Preparation method of POK and EVOH blending modified high-barrier-property material

Abstract

The invention discloses a preparation method of a POK and EVOH blending modified high-barrier material, which comprises the following steps: pre-drying, uniformly mixing, cooling and curing, air injection for water removal, pelletizing, secondary drying and the like to obtain the POK and EVOH modified high-barrier material, compounding the POK, EVOH and EAA according to a certain proportion to form a three-phase mixed system, and playing a synergistic effect to obtain the POK and EVOH blending modified high-barrier material. The oxygen barrier effect is improved; through the special compatilizer for POK, the compatibility of POK and the EVOH material is improved, and the mechanical property of the material is improved; the oxygen barrier effect of POK at high temperature and high humidity is basically not reduced, and the oxygen barrier effect of the whole system at high temperature and high humidity is improved; the antioxidant system improves the thermal stability of the EVOH material and the POK material during processing, and solves the problems that the materials are easy to decompose during processing and easy to yellow after being used for a long time.

Description

Technical Field

[0001] The present invention relates to the field of high barrier materials, and in particular to a method for preparing a high barrier material modified by blending POK and EVOH. Background Art

[0002] At present, the material with the best oxygen barrier property is ethylene vinyl alcohol copolymer (EVOH). Currently, only about 4 companies in the world can stably mass produce this material. The supply is insufficient and the price has remained high. At present, EVOH material, as an oxygen barrier material, is widely used in films, automobile fuel tanks, oxygen barrier pipes and other fields. Generally, 100% EVOH material is used as a barrier layer, and the EVOH material and the main layer are bonded together by a special hot melt adhesive. Currently, the main companies that can mass produce EVOH material in the world are two Japanese companies and one company in Taiwan Province, China. The production capacity is insufficient, the market is insufficient, and the price has remained high. At the same time, the barrier property of EVOH material to oxygen is greatly affected by temperature and air humidity. With the increase of temperature and humidity, its barrier property to oxygen drops sharply. Therefore, it is necessary to propose a preparation method of a high barrier material modified by blending POK and EVOH. Summary of the invention

[0003] The purpose of the present invention is to solve the problems in the background technology and provide a method for preparing a high barrier material by blending and modifying POK and EVOH.

[0004] The above technical objectives of the present invention are achieved through the following technical solutions: A method for preparing a high barrier material by blending and modifying POK and EVOH, comprising the following steps: S1, pre-drying, pre-drying the hygroscopic components such as EVOH and EAA in POK, EVOH, EAA, POK special compatibilizer, and antioxidant through the steam drying mechanism of the twin-screw granulation equipment (1), and conveying the condensed water generated after drying to the water cooling mechanism; S2, mixing uniformly, heating and melting POK, EVOH, EAA, POK special compatibilizer, and antioxidant through the twin screw mechanism of the twin screw granulation equipment (1) and efficiently mixing to form a mixture, and then extruding it into strips; S3, cooling and solidification, cooling and solidifying the strips through the water cooling mechanism of the twin-screw granulating equipment (1) to form the strips, and the water after the water cooling mechanism absorbs heat is filtered and transported to the steam generator for use in the steam drying mechanism; S4, air jet dehydration, the strips are jetted through the air jet mechanism of the twin-screw granulating device (1) to remove water droplets on the surface; S5, pelletizing, cutting the strips after removing the surface water droplets into uniform pellets through the cutting mechanism of the twin-screw pelletizing device (1); S6, secondary drying, the particles are secondary dried to remove excess water, thereby obtaining a high barrier raw material.

[0005] The present invention compounds the three materials of POK, EVOH and EAA according to a certain ratio to form a three-phase mixed system, which has a synergistic effect and improves the oxygen barrier effect.

[0006] Barrier properties mainly rely on the high crystallinity of the material. After crystallization, the gap between molecules is very small, and small gas molecules are not easy to pass through. POK has good high humidity resistance for EVOH materials. The hydroxyl group of EVOH is hydrophilic. After combining with water, its crystallinity decreases, resulting in a decrease in barrier properties. At the same time, the advantage of POK is that the oxygen barrier property is not affected in the higher temperature range of 60-90℃, while EVOH materials are greatly affected.

[0007] Through material modification, the cost of raw materials can be reduced while ensuring the oxygen barrier effect; Improve the material's barrier effect against oxygen under high temperature and high humidity conditions; Utilize the synergistic effect of POK and EVOH materials on oxygen barrier effect to improve the oxygen barrier effect; Solve the compatibility of POK materials and EVOH materials to ensure the mechanical strength of the materials; The antioxidant system can solve the problem of POK and EVOH materials being prone to aging and yellowing; The present invention dries hygroscopic materials such as POK, EVOH, and EAA in advance to prevent the raw materials from absorbing moisture or containing water before processing, and to prevent the water from being released during the melting process, which may cause the problem of bubbles. If there are bubbles during the melting process, gas or liquid may penetrate through the channels formed by the bubbles, greatly reducing the barrier performance of the material. The materials are then mixed evenly to form an effective barrier network, and then cooled and solidified, pelletized, and dried again to remove surface water, thereby obtaining POK and EVOH modified high-barrier materials.

[0008] The component proportions of the high barrier raw materials are POK 40%-45%, EVOH 40%-45%, POK special compatibilizer 5%-10%, EAA 2%-10%, and antioxidant 1%-5%. The POK special compatibilizer is a modified material based on POK-based resin grafted with maleic anhydride grafts, and the antioxidant is a mixture of two or more hindered phenol-type antioxidants, thioesters or phosphite antioxidants.

[0009] The twin-screw granulating equipment comprises a primary steam drying mechanism, a twin-screw mixing mechanism, a water cooling mechanism, an air jet mechanism, a cutting mechanism, and a secondary steam drying mechanism which are arranged in sequence.

[0010] Preferably, the primary steam drying mechanism includes a discharge box with a top opening, an internally hollow rotating shaft, a first air inlet pipe, an air outlet pipe, and a spiral blade, the rotating shaft is arranged in the inner cavity of the discharge box, the first air inlet pipe is sleeved and fixed on the inner side of the rotating shaft, a water outlet chamber is arranged between the first air inlet pipe and the rotating shaft, the left end of the first air inlet pipe protrudes from the left side of the rotating shaft, the right end of the first air inlet pipe is located in the rotating shaft, the interior of the spiral blade is hollow, the spiral blade is arranged on the outer side wall of the rotating shaft, the air outlet pipe is arranged at the position where the spiral blade is arranged on the rotating shaft, one end of the air outlet pipe is fixedly connected to the first air inlet pipe and is communicated with the inner wall of the first air inlet pipe, the other end of the air outlet pipe is fixedly connected to the rotating shaft and is located in the inner cavity of the spiral blade, and a water outlet hole is also opened at the position where the spiral blade is arranged on the rotating shaft.

[0011] The present invention conveys the steam generated by the steam generator through the first air inlet pipe and the air outlet pipe into the inner cavity of the spiral blade, thereby heating the spiral blade, so that the material falling into the discharge box is dried while being conveyed, and then conveyed to the twin-screw mixing mechanism. The steam after releasing heat is cooled into water and discharged into the water outlet cavity through the water outlet hole, and then discharged through the water outlet pipe, thereby drying the material and keeping the material dry.

[0012] Preferably, the twin-screw mixing mechanism includes a heating barrel, two rotating shafts that can rotate in the heating barrel, and an extrusion die head arranged at the end of the heating barrel. The extrusion die head is an extrusion die head with multiple branch channels. This is a very mature technology, so it is not repeated in this case. The two rotating shafts include a conveying area, a premixing area, and a fine mixing area from the feed end to the discharge end. The rotating shafts are provided with thread blocks at the positions of the conveying area, the premixing area, and the discharge area. The thread gap of the thread block in the premixing area is smaller than the thread gap of the thread block in the conveying area. A ball socket groove with a diameter of R is provided on the fine mixing area. The ball socket groove arranged on the rotating shaft is staggered by a length of R / 2 with the ball socket groove arranged on the adjacent heating barrel. The thread blocks on the two rotating shafts are meshed with each other, and the ball socket grooves on the two rotating shafts are staggered by a length of R / 2. The rotating shaft is driven by a motor, which is a very mature technology, so it is not repeated in this case.

[0013] The present invention pushes the material forward through the screw block in the conveying area, conveys it to the premixing area for preliminary mixing and melting through the screw block, and then produces three-dimensional flow through the ball socket in the fine mixing area, and is subjected to comprehensive effects such as shearing, peeling, coordination, kneading, etc., so that the material is fully mixed to form an effective barrier network, and then discharged to the extrusion die head through the discharge area for extrusion.

[0014] Preferably, the water cooling mechanism includes an inclined cooling plate, a flushing pipe, and a water collecting trough with an opening on the top. The strip feed inlet of the inclined cooling plate is lower than the strip discharge port of the inclined cooling plate. Baffles are provided on the front and rear sides of the inclined cooling plate. The water collecting trough is provided at the bottom of the strip feed inlet of the inclined cooling plate, and the water outlet of the flushing pipe is located at the strip discharge port of the inclined cooling plate.

[0015] The present invention passes the strip through the inclined cooling plate, and water is poured into the inclined cooling plate through the flushing pipe. The direction of water pouring is opposite to the direction of the strip. The cooling water continuously flushes the surface of the cooled object in a flowing manner, which can continuously take away heat, form a strong convection heat exchange, and accelerate the heat dissipation speed. In immersion cooling, the cooling medium is relatively static and mainly relies on heat conduction to dissipate heat. The cooling efficiency is relatively low, thereby enhancing the cooling efficiency.

[0016] Preferably, a first rotating bearing is provided at the left end of the first air inlet pipe, the right end of the first air inlet pipe is a closed end, and a second rotating bearing is provided at the right end of the rotating shaft. The first rotating bearing and the second rotating bearing are both fixed on the discharge box, and the rotating shaft is fixedly connected to the inner ring of the second rotating bearing, and the first air inlet pipe is fixedly connected to the inner ring of the first rotating bearing. The first air inlet pipe drives the gear to rotate through a motor, thereby driving the first air inlet pipe to rotate. A powder discharge port is provided at the bottom of the discharge box, and the powder discharge port is fixed to the side wall of the heating barrel. The outer ring of the second rotating bearing is connected to the flushing pipe through a pipe, and the outer ring of the first rotating bearing is connected to the steam generator through a pipe. The water outlet of the water collecting tank is connected to the input end of the steam generator. In order to prevent insufficient cooling water, water can also be drawn from the water collecting tank into the flushing pipe for recycling.

[0017] The present invention ensures the rotation of the first air intake pipe and the rotating shaft through the design of the first rotating bearing and the second rotating bearing, while facilitating the connection of other pipelines with the first air intake pipe and the rotating shaft.

[0018] The present invention inputs the heat generated by the steam generator into the spiral blades through the first air inlet pipe, and then the cooled liquid flows into the flushing pipe. After the flushing pipe cools the strip, the liquid after absorbing heat enters the water collection tank and then enters the steam generator, so as to be recycled, save resources, and be more environmentally friendly.

[0019] Preferably, a partition plate is fixedly connected to the inner wall of the water collecting tank, and the partition plate divides the water collecting tank into a water collecting area and a filtration area. The water collecting area is arranged below the strip feed port of the inclined cooling plate.

[0020] Preferably, a water inlet pipe is provided at the top of the water collection area, a water inlet trough is provided at the top of the water inlet pipe, the water inlet trough is provided below the strip feed port of the inclined cooling plate, an overflow port is provided at the upper portion of the partition plate, a filter plate is placed on the filter area, the position of the filter plate is lower than the position of the overflow port, a water outlet connected to the input end of the steam generator is provided at the bottom of the filter area, a cover plate is fixedly connected to the top opening of the filter area, and the water inlet pipe passes through the cover plate and extends to the lower portion of the water collection area.

[0021] In the present invention, water flowing from the inclined cooling plate enters the bottom of the water collection area and then flows to the filter plate through the overflow port. Clean water remains at the bottom of the filter plate, thereby filtering the water to prevent excessive impurities from affecting the service life of the steam generator. At the same time, the water flow sound can be reduced, achieving a certain quiet effect.

[0022] Preferably, the jet mechanism includes a second air inlet pipe, one end of which is fixedly connected to an air pump, and the other end of which is fixedly connected to a spray plate, and the lower surface of the spray plate is fixedly connected to a spray head, through which water on the surface of the strip is removed.

[0023] Preferably, the cutting mechanism includes an extrusion rotating roller, a guide roller, a cutting table, and a cutting rotating roller. The extrusion rotating roller is arranged above the guide roller. The rotation directions of the extrusion rotating roller and the guide roller are opposite, thereby ensuring that the material can be transported forward. The cutting table is arranged on the right side of the guide roller, and the cutting rotating roller is arranged on the right side of the cutting table. The surface of the cutting rotating roller has more than three cutting blades arrayed along the circumferential direction.

[0024] The present invention conveys the strips in advance by squeezing the rotating rollers and the guide rollers, and then cuts the rotating rollers. When the cutting blades rotate to the cutting table, the strips are cut into particles, thus completing the function of continuous particle cutting.

[0025] Preferably, the secondary steam drying mechanism has the same structure as the primary steam drying mechanism, the first air inlet pipe of the secondary steam drying mechanism is also connected to the input end of the steam generator, and the cooled liquid also flows into the flushing pipeline.

[0026] In summary, the beneficial effects of the present invention are: 1. In the present invention, the three materials of POK, EVOH and EAA are compounded in a certain proportion to form a three-phase mixed system, which has a synergistic effect and improves the oxygen barrier effect; the compatibility of POK and EVOH materials is improved by a special compatibilizer for POK, and the mechanical properties of the materials are improved; the oxygen barrier effect of POK is basically not reduced under high temperature and high humidity, and the oxygen barrier effect of the whole system under high temperature and high humidity conditions is improved; the antioxidant system improves the thermal stability of EVOH and POK materials during processing, and solves the problem that the materials are easy to decompose during processing and are easy to yellow after long-term use; 2. The present invention pre-dries hygroscopic materials such as POK, EVOH, and EAA to prevent the raw materials from absorbing moisture or containing water before processing, and to prevent the water from being released during the melting process, which may cause bubbles. If there are bubbles during the melting process, gas or liquid may penetrate through the channels formed by the bubbles, greatly reducing the barrier properties of the material. After that, the materials are mixed evenly to form an effective barrier network, and then cooled and solidified, pelletized, and dried again to remove surface water, thereby obtaining POK and EVOH modified high barrier materials; 3. The present invention conveys the steam generated by the steam generator through the first air inlet pipe to the air outlet pipe into the inner cavity of the spiral blade, thereby heating the spiral blade, so that the material falling into the discharge box is dried while being conveyed, and then conveyed to the twin-screw mixing mechanism. The steam after heat release is cooled into water and discharged into the water outlet cavity through the water outlet hole, and then discharged through the water outlet pipe, thereby drying the material and keeping the material dry; 4. The present invention passes the strip through the inclined cooling plate, and water is poured into the inclined cooling plate through the flushing pipe. The direction of water pouring is opposite to the direction of the strip. The cooling water continuously flushes the surface of the cooled object in a flowing manner, which can continuously take away the heat, form a strong convection heat exchange, and accelerate the heat dissipation speed. In immersion cooling, the cooling medium is relatively static, and heat is mainly dissipated by heat conduction. The cooling efficiency is relatively low, thereby enhancing the cooling efficiency; 5. The present invention inputs the heat generated by the steam generator into the spiral blades through the first air inlet pipe, and then the cooled liquid flows into the flushing pipe. After the flushing pipe cools the strip, the heat-absorbing liquid enters the water collection tank and then enters the steam generator, so as to be recycled, save resources and be more environmentally friendly. 6. The present invention pushes the material forward through the screw block in the conveying area, conveys it to the premixing area for preliminary mixing and melting through the screw block, and then produces three-dimensional flow through the ball socket in the fine mixing area, and is subjected to comprehensive effects such as shearing, peeling, coordination, and kneading, so that the material is fully mixed to form an effective barrier network, and then discharged to the extrusion die head through the discharge area for extrusion. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the process of the twin-screw granulation equipment of the present invention; Figure 2 It is a schematic diagram of the primary steam drying mechanism of the present invention; Figure 3 The present invention Figure 2 An enlarged schematic diagram of point A; Figure 4 It is a cross-sectional schematic diagram of the connection of the rotating shaft, the first air inlet pipe, the spiral blades, and the air outlet pipe of the present invention; Figure 5 is a schematic diagram of the air outlet holes on the rotating shaft of the present invention; Figure 6 It is a cross-sectional schematic diagram of the barrel and a single rotating shaft of the present invention; Figure 7 is a schematic cross-sectional view of two rotating shafts of the present invention; Figure 8 It is a schematic diagram of the water cooling mechanism and the cutting mechanism of the present invention; Fig. 9 is a schematic diagram of a baffle of the present invention; Fig.10 It is a schematic diagram of the jet mechanism of the present invention; Fig.11 It is a schematic diagram of the oxygen barrier synergistic effect of the present invention.

[0028] Description of the drawings: 2. primary steam drying mechanism; 3. twin-screw mixing mechanism; 4. water cooling mechanism; 5. jetting mechanism; 6. cutting mechanism; 7. secondary steam drying mechanism; 21. discharge box; 22. internal hollow rotating shaft; 23. first air inlet pipe; 24. air outlet pipe; 25. spiral blade; 31. heating barrel; 32. rotating shaft; 30. extrusion die; 33. conveying area; 34. premixing area; 35. fine mixing area; 37. discharge area; 36. ball and socket groove; 41. Inclined cooling plate; 42, flushing pipe; 43, water collecting trough; 231, first rotating bearing; 221, second rotating bearing; 631, powder discharge port; 8, steam generator; 430, partition plate; 431, water collecting area; 432, filtering area; 433, water inlet pipe; 434, water inlet trough; 435, overflow port; 436, filter plate; 437, cover plate; 61, extrusion rotating roller; 62, guide roller; 63, cutting table; 64, cutting rotating roller; 65, cutting disc. DETAILED DESCRIPTION

[0029] The following specific embodiments are merely explanations of the present invention and are not limitations of the present invention. After reading this specification, those skilled in the art may make modifications to the embodiments without any creative contribution as needed. However, such modifications are protected by the patent law as long as they are within the scope of the claims of the present invention.

[0030] The present invention will be described in detail below with reference to the accompanying drawings by way of embodiments.

[0031] Example 1

[0032] like Fig.11 As shown, a method for preparing a high barrier material by blending and modifying POK and EVOH comprises the following steps: S1, pre-drying, pre-drying the hygroscopic components of POK, EVOH, EAA, POK special compatibilizer, and antioxidant, such as EVOH and EAA, through the steam drying mechanism of the twin-screw granulating equipment 1, and conveying the condensed water generated after drying to the water cooling mechanism; S2, mixing uniformly, heating and melting POK, EVOH, EAA, POK special compatibilizer, and antioxidant through the twin screw mechanism of the twin screw granulating equipment 1, efficiently mixing and uniformly forming a mixture, and then extruding into strips; S3, cooling and solidification, the strips are cooled and stretched into shape by the water cooling mechanism of the twin-screw granulating equipment 1, and the water after the water cooling mechanism absorbs heat is filtered and transported to the steam generator for use in the steam drying mechanism; S4, jetting to remove water, the strips are jetted through the jetting mechanism of the twin-screw granulating device 1 to remove water droplets on the surface; S5, pelletizing, cutting the strips after removing the surface water droplets into uniform pellets through the cutting mechanism of the twin-screw pelletizing device 1; S6, secondary drying, the particles are secondary dried to remove excess water, thereby obtaining a high barrier raw material.

[0033] The component ratio of the high barrier raw material is POK 42%, EVOH 42%, POK special compatibilizer 10%, EAA 5%, antioxidant 1%. The POK special compatibilizer is a modified material based on POK grafted with maleic anhydride grafts. The antioxidant is a mixture of two or more hindered phenol type antioxidants, thioesters or phosphite antioxidants.

[0034] like Fig.11 As shown, the presence of EVOH makes the path of small gas molecules passing through the material become tortuous and longer, and the gas barrier effect is improved. The presence of EVOH makes small gas molecules need to take a detour to move forward.

[0035] like Figure 1 As shown, the twin-screw granulating equipment 1 includes a primary steam drying mechanism 2, a twin-screw mixing mechanism 3, a water cooling mechanism 4, an air jet mechanism 5, a cutting mechanism 6, and a secondary steam drying mechanism 7 which are arranged in sequence.

[0036] like Figure 3-5As shown, the primary steam drying mechanism 2 includes a discharge box 21 with a top opening, an internally hollow rotating shaft 22, a first air inlet pipe 23, an air outlet pipe 24, and a spiral blade 25. The rotating shaft 22 is arranged in the inner cavity of the discharge box 21, the first air inlet pipe 23 is sleeved and fixed on the inner side of the rotating shaft 22, a water outlet cavity 26 is arranged between the first air inlet pipe 23 and the rotating shaft 22, the left end of the first air inlet pipe 23 protrudes from the left side of the rotating shaft 22, and the right end of the first air inlet pipe 23 is located in the rotating shaft 22. The interior of the spiral blade 25 is hollow, and the spiral blade 25 is arranged on the outer wall of the rotating shaft 22. The air outlet pipe 24 is provided at the position where the spiral blade 25 is provided on the rotating shaft 22. One end of the air outlet pipe 24 is fixedly connected to the first air inlet pipe 23 and is communicated with the inner wall of the first air inlet pipe 23. The other end of the air outlet pipe 24 is fixedly connected to the rotating shaft 22 and is located in the inner cavity of the spiral blade 25. A water outlet hole 20 is also opened at the position where the spiral blade 25 is provided on the rotating shaft 22.

[0037] like Figure 6-7 As shown, the twin-screw mixing mechanism 3 includes a heating barrel 31, two rotating shafts 32 that can rotate in the heating barrel 31, and an extrusion die head 30 arranged at the end of the heating barrel 31. The two rotating shafts 32 include a conveying area 33, a premixing area 34, a fine mixing area 35 and a discharge area 37 in sequence from the feeding end to the discharging end. The rotating shafts 32 are provided with thread blocks at the positions of the conveying area 33, the premixing area 34 and the discharge area 37. The thread gap of the thread block in the premixing area 34 is smaller than the thread gap of the thread block in the conveying area 33. The heating barrel 31 corresponding to the fine mixing area 35 and the rotating shaft 32 are provided with ball sockets 36 with a diameter of R. The ball sockets 36 arranged on the rotating shaft 32 are staggered by a length of R / 2 with the ball sockets 36 arranged on the adjacent heating barrel 31. The thread blocks on the two rotating shafts 32 are meshed with each other, and the ball sockets 36 on the two rotating shafts 32 are staggered by a length of R / 2.

[0038] like Figure 8-9As shown, the water cooling mechanism 4 includes an inclined cooling plate 41, a flushing pipe 42, and a water collecting trough 43 with an opening on the top. The strip feed port of the inclined cooling plate 41 is lower than the strip discharge port of the inclined cooling plate 41. Baffles 40 are provided on the front and rear sides of the inclined cooling plate 41. The water collecting trough 43 is provided at the bottom of the strip feed port of the inclined cooling plate 41. The water outlet of the flushing pipe 42 is located at the strip discharge port of the inclined cooling plate 41. A partition plate 430 is fixedly connected to the inner wall of the water collecting trough 43. The partition plate 430 divides the water collecting trough 43 into a water collecting area 431 and a filtering area 432. The water collecting area 431 is provided at the strip of the inclined cooling plate 41. Below the feed port, a water inlet pipe 433 is provided at the top of the water collection area 431, and a water inlet trough 434 is provided at the top of the water inlet pipe 433. The water inlet trough 434 is provided below the strip feed port of the inclined cooling plate 41, and an overflow port 435 is opened at the upper part of the partition plate 430. A filter plate 436 is placed on the filter area 432, and the position of the filter plate 436 is lower than the position of the overflow port 435. A water outlet 438 connected to the input end of the steam generator 8 is provided at the bottom of the filter area 432, and a cover plate 437 is fixedly connected to the top opening of the filter area 432. The water inlet pipe 433 passes through the cover plate 437 and extends to the lower part of the water collection area 431.

[0039] like Figure 1 As shown, the left end of the first air inlet pipe 23 is provided with a first rotary bearing 231, the right end of the first air inlet pipe 23 is a closed end, the right end of the rotating shaft 22 is provided with a second rotary bearing 221, the first rotary bearing 231 and the second rotary bearing 221 are both fixed on the discharge box 21, the rotating shaft 22 is fixedly connected to the inner ring of the second rotary bearing 221, and the first air inlet pipe 23 is fixedly connected to the inner ring of the first rotary bearing 231. The first air inlet pipe 23 drives the gear to rotate through the motor, thereby driving the air inlet pipe to rotate, the bottom of the discharge box 21 is provided with a powder discharge port 631, and the powder discharge port 631 is fixed to the side wall of the heating barrel 31, the outer ring of the second rotary bearing 221 is connected to the flushing pipe 42 through a pipe, the outer ring of the first rotary bearing 231 is connected to the steam generator 8 through a pipe, and the water outlet 438 of the water collecting tank 43 is connected to the input end of the steam generator 8.

[0040] like Fig.10 As shown, the jet mechanism 5 includes a second air inlet pipe 51 , one end of which is fixedly connected to an air pump 52 , and the other end of which is fixedly connected to a spray plate 53 , and a nozzle 54 is fixedly connected to the lower surface of the spray plate 53 .

[0041] like Figure 8As shown, the cutting mechanism 6 includes an extrusion rotating roller 61, a guide roller 62, a cutting table 63, and a cutting rotating roller 64. The extrusion rotating roller 61 is arranged above the guide roller 62, the cutting table 63 is arranged on the right side of the guide roller 62, and the cutting rotating roller 64 is arranged on the right side of the cutting table 63. The surface of the cutting rotating roller 64 has more than three cutting blades 65 arrayed along the circumferential direction.

[0042] Working principle: Figure 1-10 As shown, when in use, the hygroscopic components of POK, EVOH, EAA, POK special compatibilizer, and antioxidant, such as EVOH and EAA, are transported to the discharge box 21, and the first air inlet pipe 23 transports the steam generated by the steam generator to the air outlet pipe 24 and enters the inner cavity of the spiral blade 25, so as to heat the spiral blade 25, so that the material falling into the discharge box 21 is dried while being transported, and then transported to the twin-screw mixing mechanism. The steam after heat release is cooled into water and discharged into the water outlet cavity 26 through the water outlet hole 20, and then discharged through the water outlet pipe. Other materials are input into the twin-screw mixing mechanism 3 together with the dried EVOH and EA, and the materials are pushed forward by the threaded block of the conveying area 33, and transported to the premixing area 34 for preliminary mixing and melting through the threaded block, and then to the fine mixing area 35 to generate three-dimensional flow through the ball socket, and are sheared, peeled, The combined effects of coordination and kneading make the materials fully mixed to form an effective barrier network, and then the materials are discharged to the extrusion die head through the discharge area 37 for extrusion, and then the strips are drawn. The strips pass through the inclined cooling plate 41, and water is poured into the flushing pipe 42 to cool the strips. Then the water on the surface is removed by the jet mechanism 5. Then the cooled strips are cut into particles by the cutting mechanism 6 to complete the continuous pelletizing effect. The particles are dried for a second time to remove excess water, so as to obtain high barrier raw materials. During the whole process, the first air inlet pipe 23 inputs the steam generated by the steam generator into the spiral blade 25, and then the cooled liquid flows into the flushing pipe 42. After the flushing pipe 42 cools the strips, the liquid after absorbing heat enters the water collecting tank, and then enters the steam generator, so as to be recycled, save resources, and be more environmentally friendly.

[0043] Example 2 Different from Example 1, the component ratios of the high barrier raw materials are POK 40%, EVOH 40%, POK special compatibilizer 10%, EAA 5%, and antioxidant 5%. The POK special compatibilizer is a modified material based on POK grafted with maleic anhydride grafts, and the antioxidant is a mixture of two or more hindered phenol type antioxidants, thioesters or phosphite antioxidants.

[0044] Example 3 Different from Example 1, the component ratios of the high barrier raw materials are POK 45%, EVOH 45%, POK special compatibilizer 5%, EAA 4%, and antioxidant 1%. The POK special compatibilizer is a modified material based on POK grafted with maleic anhydride grafts, and the antioxidant is a mixture of two or more hindered phenol type antioxidants, thioesters or phosphite antioxidants.

[0045] Example 4 Different from Example 1, a method for preparing a high barrier material by blending and modifying POK and EVOH comprises the following steps: S1, mixing uniformly, heating and melting POK, EVOH, EAA, POK special compatibilizer, and antioxidant through the twin screw mechanism of the twin screw granulation equipment 1, efficiently mixing and uniformly forming a mixture, and then extruding into strips; S2, cooling and solidification, the strips are cooled and stretched into shape by the water cooling mechanism of the twin-screw granulating equipment 1, and the water after the water cooling mechanism absorbs heat is filtered and transported to the steam generator for use in the steam drying mechanism; S3, jetting to remove water, the strips are jetted through the jet mechanism of the twin-screw granulating device 1 to remove water droplets on the surface; S4, pelletizing, cutting the strips after removing the surface water droplets into uniform pellets through the cutting mechanism of the twin-screw pelletizing device 1; S5, secondary drying, the particles are secondary dried to remove excess water, thereby obtaining a high barrier raw material.

[0046] Comparative Example 1 S1, mixing uniformly, heating, melting and mixing POK, EVOH, EAA, POK special compatibilizer and antioxidant through a single screw of a single screw granulating equipment to form a mixture, and then extruding it into strips; S2, cooling and solidifying, the strip is drawn and cooled and solidified by soaking; S3, air jet dehydration, the strip is jetted to remove water droplets on the surface; S4, pelletizing, cutting the strips into uniform particles through a cutting mechanism; S5, secondary drying, the particles are secondary dried to remove excess water, thereby obtaining a high barrier raw material.

[0047] According to GB / T 1038-2000: Test method for gas permeability of plastic films and sheets, the oxygen permeability of Example 1, Example 2, Example 3, Example 4, Comparative Document 1 and sample films made of EVOH material were measured in an atmosphere of temperature 80° C. and humidity 65% ​​RH.

[0048]

[0049] It can be seen from the above results that the high barrier raw material obtained by Example 1 of the present invention has the best oxygen barrier effect.

Claims

1. A method for preparing a high barrier material by blending and modifying POK and EVOH, characterized in that: The following steps are involved: S1, pre-drying, pre-drying the hygroscopic components of POK, EVOH, EAA, POK special compatibilizer, and antioxidant through the steam drying mechanism of the twin-screw granulation equipment (1), and conveying the condensed water generated after drying to the water cooling mechanism; S2, mixing uniformly, heating and melting POK, EVOH, EAA, POK special compatibilizer, and antioxidant through the twin screw mechanism of the twin screw granulation equipment (1) and efficiently mixing to form a mixture, and then extruding it into strips; S3, cooling and solidification, cooling and stretching the strips through the water cooling mechanism (4) of the twin-screw granulating equipment (1) to shape the strips, and the water after absorbing heat from the water cooling mechanism (4) is filtered and transported to the steam generator (8) for use in the steam drying mechanism; S4, air jet dehydration, wherein the strips are jetted through the air jet mechanism (5) of the twin-screw granulating device (1) to remove water droplets on the surface; S5, pelletizing, cutting the strips after removing the water droplets on the surface into uniform pellets through the cutting mechanism (6) of the twin-screw pelletizing device (1); S6, secondary drying, the particles are secondary dried to remove excess water, thereby obtaining a high barrier raw material.

2. The method for preparing a high barrier material modified by blending POK and EVOH according to claim 1, characterized in that: The component proportions of the high barrier raw materials are POK 40%-45%, EVOH 40%-45%, POK special compatibilizer 5%-10%, EAA 2%-10%, and antioxidant 1%-5%. The POK special compatibilizer is a modified material based on POK-based resin grafted with maleic anhydride grafts, and the antioxidant is a mixture of two or more hindered phenol-type antioxidants, thioesters or phosphite antioxidants.

3. The method for preparing a high barrier material by blending and modifying POK and EVOH according to claim 1, characterized in that: The twin-screw granulating equipment (1) comprises a primary steam drying mechanism (2), a twin-screw mixing mechanism (3), a water cooling mechanism (4), an air jet mechanism (5), a cutting mechanism (6), and a secondary steam drying mechanism (7) which are arranged in sequence.

4. The method for preparing a high barrier material by blending and modifying POK and EVOH according to claim 3, characterized in that: The primary steam drying mechanism (2) comprises a discharge box (21) with a top opening, a rotating shaft (22) with a hollow interior, a first air inlet pipe (23), an air outlet pipe (24), and a spiral blade (25); the rotating shaft (22) is arranged in the inner cavity of the discharge box (21); the first air inlet pipe (23) is sleeved and fixed on the inner side of the rotating shaft (22); a water outlet cavity (26) is arranged between the first air inlet pipe (23) and the rotating shaft (22); the left end of the first air inlet pipe (23) protrudes from the left side of the rotating shaft (22); and the right end of the first air inlet pipe (23) is located inside the rotating shaft (22). The interior of the spiral blade (25) is hollow. The spiral blade (25) is arranged on the outer wall of the rotating shaft (22). The air outlet pipe (24) is arranged at the position where the spiral blade (25) is arranged on the rotating shaft (22). One end of the air outlet pipe (24) is fixedly connected to the first air inlet pipe (23) and is in communication with the inner wall of the first air inlet pipe (23). The other end of the air outlet pipe (24) is fixedly connected to the rotating shaft (22) and is located in the inner cavity of the spiral blade (25). A water outlet hole (20) is also provided at the position where the spiral blade (25) is arranged on the rotating shaft (22).

5. The method for preparing a high barrier material modified by blending POK and EVOH according to claim 3, characterized in that: The twin-screw mixing mechanism (3) comprises a heating barrel (31), two rotating shafts (32) rotatable in the heating barrel (31), and an extrusion die head (30) arranged at the end of the heating barrel (31), the two rotating shafts (32) respectively comprising a conveying area (33), a premixing area (34), a fine mixing area (35) and a discharge area (37) from the feeding end to the discharge end, the rotating shafts (32) are provided with screw blocks at the positions of the conveying area (33), the premixing area (34) and the discharge area (37), and the premixing area (3 4) has a thread gap smaller than that of the thread gap of the thread block in the conveying zone (33); a ball socket groove (36) with a diameter of R is provided at the heating barrel (31) corresponding to the fine mixing zone (35) and on the rotating shaft (32); the ball socket groove (36) arranged on the rotating shaft (32) is staggered by a length of R / 2 with the ball socket groove (36) arranged on the adjacent heating barrel (31); the thread blocks on the two rotating shafts (32) are meshed with each other, and the ball socket grooves (36) on the two rotating shafts (32) are staggered by a length of R / 2.

6. The method for preparing a high barrier material modified by blending POK and EVOH according to claim 4, characterized in that: The water cooling mechanism (4) comprises an inclined cooling plate (41), a flushing pipe (42), and a water collecting trough (43) with an opening at the top; the strip material inlet of the inclined cooling plate (41) is lower than the strip material outlet of the inclined cooling plate (41); baffles (40) are provided on the front and rear sides of the inclined cooling plate (41); the water collecting trough (43) is provided at the bottom of the strip material inlet of the inclined cooling plate (41); and the water outlet of the flushing pipe (42) is located at the strip material outlet of the inclined cooling plate (41).

7. The method for preparing a high barrier material modified by blending POK and EVOH according to claim 6, characterized in that: A first rotary bearing (231) is provided at the left end of the first air inlet pipe (23), the right end of the first air inlet pipe (23) is a closed end, a second rotary bearing (221) is provided at the right end of the rotary shaft (22), the first rotary bearing (231) and the second rotary bearing (221) are both fixed on the discharge box (21), the rotary shaft (22) is fixedly connected to the inner ring of the second rotary bearing (221), the first air inlet pipe (23) is fixedly connected to the inner ring of the first rotary bearing (231), a powder discharge port (631) is provided at the bottom of the discharge box (21), the powder discharge port (631) is fixed to the side wall of the heating barrel (31), the outer ring of the second rotary bearing (221) is connected to the flushing pipe (42) via a pipe, the outer ring of the first rotary bearing (231) is connected to the steam generator (8) via a pipe, and the water outlet (438) of the water collecting tank (43) is connected to the input end of the steam generator (8).

8. The method for preparing a high barrier material by blending and modifying POK and EVOH according to claim 7, characterized in that: A partition plate (430) is fixedly connected to the inner wall of the water collecting trough (43), and the partition plate (430) divides the water collecting trough (43) into a water collecting area (431) and a filtering area (432). The water collecting area (431) is arranged below the strip material feed port of the inclined cooling plate (41).

9. The method for preparing a high barrier material by blending and modifying POK and EVOH according to claim 8, characterized in that: A water inlet pipe (433) is provided at the top of the water collection area (431), a water inlet trough (434) is provided at the top of the water inlet pipe (433), and the water inlet trough (434) is provided below the strip material feed port of the inclined cooling plate (41); an overflow port (435) is provided at the top of the partition plate (430); a filter plate (436) is placed on the filter area (432), and the position of the filter plate (436) is lower than the position of the overflow port (435); a water outlet (438) connected to the input end of the steam generator (8) is provided at the bottom of the filter area (432); a cover plate (437) is fixedly connected to the top opening of the filter area (432), and the water inlet pipe (433) passes through the cover plate (437) and extends to the lower part of the water collection area (431).

10. The method for preparing a high barrier material modified by blending POK and EVOH according to claim 3, characterized in that: The cutting mechanism (6) comprises an extrusion rotating roller (61), a guide roller (62), a cutting table (63), and a cutting rotating roller (64); the extrusion rotating roller (61) is arranged above the guide roller (62); the cutting table (63) is arranged on the right side of the guide roller (62); the cutting rotating roller (64) is arranged on the right side of the cutting table (63); and the surface of the cutting rotating roller (64) has more than three cutting blades (65) arranged in an array along a circumferential direction.

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