Environment-friendly straw and preparation method thereof

Abstract

The invention relates to the technical field of environment-friendly straws, in particular to an environment-friendly straw and a preparation method thereof.The environment-friendly straw is prepared from outer-layer paper, middle-layer paper and inner-layer paper in a spiral winding mode, the outer-layer paper and the inner-layer paper are both food-grade bamboo pulp paper, the inner-layer paper is PLA coated paper, the middle-layer paper is bonded with the outer-layer paper and the inner-layer paper through food-grade bonding glue, and the inner-layer paper is bonded with the middle-layer paper through food-grade bonding glue. The surface, away from the middle-layer paper, of the outer-layer paper and the surface, away from the middle-layer paper, of the inner-layer paper are both coated with food-grade adhesive glue. The preparation method of the environment-friendly straw comprises the following steps: S1, preparing materials; s2, preparing glue; s3, manufacturing a pipe; and S4, cutting. The environment-friendly straw is biodegradable, the preparation process is simple and easy to implement, the food-grade adhesive in the formula has the functions of an adhesive and a high-temperature-resistant waterproof blocking agent, good structural strength is provided for forming of the environment-friendly straw, and good isolation protection is provided for use of the environment-friendly straw in a high-temperature environment.

Description

Technical Field

[0001] The invention relates to the technical field of environmentally friendly straws, in particular to an environmentally friendly straw and a preparation method thereof. Background Art

[0002] Paper straws are made from paper processed from wood pulp or other plant fibers as the main raw material. They are composed of 3 to 5 layers of food-grade paper with different specifications, weight and water resistance. They are waterproof coated and spirally wrapped on one side. Each layer of paper is bonded together with food-grade glue to form a spiral tube.

[0003] The Chinese invention patent with publication number CN110714363B discloses a paper straw and a method for making the same, which uses an edible wax layer as a coating layer on the inner side of the first paper layer and the outer side of the second paper layer. Generally speaking, the melting temperature of edible wax is usually between 60°C and 80°C, so it is not suitable for beverages with a temperature higher than 80°C. In addition, edible wax is difficult to completely dissolve or evenly disperse in beverages, which may affect the taste of the beverage, bringing a greasy or unnatural feeling, thereby affecting the drinking experience. Summary of the invention

[0004] The object of the present invention is to provide an environmentally friendly straw and a preparation method thereof to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, on the one hand, the present invention provides the following technical solutions: an environmentally friendly straw, wherein the environmentally friendly straw is made of an outer layer of paper, a middle layer of paper and an inner layer of paper in a spirally wound manner, wherein the outer layer of paper and the inner layer of paper are both food-grade bamboo pulp paper, and the inner layer of paper is PLA coated paper, and the middle layer of paper is respectively bonded to the outer layer of paper and the inner layer of paper by food-grade adhesive, and the surface of the outer layer of paper away from the middle layer of paper and the surface of the inner layer of paper away from the middle layer of paper are both coated with food-grade adhesive; The food-grade adhesive comprises the following components by mass: 30 parts of food-grade bamboo-based nanocellulose, 9-12 parts of high-acyl gellan gum, 9-12 parts of hydroxypropyl methylcellulose, 5-8 parts of mannoesters, 2-5 parts of food-grade tannic acid, 2-5 parts of linseed oil, 2-5 parts of tragacanth gum powder, 1-2 parts of celery polysaccharide, 1-2 parts of sorbitol, 0.5-1.0 parts of tea polyphenols and 20-25 parts of deionized water.

[0006] Optionally, the gram weight ratio of the outer layer of paper, the middle layer of paper and the inner layer of paper is 1:1.2:1, and the thickness ratio of the outer layer of paper, the middle layer of paper and the inner layer of paper is 1:1:1.

[0007] Optionally, the average width of the food-grade bamboo-based nanocellulose is 5 to 20 nm, the specific surface area of ​​the food-grade bamboo-based nanocellulose is 150 to 300 m² / g, and the tensile strength of the food-grade bamboo-based nanocellulose is 100 to 200 MPa.

[0008] Optionally, the amide value of the high acyl gellan gum is 20-25, the viscosity of the hydroxypropyl methylcellulose is 4000-6500 mPa·s, and the mass ratio of the high acyl gellan gum to the hydroxypropyl methylcellulose is 1:1.

[0009] On the other hand, the present invention also provides a method for preparing the above-mentioned environmentally friendly straw, comprising the following steps: S1. Material preparation: Cut the outer layer paper, the middle layer paper and the inner layer paper into paper strips with a width of 10 mm; S2, glue preparation: bamboo-based nanocellulose, high acyl gellan gum, hydroxypropyl methylcellulose and deionized water are mixed, and efficiently dispersed under ultrasonic stirring to obtain a dispersion liquid, and then mannosyl ester, food-grade tannic acid, linseed oil, tragacanth gum powder, herba schoenoprasum polysaccharides, sorbitol and tea polyphenols are sequentially added to the dispersion liquid, and stirred evenly to obtain a food-grade adhesive; S3, tube making: heating the food-grade adhesive to 40-50°C, first spirally winding the inner paper into a circular tube structure, then applying the food-grade adhesive on the inner and outer sides of the inner paper, then spirally winding the middle paper into a circular tube structure on the outer side of the inner paper, and applying the food-grade adhesive on the outer side of the middle paper, then spirally winding the outer paper into a circular tube structure on the outer side of the middle paper, and finally applying the food-grade adhesive on the outer side of the outer paper, drying, and obtaining a paper tube; S4. Cutting: Feed the paper tube into the straw beveling machine to cut out beveled cuts to obtain environmentally friendly straws.

[0010] Optionally, the spiral winding angles of the outer layer of paper, the middle layer of paper and the inner layer of paper are all 45°, the length of the environmentally friendly straw is 197 mm, and the caliber of the environmentally friendly straw is one of 8 mm, 10 mm and 12 mm.

[0011] Optionally, the thickness of the food-grade adhesive located on the inner side of the inner layer of paper and on the outer side of the outer layer of paper is 0.04-0.06 mm, and the thickness of the food-grade adhesive located on both the inner and outer sides of the middle layer of paper is 0.1-0.3 mm.

[0012] Compared with the prior art, the present invention has the following beneficial effects: the present invention is biodegradable, the preparation process is simple and easy, and the food-grade adhesive in the formula has the functions of both an adhesive and a high-temperature resistant and waterproof barrier agent, which not only provides good structural strength for the molding of environmentally friendly straws, but also provides good isolation protection for the use of environmentally friendly straws in high temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the environmentally friendly straw of the present invention.

[0014] In the figure: 1. inner layer of paper; 2. middle layer of paper; 3. outer layer of paper; 4. food-grade adhesive; 5. food-grade adhesive; 6. food-grade adhesive; 7. food-grade adhesive. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] Embodiment 1: The present invention provides an environmentally friendly straw, which is made of an outer layer of paper, a middle layer of paper and an inner layer of paper in a spiral winding manner, wherein the outer layer of paper and the inner layer of paper are both food-grade bamboo pulp paper, the inner layer of paper is PLA coated paper, the middle layer of paper is respectively bonded to the outer layer of paper and the inner layer of paper by a food-grade adhesive, and the surface of the outer layer of paper away from the middle layer of paper and the surface of the inner layer of paper away from the middle layer of paper are both coated with food-grade adhesive; The food-grade adhesive includes the following components by mass: 30 parts of food-grade bamboo-based nanocellulose, 9 parts of high-acyl gellan gum, 9 parts of hydroxypropyl methylcellulose, 5 parts of mannoesters, 2 parts of food-grade tannic acid, 2 parts of linseed oil, 2 parts of tragacanth gum powder, 1 part of angelica polysaccharide, 1 part of sorbitol, 0.5 parts of tea polyphenols and 20 parts of deionized water.

[0017] The present invention also provides a method for preparing the environmentally friendly straw, comprising the following steps: S1. Material preparation: Cut the outer layer paper, the middle layer paper and the inner layer paper into paper strips with a width of 10 mm; S2, glue preparation: bamboo-based nanocellulose, high acyl gellan gum, hydroxypropyl methylcellulose and deionized water are mixed, and efficiently dispersed under ultrasonic stirring to obtain a dispersion liquid, and then mannosyl ester, food-grade tannic acid, linseed oil, tragacanth gum powder, herba schoenoprasum polysaccharides, sorbitol and tea polyphenols are sequentially added to the dispersion liquid, and stirred evenly to obtain a food-grade adhesive; S3, tube making: heating the food-grade adhesive to 40°C, first spirally winding the inner paper into a circular tube structure, then applying the food-grade adhesive on the inner and outer sides of the inner paper, then spirally winding the middle paper into a circular tube structure on the outer side of the inner paper, and applying the food-grade adhesive on the outer side of the middle paper, then spirally winding the outer paper into a circular tube structure on the outer side of the middle paper, and finally applying the food-grade adhesive on the outer side of the outer paper, drying, and obtaining a paper tube; S4. Cutting: Feed the paper tube into the straw beveling machine to cut out beveled cuts to obtain environmentally friendly straws.

[0018] Embodiment 2: The present invention provides an environmentally friendly straw, which is made of an outer layer of paper, a middle layer of paper and an inner layer of paper in a spiral winding manner, wherein the outer layer of paper and the inner layer of paper are both food-grade bamboo pulp paper, the inner layer of paper is PLA coated paper, the middle layer of paper is respectively bonded to the outer layer of paper and the inner layer of paper by food-grade adhesive, and the surface of the outer layer of paper away from the middle layer of paper and the surface of the inner layer of paper away from the middle layer of paper are both coated with food-grade adhesive; The food-grade adhesive includes the following components by mass: 30 parts of food-grade bamboo-based nanocellulose, 10 parts of high-acyl gellan gum, 10 parts of hydroxypropyl methylcellulose, 6 parts of mannoesters, 3 parts of food-grade tannic acid, 3 parts of linseed oil, 3 parts of tragacanth gum powder, 1.5 parts of angelica polysaccharide, 1.5 parts of sorbitol, 0.7 parts of tea polyphenols and 22 parts of deionized water.

[0019] The present invention also provides a method for preparing the environmentally friendly straw, comprising the following steps: S1. Material preparation: Cut the outer layer paper, the middle layer paper and the inner layer paper into paper strips with a width of 10 mm; S2, glue preparation: bamboo-based nanocellulose, high acyl gellan gum, hydroxypropyl methylcellulose and deionized water are mixed, and efficiently dispersed under ultrasonic stirring to obtain a dispersion liquid, and then mannosyl ester, food-grade tannic acid, linseed oil, tragacanth gum powder, herba schoenoprasum polysaccharides, sorbitol and tea polyphenols are sequentially added to the dispersion liquid, and stirred evenly to obtain a food-grade adhesive; S3, tube making: heating the food-grade adhesive to 44°C, first spirally winding the inner paper into a circular tube structure, then applying the food-grade adhesive on the inner and outer sides of the inner paper, then spirally winding the middle paper into a circular tube structure on the outer side of the inner paper, and applying the food-grade adhesive on the outer side of the middle paper, then spirally winding the outer paper into a circular tube structure on the outer side of the middle paper, and finally applying the food-grade adhesive on the outer side of the outer paper, drying, and obtaining a paper tube; S4. Cutting: Feed the paper tube into the straw beveling machine to cut out beveled cuts to obtain environmentally friendly straws.

[0020] Embodiment 3: The present invention provides an environmentally friendly straw, which is made of an outer layer of paper, a middle layer of paper and an inner layer of paper in a spiral winding manner, wherein the outer layer of paper and the inner layer of paper are both food-grade bamboo pulp paper, the inner layer of paper is PLA coated paper, the middle layer of paper is respectively bonded to the outer layer of paper and the inner layer of paper by food-grade adhesive, and the surface of the outer layer of paper away from the middle layer of paper and the surface of the inner layer of paper away from the middle layer of paper are both coated with food-grade adhesive; The food-grade adhesive includes the following components by mass: 30 parts of food-grade bamboo-based nanocellulose, 11 parts of high-acyl gellan gum, 11 parts of hydroxypropyl methylcellulose, 7 parts of mannoesters, 4 parts of food-grade tannic acid, 4 parts of linseed oil, 4 parts of tragacanth gum powder, 1.8 parts of angelica polysaccharide, 1.8 parts of sorbitol, 0.8 parts of tea polyphenols and 24 parts of deionized water.

[0021] The present invention also provides a method for preparing the environmentally friendly straw, comprising the following steps: S1. Material preparation: Cut the outer layer paper, the middle layer paper and the inner layer paper into paper strips with a width of 10 mm; S2, glue preparation: bamboo-based nanocellulose, high acyl gellan gum, hydroxypropyl methylcellulose and deionized water are mixed, and efficiently dispersed under ultrasonic stirring to obtain a dispersion liquid, and then mannosyl ester, food-grade tannic acid, linseed oil, tragacanth gum powder, herba schoenoprasum polysaccharides, sorbitol and tea polyphenols are sequentially added to the dispersion liquid, and stirred evenly to obtain a food-grade adhesive; S3, tube making: heating the food-grade adhesive to 48°C, first spirally winding the inner paper into a circular tube structure, then applying the food-grade adhesive on the inner and outer sides of the inner paper, then spirally winding the middle paper into a circular tube structure on the outer side of the inner paper, and applying the food-grade adhesive on the outer side of the middle paper, then spirally winding the outer paper into a circular tube structure on the outer side of the middle paper, and finally applying the food-grade adhesive on the outer side of the outer paper, drying, and obtaining a paper tube; S4. Cutting: Feed the paper tube into the straw beveling machine to cut out beveled cuts to obtain environmentally friendly straws.

[0022] Embodiment 4: The present invention provides an environmentally friendly straw, which is made of an outer layer of paper, a middle layer of paper and an inner layer of paper in a spiral winding manner, the outer layer of paper and the inner layer of paper are both food-grade bamboo pulp paper, the inner layer of paper is PLA coated paper, the middle layer of paper is respectively bonded to the outer layer of paper and the inner layer of paper by food-grade adhesive, and the surface of the outer layer of paper away from the middle layer of paper and the surface of the inner layer of paper away from the middle layer of paper are both coated with food-grade adhesive; The food-grade adhesive includes the following components by mass: 30 parts of food-grade bamboo-based nanocellulose, 12 parts of high-acyl gellan gum, 12 parts of hydroxypropyl methylcellulose, 8 parts of mannoesters, 5 parts of food-grade tannic acid, 5 parts of linseed oil, 5 parts of tragacanth gum powder, 2 parts of angelica polysaccharide, 2 parts of sorbitol, 1.0 part of tea polyphenols and 25 parts of deionized water.

[0023] The present invention also provides a method for preparing the environmentally friendly straw, comprising the following steps: S1. Material preparation: Cut the outer layer paper, the middle layer paper and the inner layer paper into paper strips with a width of 10 mm; S2, glue preparation: bamboo-based nanocellulose, high acyl gellan gum, hydroxypropyl methylcellulose and deionized water are mixed, and efficiently dispersed under ultrasonic stirring to obtain a dispersion liquid, and then mannosyl ester, food-grade tannic acid, linseed oil, tragacanth gum powder, herba schoenoprasum polysaccharides, sorbitol and tea polyphenols are sequentially added to the dispersion liquid, and stirred evenly to obtain a food-grade adhesive; S3, tube making: heating the food-grade adhesive to 50°C, first spirally winding the inner paper into a circular tube structure, then applying the food-grade adhesive on the inner and outer sides of the inner paper, then spirally winding the middle paper into a circular tube structure on the outer side of the inner paper, and applying the food-grade adhesive on the outer side of the middle paper, then spirally winding the outer paper into a circular tube structure on the outer side of the middle paper, and finally applying the food-grade adhesive on the outer side of the outer paper, drying, and obtaining a paper tube; S4. Cutting: Feed the paper tube into the straw beveling machine to cut out beveled cuts to obtain environmentally friendly straws.

[0024] In Examples 1 to 4, the gram weight ratio of the outer paper, the middle paper and the inner paper is 1:1.2:1, and the thickness ratio of the outer paper, the middle paper and the inner paper is 1:1:1. The spiral winding angles of the outer paper, the middle paper and the inner paper are all 45°, and the PLA coated paper is a composite material in which PLA is coated on the surface of food-grade single-gloss white kraft paper by a casting machine. The length of the environmentally friendly straw is 197 mm, and the diameter of the environmentally friendly straw is 8 mm. The thickness of the food-grade adhesive located on the inner side of the inner paper and on the outer side of the outer paper is 0.05 mm, and the thickness of the food-grade adhesive located on both sides of the inner and outer sides of the middle paper is 0.2 mm.

[0025] In addition, the average width of food-grade bamboo-based nanocellulose is 5-20 nm, the specific surface area of ​​food-grade bamboo-based nanocellulose is 150-300 m² / g, and the tensile strength of food-grade bamboo-based nanocellulose is 100-200 MPa. The amide value of high acyl gellan gum is 20-25, the viscosity of hydroxypropyl methylcellulose is 4000-6500 mPa·s, and the mass ratio of high acyl gellan gum to hydroxypropyl methylcellulose is 1:1.

[0026] Test Example 1: Straw Intrinsic Quality Test Test content: According to GB / T 44833, the environmentally friendly straws prepared in Examples 1 to 4 were subjected to a stiffness test. The test results are recorded in Table 1.

[0027] Table 1

[0028] As shown in Table 1, the dry stiffness of the environmentally friendly straws prepared in Examples 1 to 4 is ≥7.7 N, and the wet stiffness is ≥0.85 N. The dry stiffness and wet stiffness of the environmentally friendly straws prepared in Examples 1 to 4 all meet the requirements recorded in GB / T 44833. The material selection of the present invention is reasonable and the mechanical properties are excellent. Among them, the environmentally friendly straws prepared in Example 2 have the largest stiffness and are worthy of popularization and use.

[0029] Test Example 2: Water absorption of straws in liquid medium at 85°C Test content: The environmentally friendly straws prepared in Example 2 were set as the experimental group, and the food-grade adhesive in Example 2 was replaced with palm wax, which was recorded as the control group. The experimental group and the control group were placed in 85°C deionized water, 10% ethanol, and 4% acetic acid for 1 h, respectively, and the water absorption rates of the experimental group and the control group were calculated. Among them, water absorption rate = (mass after water absorption - mass before water absorption) / mass before water absorption × 100%, and the test results are recorded in Table 2.

[0030] Table 2

[0031] It can be seen from Table 2 that the environmentally friendly straws prepared in Example 2 have excellent waterproof and anti-penetration capabilities under the condition of 85° C., and the environmentally friendly straws have excellent high temperature resistance.

[0032] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An environmentally friendly straw, characterized by: The environmentally friendly straw is made of an outer layer of paper, a middle layer of paper and an inner layer of paper in a spiral winding manner, the outer layer of paper and the inner layer of paper are both food-grade bamboo pulp paper, the inner layer of paper is PLA coated paper, the middle layer of paper is respectively bonded to the outer layer of paper and the inner layer of paper by food-grade adhesive, and the surface of the outer layer of paper away from the middle layer of paper and the surface of the inner layer of paper away from the middle layer of paper are both coated with food-grade adhesive; The food-grade adhesive comprises the following components by mass: 30 parts of food-grade bamboo-based nanocellulose, 9-12 parts of high-acyl gellan gum, 9-12 parts of hydroxypropyl methylcellulose, 5-8 parts of mannoesters, 2-5 parts of food-grade tannic acid, 2-5 parts of linseed oil, 2-5 parts of tragacanth gum powder, 1-2 parts of celery polysaccharide, 1-2 parts of sorbitol, 0.5-1.0 parts of tea polyphenols and 20-25 parts of deionized water.

2. The environmentally friendly straw according to claim 1, characterized in that: The gram weight ratio of the outer layer paper, the middle layer paper and the inner layer paper is 1:1.2:1, and the thickness ratio of the outer layer paper, the middle layer paper and the inner layer paper is 1:1:

1.

3. The environmentally friendly straw according to claim 1, characterized in that: The average width of the food-grade bamboo-based nanocellulose is 5 to 20 nm, the specific surface area of ​​the food-grade bamboo-based nanocellulose is 150 to 300 m² / g, and the tensile strength of the food-grade bamboo-based nanocellulose is 100 to 200 MPa.

4. The environmentally friendly straw according to claim 1, characterized in that: The amide value of the high acyl gellan gum is 20-25, the viscosity of the hydroxypropyl methylcellulose is 4000-6500 mPa·s, and the mass ratio of the high acyl gellan gum to the hydroxypropyl methylcellulose is 1:

1.

5. A method for preparing an environmentally friendly straw as claimed in any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Material preparation: Cut the outer layer paper, the middle layer paper and the inner layer paper into paper strips with a width of 10 mm; S2, glue preparation: bamboo-based nanocellulose, high acyl gellan gum, hydroxypropyl methylcellulose and deionized water are mixed, and efficiently dispersed under ultrasonic stirring to obtain a dispersion liquid, and then mannosyl ester, food-grade tannic acid, linseed oil, tragacanth gum powder, herba schoenoprasum polysaccharides, sorbitol and tea polyphenols are sequentially added to the dispersion liquid, and stirred evenly to obtain a food-grade adhesive; S3, tube making: heating the food-grade adhesive to 40-50°C, first spirally winding the inner paper into a circular tube structure, then applying the food-grade adhesive on the inner and outer sides of the inner paper, then spirally winding the middle paper into a circular tube structure on the outer side of the inner paper, and applying the food-grade adhesive on the outer side of the middle paper, then spirally winding the outer paper into a circular tube structure on the outer side of the middle paper, and finally applying the food-grade adhesive on the outer side of the outer paper, drying, and obtaining a paper tube; S4. Cutting: Feed the paper tube into the straw beveling machine to cut out beveled cuts to obtain environmentally friendly straws.

6. The method for preparing an environmentally friendly straw according to claim 5, characterized in that: The spiral winding angles of the outer layer of paper, the middle layer of paper and the inner layer of paper are all 45°, the length of the environmentally friendly straw is 197 mm, and the caliber of the environmentally friendly straw is one of 8 mm, 10 mm and 12 mm.

7. The method for preparing an environmentally friendly straw according to claim 5, characterized in that: The thickness of the food-grade adhesive located on the inner side of the inner paper and on the outer side of the outer paper is 0.04-0.06 mm, and the thickness of the food-grade adhesive located on both the inner and outer sides of the middle paper is 0.1-0.3 mm.

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