RU2756069C1 - Method for obtaining a high-density polymer ud structure for individual means of armor protection and armoring curved surfaces - Google Patents

Abstract

FIELD: material engineering.

SUBSTANCE: invention relates to methods for obtaining high-density polymer UD structures for armoring curved surfaces, in particular various means of armor protection. To obtain a polymer UD structure, several polymer layers are placed one above the other, and a multilayer coating is formed. The multilayer coating is subjected to heat treatment with pressing at an operating temperature from 115 to 118°C. The layers of the multilayer coating are joined together to form the outer layers of heat treatment and thereby obtain a high-density polymer UD structure.

EFFECT: mechanical rigidity of the material is reduced, which is necessary for the bending of the ballistic fabric with a complex geometry of the armored surface.

9 cl, 5 dwg

Description

The invention relates to methods for producing high-density polymer UD-structures for armoring curved surfaces, in particular various means of armor [F41H1 / 00, F41H5 / 00, B29C43 / 00].

From the prior art there is a METHOD FOR HEATING THE RAW TAPE FOR ITS CONTINUOUS VULCANIZATION ON A HORIZONTALLY LOCATED CALANDER [RU2015154177, publ. 06/21/2017]. in which the cylindrical part of the calender is heated from the inside, and the wet strip is pressed against the outer cylindrical surface of the calender and moved with it by an endless mesh, part of which is pressed against the calender by a pair of pressure cylinders, which are located parallel to the calender axis at a distance from each other along the arc of the calender circumference 90 ° , and the pressed part of the mesh is placed between these cylinders on a calender on an arc of the same 270 ° circle, while the mesh is pulled and pressed against the calender by a separate tension cylinder parallel to the calender, and the calender is equipped with a rotary drive, characterized in that the outer surface of the calender is heated by infrared radiation maintaining its temperature at 250 ° C, directing it directly to this surface between the pressure cylinders, placing a three-phase TSC motionlessly between them and continuously measuring the temperature of the calender surface with a pyrometer in the upper part of its end, and the wet tape is heated with infrared radiation, maintaining its temperature 250 ° C, directing it to both flat surfaces of the tape with a single-phase TSC before vulcanization, continuously measuring the temperature of the flat surface of the green tape in contact with the heated surface of the calender, while the three-phase TSC is made of linear emitters of limited length in reflectors that are mounted along the circumference of the calender without gaps , and a single-phase TSC is made of IKZ-500 lamps, placing them without gaps between the bulbs above the tape with a uniform gap relative to it and under the tape with a uniform gap relative to it, and both TSC are electrically connected, each to its own, to the controlled output of the ARNT, and their the control inputs are connected to the outputs of the corresponding pyrometers, and the pyrometer is fixedly placed in the first quarter on top of the thickness of the end of the cylindrical surface of the calender.

The disadvantages of the analog are:

- the technical difficulty of implementing the method due to the fact that the outer surface of the calender must be heated with infrared radiation to a temperature of 250 ° C; which requires the use of additional functional elements such as emitters, reflectors, pyrometers, etc.

- narrow area of application due to the fact that the surface of the calender is heated to a temperature of 250 ° C. The presence of such a temperature can adversely affect the characteristics of a number of materials used, which lose their useful properties and undergo thermomechanical destruction when heated to a specified temperature.

Also known from the prior art FLEXIBLE ARMOR [RU198813, publ. 07/29/2020] containing armor elements made of layers of material from unidirectional fibers, bonded to each other in mutually transverse directions with a binder, characterized in that said armor is made in the form of a flexible multilayer armor panel with a surface density of 11.5-12.0 kg / m from separate multilayer armor elements with a surface density of at least 0.93 kg / m, while the armor elements are aligned with each other so that the fibers of the upper layer of the previous armor element are directed in the transverse direction to the fibers of the lower layer of the subsequent armor element.

The disadvantages of the analog are:

- a narrow area of application due to the fact that separate multilayer armor elements with a surface density of at least 0.93 kg / m are used, which have a large mass and are unsuitable for use for wearable means of armor protection (for example, body armor);

- low strength due to the fact that the materials are bonded together with a binder, without the use of additional heat treatment, which can ensure the integrity of the entire structure and increase its strength.

The closest in technical essence is the BALLISTIC TISSUE USING ONE-DIRECTIONAL ARAMID SHEET AND POLYETHYLENE FILM, AND THE METHOD OF ITS MANUFACTURE [US2016297184 (A1), publ. in one direction, perpendicularly, the polyethylene film, which plays both the role of a binder and the role of protecting the surface of the sheet, is located between the layers of aramid multifilament to make the layer, and the layer is inserted into the mold and subjected to a pressing and cooling process, thereby producing a ballistic fabric.

The main technical problem of the prototype is the high mechanical rigidity of the resulting material due to the fact that the manufacturing process includes pressing under high temperature and cooling. At the same time, exposure to high temperatures and subsequent cooling gives the material a high rigidity, while limiting its flexibility and the possibility of bending. All of the above limits the application of the claimed method in conditions when it is necessary to carry out bending of the ballistic tissue with a complex geometry of the armored surface.

The objective of the invention is to eliminate the disadvantages of the prototype.

The technical result of the invention is to reduce the mechanical rigidity of the material.

The specified technical result is achieved due to the fact that the method of obtaining a polymer UD-structure of high density for individual means of armor protection and armoring of curved surfaces, characterized in that initially several polymer layers are placed one above the other, while forming a multilayer coating, then the multilayer coating is subjected to heat treatment with pressing at an operating temperature of 115 to 118 ° C, during which the layers of the multilayer coating are joined together to form the outer layers of heat treatment, thereby obtaining a high-density polymer UD-structure.

In particular, the layers of the multilayer coating are formed from UD high modulus polyethylene with a basis weight of 140 to 160 g / m ² .

In particular, the layers of the multilayer coating are formed from UD aramid material with a basis weight of 220 to 240 g / m ² .

In particular, the layers of the multilayer coating are formed from UD high modulus polyethylene with a ^{basis weight of 140 to 160 g / m 2} and a UD aramid material with a basis weight of 220 to 240 g / m ² .

In particular, if the sum of the basis weights of all layers of the multilayer coating is less than 920 g / m ^2, then the resulting multilayer coating is calendered.

In particular, if the sum of the basis weights of all layers of the multilayer coating is more than 920 g / m ^2, then the resulting multilayer coating is processed on a flatbed heat press.

In particular, a multilayer coating is formed, consisting of not less than two layers and not more than ten layers.

In particular, a high density polymeric UD structure with a thickness of 2 to 6 mm is obtained.

In particular, a high density polymeric UD structure is obtained with a density from 300 g / m ² to 2300 g / m ²

Brief Description of Drawings

FIG. 1 shows a general view of the arrangement of layers UD high modulus polyethylene and UD aramid fiber material.

FIG. 2 is a cross-sectional side view of the placement of the UD layers of high modulus polyethylene and aramid fiber material.

FIG. 3 shows a general view of a device for obtaining a UD polymer structure with a surface density of up to 920 g / m ² .

FIG. 4 shows a general view of a device for obtaining a UD polymer structure with a basis weight of more than 920 g / m ² .

FIG. 5 is a cross-sectional side view of a high density UD composite polymer structure.

The figures indicate:

1 - a layer of high-modulus UD-polyethylene or aramid material; 2 - multilayer coating; 3 - multi-layer coating feeding table; 4 - rotating shafts of heating drums; 5 - flatbed heat press; 6 - high density polymer composite UD structure; 7 - layer of external heat treatment.

Implementation of the invention.

A device for obtaining a polymer composite UD-structure with a surface density of up to 920 g / m ² is a roll calender. The roll calender can include a table for feeding a multi-layer coating 3 and rotating shafts of heating drums 4. In this case, the rotating shafts of heating drums 4 form gaps between themselves, and the inner space of the heating drums is completely filled with oil. There are various options for the arrangement of the rotating shafts of the heating drums 4 relative to each other, in particular: vertically in a line, horizontally in a line, L-shaped, etc. The total number of rotating shafts of the heating drums 4 can be from two or more. In this case, the roll calender is configured to set the temperature of the working surfaces of the rotating shafts of the heating drums 4 115-118 ° C by adjusting the temperature of the oil inside the heating drums. Additionally, the roll calender can contain a motorized material feed module, holders of multilayer materials, sections of the feed table, the dispensing table, and other elements. The roll calender allows the production of a polymer composite UD-structure with a surface density of up to 920 g / m ² in the form of rolls.

In embodiments, it is possible to use typical industrial roll calenders that meet the required temperature conditions of the working surfaces of the rotating shafts of the heating drums 4 and the required overall dimensions of the processed polymer structure.

A device for obtaining a polymer UD-structure with a surface density of more than 920 g / m ² is a flatbed calender or flatbed heat press 5, including at least two horizontal working surfaces (thermoelement), which are made with the possibility of closing together. In this case, the flatbed thermopress 5 is made with the ability to set the temperature of the thermoelements 115-118 ° C. Tablet thermopress 5 includes mechanisms for closing and opening working surfaces, which can be pneumatic cylinders, electric drives, etc. In the implementation options, it is possible to use typical industrial flatbed thermopresses 5 that satisfy the required temperature regime of thermoelements and the required overall parameters of the processed polymer structure. The flatbed calender allows the production of a polymer composite structure with a surface density of more than 920 g / m ² in the form of finished parts, which simplifies the production and assembly of finished products.

A method of obtaining a polymer UD-structure of high density for individual means of armor protection and armoring of curved surfaces, characterized by the fact that initially several layers (from two) of UD high-modulus polyethylene with a surface density of 140 to 160 g / m ² and / or UD of aramid material with basis weight from 220 to 240 g / m ² 1, layers 1 are placed one above the other, thereby forming a multilayer coating 2 (shown in Fig. 3).

Further, if it is required to obtain a polymer UD-structure with a surface density of up to 920 g / m ^{2, the} obtained multilayer coating 2 is passed sequentially through at least two gaps of two rotating shafts of the heating drums 4 of the calender (shown in Fig. 4). In this case, the working surfaces of the rotating shafts of the heating drums 4 are preheated to an operating temperature of 115-118 ° C.

If it is required to obtain a UD polymer structure with a surface density of more than 920 g / m ^{2, the} obtained multilayer coating 2 is treated with a flatbed heat press 5 by closing the heated thermoelements together. In this case, the thermoelements of the flatbed 5 thermopress are preheated to an operating temperature of no more than 115-118 ° C.

Further, in the course of processing by calendering or thermal pressing, the layers of UD high-modulus polyethylene or UD aramid material 1 are interconnected, thereby forming a high-density polymeric UD-structure 6 with a thickness of 2 to 6 mm. At the same time, due to heat treatment with a given operating temperature (115-118 ° C), only the layers of external heat treatment 7 located on the outer sides of the original UD polymer structure of high density 6 are subject to partial thermomechanical destruction (melting) (which, in a given temperature regime, does not significantly affect the total value surface density). Thus, the layers are sintered without changing the physical ballistic properties of the threads of high-modulus polyethylene or aramid material, while maintaining the form-forming properties.

The technical result of the invention, the reduction of mechanical rigidity is achieved due to the fact that during processing by calendering or thermal pressing at temperatures from 115 ° C to 118 ° C, the layers UD of high-modulus polyethylene or UD of aramid material 1 are interconnected, thereby forming a polymer UD-structure of high density 6 with a thickness of 2 to 6 mm. Due to heat treatment at a given operating temperature, the layers 1 are joined without losing their elastic properties and the possibility of bending, while the layers of external heat treatment 7 located on the outer sides of the original UD polymer structure of high density 6 are partially melted with the acquisition of form-forming properties. Thus, the obtained polymer UD-structure of high density 6 has a reduced index of mechanical rigidity, corresponding to the original multilayer coating 2 while maintaining the overall value of the basis weight. Implementation of the piled-up method makes it possible to obtain structures of high density (from 300 g / m ² to 2300 g / m ² ) with reduced mechanical rigidity for armoring the surfaces of objects with false geometry, such as individual body armor and curved surfaces.

Consider a variant of achieving a technical result, for example, initially, there is a multilayer coating 2 consisting of five layers of high-modulus UD-polyethylene. Each layer of high-modulus UD-polyethylene has a basis weight of 150 g / m ² . Thus, a multi-layer coating of five layers has a basis weight of 750 g / m ² . Since the value of 750 g / m ^{2 is} less than 920 g / m ² , the obtained multilayer coating 2 is passed successively through two gaps of two rotating shafts of the heating drums 4 of the calender with temperatures of the working surfaces of 117 ° C. At the exit of the calender, we have a high density UD polymer structure 6 with an areal density of 750 g / m ² , while the first and fifth layers are forming layers of external heat treatment 7, and the second third and fourth layers are connected together with the first and fifth into a common structure, possessing, at the same time, a reduced value of mechanical rigidity in comparison with methods when heat treatment is carried out at higher temperatures. After obtaining the UD, the high density polymer structure 6 can be used to arm various curved surfaces, for example, body armor.

In 2021, the applicant implemented the claimed method, the approbation and testing of which confirmed the claimed technical result. At the same time, the following was revealed:

- layers of external heat treatment 7 ensure the integrity and rigidity of the entire structure, while maintaining flexibility due to interconnected internal layers that have not lost their elastic properties and provide the ability to bend the entire structure;

- polymer UD-structure high-density 6 has an increased surface density value (300 g / m ² when used originally two layers of high modulus polyethylene or aramid fiber 1 to 2300 g / m ² when used ten layers of high modulus polyethylene, or aramid fiber material 1);

- Polymer UD-structure of high density 6 additionally has increased bullet resistance and resistance to over-blocking impact;

- it is possible to create a polymeric UD-structure of high density 6 with the required surface density. Considering that one layer of high-modulus polyethylene has a surface density of 150 g / m ² , it is possible to obtain: a polymer structure of two layers with a density of 300 g / m ² ;

polymer structure of three layers with a density of 450 g / m ² ;

polymer structure of four layers with a density of 600 g / m ² ;

a polymer structure of five layers with a density of 750 g / m ² ;

polymer structure of six layers with a density of 900 g / m ² ;

polymer structure of seven layers with a density of 1050 g / m ² ;

a polymer structure of eight layers with a density of 1200 g / m ² ;

a polymer structure of nine layers with a density of 1350 g / m ² ;

polymer structure of ten layers with a density of 1500 g / m ² .

Considering that one layer of aramid material has an areal density of 230 g / m ² , you can get:

a polymer structure of two layers with a density of 460 g / m ² ;

polymer structure of three layers with a density of 690 g / m ² ;

polymer structure of four layers with a density of 920 g / m ² ;

a polymer structure of five layers with a density of 1150 g / m ² ;

a polymer structure of six layers with a density of 1380 g / m ² ;

a polymer structure of seven layers with a density of 1610 g / m ² ;

a polymer structure of eight layers with a density of 1840 g / m ² ;

polymer structure of nine layers with a density of 2070 g / m ² ;

polymer structure of ten layers with a density of 2300 g / m ² .

- it is possible to create hybrid (layers of high-modulus polyethylene and aramid material are used together in the formation of a multilayer coating 2) uniform ballistic UD-structures in which two materials with different operating principles are used simultaneously, UD-aramid provides increased bullet resistance, and UD-polyethylene (due to its acceptable rigidity) acts as an anti-traumatic agent to remove the over-the-counter impact.

The choice of the operating temperature in the range from 115 ° С to 118 ° С during heat treatment of multilayer coating 2 is justified by the fact that this temperature is sufficient for the high-quality connection of layers of high-modulus UD-polyethylene or aramid material 1 into a polymer composite UD-structure of high density 6 with the formation of forming layers external heat treatment 7 while maintaining the flexibility of the product. When the operating temperature decreases below 115 ° C, sufficient quality of the connection of the layers of high-modulus UD-polyethylene or aramid material 1 is not ensured to form a polymer composite UD-structure of high density 6. When the operating temperature is increased above 118 ° C, excessive thermomechanical destruction (melting) of the layers of the high-modulus occurs. UD-polyethylene or aramid material 1 which critically degrades the surface density value and flexibility of the high-density polymeric composite UD-structure 6.

The limitation of the number of layers from two to ten is justified by the capabilities of modern industrial roll calenders and flatbed heat presses 5, as well as by the maximum thickness of the polymer composite UD-structure of high density 6 suitable for further folding.

The thickness of the high density UD polymer structure 6 from 2 to 6 mm depends on the number of layers used in the multilayer coating 2. With the number of layers equal to ten, the approximate thickness of the structure is approximately 6 mm.

Using a thermal press Tablet 5, if required to obtain UD polymeric structure with a surface density of more than 920 g / m ² based on the fact that at large values of the surface density (more than 920 g / m ²⁾ at the outlet of roll calenders due to standard radii values the rotating shafts of the heating drums 4 are formed deformations and bends of the surfaces of the structure of the polymer material.

Claims (9)

1. A method of obtaining a polymer UD-structure of high density for individual body armor and armoring of curved surfaces, characterized by the fact that initially several polymer layers are placed one above the other, while forming a multilayer coating, then the multilayer coating is subjected to heat treatment with pressing at an operating temperature of 115 up to 118 ° C, during which the layers of the multilayer coating are connected to each other to form the outer layers of heat treatment, thereby obtaining a polymer UD-structure of high density. 2. The method according to claim 1, characterized in that the layers of the multilayer coating are formed from UD high-modulus polyethylene with a surface density of 140 to 160 g / m ² . 3. A method according to claim 1, characterized in that the layers of the multilayer coating are formed from UD aramid material with a basis weight of 220 to 240 g / m ² . 4. The method according to claim 1, characterized in that the layers of the multilayer coating are formed from UD high-modulus polyethylene with a ^{basis weight of 140 to 160 g / m 2} and UD aramid material with a basis weight of 220 to 240 g / m ² . 5. A method according to claims 1-4, characterized in that if the sum of the ^{basis weights of all layers of the multilayer coating is less than 920 g / m 2} , then the obtained multilayer coating is subjected to calendering. 6. A method according to claims 1-4, characterized in that if the sum of the surface densities of all layers of the multilayer coating is more than 920 g / m ² , then the obtained multilayer coating is processed on a flatbed heat press. 7. The method according to claim 1, characterized in that a multilayer coating is formed, consisting of at least two layers and not more than ten layers. 8. A method according to claim 1, characterized in that a high density polymeric UD structure with a thickness of 2 to 6 mm is obtained. 9. A method according to claims 1 and 7, characterized in that a high density polymer UD structure with a density of 300 g / m ² to 2300 g / m ^{2 is} obtained.

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