibacterial durability and low stability. Moreover, it is low in cost, simple in preparation process, and suitable for large-scale production.

[0007] To achieve the above objectives, in one aspect, this application provides an antibacterial nylon 6 material having the structure shown in formula (I): (I) in,

[0008] Each R1 group and each R2 group is independently selected from C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups, or the R1 and R2 groups on the same nitrogen atom together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle;

[0009] Each R3 group is independently selected from hydrogen (H), C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups; and

[0010] x and y respectively represent the terms in equation (I) that have The molar ratio of repeating units in the structure to the total repeating units and having The molar proportion of repeating units in the structure to the total repeating units, where x is in the range of 0.02-0.30; y is in the range of 0.70-0.98, and x+y=1;

[0011] The term "substituted" means that the group is replaced by one or more substituents, which are C1-18 straight-chain or branched alkyl groups.

[0012] On the other hand, this application provides a nylon 6 composition comprising 70 wt% to less than 100 wt% of an antibacterial nylon 6 material according to this application and 0-30 wt% of at least one material different from the antibacterial nylon 6 material containing... Repeating units of the structure and / or having Polymers of repeating structural units, wherein groups R1, R2, and R3 are as defined above.

[0013] Furthermore, this application provides a method for preparing an antibacterial nylon 6 material, comprising the following steps:

[0014] 1) Provide a cyclic lysine monomer having the structure shown in formula (II) below, (II),

[0015] The R1 and R2 groups are independently selected from C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups, or the R1 and R2 groups together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle;

[0016] 2) The cyclic lysine monomer and caprolactam monomer are ring-opened polymerized at a molar ratio of 2:98 to 30:70 to obtain a copolymer having the structure shown in formula (III). (III),

[0017] 3) React the copolymer with a halide having the structure shown in formula (IV), R 3-Hal (IV),

[0018] The R3 group is selected from hydrogen (H), C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups.

[0019] Hal represents halogen.

[0020] An antibacterial nylon 6 material with the structure shown in formula (I) was obtained. (I),

[0021] The term "substituted" means that the group is replaced by one or more substituents, which are C1-18 straight-chain or branched alkyl groups.

[0022] The antibacterial nylon 6 material of this application has a broad-spectrum and highly effective antibacterial effect, and good antibacterial durability and stability. As a public health material, it can be widely used in textiles, daily necessities, building materials, packaging materials and various panels, etc. Moreover, it is inexpensive, has a simple preparation process, and is easy to mass-produce.

[0023] In another aspect, this application provides an article comprising the antibacterial nylon 6 material of this application, the nylon 6 composition of this application, or the antibacterial nylon 6 material prepared by the method of this application.

[0024] Preferably, the article is selected from textiles, daily necessities, building materials, packaging materials, and panels.

[0025] Other features and advantages of this application will be described in detail in the following detailed description section. Simple Explanation of the Diagram

[0026] The accompanying drawings are provided to further illustrate the present application and form part of the specification. They are used together with the following detailed description to explain the present application, but do not constitute a limitation thereof. In the drawings: Figure 1 shows a schematic diagram of a synthetic route for the antibacterial nylon 6 material according to this application; Figure 2 shows the NMR spectrum of the copolymer of dimethyl-protected cyclic lysine monomer and caprolactam monomer obtained in Example 1; Figures 3-7 show the DSC melting point test results of the antibacterial nylon 6 materials obtained in Examples 1-5, respectively; and Figures 8A and 8B show photographs illustrating the antibacterial effects of nylon 6 materials prepared in Comparative Example 1 and Example 5 against Staphylococcus aureus, respectively. Implementation

[0027] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0028] Any specific numerical values ​​disclosed herein (including the endpoints of numerical ranges) are not limited to their exact values, but should be understood to also include values ​​close to the exact value, such as all possible values ​​within ±5% of the exact value. Furthermore, with respect to the disclosed numerical ranges, one or more new numerical ranges can be obtained by arbitrarily combining the endpoint values ​​of the range, the endpoint values ​​with specific point values ​​within the range, and the specific point values ​​themselves; these new numerical ranges should also be considered as specifically disclosed herein.

[0029] Unless otherwise stated, the terms used herein have the same meaning as commonly understood by those skilled in the art, and if a term is defined herein and its definition differs from the common understanding in the art, the definition herein shall prevail.

[0030] In this application, the term "substituted" means that the group is substituted by one or more substituents, which are C1-18 straight-chain or branched alkyl groups, preferably C1-12 straight-chain or branched alkyl groups, and more preferably C1-6 straight-chain or branched alkyl groups.

[0031] In this application, except where expressly stated, any matters or issues not mentioned herein shall apply directly to those known in the art without any modification. Furthermore, any implementation described herein may be freely combined with one or more other implementations described herein, and the resulting technical solutions or concepts shall be considered part of the original disclosure or original record of this invention, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider such combination to be clearly unreasonable.

[0032] All patent and non-patent literature mentioned in this article, including but not limited to textbooks and journal articles, are incorporated in full by way of citation.

[0033] As described above, in a first aspect, this application provides an antibacterial nylon 6 material having the structure shown in formula (I): (I) in,

[0034] Each R1 group and each R2 group are independently selected from C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups, or the R1 and R2 groups on the same nitrogen atom together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle;

[0035] Each R3 group is independently selected from hydrogen (H), C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups; and

[0036] x and y respectively represent the terms in equation (I) that have The molar ratio of repeating units in the structure to the total repeating units and having The molar ratio of repeating units in the structure to the total repeating units, where x is in the range of 0.02-0.30; y is in the range of 0.70-0.98, and x+y=1.

[0037] In a preferred embodiment, each R1 group and each R2 group are independently selected from C1-12 straight-chain or branched aliphatic hydrocarbon groups (e.g., C1-8 straight-chain or branched aliphatic hydrocarbon groups, C1-6 straight-chain or branched aliphatic hydrocarbon groups, C1-4 straight-chain or branched aliphatic hydrocarbon groups, the aliphatic hydrocarbon group being, for example, alkyl or alkenyl, preferably alkyl), substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl and substituted or unsubstituted C7-16 aralkyl, or R1 and R2 groups on the same nitrogen atom together with the attached N atom to form a 5-6 member saturated or unsaturated heterocycle; and each R3 group is independently selected from hydrogen (H), C1-12 straight-chain or branched aliphatic hydrocarbon groups (e.g., C1-8 straight-chain or branched aliphatic hydrocarbon groups, C1-6 straight-chain or branched aliphatic hydrocarbon groups, C1-4 straight-chain or branched aliphatic hydrocarbon groups, C1-12 ... 1-4 Straight-chain or branched aliphatic hydrocarbon groups, said aliphatic hydrocarbon groups being, for example, alkyl or alkenyl (preferably alkyl), substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl groups, and substituted or unsubstituted C7-16 aralkyl groups.

[0038] In a further preferred embodiment, each R1 group and each R2 group are independently selected from methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, allyl, phenyl, and benzyl, or the R1 and R2 groups on the same nitrogen atom together with the attached N atom form a tetrahydropyrrole or hexahydropyridyl; and each R3 group is independently selected from hydrogen (H), methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, cyclohexyl, phenyl, and benzyl.

[0039] In a further preferred embodiment, all R1 groups and R2 groups are identical and selected from methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, allyl, and benzyl, or the R1 and R2 groups on the same nitrogen atom together with the attached N atom form a tetrahydropyrrole or hexahydropyridyl; and all R3 groups are identical and selected from hydrogen (H), methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, cyclohexyl, and benzyl.

[0040] In a particularly preferred embodiment, all R1 and R2 groups are identical and selected from methyl, ethyl, propyl, butyl, dodecyl, allyl, and benzyl, especially ethyl, propyl, butyl, and benzyl, or the R1 and R2 groups on the same nitrogen atom together with the attached N atom form a hexahydropyridyl group; and all R3 groups are identical and selected from hydrogen (H), ethyl, cyclohexyl, and benzyl, especially ethyl.

[0041] In a preferred embodiment, x in formula (I) is in the range of 0.03-0.25, more preferably 0.04-0.20, for example, in the range of 0.08-0.20, 0.12-0.20 or 0.16-0.20; y is in the range of 0.75-0.97, more preferably 0.80-0.96, for example, in the range of 0.80-0.92, 0.88-0.80 or 0.84-0.80, and x+y=1.

[0042] In a preferred embodiment, the total number of repeating units in the antibacterial nylon 6 material shown in formula (I) is in the range of 10-2500, preferably 20-1000, and more preferably 20-500.

[0043] In a preferred embodiment, the antibacterial nylon 6 material has a weight average molecular weight of 2,000-500,000, preferably 5,000-200,000, and more preferably 5,000-100,000.

[0044] In a second aspect, this application provides a nylon 6 composition comprising 70 wt% to less than 100 wt% of an antimicrobial nylon 6 material according to this application and 0-30 wt% of at least one material different from the antimicrobial nylon 6 material comprising having Repeating units of the structure and / or having Polymers composed of repeating structural units, wherein groups R1, R2, and R3 are as defined above.

[0045] In a preferred embodiment, the nylon 6 composition comprises 80 wt% to less than 100 wt%, more preferably 90 wt% to less than 100 wt%, such as 91 wt%, 92 wt%, 93 wt%, 94 wt%, 95 wt%, 96 wt%, 97 wt%, 98 wt%, 99 wt%, of the antimicrobial nylon 6 material according to the present application, and at least one polymer different from the antimicrobial nylon 6 material, comprising 80 wt% to less than 100 wt%, more preferably greater than 0 wt% to 10 wt%, such as 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%.

[0046] In some specific embodiments, the polymer, which is different from the antibacterial nylon 6 material, has a structure similar to that of formula (I), except that x is outside the range of 0.02-0.30, y is outside the range of 0.70-0.98, and x+y=1.

[0047] In a preferred embodiment, the nylon 6 composition of this application further comprises 0-30 wt%, preferably 0-20 wt%, more preferably 0-10 wt%, such as 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, additives selected from reinforcing agents, fillers, toughening agents, plasticizers, flame retardants, colorants, fluorescent whitening agents, light stabilizers, antioxidants, heat stabilizers, lubricants, mold release agents, and combinations thereof.

[0048] The additives suitable for the compositions of this application can be various conventional additives used in the production and processing of nylon, and this application does not impose strict limitations on them. For example, the fillers suitable for the compositions of this application can be those commonly used in the art, including but not limited to activated calcium carbonate, talc, wollastonite, mica, etc.; the antioxidants suitable for the compositions of this application can be those commonly used in the art, including but not limited to phenolic antioxidants, phosphite antioxidants, etc.

[0049] From the perspective of cooperating manufacturers, this application provides a method for preparing antibacterial nylon 6 material, comprising the following steps:

[0050] 1) Provide a cyclic lysine monomer having the structure shown in formula (II) below, (II),

[0051] The R1 and R2 groups are independently selected from C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups, or the R1 and R2 groups together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle;

[0052] 2) The cyclic lysine monomer and caprolactam monomer are ring-opened polymerized at a molar ratio of 2:98 to 30:70 to obtain a copolymer having the structure shown in formula (III). (III),

[0053] 3) React the copolymer with a halide having the structure shown in formula (IV),

[0054] R 3-Hal (IV),

[0055] The R3 group is selected from hydrogen (H), C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups.

[0056] Hal represents halogen.

[0057] An antibacterial nylon 6 material with the structure shown in formula (I) was obtained. (I).

[0058] Figure 1 shows a schematic diagram of a synthetic route for preparing the antibacterial nylon 6 material according to this application.

[0059] In a preferred embodiment, R1 and R2 groups are independently selected from C1-12 straight-chain or branched aliphatic hydrocarbon groups (e.g., C1-8 straight-chain or branched aliphatic hydrocarbon groups, C1-6 straight-chain or branched aliphatic hydrocarbon groups, C1-4 straight-chain or branched aliphatic hydrocarbon groups, wherein the aliphatic hydrocarbon group is, for example, alkyl or alkenyl, preferably alkyl), substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl and substituted or unsubstituted C7-16 aralkyl groups, or R1 and R2 groups together with the attached N atom form a 5-6 member saturated or unsaturated heterocycle; R3 group is selected from hydrogen (H), C1-12 straight-chain or branched aliphatic hydrocarbon groups (e.g., C1-8 straight-chain or branched aliphatic hydrocarbon groups, C1-6 straight-chain or branched aliphatic hydrocarbon groups, C1-4 straight-chain or branched aliphatic hydrocarbon groups, wherein the aliphatic hydrocarbon group is, for example, alkyl or alkenyl, preferably alkyl), substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, C1-12 straight-chain or branched aliphatic hydrocarbon groups, C1-12 straight-chain or branched aliphatic hydrocarbon groups, C1-12 straight-chain or branched aliphatic hydrocarbon groups, C1-12 straight-chain or branched aliphatic hydrocarbon groups, C1-12 straight-chain or branched aliphatic hydrocarbon groups, wherein the aliphatic hydrocarbon group is, for example, alkyl or alkenyl, preferably alkyl), substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, C1-12 straight-chain or branched aliphatic ... 3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl groups and substituted or unsubstituted C7-16 aralkyl groups; and Hal represents chlorine, bromine or iodine.

[0060] In a further preferred embodiment, R1 and R2 groups are independently selected from methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, allyl, phenyl, and benzyl, or R1 and R2 groups together with the attached N atom form tetrahydropyrrole or hexahydropyridyl; R3 group is selected from hydrogen (H), methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, cyclohexyl, phenyl, and benzyl; and Hal represents chlorine, bromine, or iodine.

[0061] In a further preferred embodiment, R1 and R2 groups are identical and selected from methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, allyl, and benzyl, or R1 and R2 groups together with the attached N atom form tetrahydropyrrole or hexahydropyridyl; R3 group is selected from hydrogen (H), methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl, cyclohexyl, and benzyl; and Hal represents chlorine, bromine, or iodine.

[0062] In a particularly preferred embodiment, R1 and R2 groups are identical and selected from methyl, ethyl, propyl, butyl, dodecyl, allyl, and benzyl, especially ethyl, propyl, butyl, and benzyl, or R1 and R2 groups together with the attached N atom form a hexahydropyridyl group; R3 group is selected from hydrogen (H), ethyl, cyclohexyl, and benzyl, especially ethyl; and Hal represents chlorine or bromine, preferably bromine.

[0063] In a preferred embodiment of the method of this application, the cyclic lysine monomer is provided in step 1) by protecting the primary amine group on the aminocaprolactam of formula (V) with a protecting group.

[0064] (V). For example, the protecting group can be the R1 and R2 groups defined above, which will not be described again here.

[0065] In a further preferred embodiment, step 1) is achieved by reacting the aminocaprolactam with a corresponding aldehyde and / or halogenated hydrocarbon having R1 and / or R2 groups, preferably by reacting the aminocaprolactam with a reagent selected from formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, benzyl chloride, 1,5-dibromopentane, allyl bromide, dodecyl bromide, or combinations thereof.

[0066] In some further preferred embodiments, the aminocaprolactam used in step 1) can be prepared from L-lysine acid salt by the following steps: i) methylating L-lysine acid salt to obtain methylated L-lysine acid, preferably using methanol as solvent and methylating agent, concentrated sulfuric acid as catalyst, and refluxing for 8-10 h to obtain methylated L-lysine acid; and ii) reacting the methylated L-lysine acid with an alkaline solution in methanol solvent to obtain aminocaprolactam, preferably reacting at room temperature for 10-12 h, and then concentrating and recrystallizing to obtain aminocaprolactam.

[0067] In a preferred embodiment, the molar ratio of the cyclic lysine monomer to the caprolactam monomer used in step 2) is 3:97 to 25:75, more preferably 4:96 to 20:80.

[0068] In a preferred embodiment, step 2) is carried out in the presence of a catalyst, preferably selected from carbene reagents, guanidine reagents, amidine reagents, phosphazene reagents, alkali metals, alkali metal oxides, alkali metal hydroxides, alkali metal hydrides, alkali metal alkoxides, alkaline earth metals, alkaline earth metal oxides, alkaline earth metal hydroxides, alkaline earth metal hydrides, alkaline earth metal alkoxides, or combinations thereof. More preferably, the catalyst is selected from sodium hydride, potassium hydride, phosphononitrile base (t-BuP 4), potassium terbutoxide, sodium methoxide, potassium methoxide, DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), TBD (1,5,7-triazabicyclo[4.4.0]dec-5-ene), sodium, potassium, or combinations thereof.

[0069] In a further preferred embodiment, the total amount of the cyclic lysine monomer and caprolactam monomer in step 2) is in a molar ratio to the catalyst of (10-50):1, preferably (10-30):1.

[0070] In a further preferred embodiment, the ring-opening polymerization in step 2) is carried out in the presence of an activator having the following structure;

[0071] R is selected from methyl, ethyl, phenyl, tributylphenyl and trifluoromethylphenyl.

[0072] More preferably, the total amount of the cyclic lysine monomer and caprolactam monomer in step 2) is in molar ratio to the activator as (10-50):1, preferably (10-30):1.

[0073] In a preferred embodiment, the reaction conditions for step 2) include: a polymerization reaction temperature of 140-180°C and a reaction time of 3-6 hours.

[0074] In a preferred embodiment, the halide with the structure shown in formula (IV) used in step 3) is selected from hydrochloric acid, iodomethane, bromoethane, bromobutane, bromohexane, bromocyclohexane, benzyl bromide, or combinations thereof, more preferably selected from hydrochloric acid, bromoethane, bromocyclohexane, benzyl bromide, or combinations thereof.

[0075] In a preferred embodiment, the reaction in step 3) is carried out in a solvent selected from methanol, ethanol, trifluoroethanol, benzyl alcohol, ethylene glycol, cyclohexanol, or combinations thereof, more preferably in a trifluoroethanol solvent. More preferably, the reaction conditions for step 3) include: a reaction temperature of 40-70°C and a reaction time of 10-12 h.

[0076] In some preferred embodiments, step 3) further includes precipitating the reaction product of the copolymer and the halide in ethyl acetate, centrifuging and drying to obtain the antibacterial nylon 6 material.

[0077] Fourthly, this application provides an article comprising the antibacterial nylon 6 material of this application, the nylon 6 composition of this application, or the antibacterial nylon 6 material prepared by the method of this application.

[0078] In some preferred embodiments, at least a portion of the article is made of the antibacterial nylon 6 material.

[0079] In a preferred embodiment, the article is selected from textiles, daily necessities, building materials, packaging materials and panels, such as masks, protective clothing, towels, carpets, cling film, bicycle handlebars, etc.

[0080] According to this application, the article or a portion thereof may be manufactured using the antibacterial nylon 6 material or the nylon 6 composition of this application by conventional means, such as 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, and will not be elaborated here.

[0081] Example

[0082] The present application will be further described below with reference to the embodiments, but this will not limit the present application in any way.

[0083] Unless otherwise stated, all reagents used in the following examples are commercially available products of analytical purity.

[0084] In the following examples and comparative examples, the NMR spectra of the obtained aminocaprolactam intermediate and nylon 6 material were measured using a Burker AV-300 liquid superconducting NMR spectrometer with a mixed solvent of deuterated dimethyl sulfoxide and trifluoroacetic acid at room temperature; the weight-average molecular weight was measured using a Waters 515 gel permeation chromatography system (Waters Corporation, USA) with hexafluoroisopropanol containing 0.02 mol / L sodium trifluoroacetate as the eluent at room temperature.

[0085] In the following examples and comparative examples, the melting point of the obtained nylon 6 material was measured using a differential scanning calorimeter (DSC) model Q2000 DSC7 from TA Instruments, Inc. The specific method is as follows: 5 mg of sample was weighed and placed in the sample cell of the DSC7 differential scanning calorimeter. The sample was heated from 25°C to 250°C at a heating rate of 10°C / min in a nitrogen flow of 50 ml / min. The melting point of the sample was then measured.

[0086] Example 1

[0087] (1) Preparation of aminocaprolactam

[0088] Weigh 546 g (3 mol) of L-lysine acid salt and 1.5 L of methanol into a 2 L three-necked flask. Add 176 mL (3.3 mol) of concentrated sulfuric acid (98%) dropwise using a constant pressure dropping funnel while stirring mechanically. After the concentrated sulfuric acid is added, the solution becomes clear. Transfer the solution to a 2 L single-necked flask and reflux for 8 h to obtain methylated lysine acid.

[0089] The methylated lysine was transferred to a 50 L reactor, and 28.5 L of methanol was added with continued mechanical stirring. A methanol solution of sodium hydroxide (480 g sodium hydroxide solution + 2 L methanol) was added dropwise, and the reaction was carried out at room temperature for 10–12 h. After concentration and recrystallization, aminocaprolactam was obtained with a yield of 80%, and its purity was 90% according to 1H NMR spectroscopy.

[0090] (2) Preparation of dimethyl-protected aminocaprolactam

[0091] 30 g (234 mmol) of the aminocaprolactam prepared in step (1) was weighed and dissolved in 500 ml of methanol. 42 g (514 mmol) of formaldehyde solution (37% by mass) and 3 g of 10% palladium on carbon were added, and the mixture was reacted under a hydrogen atmosphere for 24 h. After filtration, concentration, and recrystallization, dimethyl-protected aminocaprolactam was obtained with a yield of 92%, and its purity was 98% according to 1H NMR spectroscopy.

[0092] (3) Preparation of antibacterial nylon 6 materials

[0093] Weigh 0.5 g (3.2 mmol) of the dimethyl-protected aminocaprolactam prepared in step (2), 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0094] Dissolve in 100 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are shown in Figure 2: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0095] Based on the integral area ratio of positions f and h in Figure 2, the molar percentage of ε-lysine derivative copolymer units in the obtained copolymer was calculated to be approximately 4%. 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), a yield of 92%, a weight-average molecular weight of 8500, and a melting point of 210.6°C. Its DSC melting point test chart is shown in Figure 3. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material is approximately 4%.

[0096] Example 2

[0097] Weigh 2 g (12.8 mmol) of dimethyl-protected aminocaprolactam obtained in step (2) of Example 1, 18 g (0.16 mol) of caprolactam, and 0.54 g (3.5 mmol) of N-methylcaprolactam activator into a 50 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 0.14 g (3.5 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0098] Dissolve in 180 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0099] 4.2 g (38.4 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was then settled in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), with a yield of 95%, a weight average molecular weight of 10,000, and a melting point of 199.5 °C. Its DSC melting point test chart is shown in Figure 4. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material is approximately 8%.

[0100] Example 3

[0101] Weigh 3 g (19.2 mmol) of dimethyl-protected aminocaprolactam obtained in step (2) of Example 1, 17 g (0.15 mol) of caprolactam, and 0.74 g (3.4 mmol) of N-benzoylcaprolactam activator into a 50 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 0.14 g (3.4 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0102] Dissolve in 150 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0103] 6.3 g (57.6 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was then settled in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), with a yield of 90%, a weight-average molecular weight of 12000, and a melting point of 185.7 °C. Its DSC melting point is shown in Figure 5. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material is approximately 12%.

[0104] Example 4

[0105] Weigh 4 g (25.6 mmol) of dimethyl-protected aminocaprolactam obtained in step (2) of Example 1, 16 g (0.14 mol) of caprolactam, and 0.56 g (3.3 mmol) of N-acetylopeptylcaprolactam activator into a 50 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 0.13 g (3.3 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0106] Dissolve in 180 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0107] 8.4 g (77.8 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was then settled in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), with a yield of 89%, a weight-average molecular weight of 15,000, and a melting point of 176.3 °C. Its DSC melting point is shown in Figure 6. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material is approximately 16%.

[0108] Example 5

[0109] Weigh 5 g (32 mmol) of dimethyl-protected aminocaprolactam prepared in step (2) of Example 1, 15 g (0.13 mol) of caprolactam, and 0.87 g (3.2 mmol) of N-tert-butylbenzoylcaprolactam activator into a 50 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 0.13 g (3.3 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0110] Dissolve in 160 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0111] 10.5 g (96 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40 °C for 12 h. The reaction solution was then settled in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), with a yield of 85%, a weight-average molecular weight of 18,000, and a melting point of 167.5 °C. Its DSC melting point test chart is shown in Figure 7. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material is approximately 20%.

[0112] Example 6

[0113] Weigh 0.5 g (3.2 mmol) of dimethyl-protected aminocaprolactam obtained in step (2) of Example 1, 9.5 g (84 mmol) of caprolactam, and 0.48 g (1.7 mmol) of N-trifluoromethylbenzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0114] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0115] 100 ml of hydrochloric acid solution (6 M) was added to the remaining solution, and the reaction was carried out at room temperature for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), with a yield of 85%, a weight average molecular weight of 6000, and a melting point of 212.4 °C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0116] Example 7

[0117] Weigh 0.5 g (3.2 mmol) of dimethyl-protected aminocaprolactam prepared in step (2) of Example 1, 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0118] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0119] 15.6 g (96 mmol) of bromocyclohexane was added to the remaining solution and reacted in an oil bath at 40 °C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 95% yield, with a weight average molecular weight of 20,000 and a melting point of 208.6 °C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0120] Example 8

[0121] Weigh 0.5 g (3.2 mmol) of dimethyl-protected aminocaprolactam prepared in step (2) of Example 1, 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0122] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0123] 16.4 g (96 mmol) of benzyl bromide was added to the remaining solution and reacted in an oil bath at 40 °C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 98% yield, with a weight average molecular weight of 50,000 and a melting point of 206.3 °C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0124] Example 9

[0125] (1) Preparation of diethyl-protected aminocaprolactam

[0126] 30 g (234 mmol) of aminocaprolactam was weighed and dissolved in 500 ml of methanol. 56.6 g (514 mmol) of acetaldehyde solution (40% by mass) and 3 g of 10% palladium on carbon were added, and the mixture was reacted under hydrogen atmosphere for 24 h. After filtration, concentration, and recrystallization, diethyl-protected aminocaprolactam was obtained with a yield of 88%, and its purity was 95% according to 1H NMR spectroscopy.

[0127] (2) Preparation of antibacterial nylon 6 materials

[0128] Weigh 0.59 g (3.2 mmol) of diethyl-protected aminocaprolactam prepared in step (1), 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0129] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.75-3.63, 3.34-3.12, 2.78-2.62, 2.50-2.40, 1.61-1.28.

[0130] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 82% yield, with a weight average molecular weight of 13,000 and a melting point of 208.2°C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0131] Example 10

[0132] (1) Preparation of dipropyl-protected aminocaprolactam

[0133] 30 g (234 mmol) of aminocaprolactam was weighed and dissolved in 500 ml of methanol. 29.9 g (514 mmol) of propionaldehyde and 3 g of 10% palladium on carbon were added, and the mixture was reacted under hydrogen atmosphere for 24 h. After filtration, concentration, and recrystallization, dipropyl-protected aminocaprolactam was obtained with a yield of 89%, and its purity was 97% according to 1H NMR spectroscopy.

[0134] (2) Preparation of antibacterial nylon 6 materials

[0135] Weigh 0.68 g (3.2 mmol) of dipropyl-protected aminocaprolactam prepared in step (1), 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0136] Dissolve in 100 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.85-3.53, 3.30-3.10, 2.88-2.52, 2.40-2.28, 1.71-1.18.

[0137] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 93% yield, with a weight average molecular weight of 18,000 and a melting point of 201.7°C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0138] Example 11

[0139] (1) Preparation of dibutyl-protected aminocaprolactam

[0140] 30 g (234 mmol) of aminocaprolactam was weighed and dissolved in 500 ml of methanol. 37.1 g (514 mmol) of butyraldehyde and 3 g of 10% palladium on carbon were added, and the mixture was reacted under hydrogen atmosphere for 24 h. After filtration, concentration, and recrystallization, dibutyl-protected aminocaprolactam was obtained with a yield of 86%, and its purity was 96% according to 1H NMR spectroscopy.

[0141] (2) Preparation of antibacterial nylon 6 materials

[0142] Weigh 0.77 g (3.2 mmol) of the dibutyl-protected aminocaprolactam prepared in step (1), 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0143] Dissolve in 100 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.95-3.73, 3.30-3.10, 2.58-2.42, 2.30-2.10, 1.60-1.08.

[0144] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 86% yield, with a weight average molecular weight of 25,000 and a melting point of 201.1°C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0145] Example 12

[0146] (1) Preparation of dibenzyl-protected aminocaprolactam

[0147] 30 g (234 mmol) of aminocaprolactam was weighed and dissolved in 500 mL of acetonitrile. 56 mL (491 mmol) of benzyl chloride and 46.8 g (351 mmol) of potassium carbonate were added, and the mixture was stirred at 80 °C for 6 h. The solution was washed with 1 M HCl, extracted with dichloromethane, dried over anhydrous sodium sulfate, filtered, concentrated, and recrystallized to obtain dibenzyl-protected aminocaprolactam in 85% yield. The purity was 95% according to 1H NMR spectroscopy.

[0148] (2) Preparation of antibacterial nylon 6 materials

[0149] Weigh 0.99 g (3.2 mmol) of the dibenzyl-protected aminocaprolactam prepared in step (1), 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0150] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 7.35-7.12, 5.52-5.36, 3.75-3.63, 3.24-3.10, 2.51-2.38, 1.81-1.28.

[0151] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 93% yield, with a weight average molecular weight of 50,000 and a melting point of 196.5°C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0152] Example 13

[0153] (1) Preparation of N,N-hexahydropyridylaminocaprolactam

[0154] 30 g (234 mmol) of aminocaprolactam was weighed and dissolved in 500 ml of acetonitrile. 80.7 g (351 mmol) of 1,5-dibromopentane and 46.8 g (351 mmol) of potassium carbonate were added, and the mixture was stirred at 80 °C for 6 h. The solution was washed with 1 M HCl, extracted with dichloromethane, dried over anhydrous sodium sulfate, filtered, concentrated, and recrystallized to obtain N,N-hexahydropyridylaminocaprolactam in 75% yield. The purity was 90% according to 1H NMR spectroscopy.

[0155] (2) Preparation of antibacterial nylon 6 materials

[0156] Weigh 0.63 g (3.2 mmol) of N,N-hexahydropyridylaminocaprolactam, 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0157] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 5.53-5.31, 3.70-3.53, 3.32-3.12, 2.55-2.40, 1.61-1.18.

[0158] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 88% yield, with a weight average molecular weight of 20,000 and a melting point of 193.8°C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0159] Example 14

[0160] (1) Preparation of diallyl-protected aminocaprolactam

[0161] 30 g (234 mmol) of aminocaprolactam was weighed and dissolved in 500 mL of acetonitrile. 59.4 g (491 mmol) of allyl bromide and 46.8 g (351 mmol) of potassium carbonate were added, and the mixture was stirred at 80 °C for 6 h. The mixture was washed with 1 M HCl, extracted with dichloromethane, dried over anhydrous sodium sulfate, filtered, concentrated, and recrystallized to obtain diallyl-protected aminocaprolactam in 78% yield. The purity was 97% according to 1H NMR spectroscopy.

[0162] (2) Preparation of antibacterial nylon 6 materials

[0163] Weigh 0.67 g (3.2 mmol) diallyl-protected aminocaprolactam, 9.5 g (84 mmol) caprolactam, and 0.37 g (1.7 mmol) N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0164] Dissolve in 100 ml of trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 4.53-4.23, 3.95-3.73, 3.44-3.22, 2.53-2.40, 1.81-1.38.

[0165] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 92% yield, with a weight average molecular weight of 18,000 and a melting point of 200.3°C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0166] Example 15

[0167] (1) Preparation of docosyl-protected aminocaprolactam

[0168] 30 g (234 mmol) of aminocaprolactam was weighed and dissolved in 500 mL of acetonitrile. 122.4 g (491 mmol) of dodecyl bromide and 46.8 g (351 mmol) of potassium carbonate were added, and the mixture was stirred at 80 °C for 6 h. The solution was washed with 1 M HCl, extracted with dichloromethane, dried over anhydrous sodium sulfate, filtered, concentrated, and recrystallized to obtain docosyl-protected aminocaprolactam in 70% yield. The purity was 90% according to 1H NMR spectroscopy.

[0169] (2) Preparation of antibacterial nylon 6 materials

[0170] Weigh 1.49 g (3.2 mmol) of the docosyl-protected aminocaprolactam prepared in step (1), 9.5 g (84 mmol) of caprolactam, and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 70 mg (1.7 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0171] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.65-3.43, 3.24-3.02, 2.758-2.32, 2.20-2.06, 1.51-1.18.

[0172] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived antibacterial nylon 6 material with general formula (I), in 89% yield, with a weight average molecular weight of 80,000 and a melting point of 185.6°C. The molar percentage of ε-lysine derivative copolymer units in this antibacterial nylon 6 material was approximately 4%.

[0173] Compare with Example 1

[0174] 9.5 g (84 mmol) of caprolactam and 0.37 g (1.7 mmol) of N-benzoylcaprolactam activator were weighed into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, 70 mg (1.7 mmol) of sodium hydride was added. Under nitrogen protection, the mixture was reacted in an oil bath at 180°C for 6 h to obtain conventional nylon 6 material. The melting point was measured to be 222.3 °C.

[0175] Compare with Example 2

[0176] Weigh 0.25 g (1.6 mmol) of dimethyl-protected aminocaprolactam prepared in step (2) of Example 1, 36.2 g (320 mmol) of caprolactam, and 1.41 g (6.5 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 260 mg (6.5 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0177] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0178] 1 g (19.2 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived modified nylon 6 material with a yield of 98%, a weight average molecular weight of 50,000, and a melting point of 219.5°C. The molar percentage of ε-lysine derivative copolymer units in this modified nylon 6 material was approximately 0.5%.

[0179] Compare with Example 3

[0180] Weigh 15.6 g (100 mmol) of dimethyl-protected aminocaprolactam prepared in step (2) of Example 1, 11.3 g (100 mmol) of caprolactam, and 0.87 g (4 mmol) of N-benzoylcaprolactam activator into a 25 ml round-bottom flask. After evacuating the gas at 40°C for 30 min, add 160 mg (4 mmol) of sodium hydride. Under nitrogen protection, react in an oil bath at 180°C for 6 h.

[0181] Dissolve in 100 ml trifluoroethanol, take out a portion of the material for NMR characterization, and the results are as follows: 1H NMR (DMSO-d 6, 300 MHz) δ 3.70-3.61, 3.13-3.02, 2.76-2.72, 2.51-2.50, 1.81-1.18.

[0182] 65.3 g (600 mmol) of bromoethane was added to the remaining solution and reacted in an oil bath at 40°C for 12 h. The reaction solution was precipitated in ethyl acetate, centrifuged, and dried to obtain a cationic poly(ε-lysine)-derived modified nylon 6 material with a yield of 60% and a weight-average molecular weight of 13,500. This material was amorphous and its melting point was not determined. The molar percentage of ε-lysine derivative copolymer units in this modified nylon 6 material was approximately 40%.

[0183] Table 1. Structural characteristics of nylon 6 materials obtained in each embodiment and comparative example. Example number R 1 R 2 R 3 x y Example 1 methyl methyl Ethyl 0.04 0.96 Example 2 methyl methyl Ethyl 0.08 0.92 Example 3 methyl methyl Ethyl 0.12 0.88 Example 4 methyl methyl Ethyl 0.16 0.84 Example 5 methyl methyl Ethyl 0.20 0.8 Example 6 methyl methyl Hydrogen (H) 0.04 0.96 Example 7 methyl methyl Cyclohexyl 0.04 0.96 Example 8 methyl methyl benzyl 0.04 0.96 Example 9 Ethyl Ethyl Ethyl 0.04 0.96 Example 10 propyl propyl Ethyl 0.04 0.96 Example 11 Butyl Butyl Ethyl 0.04 0.96 Example 12 benzyl benzyl Ethyl 0.04 0.96 Example 13 Together with the attached N atom, it forms a hexahydropyridyl group. Ethyl 0.04 0.96 Example 14 Allyl Allyl Ethyl 0.04 0.96 Example 15 dodecyl dodecyl Ethyl 0.04 0.96 Compare with Example 1 - - - 0 1 Compare with Example 2 methyl methyl Ethyl 0.005 0.995 Compare with Example 3 methyl methyl Ethyl 0.4 0.6

[0184] Antibacterial effect test

[0185] The antibacterial effect was tested according to the method of Chinese National Standard GB / T 31402-2015, and the incubation time and temperature were adjusted according to the actual situation. The specific operation is as follows: The antibacterial nylon 6 materials prepared in Examples 1-15 and the nylon 6 materials prepared in Control Examples 1-3 were pressed into square thin slices of 0.75cm×0.75cm, sterilized by irradiation under ultraviolet light for 30min, and then the prepared bacterial solution was dropped onto the slices. After covering with PE film, the slices were incubated at 37℃ for 6h. After ultrasonic treatment for 3min, the slices were diluted 100 times and placed on solid culture medium for incubation at 37℃ for 20h. The conventional nylon 6 material obtained in Control Example 1 was used as the control group. The bacteria used for testing were Staphylococcus aureus (S. aureus) ATCC6538 and Escherichia coli (E. coli) ATCC25922. The test results are shown in Table 2.

[0186] The formula for calculating the antibacterial rate is as follows:

[0187] Mechanical performance testing

[0188] The antibacterial nylon 6 materials prepared in Examples 1-15 and the nylon 6 materials prepared in Comparative Examples 1-3 were injection molded into 40 mm × 4 mm × 2 mm specimens, and tensile properties were tested. The results are shown in Table 2.

[0189] Table 2. Antibacterial efficiency and tensile properties of nylon 6 materials obtained in the examples and control examples. Example number Antibacterial efficiency Tensile properties S. aureus anti bacterial count (%) E. coli anti- bacterial count (%) Tensile strength (MPa) Elongation at break (%) Example 1 32.8 26.4 75 19 Example 2 57.6 53.8 73 18 Example 3 68.3 65.7 72 16 Example 4 80.7 76.2 71 14 Example 5 96.8 90.5 70 13 Example 6 15.2 12.3 60 8 Example 7 28.5 21.6 71 19 Example 8 35.7 33.2 72 16 Example 9 66.8 45.4 71 20 Example 10 76.6 62.8 68 16 Example 11 62.3 29.7 68 18 Example 12 82.3 69.7 70 19 Example 13 95.7 89.2 73 12 Example 14 40.5 37.3 66 13 Example 15 60.2 54.9 67 15 Compare with Example 1 0 0 79 twenty one Compare with Example 2 3.2 1.2 77 20 Compare with Example 3 98.5 95.6 12 6

[0190] As shown in Table 2, the antibacterial nylon 6 material of this application has significant antibacterial effect and mechanical properties that are basically equivalent to those of conventional nylon 6 material. In contrast, the antibacterial properties of the nylon 6 material of Comparative Example 2 are insufficient, while the mechanical properties of the nylon 6 material of Comparative Example 3 are poor.

[0191] Figures 8A and 8B show comparative photographs of the antibacterial effects of the nylon 6 materials prepared in Comparative Example 1 and Example 5 against Staphylococcus aureus, where the spots represent surviving colonies. It is clearly evident from the figures that, compared to the conventional nylon 6 material prepared in Comparative Example 1, the antibacterial nylon 6 material of this application exhibits a significant inhibitory effect on Staphylococcus aureus.

[0192] The preferred embodiments of this application have been described in detail above. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solution of this application, and these simple modifications all fall within the protection scope of this application.

[0193] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, this application will not describe the various possible combinations separately.

[0194] Furthermore, various different embodiments of this application can be combined in any way, as long as they do not violate the spirit of this application, they should also be regarded as the content of this application.

[0195] none

Claims

1. An antibacterial nylon 6 material having the structure shown in formula (I): (I) wherein each R1 group and each R2 group are independently selected from C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups and substituted or unsubstituted C7-30 aralkyl groups, or the R1 and R2 groups on the same nitrogen atom together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle; Each R3 group is independently selected from hydrogen (H), C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups; and x and y represent the molar proportion of the repeating unit with structure in formula (I) to the total repeating unit, respectively, wherein when R1 and R2 groups are methyl, x is in the range of 0.12-0.30; y is in the range of 0.70-0.88, and x+y=1; When R1 and R2 groups are independently selected from C2-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups and substituted or unsubstituted C7-30 aralkyl groups, or when R1 and R2 groups on the same nitrogen atom together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle, x is in the range of 0.02-0.30; y is in the range of 0.70-0.98, and x+y=1; wherein the expression "substituted" means that the group is substituted by one or more substituents, and the substituents are C1-18 straight-chain or branched alkyl groups.

2. The antibacterial nylon 6 material as described in claim 1, wherein: Each R1 group and each R2 group is independently selected from C1-12 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl groups and substituted or unsubstituted C7-16 aralkyl groups, or R1 and R2 groups on the same nitrogen atom together with the attached N atom to form a 5-6 member saturated or unsaturated heterocycle; and each R3 group is independently selected from hydrogen (H), C1-12 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl groups and substituted or unsubstituted C7-16 aralkyl groups.

3. The antibacterial nylon 6 material as described in claim 1 or 2, wherein: The total number of repeating units in formula (I) is in the range of 10-2500; and / or the antibacterial nylon 6 material has a weight average molecular weight of 2000-500000.

4. A nylon 6 composition comprising 70 wt% to less than 100 wt% of an antimicrobial nylon 6 material as described in any one of claims 1-3 and 0-30 wt% of at least one polymer different from the antimicrobial nylon 6 material comprising repeating units having a structure and / or repeating units having a structure, wherein groups R1, R2 and R3 are as defined in claim 1.

5. The nylon 6 composition as claimed in claim 4 further comprises 0-30 wt% of additives selected from reinforcing agents, fillers, toughening agents, plasticizers, flame retardants, colorants, fluorescent whitening agents, light stabilizers, antioxidants, heat stabilizers, lubricants, mold release agents, and combinations thereof.

6. A method for preparing an antibacterial nylon 6 material, comprising the following steps: 1) providing a cyclic lysine monomer having the structure shown in formula (II), wherein R1 and R2 groups are independently selected from C1-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups and substituted or unsubstituted C7-30 aralkyl groups, or R1 and R2 groups together with the attached N atom form a 5-7 member saturated or unsaturated heterocycle; 2) When R1 and R2 groups are methyl, the cyclic lysine monomer is ring-opened with caprolactam monomer at a molar ratio of 12:88 to 30:

70. When R1 and R2 groups are independently selected from C2-24 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-12 alicyclic hydrocarbon groups, substituted or unsubstituted C6-18 aryl groups, and substituted or unsubstituted C7-30 aralkyl groups, or when R1 and R2 groups on the same nitrogen atom form a 5-7 member saturated or unsaturated heterocycle together with the attached N atom, the cyclic lysine monomer is ring-opened with caprolactam monomer at a molar ratio of 2:98 to 30:70 to obtain a copolymer having the structure shown in formula (III), (III), 3) The copolymer is reacted with a halide having the structure shown in formula (IV), R3-Hal (IV), Wherein R3 group is selected from hydrogen (H), C1-24 straight-chain or branched aliphatic hydrocarbon group, substituted or unsubstituted C3-12 alicyclic hydrocarbon group, substituted or unsubstituted C6-18 aryl group and substituted or unsubstituted C7-30 aralkyl group, Hal represents halogen, to obtain antibacterial nylon 6 material having the structure shown in formula (I), (I), wherein the expression "substituted" means that the group is substituted by one or more substituents, said substituents being C1-18 straight-chain or branched alkyl groups, wherein the reaction in step 3) is carried out in a solvent selected from trifluoroethanol, benzyl alcohol, cyclohexanol, or combinations thereof.

7. The method as described in request item 6, wherein: R1 and R2 groups are independently selected from C1-12 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl groups, and substituted or unsubstituted C7-16 aralkyl groups, or R1 and R2 groups together with the attached N atom form a 5-6 member saturated or unsaturated heterocycle; and R3 group is selected from hydrogen (H), C1-12 straight-chain or branched aliphatic hydrocarbon groups, substituted or unsubstituted C3-6 alicyclic hydrocarbon groups, substituted or unsubstituted C6-10 aryl groups, and substituted or unsubstituted C7-16 aralkyl groups.

8. The method as described in request item 6, wherein, In step 1), the cyclic lysine monomer, (V), is provided by protecting the primary amine group on the aminocaprolactam of formula (V) with a protecting group.

9. The method of claim 8, wherein step 1) is achieved by reacting the aminocaprolactam with an aldehyde and / or a halogenated hydrocarbon having R1 and / or R2 groups.

10. The method of any one of claims 6-9, wherein step 2) is carried out in the presence of a catalyst selected from carbene reagents, guanidine reagents, amidine reagents, phosphazene reagents, alkali metals, alkali metal oxides, alkali metal hydroxides, alkali metal hydrides, alkali metal alkoxides, alkaline earth metals, alkaline earth metal oxides, alkaline earth metal hydroxides, alkaline earth metal hydrides, alkaline earth metal alkoxides, or combinations thereof.

11. The method of claim 10, wherein the total amount of the cyclic lysine monomer and caprolactam monomer in step 2) is in a molar ratio of (10-50):1 to the catalyst.

12. The method of any one of claims 6-9, wherein the ring-opening polymerization in step 2) is carried out in the presence of an activator having the following structure; wherein R is selected from methyl, ethyl, phenyl, tributylphenyl and trifluoromethylphenyl; and the molar ratio of the total amount of the cyclic lysine monomer and caprolactam monomer in step 2) to the activator is (10-50):

1.

13. The method as described in any one of claims 6-9, having one or more of the following features: The reaction conditions of step 2) include: The polymerization reaction temperature is 140-180℃, and the reaction time is 3-6h; the halide with the structure shown in formula (IV) used in step 3) is selected from hydrochloric acid, iodomethane, bromoethane, bromobutane, bromohexane, bromocyclohexane, benzyl bromide, or a combination thereof; the reaction conditions of step 3) include: a reaction temperature of 40-70℃ and a reaction time of 10-12h; and / or step 3) further includes precipitating the reaction product of the copolymer and the halide in ethyl acetate, centrifuging and drying to obtain the antibacterial nylon 6 material.

14. An article comprising an antimicrobial nylon 6 material as described in any one of claims 1-3, a nylon 6 composition as described in claim 4 or 5, or an antimicrobial nylon 6 material prepared by any one of claims 6-13.

15. The article of manufacture as claimed in claim 14 is selected from textiles, daily necessities, building materials, packaging materials and panels.

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