High-transparency modified resin plate one-step-method single-screw extrusion device and manufacturing method

Abstract

The invention discloses a high-transparency modified resin plate one-step-method single-screw extrusion device and a manufacturing method.The high-transparency modified resin plate one-step-method single-screw extrusion device is provided with an inlet end and an outlet end and comprises a screw and a screw sleeve, the screw sleeve is a through tubular object, and the inlet end of the screw is connected with the outlet end of the screw; the screw sleeve is provided with a screw sleeve inlet and a screw sleeve outlet, the screw rod is arranged in the screw sleeve, the screw rod is provided with a screw rod discharging end and a screw rod driving end, the screw rod discharging end is arranged in the screw sleeve outlet, the screw rod driving end is arranged in the screw sleeve inlet, and the screw rod driving end is connected with the screw rod driving device. The screw rod is driven by the screw rod driving device to rotate in the screw sleeve; the one-step single-screw extrusion device for the high-transparency modified resin plate sequentially comprises a feeding section, a feeding section, a compression section, a mixing section, a degassing section and a metering section from the screw driving end direction to the screw discharging end direction, a feeding opening is formed in the feeding section, materials are fed from the feeding opening, and after the materials are rotated by the screw and extruded by the screw sleeve, the materials are extruded by the screw sleeve. And discharging from an outlet of the screw sleeve. According to the invention, the trace powder additive and the high-transparency resin can be directly mixed and added, the high-transparency anti-yellowing plate is extruded and produced by a single-screw extrusion device through a one-step method, the produced product is comprehensive, uniform and consistent, the plasticizing effect is ensured, the generation of fish eyes and crystal points is reduced, the product stability is good, and the production cost is low. The production quality and the production efficiency are high.

Description

Technical Field

[0001] The invention relates to the field of high-transparency resin processing, in particular to a one-step single-screw extruder and a manufacturing method for a high-transparency modified resin sheet. Background Art

[0002] In the existing high-transparency resin processing process, trace powder additives are needed for the following purposes: 1. Modification to improve the heat resistance and light resistance of the material; 2. Improve the processing performance of the product, such as the demoulding performance and antistatic performance of the material after extrusion, hot pressing and other processing procedures. Trace amounts generally refer to the total amount of addition within 1000ppm. The high-transparency resin sheet here refers to an optical resin sheet with a light transmittance of 91.5%.

[0003] In the existing production technology, the current trace addition method mainly adopts the masterbatch method, and the steps are as follows: the first step is to take part of the resin and the powder additive and weigh them separately, mix them, and use a twin-screw extruder to granulate to obtain the masterbatch; the second step is to take the resin and the masterbatch and weigh them separately, mix them, and use a single-screw extruder to extrude and produce the product. The advantage of this masterbatch method is that the process is mature and the product is stable. However, when the resin and the masterbatch are mixed, a part of the resin material is plasticized for the second time, and the material will crack and yellow, affecting the production quality and production efficiency of the product. In addition, the performance loss of additives is large. For example, antioxidants and other additives are decomposed at high temperature for the second time, the efficiency is reduced, the dosage is increased, and many impurities are introduced from the side. There are many steps and processes in the secondary processing, and the risk of foreign matter and impurities in the middle is significantly increased. These points are particularly obvious in the field of optical materials with high requirements for product transparency and color.

[0004] With current production technology, if a direct addition and mixing method is adopted, that is, the resin and powder additives are weighed separately, mixed and directly fed into the extruder, crystal points and fish eyes will be produced. The main reasons for their production are: 1. The mixing of insoluble foreign impurities; 2. Carbides produced by material cracking; 3. Uneven plasticization and crystallization of some materials. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a one-step single-screw extruder and a manufacturing method for a highly transparent modified resin sheet.

[0006] The technical scheme of the present invention is: a one-step single-screw extruder for a highly transparent modified resin sheet, the one-step single-screw extruder for a highly transparent modified resin sheet is provided with an inlet end and an outlet end, the one-step single-screw extruder for a highly transparent modified resin sheet comprises a screw and a sleeve, the sleeve is a through tubular object, provided with a sleeve inlet and a sleeve outlet, the screw is arranged in the sleeve, the screw is provided with a screw discharge end and a screw drive end, the screw discharge end is arranged in the sleeve outlet, the screw drive end is arranged in the sleeve inlet, and the screw drive end is connected to the screw drive device, and the screw is driven by the screw drive device to rotate in the sleeve; the one-step single-screw extruder for a highly transparent modified resin sheet is sequentially divided into a feeding section, a feeding section, a compression section, a mixing section, a degassing section and a metering section from the screw drive end direction to the screw discharge end direction, the feeding section is provided with a feeding port, the material is fed from the feeding port, and after the rotation of the screw and the extrusion of the sleeve, the material is discharged from the sleeve outlet.

[0007] Preferably, the overall length of the feed section of the screw of the one-step single-screw extruder for the highly transparent modified resin sheet is 10 to 13D, and the threads on the screw in this area are threads of equal depth and equal distance.

[0008] Preferably, the feeding section includes a first feeding section, a second feeding section and a third feeding section, which are located in the area of ​​the feeding section and the first feeding section, and a fixed sleeve is provided on the outside of the screw sleeve, wherein, in the feeding section area, the fixed sleeve and the screw sleeve are provided with a feeding port; the temperature control method of the screw sleeve in the feeding section area of ​​the high-transparency modified resin sheet one-step single-screw extruder is a water-cooled structure, the screw sleeve in the first feeding section area adopts a nested structure, including an outer layer and an inner layer, the temperature control method of the outer layer is a heating structure, and the inner layer is a water-cooled structure with an internal rotating flow channel, the surface of the screw sleeve in the second feeding section, the third feeding section, and the compression section area adopts a spiral groove method to embed cooling water pipes for water cooling, the overall sleeve is subjected to a dual cooling method of fan cold air blowing, and the external wrapped heater is used for heating. The temperature control method of the screw sleeve in the mixing section, degassing section and metering section area is surface fan cooling and external heater for temperature control.

[0009] As a further preferred embodiment, in the feeding section area, a feeding section water cooling structure is provided on the fixed sleeve, including a feeding section water cooling inlet and a feeding section water cooling outlet. Cooling water flows in from the feeding section water cooling inlet, flows through the screw sleeve area to cool the screw sleeve, and flows out from the feeding section water cooling outlet. In the first feeding section area, a heating structure and a feeding section water cooling structure are provided. The heating structure is an inner sleeve heating device arranged between the fixed sleeve and the screw sleeve. The inner sleeve heating device heats the screw sleeve. The feeding section water cooling structure includes a feeding section water cooling inlet. and a water-cooled outlet for the feed section, the surface of the screw located in the first feed section, the second feed section, the third feed section and the compression section is provided with a spirally arranged copper tube, the cooling water flows in from the water-cooled inlet of the feed section, passes through the copper tube on the screw sleeve to cool the screw sleeves in the first feed section, the second feed section, the third feed section and the compression section, and flows out from the water-cooled outlet of the feed section; the outside of the screw sleeve located in the second feed section, the third feed section, the compression section, the mixing section, the degassing section and the metering section is provided with a fan to blow air to cool the screw sleeve part.

[0010] Preferably, the compression section of the screw is a structure with a gradually changing groove depth, and the volume ratio from the beginning to the end of the compression section is 2.6 to 3.0; the length is 4 to 6D.

[0011] Preferably, a mixing structure is provided on the screw in the mixing section area, and the mixing structure includes mixing grooves obliquely arranged along the surface of the screw, and the mixing grooves include a feed mixing groove and a discharge mixing groove, and the feed mixing groove and the discharge mixing groove are arranged at intervals from each other; one end of the feed mixing groove close to the inlet end is connected to the compression section, and one end of the feed mixing groove close to the outlet end is closed, and as the screw rotates, the material enters the feed mixing groove from the compression section and cannot continue to enter the degassing section from the feed mixing groove; one end of the discharge mixing groove close to the outlet end is connected to the compression section The degassing section is connected, and one end of the discharge mixing tank close to the inlet end is closed. As the screw rotates, the material cannot enter the discharge mixing tank from the compression section, but the material can enter the degassing section from the discharge mixing tank; a spacing ridge is arranged between the feed mixing tank and the discharge mixing tank, and the spacing ridge includes a high ridge and a low ridge, the top of the high ridge is in contact with the screw sleeve, and the material cannot climb over the high ridge from the feed mixing tank to enter the discharge mixing tank, and a gap is left between the top of the low ridge and the screw sleeve, and the material enters the discharge mixing tank from the feed mixing tank through the gap.

[0012] As a further preference, the low ridge and the high ridge are arranged at intervals, and the inclination direction of the mixing groove is consistent with the rotation direction of the thread on the screw.

[0013] Preferably, the overall length of the mixing section of the one-step single-screw extruder for the highly transparent modified resin sheet is 2D; and the inclination angle between the mixing tank and the axis is between 10 and 30°.

[0014] Preferably, in the degassing section, the screw sleeve is provided with an exhaust port, the exhaust port is connected to a vacuum pumping device, and the vacuum pumping device is used to degas the material in the degassing section.

[0015] As a further preferred embodiment, in the degassing section, the threads on the screw adopt a double thread structure, and the pitch adopts a gradual pitch, changing from 1.5D to 1.0; the thread depth on the screw is deeper than the thread depth on the screw in other areas, and the volume ratio with the metering section (10) is 3.5 to 5.0.

[0016] A one-step single-screw extrusion method for producing a highly transparent modified resin sheet adopts a one-step single-screw extruder for producing a highly transparent modified resin sheet. The method comprises the following steps:

[0017] A. Materials are fed from the feeding port and cooled by the water cooling structure of the feeding section;

[0018] B. As the screw rotates, the material enters the first feeding section. In this area, a heating structure and a water-cooling structure of the feeding section are used to precisely control the temperature. The first feeding section is used to preheat the material at high temperature.

[0019] C. As the screw rotates, the material enters the second feeding section and the third feeding section in turn. The second feeding section and the third feeding section adopt a temperature control method combining an air cooling structure and a water cooling structure. The material in this section is melted and compressed;

[0020] D. As the screw rotates, the material enters the compression section, where the shear heat is discharged in a timely manner;

[0021] E. As the screw rotates, the material enters the mixing section, and the mixing structure performs mixing. In the mixing structure, the material enters the feed mixing tank from the compression section. The end of the feed mixing tank close to the outlet is closed, and the material cannot enter the degassing section. As the screw rotates, the material overflows from the feed mixing tank to the discharge mixing tank;

[0022] F. As the screw rotates, the material enters the degassing section from the end of the discharging mixing tank close to the outlet, and the vacuum device degasses the material from the exhaust port;

[0023] G. Finally, the material passes through the metering section, which calculates the discharge quantity and discharges the finished product from the outlet.

[0024] As further preferred:

[0025] In step B, the temperature condition is controlled at Tg+(80-100)°C;

[0026] In step C, the temperature condition of the second feeding section (62) is controlled at Tg+(0-10)°C, and the temperature condition of the third feeding section (63) is controlled at Tg+(10-30)°C;

[0027] In step D, the temperature condition of the compression section (7) is controlled at Tg+(30-50)°C;

[0028] In step E, the temperature condition of the mixing section (8) is controlled at Tg+(60-80)°C;

[0029] In step F, the temperature condition of the degassing section (9) is controlled at Tg+(60-80)°C;

[0030] In step G, the temperature condition of the metering section (10) is controlled at Tg+(60-80)°C.

[0031] The beneficial effects of the present invention are as follows: the present invention adopts a one-step single-screw extruder for production of high-transparency modified resin sheets, which can achieve direct mixing and adding of trace powder additives with high-transparency resins, and directly performs one-time extrusion production through a single-screw extruder. The products produced are fully uniform, the plasticizing effect is guaranteed, the generation of fish eyes and crystal points is reduced, the product has good stability, and the production quality and production efficiency are high.

[0032] The feeding section of the present invention is long and divided into zones, the screw sleeve is used for precise zone temperature control, the resin raw material and powder are preheated at high temperature to ensure that the powder is evenly attached to the surface of the resin particles, and the powder is cooled into a homogeneous quantitative extrusion and conveying to ensure the consistency and stability of the resin feeding.

[0033] The mixing structure of the mixing zone of the present invention changes the flow direction and overflow mode of the fluid, and realizes the flow-stopping mixing structure of the twin-screw structure with a single-screw structure, thereby increasing the uniformity of the material and the mixing effect. In addition, a high pressure difference is formed before and after, which facilitates the removal of some low-molecular, moisture, monomer and other gases in the subsequent degassing section, thereby ensuring product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the present invention.

[0035] Figure 2 It is a structural schematic diagram of the screw of the present invention.

[0036] Figure 3 It is a cross-sectional view of the screw sleeve at the CC position of the present invention.

[0037] Figure 4 It is a schematic structural diagram of the mixing structure of the present invention being planarly unfolded along the surface of the screw.

[0038] Figure 5 It is a cross-sectional view of the kneading structure of the present invention.

[0039] Figure 6 It is a schematic diagram of the material weighing structure of the present invention.

[0040] Figure 7 It is a diagram of the processing temperature setting intervals of each temperature control zone of the present invention (unit: ° C).

[0041] Description of labels:

[0042] 1: outlet end; 2: inlet end; 3: screw sleeve; 4: screw; 5: feeding section; 6: feeding section; 7: compression section; 8: mixing section; 9: degassing section; 10: metering section; 11: heating structure; 12: fixed sleeve; 13: heater; 14: automatic weighing device; 15: mixing device;

[0043] 31: Screw sleeve outlet; 32: Exhaust port; 33: Copper tube; 34: Feeding port; 35: Screw sleeve inlet; 36: Feeding section water cooling inlet; 37: Feeding section water cooling outlet; 38: Feeding section water cooling inlet; 39: Feeding section water cooling outlet;

[0044] 41: screw discharge end; 42: mixing structure; 43: screw drive end; 44: discharge mixing tank; 441: the end of the discharge mixing tank close to the outlet end; 442: the end of the discharge mixing tank close to the inlet end; 45: feed mixing tank; 451: the end of the feed mixing tank close to the outlet end; 452: the end of the feed mixing tank close to the inlet end; 46: interval ridge; 461: high ridge; 462: low ridge; 47: gap;

[0045] 61: first feeding section; 62: second feeding section; 63: third feeding section. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0047] like Figure 1-5As shown, the one-step single screw extruder of the highly transparent modified resin sheet of the present invention is provided with an inlet end 2 and an outlet end 1, and the one-step single screw extruder of the highly transparent modified resin sheet comprises a screw 4 and a screw sleeve 3, wherein the screw sleeve 3 is a through tubular object, and is provided with a screw sleeve inlet 35 and a screw sleeve outlet 31, wherein the screw 4 is arranged in the screw sleeve 3, and the screw 4 is provided with a screw discharge end 41 and a screw drive end 43, wherein the screw discharge end 41 is arranged in the screw sleeve outlet 31, and the screw drive end 43 is arranged in the screw sleeve inlet 35, and The screw driving end 43 is connected to the screw driving device, and the screw driving device drives the screw 4 to rotate in the screw sleeve 3; the high-transparency modified resin sheet one-step single-screw extruder is composed of a feeding section 5, a feeding section 6, a compression section 7, a mixing section 8, a degassing section 9 and a metering section 10 from the direction of the screw driving end 43 to the direction of the screw discharge end 41. The feeding section 5 is provided with a feeding port 34, and the material is fed from the feeding port 34. After the rotation of the screw 4 and the extrusion of the screw sleeve 3, the material is discharged from the screw sleeve outlet 31.

[0048] In this embodiment, the overall length of the feed section 6 of the screw 4 of the one-step single-screw extruder for the high-transparency modified resin sheet is 10 to 13D, D is the diameter of the screw 4, 10D is the ratio of the length of the screw 4 to the diameter of the screw 4 is 10, and the threads on the screw 4 in this area are equal-depth and equidistant threads.

[0049] In this embodiment, the feed section 6 includes a first feed section 61, a second feed section 62 and a third feed section 63, which are located in the area of ​​the feeding section 5 and the first feeding section 61. The outside of the screw sleeve 3 is provided with a fixed sleeve 12, wherein, in the feeding section 5 area, the fixed sleeve 12 and the screw sleeve 3 are provided with a feeding port 34; the temperature control method of the screw sleeve 3 in the feeding section 5 area of ​​the high-transparency modified resin sheet one-step single-screw extruder is a water-cooled structure, and the screw sleeve 3 in the first feeding section 61 area adopts a nested structure, including an outer layer and an inner layer, and the temperature control method of the outer layer is The heating structure 11 has an inner layer which is a water-cooling structure with an internally designed rotating flow channel. The surface of the screw sleeve 3 in the second feed section 62, the third feed section 63, and the compression section 7 area is water-cooled by an embedded cooling water pipe in a spiral groove manner. The overall sleeve adopts a dual cooling method of fan cold air blowing, and an externally wrapped heater 13 is used for heating. The temperature control method ensures timely removal of plasticizing heat, and the temperature control knife is accurately controlled at ±0.5°C. The temperature control method of the screw sleeve 3 in the mixing section 8, the degassing section 9 and the metering section 10 is surface fan cooling and temperature control by an external heater 13.

[0050] Compared with the structure of the existing single-screw extruder, the existing feed section 6 is only 3-5D longer and is only an integral section. After the feed section is the compression section, which is short and not segmented. The overall length of the feed section 6 adopted by the present invention becomes longer, which is convenient for multiple partitions to realize their respective functions. The feed section 6 is divided into the first feed section 61, the second feed section 62, and the third feed section 63. The compression section 7 is followed by the third feed section 63. The purpose of multiple partitions is that the first feed section 61 is used for high-temperature preheating of raw materials and powders to ensure that the micropowder is evenly attached to the surface of the resin particles. The second feed section 62 and the third feed section 63 are used for low-temperature cooling of materials to form a homogeneous phase, which can completely and evenly distribute the resin particles with micropowder to restore the solid state, form quantitative transportation, and uniformly extrude, and the pressure gradient changes evenly to ensure the consistency and stability of the resin feed. Low temperature can make the material more dense. If it is still high temperature, the added powder will melt and slip.

[0051] In this embodiment, in the area of ​​the feeding section 5, the fixed sleeve 12 is provided with a feeding section 5 water cooling structure, including a feeding section water cooling inlet 36 and a feeding section water cooling outlet 37, cooling water flows in from the feeding section water cooling inlet 36, flows through the screw sleeve 3 area to cool the screw sleeve 3, and flows out from the feeding section water cooling outlet 37; in the area of ​​the first feeding section 61, a heating structure 11 and a feeding section water cooling structure are provided, the heating structure 11 is an inner sleeve heating device arranged between the fixed sleeve 12 and the screw sleeve 3, the inner sleeve heating device heats the screw sleeve 3, the feeding section water cooling structure includes a feeding section water cooling inlet 38 and a feeding section water cooling outlet 39. The surface of the screw 4 is provided with a spirally arranged copper tube 33 in the area located in the first feed section 61, the second feed section 62, the third feed section 63 and the compression section 7. Cooling water flows in from the feed section water cooling inlet 38, passes through the copper tube 33 on the screw sleeve 3, and cools the screw sleeve 3 in the first feed section 61, the second feed section 62, the third feed section 63 and the compression section 7 area, and flows out from the feed section water cooling outlet 39; the outside of the screw sleeve 3 located in the second feed section 62, the third feed section 63, the compression section 7, the mixing section 8, the degassing section 9 and the metering section 10 is provided with a fan to blow air to cool part of the screw sleeve 3. In the temperature control method, a water cooling structure is used in areas with high temperature requirements, or a water cooling and air cooling structure are combined, such as the feeding section 5, the feeding section 6 and the compression section 7. Other areas do not have such strict temperature requirements, so an air cooling structure can be used. The water cooling structure has a good temperature control effect, high equipment installation requirements, and high production equipment cost. The air cooling structure has a relatively low temperature control accuracy, but the production equipment structure is simple and can be achieved by using a fan, so the production equipment cost is low.

[0052] In this embodiment, the compression section 7 of the screw 4 is a structure with gradually changing groove depth. From the beginning to the end of the compression section 7, the volume ratio is 2.6 to 3.0; and the length is 4 to 6D.

[0053] like Figure 4-5 As shown, in this embodiment, a mixing structure 42 is provided on the screw 4 in the mixing section 8 area, and the mixing structure 42 includes mixing grooves obliquely arranged along the surface of the screw 4, and the mixing grooves include a feed mixing groove 45 and a discharge mixing groove 44, and the feed mixing groove 45 and the discharge mixing groove 44 are arranged at intervals from each other; an end 452 of the feed mixing groove close to the inlet end is connected to the compression section 7, and an end 451 of the feed mixing groove close to the outlet end is closed. As the screw 4 rotates, the material enters the feed mixing groove 45 from the compression section 7 and cannot continue to enter the degassing section 9 from the feed mixing groove 45; an end 441 of the discharge mixing groove close to the outlet end is connected to the degassing section 9 , one end 442 of the discharge mixing tank near the inlet end is closed. As the screw 4 rotates, the material cannot enter the discharge mixing tank 44 from the compression section 7, but the material can enter the degassing section 9 from the discharge mixing tank 44; a spacing ridge 46 is provided between the feed mixing tank 45 and the discharge mixing tank 44, and the spacing ridge 46 includes a high ridge 461 and a low ridge 462. The top of the high ridge 461 fits with the screw sleeve 3, and the material cannot climb over the high ridge 461 from the feed mixing tank 45 to enter the discharge mixing tank 44. A gap 47 is left between the top of the low ridge 462 and the screw sleeve 3, and the material enters the discharge mixing tank 44 from the feed mixing tank 45 through the gap 47.

[0054] In this embodiment, the low ridge 462 and the high ridge 461 are arranged at intervals, and the inclination direction of the mixing groove is consistent with the thread rotation direction of the screw 4. The overall length of the mixing section 8 is 2D; the inclination angle of the mixing groove to the axis is between 10 and 30 degrees, and 15 to 25 degrees is most suitable.

[0055] The mixing structure 42 of the mixing section 8 allows the trace powder additive to be evenly dispersed, and the uniform performance of the material is guaranteed, which is mainly reflected in: 1. The flow direction of the material fluid is changed. Its unique overflow structure of the mixing tank allows the single-screw extruder to achieve a flow-stopping mixing effect equivalent to that of the twin-screw structure. The deep and shallow structure of the interval 46 and the axial movement of the fluid enhance the uniformity and mixing effect of the material. In addition, a high pressure difference is formed before and after, which facilitates the escape of some low-molecular, moisture, monomer and other gases in the subsequent degassing section 9, thereby ensuring product quality.

[0056] like Figure 3 As shown, in this embodiment, in the degassing section 9, the screw sleeve 3 is provided with an exhaust port 32, and the exhaust port 32 is connected to a vacuum pumping device, and the vacuum pumping device is used to degas the material in the degassing section 9.

[0057] In this embodiment, in the degassing section 9, the thread on the screw 4 adopts a double thread structure, and the pitch adopts a gradual pitch, which changes from 1.5D to 1.0, so as to achieve a better degassing effect and ensure that the resin does not overflow; the thread depth on the screw 4 is deeper than the thread depth on the screw 4 in other areas, and the volume ratio with the metering section 10 is 3.5-5.0, and 4.0-4.5 is the best. The design of this structure is to avoid the situation where the vacuum suction force is too large and the material is sucked out from the exhaust port 32 while the gas in the material is extracted in the degassing section 9.

[0058] The present invention discloses a one-step single-screw extrusion method for producing a highly transparent modified resin sheet, which adopts a one-step single-screw extruder for producing a highly transparent modified resin sheet. The method comprises the following steps:

[0059] A. Materials (such as Figure 6 As shown, the resin and additive are weighed by their own automatic weighing devices 14 and enter the mixing device 15 for uniform mixing) and then fed from the feeding port 34. The raw materials are automatically weighed by a loss-in-weight scale with a ratio setting. The trace powder is added by a high-precision continuous weighing device with an accuracy of 0.1g. The transparent resin raw material is also continuously weighed by a loss-in-weight scale, and after being weighed according to the ratio, it enters the continuous mixing device for mixing and then enters the extrusion device; the feeding section is cooled by a water-cooling structure to prevent the material from agglomerating in this area, which affects the uniformity of the feed, mainly due to the uneven density of the material and the inconsistent particle size, which leads to the difference in friction resistance; the temperature at the feeding point is controlled below Tg;

[0060] B. As the screw 4 rotates, the material enters the first feeding section 61. In this area, the heating structure 11 and the water-cooling structure of the feeding section are used to precisely control the temperature, and the temperature condition is controlled at Tg+(80-100)°C. Tg is the physical property parameter of the raw material, that is, its glass transition temperature, which is about (100-120)°C. The first feeding section 61 is used to preheat the material at high temperature. Additives and resins with different melting points can be fully mixed to form a homogeneous substance in a macroscopic state, ensuring that the resin enters the lower mixing section to form a microscopic homogeneous substance. The consistency and uniformity of the material feeding are guaranteed;

[0061] C. As the screw 4 rotates, the material enters the second feed section 62 and the third feed section 63 in sequence. The second feed section 62 and the third feed section 63 adopt a temperature control method combining an air cooling structure and a water cooling structure. The temperature condition of the second feed section 62 is controlled at Tg+(0-10)°C, and the temperature condition of the third feed section 63 is controlled at Tg+(10-30)°C. The material in this section is melted and compressed, and is in a phase change zone. The shear heat of the material is very large, ensuring that the shear heat is discharged in time;

[0062] D. As the screw 4 rotates, the material enters the compression section 7. The temperature condition of the compression section 7 is controlled at Tg+(30-50)°C. The shear heat is discharged in time in this section, which reduces the possibility of resin cracking and minimizes the microphase inhomogeneity caused by the difference in melting points between the powder material and the resin.

[0063] E. As the screw 4 rotates, the material enters the mixing section 8 and is mixed by a special mixing structure 42. The temperature condition of the mixing section 8 is controlled at Tg+(60-80)°C, which is a lower mixing temperature than the single-phase mixing temperature. This ensures that the material is mixed in a higher viscosity melt state, and it is easier for the material to achieve overall uniformity and consistency, thereby ensuring the plasticizing effect. In the mixing structure 42, the material enters the feed mixing tank 45 from the compression section 7. One end 451 of the feed mixing tank close to the outlet end is closed, and the material cannot enter the degassing section 9. As the screw 4 rotates, the material overflows from the feed mixing tank 45 into the discharge mixing tank 44;

[0064] F. As the screw 4 rotates, the material enters the degassing section 9 from the end 441 of the discharging mixing tank close to the outlet end, and the material is degassed from the exhaust port 32 by the vacuum device. The temperature condition of the degassing section 9 is controlled at Tg+(60-80)°C;

[0065] G. Finally, the material passes through the metering section 10, the metering section 10 calculates the discharge amount, and the finished product is discharged from the outlet 1. The temperature condition of the metering section is controlled at Tg+(60-80)°C. When the material is discharged from the outlet after the metering section, it is already in a molten liquid state.

[0066] The following table is a comparison table of different temperature conditions under the existing conventional process and the process conditions of the present invention (unit: ° C):

[0067]

[0068] The single component in the table is the process condition of the non-modified material. The modification in the highly transparent modified resin sheet described in this application refers to the change of the anti-yellowing performance of the original highly transparent resin sheet.

[0069] In the description of the specification of the present invention, it is necessary to understand that the orientation or positional relationship indicated by the terms "inlet end", "outlet end", "one end", "the other end", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A one-step single screw extruder for highly transparent modified resin sheets, characterized in that The one-step single screw extruder for a highly transparent modified resin sheet is provided with an inlet end (2) and an outlet end (1), and comprises a screw (4) and a screw sleeve (3), wherein the screw sleeve (3) is a through tubular object and is provided with a screw sleeve inlet (35) and a screw sleeve outlet (31), wherein the screw (4) is arranged in the screw sleeve (3), and the screw (4) is provided with a screw discharge end (41) and a screw drive end (43), wherein the screw discharge end (41) is arranged in the screw sleeve outlet (31), and the screw drive end (43) is arranged in the screw sleeve inlet (35), and the screw drive end (43) is arranged in the screw sleeve inlet (35). The moving end (43) is connected to a screw (4) driving device, and the screw (4) is driven by the screw driving device to rotate in the screw sleeve (3); the high-transparency modified resin sheet one-step single-screw extruder comprises a feeding section (5), a feeding section (6), a compression section (7), a mixing section (8), a degassing section (9) and a metering section (10) in sequence from the screw driving end (43) to the screw discharge end (41); the feeding section (5) is provided with a feeding port (34), and the material is fed in from the feeding port (34), and after the rotation of the screw (4) and the extrusion of the screw sleeve (3), the material is discharged from the screw sleeve outlet (31).

2. A one-step single screw extruder for highly transparent modified resin sheets according to claim 1, characterized in that The overall length of the feed section (6) of the screw (4) of the one-step single-screw extruder for the highly transparent modified resin sheet is 10 to 13D, and the threads on the screw (4) in this area are threads of equal depth and equal distance.

3. A one-step single screw extruder for highly transparent modified resin sheets according to claim 1, characterized in that The feeding section (6) comprises a first feeding section (61), a second feeding section (62) and a third feeding section (63), which are located in the area of ​​the feeding section (5) and the first feeding section (61); a fixing sleeve (12) is provided on the outside of the screw sleeve (3); in the area of ​​the feeding section (5), the fixing sleeve (12) and the screw sleeve (3) are provided with a feeding port (34); the temperature control method of the screw sleeve (3) in the area of ​​the feeding section (5) of the one-step single-screw extruder of a high-transparency modified resin sheet is a water-cooling structure, and the screw sleeve (3) in the area of ​​the first feeding section (61) adopts a nested structure, including The outer layer and the inner layer are temperature-controlled by a heating structure (11), and the inner layer is a water-cooled structure with an internally designed rotating flow channel. The surface of the screw sleeve (3) in the second feeding section (62), the third feeding section (63), and the compression section (7) is water-cooled by an embedded cooling water pipe in a spiral groove manner, and the entire sleeve is cooled by a double cooling method of blower cold air. The temperature control method is heating by an externally wrapped heater (13). The temperature control method of the screw sleeve (3) in the mixing section (8), the degassing section (9), and the metering section (10) is surface fan cooling and temperature control by an external heater (13).

4. A one-step single screw extruder for highly transparent modified resin sheets according to claim 3, characterized in that In the feeding section (5) region, a feeding section water cooling structure is provided on the fixed sleeve (12), including a feeding section water cooling inlet (36) and a feeding section water cooling outlet (37). Cooling water flows in from the feeding section water cooling inlet (36), flows through the screw sleeve (3) region to cool the screw sleeve (3), and flows out from the feeding section water cooling outlet (37); in the first feeding section (61) region, a heating structure (11) and a feeding section water cooling structure are provided. The heating structure (11) is an inner sleeve heating device provided between the fixed sleeve (12) and the screw sleeve (3). The inner sleeve heating device heats the screw sleeve (3). The feeding section water cooling structure includes a feeding section water cooling inlet (38) and a feeding section water cooling outlet (39). The screw (4) A spirally arranged copper tube (33) is provided on the surface of the area located in the first feed section (61), the second feed section (62), the third feed section (63) and the compression section (7); cooling water flows in from the feed section water cooling inlet (38), passes through the copper tube (33) on the screw sleeve (3), and cools the screw sleeve (3) in the first feed section (61), the second feed section (62), the third feed section (63) and the compression section (7) area, and flows out from the feed section water cooling outlet (39); a fan is provided outside the screw sleeve (3) located in the second feed section (62), the third feed section (63), the compression section (7), the mixing section (8), the degassing section (9) and the metering section (10) to blow air to cool the screw sleeve (3) part.

5. A one-step single screw extruder for highly transparent modified resin sheet according to claim 1, characterized in that The compression section (7) of the screw (4) is a structure with a gradually changing screw groove depth. The compression section (7) has a volume ratio of 2.6 to 3.0 from the beginning to the end and a length of 4 to 6D.

6. A one-step single screw extruder for highly transparent modified resin sheet according to claim 1, characterized in that The screw (4) in the mixing section (8) region is provided with a mixing structure (42), the mixing structure (42) comprising mixing grooves obliquely arranged along the surface of the screw (4), the mixing grooves comprising a feed mixing groove (45) and a discharge mixing groove (44), the feed mixing groove (45) and the discharge mixing groove (44) being arranged at intervals from each other; one end (452) of the feed mixing groove close to the inlet end is connected to the compression section (7), and one end (451) of the feed mixing groove close to the outlet end is closed, and as the screw (4) rotates, the material enters the feed mixing groove (45) from the compression section (7), and cannot continue to enter the degassing section (9) from the feed mixing groove (45); one end (441) of the discharge mixing groove close to the outlet end is connected to the degassing section (9), and one end (442) of the discharge mixing groove close to the inlet end is closed, and as the screw (4) rotates, The material cannot enter the discharge mixing trough (44) from the compression section (7), but the material can enter the degassing section (9) from the discharge mixing trough (44); a spacing ridge (46) is provided between the feed mixing trough (45) and the discharge mixing trough (44), and the spacing ridge (46) includes a high ridge (461) and a low ridge (462); the top of the high ridge (461) is in contact with the screw sleeve (3), so that the material cannot climb over the high ridge (461) from the feed mixing trough (45) to enter the discharge mixing trough (44); a gap (47) is left between the top of the low ridge (462) and the screw sleeve (3), and the material enters the discharge mixing trough (44) from the feed mixing trough (45) through the gap (47); the low ridge (462) and the high ridge (461) are arranged at a distance, and the inclination direction of the mixing trough is consistent with the direction of rotation of the screw thread on the screw rod (4).

7. The one-step single screw extruder for highly transparent modified resin sheet according to claim 1, characterized in that The overall length of the mixing section (8) of the one-step single-screw extruder for high-transparency modified resin sheets is 2D.

8. The one-step single-screw extruder for highly transparent modified resin sheet according to claim 1, characterized in that In the degassing section (9), the screw sleeve (3) is provided with an exhaust port (32), and the exhaust port (32) is connected to a vacuum pumping device, and the vacuum pumping device is used to degas the material in the degassing section (9); in the degassing section (9), the thread on the screw (4) adopts a double thread structure, and the pitch adopts a gradual pitch, which changes from 1.5D to 1.0; the thread depth on the screw (4) is deeper than the thread depth on the screw (4) in other areas, and the volume ratio with the metering section (10) is 3.5-5.

0.

9. A one-step single screw extrusion method for producing a highly transparent modified resin sheet, characterized in that The method adopts a one-step single-screw extruder for a highly transparent modified resin sheet as claimed in any one of claims 1 to 9, and the method comprises the following steps: A. Materials are fed from the feeding port (34) and simply cooled by the water cooling structure of the feeding section; B. As the screw (4) rotates, the material enters the first feeding section (61). In this area, a heating structure (11) and a water-cooling structure of the feeding section are used to precisely control the temperature. The first feeding section (61) is used to preheat the material at high temperature; C. As the screw (4) rotates, the material enters the second feeding section (62) and the third feeding section (63) in sequence. The second feeding section (62) and the third feeding section (63) adopt a temperature control method combining an air cooling structure and a water cooling structure, and the material in this section is melted and compressed; D. As the screw (4) rotates, the material enters the compression section (7), where the shear heat is discharged in a timely manner; E. As the screw (4) rotates, the material enters the mixing section (8), and the mixing structure (42) performs mixing. In the mixing structure (42), the material enters the feed mixing tank (45) from the compression section (7). One end (451) of the feed mixing tank close to the outlet is closed, so the material cannot enter the degassing section (9). As the screw (4) rotates, the material overflows from the feed mixing tank (45) into the discharge mixing tank (44); F. As the screw (4) rotates, the material enters the degassing section (9) from the end (44) of the discharging mixing tank close to the outlet end, and the material is degassed from the exhaust port (32) by the vacuum device; G. Finally, the material passes through the metering section (10), the metering section (10) calculates the discharge amount, and the finished product is discharged from the outlet (1).

10. The one-step single-screw extrusion method for producing a highly transparent modified resin sheet according to claim 9, characterized in that: In step B, the temperature condition is controlled at Tg+(80-100)°C; In step C, the temperature condition of the second feeding section (62) is controlled at Tg+(0-10)°C, and the temperature condition of the third feeding section (63) is controlled at Tg+(10-30)°C; In step D, the temperature condition of the compression section (7) is controlled at Tg+(30-50)°C; In step E, the temperature condition of the mixing section (8) is controlled at Tg+(60-80)°C; In step F, the temperature condition of the degassing section (9) is controlled at Tg+(40-60)°C; In step G, the temperature condition of the metering section (10) is controlled at Tg+(60-80)°C.

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