Polymer, packaging material and method for preparing polymer

Abstract

A polymer comprising repeating units comprising aromatic ring moieties in the backbone, wherein the helical polymer structure is provided by a pi-pi interaction between the aromatic ring moieties; a package comprising a polymer; and methods of making the polymer and packaging. The polymer imparts moisture barrier properties and gas barrier properties to the package.

Description

Technical Field

[0001] This invention relates to polymers, packaging materials, and methods for preparing polymers. Background Technology

[0002] Packaging of manufactured food products is a crucial part of today's food industry because it ensures food safety, maintains food quality, and plays a vital role in the production process, brand communication, and digitalization. In fact, several studies have shown that for most consumers, product packaging is a key aspect driving their purchasing decisions.

[0003] Plastic packaging is used frequently in the economy and in people's daily lives. It offers numerous advantages, such as its 3D shape flexibility, its lightweight nature, and its barrier properties. For example, this weight reduction helps save fuel and reduce CO2 emissions during transportation. Its barrier properties help reduce food waste by positively impacting shelf life. Barrier properties also help ensure food safety.

[0004] Both industry and commerce have made significant efforts to reduce plastic waste. Replacing plastic with paper or fiber-based solutions in food packaging is a future direction, but it is not an easy task. Changes in packaging materials must not compromise consumer safety or product quality, nor generate food waste. Packaging must protect food, but it must also be robust enough to withstand machine handling during production and allow for effective display of the food product.

[0005] There is a need in the field for materials with moisture and oxygen barrier properties. Summary of the Invention

[0006] The object of this invention is to improve upon the prior art, and in particular to provide new polymers that increase the barrier properties against moisture and gas; and to provide packaging materials containing the new polymers and methods for preparing the new polymers.

[0007] Therefore, the object of the invention is achieved by the subject matter of the independent claims. The dependent claims further expand the concept of the invention.

[0008] The inventors propose to solve the above problems by providing a polymer having a main chain containing repeating units with aromatic cyclic moieties, wherein the helical polymer structure is provided by π-π interactions between the aromatic cyclic moieties.

[0009] The present invention further provides packaging materials comprising the polymer according to the present invention.

[0010] The present invention further provides a method for preparing the polymer according to the present invention. Detailed Implementation definition

[0011] As used in this specification, the words “including,” “contains,” and similar terms should not be construed as having an exclusive or exhaustive meaning. In other words, these terms are intended to mean “including but not limited to.” polymer

[0012] The present invention provides a polymer having a main chain comprising repeating units containing aromatic cyclic moieties, wherein the helical polymer structure is provided by π-π interactions between the aromatic cyclic moieties.

[0013] Several factors contribute to the polymer's ability to act as a good barrier against water and gas vapors. These include: Polymers with high crystallinity, low free volume, and high glass transition temperature (Tg) tend to have lower water vapor transmission rate (WVTR) values. • Because nonpolar groups lack attraction for water, polymers with low polarity tend to have lower WVTR values. Water molecules cannot easily pass through the matrix, resulting in higher water vapor barrier properties. Polymers with high molecular weight and low branching levels tend to have lower WVTR values ​​due to their higher chain entanglement and reduced free volume. Crosslinking of polymer chains can reduce free volume and increase polymer density, resulting in a lower WVTR. • Adding barrier additives such as metal oxides, clays, or carbon nanotubes can improve the barrier properties of polymers by reducing free volume and increasing the tortuosity of water vapor diffusion paths. • Because the diffusion path of water vapor is relatively long, the film thickness has a linear effect on diffusion and therefore a linear effect on WVTR.

[0014] The inventors recognized that polymers containing aromatic rings in their main chain, such as isoquinolines linked to hydroxybenzoic acid or hydroxypyridine carboxylic acid via ester functional groups and polymers of divinylpyridine, have the potential to exhibit better water vapor barrier properties compared to conventional polymers. Not wishing to be bound by theory, the inventors propose that this is because aromatic rings can interact through π-π stacking interactions, which can lead to the formation of a helical conformation. This helical conformation can confer a smaller polymer volume and higher stackability, which can reduce the free volume of the polymer and restrict the diffusion of water molecules through the polymer. Therefore, the helical structure provides greater stability than linear stacking structures in polymer materials. The inventors recognized that this is because the helical structure allows for higher stacking efficiency and reduces the free volume of the polymer, which can increase the mechanical and thermal stability of the polymer. Furthermore, the aromatic rings confer hydrophobic properties to the polymer, thereby restricting the diffusion of water molecules through the polymer.

[0015] In a preferred embodiment, the polymer comprises repeating units in the main chain containing an aromatic moiety selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

[0016] In a preferred embodiment, the polymer comprises repeating units in the main chain containing two aromatic moieties, which are independently selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

[0017] In a preferred embodiment, the polymer backbone includes repeating units of formula (I).

[0018]

[0019] (I)

[0020] in

[0021] X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N.

[0022] X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 1 ,

[0023] Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The 0s, 1s, or 2s in N represent N.

[0024] Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The four, five, or six of them are CR 1 ,

[0025] L is selected from the following groups: C(=O)O, OC(=O), NR 1 C(=O) and C(=O)NR 1 ,

[0026] M is selected from the following groups: C(=O)O and OC(=O).

[0027] Each R 1 Choose independently the group consisting of the following items: H and CH3.

[0028] In a preferred embodiment, L is C(=O)O or C(=O)NR. 1 .

[0029] In the preferred embodiment, X 1 X 2 X 3 X 4 Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 One of them is N, and the rest are CR. 1 For example, X 1 X 2 Y 1 Or Y 4 It is N.

[0030] In the preferred embodiment, each R 1 It's H.

[0031] In a preferred embodiment, M is C(=O)O.

[0032] When L is NR 1 (C=O) or C(=O)NR 1 In this configuration, the helical conformation can be stabilized and enhanced through hydrogen bonding between the amide group and the adjacent hydroxyl group, thereby conferring a smaller polymer volume and higher stackability. This reduces the free volume of the polymer and restricts the diffusion of water molecules through the polymer.

[0033] In other embodiments, the polymer backbone includes repeating units of type (II).

[0034]

[0035] (II)

[0036] in

[0037] X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N.

[0038] X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 2 ,

[0039] Y 1 Y 2 Y 3 and Y 4 The 0s, 1s, or 2s in N represent N.

[0040] Y 1 Y 2 Y 3 and Y 4 Two, three, or four of them are CR 2 ,

[0041] L 2 It is an aliphatic hydrocarbon chain with a length of 2n+2.

[0042] n is an integer from 0 to 4.

[0043] Each R 2 Independently select the group consisting of the following items: H, CH3, OR 3 and CH2OR 3 ,and

[0044] R 3 It is H or C1-C6 alkyl.

[0045] In the preferred embodiment, X 1 X 2 X 3 and X 4 One of them and Y 1 Y 2 Y 3 and Y 4 One of them is N, and the rest are CR. 2 For example, polymers can be formed from divinylpyridine monomers (DVP polymers).

[0046] In some implementation schemes, X 1 and Y 1 Same, X 2 and Y 2 Same, X 3 and Y 3 Same, and X 4 and Y 4 Same. In other implementations, X 1 and Y 1 Different, X 2 and Y 2 Same, X 3 and Y 3 Same, and X 4 and Y 4 same.

[0047] In a preferred embodiment, n is 0 or 1. 2 The preferred form is CH2CH2 or CH2CH2CH2CH2. When n is 0, L 2 It is CH2CH2. When n is not 0, that is, L is CH2CH2CH2CH2 or longer, the flexible structure of the polymer allows for more freedom in adopting different helical conformations, thus producing different WVTR properties.

[0048] Polymers formed from divinylpyridine monomers exhibit improved water vapor barrier properties due to their unique structure. Due to the π-stacking possibility of the flexible ethylene backbone and aromatic moieties, DVP polymers can form helical structures, leading to a reduction in free volume and an increase in stacking efficiency. This helical conformation also results in hydrogen bonding between the pyridine nitrogen and carbonyl oxygen of adjacent monomers, further stabilizing the structure. The resulting polymers can have higher glass transition temperatures (Tg) and lower WVTRs compared to polymers stacked linearly. Furthermore, the divinylpyridine monomers impart hydrophobic properties to the polymers, thus restricting the diffusion of water molecules through the polymer.

[0049] In the preferred embodiment, X 1 It is CR 2 And R 2 It is CH3. Otherwise, R 2 H is preferred.

[0050] In the preferred embodiment, R 3 When present, it is H or CH3. In a particularly preferred embodiment, R 3 When present, it is CH3.

[0051] Polymers having a main chain containing repeating units of any one of formulas (1) to (10) are particularly preferred.

[0052] (1)

[0053] (2)

[0054] (3)

[0055] (4)

[0056] (5)

[0057] (6)

[0058] (7)

[0059] (8)

[0060] (9)

[0061] (10).

[0062] The polymers according to the invention can be prepared as homopolymers consisting of repeating units disclosed herein, or as copolymers comprising repeating units disclosed herein and at least one additional repeating unit.

[0063] When the polymer is provided in copolymer form, the polymer may comprise a polymer portion selected from the group consisting of: ethylene-acrylic acid and / or methacrylic acid copolymers, propylene-acrylic acid copolymers, polyesters, polyolefins, polyvinylidene chloride (PVDC), polybutylene succinate, thermoplastic starch, or combinations thereof. The copolymer may be provided in the form of block copolymers, random copolymers, alternating copolymers, or graft copolymers.

[0064] The polymers defined herein can be identified by reference to repeating units in their main chain. The final polymer according to the invention also has terminal groups. Terminal groups can be any suitable terminal groups commonly found in polymers. In some embodiments, each terminal group is independently selected from the group consisting of: R 4 OR 4 、N(R 4 )2 C(=O)OR 4 OC(=O)R 4 C(=O)NHR 4 and NHC(=O)R 4 , where each R 4 Independently select the group consisting of the following items: H, C1-C 12 Alkyl (especially methyl), C2-C 12 Alkenyl (especially vinyl) and C2-C 12 Alkyne group.

[0065] In a preferred embodiment of formula (I), the terminal groups are independently selected from the group consisting of: OR 4 、N(R 4 )2C(=O)OR 4 OC(=O)R 4 C(=O)NHR 4 and NHC(=O)R 4 .

[0066] In a preferred embodiment of formula (II), the terminal group is independently selected from the group consisting of: C2-C6 alkenyl, particularly vinyl. Packaging materials

[0067] This invention provides packaging materials comprising polymers according to the invention. In a preferred embodiment, the packaging material is a film.

[0068] Polymers can be supplied as standalone films. Polymers can also be incorporated into composite packaging materials, such as laminates, foils, and paper-based packaging materials.

[0069] In some implementations, the polymer is a stand-alone membrane. The stand-alone membrane may have a thickness of 5µm to 50µm.

[0070] Composite packaging materials, such as laminates, foils, and paper-based packaging materials, may contain the polymer according to the invention as an extruded layer or a dispersed layer disposed between other layers or as a coating. The polymer layers may have a basis weight in the range of about 1 gsm to about 30 gsm.

[0071] Composite packaging materials may include one or more of the following:

[0072] - An additional polymer layer. For example, the additional polymer layer may comprise a polymer selected from the group consisting of: ethylene-acrylic acid and / or methacrylic acid copolymers, propylene-acrylic acid copolymers, polyesters, polyolefins, polyvinylidene chloride (PVDC), polybutylene succinate, thermoplastic starch, or combinations thereof. The additional polymer layer has a basis weight in the range of about 1 gsm to about 100 gsm.

[0073] - Paper layer. For example, the paper layer may have a basis weight in the range of about 20 gsm to about 360 gsm, depending on the application.

[0074] - Adhesive layer. For example, the adhesive layer may comprise a polymer selected from the group consisting of: latex / casein blends, starch, sugar derivatives, cellulose, amino resins, (poly)acrylates, polyvinyl alcohol (PVOH), ethylene vinyl alcohol (EVOH), polyvinyl acetate, polyacrylic acid, maleic acid-modified ethylene copolymers, methylcellulose, carboxymethylcellulose, carboxyl-functionalized polyesters, polyethylene succinate, polybutylene succinate, ionomers or hydrophilic polyurethanes, or combinations thereof. The adhesive layer may have a basis weight in the range of about 1 gsm to about 50 gsm.

[0075] - A metallization layer. For example, the metallization layer may comprise any of the following: aluminum, aluminum oxide (AIOx), or silicon oxide (SiOx), or a combination thereof. The metallization layer may have a thickness in the range of about 1 nm to about 500 nm.

[0076] - Polymer film. For example, the polymer film may include an oriented film. The polymer film may comprise any of the following selected from the group consisting of oriented polypropylene (OPP), oriented polyester (OPET), oriented polyethylene (OPE), oriented polyamide (OPA), or oriented polylactic acid (OPLA), or combinations thereof. The polymer film may have a basis weight in the range of about 1 gsm to about 100 gsm.

[0077] Unwilling to be bound by theory, the inventors believe that the unique helical polymer structure provided by the π-π stacking between aromatic ring moieties will offer excellent moisture barrier (low WVTR) and gas barrier (low oxygen permeability - OTR) properties. Furthermore, the aromatic properties of these polymers impart hydrophobic characteristics, which in turn provide moisture barrier properties.

[0078] Therefore, when measured at 25°C and 85% relative humidity, the packaging material prepared using the polymer according to the invention is expected to have a density of less than 2 (g•mm) / (m²). 2 •day), more preferably less than 1(g•mm) / (m 2 • days), less than 0.5 (g•mm) / (m 2 • days), less than 0.1 (g•mm) / (m 2 • day) or less than 0.05 (g•mm) / (m 2 •day) of WVTR.

[0079] Crucially, the WVTR of the packaging material having the polymer according to the invention is expected to be 90% or less of the WVTR of the same packaging material except that polyethylene is used instead of the polymer according to the invention. Furthermore, the WVTR of the packaging material according to the invention is preferably 80% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or even 5% or less of the WVTR of the same packaging material except that polyethylene is used instead of the polymer according to the invention.

[0080] When measured at 23°C, 50% relative humidity, and 20.95% oxygen concentration, the packaging material prepared using the polymer according to the invention is expected to have a viscosity of less than 50 (cm²). 3 •mm) / (m 2 • day), preferably below 45 (cm) 3 •mm) / (m 2 • day), below 40 (cm) 3 •mm) / (m 2 • day), below 30 (cm) 3 •mm) / (m 2 • day), below 25 (cm) 3•mm) / (m 2 • day), below 10 (cm) 3 •mm) / (m 2 • day), less than 1 (cm) 3 •mm) / (m 2 • day) or below 0.2 (cm) 3 •mm) / (m 2 • Oxygen barrier transfer rate (OTR) per day.

[0081] Crucially, the OTR of the packaging material having the polymer according to the invention is expected to be 90% or less of the OTR of the same packaging material except that polyethylene is used instead of the polymer according to the invention. Furthermore, the OTR of the packaging material according to the invention is preferably 80% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or even 5% or less of the OTR of the same packaging material except that polyethylene is used instead of the polymer according to the invention. synthesis

[0082] A method for forming a polymer according to the invention comprises contacting a first reagent containing an aromatic cyclic moiety with a second reagent containing an aromatic moiety under conditions sufficient to form a polymer according to the invention.

[0083] In a preferred embodiment, the first reagent and the second reagent each comprise an aromatic moiety selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

[0084] For example, the first reagent can be a compound of formula (A).

[0085] (A)

[0086] in

[0087] X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N.

[0088] X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 1 ,

[0089] Q is OH or NH2, and

[0090] Each R 1Choose independently the group consisting of the following items: H and CH3.

[0091] The second reagent can be a compound of formula (B).

[0092] (B)

[0093] in

[0094] Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The 0s, 1s, or 2s in N represent N.

[0095] Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The four, five, or six of them are CR 1 ,

[0096] T is OH or NH2, and

[0097] Each R 1 Choose independently the group consisting of the following items: H and CH3.

[0098] In the preferred embodiment, X 1 X 2 X 3 X 4 Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 One of them is N, and the rest are CR. 1 For example, X 1 X 2 Y 1 Or Y 4 One of them is N.

[0099] In the preferred embodiment, R 1 It's H.

[0100] In an alternative embodiment, the first reagent and the second reagent are each compounds of formula (C).

[0101] (C)

[0102] in

[0103] X 1X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N.

[0104] X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 2 ,

[0105] n is an integer from 0 to 4.

[0106] Each R 2 Independently select the group consisting of the following items: H, CH3, OR 3 and CH2OR 3 ,and

[0107] R 3 It is H or C1-C6 alkyl.

[0108] In the preferred embodiment, X 1 X 2 X 3 and X 4 One of them is N, and the rest are CR. 2 For example, X 2 or X 4 One of them is N.

[0109] In the preferred embodiment, X 1 It is CR 2 And R 2 It is CH3.

[0110] In a preferred embodiment, n is 0 or 1.

[0111] In the preferred embodiment, R 2 It is H. In the preferred embodiment, R 3 It is H or CH3, with CH3 being preferred.

[0112] The invention will now be illustrated by reference to the following non-limiting embodiments. Other arrangements are also contemplated within the scope of the appended claims. Example 1: Isoquinoline esters of hydroxybenzoic acid or hydroxypyridinecarboxylic acid

[0113] Isoquinoline esters of hydroxybenzoic acid or hydroxypyridinecarboxylic acid can be synthesized using conventional esterification reactions, such as Fischer esterification using acid catalysts or Steglich esterification using carbodiimide chemistry. Protecting the hydroxy functional group of hydroxybenzoic acid and the carboxylic acid of the isoquinoline moiety with a benzyl group allows for selective coupling of the two moieties. Subsequent deprotection provides a monomer, which can then be reacted with itself using Fischer esterification to form a polyester.

[0114] Example 2: Isoquinoline esters of 2-hydroxybenzoic acid or hydroxypyridinecarboxylic acid

[0115] Isoquinoline amides of hydroxybenzoic acid or hydroxypyridinecarboxylic acid can be synthesized using coupling reagents based on carbodiimide chemistry. The hydroxyl functional groups of the carboxylic acid and hydroxybenzoic acid of the isoquinoline amide need to be protected to allow for selective amide bond formation. Subsequent deprotection provides the monomer, which can then be reacted with itself using Fischer esterification to form a polyester.

[0116] Example 3 - Polymer of divinylpyridine

[0117] Divinylpyridine monomers can also be synthesized via olefin metathesis using ruthenium catalysts (such as Grubbs catalysts). This method will provide the following structures:

[0118] Example 4 - Moisture and Oxygen Barrier Properties

[0119] Computational analysis was performed on polymers containing repeating units according to the present invention to evaluate their moisture barrier properties (WVTR) and oxygen barrier properties (OTR). The following values ​​were obtained.

[0120] The WVTR was evaluated at 23°C and 85% relative humidity. The OTR was evaluated at 23°C, 50% relative humidity, and 20.95% oxygen concentration.

[0121]

[0122] Implementation Plan

[0123] Various preferred features and embodiments of the invention will now be described with reference to the following numbered paragraphs.

[0124] 1. A polymer comprising repeating units in the main chain including an aromatic cyclic moiety.

[0125] The helical polymer structure is provided by the π-π interactions between aromatic ring moieties.

[0126] 2. The polymer according to paragraph 1, wherein the aromatic portion is selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

[0127] 3. The polymer according to paragraph 1 or paragraph 2, wherein the repeating unit comprises two aromatic moieties in the main chain, the two aromatic moieties being independently selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

[0128] 4. A polymer comprising a repeating unit of formula (I).

[0129]

[0130] (I)

[0131] in

[0132] X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N.

[0133] X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 1 ,

[0134] Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The 0s, 1s, or 2s in N represent N.

[0135] Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The four, five, or six of them are CR 1 ,

[0136] L is selected from the following groups: C(=O)O, OC(=O), NR 1 C(=O) and C(=O)NR 1 ,

[0137] M is selected from the following groups: C(=O)O and OC(=O), and

[0138] Each R 1 Choose independently the group consisting of the following items: H and CH3.

[0139] 5. The polymer according to paragraph 4, wherein L is C(=O)O or C(=O)NR. 1 .

[0140] 6. The polymer according to paragraph 4 or paragraph 5, wherein X 1 X 2 X 3 X 4 Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 One of them is N, and the rest are CR. 1 .

[0141] 7. The polymer according to any one of paragraphs 4 to 6, wherein X 1 X 2 Y 1 Or Y 4 One of them is N.

[0142] 8. The polymer according to any one of paragraphs 4 to 7, wherein R 1 It's H.

[0143] 9. The polymer according to any one of paragraphs 4 to 8, wherein M is C(=O)O.

[0144] 10. A polymer comprising a repeating unit of formula (II).

[0145]

[0146] (II)

[0147] in

[0148] X 1 X 2 X 3 and X 4 In the context, 0, 1, or 2 represent N, X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 2 ,

[0149] Y 1Y 2 Y 3 and Y 4 The 0s, 1s, or 2s in N represent N.

[0150] Y 1 Y 2 Y 3 and Y 4 Two, three, or four of them are CR 2 ,

[0151] L 2 It is an aliphatic hydrocarbon chain with a length of 2n+2.

[0152] n is an integer from 0 to 4.

[0153] Each R 2 Independently select the group consisting of the following items: H, CH3, OR 3 and CH2OR 3 ,and

[0154] R 3 It is H or C1-C6 alkyl.

[0155] 11. The polymer according to paragraph 10, wherein X 1 X 2 X 3 and X 4 One of them and Y 1 Y 2 Y 3 and Y 4 One of them is N, and the rest are CR. 2 .

[0156] 12. The polymer according to paragraph 10 or 11, wherein X 2 and X 4 One of them is N, and Y 2 and Y 4 One of them is N.

[0157] 13. The polymer according to any one of paragraphs 10 to 12, wherein X 1 and Y 1 and Y 2 One of them is CR 2 And R 2 It is CH3.

[0158] 14. The polymer according to any one of paragraphs 10 to 13, wherein R 2 It's H.

[0159] 15. A polymer comprising repeating units of any one of formulas (1) to (10).

[0160] (1)

[0161] (2)

[0162] (3)

[0163] (4)

[0164] (5)

[0165] (6)

[0166] (7)

[0167] (8)

[0168] (9)

[0169] (10).

[0170] 16. Packaging material comprising a polymer according to any one of paragraphs 1 to 15, preferably wherein the packaging material is a film.

[0171] 17. The packaging material according to paragraph 16, wherein the moisture barrier transfer rate (WVTR) is less than 2 (g•mm) / (m²) when measured at 25°C and 85% relative humidity. 2 •sky).

[0172] 18. The packaging material according to paragraph 16 or 17, wherein the moisture barrier transfer rate (WVTR) is 90% or less of the moisture barrier transfer rate (WVTR) of an equivalent packaging material comprising polyethylene rather than the polymer according to any one of claims 1 to 15.

[0173] 19. The packaging material according to any one of paragraphs 16 to 18, wherein the oxygen barrier transfer rate (OTR) is less than 50 (cm²) when measured at 23°C, 50% relative humidity, and 20.95% oxygen concentration. 3 •mm) / (m 2 •sky).

[0174] 20. The packaging material according to any one of paragraphs 16 to 19, wherein the oxygen barrier transfer rate (OTR) is 90% or less of the oxygen barrier transfer rate (OTR) of an equivalent packaging material comprising polyethylene rather than the polymer according to any one of claims 1 to 15.

[0175] 21. A method for forming a polymer, wherein the method comprises contacting a first reagent comprising an aromatic cyclic moiety with a second reagent comprising an aromatic moiety under conditions sufficient to form a polymer according to any one of paragraphs 1 to 15.

[0176] 22. The method according to paragraph 21, wherein the first reagent and the second reagent each comprise an aromatic moiety selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

[0177] 23. The method according to paragraph 21 or paragraph 22, wherein the first reagent is a compound of formula (A).

[0178] (A)

[0179] in

[0180] X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N.

[0181] X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 1 ,

[0182] Q is OH or NH2, and

[0183] Each R 1 Choose independently the group consisting of the following items: H and CH3.

[0184] 24. The polymer according to paragraph 23, wherein R 1 It's H.

[0185] 25. The method according to any one of paragraphs 21 to 24, wherein the second reagent is a compound of formula (B).

[0186] (B)

[0187] in

[0188] Y 1 Y2 Y 3 Y 4 Y 5 and Y 6 The 0s, 1s, or 2s in N represent N.

[0189] Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The four, five, or six of them are CR 1 ,

[0190] T is OH or NH2, and

[0191] Each R 1 Choose independently the group consisting of the following items: H and CH3.

[0192] 26. According to the polymer described in paragraph 25, wherein X 1 X 2 X 3 X 4 Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 One of them is N, and the rest are CR. 1 .

[0193] 27. The polymer according to paragraph 25 or 26, wherein X 1 X 2 Y 1 Or Y 4 One of them is N.

[0194] 28. The method according to paragraph 21 or paragraph 22, wherein the first reagent and the second reagent are each compounds of formula (C).

[0195] (C)

[0196] in

[0197] X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N.

[0198] X 1 X 2 X 3 and X 4 Two, three, or four of them are CR2 ,

[0199] n is an integer from 1 to 4.

[0200] Each R 2 Independently select the group consisting of the following items: H, CH3, OR 3 and CH2OR 3 ,and

[0201] R 3 It is H or C1-C6 alkyl.

[0202] 29. According to the method described in paragraph 28, where X 1 X 2 X 3 and X 4 One of them is N, and the rest are CR. 2 .

[0203] 30. The polymer according to paragraph 28 or 29, wherein X 2 or X 4 One of them is N.

[0204] 31. The polymer according to any one of paragraphs 28 to 30, wherein X 1 It is CR 2 And R 2 It is CH3.

[0205] 32. The polymer according to any one of paragraphs 28 to 31, wherein R 2 It's H.

Claims

1. A polymer comprising repeating units in the main chain including an aromatic cyclic moiety. The helical polymer structure is provided by the π-π interactions between aromatic ring moieties.

2. The polymer according to claim 1, wherein the aromatic portion is selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

3. The polymer according to claim 1 or claim 2, wherein the repeating unit contains two aromatic moieties in the main chain, the two aromatic moieties being independently selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

4. The polymer according to any one of claims 1 to 3, wherein the polymer comprises a repeating unit of formula (I). (I) in X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N. X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 1 , Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The 0s, 1s, or 2s in N represent N. Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The four, five, or six of them are CR 1 , L is selected from the following groups: C(=O)O, OC(=O), NR 1 C(=O) and C(=O)NR 1 , M is selected from the following groups: C(=O)O and OC(=O). Each R 1 Choose independently the group consisting of the following items: H and CH3.

5. The polymer according to any one of claims 1 to 3, wherein the polymer comprises a repeating unit of formula (II). (II) X 1 X 2 X 3 and X 4 The 0s, 1s, or 2s in N represent N. X 1 X 2 X 3 and X 4 Two, three, or four of them are CR 2 , Y 1 Y 2 Y 3 and Y 4 The 0s, 1s, or 2s in N represent N. Y 1 Y 2 Y 3 and Y 4 Two, three, or four of them are CR 2 , L 2 It is an aliphatic hydrocarbon chain with a length of 2n+2. n is an integer from 0 to 4. Each R 2 Independently select the group consisting of the following items: H, CH3, OR 3 and CH2OR 3 ,and R 3 It is H or C1-C6 alkyl.

6. The polymer according to any one of claims 1 to 5, wherein the polymer comprises repeating units of any one of formulas (1) to (10). (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)。 7. Packaging material comprising the polymer according to any one of claims 1 to 6.

8. The packaging material according to claim 7, wherein the moisture barrier transfer rate (WVTR) is less than 2 (g•mm) / (m²) when measured at 23°C and 85% relative humidity. 2 •sky).

9. The packaging material according to claim 7 or claim 8, wherein the moisture barrier transfer rate (WVTR) is 90% or less of the moisture barrier transfer rate (WVTR) of an equivalent packaging material comprising polyethylene rather than the polymer according to any one of claims 1 to 8.

10. The packaging material according to any one of claims 7 to 9, wherein the oxygen barrier transfer rate (OTR) is less than 50 (cm²) when measured at 23°C, 50% relative humidity, and 20.95% oxygen concentration. 3 •mm) / (m 2 •sky).

11. The packaging material according to any one of claims 7 to 10, wherein the oxygen barrier transfer rate (OTR) is 90% or less of the oxygen barrier transfer rate (OTR) of an equivalent packaging material comprising polyethylene rather than the polymer according to any one of claims 1 to 8.

12. A method for forming a polymer, wherein the method comprises contacting a first reagent comprising an aromatic cyclic moiety with a second reagent comprising an aromatic moiety under conditions sufficient to form a polymer according to any one of claims 1 to 8.

13. The method of claim 12, wherein the first reagent and the second reagent each comprise an aromatic moiety selected from the group consisting of: benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cyclophosphine, and phthalazine.

14. The method according to claim 12 or claim 13, wherein the first reagent is a compound of formula (III). (A) in X 1 X 2 X 3 and X 4 One or two of them are N. X 1 X 2 X 3 and X 4 Two or three of them are CR 1 , Q is OH or NH2, and Each R 1 Independently select the group consisting of the following items: H and CH3; and The second reagent is a compound of formula (B). (B) in Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The 0s, 1s, or 2s in N represent N. Y 1 Y 2 Y 3 Y 4 Y 5 and Y 6 The four, five, or six of them are CR 1 , T is OH or NH2, and Each R 1 Choose independently the group consisting of the following items: H and CH3.

15. The method according to claim 12 or claim 13, wherein the first reagent and the second reagent are each compounds of formula (C). (C) X 1 X 2 X 3 and X 4 One or two of them are N. X 1 X 2 X 3 and X 4 Two or three of them are CR 2 , n is an integer from 0 to 4. Each R 2 Independently select the group consisting of the following items: H, CH3, OR 3 and CH2OR 3 ,and R 3 It is H or C1-C6 alkyl.

Images