Recyclable toothpaste sheet and preparation process thereof

Abstract

The invention relates to the technical field of recyclable packaging materials, and discloses a recyclable toothpaste sheet and a preparation process thereof, the preparation process comprises the following steps: synthesizing an organic-inorganic hybrid modified monomer, the organic-inorganic hybrid modified monomer is an organic-inorganic hybrid modified monomer M1 or an organic-inorganic hybrid modified monomer M2; a benzene ring contained in an organic-inorganic hybrid modified monomer and a benzene ring structure rich in a molecular main chain in the polyether-ether-ketone resin are subjected to a pi-pi accumulation effect, and the polyether-ether-ketone resin is modified by utilizing the organic-inorganic hybrid modified monomer, so that the modified polyether-ether-ketone is prepared. Modified polyether-ether-ketone is introduced into a single PE material, a five-layer co-extrusion blow molding film forming process is adopted, the recyclable toothpaste sheet with excellent mechanical properties is prepared, and the composite sheet can be recycled.

Description

Technical Field

[0001] The present invention relates to the technical field of recyclable packaging materials, and particularly to a recyclable toothpaste sheet material and a preparation process thereof. Background Art

[0002] At present, the common toothpaste sheet material on the market has a primary composite molding structure of PE / extruded EAA / Al / extruded EAA / PE. Because the composition materials not only include plastic layers, but also materials such as aluminum foil and coatings that are difficult to separate, the sorting and classification processes of this structure of toothpaste sheet material after use are cumbersome and difficult, and the recycling rate of the materials is low. The single-material all-plastic composite sheet does not contain aluminum foil and does not need to be classified during recycling and can be recycled, but its mechanical properties such as stiffness, hardness, and strength will be significantly reduced, bringing potential adverse factors to the normal use of the material.

[0003] Polyetheretherketone (PEEK) is a semi-crystalline thermoplastic special plastic with very high mechanical strength and is recognized as one of the materials at the tip of the polymer pyramid; in addition, cage-like polyhedral oligomeric silsesquioxane is an organic-inorganic hybrid material including an inorganic core and an organic outer layer, which performs excellently in enhancing material toughness, hardness, scratch resistance, etc. Summary of the Invention

[0004] The present invention independently developed a new type of modified polyetheretherketone, and used the modified polyetheretherketone to improve the mechanical properties of the single PE material, and prepared a composite sheet with excellent tensile strength, bending strength and impact strength. This composite sheet can be recycled and can be used to manufacture toothpaste packaging materials.

[0005] A preparation process of a recyclable toothpaste sheet material includes the following steps:

[0006] Step 1: Synthesize an organic-inorganic hybrid modified monomer, and the organic-inorganic hybrid modified monomer is organic-inorganic hybrid modified monomer M1 or organic-inorganic hybrid modified monomer M2;

[0007] Step 2: Through the π-π stacking effect between the benzene ring contained in the organic-inorganic hybrid modified monomer and the benzene ring structure rich in the molecular main chain of the polyetheretherketone resin, use the organic-inorganic hybrid modified monomer to modify the polyetheretherketone resin to prepare a modified polyetheretherketone;

[0008] Step 3: Introduce the modified polyetheretherketone into the single PE material and adopt a five-layer co-extrusion blow molding process to prepare a recyclable toothpaste sheet material.

[0009] Preferably, the preparation method of the organic-inorganic hybrid modified monomer M1 is as follows: It is prepared by the addition reaction of the alkenyl functional groups of 1 molar equivalent of octavinyl polyhedral oligomeric silsesquioxane with the Si-H bonds of (8.01 to 8.05) molar equivalents of dimethylphenylsilane.

[0010] Preferably, the preparation method of the organic-inorganic hybrid modified monomer M2 is as follows: It is prepared by the addition reaction of the alkenyl functional groups of 1 molar equivalent of octavinyl polyhedral oligomeric silsesquioxane with the Si-H bonds of (8.01 to 8.05) molar equivalents of diphenylmethylsilane.

[0011] Preferably, the preparation method of the recyclable toothpaste sheet is as follows:

[0012] Step S4-1: Set the recyclable toothpaste sheet as a five-layer asymmetric membrane structure, and the formula and dosage of each membrane layer are as follows:

[0013] The first layer: The formula is 90-99 wt% low-density polyethylene resin, 1-10 wt% composite auxiliary agent, and the dosage is 5-20 parts by weight;

[0014] The second layer: The formula is 90-99 wt% high-density polyethylene resin and 1-10 wt% modified polyether ether ketone, and the dosage is 20-40 parts by weight;

[0015] The third layer: The formula is 90-99 wt% low-density polyethylene resin and 1-10 wt% ethylene-vinyl alcohol copolymer resin, and the dosage is 10-30 parts by weight;

[0016] The fourth layer: The formula is 90-99 wt% high-density polyethylene resin and 1-10 wt% modified polyether ether ketone, and the dosage is 20-40 parts by weight;

[0017] The fifth layer: The formula is 100 wt% low-density polyethylene resin, and the dosage is 5-20 parts by weight;

[0018] Step S4-2: Put the raw materials in Step S4-1 into the hoppers of five screw extruders of a five-layer coextrusion film blowing machine respectively. After stirring and mixing, the molten resin converges at the head through a diverter, and is extruded, blown, cooled and wound through a die head to obtain a recyclable toothpaste sheet.

[0019] Preferably, the mass ratio of the organic-inorganic hybrid modified monomer to the polyether ether ketone resin in the modified polyether ether ketone is 1:(10-30).

[0020] Preferably, the composite auxiliary agent is an antioxidant and an ultraviolet absorber;

[0021] Preferably, the antioxidant is antioxidant 168 or antioxidant 1010;

[0022] Preferably, the ultraviolet light absorber is ultraviolet light absorber UV-329 or ultraviolet light absorber UV-234.

[0023] The thickness of a recyclable toothpaste sheet prepared according to the above process is 250-350 μm.

[0024] Preferably, the recyclable toothpaste sheet has a tensile strength of 50-60 MPa, a flexural strength of 55-65 MPa, and an impact strength of 8.0-9.5 kJ / m 2 .

[0025] Beneficial effects:

[0026] In the present invention, a cage-type polyhedral oligomeric silsesquioxane with excellent mechanical properties is used as a raw material to design and synthesize an organic-inorganic hybrid modified monomer. Then, based on the π-π stacking effect of the benzene ring structure, the organic-inorganic hybrid modified monomer is used to modify a polyether ether ketone resin to prepare a modified polyether ether ketone. The modified polyether ether ketone is introduced into a single-material PE coextrusion film, and a five-layer coextrusion blow molding process is used to prepare a recyclable toothpaste sheet;

[0027] It is found through experiments that: compared with the base sheet without the addition of the modified polyether ether ketone in the formula, the recyclable toothpaste sheet prepared in the present invention can significantly improve the tensile strength, flexural strength and impact strength, showing excellent mechanical properties;

[0028] It is also found that the recyclable toothpaste sheet prepared in the present invention has excellent comprehensive properties, meets the hygiene standards and has no safety hazards, and can be used in toothpaste packaging. Description of the drawings

[0029] Figure 1 is the chemical structural formula of the organic-inorganic hybrid modified monomer M1;

[0030] Figure 2 is the chemical structural formula of the organic-inorganic hybrid modified monomer M2;

[0031] Figure 3 are the performance test results of the recyclable toothpaste sheet. Detailed implementation manners

[0032] Experimental example 1:

[0033] Prepare the organic-inorganic hybrid modified monomer M1. The preparation method is: an addition reaction occurs between the alkenyl functional groups of 1 molar equivalent of octavinyl polyhedral oligomeric silsesquioxane and the Si-H bonds of 8.02 molar equivalents of dimethylphenylsilane to generate the organic-inorganic hybrid modified monomer M1. Its chemical structural formula is as Figure 1As shown below, the specific preparation steps are as follows: Add 3.2 g of octavinyl polyhedral oligomeric silsesquioxane and 30 mL of anhydrous tetrahydrofuran to a four-necked flask under nitrogen protection, stir at room temperature until completely dissolved, then dropwise add 50 mL of an anhydrous tetrahydrofuran solution containing 5.5 g of dimethylphenylsilane to the four-necked flask, add 5 drops of Karstedt catalyst dropwise under stirring, heat up to 75 °C and stir under reflux for 12 h, cool to room temperature, remove the solvent by rotary evaporation, and dry under vacuum to obtain the organic-inorganic hybrid modified monomer M1;

[0034] The 1H NMR characterization of the organic-inorganic hybrid modified monomer M1 is as follows: 1 H NMR(CDCl3, 400 MHz) δ: 0.25(s, 48H), 0.65 - 0.69(t, 16H), 1.14 - 1.18(t, 16H), 7.28 - 7.65(m, 40H).

[0035] Experimental Example 2:

[0036] Prepare the organic-inorganic hybrid modified monomer M2. The preparation method is as follows: Through the addition reaction of the alkenyl functional groups of 1 molar equivalent of octavinyl polyhedral oligomeric silsesquioxane and the Si-H bonds of 8.02 molar equivalents of diphenylmethylsilane, the organic-inorganic hybrid modified monomer M2 is generated. Its chemical structural formula is as Figure 2 shown. The only difference in its specific preparation steps from those of the organic-inorganic hybrid modified monomer M1 is that 8.0 g of diphenylmethylsilane is used to replace 5.5 g of dimethylphenylsilane;

[0037] The 1H NMR characterization of the organic-inorganic hybrid modified monomer M2 is as follows: 1 H NMR(CDCl3, 400 MHz) δ: 0.74(s, 24H), 1.19 - 1.24(t, 16H), 1.75 - 1.79(t, 16H), 7.28 - 7.47(m, 80H).

[0038] Example 1:

[0039] Prepare the modified polyetheretherketone PEEK-Ⅰ: Through the π-π stacking interaction between the benzene rings contained in the organic-inorganic hybrid modified monomer M1 and the benzene ring structures rich in the molecular main chain of the polyetheretherketone resin, use the organic-inorganic hybrid modified monomer M1 to modify the polyetheretherketone resin. The specific preparation steps are as follows: Add 10 g of polyetheretherketone resin and 0.5 g of the organic-inorganic hybrid modified monomer M1 to a twin-screw extruder, and through the twin-screw extruder, blend, melt, extrude, and pelletize to obtain the modified polyetheretherketone PEEK-Ⅰ;

[0040] Among them, the process parameters of the twin-screw extruder are set as follows: the temperatures of zones 1-3 are 290 °C, 320 °C, and 340 °C respectively, and the rotation speed is 60 r / min;

[0041] The polyetheretherketone resin was purchased from Dongguan Bairong Plastic Raw Materials Co., Ltd., and its grade is 450G.

[0042] Example 2:

[0043] Prepare modified polyetheretherketone PEEK-II: Through the π-π stacking effect between the benzene rings contained in the organic-inorganic hybrid modifier monomer M2 and the benzene ring structures rich in the molecular main chain of the polyetheretherketone resin, the polyetheretherketone resin was modified with the organic-inorganic hybrid modifier monomer M2 to prepare the modified polyetheretherketone PEEK-II. The specific preparation steps are only different from those of the modified polyetheretherketone PEEK-I in that: the organic-inorganic hybrid modifier monomer M2 is used to replace the organic-inorganic hybrid modifier monomer M1.

[0044] Example 3:

[0045] Prepare recyclable toothpaste sheet I, including the following steps:

[0046] Step 1: Set the recyclable toothpaste sheet I as a five-layer asymmetric film structure, and the formula and dosage of each film layer are as follows:

[0047] The first layer: The formula is 96 wt% low-density polyethylene resin, 2 wt% antioxidant 1010, and 2 wt% ultraviolet absorber UV-329, and the dosage is 10 parts by weight;

[0048] The second layer: The formula is 95 wt% high-density polyethylene resin and 5 wt% modified polyetheretherketone PEEK-I, and the dosage is 30 parts by weight;

[0049] The third layer: The formula is 93 wt% low-density polyethylene resin and 7 wt% ethylene-vinyl alcohol copolymer resin, and the dosage is 20 parts by weight;

[0050] The fourth layer: The formula is 95 wt% high-density polyethylene resin and 5 wt% modified polyetheretherketone PEEK-I, and the dosage is 30 parts by weight;

[0051] The fifth layer: The formula is 100 wt% low-density polyethylene resin, and the dosage is 10 parts by weight;

[0052] Step 2: Put the raw materials in Step 1 into the hoppers of five screw extruders of a five-layer coextrusion blown film unit respectively. After stirring and mixing, the molten resin converges at the head through a diverter, and is extruded, blown, cooled, and wound through a die head to obtain a recyclable toothpaste sheet I with a thickness of 300 μm;

[0053] Among them, the process parameters of the screw extruders corresponding to the first layer and the fifth layer are both set as follows: the temperatures of zones 1 - 3 are 120°C, 150°C, and 170°C respectively, the runner temperature is 165°C, and the rotation speed is 30 r / min;

[0054] The process parameters of the screw extruders corresponding to the second layer and the fourth layer are both set as follows: the temperatures of zones 1 - 3 are 200°C, 240°C, and 290°C respectively, the runner temperature is 280°C, and the rotation speed is 60 r / min;

[0055] The process parameters of the screw extruder corresponding to the third layer are set as follows: the temperatures of zones 1 - 3 are 150°C, 170°C, and 190°C respectively, the runner temperature is 185°C, and the rotation speed is 40 r / min;

[0056] The low - density polyethylene resin is purchased from Jiangsu Rantai Plasticizing Co., Ltd., and its grade is LD 150DW; the high - density polyethylene resin is purchased from Dongguan Longhuang Plastic Raw Materials Co., Ltd., and its grade is FB5600; the ethylene - vinyl alcohol copolymer resin is purchased from Dongguan Kaixili Plastic Raw Materials Co., Ltd., and its grade is E105B.

[0057] Example 4:

[0058] Only use the modified polyether ether ketone PEEK - Ⅱ to replace the modified polyether ether ketone PEEK - Ⅰ in the recyclable toothpaste sheet Ⅰ, and the rest are the same as those of the recyclable toothpaste sheet Ⅰ to prepare the recyclable toothpaste sheet Ⅱ.

[0059] Comparative example:

[0060] Prepare the base sheet: Refer to the preparation experiment of the recyclable toothpaste sheet Ⅰ, and the difference is only that: do not use the modified polyether ether ketone PEEK - Ⅰ to prepare the base sheet.

[0061] Performance test:

[0062] I. Mechanical property test:

[0063] (1) Use an Instron 5565 universal tensile testing machine to test the tensile properties of the sample according to GB / T 1040 - 2006 "Determination of Tensile Properties of Plastics", and record the tensile strength of the sample;

[0064] (2) Use an Instron 5565 universal tensile testing machine to test the bending properties of the sample according to GB / T 9341 - 2008 "Determination of Bending Properties of Plastics", and record the bending strength of the sample;

[0065] (3) The impact performance of the samples was tested using a ZBC-4B liquid crystal plastic pendulum impact testing machine in accordance with GB / T 1843-2008 "Determination of Izod impact strength of plastics", and the impact strength of the samples was recorded;

[0066] II. Barrier performance test:

[0067] (1) The oxygen barrier performance of the samples was tested using a Y110 oxygen permeation tester in accordance with GB / T 1038-2000, and the oxygen permeation amount of the samples was recorded;

[0068] (2) The water barrier performance of the samples was tested using a TC-03 water vapor permeation tester in accordance with GB / T 1037-2021, and the water vapor permeation amount of the samples was recorded;

[0069] III. Hygienic performance test:

[0070] The hygienic performance test method of the samples refers to GB / T 5009.60-2003 "Analysis method for hygienic standards of polyethylene, polystyrene and polypropylene molded products for food packaging", and the physical and chemical indexes of the experimental results are based on GB / T 5009.58-2003 "Analysis method for hygienic standards of polyethylene resin for food packaging";

[0071] The above experimental results are shown in Table 1-2 below.

[0072] Table 1 Experimental results of the performance of recyclable toothpaste sheets - I

[0073]

[0074] Table 2 Experimental results of the performance of recyclable toothpaste sheets - II

[0075]

[0076] Based on the experimental data in Table 1, Figure 3 , the following conclusions can be drawn through comprehensive analysis of the above experimental results:

[0077] Conclusion 1: Compared with the base sheet without adding modified polyetheretherketone in the formula, the recyclable toothpaste sheet prepared by the present invention can significantly improve the tensile strength, flexural strength and impact strength, showing excellent mechanical properties;

[0078] Conclusion 2: The recyclable toothpaste sheet prepared by the present invention has excellent comprehensive performance, meets the hygienic standards, has no safety hazards, and can be used in toothpaste packaging.

Claims

1. A preparation process of recyclable toothpaste sheet material, characterized in that, It includes the following steps: Step 1: Synthesize an organic-inorganic hybrid modified monomer, which is organic-inorganic hybrid modified monomer M1 or organic-inorganic hybrid modified monomer M2; The chemical structural formula of the organic-inorganic hybrid modified monomer M1 is: The chemical structural formula of the organic-inorganic hybrid modified monomer M2 is: Step 2: Through the π-π stacking effect between the benzene rings contained in the organic-inorganic hybrid modified monomer and the benzene ring structures rich in the molecular main chain of the polyether ether ketone resin, modify the polyether ether ketone resin with the organic-inorganic hybrid modified monomer to prepare a modified polyether ether ketone; Step 3: Introduce the modified polyether ether ketone into a single PE material and use a five-layer coextrusion blow molding process to prepare a recyclable toothpaste sheet.

2. The preparation process of a recyclable toothpaste sheet according to claim 1, characterized in that, The preparation method of the organic-inorganic hybrid modified monomer M1 is: Prepared by the addition reaction of the alkenyl functional groups of 1 molar equivalent of octavinyl polyhedral oligomeric silsesquioxane with the Si-H bonds of (8.01 - 8.05) molar equivalents of dimethylphenylsilane.

3. The preparation process of a recyclable toothpaste sheet according to claim 1, characterized in that, The preparation method of the organic-inorganic hybrid modified monomer M2 is: Prepared by the addition reaction of the alkenyl functional groups of 1 molar equivalent of octavinyl polyhedral oligomeric silsesquioxane with the Si-H bonds of (8.01 - 8.05) molar equivalents of diphenylmethylsilane.

4. The preparation process of a recyclable toothpaste sheet according to claim 1, characterized in that, The preparation method of the recyclable toothpaste sheet is: Step S4-1: Set the recyclable toothpaste sheet as a five-layer asymmetric film structure, and the formula and dosage of each film layer are as follows: The first layer: The formula is 90 - 99wt% low-density polyethylene resin, 1 - 10wt% composite additive, and the dosage is 5 - 20 parts by weight; The second layer: The formula is 90 - 99wt% high-density polyethylene resin and 1 - 10wt% modified polyether ether ketone, and the dosage is 20 - 40 parts by weight; The third layer: The formula is 90 - 99wt% low-density polyethylene resin and 1 - 10wt% ethylene-vinyl alcohol copolymer resin, and the dosage is 10 - 30 parts by weight; The fourth layer: The formula is 90 - 99wt% high-density polyethylene resin and 1 - 10wt% modified polyether ether ketone, and the dosage is 20 - 40 parts by weight; The fifth layer: The formula is 100wt% low-density polyethylene resin, and the dosage is 5 - 20 parts by weight; Step S4-2: Put the raw materials in Step S4-1 into the hoppers of five screw extruders of a five-layer coextrusion film blowing machine respectively. After stirring and mixing, the molten resin converges at the head through a diverter, and is extruded, blown, cooled, and wound through a die head to obtain a recyclable toothpaste sheet.

5. The preparation process of a recyclable toothpaste sheet according to claim 1, characterized in that, The mass ratio of the organic-inorganic hybrid modified monomer and the polyether ether ketone resin in the modified polyether ether ketone is 1:(10 - 30).

6. The preparation process of a recyclable toothpaste sheet according to claim 4, characterized in that, The composite additive is an antioxidant and an ultraviolet absorber; The antioxidant is antioxidant 168 or antioxidant 1010; The ultraviolet absorber is ultraviolet absorber UV-329 or ultraviolet absorber UV-234.

7. A recyclable toothpaste sheet prepared by the process according to any one of claims 1-6, characterized in that, The thickness of the recyclable toothpaste sheet is 250 - 350μm.

8. A recyclable toothpaste sheet according to claim 7, characterized in that, The tensile strength of the recyclable toothpaste sheet is 50-60 MPa, the flexural strength is 55-65 MPa, and the impact strength is 8.0-9.5 kJ / m 2 .

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