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CN-122008580-A - High-ductility PVC calendered film and preparation method thereof

CN122008580ACN 122008580 ACN122008580 ACN 122008580ACN-122008580-A

Abstract

The invention discloses a high-ductility PVC calendered film and a preparation method thereof. The method comprises the following steps of weighing components according to parts by weight, sequentially adding raw materials in the first step into a high-speed hot mixer, placing materials subjected to hot mixing in the third step into a cold mixer, conveying the materials subjected to cold mixing in the fourth step into a double-screw extrusion plasticizing machine, sequentially conveying the materials subjected to pre-plasticizing into a primary plastic smelting machine and a final plastic smelting machine, conveying a material sheet into a four-roller calender, conveying a rolled film to a cooling device through a traction device, and carrying out coiling, trimming and inspection on the cooled film to obtain the high-ductility PVC rolled film. PVC resin with specific polymerization degree is selected and matched with a composite plasticizing system and a calcium-zinc stabilizer, so that the compatibility of components, the processing stability, the environmental protection performance and the ductility of the film are improved.

Inventors

  • HU WEI
  • ZHANG WU
  • LI WANGYANG
  • CHEN DENGLIANG
  • ZHAO KAI
  • DUAN CHUNLAI
  • WAN HUI
  • SUN TIANLONG
  • CAO HAIXIA
  • TAN WENLONG

Assignees

  • 安徽嘉阳新材料科技有限公司

Dates

Publication Date
20260512
Application Date
20251229

Claims (9)

  1. 1. The preparation method of the high-ductility PVC calendered film is characterized by comprising the following steps of: Weighing 90-110 parts of PVC resin, 30-50 parts of DOP, 2-8 parts of epoxidized soybean oil, 1-5 parts of calcium-zinc composite stabilizer, 0.2-0.8 part of stearic acid, 0.1-0.5 part of PE wax and 1-4 parts of acrylic ester processing aid according to parts by weight; Sequentially adding the raw materials in the first step into a high-speed heat mixer, stirring at a speed of 500-800r/min for 3-5min, stirring at a speed of 1200-1500r/min for 8-12min, and controlling the temperature of the materials to 80-100 ℃ until the resin is fully swelled; Step three, placing the materials after the hot mixing in the step two into a cold mixer, stirring and cooling to about 50 ℃ at the speed of 800-1000r/min to obtain loose granular materials; step four, feeding the materials subjected to the cold mixing in the step three into a double-screw extrusion plasticizing machine, and pre-plasticizing the materials at the screw rotation speed of 30-50r/min by adopting sectional temperature control, wherein the temperature of the feeding section is 140-145 ℃, the temperature of the compression section is 145-155 ℃ and the temperature of the metering section is 155-160 ℃, and the plasticizing degree is more than or equal to 95%; Sequentially feeding the pre-plasticized material into a primary plastic refining machine and a final plastic refining machine, wherein the temperature of a roller of the primary plastic refining machine is 150-155 ℃, the roller speed ratio is 1:1.2-1:1.5, and the plastic refining is 3-5min, the temperature of a roller of the final plastic refining machine is 155-160 ℃, the roller speed ratio is 1:1.5-1:2.0, and the plastic refining is 2-4min, so that a material sheet with the thickness of 2-5mm is obtained; Step six, feeding the material sheet into a four-roller calender, wherein the temperature of the four rollers is 160-165 ℃ for an upper roller, 165-170 ℃ for a middle roller, 160-165 ℃ for a lower roller and 155-160 ℃ for a bottom roller in sequence, the roller speed ratio is 1:1.2:1.5:1.8, the roller gap is adjusted to the target film thickness, and the material sheet is subjected to calendaring molding; drawing the rolled film to a cooling device through a drawing device, adopting three sections of cooling, and cooling to the film shrinkage rate less than or equal to 1% in a slow cooling area of 80-100 ℃, a quenching area of 20-30 ℃ and a constant temperature area of 25-30 ℃; And step eight, coiling the cooled film, wherein the coiling tension is 3-8N/m, trimming and checking after coiling to obtain the high-ductility PVC calendered film.
  2. 2. The preparation method of the high-ductility PVC calendered film according to claim 1, wherein in the first step, the calcium-zinc composite stabilizer has a calcium-zinc molar ratio of 3:1-5:1, and further comprises 0.5-1.0 part of phosphite auxiliary stabilizer, wherein the PVC resin is suspension PVC resin with an average polymerization degree of 1000-1200, and the epoxy value of the epoxidized soybean oil is more than or equal to 6.0%.
  3. 3. The method for preparing the high-ductility PVC calendered film according to claim 1, wherein the gap between the rollers at the feeding end of the four-roller calender in the step six is 2-3mm, the gap between the discharging end of the four-roller calender is consistent with the thickness of a target film, the error is +/-0.01 mm, and an online thickness detector is adopted to monitor the film thickness in real time.
  4. 4. The method for producing a high-ductility PVC calendered film according to claim 1, wherein the antistatic agent is sprayed on the film surface in the coiling process in the step eight in an amount of 0.05 to 0.1% by weight, and the trimming width is 5 to 10mm.
  5. 5. The method for preparing the high-ductility PVC calendered film according to claim 1, wherein in the first step, the components comprise 90 parts by weight of PVC resin, 30 parts by weight of DOP, 2 parts by weight of epoxidized soybean oil, 1 part by weight of calcium-zinc composite stabilizer, 0.2 part by weight of stearic acid, 0.1 part by weight of PE wax and 1 part by weight of acrylate processing aid.
  6. 6. The method for preparing the high-ductility PVC calendered film according to claim 1, wherein in the first step, the components comprise, by weight, 100 parts of PVC resin, 40 parts of DOP, 4 parts of epoxidized soybean oil, 3 parts of calcium-zinc composite stabilizer, 0.4 part of stearic acid, 0.3 part of PE wax and 2 parts of acrylate processing aid.
  7. 7. The method for preparing the high-ductility PVC calendered film according to claim 1, wherein in the first step, the components comprise 110 parts by weight of PVC resin, 50 parts by weight of DOP, 6 parts by weight of epoxidized soybean oil, 5 parts by weight of calcium-zinc composite stabilizer, 0.6 part by weight of stearic acid, 0.5 part by weight of PE wax and 3 parts by weight of acrylate processing aid.
  8. 8. The method for preparing the high-ductility PVC calendered film according to claim 1, wherein in the first step, the components comprise, by weight, 95 parts of PVC resin, 35 parts of DOP, 8 parts of epoxidized soybean oil, 2 parts of calcium-zinc composite stabilizer, 0.8 part of stearic acid, 0.2 part of PE wax and 4 parts of acrylate processing aid.
  9. 9. The high-ductility PVC calendered film is characterized in that the PVC calendered film is prepared by the preparation method of any one of claims 1-8, and has a thickness of 0.05-0.5mm, an elongation at break of more than or equal to 300%, a tensile strength of more than or equal to 15MPa and a shrinkage of less than or equal to 1%.

Description

High-ductility PVC calendered film and preparation method thereof Technical Field The invention relates to the field of PVC (polyvinyl chloride) calendered film preparation, in particular to a high-ductility PVC calendered film and a preparation method thereof. Background The PVC calendered film has low cost, good processability and excellent comprehensive performance, and is widely applied to the fields of packaging, building materials, light industry and the like. However, in the existing PVC calendered film preparation process, the problems of insufficient ductility, easiness in cracking, poor processing stability and the like often exist, and the application of the PVC calendered film in the high-end field is limited; in the prior art, PVC resin is poor in thermal stability and easy to degrade during processing, so that the mechanical property of the film is reduced, the ductility is influenced, in addition, the traditional stabilizer is mostly lead salts, although the thermal stability effect is good, the traditional stabilizer has hidden danger in environment protection and does not meet the green production requirement, and when the environment-friendly stabilizer is applied, the processing window is narrow and the film is easy to generate defects due to improper formula collocation, so that the problem needs to be solved. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides a high-ductility PVC calendered film and a preparation method thereof, wherein PVC resin with specific polymerization degree is selected and matched with a composite plasticizing system and a calcium-zinc stabilizer, so that the component compatibility, the processing stability, the environmental protection property of a film material and the ductility are improved. The high-low speed sectional mixing, double screw sectional temperature control and other processes are adopted, so that the materials are fully plasticized, the uniformity of the material sheets is ensured, and the performance of the calendaring film is improved. Four-roller calendering is accurate to control temperature, roller speed ratio matching and three-stage cooling, reduces shrinkage, reasonably rolls up tension control, ensures that the film material is smooth, stable in size and few in defects. In order to achieve the above purpose, the present invention adopts the following technical scheme: The preparation method of the high-ductility PVC calendered film comprises the following steps of: Weighing 90-110 parts of PVC resin, 30-50 parts of DOP, 2-8 parts of epoxidized soybean oil, 1-5 parts of calcium-zinc composite stabilizer, 0.2-0.8 part of stearic acid, 0.1-0.5 part of PE wax and 1-4 parts of acrylic ester processing aid according to parts by weight; Sequentially adding the raw materials in the first step into a high-speed heat mixer, firstly stirring at a low speed of 500-800r/min for 3-5min, then stirring at a high speed of 1200-1500r/min for 8-12min, and controlling the temperature of the materials to be increased to 80-100 ℃ until the resin is fully swelled; step three, placing the materials after the hot mixing in the step two into a cold mixer, stirring and cooling to about 50 ℃ at 800-1000r/min to obtain loose granular materials; step four, feeding the materials subjected to the cold mixing in the step three into a double-screw extrusion plasticizing machine, and pre-plasticizing the materials at the screw rotation speed of 30-50r/min by adopting sectional temperature control, wherein the temperature of the feeding section is 140-145 ℃, the temperature of the compression section is 145-155 ℃ and the temperature of the metering section is 155-160 ℃, and the plasticizing degree is more than or equal to 95%; Sequentially feeding the pre-plasticized material into a primary plastic refining machine and a final plastic refining machine, wherein the temperature of a roller of the primary plastic refining machine is 150-155 ℃, the roller speed ratio is 1:1.2-1:1.5, and the plastic refining is 3-5min, the temperature of a roller of the final plastic refining machine is 155-160 ℃, the roller speed ratio is 1:1.5-1:2.0, and the plastic refining is 2-4min, so that a material sheet with the thickness of 2-5mm is obtained; Step six, feeding the material sheet into a four-roller calender, wherein the temperature of the four rollers is 160-165 ℃ for an upper roller, 165-170 ℃ for a middle roller, 160-165 ℃ for a lower roller and 155-160 ℃ for a bottom roller in sequence, the roller speed ratio is 1:1.2:1.5:1.8, the roller gap is adjusted to the target film thickness, and the material sheet is subjected to calendaring molding; drawing the rolled film to a cooling device through a drawing device, adopting three sections of cooling, and cooling to the film shrinkage rate less than or equal to 1% in a slow cooling area of 80-100 ℃, a quenching area of 20-30 ℃ and a constant temperature area of 25-30 ℃; And step eight, coilin