CN117301590B - Production process of regenerated environment-friendly polyester film and regenerated PETG heat-shrinkable film - Google Patents
Production process of regenerated environment-friendly polyester film and regenerated PETG heat-shrinkable film Download PDFInfo
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- CN117301590B CN117301590B CN202311625452.4A CN202311625452A CN117301590B CN 117301590 B CN117301590 B CN 117301590B CN 202311625452 A CN202311625452 A CN 202311625452A CN 117301590 B CN117301590 B CN 117301590B
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- 229920005644 polyethylene terephthalate glycol copolymer Polymers 0.000 title claims abstract description 101
- 229920006257 Heat-shrinkable film Polymers 0.000 title claims abstract description 51
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 44
- 229920006267 polyester film Polymers 0.000 title claims abstract description 33
- 239000000463 material Substances 0.000 claims abstract description 140
- 238000001514 detection method Methods 0.000 claims abstract description 57
- 238000000034 method Methods 0.000 claims abstract description 33
- 230000008569 process Effects 0.000 claims abstract description 28
- 239000004970 Chain extender Substances 0.000 claims abstract description 15
- 239000002131 composite material Substances 0.000 claims abstract description 8
- 230000032683 aging Effects 0.000 claims abstract description 4
- 238000007599 discharging Methods 0.000 claims description 48
- 230000003712 anti-aging effect Effects 0.000 claims description 34
- 238000001125 extrusion Methods 0.000 claims description 33
- 238000007493 shaping process Methods 0.000 claims description 32
- 238000001914 filtration Methods 0.000 claims description 30
- 238000002156 mixing Methods 0.000 claims description 28
- 239000006247 magnetic powder Substances 0.000 claims description 24
- 238000009966 trimming Methods 0.000 claims description 24
- 238000005469 granulation Methods 0.000 claims description 20
- 230000003179 granulation Effects 0.000 claims description 20
- 239000002699 waste material Substances 0.000 claims description 12
- 238000004804 winding Methods 0.000 claims description 12
- 239000003795 chemical substances by application Substances 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 10
- 238000005520 cutting process Methods 0.000 claims description 9
- 238000004364 calculation method Methods 0.000 claims description 7
- 239000008187 granular material Substances 0.000 claims description 7
- 229920006300 shrink film Polymers 0.000 claims description 7
- 230000008859 change Effects 0.000 claims description 5
- 239000000155 melt Substances 0.000 claims description 5
- 238000005096 rolling process Methods 0.000 claims description 5
- 238000010345 tape casting Methods 0.000 claims description 5
- 230000009471 action Effects 0.000 claims description 2
- 230000007613 environmental effect Effects 0.000 claims 2
- 238000005453 pelletization Methods 0.000 claims 2
- 230000004927 fusion Effects 0.000 claims 1
- 229920000728 polyester Polymers 0.000 abstract description 47
- 238000004064 recycling Methods 0.000 abstract description 5
- 229920006280 packaging film Polymers 0.000 abstract description 3
- 239000012785 packaging film Substances 0.000 abstract description 3
- 238000007639 printing Methods 0.000 abstract description 3
- 230000008901 benefit Effects 0.000 abstract description 2
- 230000000694 effects Effects 0.000 abstract description 2
- 238000007667 floating Methods 0.000 description 11
- 229920000139 polyethylene terephthalate Polymers 0.000 description 10
- 239000005020 polyethylene terephthalate Substances 0.000 description 10
- -1 polyethylene terephthalate-1, 4-cyclohexanedimethanol Polymers 0.000 description 10
- 239000012528 membrane Substances 0.000 description 8
- 230000035882 stress Effects 0.000 description 6
- 150000002148 esters Chemical class 0.000 description 5
- 238000002844 melting Methods 0.000 description 5
- 230000008018 melting Effects 0.000 description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical group O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 238000006136 alcoholysis reaction Methods 0.000 description 4
- QPKOBORKPHRBPS-UHFFFAOYSA-N bis(2-hydroxyethyl) terephthalate Chemical compound OCCOC(=O)C1=CC=C(C(=O)OCCO)C=C1 QPKOBORKPHRBPS-UHFFFAOYSA-N 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 239000005995 Aluminium silicate Substances 0.000 description 3
- 235000012211 aluminium silicate Nutrition 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 3
- 230000006978 adaptation Effects 0.000 description 2
- 238000004132 cross linking Methods 0.000 description 2
- 238000013016 damping Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 230000001174 ascending effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 238000004513 sizing Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D7/00—Producing flat articles, e.g. films or sheets
- B29D7/01—Films or sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C37/00—Component parts, details, accessories or auxiliary operations, not covered by group B29C33/00 or B29C35/00
- B29C37/02—Deburring or deflashing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0018—Combinations of extrusion moulding with other shaping operations combined with shaping by orienting, stretching or shrinking, e.g. film blowing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/16—Articles comprising two or more components, e.g. co-extruded layers
- B29C48/18—Articles comprising two or more components, e.g. co-extruded layers the components being layers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/92—Measuring, controlling or regulating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C37/00—Component parts, details, accessories or auxiliary operations, not covered by group B29C33/00 or B29C35/00
- B29C2037/90—Measuring, controlling or regulating
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
Abstract
According to the production process of the regenerated environment-friendly polyester film and the regenerated PETG heat-shrinkable film, disclosed by the invention, the shrinkage rate in the process of producing the heat-shrinkable film by the regenerated polyester material is dynamically controlled by adding the shrinkage rate on-line detection device on the multilayer coextrusion production line, so that the problem of unstable shrinkage rate in the process of producing the heat-shrinkable film by the regenerated polyester material is solved; the problem of reduced printing performance on the surface of the recycled and regenerated polyester material is solved by adopting a three-layer composite structure that an outer-layer original PETG film is used for wrapping an inner-layer regenerated polyester film; the problem of poor ageing resistance is solved by adding the chain extender ADR4468 into the regenerated polyester material, so that the high-value recycling of the recycled and regenerated polyester material in the heat-shrinkable packaging film industry is realized, the production cost of the PETG heat-shrinkable film is reduced, and the economic benefit of enterprises is greatly improved while the environment-friendly effect is realized.
Description
Technical Field
The invention relates to the technical field of regenerated PETG heat-shrinkable films and production process control, in particular to a production process of a regenerated environment-friendly polyester film and a regenerated PETG heat-shrinkable film.
Background
When the polyester material is recycled, because of the complexity of the source of the recycled material, the physical and chemical indexes of the recycled and regenerated polyester material hardly reach the same level of the original polyester material, so that the recycled and regenerated polyester material hardly realizes high-value recycling; the method is characterized in that the shrinkage rate of the regenerated polyester material heat-shrinkable film is different under the same production process parameter conditions, and meanwhile, after the heat-shrinkable film of the regenerated polyester material is subjected to heat shrinkage, the problem of material tensile strength reduction can occur after the heat-shrinkable film of the regenerated polyester material is normally placed for a period of time, so that the recycled regenerated polyester material cannot be utilized in the heat-shrinkable film industry, and therefore, how to solve the problem becomes a key technical problem of high-value recycling of the regenerated polyester material in the heat-shrinkable film industry.
Disclosure of Invention
In order to overcome the defects in the background technology, the invention discloses a production process of a regenerated environment-friendly polyester film and a regenerated PETG heat-shrinkable film; the shrinkage rate on-line detection device is added on the multilayer coextrusion production line, so that the shrinkage rate when the regenerated polyester material is used for producing the heat-shrinkable film is dynamically controlled, and the problem of unstable shrinkage rate when the regenerated polyester material is recycled for producing the heat-shrinkable film is solved; the problem of reduced printing performance on the surface of the recycled and regenerated polyester material is solved by adopting a three-layer composite structure that an outer-layer original PETG film is used for wrapping an inner-layer regenerated polyester film; the problem of poor ageing resistance is solved by adding the chain extender into the recycled polyester material, so that the high-value recycling of the recycled polyester material in the heat-shrinkable packaging film industry is realized.
In order to achieve the aim of the invention, the invention adopts the following technical scheme: a production process of a regenerated environment-friendly polyester film adopts a three-layer coextrusion biaxial stretching production process, and the production process comprises the steps of rPETG (regenerated PETG) anti-aging granulation, feed mixing, melting plasticization, filtering extrusion, tape casting tabletting, longitudinal stretching, transverse stretching, trimming and rolling; wherein, the rPETG (regenerated PETG) anti-aging granulation is finished in advance before the production of the regenerated environment-friendly polyester film, and the rPETG (regenerated PETG) is prepared into rPETG (regenerated PETG) anti-aging granulation materials;
wherein the feed mixing comprises core film material feed mixing and surface film material feed mixing, wherein the melt plasticizing comprises core film material melt plasticizing and surface film material melt plasticizing, wherein the filtering extrusion comprises core film material filtering extrusion and surface film material filtering extrusion;
the material components of the core film material feed mixture are rPETG (regenerated PETG) anti-aging pelleting materials, trimming crushing materials and startup debugging waste pelleting materials, so that the trimming materials and the startup debugging waste materials generated in the production process are recycled, and the production cost of the PETG heat-shrinkable film is greatly reduced; the rPETG is obtained by carrying out alcoholysis on the recycled polyester material, converting the recycled polyester material into a polyester intermediate (BHET) and carrying out repolymerization and regeneration to obtain a regenerated PETG polyester material; adding a chain extender ADR4468 into the regenerated PETG polyester material, extruding and granulating at the melting temperature of 170-190 ℃ to obtain rPETG (regenerated PETG) anti-aging granules;
the material components of the surface film material feed mixture are PETG (polyethylene terephthalate-1, 4-cyclohexanedimethanol ester), PET (polyethylene terephthalate) and a slipping agent; PET (polyethylene terephthalate) is added into the surface film layer to further reduce the cost of the product; in the regenerated PETG heat-shrinkable film, as the core film layer and the surface film layer are both of the same type of polyester material with good compatibility, the problem of poor compatibility caused by factors such as molecular chain polarity, crystallinity and the like among different materials is avoided, so that the degree of compositing between the core film layer and the surface film layer is good, and layering, wrinkling and the like can not occur in the heat shrinkage process;
in the trimming process, two times of trimming are included; cutting edges for the first time to cut off the edge part of the regenerated environment-friendly polyester film clamped by the transverse stretching chain clamp, and cutting edges for the second time to cut off an on-line shrinkage rate continuous detection sample; the longitudinal relative shrinkage and the transverse relative shrinkage of the sample are continuously detected through detecting the on-line shrinkage, and the temperature parameters in the longitudinal stretching and transverse stretching processes are controlled in a feedback mode, so that the control of the longitudinal actual shrinkage and the transverse actual shrinkage of the regenerated film finished product is realized;
the production process of the regenerated environment-friendly polyester film adopts an online closed-loop feedback control technology of the actual shrinkage rate of the regenerated environment-friendly polyester film, so that the trimming waste and the trimming waste generated in the production process are recycled, and the thermal shrinkage rate of a final regenerated environment-friendly polyester film finished product is not influenced, and therefore, no waste is generated in the production process; wherein the waste materials generated by the first trimming and the second trimming are directly crushed by an automatic recovery device and then sent to a core film material feeding mixer; wherein, the debugging waste generated in the startup debugging stage is recycled, and then is uniformly granulated by a re-granulating device, and then quantitatively mixed into the core film material for reuse.
Further, the filtering extrusion temperature of the core membrane material is 240-260 ℃, and the filtering extrusion temperature of the surface membrane material is 245-265 ℃; during the extrusion process of the core film layer, the temperature of the rPETG (regenerated PETG) anti-aging pelleting material is far higher than 200 ℃, and at the moment, the rPETG (regenerated PETG) rapidly completes crosslinking under the action of a chain extender ADR4468;
the longitudinal stretching preheating temperature is 100-115 ℃, the longitudinal stretching temperature is 80-90 ℃, the longitudinal stretching multiplying power is 1.0-3.0, the longitudinal stretching shaping temperature is 70-85 ℃, and the shaping time is 2-5S;
the transverse stretching temperature is 80-100 ℃, the transverse stretching multiplying power is 4-5.5 times, the transverse stretching shaping temperature is 70-85 ℃, and the transverse stretching shaping time is 5-10S.
Further, the actual shrinkage rate of the regenerated environment-friendly polyester film is controlled by controlling the longitudinal stretching temperature and the transverse stretching temperature in a feedback way through the longitudinal relative shrinkage rate and the transverse relative shrinkage rate measured by the shrinkage rate on-line detection device.
Preferably, the actual shrinkage rate control of the regenerated environment-friendly polyester film is realized by controlling the longitudinal stretching and shaping temperature and the transverse stretching and shaping temperature in a feedback way through the longitudinal relative shrinkage rate and the transverse relative shrinkage rate measured by the shrinkage rate on-line detection device.
Further, the shrinkage online detection device is fixedly arranged at the side of the winding machine; the shrinkage rate online detection device is provided with a feeding traction roller set, a thermal shrinkage device, a discharging traction roller set, a deflection roller set, a linear laser and an industrial camera; two traction rollers which are in up-down collision are arranged in the feeding traction roller set and the discharging traction roller set, and are used for clamping and dragging the on-line shrinkage rate continuous detection sample to pass through an on-line detection device; one end of a lower traction roller of the feeding traction roller set is connected with a servo motor through a coupler, and two ends of the lower traction roller of the discharging traction roller set are respectively connected with the servo motor through magnetic powder clutches; the pressure sensor is arranged in the deflection roller set and used for detecting the traction tension of the discharge traction roller set; when the shrinkage online detection device works, a second trimming cutting and online shrinkage continuous detection sample enters a thermal shrinkage device through a feeding traction roller set, a thermal shrinkage cavity is arranged in the thermal shrinkage device, a thermal shrinkage temperature of 90 ℃ is arranged in the thermal shrinkage cavity, the thermal shrinkage temperature of 90 ℃ enables the online shrinkage continuous detection sample in the thermal shrinkage cavity to shrink, then the online shrinkage continuous detection sample passes through the offset roller set in an S-shaped rewinding mode, and finally passes through the online detection device through the traction of the discharging traction roller set under the set 1.0N tension; when the shrinkage rate continuously detects that a sample is shrunk in the thermal shrinkage device, the rotation speed of the discharge traction roller set automatically tracks the shrinkage change of the continuously detected sample, so that the rotation speeds of the feed traction roller set and the discharge traction roller set are different, and the longitudinal relative shrinkage rate is calculated through the rotation speeds of the discharge traction roller set and the feed traction roller set; when the longitudinal shrinkage is measured, due to the influence of 1.0N tension, the measured longitudinal relative shrinkage is deviated from the actual longitudinal shrinkage of the PETG heat-shrinkable film, the deviation can be calibrated through experiments, a corresponding relation curve of the longitudinal relative shrinkage of the PETG heat-shrinkable film and the actual longitudinal shrinkage of the PETG heat-shrinkable film is obtained, and then the corresponding relation curve is arranged in a productivity control system;
when the shrinkage rate online detection device works, the linear laser emits linear laser, irradiates on the online shrinkage rate continuous detection sample after heat shrinkage at a set inclination angle, reflects the online shrinkage rate continuous detection sample after heat shrinkage to an industrial camera, and detects the length of the linear laser, wherein the length of the linear laser is the width of the online shrinkage rate continuous detection sample after heat shrinkage, and the transverse relative shrinkage rate can be calculated through the width of the online shrinkage rate continuous detection sample after heat shrinkage and the width of the online shrinkage rate continuous detection sample before heat shrinkage; when the transverse shrinkage is measured, the width of a sample is continuously detected through the online shrinkage of the discharge traction roller set, and the width is actually influenced by the set 1.0N tension, so that the deviation exists between the transverse relative shrinkage and the actual transverse shrinkage of the PETG heat-shrinkable film, the deviation is calibrated through an experiment, a corresponding relation curve of the transverse relative shrinkage of the PETG heat-shrinkable film and the actual transverse shrinkage of the PETG heat-shrinkable film is obtained, and then the curve is arranged in a production line control system;
the 1.0N tension setting of the discharging traction roller set is realized by the cooperation of a magnetic powder clutch and a servo motor which are respectively arranged at two ends of a lower traction roller of the discharging traction roller set, and the specific realization method is as follows: assuming that the winding linear speed of a winding machine of a production line is 100 m/min, the longitudinal shrinkage rate of a regenerated PETG heat-shrinkable film is 30%, the diameter of a traction roller is 50mm, when a sample continuously detected by the second trimming and cutting on-line shrinkage rate passes through a shrinkage rate on-line detection device, the rotating speed of a feeding traction roller set is about 637 revolutions per minute, the theoretical rotating speed of a discharging traction roller set is about 446 revolutions per minute, and the actual rotating speed of the discharging traction roller set fluctuates around 446 revolutions per minute because the actual shrinkage rate of the continuously detected sample on-line shrinkage rate deviates from 30%; when the shrinkage online detection device works, the rotating speed 637 of the feeding traction roller set is synchronous with the winding linear speed of a production line winding machine by 100 m/min, the rotating speed of a servo motor at one end of a lower traction roller of the discharging traction roller set is set to 471 r/min (446+25 r/min), the working torque of a magnetic powder clutch at the same side is set to 0.5NM, the driving torque is provided for the lower traction roller, the rotating speed of the servo motor at the other end is set to 421 r/min (446-25 r/min) in the same direction, and the working torque of the magnetic powder clutch at the same side is initially set to 0.4NM, so that damping torque is provided for the lower traction roller; because the servo motors at the two ends of the lower traction roller of the discharging traction roller set have a rotating speed difference, the torque acting on the lower traction roller is the difference between the driving torque and the damping torque, namely the traction torque of the discharging traction roller set; in the above example, the traction torque acting on the traction roller under the discharging traction roller set is 0.1NM (friction is not considered), namely, the discharging traction roller set applies traction tension of 4.0N to the continuously detected sample at the linear shrinkage rate, and the pressure sensor in the offset roller set detects traction tension of 8.0N (which is 2 times of the traction tension on the continuously detected sample at the linear shrinkage rate); the traction tension applied by the discharging traction roller set to the on-line shrinkage rate continuous detection sample can be changed by changing the difference value of the working torques of the two magnetic powder clutches acting on the lower traction roller through changing the ascending (or descending) of the working torque of the magnetic powder clutch at one side; if the working torque of the magnetic powder clutch at one side is 0.5NM and the working torque of the magnetic powder clutch at the other side is 0.475NM, the traction torque acting on the traction roller under the discharging traction roller set is 0.025NM, and the traction tension applied by the discharging traction roller set to the on-line shrinkage rate continuous detection sample is 1.0N; in actual traction tension control of the discharge traction roller set, because the discharge traction roller set has other factors such as friction, the traction tension of the discharge traction roller set actually obtained by directly controlling the working torque of the magnetic powder clutch is not 1.0N, so that the traction tension value detected by the pressure sensor in the bias roller set is needed, the working torque of the magnetic powder clutch at one side is fed back to be controlled to rise (or fall), the tension value detected by the pressure sensor is stably kept at 2.0N, and the traction tension of the discharge traction roller set is stably controlled at 1.0N;
under the condition of setting 1.0N traction tension, the automatic tracking process of the rotation speed of the discharge traction roller set for continuously detecting the shrinkage change of the sample on-line shrinkage is as follows: when the longitudinal shrinkage rate of the regenerated PETG heat shrinkage film is more than 30%, the length of the on-line shrinkage rate continuous detection sample flowing out after passing through the heat shrinkage device is shortened, if the discharging traction roller set continues to rotate at the theoretical rotating speed of 446 revolutions per minute, the on-line shrinkage rate continuous detection sample is stretched to enable the length of the on-line shrinkage rate continuous detection sample to be recovered to the original length, the traction force applied to the on-line shrinkage rate continuous detection sample is increased and is larger than the 1.0N traction tension provided by the discharging traction roller set, and therefore the rotating speed of the discharging traction roller set is automatically reduced; when the longitudinal shrinkage rate of the regenerated PETG heat shrinkage film is less than 30%, the length of an online shrinkage rate continuous detection sample flowing out after passing through the heat shrinkage device is prolonged, if the discharge traction roller set continuously rotates at a theoretical rotation speed of 446 revolutions per minute, the online shrinkage rate continuous detection sample is loosened, and at the moment, the tension of the online shrinkage rate continuous detection sample pulled by the discharge traction roller set is less than 1.0N traction tension provided by the discharge traction roller set, so that the rotation speed of the discharge traction roller set is automatically increased, and the automatic tracking of the change of the shrinkage of the online shrinkage rate continuous detection sample by the rotation speed of the discharge traction roller set is realized;
supplementary explanation: in the online detection device, as the traction force required to be provided by the discharging traction roller set is only 1.0N, the existing magnetic powder clutch of a commercial finished product cannot meet the requirement, the magnetic powder clutches are arranged at the two ends of the lower traction roller of the discharging traction roller set, and the design requirement is met through the difference of the working torque of the two magnetic powder clutches; in addition, the servo motors are arranged at the two ends of the lower traction roller of the discharging traction roller group, so that the problem that when a single motor is arranged, the magnetic powder clutch generates heat due to the fact that the rotating speed difference between the input shaft and the output shaft of the magnetic powder clutch is too high is solved.
Further, the calculation formula of the longitudinal relative shrinkage is as follows: sd= (R0-R)/R0 is 100%; sd is longitudinal relative shrinkage, wherein R0 is the rotating speed of the feeding traction roller set, and R is the rotating speed of the discharging traction roller set;
the calculation formula of the transverse relative shrinkage is as follows: st= (W0-W)/w0×100%; where St is the transverse relative shrinkage, where W0 is the original width of the continuously measured sample at the line shrinkage, and W is the width of the continuously measured sample at the line shrinkage after passing through the heat shrinkage apparatus.
Further, the relative relation curve between the longitudinal relative shrinkage and the transverse relative shrinkage of the regenerated PETG heat-shrinkable film and the actual longitudinal shrinkage and the transverse shrinkage of the regenerated PETG heat-shrinkable film is obtained through experiments and is arranged in a production line control system.
The regenerated PETG heat-shrinkable film is of a three-layer composite structure and comprises a surface film layer and a core film layer clamped between the two surface film layers; the surface film layer is made of the same material, and comprises 64-98 parts by mass of PETG (polyethylene terephthalate-1, 4-cyclohexanedimethanol ester), 0-30 parts by mass of PET (polyethylene terephthalate) and 2-6 parts by mass of slipping agent; the components of the core film layer material comprise 90-100 parts by mass of rPETG (regenerated PETG) anti-aging pelleting material and 0-10 parts by mass of start-up debugging waste pelleting material, and the trimming crushing material is added into the core film layer material along with the line for mixing.
Further, the rPETG (regenerated PETG) anti-aging granulation material comprises 99.5-99 parts by mass of rPETG (regenerated PETG) and 0.5-1.0 parts by mass of chain extender ADR4468; the granulating process is as follows: rPETG (regenerated PETG) was dried at 65 ℃ for 4 hours; then the chain extender ADR4468 is added and fully mixed; extruding and granulating at 170-190 ℃ by adopting a double-screw extruder to prepare rPETG (regenerated PETG) anti-aging granules with the particle size of 2 mm; in the production process of rPETG (regenerated PETG) anti-aging granulating materials, the temperature of each section of the double-screw extruder is controlled to be increased from 160 ℃ to 180 ℃, and the extrusion temperature is not higher than 190 ℃ at most, so that rapid crosslinking in the granulating process is prevented.
Further, the total thickness of the regenerated PETG heat-shrinkable film is 20-50 μm; the thickness of the surface film layer is equal and is 2-5 mu m; the longitudinal shrinkage is 1-30% and the transverse shrinkage is 50-80%.
Further, the slipping agent is silicon dioxide or kaolin.
Due to the adoption of the technical scheme, the invention has the following beneficial effects: according to the production process of the regenerated environment-friendly polyester film and the regenerated PETG heat-shrinkable film, disclosed by the invention, the shrinkage rate in the process of producing the heat-shrinkable film by the regenerated polyester material is dynamically controlled by adding the shrinkage rate on-line detection device on the multilayer coextrusion production line, so that the problem of unstable shrinkage rate in the process of producing the heat-shrinkable film by the regenerated polyester material is solved; the problem of reduced printing performance on the surface of the recycled and regenerated polyester material is solved by adopting a three-layer composite structure that an outer-layer original PETG film is used for wrapping an inner-layer regenerated polyester film; the problem of poor ageing resistance is solved by adding the chain extender into the regenerated polyester material, so that the high-value recycling of the recycled and regenerated polyester material in the heat-shrinkable packaging film industry is realized, the production cost of the PETG heat-shrinkable film is reduced, and the economic benefit of enterprises is greatly improved while the environment-friendly effect is realized.
Drawings
FIG. 1 is a flow chart of a process for producing a regenerated environment-friendly polyester film;
FIG. 2 is a schematic cross-sectional view of a regenerated PETG heat shrink film;
FIG. 3 is a schematic view of the appearance of the shrinkage on-line detecting device;
FIG. 4 is a schematic view of the feed roll set;
FIG. 5 is an exploded view of the heat shrink device;
FIG. 6 is a schematic view of the external appearance of the discharging traction roller set;
FIG. 7 is a schematic view of the outer appearance of a deflector roll set;
FIG. 8 is a schematic view showing the state of the sample being wound around the deflector roll group continuously measured in the linear shrinkage.
In the figure: 1. a bottom plate; 2. a feed pull roll set; 2.1, a feeding traction roller; 2.2, a servo motor; 2.3, a coupler; 3. a thermal shrinkage device; 3.1, a lower thermal shrinkage box body; 3.1.1, infrared heating tube; 3.1.2, a temperature sensor; 3.2, feeding a heat shrinkage box body; 4. a discharging traction roller set; 4.1, a discharging traction roller; 4.2, a servo motor A;4.3, a magnetic powder clutch A;4.4, a magnetic powder clutch B;4.5, servo motor B;4.6, a speed measuring sensor; 5. a deflection roller set; 5.1, fixing the deflection roller set; 5.1.1, fixing the deflection roller; 5.1.2, bearing seat; 5.2, floating deflection roller groups; 5.2.1, floating deflection roller; 5.2.2, floating seat; 5.2.3, guide rails; 5.2.4, a guide rail seat; 5.2.5, pressure sensor; 6. a line laser; 7. an industrial camera; 8. continuously detecting a sample at the linear shrinkage; 8.1, a surface film layer; 8.2, a core film layer.
Detailed Description
The invention will be explained in more detail by the following examples, the purpose of which is to protect all technical improvements within the scope of the invention.
Example 1
The regenerated PETG heat-shrinkable film has a three-layer composite structure, and comprises a surface film layer 8.1 and a core film layer 8.2 clamped between the two surface film layers 8.1; the total thickness is 20 mu m, and the thickness of the surface film layer is 2 mu m; the longitudinal shrinkage is 1% and the transverse shrinkage is 80%;
the surface film layer 8.1 is the same in material, and comprises 94 parts by mass of PETG (polyethylene terephthalate-1, 4-cyclohexanedimethanol ester) and 6 parts by mass of a slipping agent, wherein the slipping agent adopts silicon dioxide; the components of the core film layer material are 100 parts by mass of rPETG (regenerated PETG) anti-aging granular materials, and the trimming crushed materials are added into the core film layer material along with the line for mixing; wherein rPETG is a regenerated PETG polyester material obtained by carrying out alcoholysis on the recycled polyester material, converting the recycled polyester material into a polyester intermediate (BHET) and carrying out repolymerization; wherein the rPETG (regenerated PETG) anti-aging granulation material comprises 99.5 parts by mass of rPETG and 0.5 parts by mass of chain extender ADR4468, and the rPETG (regenerated PETG) is dried for 4 hours at 65 ℃; then fully mixing the mixture with a chain extender ADR4468, extruding and granulating the mixture at the melting temperature of 180 ℃ by adopting a double-screw extruder to prepare rPETG (regenerated PETG) anti-aging granules with the particle size of 2 mm;
the production process flow of the regenerated PETG heat-shrinkable film is shown in figure 1 of the specification, and the specific procedures comprise rPETG (regenerated PETG) anti-aging granulation, feed mixing, melt plasticizing, filtering extrusion, tape casting tabletting, longitudinal stretching, transverse stretching, trimming and rolling; wherein, the rPETG (regenerated PETG) anti-aging granulation is finished in advance before the production of the regenerated environment-friendly polyester film, and the rPETG (regenerated PETG) is prepared into rPETG (regenerated PETG) anti-aging granulation materials;
wherein the feed mixing comprises core film material feed mixing and surface film material feed mixing, wherein the melt plasticizing comprises core film material melt plasticizing and surface film material melt plasticizing, wherein the filtering extrusion comprises core film material filtering extrusion and surface film material filtering extrusion, and the filter adopts a 20 mu m disc filter;
the production process parameters of the regenerated PETG heat shrink film of the embodiment are as follows:
the filtering extrusion temperature of the core membrane material is 255 ℃, and the filtering extrusion temperature of the surface membrane material is 260 ℃;
the longitudinal stretching preheating temperature is 110 ℃, the longitudinal stretching temperature is 90 ℃, the longitudinal stretching multiplying power is 1.1, the longitudinal stretching shaping temperature is 70 ℃, and the shaping time is 3S; because the longitudinal shrinkage rate of the regenerated PETG heat-shrinkable film finished product is extremely small, the high stretching temperature and the low stretching multiplying power are adopted, the motion capability of a polyester material molecular chain segment is improved, the molecular chain segment can be relatively quickly adapted to stretching orientation, and the relaxation process is completed, so that the internal stress is reduced, and the longitudinal shrinkage rate of the finished film is reduced;
the transverse stretching temperature is 85 ℃, the transverse stretching multiplying power is 5.0 times, the transverse stretching shaping temperature is 75 ℃, and the transverse stretching shaping time is 10S; because the regenerated PETG heat-shrinkable film finished product has extremely high transverse shrinkage rate, the low stretching temperature, the low shaping temperature and the high stretching multiplying power are adopted, the motion capability of a polyester material molecular chain segment is reduced, the molecular chain segment orientation before stretching is kept as far as possible, the relaxation process cannot be completed, and the internal stress after stretching is increased, so that the transverse shrinkage rate of the finished film is ensured;
in the trimming process, two times of trimming are included; cutting edges for the first time to cut off the edge part of the regenerated environment-friendly polyester film clamped by the transverse stretching chain clamp, cutting edges for the second time to cut off an on-line shrinkage continuous detection sample, wherein the width of the on-line shrinkage continuous detection sample is 30mm; the on-line shrinkage rate continuous detection sample passes through an on-line shrinkage rate detection device fixedly arranged on the side of the winding machine, and the longitudinal stretching temperature or the longitudinal stretching shaping temperature in the longitudinal stretching process is controlled by the detected longitudinal relative shrinkage rate in a feedback manner, so that the actual longitudinal shrinkage rate of the finished film is controlled; the transverse stretching temperature or the transverse stretching shaping temperature in the transverse stretching process is controlled in a feedback mode through the detected transverse relative shrinkage rate, so that the actual transverse shrinkage rate of the finished film is controlled;
the shrinkage online detection device is fixedly arranged at the side of the winding machine, and the structure diagram is shown in figure 3 of the specification; the shrinkage online detection device comprises a bottom plate 1, a feeding traction roller set 2, a thermal shrinkage device 3, a discharging traction roller set 4, a deflection roller set 5, a linear laser 6 and an industrial camera 7, wherein the feeding traction roller set 2, the thermal shrinkage device 3, the deflection roller set 5 and the discharging traction roller set 4 are fixedly arranged on the upper part of the bottom plate 1 in sequence; referring to fig. 4 of the specification, a feeding traction roller set 2 comprises a pair of feeding traction rollers 2.1 which are abutted up and down, wherein the feeding traction rollers 2.1 positioned at the lower side are connected with a servo motor 2.2 through a coupler 2.3, and the rotating speed of the servo motor 2.2 is directly controlled by a production line control system according to the winding linear speed of a winding machine; the thermal shrinkage device 3 is arranged between the feeding traction roller set 2 and the deflection roller set 5, and referring to the accompanying drawing 5 in the specification, the thermal shrinkage device 3 comprises a lower thermal shrinkage box body 3.1 and an upper thermal shrinkage box body 3.2, infrared heating pipes 3.1.1 are fixedly arranged in the lower thermal shrinkage box body 3.1 and the upper thermal shrinkage box body 3.2, and a temperature sensor 3.1.2 is fixedly arranged in the lower thermal shrinkage box body 3.1; the lower heat shrinkage box body 3.1 and the upper heat shrinkage box body 3.2 are fixedly connected to form a hollow heat shrinkage cavity, the heat shrinkage cavity is heated by an infrared heating pipe 3.1.1 and is controlled by a temperature sensor 3.1.2 in a feedback manner, so that the heat shrinkage cavity is stably kept at a set 110 ℃; a feeding hole is formed in one side of the heat shrinkage cavity adjacent to the feeding traction roller group 2, and a discharging hole is formed in one side of the heat shrinkage cavity adjacent to the deflection roller group 5; referring to fig. 7 and 8 of the specification, the deflection roller set 5 comprises a fixed deflection roller 5.1.1, a floating deflection roller 5.2.1 and a guide rail 5.2.3; the two guide rails 5.2.3 are arranged on the bottom plate 1 in parallel through a pair of guide rail seats 5.2.4; the fixed deflection roller 5.1.1 is rotatably arranged at the left side of the guide rail 5.2.3 through the bearing seat 5.1.2, the floating deflection roller 5.2.1 is in sliding connection with the guide rail 5.2.3 through the floating seat 5.2.2, and the floating deflection roller 5.2.1 is rotatably connected with the floating seat 5.2.2; a pressure sensor 5.2.5 is fixedly arranged between the floating seat 5.2.2 and the guide rail seat 5.2.4; the discharging traction roller set 4 comprises a pair of discharging traction rollers 4.1 which are in up-down collision, one end of the discharging traction roller 4.1 positioned at the lower side is connected with a servo motor A4.2 through a magnetic powder clutch A4.3, the other end of the discharging traction roller is connected with a servo motor B4.5 through a magnetic powder clutch B4.4, and a speed sensor 4.6 is fixedly arranged at one end of the discharging traction roller 4.1 positioned at the upper side and used for detecting the rotating speed of the discharging traction roller 4.1 in up-down collision; the linear laser 6 and the industrial camera 7 are fixedly arranged at the upper part of the deflection roller set 5 through a bracket;
before the on-line shrinkage rate detection device works, firstly, a plurality of experiments are carried out in a laboratory to obtain a corresponding relation curve relationship between the longitudinal relative shrinkage rate and the transverse relative shrinkage rate of the regenerated PETG heat-shrinkable film and the actual longitudinal shrinkage rate and the transverse shrinkage rate of the regenerated PETG heat-shrinkable film, and the corresponding relation curve is arranged in a control system of a heat-shrinkable film production line;
when the shrinkage online detection device works, a sample 8 continuously detected in the shrinkage online detection device enters a thermal shrinkage device 3 through a feeding traction roller set 2, passes through the thermal shrinkage device, passes through a fixed deflection roller 5.1.1 and a floating deflection roller 5.2.1 of a deflection roller set 5 in an S-shaped rewinding mode, and finally passes through a discharging traction roller set 4 to be drawn and flows out of the online detection device; the rotating speed of the feeding traction roller group 2 is set to be the same as the winding linear speed of the winding machine by 100 m/min and is 636.94 r/min; the rotating speed of the discharging traction roller set 4 is calculated according to the longitudinal shrinkage rate of the regenerated PETG heat-shrinkable film of 1%, and the theoretical rotating speed is 630.57 revolutions per minute; the rotating speed of a servo motor A4.2 at one end of a lower traction roller of the discharging traction roller group 4 is set to 626 revolutions per minute, and the working torque of a magnetic powder clutch A4.3 at the same side is set to 0.5NM; the rotating speed of a servo motor B4.5 at the other end of the lower traction roller of the discharging traction roller group 4 is set to be 601 revolutions per minute, and the working torque of a magnetic powder clutch B4.4 at the same side is initially set to be 0.4NM; the pressure sensor 5.2.5 detects the traction tension borne by the floating deflection roller 5.2.1 (2 times of the tension of the sample 8 continuously detected at the linear shrinkage rate), the feedback control reduces the working torque of the magnetic powder clutch B4.4, so that the traction tension detected by the pressure sensor 5.2.5 is stably kept at 2.0N, namely the discharge traction roller set 4 stably applies 1.0N traction tension to the sample 8 continuously detected at the linear shrinkage rate; when the longitudinal shrinkage of the on-line shrinkage continuous detection sample 8 is changed from 1% to 2%, the rotation speed of the discharging traction roller 4.1 of the discharging traction roller set 4 is automatically changed to 625.21R/min (higher than a theoretical value due to the influence of traction tension), and according to a longitudinal relative shrinkage calculation formula, the longitudinal relative shrinkage is calculated as sd= (R0-R)/r0% = (636.94-625.21)/636.94 x 100% = 1.84%, and the longitudinal relative shrinkage is calculated by a corresponding relation curve to obtain the longitudinal actual shrinkage of 2% of the finished film, and then the longitudinal stretching temperature is increased by using the feedback control of the measured longitudinal actual shrinkage of 2%, so that the longitudinal actual shrinkage of the finished film is stabilized at 1%; or the measured longitudinal actual shrinkage rate is utilized to increase the longitudinal stretching and shaping temperature by 2% feedback control, so that the longitudinal actual shrinkage rate of the finished film is stabilized at 1%;
when the shrinkage rate online detection device works, a linear laser 6 emits linear laser, the linear laser irradiates on a heat-shrunk online heat shrinkage rate continuous detection sample 8 at a certain angle, the linear laser is reflected to an industrial camera 7 by the heat-shrunk online heat shrinkage rate continuous detection sample 8, the length of the linear laser is measured, the length of the linear laser is the width W of the heat-shrunk online heat shrinkage rate continuous detection sample, then the transverse relative shrinkage rate is calculated by using a transverse relative shrinkage rate calculation formula, and then the actual shrinkage rate of a finished film is calculated by using a curve corresponding to the transverse relative shrinkage rate and the transverse actual shrinkage rate of the finished film, and the transverse stretching temperature or the transverse stretching shaping temperature is controlled by using the calculated actual shrinkage rate feedback of the finished film, so that the transverse actual shrinkage rate of the finished film is stabilized at 80%; for example, when the transverse shrinkage of the continuous detection sample 8 of the linear shrinkage is changed from 80% to 78%, the length of the linear laser light measured in the industrial camera 7 is 6.8mm (less than the theoretical value due to the influence of the traction tension), the transverse relative shrinkage is calculated as st= (W0-W)/W0 x 100% = (30-6.45)/30 x 100% = (78.5%) according to the transverse relative shrinkage calculation formula, the transverse relative shrinkage is calculated by the corresponding relation curve, the transverse actual shrinkage of the finished film is 78%, and then the transverse stretching temperature is reduced by using the measured 78% feedback control of the transverse actual shrinkage, so that the transverse actual shrinkage of the finished film is stabilized at 80%; or reducing the transverse stretching and shaping temperature by using the feedback control of the measured transverse actual shrinkage rate of 78 percent, so that the transverse actual shrinkage rate of the finished film is stabilized at 80 percent.
Example two
The regenerated PETG heat-shrinkable film is of a three-layer composite structure and comprises a surface film layer 8.1 and a core film layer 8.2 clamped between the two surface film layers 8.1; the total thickness is 30 mu m, and the thickness of the surface film layer is 4 mu m; the longitudinal shrinkage is 15% and the transverse shrinkage is 65%;
the surface film layer 8.1 is made of the same material, and comprises 76 parts by mass of PETG (polyethylene terephthalate-1, 4-cyclohexanedimethanol ester), 20 parts by mass of PET (polyethylene terephthalate), 4 parts by mass of a slipping agent, wherein the slipping agent is kaolin; the core film layer material comprises 95 parts by mass of rPETG (regenerated PETG) anti-aging pelleting material, 5 parts by mass of start-up debugging waste pelleting material, and trimming and crushing materials are added into the core film layer material along with a line for mixing; wherein rPETG is a regenerated PETG polyester material obtained by carrying out alcoholysis on the recycled polyester material, converting the recycled polyester material into a polyester intermediate (BHET) and carrying out repolymerization; wherein the rPETG (regenerated PETG) anti-aging granulation material comprises 99 parts by mass of rPETG and 1.0 part by mass of chain extender ADR4468, and the rPETG (regenerated PETG) is dried at 65 ℃ for 4 hours; then fully mixing the mixture with a chain extender ADR4468, extruding and granulating the mixture at the melting temperature of 180 ℃ by adopting a double-screw extruder to prepare rPETG (regenerated PETG) anti-aging granules with the particle size of 2 mm;
the production process flow of the regenerated PETG heat-shrinkable film is shown in figure 1 of the specification, and the specific procedures comprise rPETG (regenerated PETG) anti-aging granulation, feed mixing, melt plasticizing, filtering extrusion, tape casting tabletting, longitudinal stretching, transverse stretching, trimming and rolling; wherein, the rPETG (regenerated PETG) anti-aging granulation is finished in advance before the production of the regenerated environment-friendly polyester film, and the rPETG (regenerated PETG) is prepared into rPETG (regenerated PETG) anti-aging granulation materials;
wherein the feed mixing comprises core film material feed mixing and surface film material feed mixing, wherein the melt plasticizing comprises core film material melt plasticizing and surface film material melt plasticizing, wherein the filtering extrusion comprises core film material filtering extrusion and surface film material filtering extrusion, and the filter adopts a 20 mu m disc filter;
the production process parameters of the regenerated PETG heat shrink film of the embodiment are as follows:
the filtering extrusion temperature of the core membrane material is 250 ℃, and the filtering extrusion temperature of the surface membrane material is 255 ℃;
the longitudinal stretching preheating temperature is 105 ℃, the longitudinal stretching temperature is 85 ℃, the longitudinal stretching multiplying power is 1.2, the longitudinal stretching shaping temperature is 85 ℃, and the shaping time is 4S; the longitudinal shrinkage rate of the regenerated PETG heat-shrinkable film finished product is moderate, and the equal stretching temperature and the sizing temperature and the lower stretching multiplying power are adopted, so that the motion capability of a polyester material molecular chain segment is properly reduced, the stretching orientation of the molecular chain segment is adapted to the moderate relaxation process, and a certain internal stress is kept, so that the longitudinal shrinkage rate of the finished film is ensured;
the transverse stretching temperature is 90 ℃, the transverse stretching multiplying power is 4.5 times, the transverse stretching shaping temperature is 80 ℃, and the transverse stretching shaping time is 8S; the transverse shrinkage rate of the regenerated PETG heat-shrinkable film finished product is moderate, moderate stretching temperature, low shaping temperature and moderate stretching multiplying power are adopted, so that the motion capability of a polyester material molecular chain segment is reduced, the stretching orientation of the molecular chain segment is adapted to the relaxation process is moderate, a certain internal stress is kept, and the transverse shrinkage rate of the finished film is ensured;
the actual machine direction shrinkage and the actual transverse direction shrinkage of the finished film of this example were controlled in the same manner as in example one.
Example III
The regenerated PETG heat-shrinkable film is of a three-layer composite structure and comprises a surface film layer 8.1 and a core film layer 8.2 clamped between the two surface film layers 8.1; the total thickness is 50 mu m, and the thickness of the surface film layer is 5 mu m; the longitudinal shrinkage is 30% and the transverse shrinkage is 50%;
the surface film layer 8.1 is made of the same material, and comprises 68 parts by mass of PETG (polyethylene terephthalate-1, 4-cyclohexanedimethanol ester), 30 parts by mass of PET (polyethylene terephthalate), 2 parts by mass of a slipping agent, wherein the slipping agent is kaolin; the components of the core film layer material are 98 parts by mass of rPETG (regenerated PETG) anti-aging pelleting materials, 2 parts by mass of startup debugging waste pelleting materials, and trimming broken materials are added into the core film layer material along with a line for mixing; wherein rPETG is a regenerated PETG polyester material obtained by carrying out alcoholysis on the recycled polyester material, converting the recycled polyester material into a polyester intermediate (BHET) and carrying out repolymerization; wherein the rPETG (regenerated PETG) anti-aging granulation material comprises 99.3 parts by mass of rPETG and 0.7 parts by mass of chain extender ADR4468, and the rPETG (regenerated PETG) is dried for 4 hours at 65 ℃; then fully mixing the mixture with a chain extender ADR4468, extruding and granulating the mixture at the melting temperature of 180 ℃ by adopting a double-screw extruder to prepare rPETG (regenerated PETG) anti-aging granules with the particle size of 2 mm;
the production process flow of the regenerated PETG heat-shrinkable film is shown in figure 1 of the specification, and the specific procedures comprise rPETG (regenerated PETG) anti-aging granulation, feed mixing, melt plasticizing, filtering extrusion, tape casting tabletting, longitudinal stretching, transverse stretching, trimming and rolling; wherein, the rPETG (regenerated PETG) anti-aging granulation is finished in advance before the production of the regenerated environment-friendly polyester film, and the rPETG (regenerated PETG) is prepared into rPETG (regenerated PETG) anti-aging granulation materials;
wherein the feed mixing comprises core film material feed mixing and surface film material feed mixing, wherein the melt plasticizing comprises core film material melt plasticizing and surface film material melt plasticizing, wherein the filtering extrusion comprises core film material filtering extrusion and surface film material filtering extrusion, and the filter adopts a 20 mu m disc filter;
the production process parameters of the regenerated PETG heat shrink film of the embodiment are as follows:
the filtering extrusion temperature of the core membrane material is 245 ℃, and the filtering extrusion temperature of the surface membrane material is 250 ℃;
the longitudinal stretching preheating temperature is 100 ℃, the longitudinal stretching temperature is 85 ℃, the longitudinal stretching multiplying power is 1.5, the longitudinal stretching shaping temperature is 85 ℃, and the shaping time is 3S; because the longitudinal shrinkage rate of the regenerated PETG heat-shrinkable film finished product is larger, the longitudinal shrinkage rate of the finished film is ensured by adopting equal stretching temperature and setting temperature and slightly higher stretching multiplying power and properly controlling stretching orientation adaptation and relaxation process, thereby keeping larger internal stress;
the transverse stretching temperature is 95 ℃, the transverse stretching multiplying power is 4.0 times, the transverse stretching shaping temperature is 85 ℃, and the transverse stretching shaping time is 6S; because the transverse shrinkage rate of the regenerated PETG heat-shrinkable film finished product is lower, the higher stretching temperature and the higher shaping temperature are adopted, the lower stretching multiplying power is adopted, the motion capability of a polyester material molecular chain segment is reduced, the stretching orientation adaptation and relaxation process of the molecular chain segment are accelerated, the internal stress is reduced, and the smaller transverse shrinkage rate of the finished film is ensured;
the actual machine direction shrinkage and the actual transverse direction shrinkage of the finished film of this example were controlled in the same manner as in example one.
The invention is not described in detail in the prior art.
Claims (7)
1. A production process of a regenerated environment-friendly polyester film is characterized by comprising the following steps: adopting a three-layer co-extrusion biaxial stretching production process, wherein the production process comprises the steps of rPETG ageing-resistant granulation, feed mixing, fusion plasticizing, filtering extrusion, tape casting tabletting, longitudinal stretching, transverse stretching, trimming and rolling; wherein rPETG anti-aging granulation is finished in advance before the production of the regenerated environment-friendly polyester film, and rPETG is prepared into rPETG anti-aging granules;
wherein the feed mixing comprises core film material feed mixing and surface film material feed mixing, wherein the melt plasticizing comprises core film material melt plasticizing and surface film material melt plasticizing, wherein the filtering extrusion comprises core film material filtering extrusion and surface film material filtering extrusion;
the material components of the core film material feed mixture are rPETG anti-aging pelletization, edge cutting crushing, startup debugging waste pelletization; the rPETG anti-aging granulation material comprises 99.5-99 parts by mass of rPETG and 0.5-1.0 parts by mass of chain extender ADR4468; the anti-aging granulation process comprises the following steps: rPETG was dried at 65 ℃ for 4 hours; fully mixing the mixed materials by adding a chain extender ADR4468; extruding and granulating at 170-190 ℃ by adopting a double-screw extruder;
the material components of the surface film material feed mixture are PETG, PET and slipping agent;
in the trimming process, two times of trimming are included; cutting off the edge part of the regenerated environment-friendly polyester film clamped by the transverse stretching chain clamp for the first time, and cutting off a continuous detection sample (8) of the on-line shrinkage rate for the second time; the longitudinal relative shrinkage and the transverse relative shrinkage of the sample (8) are continuously detected through detection of the on-line shrinkage, and the temperature parameters in the longitudinal stretching and transverse stretching processes are controlled through feedback, so that the control of the longitudinal actual shrinkage and the transverse actual shrinkage of the regenerated film finished product is realized;
the longitudinal relative shrinkage and the transverse relative shrinkage of the sample (8) are continuously detected at the linear shrinkage and detected by a shrinkage online detection device, and the shrinkage online detection device is fixedly arranged at the side of the winding machine; the shrinkage online detection device is provided with a feeding traction roller set (2), a thermal shrinkage device (3), a discharging traction roller set (4), a deflection roller set (5), a linear laser (6) and an industrial camera (7); two traction rollers which are in up-down collision are arranged in the feeding traction roller set (2) and the discharging traction roller set (4), one end of a lower traction roller of the feeding traction roller set (2) is connected with a servo motor (2.2) through a coupler (2.3), and two ends of the lower traction roller of the discharging traction roller set (4) are respectively connected with the servo motor through magnetic powder clutches; a pressure sensor (5.2.5) is arranged in the deflection roller set (5) and is used for detecting the traction tension of the discharge traction roller set (4); the discharging traction roller set (4) is used for continuously detecting the on-line shrinkage rate after passing through the thermal shrinkage device (3) through a magnetic powder clutch and a servo motor which are respectively arranged at two ends of the lower traction roller, and applying constant traction tension to the on-line shrinkage rate continuously detected sample; under the action of constant traction tension, the rotation speed of the traction roller of the discharging traction roller set (4) automatically follows the on-line shrinkage rate to continuously detect the longitudinal shrinkage rate change of the sample, and the longitudinal relative shrinkage rate is calculated through the rotation speeds of the discharging traction roller set (4) and the feeding traction roller set (2); the linear laser (6) emits linear laser, the industrial camera (7) shoots the linear laser width reflected by the sample continuously detected by the on-line shrinkage after passing through the thermal shrinkage device (3), and the transverse relative shrinkage is calculated by continuously detecting the width change of the sample before and after thermal shrinkage by the on-line shrinkage.
2. The process for producing the regenerated environment-friendly polyester film according to claim 1, which is characterized in that: the filtering extrusion temperature of the core film material is 240-260 ℃, and the filtering extrusion temperature of the surface film material is 245-265 ℃;
the longitudinal stretching preheating temperature is 100-115 ℃, the longitudinal stretching temperature is 80-90 ℃, the longitudinal stretching multiplying power is 1.0-3.0, the longitudinal stretching shaping temperature is 70-85 ℃, and the shaping time is 2-5S;
the transverse stretching temperature is 80-100 ℃, the transverse stretching multiplying power is 4-5.5 times, the transverse stretching shaping temperature is 70-85 ℃, and the transverse stretching shaping time is 5-10S.
3. The process for producing the regenerated environment-friendly polyester film according to claim 1, which is characterized in that: the actual shrinkage rate control of the regenerated environment-friendly polyester film is realized by controlling the longitudinal stretching temperature and the transverse stretching temperature in a feedback way through the longitudinal relative shrinkage rate and the transverse relative shrinkage rate measured by the shrinkage rate on-line detection device.
4. The process for producing the regenerated environment-friendly polyester film according to claim 1, which is characterized in that: the actual shrinkage rate control of the regenerated environment-friendly polyester film is realized by controlling the longitudinal stretching and shaping temperature and the transverse stretching and shaping temperature through feedback by the longitudinal relative shrinkage rate and the transverse relative shrinkage rate measured by the shrinkage rate on-line detection device.
5. The process for producing the regenerated environment-friendly polyester film according to claim 4, which is characterized in that: the calculation formula of the longitudinal relative shrinkage is as follows: sd= (R0-R)/R0 is 100%; wherein Sd is longitudinal relative shrinkage, R0 is the rotating speed of the feeding traction roller set (2), and R is the rotating speed of the discharging traction roller set (4);
the calculation formula of the transverse relative shrinkage is as follows: st= (W0-W)/w0×100%; where St is the transverse relative shrinkage, where W0 is the original width of the continuously measured sample at the linear shrinkage, and W is the actual width of the continuously measured sample at the linear shrinkage after passing through the heat shrinkage apparatus (3).
6. A regenerated PETG heat shrink film based on the regenerated environmental protection polyester film production process of claims 1-5, characterized in that: the regenerated PETG heat-shrinkable film is of a three-layer composite structure and comprises a surface film layer and a core film layer clamped between the two surface film layers; the surface film layer is made of the same material, and comprises 64-98 parts by mass of PETG,0-30 parts by mass of PET and 2-6 parts by mass of slipping agent; the components of the core film layer material comprise 90-100 parts by mass of rPETG anti-aging granulating materials and 0-10 parts by mass of start-up debugging waste granulating materials, and the trimming crushing materials are added into the core film layer material along with the line.
7. The regenerated PETG heat shrink film of the regenerated environmental protection polyester film production process of claim 6, wherein the regenerated PETG heat shrink film is characterized in that: the total thickness of the regenerated PETG heat-shrinkable film is 20-50 mu m; the thickness of the surface film layer is equal and is 2-5 mu m; the longitudinal shrinkage is 1-30% and the transverse shrinkage is 50-80%.
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Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR19990009971A (en) * | 1997-07-14 | 1999-02-05 | 구광시 | Manufacturing method of polyester film which gave functionality |
JP2009131982A (en) * | 2007-11-29 | 2009-06-18 | Toyobo Co Ltd | Polyethylene terephthalate resin film and manufacturing method therefor |
CN102152585A (en) * | 2010-12-16 | 2011-08-17 | 浙江强盟实业股份有限公司 | Twistable polyester film and preparation method thereof |
CN102582189A (en) * | 2012-02-09 | 2012-07-18 | 江苏双星彩塑新材料股份有限公司 | Shrinking-proof polyethylene terephthalate (PET) laser transfer base film and method for preparing same |
CN203033520U (en) * | 2012-12-25 | 2013-07-03 | 广州鹿山新材料股份有限公司 | Film cutting equipment |
CN105606641A (en) * | 2015-12-29 | 2016-05-25 | 河南惠强新能源材料科技股份有限公司 | Online real-time monitoring system and method for monitoring heat shrinkage rate of lithium battery diaphragm |
CN108248162A (en) * | 2016-12-28 | 2018-07-06 | 天津市凯旋塑料制品有限公司 | A kind of environment friendly composite plastic film and preparation method |
CN218067725U (en) * | 2022-08-09 | 2022-12-16 | 河南达新源新材料有限公司 | Device for testing shrinkage rate of shrink film on line |
CN116834399A (en) * | 2023-06-19 | 2023-10-03 | 江苏景宏新材料科技有限公司 | UV printing polyester film for battery label and preparation method thereof |
CN117021725A (en) * | 2023-10-10 | 2023-11-10 | 河南银金达新材料股份有限公司 | Crystalline polyester heat-shrinkable film easy to recycle and preparation method thereof |
-
2023
- 2023-11-30 CN CN202311625452.4A patent/CN117301590B/en active Active
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR19990009971A (en) * | 1997-07-14 | 1999-02-05 | 구광시 | Manufacturing method of polyester film which gave functionality |
JP2009131982A (en) * | 2007-11-29 | 2009-06-18 | Toyobo Co Ltd | Polyethylene terephthalate resin film and manufacturing method therefor |
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CN102582189A (en) * | 2012-02-09 | 2012-07-18 | 江苏双星彩塑新材料股份有限公司 | Shrinking-proof polyethylene terephthalate (PET) laser transfer base film and method for preparing same |
CN203033520U (en) * | 2012-12-25 | 2013-07-03 | 广州鹿山新材料股份有限公司 | Film cutting equipment |
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CN108248162A (en) * | 2016-12-28 | 2018-07-06 | 天津市凯旋塑料制品有限公司 | A kind of environment friendly composite plastic film and preparation method |
CN218067725U (en) * | 2022-08-09 | 2022-12-16 | 河南达新源新材料有限公司 | Device for testing shrinkage rate of shrink film on line |
CN116834399A (en) * | 2023-06-19 | 2023-10-03 | 江苏景宏新材料科技有限公司 | UV printing polyester film for battery label and preparation method thereof |
CN117021725A (en) * | 2023-10-10 | 2023-11-10 | 河南银金达新材料股份有限公司 | Crystalline polyester heat-shrinkable film easy to recycle and preparation method thereof |
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