An environment-friendly recyclable composite film of imitation tissue paper and a preparation method thereof

Abstract

The present application belongs to the technical field of film, especially a kind of environment-friendly recyclable composite film similar to cotton paper and a preparation method thereof.The material of the present application is formed by the outer film and the inner film being compounded by adhesive through a solvent-free compounding machine;the outer film is formed by A layer, B layer and C layer being connected in sequence and being stretched by three-layer co-extrusion blown film;the inner film is formed by D layer, E layer and F layer being connected in sequence and being stretched by three-layer co-extrusion blown film;and A layer is connected with D layer.The environment-friendly recyclable composite film similar to cotton paper has the advantages of appearance similar to paper, soft touch, high sealing strength and high tensile strength.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thin films, in particular to an environmentally friendly recyclable composite film with a paper-like texture and a preparation method thereof. BACKGROUND

[0002] The existing single composite material technology field is innovatively developed in the direction of single material recyclability, functionalization, alloying, modification and thinning, so as to promote the realization of environmentally friendly recyclability, carbon reduction and low-carbon green recyclable sustainable development of composite packaging.

[0003] However, the existing paper-like packaging in China must use paper-plastic and paper-sensing coating to achieve texture, and both of these two methods are difficult to recycle and have high stiffness, and organic gas emissions are generated during the production process, and the sealing strength and tensile strength are relatively low, which cannot meet the requirements of anti-deformation performance when used in customer's automatic high-speed packaging line and the requirement of heat resistance during heat sealing. SUMMARY

[0004] In order to solve the above technical problems, the present application provides an environmentally friendly recyclable composite film with a paper-like texture and a preparation method thereof, which has a soft touch, high sealing strength and high tensile strength.

[0005] In order to achieve one of the purposes of the present application, the following technical solutions are adopted:

[0006] An environmentally friendly recyclable composite film with a paper-like texture, which is composed of an outer film and an inner film compounded by a solvent-free compound machine using an adhesive; the outer film is made of A layer, B layer and C layer connected in sequence and stretched by three-layer co-extrusion film blowing, and the inner film is made of D layer, E layer and F layer connected in sequence and stretched by three-layer co-extrusion film blowing, and A layer is connected with D layer.

[0007] Preferably, A layer and C layer are each composed of 25-30 parts by mass of polyolefin plasticizer (POE), 69-74 parts by mass of inorganic masterbatch and 1 part by mass of processing aid; B layer is composed of 15 parts by mass of metallocene low-density polyethylene, 70-75 parts by mass of inorganic masterbatch, 9-14 parts by mass of high-pressure polyethylene and 1 part by mass of processing aid.

[0008] Preferably, the brand of polyolefin plasticizer is PL1881 produced by Dow Chemical Company, the brand of metallocene low-density polyethylene is 2012MC produced by Exxon Company, the brand of high-pressure polyethylene is 2420H produced by Yangzi Petrochemical Company, and the brand of processing aid is 100991-K produced by Anpia Color Company; the inorganic masterbatch is blended and processed by a double-screw granulator from metallocene low-density polyethylene and powder calcium carbonate in a mass ratio of 1:1, and the brand of powder calcium carbonate is Flim Link 520 produced by Yingge Ceramics Company.

[0009] Preferably, the D layer and the F layer are each composed of 40-50 parts by mass of polyolefin plastomer, 29-39 parts by mass of metallocene low-density polyethylene, 20 parts by mass of high-pressure polyethylene, and 1 part by mass of processing aid; the E layer is composed of 50 parts by mass of metallocene low-density polyethylene, 22 parts by mass of white masterbatch, 27 parts by mass of high-pressure polyethylene, and 1 part by mass of processing aid.

[0010] Preferably, the polyolefin plastomer is of the brand PL1881 produced by Dow Chemical Company, the metallocene low-density polyethylene is of the brand 2012MC produced by Exxon Company, the high-pressure polyethylene is of the brand 2420H produced by Yangzi Petrochemical Company, the white masterbatch is of the brand EM9016 produced by Huangshan Shangfu Company, and the white masterbatch is extruded by blending titanium white powder and polyethylene; the processing aid is of the brand 100991-K produced by Anpiai Company.

[0011] The polyolefin plastomer has a density of 0.904 g / cm 3 and a melt index of 1.0 g / 10 min. 190℃ / 2.16 kg; the metallocene low-density polyethylene has a density of 0.912 g / cm 3 and a melt index of 2.0 g / 10 min. 190℃ / 2.16 kg; the calcium carbonate has a density of 2.7-2.95 g / cm 3 ; the inorganic masterbatch after twin-screw blending has a density of 1.72-1.78 g / cm 3 and a melt index of 1.2-2.0 g / 10 min. 190℃ / 2.16 kg; the high-pressure polyethylene has a density of 0.925 g / cm 3 and a melt index of 2.0 g / 10 min. 190℃ / 2.16 kg; the processing aid has a density of 0.940 g / cm 3 and a melt index of 2.5 g / 10 min. 190℃ / 2.16 kg.

[0012] Preferably, the thickness ratio of the A layer, the B layer, and the C layer is (20-30):(40-60):(20-30); the thickness ratio of the D layer, the E layer, and the F layer is (20-30):(40-60):(20-30).

[0013] Preferably, the mass ratio of the main agent to the curing agent in the adhesive is 100:70; the main agent is of the brand LA7728 produced by Hanqiao Company, and the curing agent is of the brand LA6028 produced by Hanqiao Company.

[0014] The main agent has a viscosity of 1125±275 mpas and a density of 1.17 g / cm 3 ; the curing agent has a viscosity of 5000±2000 mpas and a density of 1.10 g / cm3 The viscosity of the two components after mixing at 40℃ is 1500mpas; the adhesive is transferred from the metering steel roll to the metering steel roll using a sleeve type silica gel roll, and the adhesive is applied using an outer film, with an adhesive amount of 1.4±0.3g / m 2 .

[0015] To achieve the second purpose of the present application, the present application provides a preparation method of an environmentally friendly recyclable composite film of imitation tissue paper, comprising the following steps:

[0016] S1, preparing an outer film: the materials of layers A, B and C are respectively put into the barrel of a film blowing machine for melt co-extrusion, and sequentially pass through extrusion melting, bubble drawing, automatic side thickening, bubble calming, primary traction, MDO stretching and setting, corona, secondary traction and winding, to form a bubble to obtain a three-layer co-extruded blown outer film;

[0017] S2, preparing an inner film: the materials of layers D, E and F are respectively put into the barrel of a film blowing machine for melt co-extrusion, and sequentially pass through extrusion melting, bubble drawing, automatic side thickening, bubble calming, primary traction, corona, secondary traction, winding, to form a bubble to obtain a three-layer co-extruded blown inner film;

[0018] S3, suspending the outer film and the inner film for 24 hours, and then using an adhesive to pass through a solvent-free compounding machine to obtain a composite film.

[0019] Preferably, in step S1, the melting section temperature of the film blowing machine is 40-80℃, the extrusion section temperature is 185-195℃, the die temperature is 190℃, the extrusion amount is 500-630kg / h; the bubble drawing blow-up ratio is 1:(1.5-2.8); the primary traction tension is 150N, the secondary traction tension is 120N, and the winding pressure is 100N-200N to ensure normal operation of the base film; the automatic side thickening rotation time is 35min-60min to ensure that the film points can be automatically adjusted stably and ensure the uniformity of the film thickness; the MDO stretching and setting stretching ratio is 3.8-5.0, and the eight-roller temperature setting is PH1 75℃, PH2 85℃, SD roller 90℃, FD roller temperature 94℃, setting roller AD1 95℃, AD2 95℃, cooling roller CD1 temperature 40℃, CD2 30℃, to ensure smooth operation of the film.

[0020] Preferably, in step S2, the temperature of the melt section of the film blowing machine is 40-80 DEG C, the temperature of the extrusion section is 185-195 DEG C, the temperature of the die head is 190 DEG C, the extrusion amount is 500-630 kg / h; the bubble blowing ratio of the bubble is 1: (1.2-2.5); the tension of the first traction is 120 N, the tension of the second traction is 80 N, and the pressure of the winding is 80 N-120 N, so as to ensure the normal operation of the base film; the rotation time of the automatic side thickness is 55 min-85 min, so as to ensure that the film points can be automatically adjusted stably, and the uniformity of the film thickness is ensured.

[0021] The composite film material compounded by the solvent-free compounding machine can be subjected to the corona machine, so that the surface energy of the composite film can reach 38 dynes or more, and the composite film material can be subjected to subsequent processing such as printing and gluing. The material can simulate recycling disposal, and the film material can be wound or cut into blocks, and directly subjected to a double-screw or single-screw granulator at a temperature of 190 DEG C, to present a uniform white master batch, the color of which is uniform, no smoke or peculiar smell is generated in the granulation process, and the recycled master batch can be used as a packaging express bag, an industrial packaging bag or the like.

[0022] The present application has the following beneficial effects compared with the prior art:

[0023] 1) The present application forms a kind of quasi-cotton paper environment-friendly green composite film material by special solvent-free adhesive compounding of outer film and inner film, and the whole process of the preparation process is green and environment-friendly, the product appearance is similar to paper, the touch is soft, the sealing strength is high, the tensile strength is high, etc., which can meet the requirements of anti-deformation ability and good heat resistance during heat sealing when used in customer end automatic high-speed packaging line;It changes the consumer's cognition of plastic packaging, fully embodies the soft, sanitary, silky and other characteristics of the packaged goods, makes up for the blank of using paper feeling packaging to realize the texture by using paper plastic and coating paper feeling coating in China, and greatly improves the problems of difficult recycling, high stiffness and organic gas emission of traditional packaging composite film in the production process.

[0024] 2) The quasi-cotton function composite film of the present application is composed of a multi-layer structure, uses high molecular polymer as a base material, adjusts its microstructure by special additives (POE), gives the film material excellent flexibility and good mechanical strength, so that the finally prepared composite film has the advantages of quasi-cotton, high tensile strength, excellent sealing performance, single material recycling, thinning and the like.

[0025] 3) In the present application, the outer film is filled with inorganic matter blending design, so that the composite film surface has special softness and elasticity, simulates the touch of natural fabric, enhances the affinity and comfort of the product; the composite film not only has excellent air permeability, is suitable for occasions such as medical dressings, smart wearable devices and the like which need to balance the humidity of the internal and external environment; and the single material selected can be recycled, combined with an environmentally friendly preparation process, to ensure that the composite film can be recycled and degraded again after recycling, reducing environmental pollution and being environmentally friendly and recyclable.

[0026] 4) The advantages of the composite film of the present application compared with the prior art are:

[0027] ①, can significantly improve the user experience, the design of the cotton-like soft touch makes the composite film material more skin-friendly and comfortable in terms of touch, especially in products that directly contact the skin, significantly improving user satisfaction;

[0028] ②, the comprehensive performance is better, not only maintains the air permeability, excellent mechanical physical properties and the like of traditional film materials, but also realizes the new functions of antibiosis and recyclability through the structure of the core, which can meet the needs of more customers and the requirements of the recyclable trend of the market;

[0029] ③, has a wider application prospect, with its unique performance combination, the composite film has a wide application prospect in packaging, medical treatment, environmental protection, electronic protection and the like. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below in combination with embodiments, and all other embodiments obtained by those skilled in the art without creative labor on the basis of the embodiments in the present application belong to the scope of protection of the present application.

[0031] Example 1

[0032] A kind of environmental protection recyclable composite film of cotton-like paper, the material ratio component is as shown in the following table 1:

[0033] Table 1

[0034]

[0035] A kind of environmental protection recyclable composite film of cotton-like paper and its preparation method, comprising the following steps:

[0036] S1, preparing outer film: the materials of A layer, B layer and C layer are respectively put into the cylinder of the film blowing machine for melt co-extrusion, successively through extrusion melting, bubble drawing, automatic side thick, bubble, first traction, MDO stretching and setting, corona, secondary traction and winding, forming film bubble to obtain three-layer co-extrusion blown outer film;

[0037] The melt section temperature of the film blowing machine is 50 DEG C, the extrusion section temperature is 190 DEG C, the die temperature is 190 DEG C, and the extrusion amount is 530 kg / h; the bubble drawing ratio is 1:2.2; the primary traction tension is set to 150 N, the secondary traction tension is 120 N, and the winding pressure is 140 N, so as to ensure the normal operation of the base film; the rotation time of the automatic side thickness is 80 min, so as to ensure that each point of the base film can be automatically adjusted stably and the uniformity of the thickness of the base film is ensured; the MDO stretching ratio is 4.065, and the eight-roller temperature parameters are set to PH1 70 DEG C, PH2 85 DEG C, SD roller 90 DEG C, FD roller temperature 95 DEG C, setting roller AD1 92 DEG C, setting roller AD2 94 DEG C, cooling roller CD1 50 DEG C, and CD2 30 DEG C, so as to ensure the flat setting and the stability of the linear speed of the base film.

[0038] S2, preparing an inner film: the materials of the D layer, the E layer and the F layer are respectively put into the barrel of the film blowing machine for melt co-extrusion, and sequentially pass through extrusion melting, bubble drawing, automatic side thickness, bubble calming, primary traction, corona discharge, secondary traction and winding, so as to form a film bubble and obtain a three-layer co-extrusion blown inner film;

[0039] The melt section temperature of the film blowing machine is 50 DEG C, the extrusion section temperature is 180 DEG C, the die temperature is 180 DEG C, and the extrusion amount is 520 kg / h; the bubble drawing ratio is 1:1.8; the primary traction tension is set to 150 N, the secondary traction tension is 70 N, and the winding pressure is 100 N, so as to ensure the normal operation of the base film; the rotation time of the automatic side thickness is 35 min, so as to ensure that each point of the base film can be automatically adjusted stably and the uniformity of the thickness of the base film is ensured.

[0040] S3, suspending the outer film and the inner film for 24 hours, and then using an adhesive to pass through a solvent-free laminating machine to prepare a composite film 1.

[0041] Example 2

[0042] A kind of pseudo-mulberry paper environmental protection recyclable composite film, the proportioning ingredient of its material is shown in the following table 2:

[0043] Table 2

[0044]

[0045] A kind of pseudo-mulberry paper environmental protection recyclable composite film and its preparation method, including the following steps:

[0046] S1, preparing an outer film: the materials of the A layer, the B layer and the C layer are respectively put into the barrel of the film blowing machine for melt co-extrusion, and sequentially pass through extrusion melting, bubble drawing, automatic side thickness, bubble calming, primary traction, MDO stretching setting, corona discharge, secondary traction and winding, so as to form a film bubble and obtain a three-layer co-extrusion blown outer film;

[0047] The melt section temperature of the film blowing machine is 50 DEG C, the extrusion section temperature is 190 DEG C, the die temperature is 190 DEG C, and the extrusion amount is 510 kg / h; the bubble drawing ratio is 1:2.2; the primary traction tension is set to 120 N, the secondary traction tension is 70 N, and the winding pressure is 140 N, so as to ensure the normal operation of the base film; the automatic side thickness rotation time is 80 min, so as to ensure that each point of the base film can be stably and automatically adjusted, and the uniformity of the base film thickness is ensured; the MDO stretching ratio is 4.212, and the eight-roller temperature parameters are set to PH1 70 DEG C, PH2 85 DEG C, SD roller 90 DEG C, FD roller temperature 90 DEG C, setting roller AD1 92 DEG C, setting roller AD2 92 DEG C, cooling roller CD1 30 DEG C, and CD2 20 DEG C, so as to ensure the flat setting and the stability of the linear speed of the base film.

[0048] S2, preparing the inner film: the materials of the D layer, the E layer and the F layer are respectively put into the barrel of the film blowing machine for melt co-extrusion, and sequentially pass through extrusion melting, bubble drawing, automatic side thickness, bubble stopping, primary traction, corona discharge, secondary traction and winding, so as to form a film bubble and obtain a three-layer co-extruded inner film by blowing;

[0049] The melt section temperature of the film blowing machine is 55 DEG C, the extrusion section temperature is 182 DEG C, the die temperature is 182 DEG C, and the extrusion amount is 520 kg / h; the bubble drawing ratio is 1:1.8; the primary traction tension is set to 130 N, the secondary traction tension is 70 N, and the winding pressure is 90 N, so as to ensure the normal operation of the base film; the automatic side thickness rotation time is 55 min, so as to ensure that each point of the base film can be stably and automatically adjusted, and the uniformity of the base film thickness is ensured.

[0050] S3, the outer film and the inner film are both suspended for 24 hours, and then are compounded by using the adhesive through the solvent-free compound machine, so as to obtain the compound film 2.

[0051] The compound films 1-2 obtained by the above examples 1-2 and the ordinary PE white film / PE white film are tested for performance, and the comparison results are shown in the following table 3:

[0052] Table 3

[0053]

[0054] The tensile strength: measures the film toughness, tensile strength, compound film breaking resistance, etc., which meets the requirements;

[0055] The 10% tensile force: measures the deformation resistance of the film in the processing process;

[0056] The elongation at break: represents the film toughness, deformation resistance, etc.

[0057] The friction coefficient: the surface friction coefficient value, which is close to the parameter of tissue paper, 0.40-0.6;

[0058] Interlayer peeling strength: composite film interlayer adhesion strength, measures material strength, easy to tear, etc.

[0059] Right angle tear: measures the easy-to-tear performance of the packaging material.

[0060] Flexural modulus: measures the softness of the composite film;

[0061] Puncture strength: measures the toughness of the film and the ability to resist product puncture;

[0062] Glossiness: measures the surface softness of the tissue paper, the higher the value, the worse the texture;

[0063] Whiteness: measures the hiding power of the film material, the higher the value, the closer to the tissue paper.

[0064] As can be seen from Table 3 above, the elastic modulus, appearance tissue paper hand feeling, whiteness, sealing performance, etc. of the product of the present application can be significantly better than that of the PE white film / PE white film material product, therefore the composite film of the present application has good toughness and tensile strength, can meet the requirements of the packaging material to withstand various external forces during use, has good ductility, thereby improving its safety and stability during use; the friction coefficient range of 0.4-0.6 is close to the parameters of tissue paper, which helps to give the composite film material similar touch of tissue paper, improving user experience; lower flexural modulus indicates that the composite film is softer and more easily adapts to packaging requirements of different shapes and sizes, which is of great significance to improve the aesthetics and user experience of packaging, and lower glossiness and higher whiteness make the film look more natural and soft, which helps to improve the overall visual effect of the packaging, fully meeting the development prospects of the industry.

[0065] In step S3 of Examples 1-2, the glue mixer temperature is 42±2℃, the glue delivery pipe temperature is 42℃, the fixed roller and metering roller temperature is set to 42℃, the coating roller is stably set to 55℃, the transfer roller and pressure roller pressure is set to 0.4Mpa, the fixed roller and metering roller gap is set to 80±5um; the metering roller and transfer roller speed ratio is 20%, to ensure uniform spreading and stable glue coating amount; the unwinding tension is set to 10±2 kg, the second unwinding tension is 5±2 kg, the drying channel tension is 6±2 kg, the winding tension is 10±2 kg, the winding tension decrement curve is 75%, the winding pressure roller pressure is 0.4±0.05Mpa; the no-solvent compounding machine is started at a speed of 280±20 meters / min, and after winding, it is placed horizontally, and the curing condition is 45℃ oven curing for 24H; after curing, printing, glue coating and other processing can be carried out.

[0066] The present application belongs to the technical field of single composite composite packaging, which has a new breakthrough in eliminating plastic feeling, recycling, thinning, low carbon, light shielding rate (whiteness) and other functions. Compared with the traditional polyethylene composite film material, it has obvious advantages, the consumer experience is very novel, promotes the desire and product performance, and can be widely used in life paper packaging, clothing, gifts, labels and other packaging. It has obvious advantages in cost control, recycling, recycling disposal and other aspects.

Claims

1. An eco-friendly recyclable composite film resembling tissue paper, characterized by, The composite film is prepared by compounding the outer film and the inner film by using the adhesive through the solvent-free compounder; the outer film is prepared by sequentially connecting the A layer, the B layer and the C layer through three-layer co-extrusion blown film stretching, the inner film is prepared by sequentially connecting the D layer, the E layer and the F layer through three-layer co-extrusion blown film stretching, and the A layer is connected with the D layer; The A layer and the C layer are both composed of 25-30 parts by mass of polyolefin plastomer, 69-74 parts by mass of inorganic master batch and 1 part by mass of processing aid; the B layer is composed of 15 parts by mass of metallocene low-density polyethylene, 70-75 parts by mass of inorganic master batch, 9-14 parts by mass of high-pressure polyethylene and 1 part by mass of processing aid; The D layer and the F layer are both composed of 40-50 parts by mass of polyolefin plastomer, 29-39 parts by mass of metallocene low-density polyethylene, 20 parts by mass of high-pressure polyethylene and 1 part by mass of processing aid; the E layer is composed of 50 parts by mass of metallocene low-density polyethylene, 22 parts by mass of white master batch, 27 parts by mass of high-pressure polyethylene and 1 part by mass of processing aid; The polyolefin plastomer is PL1881 produced by Dow Chemical Company, the metallocene low-density polyethylene is 2012MC produced by Exxon Company, the high-pressure polyethylene is 2420H produced by Yangzi Petrochemical Company, and the processing aid is 100991-K produced by Anpia Color Company; the inorganic master batch is prepared by blending and processing metallocene low-density polyethylene and powder calcium carbonate in a mass ratio of 1:1 through a double-screw granulator, and the powder calcium carbonate is Flim Link 520 produced by Yingge Ceramics Company; The white master batch is EM9016 produced by Huangshan Shangfu Company.

2. The environment-friendly recyclable composite film according to claim 1, wherein, The thickness ratio of the A layer, the B layer and the C layer is (20-30):(40-60):(20-30), and the thickness ratio of the D layer, the E layer and the F layer is (20-30):(40-60):(20-30).

3. The environment-friendly recyclable composite film according to claim 1, wherein the cellulose fiber is selected from the group consisting of wood pulp, cotton, hemp, linen, jute, ramie, sisal, and a mixture thereof. The mass ratio of the main agent and the curing agent in the adhesive is 100:70, the main agent is LA7728 produced by Hanqiao Company, and the curing agent is LA6028 produced by Hanqiao Company.

4. A method of preparing the eco-friendly and recyclable composite film of claim any one of claims 1-3, characterized in that, The method comprises the following steps: S1, preparing the outer film: the materials of the A layer, the B layer and the C layer are respectively put into the cylinder of the film blowing machine for melt co-extrusion, sequentially passing through extrusion melting, bubble drawing, automatic side thickening, bubble calming, primary traction, MDO stretching and setting, corona discharge, secondary traction and winding, forming a film bubble to obtain a three-layer co-extrusion blown outer film; S2, preparing the inner film: the materials of the D layer, the E layer and the F layer are respectively put into the cylinder of the film blowing machine for melt co-extrusion, sequentially passing through extrusion melting, bubble drawing, automatic side thickening, bubble calming, primary traction, corona discharge, secondary traction, winding, forming a film bubble to obtain a three-layer co-extrusion blown inner film; S3, suspending the outer film and the inner film for 24 hours, and then compounding the outer film and the inner film by using the adhesive through the solvent-free compounder to prepare a composite film.

5. The method of claim 4, wherein the method further comprises the step of: 5.

1. drying the mixture of step 4.1 to obtain a dried mixture; and 5.

2. mixing the dried mixture of step 5.1 with the binder to obtain the mixture of step 4.

2. In step S1, the melt section temperature of the film blowing machine is 40-80℃, the extrusion section temperature is 185-195℃, the die temperature is 190℃, the extrusion amount is 500-630kg / h; the bubble drawing ratio is 1: (1.5-2.8); the first traction tension is 150N, the second traction tension is 120N, the winding pressure is 100N-200N; the automatic side thickness rotation time is 35min-60min; the MDO stretching setting stretching ratio is 3.8-5.

0. ​ 6. The method of claim 4, wherein the method further comprises the step of: 6-1) drying the mixture of step 5-1) to obtain the recycled composite film. In step S2, the melt section temperature of the film blowing machine is 40-80℃, the extrusion section temperature is 185-195℃, the die temperature is 190℃, the extrusion amount is 500-630kg / h; the bubble drawing ratio is 1: (1.2-2.5); the first traction tension is 120N, the second traction tension is 80N, the winding pressure is 80N-120N; the automatic side thickness rotation time is 55min-85min.

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