Blend for wet-end oil / grease-resistant molded fibers and use thereof

Abstract

The present invention relates to the field of molded fiber food packaging, in particular to a blend for wet-end molded fibers and the use thereof. The blend comprises the following components: a polymer containing a repeating unit derived from styrene and a repeating unit derived from an unsaturated carboxylic acid and / or containing a repeating unit derived from styrene and a repeating unit derived from an unsaturated acid anhydride; a polysaccharide (preferably starch); and wax. The blend of the present invention does not contain any PFAS components, thus meeting environmental protection requirements while avoiding possible health risks caused by PFAS. Moreover, the blend can be applied to a wet end, which is a non-surface treatment process, thereby better meeting the requirement of molded fiber food packaging for oil / grease resistance.

Description

Blends for oil resistant wet end molded fiber and use thereof TECHNICAL FIELD

[0001] The present invention relates to the field of molded fiber food packaging, in particular to blends for oil resistant (OGR) wet end molded fiber and use thereof. BACKGROUND

[0002] Per-and polyfluoroalkyl substances (PFAS) are widely used in the field of food packaging due to their excellent water and oil resistant properties, for example, as surface coatings of paper and paperboard that come into contact with food. However, PFAS are not easily biodegradable, and they can accumulate in the environment and in the human body, posing a risk to human health.

[0003] Molded fiber food packaging has been rapidly developed in recent years due to its environmentally friendly properties of being easily biodegradable and being easy to be molded into various desired shapes (e.g., trays, bowls, etc. of various specifications and shapes). However, due to the limitations of its production process, surface treatment processes such as surface sizing or coating cannot be used to treat molded fiber food packaging for oil and / or water resistance.

[0004] Therefore, there is an urgent need in the field of molded fiber food packaging for a non-surface treatment process that can improve the oil and / or water resistance of molded fiber food packaging while being environmentally friendly and safe. SUMMARY

[0005] The present invention provides a blend comprising:

[0006] a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid and / or repeating units derived from an unsaturated anhydride;

[0007] a polysaccharide; and

[0008] a wax.

[0009] The present invention provides a blend comprising:

[0010] a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid and / or repeating units derived from an unsaturated anhydride;

[0011] a polysaccharide; and

[0012] a wax.

[0013] In one embodiment, the blend can be used for wet end molded fiber. The blend can impart good oil resistant properties to the resulting molded fiber product.

[0014] In an embodiment, the blend can be used to provide a fiber aid, in particular to provide a (wet-end) molding fiber aid.

[0015] In an embodiment, the polysaccharide comprises at least two monosaccharide units, for example, at least 2, at least 3, at least 4, at least 5, at least 10, at least 100, at least 1000, at least 5000, at least 10,000 monosaccharide units.

[0016] The number of repeating units can also be referred to as the degree of polymerization. In an embodiment, the polysaccharide described herein has a degree of polymerization of 2-10,000, for example, 2, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10,000, or a sub-range consisting of any of these ranges.

[0017] In an embodiment, the monosaccharide in the polysaccharide can be a five- or six-carbon sugar. For example, a five-carbon sugar such as Ribose, Arabinose, Xylose, Lyxose, Ribulose, Xylulose, and a six-carbon sugar such as Glucose, Mannose, Galactose, Fructose, Sorbose.

[0018] In an embodiment, the polysaccharide contains only one type of monosaccharide, examples of such polysaccharides include, for example, starch, Cellulose, Glucan, Fructo oligosaccharide, Polyfructose.

[0019] In an embodiment, the polysaccharide contains two or more types of monosaccharides, examples of such polysaccharides include, for example, Hemicellulose, Agarose.

[0020] In an embodiment, the monosaccharide in the polysaccharide can be modified, examples of such polysaccharides include, for example, Chitosan, Pectin.

[0021] In one embodiment, the polysaccharide is cationically modified. For example, the cationic degree of substitution can be 0.01-0.5, e.g., 0.01, 0.02, 0.03, 0.04, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, or 0.5, or a sub-range consisting of any of these values.

[0022] In one embodiment, the polymer contains repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid.

[0023] In one embodiment, the polymer contains repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid.

[0024] In one embodiment, the repeating units derived from styrene have the following structural formula:

[0025] wherein, at each occurrence, any of R 1 , R 2 , and R 3 is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 alkynyl, or substituted C2-C6 alkynyl, the substituents being selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 alkynyl,

[0026] * denotes a point of attachment.

[0027] In one embodiment, the repeating units derived from an unsaturated carboxylic acid have the following structural formula:

[0028] wherein, at each occurrence, any of R 4 and R 5 is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 alkynyl, or substituted C2-C6 alkynyl, the substituents being selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 alkynyl,

[0029] * denotes a point of attachment.

[0030] In one embodiment, the repeating units derived from an unsaturated carboxylic acid have the following structural formula:

[0031] wherein R 6 and R 7 are each, at each occurrence, independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 alkynyl, or substituted C2-C6 alkynyl, the substituents being selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 alkynyl,

[0032] M and M' are each, at each occurrence, independently selected from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ), or H + ,

[0033] * indicates a point of attachment.

[0034] In one embodiment, the repeating unit derived from an unsaturated carboxylic acid has the following structural formula:

[0035] wherein R 8 , R 9 and R 10 are each, at each occurrence, independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 alkynyl, or substituted C2-C6 alkynyl, the substituents being selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 alkynyl,

[0036] M" is independently selected, at each occurrence, from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ), or H + ,

[0037] * indicates a point of attachment.

[0038] In one preferred embodiment, the repeating unit derived from an unsaturated carboxylic acid has the following structural formula:

[0039] wherein R 11independently at each occurrence selected from H, unsubstituted C1-C6alkyl, substituted C1-C6alkyl, unsubstituted C2-C6alkenyl, substituted C2-C6alkenyl, unsubstituted C2-C6alkynyl, or substituted C2-C6alkynyl, the substituents being selected from the group consisting of carboxyl, hydroxyl, C3-C6cycloalkyl, C1-C6alkoxy, amino, mono- or di-C1-C6alkylamino, nitro, thiol, C2-C6alkenyl or C2-C6alkynyl,

[0040] M”’ is independently at each occurrence selected from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ) or H + ,

[0041] * denotes the point of attachment.

[0042] In one embodiment, the polymer has a structural formula comprising the following repeating unit:

[0043] wherein any of R 1 , R 2 , R 3 , R 4 and R 5 is, independently at each occurrence, selected from H, unsubstituted C1-C6alkyl, substituted C1-C6alkyl, unsubstituted C2-C6alkenyl, substituted C2-C6alkenyl, unsubstituted C2-C6alkynyl, or substituted C2-C6alkynyl, the substituents being selected from the group consisting of carboxyl, hydroxyl, C3-C6cycloalkyl, C1-C6alkoxy, amino, mono- or di-C1-C6alkylamino, nitro, thiol, C2-C6alkenyl or C2-C6alkynyl,

[0044] the molar ratio of a and b is 1 : 1 to 6: 1, preferably 2: 1 to 3: 1,

[0045] — denotes a direct or indirect attachment.

[0046] In one embodiment, the polymer has a structural formula comprising the following repeating unit:

[0047] wherein any of R 1 , R 2 , R 3 , R 6 and R 7Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl.

[0048] Either M or M' is independently selected from alkali metal ions (e.g., Na+) each time it appears. + K + ), ammonium ions (NH4) + ) or H + ,

[0049] The molar ratio of a to c is 1:1 to 6:1, preferably 2:1 to 3:1.

[0050] ---- indicates a direct or indirect connection.

[0051] In one embodiment, the polymer has a structural formula comprising the following repeating units:

[0052] Among them, R 1 R 2 R 3 R 8 R 9 and R 10 Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl.

[0053] "M" is independently selected from alkali metal ions (e.g., Na) each time it appears. + K + ), ammonium ions (NH4) + ) or H + ,

[0054] The molar ratio of a to d is 1:1 to 6:1, preferably 2:1 to 3:1.

[0055] ---- indicates a direct or indirect connection.

[0056] In an embodiment, the polymer has a structural formula comprising the following repeating units:

[0057] wherein R 1 , R 2 , R 3 , and R 11 are each independently selected at each occurrence from H, unsubstituted C1-C6alkyl, substituted C1-C6alkyl, unsubstituted C2-C6alkenyl, substituted C2-C6alkenyl, unsubstituted C2-C6alkynyl, or substituted C2-C6alkynyl, the substituents being selected from carboxyl, hydroxyl, C3-C6cycloalkyl, C1-C6alkoxy, amino, mono- or di-C1-C6alkylamino, nitro, thiol, C2-C6alkenyl, or C2-C6alkynyl,

[0058] M”’ is independently selected at each occurrence from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ), or H + ,

[0059] a and d are in a molar ratio of 1 : 1 to 6: 1, preferably 2: 1 to 3: 1,

[0060] — represents a direct or indirect linkage.

[0061] In an embodiment, the polymer is starch modified.

[0062] In an embodiment, the blend further comprises a hydrophilic modifier that increases the water solubility of the polymer. For example, by reacting with some or all of the repeating units derived from an unsaturated carboxylic acid and / or repeating units derived from an unsaturated anhydride in the polymer to introduce hydrophilic groups.

[0063] In an embodiment, the hydrophilic modifier comprises ammonium hydroxide, sodium hydroxide, and / or potassium hydroxide. Preferably, the hydrophilic modifier comprises ammonium hydroxide. More preferably, the ammonium hydroxide is a 10-30 wt.% (e.g., 10, 15, 20, 25, or 30 wt.%, or a sub-range consisting of any of these ranges) aqueous ammonium hydroxide solution. Most preferably, the hydrophilic modifier comprises a 25 wt.% aqueous ammonium hydroxide solution.

[0064] In an embodiment, the blend further comprises a solvent, for example, water, for example, distilled water, for example, double distilled water.

[0065] In an embodiment, the blend does not comprise, preferably does not comprise, any fluorine-containing substance, e.g., does not comprise perfluoro and polyfluoro alkyl substances.

[0066] In an embodiment, the polymer comprises a styrene maleic anhydride copolymer (SMA).

[0067] In an embodiment, the polymer has a weight average molecular weight of 1000-100000 Da, e.g., 1000, 2000, 3000, 4000, 5000, 10000, 15000, 20000, 25000, 30000, 35000, 40000, 45000, 50000, 55000, 60000, 65000, 70000, 75000, 80000, 85000, 90000, 95000, or 100000 Da, or a sub-range consisting of any of these ranges. Preferably, the polymer has a weight average molecular weight of 5000-30000 Da.

[0068] In an embodiment, the styrene maleic anhydride copolymer has a weight average molecular weight of 1000-100000 Da, e.g., 1000, 2000, 3000, 4000, 5000, 10000, 15000, 20000, 25000, 30000, 35000, 40000, 45000, 50000, 55000, 60000, 65000, 70000, 75000, 80000, 85000, 90000, 95000, or 100000 Da, or a sub-range consisting of any of these ranges. Preferably, the styrene maleic anhydride copolymer has a weight average molecular weight of 5000-30000 Da.

[0069] In an embodiment, the molar ratio of repeating units derived from styrene to repeating units derived from unsaturated anhydride in the polymer is 1:1 to 6:1, e.g., 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, or 6:1, or a sub-range consisting of any of these ranges. Preferably, the molar ratio is 2:1 to 3:1.

[0070] In an embodiment, the molar ratio of repeat units derived from styrene to repeat units derived from unsaturated carboxylic acid in the polymer is 1 : 1 to 6: 1, for example, 1 : 1, 1.5: 1, 2: 1, 2.5: 1, 3: 1, 3.5: 1, 4: 1, 4.5: 1, 5: 1, 5.5: 1, or 6: 1, or a sub-range consisting of any of these ranges. Preferably, the molar ratio is 2: 1 to 3: 1.

[0071] In an embodiment, the molar ratio of repeat units derived from styrene to repeat units derived from unsaturated carboxylic acid in the polymer is 1 : 1 to 6: 1, for example, 1 : 1, 1.5: 1, 2: 1, 2.5: 1, 3: 1, 3.5: 1, 4: 1, 4.5: 1, 5: 1, 5.5: 1, or 6: 1, or a sub-range consisting of any of these ranges. Preferably, the molar ratio is 2: 1 to 3: 1.

[0072] In an embodiment, the molar ratio of repeat units derived from styrene to repeat units derived from unsaturated carboxylic acid in the polymer is 1 : 1 to 6: 1, for example, 1 : 1, 1.5: 1, 2: 1, 2.5: 1, 3: 1, 3.5: 1, 4: 1, 4.5: 1, 5: 1, 5.5: 1, or 6: 1, or a sub-range consisting of any of these ranges. Preferably, the molar ratio is 2: 1 to 3: 1.

[0073] In an embodiment, the starch comprises modified starch. Preferably, the modified starch comprises cationic starch.

[0074] In an embodiment, the cationic starch has a degree of substitution of 0.01 to 0.5, for example, 0.01, 0.02, 0.03, 0.04, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, or 0.5, or a sub-range consisting of any of these ranges.

[0075] In an embodiment, the starch comprises amylose and / or amylopectin. Preferably, the starch comprises amylopectin, for example, waxy corn starch.

[0076] In a preferred embodiment, the starch comprises cationic amylopectin, for example, cationic waxy corn starch.

[0077] In a preferred embodiment, the starch is subjected to gelatinization.

[0078] Waxes, such as paraffin wax, are known and described in, for example, US 2,692,835, WO 2002 / 102941, EP 1498469 and WO 2004 / 009739. Paraffin wax mainly comprises n-alkanes. The paraffin wax according to the present application comprises more than 85 wt.% n-alkanes, preferably more than 90 wt.% n-alkanes.

[0079] In an embodiment, the wax has a freezing point (melting point) of less than or equal to 120°C, such as, for example, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115 or 120°C, or a sub-range consisting of any of these ranges. Preferably, the wax has a freezing point of more than or equal to 50°C and less than or equal to 100°C. Most preferably, the wax has a freezing point of more than or equal to 70°C and less than or equal to 85°C.

[0080] The color intensity of a liquid substance of moderate color is usually quantified using the Saybolt color scale. For this purpose the wax is melted for the measurement. Further, the wax according to the present application has a Saybolt color according to ASTM D156 of at least 25 cm. Preferably, the wax according to the present application has a Saybolt color according to ASTM D156 of at least 30 cm.

[0081] In an embodiment, the wax comprises a natural wax and / or a synthetic wax.

[0082] In an embodiment, the natural wax comprises a plant wax and / or an animal wax. Examples of natural waxes include, for example, candelilla wax, bayberry wax, carnauba wax, castor wax, esparto wax, ouricury wax, rice wax, soy wax, montan wax, ozokerite, petroleum wax, white wax, ear wax, lanolin, shellac wax, whale wax.

[0083] In an embodiment, the synthetic wax comprises a polyethylene wax, a polypropylene wax, a polyamide wax, a Fischer-Tropsch wax, an oxidized polyethylene wax.

[0084] In an embodiment, the wax comprises a polyethylene wax, a Fischer-Tropsch wax and / or a biomass-based wax. Preferably, the wax comprises a Fischer-Tropsch wax.

[0085] In an embodiment, the wax is in a molten state.

[0086] In an embodiment, the blend comprises an aqueous phase comprising the polymer, the polysaccharide (preferably starch) and water.

[0087] In an embodiment, the blend comprises an oil phase comprising the wax in a molten state.

[0088] In an embodiment, the blend comprises 5-15 parts by weight of the polymer, for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 parts, or a sub-range consisting of any values in these ranges.

[0089] In an embodiment, the blend comprises 8-18 parts by weight of the polysaccharide (preferably starch), for example, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 parts, or a sub-range consisting of any values in these ranges.

[0090] In an embodiment, the blend comprises 1-10 parts by weight of the hydrophilic modifier, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 parts, or a sub-range consisting of any values in these ranges. In an embodiment, the amount of hydrophilic modifier is calculated based on 25 wt.% aqueous ammonium hydroxide solution.

[0091] When the hydrophilic modifier is not 25 wt.% aqueous ammonium hydroxide solution, it can be first converted to a solution having the same equivalent (hydrogen ion or hydroxide) as 25 wt.% aqueous ammonium hydroxide solution, and then the amount of hydrophilic modifier is calculated.

[0092] In an embodiment, the blend comprises 200-400 parts by weight of the wax, for example, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, or 400 parts, or a sub-range consisting of any values in these ranges.

[0093] In an embodiment, the blend comprises 500-750 parts by weight of the solvent, for example, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730, 740, or 750 parts, or a sub-range consisting of any values in these ranges.

[0094] In a preferred embodiment, the blend comprises the following ingredients:

[0095] 5-15 parts by weight of a polymer, the polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid, and / or containing repeating units derived from styrene and repeating units derived from an unsaturated anhydride;

[0096] 8-18 parts by weight of a polysaccharide (preferably starch); and

[0097] 200 to 400 parts by weight of a wax.

[0098] In a preferred embodiment, the blend comprises the following ingredients:

[0099] 5 to 15 parts by weight of a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid, and / or containing repeating units derived from styrene and repeating units derived from an unsaturated anhydride;

[0100] 8 to 18 parts by weight of a polysaccharide (preferably starch);

[0101] 200 to 400 parts by weight of a wax; and

[0102] 1 to 10 parts by weight of a hydrophilic modifier.

[0103] In a preferred embodiment, the blend comprises the following ingredients:

[0104] 5 to 15 parts by weight of a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid, and / or containing repeating units derived from styrene and repeating units derived from an unsaturated anhydride;

[0105] 8 to 18 parts by weight of a polysaccharide (preferably starch);

[0106] 200 to 400 parts by weight of a wax;

[0107] 1 to 10 parts by weight of a hydrophilic modifier; and

[0108] 500 to 750 parts by weight of a solvent.

[0109] In a preferred embodiment, the blend comprises the following ingredients:

[0110] a styrene-maleic anhydride copolymer;

[0111] cationically branched starch;

[0112] a Fischer-Tropsch wax.

[0113] In a preferred embodiment, the blend comprises the following ingredients:

[0114] a styrene-maleic anhydride copolymer;

[0115] cationically branched starch;

[0116] a Fischer-Tropsch wax;

[0117] 25 wt. % aqueous ammonium hydroxide solution.

[0118] In a preferred embodiment, the blend further comprises water. In a preferred embodiment, the blend comprises 5-15 parts by weight of the styrene-maleic anhydride copolymer, for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 parts, or a sub-range consisting of any values within these ranges.

[0119] In a preferred embodiment, the blend comprises 8-18 parts by weight of the cationic amylopectin, for example, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 parts, or a sub-range consisting of any values within these ranges.

[0120] In a preferred embodiment, the blend comprises 200-400 parts by weight of the Fischer-Tropsch wax, for example, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, or 400 parts, or a sub-range consisting of any values within these ranges.

[0121] In a preferred embodiment, the blend comprises 1-10 parts by weight of the 25 wt.% aqueous ammonium hydroxide solution, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 parts, or a sub-range consisting of any values within these ranges.

[0122] In a preferred embodiment, the blend comprises 500-750 parts by weight of water, for example, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730, 740, or 750 parts, or a sub-range consisting of any values within these ranges.

[0123] In a preferred embodiment, the blend comprises the following ingredients:

[0124] 5-15 parts by weight of a styrene-maleic anhydride copolymer;

[0125] 8-18 parts by weight of a cationic amylopectin;

[0126] 200-400 parts by weight of a Fischer-Tropsch wax;

[0127] 1-10 parts by weight of a 25 wt.% aqueous ammonium hydroxide solution.

[0128] In a preferred embodiment, the blend comprises the following ingredients:

[0129] styrene-maleic anhydride copolymer;

[0130] cationic amylopectin;

[0131] fischer-tropsch wax;

[0132] 25 wt. % aqueous ammonium hydroxide solution; and

[0133] water.

[0134] In a preferred embodiment, the blend comprises the following ingredients:

[0135] 5-15 parts by weight of styrene-maleic anhydride copolymer;

[0136] 8-18 parts by weight of cationic amylopectin;

[0137] 200-400 parts by weight of fischer-tropsch wax;

[0138] 1-10 parts by weight of 25 wt. % aqueous ammonium hydroxide solution; and

[0139] 500-750 parts by weight of water.

[0140] In an embodiment, the blend comprises 2.0-3.5 wt. % of the polymer, for example, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, or 3.5 wt. %, or a sub-range consisting of any of these ranges.

[0141] In an embodiment, the blend comprises 2.5-4 wt. % of the polysaccharide (preferably starch), for example, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, or 4.0 wt. %, or a sub-range consisting of any of these ranges.

[0142] In an embodiment, the blend comprises 90-95 wt. % of the wax, for example, 90, 90.5, 91, 91.5, 92, 92.5, 93, 93.5, 94, 94.5, or 95 wt. %, or a sub-range consisting of any of these ranges.

[0143] In a preferred embodiment, the blend comprises the following ingredients:

[0144] 2-3.5 wt. % of a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid, and / or containing repeating units derived from styrene and repeating units derived from an unsaturated anhydride;

[0145] 2.5-4 wt.% of a polysaccharide (preferably starch); and

[0146] 90-95 wt.% of a wax.

[0147] In an embodiment, the blend comprises 2-3.5 wt.% of the polymer, for example, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, or 3.5 wt.%, or a sub-range consisting of any of these ranges.

[0148] In an embodiment, the blend comprises 2.5-4 wt.% of the polysaccharide (preferably starch), for example, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, or 4.0 wt.%, or a sub-range consisting of any of these ranges.

[0149] In an embodiment, the blend comprises 90-95 wt.% of the wax, for example, 90, 90.5, 91, 91.5, 92, 92.5, 93, 93.5, 94, 94.5, or 95 wt.%, or a sub-range consisting of any of these ranges.

[0150] In an embodiment, the blend comprises 1-2 wt.% of the hydrophilic modifier, for example, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0 wt.%, or a sub-range consisting of any of these ranges. In an embodiment, the amount of hydrophilic modifier is calculated based on a 25 wt.% aqueous ammonium hydroxide solution. When the hydrophilic modifier is not a 25 wt.% aqueous ammonium hydroxide solution, it can be converted to a solution having the same equivalent (hydrogen ion or hydroxide) as a 25 wt.% aqueous ammonium hydroxide solution before calculating the amount of the hydrophilic modifier.

[0151] In a preferred embodiment, the blend comprises the following ingredients:

[0152] 2-3.5 wt.% of a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid, and / or containing repeating units derived from styrene and repeating units derived from an unsaturated anhydride;

[0153] 2.5-4 wt.% of a polysaccharide (preferably starch);

[0154] 90-95 wt.% of a wax; and

[0155] 1-2 wt.% of a hydrophilic modifier.

[0156] In one embodiment, the blend comprises 0.5-1.5 wt.% of the polymer, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 wt.%, or a sub-range consisting of any of these ranges.

[0157] In one embodiment, the blend comprises 0.8-1.8 wt.% of the polysaccharide (preferably starch), for example, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, or 1.8 wt.%, or a sub-range consisting of any of these ranges.

[0158] In one embodiment, the blend comprises 0.1-1 wt.% of the hydrophilic modifier, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 wt.%, or a sub-range consisting of any of these ranges. In one embodiment, the amount of hydrophilic modifier is calculated based on 25 wt.% aqueous ammonium hydroxide solution. When the hydrophilic modifier is not 25 wt.% aqueous ammonium hydroxide solution, it can be converted to a solution having the same equivalent (hydrogen ion or hydroxide) as 25 wt.% aqueous ammonium hydroxide solution before calculating the amount of hydrophilic modifier.

[0159] In one embodiment, the blend comprises 20-40 wt.% of the wax, for example, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40 wt.%, or a sub-range consisting of any of these ranges.

[0160] In one embodiment, the blend comprises 50-75 wt.% of the solvent, for example, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, or 75 wt.%, or a sub-range consisting of any of these ranges.

[0161] In one preferred embodiment, the blend comprises the following ingredients:

[0162] 0.5-1.5 wt.% of a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid, and / or containing repeating units derived from styrene and repeating units derived from an unsaturated anhydride;

[0163] 0.8-1.8 wt.% of a polysaccharide (preferably starch);

[0164] 20-40 wt.% of a wax;

[0165] 0.1-1 wt.% of a hydrophilic modifier; and

[0166] 50-75 wt.% of a solvent.

[0167] In a preferred embodiment, the blend comprises the following ingredients:

[0168] a styrene-maleic anhydride copolymer;

[0169] a cationic amylopectin;

[0170] a Fischer-Tropsch wax;

[0171] 25 wt.% aqueous ammonium hydroxide solution.

[0172] In a preferred embodiment, the blend further comprises water.

[0173] In an embodiment, the blend comprises 2-3.5 wt.% of the styrene-maleic anhydride copolymer, for example, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, or 3.5 wt.%, or a sub-range consisting of any of these ranges.

[0174] In an embodiment, the blend comprises 2.5-4 wt.% of the cationic amylopectin, for example, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, or 4.0 wt.%, or a sub-range consisting of any of these ranges.

[0175] In an embodiment, the blend comprises 90-95 wt.% of the Fischer-Tropsch wax, for example, 90, 90.5, 91, 91.5, 92, 92.5, 93, 93.5, 94, 94.5, or 95 wt.%, or a sub-range consisting of any of these ranges.

[0176] In an embodiment, the blend comprises 1-2 wt.% of the 25 wt.% aqueous ammonium hydroxide solution, for example, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0 wt.%, or a sub-range consisting of any of these ranges.

[0177] In a preferred embodiment, the blend comprises the following ingredients:

[0178] 2-3.5 wt.% of a styrene-maleic anhydride copolymer;

[0179] 2.5-4 wt.% of a cationic amylopectin;

[0180] 90-95 wt.% of a Fischer-Tropsch wax;

[0181] 1-2 wt.% of a 25 wt.% aqueous ammonium hydroxide solution.

[0182] In a preferred embodiment, the blend comprises:

[0183] a styrene-maleic anhydride copolymer;

[0184] a cationic amylopectin;

[0185] a Fischer-Tropsch wax;

[0186] a 25 wt.% aqueous ammonium hydroxide solution; and

[0187] water.

[0188] In an embodiment, the blend comprises 0.5-1.5 wt.% of the styrene-maleic anhydride copolymer, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 wt.%, or a sub-range consisting of any of these ranges.

[0189] In an embodiment, the blend comprises 0.8-1.8 wt.% of the cationic amylopectin, for example, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, or 1.8 wt.%, or a sub-range consisting of any of these ranges.

[0190] In an embodiment, the blend comprises 0.1-1 wt.% of the 25 wt.% aqueous ammonium hydroxide solution, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 wt.%, or a sub-range consisting of any of these ranges.

[0191] In an embodiment, the blend comprises 20-40 wt.% of the Fischer-Tropsch wax, for example, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40 wt.%, or a sub-range consisting of any of these ranges.

[0192] In an embodiment, the blend comprises 50-75 wt.% of the water, for example, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, or 75 wt.%, or a sub-range consisting of any of these ranges.

[0193] In a preferred embodiment, the blend comprises the following ingredients:

[0194] 0.5-1.5 wt.% of a styrene-maleic anhydride copolymer;

[0195] 0.8-1.8 wt.% of cationic amylopectin;

[0196] 20-40 wt.% of Fischer-Tropsch wax;

[0197] 0.1-1 wt.% of a 25 wt.% aqueous ammonium hydroxide solution; and

[0198] 50-75 wt.% of water.

[0199] In an embodiment, the blend comprises 3-15 wt.% of the blend in the wet mould mixture, for example, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 wt.%, or a sub-range consisting of any of these ranges. Preferably, the blend comprises 6-10 wt.% of the blend in the wet mould mixture.

[0200] In another aspect of the application, the application provides a fibre aid comprising any of the blends described herein before, which further comprises at least one of a water repellent agent (e.g., a sizing agent, for example, an Alkyl Ketene Dimer (AKD)) and / or a retention aid.

[0201] In an embodiment, the alkyl group in the AKD can comprise C 18 and C 16 alkyl groups.

[0202] In an embodiment, the proportion of C 18 alkyl groups in the AKD can be 10-90 wt%, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 wt%, or a sub-range consisting of any of these ranges.

[0203] In an embodiment, the proportion of C 16The ratio of the alkyl group can be 10-90 wt.%, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 wt.%, or a sub-range consisting of any of these ranges.

[0204] In one embodiment, the fiber aid can be used as a fiber additive, especially a molded fiber additive. The fiber aid can be used in wet-end molded fibers. The fiber aid can impart good water resistance and / or better oil resistance to the resulting molded fiber product.

[0205] In one embodiment, the retention aid comprises an organic high molecular polymer. Preferably, the retention aid comprises an organic amine / ammonium salt, polyoxyethylene, and derivatives thereof. More preferably, the retention aid comprises polyacrylamide and derivatives thereof, for example, cationic polyacrylamide (CPAM), anionic polyacrylamide (APAM), or non-ionic polyacrylamide (NPAM). Most preferably, the retention aid comprises cationic polyacrylamide (CPAM).

[0206] In one embodiment, the blend does not contain any fluorine-containing substances, for example, does not contain perfluoro and polyfluoro alkyl substances.

[0207] In one embodiment, the blend comprises 5-15 wt.% of the wet mold mixture, for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 wt.%, or a sub-range consisting of any of these ranges. Preferably, the blend comprises 6-10 wt.% of the wet mold mixture.

[0208] In one embodiment, the water repellent agent comprises 1-5 wt.% of the wet mold mixture, for example, 1, 2, 3, 4, or 5 wt.%, or a sub-range consisting of any of these ranges. Preferably, the water repellent agent comprises 2-4 wt.% of the wet mold mixture.

[0209] In one embodiment, the retention aid comprises 0-200 ppm of the wet mold mixture, for example, 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200 ppm, or a sub-range consisting of any of these ranges. Preferably, the retention aid comprises 80-120 ppm of the wet mold mixture.

[0210] In yet another aspect of the present application, a molded (e.g., fiber) product comprising the blend described herein, or the fiber aid described herein is provided.

[0211] In yet another aspect of the application, a method of preparing the blend of the application is provided, comprising the steps of:

[0212] 1) preparing an aqueous phase, said aqueous phase comprising:

[0213] a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated carboxylic acid, and / or a polymer containing repeating units derived from styrene and repeating units derived from an unsaturated anhydride;

[0214] a polysaccharide, preferably starch; and

[0215] water;

[0216] 2) preparing an oil phase, said oil phase comprising: a wax; and

[0217] 3) emulsifying the prepared aqueous phase and oil phase mixture.

[0218] In one embodiment, the polymer is dissolved in an aqueous solution of a hydrophilic modifier.

[0219] In one embodiment, the starch is subjected to a gelatinization process.

[0220] In one embodiment, in step 1), the mixture of the polymer, polysaccharide, preferably starch, and water is heated to a temperature of 80-100°C, for example, 80, 85, 90, 95, or 100°C, or a sub-range consisting of any of these ranges.

[0221] In one embodiment, in step 1), the heating is continued for 60-100 minutes, for example, 60, 70, 80, 90, or 100 minutes, or a sub-range consisting of any of these ranges.

[0222] In one embodiment, in step 2), the wax is heated to a temperature of 80-100°C, for example, 80, 85, 90, 95, or 100°C, or a sub-range consisting of any of these ranges.

[0223] In one embodiment, in step 2), the heating is continued until the wax is completely melted.

[0224] In one embodiment, in step 3), the emulsification of the mixed aqueous phase, oil phase mixture is performed by a homogenization method, a shearing method, and / or an ultrasonic method.

[0225] In one embodiment, in step 3), after the emulsification, the resulting product is subjected to a cooling process. For example, it is cooled to a temperature of 10-35°C.

[0226] In a further aspect of the application, there is provided a wet end mixture comprising the blend of the application.

[0227] In one embodiment, the blend is present in the wet end mixture in a mass percentage of 3-15 wt.%, for example 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15 wt.%, or a sub-range consisting of any of these ranges. Preferably, the blend is present in the wet end mixture in a mass percentage of 6-10 wt.%.

[0228] In one embodiment, the water repellent is present in the wet end mixture in a mass percentage of 1-5 wt.%, for example 1, 2, 3, 4 or 5 wt.%, or a sub-range consisting of any of these ranges. Preferably, the water repellent is present in the wet end mixture in a mass percentage of 2-4 wt.%.

[0229] In one embodiment, the retention aid is present in the wet end mixture in a mass percentage of 0-200 ppm, for example 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190 or 200 ppm, or a sub-range consisting of any of these ranges. Preferably, the retention aid is present in the wet end mixture in a mass percentage of 80-120 ppm.

[0230] In one embodiment, the dry substance is present in the wet end mixture in a mass percentage of 15-25 wt.%, for example 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 wt.%, or a sub-range consisting of any of these ranges. Preferably, the dry substance is present in the wet end mixture in a mass percentage of 18-22 wt.%.

[0231] In a further aspect of the application, there is provided a moulded (e.g. fibre) article made from the wet end mixture of the application.

[0232] In one embodiment, the moulded (e.g. fibre) article is made from the wet end mixture by drying.

[0233] In a further aspect of the application, there is provided the use of the blend of the application as a wet end moulding fibre aid.

[0234] In one embodiment, the blend is present in the wet end mixture in a mass percentage of 3-15 wt.%, for example 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15 wt.%, or a sub-range consisting of any of these ranges. Preferably, the blend is present in the wet end mixture in a mass percentage of 6-10 wt.%.

[0235] In an embodiment, the waterproofing agent is present in the wet mould mixture in a mass percentage of 1-5 wt.%, for example, 1, 2, 3, 4 or 5 wt.%, or a sub-range consisting of any of these ranges. Preferably, the waterproofing agent is present in the wet mould mixture in a mass percentage of 2-4 wt.%.

[0236] In an embodiment, the retention agent is present in the wet mould mixture in a mass percentage of 0-200 ppm, for example, 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190 or 200 ppm, or a sub-range consisting of any of these ranges. Preferably, the retention agent is present in the wet mould mixture in a mass percentage of 80-120 ppm.

[0237] The blend of the present application does not contain any PFAS component, which meets the environmental protection requirements, while avoiding the health risks that PFAS might bring. Moreover, it can be applied in the wet part, which belongs to a non-surface treatment process, and better meets the oil and / or water resistance requirements of the moulded fibre food packaging.

[0238] In the present application, the polysaccharide can include all saccharides other than monosaccharides.

[0239] In the present application, the pulp (e.g. paper pulp) concentration refers to the mass percentage of fibres in the pulp, and the absolute dry pulp (absolute dry fibres) refers to a fibre content of 100%. Since the pulp is diluted to different concentrations in actual production, in the present application, the mass percentage of each component in the wet mould mixture refers to the ratio between the mass of each component added and the mass of the absolute dry pulp converted from the actual pulp (e.g. paper pulp) used.

[0240] In an embodiment, the weight of the absolute dry pulp is obtained by multiplying the weight of the pulp (e.g. paper pulp) by the pulp concentration.

[0241] In the present invention, "wet-mold mixture" refers to the mixture injected into the mold when making food packaging using the molded fiber process, which already contains all the ingredients (e.g., fibers, pulp, various additives, etc.) needed to make the food packaging, and no further ingredients are added to it in the subsequent process. In the present invention, the mass percentage of each ingredient in the wet-mold mixture refers to the ratio between the mass of each ingredient added and the mass of the absolute dry pulp converted from the pulp actually used. The mass of the blend, water repellent, and retention aid added is based on the total mass of the blend, emulsion, or solution (not based on the active ingredients). In one embodiment, the mass percentage of the water repellent in the wet-mold mixture is calculated based on an AKD emulsion with a solid content of 12.5%. If calculated based on the active ingredients, the mass percentage of the water repellent in the wet-mold mixture can be 0.125-0.625 wt.%, for example, 0.125, 0.225, 0.325, 0.425, 0.525, or 0.625 wt.%, or a sub-range consisting of any of these ranges. In one embodiment, the mass percentage of the retention aid in the wet-mold mixture is calculated based on a CPAM solution with a concentration of 15 wt.%. If calculated based on the active ingredients, the mass percentage of the retention aid in the wet-mold mixture can be 0-30 ppm, for example, 0, 5, 10, 15, 20, 25, or 30 ppm, or a sub-range consisting of any of these ranges.

[0242] In the present invention, "dry matter" refers to the sum of all the substances left after the final drying process of the "wet-mold mixture".

[0243] In the present invention, "room temperature" refers to a temperature of 10-35 °C.

[0244] In the present invention, the wet section can include any process step before the molded fibers are dried.

[0245] The blend described herein can also be referred to as a mixture, a mix, or a composition. One or more components (or ingredients) of the blend described herein can be in one or more separate parts (e.g., an oil phase and an aqueous phase), or made from one or more separate parts (e.g., an oil phase and an aqueous phase). One or more components of the blend described herein can or can not undergo a chemical reaction.

[0246] "Molding" described herein can also be referred to as "molding" and refers to a method of shaping fibers through a mold.

[0247] "Wet section molded fibers" described herein refer to a wet pulp with a certain concentration of fibers before shaping, which can or can not be further added with other ingredients (e.g., the blend described herein). The wet pulp can also be referred to as a slurry. The "blend" described in the present invention can be directly added to the "wet section molded fibers".

[0248] The term "fiber" as used herein refers to any fiber known in the art that can be used for molding, such as sugarcane fiber, bamboo fiber, or wood fiber.

[0249] As used herein, “substitution” means that any one or more hydrogen atoms on a specified atom or group are replaced by a portion selected from the indicated group, provided that the replacement does not exceed the normal valence of the specified atom.

[0250] "alkyl" is a branched or straight-chain saturated aliphatic hydrocarbon group. In one embodiment, the alkyl group contains 1 to about 20 carbon atoms, more typically 1 to about 12 carbon atoms, 1 to about 6 carbon atoms, or 1 to about 4 carbon atoms. In one embodiment, the alkyl group contains 1 to about 8 carbon atoms. In some embodiments, the alkyl group is C1-C2, C1-C3, or C1-C6. As used herein, the specified range refers to each member of the range as an alkyl group of a separate kind. For example, as used herein, the term C1-C6... 20 Alkyl refers to a straight-chain or branched alkyl group having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 carbon atoms, and is intended to refer to each of these as a separate species. For example, as used herein, the term C1-C4 alkyl refers to a straight-chain or branched alkyl group having 1, 2, 3, or 4 carbon atoms, and is intended to refer to each of these as a separate species. When C0-C n When an alkyl group is used herein in conjunction with another group, such as (C3-C7 cycloalkyl)CO-C4 alkyl or -CO-C4 alkyl (C3-C7 cycloalkyl), the indicated group—in this case cycloalkyl—is either directly bonded by a single covalent bond (CO alkyl) or linked by an alkyl chain (in this case 1, 2, 3, or 4 carbon atoms). Alkyl groups may also be linked via other groups such as heteroatoms, as in -O-CO-C4 alkyl (C3-C7 cycloalkyl). Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In one embodiment, the alkyl group is optionally substituted as described above.

[0251] "Alkenyl" is a branched or straight-chain aliphatic hydrocarbon group having one or more carbon-carbon double bonds, which may occur at a stable point along the chain. Non-limiting examples include C2-C8 alkenyl, C2-C6 alkenyl, and C2-C4 alkenyl. As used herein, the specified scope refers to each member of the scope as an alkenyl group of a separate kind, as described above with respect to the alkyl portion. For example, as used herein, the term C1-C... 20Alkenyl refers to a straight-chain or branched-chain alkenyl group having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 carbon atoms and is intended to refer to each of these as an independent species. Examples of alkenyl groups include, but are not limited to, ethenyl and propenyl. In one embodiment, the alkenyl group is optionally substituted as described above.

[0252] “Alkynyl” is a branched or straight-chain aliphatic hydrocarbon group having one or more carbon-carbon triple bonds, which triple bond can occur at any stable point along the chain, for example, C2-C8alkynyl or C2-C6alkynyl. As used herein, the specified range refers to each member of the range as an independent species of alkynyl group as described above. For example, as used herein, the term C1-C 20 Alkynyl refers to a straight-chain or branched-chain alkynyl group having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 carbon atoms and is intended to refer to each of these as an independent species. Examples of alkynyl groups include, but are not limited to, ethynyl, propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 1-hexynyl, 2-hexynyl, 3-hexynyl, 4-hexynyl, and 5-hexynyl. In one embodiment, the alkynyl group is optionally substituted as described above.

[0253] “Hydrocarbyl” is a branched or straight-chain saturated, unsaturated aliphatic group. The hydrocarbyl group can be an alkyl, alkenyl, or alkynyl group. As used herein, the specified range refers to each member of the range as an independent group. For example, as used herein, the term C1-C 30 Hydrocarbyl refers to a hydrocarbyl having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 carbon atoms and is intended to refer to each of these as an independent species.

[0254] “Cycloalkyl” is a saturated or unsaturated alkyl group containing a ring structure. For example, as used herein, the term C3-C6cycloalkyl or C3-C7cycloalkyl refers to an alkyl group including 1-2 rings, each of which can contain 3, 4, 5, or 6, or 3, 4, 5, 6, or 7 carbon atoms, which can contain branching, which can contain carbon-carbon double or triple bonds. Examples of “cycloalkyl” include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, and phenyl, among others. In one embodiment, the alkyl group is optionally substituted as described above.

[0255] The percentages, ratios, proportions, amounts or parts stated in the present application are by weight unless otherwise specified.

[0256] The numerical values stated in the present application can be approximate values after rounding. DETAILED DESCRIPTION

[0257] For better understanding of the present application, the following further illustrates the present application with examples, but the present application is not limited to the following examples. The experimental operations stated in the following examples are all routine operations unless otherwise specified; the reagents and materials stated in the following examples are all commercially available unless otherwise specified.

[0258] 1. Preparation of a blend product for oil and grease resistant (OGR) molded fibers

[0259] 1) Preparation of the aqueous phase. 9 g of styrene-maleic anhydride copolymer (weight average molecular weight of 30000 Da, molar ratio of repeating units derived from styrene to repeating units derived from maleic anhydride of 2:1) was dissolved in 4 g of 25 wt.% aqueous ammonium hydroxide solution. 12 g of cationic waxy corn starch (degree of substitution of 0.02-0.3) was gelatinized in water. The resulting SMA solution, starch solution and water were placed together in a vessel and heated to 90 °C for about 90 minutes. The total amount of water used was 675 g.

[0260] 2) Preparation of the oil phase. 300 g of Fischer-Tropsch wax (freezing point between 75-80 °C) was heated to 90 °C in a vessel until it was completely melted.

[0261] 3) The aqueous phase and the oil phase were mixed. The mixture was emulsified by a high-speed shearing machine (operating at 20000 rpm for 5 minutes) and a homogenizer (manufacturer: GEA; model: TwinPANDA 600; operating pressure 200-260 Pa). It was then cooled to room temperature for later use.

[0262] 2. Preparation of a molded fiber tray

[0263] A molded tray with a standard weight of 11 g (350 gsm) was prepared using the existing molded fiber process. It mainly included the following steps: raw material preparation, slurry preparation, molding and drying. The raw material used was 360 mL of paper pulp composed of 80% sugar cane fiber pulp and 20% wood fiber NBKP (Needle-lief tree Breached Kraft Pulp, bleached kraft pulp of coniferous wood), and the concentration of the paper pulp was 3% (i.e. the mass ratio of the material in the paper pulp excluding water). It was equivalent to 11 g of absolute dry pulp. After dilution to 1%, an AKD emulsion (solid content of 12.5%, C18 65 wt. % C 16 35 wt. %) and OGR, and other additives needed to be added in the existing molded fiber process. In addition, 15 wt. % CPAM solution was further added as a retention aid for some products. Then, the pulp concentration was further diluted to 0.3% by stirring for 2-5 minutes. In the molding stage, the hot-press temperature was 150 °C, the pressure was 0.4 MPa, and the hot-press time was 60 s. The specific conditions for making each tray are shown in Table 1 below.

[0264] Table 1 Summary of the conditions for making molded fiber trays

[0265] Note:

[0266] 1. The wet mix weight in the table refers to the weight of the wet mix injected into the mold.

[0267] 2. The dry mix weight in the table refers to the weight of the wet mix after final drying, which can also be referred to as the dry matter weight.

[0268] Subsequent waterproof and oil-proof tests were conducted on each tray.

[0269] Test Example 1 Oil-proof test against room temperature oil

[0270] The oil-proof test was conducted on trays numbered 1-1, 2-1, 3-1, 4-1, 5-1, and 6-1. The specific operation method was as follows: the front side (the side for holding food) of each tray was placed upward on a paper towel, and then an equal amount (about 60 mL each) of room temperature corn oil was poured onto the front side of each tray (covering the entire bottom of the tray), and after 30 and 60 minutes, the paper towel was observed for oil stains. The specific results are shown in Table 2 below.

[0271] Table 2 Oil-proof test results against room temperature oil

[0272] Test Example 2 Oil-proof test against 60 °C oil

[0273] The oil-proof test was conducted on tray numbered 1-2. The specific operation method was as follows: the front side (the side for holding food) of the tray was placed upward on a paper towel, and then about 60 mL of 60 °C corn oil was poured onto the front side of the tray (covering the entire bottom of the tray), and after 30 and 60 minutes, the paper towel was observed for oil stains. The specific results are shown in Table 3 below.

[0274] Table 3 Oil-proof test results against 60 °C oil

[0275] Test Example 3 Oil-proof test against 70 °C oil

[0276] The oil-proof test was carried out on the trays numbered 1-3, 2-2, 3-2, 5-2, 6-2 and 7-2. The specific operation method was as follows: each tray was placed upside down on a paper towel, and then an equal amount (about 60 mL each) of 70℃ corn oil was poured into the front side of each tray (covering the entire bottom of the tray), and after 30, 60 minutes, the paper towel was observed for oil stains. The specific results are shown in Table 4 below.

[0277] Table 4 Oil-proof test results for 70℃ oil

[0278] Test Example 4 Water-proof test for 95℃ water

[0279] The water-proof test was carried out on the trays numbered 2-3, 3-3, 4-3, 5-3, 6-3 and 7-3. The specific operation method was as follows: each tray was placed upside down on a paper towel, and then an equal amount (about 60 mL each) of 95℃ water was poured into the front side of each tray (covering the entire bottom of the tray), and after 30, 60 minutes, the paper towel was observed for water stains. The specific results are shown in Table 5 below.

[0280] Table 5 Water-proof test results for 95℃ water

[0281] From the results of the above test examples, it can be seen that when 6-10% of the OGR product of the present application is added, each tray has good oil-proof effect; and on this basis, at the same time, 3% of AKD emulsion is added, which can make the tray have good water-proof and oil-proof effect at the same time, and the water-proof and / or oil-proof performance of the tray can meet the market demand (usually requires that water and / or oil cannot penetrate the food packaging within 30 minutes). Moreover, by comparing the oil-proof performance of the products numbered 4-1 and 6-1 in Test Example 1, it can be found that the addition of a retention aid can further improve the oil-proof effect of the OGR product of the present application.

Claims

1. A blend comprising: a polymer, the polymer containing repeat units derived from styrene and repeat units derived from an unsaturated carboxylic acid and / or repeat units derived from an unsaturated anhydride; a polysaccharide (preferably starch); a wax; and optionally a hydrophilic modifier.

2. The blend of claim 1, the hydrophilic modifier comprising ammonium hydroxide, sodium hydroxide, and / or potassium hydroxide; preferably, the hydrophilic modifier comprises ammonium hydroxide. More preferably, the ammonium hydroxide is a 10-30 wt.% ammonium hydroxide aqueous solution; most preferably, the hydrophilic modifier comprises a 25 wt.% ammonium hydroxide aqueous solution.

3. The blend of any of the preceding claims, wherein, The repeating units derived from styrene have the following structural formula: Among them, R 1 R 2 and R 3 Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl. * denotes a point of attachment; and / or The repeating units derived from unsaturated acid anhydrides have the following structural formula: Among them, R 4 and R 5 Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl. * denotes a point of attachment; and / or The repeating units derived from unsaturated acid anhydrides have the following structural formula: Among them, R 6 and R 7 Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl. either of M and M', in each occurrence, is independently selected from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ), or H + , * denotes a point of attachment; and / or The repeating units derived from unsaturated carboxylic acids have the following structural formula: Among them, R 8 R 9 and R 10 Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl. M" is independently selected at each occurrence thereof from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ), or H + , * denotes a point of attachment; and / or The repeating units derived from unsaturated carboxylic acids have the following structural formula: wherein R is selected from the group consisting of H, unsubstituted C1-C6alkyl, substituted C1-C6alkyl, unsubstituted C2-C6alkenyl, substituted C2-C6alkenyl, unsubstituted C2-C6alkynyl, or substituted C2-C6alkynyl, the substituents being selected from the group consisting of carboxyl, hydroxyl, C3-C6cycloalkyl, C1-C6alkoxy, amino, mono- or di-C1-C6alkylamino, nitro, thiol, C2-C6alkenyl, or C2-C6alkynyl, 11 independently at each occurrence thereof, is selected from the group consisting of H, unsubstituted C1-C6alkyl, substituted C1-C6alkyl, unsubstituted C2-C6alkenyl, substituted C2-C6alkenyl, unsubstituted C2-C6alkynyl, or substituted C2-C6alkynyl, the substituents being selected from the group consisting of carboxyl, hydroxyl, C3-C6cycloalkyl, C1-C6alkoxy, amino, mono- or di-C1-C6alkylamino, nitro, thiol, C2-C6alkenyl, or C2-C6alkynyl, M'" is independently selected at each occurrence thereof from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ), or H + , * denotes a point of attachment.

4. The blend of any preceding claim, further comprising a solvent, e.g., water, e.g., distilled water, e.g., double distilled water.

5. The blend of any of the preceding claims, the polymer having a structural formula comprising the following repeat units: wherein, R 1 , R 2 , R 3 , R 4 , and R 5 are each, at each occurrence, independently selected from H, unsubstituted C1-C6alkyl, substituted C1-C6alkyl, unsubstituted C2-C6alkenyl, substituted C2-C6alkenyl, unsubstituted C2-C6alkynyl, or substituted C2-C6alkynyl, the substituents being selected from carboxyl, hydroxyl, C3-C6cycloalkyl, C1-C6alkoxy, amino, mono- or di-C1-C6alkylamino, nitro, thiol, C2-C6alkenyl, or C2-C6alkynyl, the molar ratio of a and b is 1 : 1 to 6: 1, preferably 2: 1 to 3: 1, denotes a direct or indirect attachment; or The polymer has a structural formula comprising the following repeat unit: Among them, R 1 R 2 R 3 R 6 and R 7 Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl. either of M and M', in each occurrence, is independently selected from an alkali metal ion (e.g., Na + , K + ), an ammonium ion (NH4 + ), or H + , the molar ratio of a and c is 1 : 1 to 6: 1, preferably 2: 1 to 3: 1, denotes a direct or indirect attachment; or, The polymer has a structural formula comprising the following repeat unit: Among them, R 1 R 2 R 3 R 8 R 9 and R 10 Each of the following, in each occurrence, is independently selected from H, unsubstituted C1-C6 alkyl, substituted C1-C6 alkyl, unsubstituted C2-C6 alkenyl, substituted C2-C6 alkenyl, unsubstituted C2-C6 ynyl, or substituted C2-C6 ynyl, wherein the substituent is selected from carboxyl, hydroxyl, C3-C6 cycloalkyl, C1-C6 alkoxy, amino, mono- or di-C1-C6 alkylamino, nitro, thiol, C2-C6 alkenyl, or C2-C6 ynyl. "M" is independently selected from alkali metal ions (e.g., Na) in each occurrence. + K + ), ammonium ions (NH4) + ) or H + , the molar ratio of a and d is 1 : 1 to 6: 1, preferably 2: 1 to 3: 1, denotes a direct or indirect attachment; or, The polymer has a structural formula comprising the following repeat unit: wherein, in any of R 1 , R 2 , R 3 , and R 11 , at each occurrence, is independently selected from H, unsubstituted C1-C6alkyl, substituted C1-C6alkyl, unsubstituted C2-C6alkenyl, substituted C2-C6alkenyl, unsubstituted C2-C6alkynyl, or substituted C2-C6alkynyl, the substituents being selected from carboxy, hydroxy, C3-C6cycloalkyl, C1-C6alkoxy, amino, mono- or di-C1-C6alkylamino, nitro, thiol, C2-C6alkenyl, or C2-C6alkynyl, M”' is independently selected from alkali metal ions (e.g., Na) each time it appears. + K + ), ammonium ions (NH4) + ) or H + , the molar ratio of a and d is 1 : 1 to 6: 1, preferably 2: 1 to 3: 1, denotes a direct or indirect attachment; or Preferably, the polymer comprises a styrene-maleic anhydride copolymer (SMA).

6. The blend of any preceding claim, the polymer having a weight average molecular weight of 1000-100000 Da; preferably, the polymer has a weight average molecular weight of 5000-30000 Da.

7. The blend of any preceding claim, the molar ratio of repeat units derived from styrene to repeat units derived from an unsaturated anhydride and / or repeat units derived from an unsaturated carboxylic acid in the polymer is 1 : 1 to 6: 1, e.g., 1 : 1, 1.5: 1, 2: 1, 2.5: 1, 3: 1, 3.5: 1, 4: 1, 4.5: 1, 5: 1, 5.5: 1, or 6: 1, or a sub-range consisting of any of these ranges; preferably, the molar ratio thereof is 2: 1 to 3:

1.

8. The blend of any preceding claim, the starch comprising a modified starch; preferably, the modified starch comprises a cationic starch; more preferably, the starch comprises a cationic amylopectin, e.g., a cationic waxy corn starch.

9. The blend of any preceding claim, the wax having a freezing point of less than or equal to 120 °C; preferably, the wax has a freezing point of greater than or equal to 50 °C and less than or equal to 100 °C; most preferably, the wax has a freezing point of greater than or equal to 70 °C and less than or equal to 85 °C.

10. The blend of any of the preceding claims, the wax comprising a natural wax and / or a synthetic wax; preferably, the wax comprises a polypropylene wax, a polyamide wax, an oxidized polyethylene wax, a polyethylene wax, a Fischer-Tropsch wax, and / or a biomass-based wax; more preferably, the wax comprises a Fischer-Tropsch wax.

11. A fiber adjunct comprising the blend of any of claims 1-10 and at least one of a water repellent (e.g., alkyl ketene dimer) and a retention aid.

12. The fiber adjunct of claim 11, wherein, the retention aid comprises an organic polymeric polymer; preferably, the retention aid comprises an organic amine / ammonium salt, polyoxyethylene and derivatives thereof; more preferably, the retention aid comprises a polyacrylamide and derivatives thereof, such as a cationic polyacrylamide (CPAM), an anionic polyacrylamide (APAM), or a non-ionic polyacrylamide (NPAM); most preferably, the retention aid comprises a cationic polyacrylamide (CPAM).

13. A wet mix comprising the blend of any one of claims 1 to 10, or the fiber adjunct of any one of claims 11 to 12, wherein: The dry substance comprises 15-25 wt.%, preferably 18-22 wt.% of the mass of the wet mould mixture.

14. The wet mold mixture of claim 13, wherein, The blend comprises 3-15 wt.% of the mass of the wet mould mixture; preferably, the blend comprises 6-10 wt.% of the mass of the wet mould mixture.

15. A molded fibrous article comprising the blend of any of claims 1-10.

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