阅读说明：本技术 一种抗紫外老化的氟树脂氦气阻隔薄膜多层共挤薄膜工艺 (Ultraviolet aging resistant fluororesin helium barrier film multilayer co-extrusion film process ) 是由 不公告发明人 于 2021-08-12 设计创作，主要内容包括：本发明公开了一种抗紫外老化的氟树脂氦气阻隔薄膜多层共挤薄膜工艺。该抗紫外老化的氟树脂氦气阻隔薄膜多层共挤薄膜工艺,采用平挤上吹设备,制备出高性能多层复合氟膜；多层复合氟膜,利用多层结构的优势,最外层氟树脂(或改性氟树脂)耐高低温、耐紫外老化、耐摩擦、耐腐蚀、阻隔水；粘结层链接氟树脂与阻气层,起到良好粘结性能；阻气层采用高性能未改性(或改性)的阻隔材料；三者有机统一制备的多层复合薄膜,采用薄膜吹塑工艺,使含氟树脂复合膜薄膜内高分子横向与纵向呈现有序排列；进一步提高了含氟树脂复合薄膜横向与纵向的耐磨性；改性后的氟树脂,对紫外线有反射或吸收,进一步提高了抗紫外线性能,也可作为临近空间飞艇的防护层或阻隔层。(The invention discloses an ultraviolet aging resistant fluororesin helium barrier film multilayer co-extrusion film process. The anti-ultraviolet aging fluororesin helium barrier film multilayer co-extrusion film process adopts a flat extrusion up-blowing device to prepare a high-performance multilayer composite fluorine film; the multilayer composite fluorine film utilizes the advantages of a multilayer structure, and the outermost layer of fluororesin (or modified fluororesin) has high and low temperature resistance, ultraviolet aging resistance, friction resistance, corrosion resistance and water barrier; the bonding layer is linked with the fluororesin and the gas barrier layer, so that good bonding performance is achieved; the gas barrier layer adopts a high-performance unmodified (or modified) barrier material; the multilayer composite film prepared by organically unifying the three components adopts a film blowing process to ensure that macromolecules in the fluorine-containing resin composite film are orderly arranged in the transverse direction and the longitudinal direction; the transverse and longitudinal wear resistance of the fluorine-containing resin composite film is further improved; the modified fluororesin reflects or absorbs ultraviolet rays, further improves the ultraviolet resistance, and can also be used as a protective layer or a barrier layer of an airship in the adjacent space.)

1. The multilayer co-extrusion film process of the anti-ultraviolet aging fluororesin helium barrier film is characterized by comprising the following steps of:

prefabricating materials: the fluororesin (modified fluororesin) and the ultraviolet shielding agent (organic or inorganic compound) are uniformly mixed and granulated by a melt blending mode.

S1, metering: raw and auxiliary materials such as nylon, polyethylene, acid modified polyolefin compound, ethylene tetrafluoroethylene polymer and the like (wherein the raw and auxiliary materials are all granular) are manually added into a hopper of an extruder, and are automatically metered and mixed according to a specific proportion.

S2, drying: before processing, the high polymer with moisture absorption tendency needs to be dried at the temperature of about 80-150 ℃ for about 4-24 hours, and the moisture content of the dried polymer slices is required to be controlled below 50 ppm.

S3, feeding, adding materials and extruding: when the temperature of the extruder and the head reaches the heat preservation requirement (namely, the temperature is 220-310 ℃), starting the extruder, adding a small amount of raw and auxiliary materials into a hopper, rotating a screw at a low speed at the beginning, gradually increasing the rotating speed of the screw after a molten material passes through the head and is blown into a tube bubble, simultaneously filling the material, combining fluororesin (or modified fluororesin) with other resin by using customized multilayer extrusion equipment to prepare a multilayer co-extruded film, and simultaneously, cooling water is used for carrying out uninterrupted circulating cooling on an extruder motor to ensure that the extruder motor is within a safe temperature.

S4, filtering and removing impurities: in order to remove impurities, gel particles, fish eyes and other foreign matters possibly existing in the melt, a filter is usually installed on the melt pipeline before and after the metering pump, a disc-shaped filter is usually adopted in the film production line, the material is formed by combining a stainless steel mesh and a stainless steel sintered felt, the size of the stainless steel disc is phi 12 inches, and the aperture of the filter mesh is generally set to be 10-30 mu.

S5, mixing and controlling temperature: when the melt raw material flows through the melt pipe, the temperature of the melt along the pipe wall and the temperature of the melt center are limited by the distance, so that a large temperature difference exists between the melt raw material and the melt, in order to ensure uniform temperature of the melt entering the die head and uniform discharge of the die head, a plurality of groups of static mixers are required to be arranged inside one end of the melt pipe connected with the die head, and when the melt flows through the static mixers, the uniform mixing action of separation-combination-separation-combination can be automatically generated, so that the temperature of a melt machine head is about 210-310 ℃.

S6, shaping: the melted resin is longitudinally stretched under the action of mechanical force of extrusion blow molding in an extruder, and is transversely stretched by compressed air blowing so that the multilayer composite film is blown into a film, and then the film is co-extruded by a plurality of extruders carried by the multilayer film extruder and is extruded by the same machine head; and cooling, mechanically and automatically drawing, stretching, shaping and rolling the multilayer film in the cooling line by matching a fan arranged on the extruder with a cooling ring arranged on the machine head to prepare the multilayer film.

S7, cutting, flattening, rolling and subsequent inspection: the film after shaping is rolled by a multi-roller shaft of the multilayer film extruder, the shaped film is trimmed by edge trimming equipment of the multilayer film extruder, and the trimmed film is flattened and rolled by a flattening machine.

S8, checking: and cutting a plurality of samples with the length of about 5m before and after the multilayer composite film is rolled, and inspecting.

S9, packaging and warehousing: sticking the multilayer composite film which meets the relevant requirements and does not meet the relevant requirements after inspection to a sample, packaging the film which meets the relevant requirements, and entering a finished product raw material area; and sticking labels on the films which do not meet the relevant requirements, and putting the films into a finished product raw material area for independent storage.

2. The ultraviolet aging resistant fluororesin helium barrier film multilayer co-extrusion film process according to claim 1, which is characterized in that: in the S4 process, the heating temperature of the disc-shaped filter adopted in the multi-layer film extruder is controlled between 270 ℃ and 310 ℃.

3. The ultraviolet aging resistant fluororesin helium barrier film multilayer co-extrusion film process according to claim 1, which is characterized in that: in the operation of S8, the corrosion resistance, temperature resistance, gas permeability, mechanical property, tensile property, ultraviolet aging resistance, adhesive property and heat sealing property of the film are respectively tested.

Technical Field

The invention relates to the technical field of high-altitude balloons, in particular to an ultraviolet aging resistant fluororesin helium barrier film multilayer co-extrusion film process.

Background

The prior art is mainly based on conventional structures, such as: multilayer composite films of LLDPE; the helium or hydrogen barrier film prepared from special PET and other materials is mainly applied to key parts such as a high-altitude balloon, a helium barrier layer of an adjacent space aerostat and the like, and has a conventional structure: LLDPE/AD/EVOH/AD/LLDPE or special PET monolayer; other films containing EVOH obstruct helium or hydrogen, and the principle is as follows: the principle of helium gas blocking by the multilayer or single-layer film is that gas molecules are blocked by a tortuous channel with a fine structure in the film.

However, in practical use, there still exist some disadvantages: LLDPE is linear low density polyethylene, and has good toughness, but low mechanical strength and small force action among molecules, so that the material has poor performances such as heat sealing, gas barrier and corrosion resistance, and meanwhile, the ultraviolet resistance degree of the LLDPE is obviously poor, and the LLDPE cannot meet the long-term use in a complex environment.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides an ultraviolet aging resistant fluororesin helium barrier film multilayer co-extrusion film process, which solves the problems of poor corrosion resistance, high and low temperature aging resistance, low mechanical strength, poor helium or hydrogen barrier property and ultraviolet aging of film materials.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: an anti-ultraviolet aging fluororesin helium barrier film multilayer co-extrusion film process comprises the following steps:

prefabricating materials: the fluororesin (modified fluororesin) and the ultraviolet shielding agent (organic or inorganic compound) are uniformly mixed and granulated by a melt blending mode.

S1, metering: raw and auxiliary materials such as nylon, polyethylene, acid modified polyolefin compound, ethylene tetrafluoroethylene polymer and the like (wherein the raw and auxiliary materials are all granular) are manually added into a hopper of an extruder, and are automatically metered and mixed according to a specific proportion.

S2, drying: before processing, the high polymer with moisture absorption tendency needs to be dried at the temperature of about 80-150 ℃ for about 4-24 hours, and the moisture content of the dried polymer slices is required to be controlled below 50 ppm.

S3, feeding, adding materials and extruding: when the temperature of the extruder and the head reaches the heat preservation requirement (namely, the temperature is 220-310 ℃), starting the extruder, adding a small amount of raw and auxiliary materials into a hopper, rotating a screw at a low speed at the beginning, gradually increasing the rotating speed of the screw after a molten material passes through the head and is blown into a tube bubble, simultaneously filling the material, combining fluororesin and other resins by using customized multilayer extrusion equipment to prepare a multilayer co-extruded film, and simultaneously performing uninterrupted circulating cooling on an extruder motor by using cooling water to ensure that the extruder motor is within a safe temperature.

S4, filtering and removing impurities: in order to remove impurities, gel particles, fish eyes and other foreign matters possibly existing in the melt, a filter is usually installed on the melt pipeline before and after the metering pump, a disc-shaped filter is usually adopted in the film production line, the material is formed by combining a stainless steel mesh and a stainless steel sintered felt, the size of the stainless steel disc is phi 12 inches, and the aperture of the filter mesh is generally set to be 10-30 mu.

S5, mixing and controlling temperature: when the melt raw material flows through the melt pipe, the temperature of the melt along the pipe wall and the temperature of the melt center are limited by the distance, so that a large temperature difference exists between the melt raw material and the melt, in order to ensure uniform temperature of the melt entering the die head and uniform discharge of the die head, a plurality of groups of static mixers are required to be arranged inside one end of the melt pipe connected with the die head, and when the melt flows through the static mixers, the uniform mixing action of separation-combination-separation-combination can be automatically generated, so that the temperature of a melt machine head is about 210-310 ℃.

S6, shaping: the melted resin is longitudinally stretched under the action of mechanical force of extrusion blow molding in an extruder, and is transversely stretched by compressed air blowing so that the multilayer composite film is blown into a film, and then the film is co-extruded by a plurality of extruders carried by the multilayer film extruder and is extruded by the same machine head; and cooling, mechanically and automatically drawing, stretching, shaping and rolling the multilayer film in the cooling line by matching a fan arranged on the extruder with a cooling ring arranged on the machine head to prepare the multilayer film.

S7, cutting, flattening, rolling and subsequent inspection: the film after shaping is rolled by a multi-roller shaft of the multilayer film extruder, the shaped film is trimmed by edge trimming equipment of the multilayer film extruder, and the trimmed film is flattened and rolled by a flattening machine.

S8, checking: and cutting a plurality of samples with the length of about 5m before and after the multilayer composite film is rolled, and inspecting.

S9, packaging and warehousing: sticking the multilayer composite film which meets the relevant requirements and does not meet the relevant requirements after inspection to a sample, packaging the film which meets the relevant requirements, and entering a finished product raw material area; and sticking labels on the films which do not meet the relevant requirements, and putting the films into a finished product raw material area for independent storage.

Preferably, the heating temperature of the disc filter adopted in the multilayer film extruder in the S4 process is controlled to be 270-310 ℃.

Preferably, the corrosion resistance, temperature resistance, gas permeability, mechanical properties, tensile properties, ultraviolet ray aging resistance, adhesive properties and heat sealing properties of the film are respectively tested in the operation of S8.

(III) advantageous effects

The invention provides an anti-ultraviolet-aging fluororesin helium barrier film multilayer co-extrusion film process, which has the following beneficial effects:

the anti-ultraviolet aging fluororesin helium barrier film multilayer co-extrusion film process adopts a flat extrusion up-blowing device to prepare a high-performance multilayer composite fluorine film; the multilayer composite fluorine film utilizes the advantages of a multilayer structure, and the outermost layer of fluororesin is resistant to high and low temperature, ultraviolet aging, friction, corrosion and water; the bonding layer is linked with the fluororesin and the gas barrier layer, so that good bonding performance is achieved; the gas barrier layer adopts a high-performance unmodified (or modified) barrier material; the multilayer composite film prepared by organically unifying the three components adopts a film blowing process to ensure that macromolecules in the fluorine-containing resin composite film are orderly arranged in the transverse direction and the longitudinal direction; further improves the transverse and longitudinal mechanical properties (tensile strength, tensile modulus, breaking strength and breaking elongation) of the fluorine-containing resin composite film; further improving the gas barrier property of the fluorine-containing resin composite film; the transverse and longitudinal wear resistance of the fluorine-containing resin composite film is further improved; further improving the chemical stability and being used as a barrier layer of an airship in the adjacent space.

Detailed Description

All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The invention provides a technical scheme that: an anti-ultraviolet aging fluororesin helium barrier film multilayer co-extrusion film process comprises the following steps:

s1, metering: raw and auxiliary materials such as nylon, polyethylene, acid modified polyolefin compound, ethylene tetrafluoroethylene polymer and the like (wherein the raw and auxiliary materials are all granular) are manually added into a hopper of an extruder, and are automatically metered and mixed according to a specific proportion.

S2, drying: before processing, the high polymer with moisture absorption tendency needs to be dried at the temperature of about 80-150 ℃ for about 4-24 hours, and the moisture content of the dried polymer slices is required to be controlled below 50 ppm.

S3, feeding, adding materials and extruding: when the extruder and the machine head meet the heat preservation requirement (namely, the temperature is 220-310 ℃), starting the extruder, adding a small amount of raw and auxiliary materials into a hopper, rotating a screw at a low speed at the beginning, gradually increasing the rotating speed of the screw after a molten material passes through the machine head and is blown into a tube bubble, simultaneously filling the material, combining fluororesin and other resins by using a customized multilayer extrusion device to prepare a multilayer co-extruded film, adding a certain amount of titanium-containing master batch chips into a matched molten material in the extrusion of the molten material, and increasing the ultraviolet absorption capacity of the film by distributing titanium dioxide particles after decomposition of the master batch chips in the film.

S4, filtering and removing impurities: in order to remove impurities, gel particles, fish eyes and other foreign matters possibly existing in the melt, a filter is usually installed on the melt pipeline before and after the metering pump, a disc-shaped filter is usually adopted in the film production line, the material is formed by combining a stainless steel mesh and a stainless steel sintered felt, the size of the stainless steel disc is phi 12 inches, and the aperture of the filter mesh is generally set to be 10-30 mu.

S5, mixing and controlling temperature: when the melt raw material flows through the melt pipe, the temperature of the melt along the pipe wall and the temperature of the melt center are limited by the distance, so that a large temperature difference exists between the melt raw material and the melt, in order to ensure uniform temperature of the melt entering the die head and uniform discharge of the die head, a plurality of groups of static mixers are required to be arranged inside one end of the melt pipe connected with the die head, and when the melt flows through the static mixers, the uniform mixing action of separation-combination-separation-combination can be automatically generated, so that the temperature of a melt machine head is about 210-310 ℃.

S6, shaping: the melted resin is longitudinally stretched under the action of mechanical force of extrusion blow molding in an extruder, and is transversely stretched by compressed air blowing so that the multilayer composite film is blown into a film, and then the film is co-extruded by a plurality of extruders carried by the multilayer film extruder and is extruded by the same machine head; and cooling, mechanically and automatically drawing, stretching, shaping and rolling the multilayer film in the cooling line by matching a fan arranged on the extruder with a cooling ring arranged on the machine head to prepare the multilayer film.

S7, cutting, flattening, rolling and subsequent inspection: the film after shaping is rolled by a multi-roller shaft of the multilayer film extruder, the shaped film is trimmed by edge trimming equipment of the multilayer film extruder, and the trimmed film is flattened and rolled by a flattening machine.

S8, checking: and cutting a plurality of samples with the length of about 5m before and after the multilayer composite film is rolled, and inspecting.

S9, packaging and warehousing: sticking the multilayer composite film which meets the relevant requirements and does not meet the relevant requirements after inspection to a sample, packaging the film which meets the relevant requirements, and entering a finished product raw material area; and sticking labels on the films which do not meet the relevant requirements, and putting the films into a finished product raw material area for independent storage.

Wherein, in the S4 process, the heating temperature of a disc-shaped filter adopted in the multilayer film extruder is controlled between 270 ℃ and 310 ℃.

Wherein, in the operation of S8, the corrosion resistance, temperature resistance, gas permeability, mechanical property, tensile property, ultraviolet aging resistance, adhesive property and heat sealing property of the film are respectively tested.

Example 2

The difference from the embodiment 1 is that: in S3, the film of the double-layer or single-layer structure is blown out by setting with an extruder.

Comparative example

Taking 100 parts of raw materials, respectively preparing the raw materials according to examples 1 and 2 and the prior art, measuring the tensile strength, the corrosion resistance, the gas barrier property and the heat seal strength of each part of raw materials after the preparation is completed, randomly sampling the samples of example 1 and placing the samples in a container I, randomly sampling the samples of example 2 and placing the samples in a container 2, randomly sampling the samples in the prior art and placing the samples in a container 3, and specifically referring to the following table:

container number	1	2	3
				High and low temperature resistance	High and low temperature resistance	High and low temperature resistance	Intolerant of high and low temperature
Degree of ultraviolet aging resistance	Very resistant to ageing	Aging resistance	Is not resistant to aging
				Gas barrier property	Extremely strong	Is stronger	Is poor
Heat-sealing reinforcement	Extremely strong	Is stronger	Is poor
				Corrosion resistance	Extremely corrosion resistant	Is more corrosion resistant	Is not corrosion resistant

In summary, the best performance can be achieved by extruding the film using a multi-layer compounding process.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.