Biodegradable breathable film capable of absorbing peculiar smell through far infrared rays and preparation method of biodegradable breathable film

Abstract

The invention relates to the technical field of packaging films, provides a biodegradable breathable film capable of absorbing peculiar smell through far infrared rays and a preparation method of the biodegradable breathable film, and solves the problems that in the prior art, the technology is complex, the sanitary condition is poor, and preparation materials cannot be completely degraded. The moisture transmission coefficient of the biodegradable breathable film with the far infrared function and the peculiar smell absorbing function ranges from 1000 g / m < 2 >. 24 h to 3000 g / m < 2 >. 24 h, the biodegradable breathable film is of a double-layer structure and comprises an inner layer and an outer layer, the inner layer is a hydrophilic biodegradable modified film, the outer layer is a high-adsorption far infrared biodegradable modified film, and the thickness ratio of the inner layer to the outer layer is 1: (1-3); the biodegradable breathable film with the far infrared function and capable of absorbing the peculiar smell is prepared from the following raw materials: hydrophilic biodegradable modified granules and a high-adsorption far infrared biodegradable modified material.

Description

Technical Field

[0001] The invention relates to the technical field of packaging films, in particular to a far-infrared odor-absorbing biodegradable breathable film and a preparation method thereof. Background Art

[0002] With the development of science and technology, the frequency of plastic use in human life is increasing. The large-scale use of disposable plastics has generated a lot of white garbage. The global ban on plastics has become a global consensus, and recycling and degradable packaging solutions are sought after by people. The packaging materials of disposable products such as household paper and sanitary napkins are discarded by people due to the difficulty of recycling and no recycling value. Compared with traditional polymer materials such as polyethylene (PE) and polypropylene (PP), the water vapor permeability of biodegradable polymer materials is 10 times that of them, and they have natural advantages in replacing them as breathable bottom films for sanitary napkins and diapers.

[0003] Chinese patent application number CN202210361649.0 discloses a biodegradable breathable film and its preparation method, which uses tea polyphenols, thymol and chitosan to give the film certain antibacterial properties, but these substances are easy to migrate, and the complex modification process makes it difficult to scale up. Chinese patent application number CN201210549767.0 discloses a biodegradable PHA breathable film and its preparation method, which uses PHA material to prepare the biodegradable breathable film. PHA itself has high barrier properties and requires high filling to obtain high water vapor permeability. In addition, PHA is fermented from biological secretions, and its production stability is poor. There are still certain problems in the batch production of raw materials. It is easy to breed bacteria and does not meet the hygiene requirements of sanitary napkins and diapers. Chinese patent application number CN201710434392.6 discloses a biodegradable breathable film for diapers and its preparation method, which uses a certain amount of cross-linked polystyrene as a base material. The product does not have full degradation characteristics.

[0004] The biodegradable breathable membrane prepared by the above method is technically difficult to realize, and partial degradation does not meet the high standards of environmental quality required by future society. Summary of the Invention

[0005] Therefore, in response to the above problems, the present invention provides a far-infrared odor-absorbing biodegradable breathable membrane and a preparation method thereof, which solves the problems of complex processes, poor sanitary conditions, and incomplete degradation of preparation materials in the prior art.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A biodegradable breathable film with far infrared absorption and odor absorption, wherein the water vapor permeability coefficient of the biodegradable breathable film with far infrared absorption and odor absorption is 1000g / m 224h-3000g / m 2 24h, a double-layer structure, including an inner layer and an outer layer, wherein the inner layer is a hydrophilic biodegradable modified membrane, and the outer layer is a high-absorption far-infrared biodegradable modified membrane, and the thickness ratio of the inner layer to the outer layer is 1:(1-3); the far-infrared odor-absorbing biodegradable breathable membrane comprises the following raw materials: hydrophilic biodegradable modified granules and high-absorption far-infrared biodegradable modified material;

[0008] The preparation process of the hydrophilic biodegradable modified pellets is as follows: 40%-80% by weight of poly (butylene adipate / terephthalate), 1%-10% by weight of poly (lactic acid), 10%-20% by weight of functional powder, 5%-15% by weight of cellulose, and 0.1%-5% by weight of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed, and then placed in a twin-screw extruder for granulation to obtain the hydrophilic biodegradable modified pellets;

[0009] The preparation process of the high-absorption far-infrared biodegradable modified material is as follows: 40%-80% by weight of poly (butylene adipate / terephthalate), 1%-10% of poly (lactic acid), 5%-15% of functional powder, 5%-10% of zeolite powder, and 0.1%-5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed, and then placed in a twin-screw extruder for granulation to obtain the high-absorption far-infrared biodegradable modified material.

[0010] Furthermore, the molecular weight of the polybutylene adipate / terephthalate is 100,000-300,000, the melt flow rate is 3-5 g / 10 min (190° C., 2160 g), the terminal acid value content is 10-20 mol / t, and the melting point is 110-120° C.

[0011] Furthermore, the polylactic acid has a molecular weight of 50,000-100,000, a melt flow rate of 5-10 g / min (190° C., 2160 g), a melting point of 150-160° C., and an optical purity of ≥98%.

[0012] Furthermore, the functional powder is a mixture of one or more of calcium carbonate, talc, and kaolin in any proportion; the calcium carbonate is 2000-5000 mesh, the talc is 2000-8000 mesh, and the kaolin is 2000-5000 mesh.

[0013] Furthermore, the cellulose is one or a mixture of any proportion of carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose and lignin fiber.

[0014] Furthermore, the zeolite powder is any one of 3A zeolite powder, 4A zeolite powder and 5A zeolite powder.

[0015] Furthermore, the processing aid includes: 0.1-1 parts by weight of a chain extender, 0.1-1 parts by weight of a plasticizer, 0.1-1 parts by weight of an antioxidant and 0.1-1 parts by weight of a lubricant; the chain extender is a mixture of one or more of epoxy soybean oil, glycerol triglycidyl ether, ADR4468, and ADR4400 in any proportion; the plasticizer is a mixture of one or more of tri-n-butyl citrate, acetyl tri-n-butyl citrate, epoxy soybean oil, triacetin, and epoxy fatty acid methyl ester in any proportion; the antioxidant is a hindered phenol or a phosphite; and the lubricant is a mixture of one or more of stearic acid, pentaerythritol stearate, and ethylene bisstearamide in any proportion.

[0016] Furthermore, the operating parameters of the twin-screw extruder are: the temperatures of zones 1 to 7 are 135°C, 145°C, 150°C, 155°C, 155°C, 160°C, and 160°C, respectively, and the rotation speed is 330 rpm.

[0017] A method for preparing a biodegradable breathable film with far-infrared absorption and odor-absorbing properties, comprising the following steps: adding hydrophilic biodegradable modified granules and high-absorption far-infrared biodegradable modified materials into a double-layer co-extrusion film blowing machine, placing the hydrophilic biodegradable modified granules in the inner layer of the double-layer co-extrusion film blowing machine, placing the high-absorption far-infrared biodegradable modified materials in the outer layer of the double-layer co-extrusion film blowing machine, and obtaining the biodegradable breathable film with far-infrared absorption and odor-absorbing properties after film blowing.

[0018] Furthermore, the feeding section temperature of the blown film extruder is 90-120°C, the compression section temperature is 140-170°C, the homogenization section temperature is 150-175°C, the die temperature is 150-175°C, the rotation speed is 20-50rpm, the inflation is 3-6 times, the stretching ratio is 3-6 times, and the inner and outer layer extrusion speed ratio is 1:1-3.

[0019] By adopting the above technical solution, the beneficial effects of the present invention are:

[0020] This technical solution provides a far-infrared, odor-absorbing, and biodegradable breathable membrane that meets the breathability requirements of sanitary napkins and diapers by simply adding common materials such as cellulose and zeolite powder, without the need for complex modification processes. It offers excellent breathability and strength, and the zeolite's porous structure and powerful cation exchange capacity absorb odors through a physical-chemical synergistic effect, while also providing far-infrared heating. Furthermore, the preparation process is simple, requiring no changes to existing processes, making it suitable for large-scale deployment. DETAILED DESCRIPTION

[0021] Example 1

[0022] A biodegradable breathable film with far infrared absorption and odor absorption, wherein the water vapor transmission coefficient of the biodegradable breathable film with far infrared absorption and odor absorption is 1200g / m 2 24h, a double-layer structure, including an inner layer and an outer layer, the inner layer is a hydrophilic biodegradable modified membrane, the outer layer is a high-absorption far-infrared biodegradable modified membrane, and the thickness ratio of the inner and outer layers is 1:1;

[0023] The method for preparing the above-mentioned biodegradable breathable film having far-infrared absorption and odor absorption comprises the following steps:

[0024] (1) Selection of raw materials

[0025] Including the following raw materials: hydrophilic biodegradable modified granules, high adsorption far infrared biodegradable modified materials;

[0026] (1-1) Preparation of hydrophilic biodegradable modified pellets

[0027] 70% by weight of polybutylene adipate / terephthalate, 5% of polylactic acid, 15% of functional powder, 9.5% of cellulose, and 0.5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the hydrophilic biodegradable modified pellets. The operating parameters of the twin-screw extruder are as follows: the temperatures in zones 1 to 7 are 135° C., 145° C., 150° C., 155° C., 155° C., 160° C., and 160° C., respectively, and the speed is 330 rpm.

[0028] The polybutylene adipate / terephthalate has a molecular weight of 100,000, a melt flow rate of 3 g / 10 min (190° C., 2160 g), an end group acid value content of 10 mol / t, and a melting point of 110° C.;

[0029] The polylactic acid has a molecular weight of 500,000, a melt flow rate of 5 g / min (190° C., 2160 g), a melting point of 150° C., and an optical purity of 99%;

[0030] The functional powder is a mixture of calcium carbonate and talc in any proportion; the calcium carbonate is 2000 mesh and the talc is 5000 mesh;

[0031] The cellulose is a mixture of hydroxypropyl methylcellulose and lignin fiber;

[0032] The processing aids include: 0.1 parts by weight of ADR4400, 0.1 parts by weight of epoxidized soybean oil, 0.1 parts by weight of hindered phenols and 0.1 parts by weight of stearic acid;

[0033] (1-2) Preparation of highly adsorbable far-infrared biodegradable modified materials

[0034] 70% by weight of poly (butylene adipate / terephthalate), 10% of poly (lactic acid), 10% of functional powder, 8% of zeolite powder, and 2% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the highly adsorbable far-infrared biodegradable modified material.

[0035] The polybutylene adipate / terephthalate has a molecular weight of 100,000, a melt flow rate of 3 g / 10 min (190° C., 2160 g), an end group acid value content of 10 mol / t, and a melting point of 110° C.;

[0036] The polylactic acid has a molecular weight of 50,000, a melt flow rate of 5 g / min (190° C., 2160 g), a melting point of 150° C., and an optical purity of 99%;

[0037] The functional powder is a mixture of calcium carbonate and talc in any proportion; the calcium carbonate is 2000 mesh and the talc is 5000 mesh;

[0038] The zeolite powder is 3A zeolite powder;

[0039] The processing aids include: 0.1 parts by weight of ADR4400, 0.1 parts by weight of epoxidized soybean oil, 0.1 parts by weight of hindered phenols and 0.1 parts by weight of stearic acid;

[0040] (2) Preparation of biodegradable breathable membrane with far infrared absorbing odor

[0041] The hydrophilic biodegradable modified pellets and the high-absorption far-infrared biodegradable modified material are added into a double-layer co-extrusion film blowing machine, wherein the hydrophilic biodegradable modified pellets are placed in the inner layer of the double-layer co-extrusion film blowing machine, and the high-absorption far-infrared biodegradable modified material is placed in the outer layer of the double-layer co-extrusion film blowing machine. The feeding section temperature of the film blowing extruder is 90° C., the compression section temperature is 140° C., the homogenization section temperature is 150° C., the die temperature is 150° C., the rotation speed is 20 rpm, the blowing times is 0.5, the stretching ratio is 3 times, and the inner and outer layer extrusion speed ratio is 1:1; after film blowing, the biodegradable breathable film with far-infrared absorption and odor absorption is obtained.

[0042] Example 2

[0043] A biodegradable breathable film with far infrared absorption and odor absorption, wherein the water vapor permeability coefficient of the biodegradable breathable film with far infrared absorption and odor absorption is 2100g / m 2 24h, a double-layer structure, including an inner layer and an outer layer, the inner layer is a hydrophilic biodegradable modified membrane, the outer layer is a high-absorption far-infrared biodegradable modified membrane, and the thickness ratio of the inner and outer layers is 1:1;

[0044] The method for preparing the above-mentioned biodegradable breathable film having far-infrared absorption and odor absorption comprises the following steps:

[0045] (1) Selection of raw materials

[0046] Including the following raw materials: hydrophilic biodegradable modified granules, high adsorption far infrared biodegradable modified materials;

[0047] (1-1) Preparation of hydrophilic biodegradable modified pellets

[0048] 70% by weight of polybutylene adipate / terephthalate, 5% of polylactic acid, 19.5% of functional powder, 5% of cellulose, and 0.5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the hydrophilic biodegradable modified pellets. The operating parameters of the twin-screw extruder are as follows: the temperatures in zones 1 to 7 are 135° C., 145° C., 150° C., 155° C., 155° C., 160° C., and 160° C., respectively, and the speed is 330 rpm.

[0049] The polybutylene adipate / terephthalate has a molecular weight of 200,000, a melt flow rate of 4 g / 10 min (190° C., 2160 g), an end group acid value content of 15 mol / t, and a melting point of 115° C.;

[0050] The polylactic acid has a molecular weight of 80,000, a melt flow rate of 8 g / min (190° C., 2160 g), a melting point of 155° C., and an optical purity of 99%.

[0051] The functional powder is a mixture of calcium carbonate and talc in any proportion; the calcium carbonate is 3000 mesh, and the talc is 3000 mesh;

[0052] The cellulose is a mixture of hydroxypropyl methylcellulose and lignin fiber in any proportion;

[0053] The processing aids include: 0.5 parts by weight of ADR4468, 0.5 parts by weight of tri-n-butyl citrate, 0.5 parts by weight of hindered phenols and 0.5 parts by weight of pentaerythritol stearate;

[0054] (1-2) Preparation of highly adsorbable far-infrared biodegradable modified materials

[0055] 70% by weight of poly (butylene adipate / terephthalate), 5% of poly (lactic acid), 10% of functional powder, 10% of zeolite powder, and 5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the highly adsorbable far-infrared biodegradable modified material.

[0056] The polybutylene adipate / terephthalate has a molecular weight of 200,000, a melt flow rate of 4 g / 10 min (190° C., 2160 g), an end group acid value content of 15 mol / t, and a melting point of 115° C.;

[0057] The polylactic acid has a molecular weight of 80,000, a melt flow rate of 8 g / min (190° C., 2160 g), a melting point of 155° C., and an optical purity of 99%.

[0058] The functional powder is a mixture of calcium carbonate and talc in any proportion; the calcium carbonate is 3000 mesh, and the talc is 3000 mesh;

[0059] The zeolite powder is 3A zeolite powder;

[0060] The processing aids include: 0.5 parts by weight of ADR4468, 0.5 parts by weight of tri-n-butyl citrate, 0.5 parts by weight of hindered phenols and 0.5 parts by weight of pentaerythritol stearate;

[0061] (2) Preparation of biodegradable breathable membrane with far infrared absorbing odor

[0062] Hydrophilic biodegradable modified pellets and high-absorption far-infrared biodegradable modified materials are added into a double-layer co-extrusion film blowing machine, wherein the hydrophilic biodegradable modified pellets are placed in the inner layer of the double-layer co-extrusion film blowing machine, and the high-absorption far-infrared biodegradable modified materials are placed in the outer layer of the double-layer co-extrusion film blowing machine. The feeding section temperature of the film blowing extruder is 100° C., the compression section temperature is 150° C., the homogenization section temperature is 155° C., the die temperature is 155° C., the rotation speed is 30 rpm, the inflation is 4 times, the stretching ratio is 4 times, and the inner and outer layer extrusion speed ratio is 1:2; after film blowing, the biodegradable breathable film with far-infrared absorption and odor absorption is obtained.

[0063] Example 3

[0064] A biodegradable breathable film with far infrared absorption and odor absorption, wherein the water vapor permeability coefficient of the biodegradable breathable film with far infrared absorption and odor absorption is 3000g / m 2 24h, a double-layer structure, including an inner layer and an outer layer, the inner layer is a hydrophilic biodegradable modified membrane, the outer layer is a high-absorption far-infrared biodegradable modified membrane, and the thickness ratio of the inner layer to the outer layer is 1:2;

[0065] The method for preparing the above-mentioned biodegradable breathable film having far-infrared absorption and odor absorption comprises the following steps:

[0066] (1) Selection of raw materials

[0067] Including the following raw materials: hydrophilic biodegradable modified granules, high adsorption far infrared biodegradable modified materials;

[0068] (1-1) Preparation of hydrophilic biodegradable modified pellets

[0069] 50% by weight of polybutylene adipate / terephthalate, 10% of polylactic acid, 20% of functional powder, 15% of cellulose, and 5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the hydrophilic biodegradable modified pellets. The operating parameters of the twin-screw extruder are as follows: the temperatures in zones 1 to 7 are 135° C., 145° C., 150° C., 155° C., 155° C., 160° C., and 160° C., respectively, and the speed is 330 rpm.

[0070] The polybutylene adipate / terephthalate has a molecular weight of 300,000, a melt flow rate of 5 g / 10 min (190° C., 2160 g), an end group acid value content of 20 mol / t, and a melting point of 120° C.;

[0071] The polylactic acid has a molecular weight of 100,000, a melt flow rate of 10 g / min (190° C., 2160 g), a melting point of 160° C., and an optical purity of 99%.

[0072] The functional powder is a mixture of calcium carbonate and kaolin in any proportion; the calcium carbonate is 3000 mesh, and the kaolin is 3000 mesh;

[0073] The cellulose is a mixture of hydroxyethyl cellulose and hydroxypropyl methyl cellulose in any proportion;

[0074] The processing aids include: 0.5 parts by weight of epoxidized soybean oil, 0.5 parts by weight of acetyl tri-n-butyl citrate, 0.5 parts by weight of hindered phenols and 0.5 parts by weight of pentaerythritol stearate;

[0075] (1-2) Preparation of highly adsorbable far-infrared biodegradable modified materials

[0076] 60% by weight of poly (butylene adipate / terephthalate), 10% of poly (lactic acid), 15% of functional powder, 10% of zeolite powder, and 5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the highly adsorbable far-infrared biodegradable modified material.

[0077] The polybutylene adipate / terephthalate has a molecular weight of 300,000, a melt flow rate of 5 g / 10 min (190° C., 2160 g), an end group acid value content of 20 mol / t, and a melting point of 120° C.;

[0078] The polylactic acid has a molecular weight of 100,000, a melt flow rate of 10 g / min (190° C., 2160 g), a melting point of 160° C., and an optical purity of 99%.

[0079] The functional powder is a mixture of calcium carbonate and kaolin in any proportion; the calcium carbonate is 3000 mesh, and the kaolin is 3000 mesh;

[0080] The zeolite powder is 5A zeolite powder;

[0081] The processing aids include: 0.5 parts by weight of epoxidized soybean oil, 0.5 parts by weight of acetyl tri-n-butyl citrate, 0.5 parts by weight of hindered phenols and 0.5 parts by weight of pentaerythritol stearate;

[0082] (2) Preparation of biodegradable breathable membrane with far infrared absorbing odor

[0083] The hydrophilic biodegradable modified pellets and the high-absorption far-infrared biodegradable modified material are added into a double-layer co-extrusion film blowing machine, wherein the hydrophilic biodegradable modified pellets are placed in the inner layer of the double-layer co-extrusion film blowing machine, and the high-absorption far-infrared biodegradable modified material is placed in the outer layer of the double-layer co-extrusion film blowing machine. The feeding section temperature of the film blowing extruder is 120° C., the compression section temperature is 170° C., the homogenization section temperature is 175° C., the die temperature is 175° C., the rotation speed is 50 rpm, the inflation is 5 times, the stretching ratio is 5 times, and the inner and outer layer extrusion speed ratio is 1:3; after film blowing, the biodegradable breathable film with far-infrared absorption and odor absorption is obtained.

[0084] Example 4

[0085] A biodegradable breathable film with far infrared absorption and odor absorption, wherein the water vapor permeability coefficient of the biodegradable breathable film with far infrared absorption and odor absorption is 2500g / m 2 24h, a double-layer structure, including an inner layer and an outer layer, the inner layer is a hydrophilic biodegradable modified membrane, the outer layer is a high-absorption far-infrared biodegradable modified membrane, and the thickness ratio of the inner layer to the outer layer is 1:3;

[0086] The method for preparing the above-mentioned biodegradable breathable film having far-infrared absorption and odor absorption comprises the following steps:

[0087] (1) Selection of raw materials

[0088] Including the following raw materials: hydrophilic biodegradable modified granules, high adsorption far infrared biodegradable modified materials;

[0089] (1-1) Preparation of hydrophilic biodegradable modified pellets

[0090] 60% by weight of polybutylene adipate / terephthalate, 10% of polylactic acid, 15% of functional powder, 14% of cellulose, and 1% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the hydrophilic biodegradable modified pellets. The operating parameters of the twin-screw extruder are as follows: the temperatures in zones 1 to 7 are 135° C., 145° C., 150° C., 155° C., 155° C., 160° C., and 160° C., respectively, and the speed is 330 rpm.

[0091] The polybutylene adipate / terephthalate has a molecular weight of 300,000, a melt flow rate of 5 g / 10 min (190° C., 2160 g), an end group acid value content of 20 mol / t, and a melting point of 120° C.;

[0092] The polylactic acid has a molecular weight of 100,000, a melt flow rate of 10 g / min (190° C., 2160 g), a melting point of 160° C., and an optical purity of 99%.

[0093] The functional powder is a mixture of calcium carbonate, talc and kaolin in any proportion; the calcium carbonate is 3000 mesh, the talc is 3000 mesh, and the kaolin is 3000 mesh;

[0094] The cellulose is a mixture of hydroxypropyl methylcellulose and lignin fiber in any proportion;

[0095] The processing aid comprises: 1 part by weight of glycerol triglycidyl ether, 1 part by weight of epoxy fatty acid methyl ester, 1 part by weight of phosphites and 1 part by weight of ethylene bisstearamide;

[0096] (1-2) Preparation of highly adsorbable far-infrared biodegradable modified materials

[0097] 60% by weight of poly (butylene adipate / terephthalate), 10% of poly (lactic acid), 15% of functional powder, 10% of zeolite powder, and 5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed. The mixture is then placed in a twin-screw extruder for granulation to obtain the highly adsorbable far-infrared biodegradable modified material.

[0098] The polybutylene adipate / terephthalate has a molecular weight of 300,000, a melt flow rate of 5 g / 10 min (190° C., 2160 g), an end group acid value content of 20 mol / t, and a melting point of 120° C.;

[0099] The polylactic acid has a molecular weight of 100,000, a melt flow rate of 10 g / min (190° C., 2160 g), a melting point of 160° C., and an optical purity of 99%.

[0100] The functional powder is a mixture of calcium carbonate, talc and kaolin in any proportion; the calcium carbonate is 3000 mesh, the talc is 3000 mesh, and the kaolin is 3000 mesh;

[0101] The zeolite powder is 4A zeolite powder;

[0102] The processing aid comprises: 1 part by weight of glycerol triglycidyl ether, 1 part by weight of epoxy fatty acid methyl ester, 1 part by weight of phosphites and 1 part by weight of ethylene bisstearamide;

[0103] (2) Preparation of biodegradable breathable membrane with far infrared absorbing odor

[0104] Hydrophilic biodegradable modified pellets and high-absorption far-infrared biodegradable modified materials are added into a double-layer co-extrusion film blowing machine, wherein the hydrophilic biodegradable modified pellets are placed in the inner layer of the double-layer co-extrusion film blowing machine, and the high-absorption far-infrared biodegradable modified materials are placed in the outer layer of the double-layer co-extrusion film blowing machine. The feeding section temperature of the film blowing extruder is 120° C., the compression section temperature is 170° C., the homogenization section temperature is 175° C., the die temperature is 175° C., the rotation speed is 50 rpm, the inflation is 6 times, the stretching ratio is 6 times, and the inner and outer layer extrusion speed ratio is 1:3; after film blowing, the biodegradable breathable film with far-infrared absorption and odor absorption is obtained.

[0105] Comparative Example 1

[0106] The difference from Example 1 is that only polybutylene adipate / terephthalate (PBAT) and polylactic acid (PLA) are used as raw materials, and the structure is single-layer. Other technical solutions are the same as those in Example 1.

[0107] Comparative Example 2

[0108] The difference from Example 2 is that only polybutylene adipate / terephthalate (PBAT) and polylactic acid (PLA) are used as raw materials, and the structure is single-layer. Other technical solutions are the same as those in Example 2.

[0109] Comparative Example 3

[0110] The difference from Example 3 is that only polybutylene adipate / terephthalate (PBAT) and polylactic acid (PLA) are used as raw materials, and the structure is single-layer. Other technical solutions are the same as those in Example 3.

[0111] Comparative Example 4

[0112] The difference from Example 4 is that only polybutylene adipate / terephthalate (PBAT) and polylactic acid (PLA) are used as raw materials, and the structure is single-layer. Other technical solutions are the same as those in Example 4.

[0113] Unless otherwise specified, the raw materials used in the present invention are all from common commercially available medicines in this field. The instruments and devices used in the present invention are also conventional instruments and equipment in this field. The test method for the water vapor permeability coefficient of the indicator involved in the present invention is: in accordance with the GB / T1037-2021 standard, the water vapor permeability of the film is measured using a W3 / 031 water vapor permeability tester, the test temperature is 38°C, the humidity is 90RH%, and 5 parallel samples are tested for each group of samples. In accordance with the GB / T 1040.3-2006 standard, the tensile strength of the film is measured using a CMT4204 universal mechanical testing machine, the test speed is 300mm / min, and 5 parallel samples are tested for each group of samples. In accordance with GB / T 4744, the hydrostatic pressure of the film is measured using the SDL Atlas hydrostatic pressure testing equipment, and 5 parallel samples are tested for each group of samples.

[0114] The test data of Example 1, Example 2, Example 3, Example 4, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4 are shown in Table 1.

[0115] Table 1

[0116]

[0117]

[0118] According to analysis and testing, the water vapor permeability of the far-infrared, odor-absorbing, biodegradable breathable film is significantly greater than that of the PBAT / PLA film, and the tensile strength is also significantly greater than that of the PBAT / PLA film. The hydrostatic pressure of the film is ≥60mmH2O, which meets the needs of sanitary napkins and diapers.

[0119] Although the present invention has been particularly shown and described in conjunction with preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims, and all such changes are within the scope of protection of the present invention.

Claims

1. A biodegradable breathable film with far infrared absorbing odor, characterized in that: The water vapor transmission coefficient of the far infrared odor-absorbing biodegradable breathable film is 1000 g / m 2 24h-3000g / m 2 24h, a double-layer structure, including an inner layer and an outer layer, the inner layer is a hydrophilic biodegradable modified membrane, the outer layer is a highly adsorbable far-infrared biodegradable modified membrane, and the thickness ratio of the inner layer to the outer layer is 1:(1-3); the far-infrared odor-absorbing biodegradable breathable membrane comprises the following raw materials: Hydrophilic biodegradable modified granules, high adsorption far-infrared biodegradable modified materials; The preparation process of the hydrophilic biodegradable modified pellets is as follows: 40%-80% by weight of poly (butylene adipate / terephthalate), 1%-10% by weight of poly (lactic acid), 10%-20% by weight of functional powder, 5%-15% by weight of cellulose, and 0.1%-5% by weight of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed, and then placed in a twin-screw extruder for granulation to obtain the hydrophilic biodegradable modified pellets; The preparation process of the high-absorption far-infrared biodegradable modified material is as follows: 40%-80% by weight of poly (butylene adipate / terephthalate), 1%-10% of poly (lactic acid), 5%-15% of functional powder, 5%-10% of zeolite powder, and 0.1%-5% of a processing aid are placed in a three-dimensional mixer and stirred until uniformly mixed, and then placed in a twin-screw extruder for granulation to obtain the high-absorption far-infrared biodegradable modified material.

2. The biodegradable breathable membrane with far infrared absorption and odor absorption according to claim 1, characterized in that: The polybutylene adipate / terephthalate has a molecular weight of 100,000-300,000, a melt flow rate of 3-5 g / 10 min (190° C., 2160 g), an end group acid value content of 10-20 mol / t, and a melting point of 110-120° C.

3. The biodegradable breathable membrane with far infrared absorption and odor absorption according to claim 1, characterized in that: The polylactic acid has a molecular weight of 50,000-100,000, a melt flow rate of 5-10 g / min (190° C., 2160 g), a melting point of 150-160° C., and an optical purity of ≥98%.

4. The biodegradable breathable membrane with far infrared absorption and odor absorption according to claim 1, characterized in that: The functional powder is a mixture of one or more of calcium carbonate, talc and kaolin in any proportion; the calcium carbonate has a mesh size of 2000-5000, the talc has a mesh size of 2000-8000, and the kaolin has a mesh size of 2000-5000.

5. The far-infrared odor-absorbing biodegradable breathable membrane according to claim 1, characterized in that: The cellulose is one or a mixture of carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose and lignin fiber in any proportion.

6. The biodegradable breathable membrane with far infrared absorption and odor absorption according to claim 1, characterized in that: The zeolite powder is any one of 3A zeolite powder, 4A zeolite powder and 5A zeolite powder.

7. The biodegradable breathable membrane with far infrared absorption and odor absorption according to claim 1, characterized in that: The processing aids include: 0.1-1 parts by weight of a chain extender, 0.1-1 parts by weight of a plasticizer, 0.1-1 parts by weight of an antioxidant, and 0.1-1 parts by weight of a lubricant; the chain extender is one or a mixture of any proportion of epoxy soybean oil, glycerol triglycidyl ether, ADR4468, and ADR4400; the plasticizer is one or a mixture of any proportion of tri-n-butyl citrate, acetyl tri-n-butyl citrate, epoxy soybean oil, triacetin, and epoxy fatty acid methyl ester; the antioxidant is a hindered phenol or a phosphite; and the lubricant is one or a mixture of any proportion of stearic acid, pentaerythritol stearate, and ethylene bisstearamide.

8. The biodegradable breathable membrane with far infrared absorption and odor absorption according to claim 1, characterized in that: The operating parameters of the twin-screw extruder are as follows: the temperatures of zones 1 to 7 are 135°C, 145°C, 150°C, 155°C, 155°C, 160°C, and 160°C, respectively, and the rotation speed is 330 rpm.

9. A method for preparing a biodegradable breathable membrane with far-infrared absorption and odor absorption, characterized in that: The following steps are involved: The hydrophilic biodegradable modified granules and the high-absorption far-infrared biodegradable modified material are added into a double-layer co-extrusion film blowing machine, the hydrophilic biodegradable modified granules are placed in the inner layer of the double-layer co-extrusion film blowing machine, and the high-absorption far-infrared biodegradable modified material is placed in the outer layer of the double-layer co-extrusion film blowing machine. After film blowing, the far-infrared odor-absorbing biodegradable breathable film is obtained.

10. The method for preparing a biodegradable breathable film capable of absorbing far-infrared odors according to claim 9, characterized in that: The feeding section temperature of the film blowing extruder is 90-120°C, the compression section temperature is 140-170°C, the homogenization section temperature is 150-175°C, the die temperature is 150-175°C, the rotation speed is 20-50rpm, the inflation is 3-6 times, the stretching ratio is 3-6 times, and the inner and outer layer extrusion speed ratio is 1:1-3.

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