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CN-121991428-A - Low-temperature-resistant plastic for preparing special cucurbit bubble film for cold chain and preparation method thereof

CN121991428ACN 121991428 ACN121991428 ACN 121991428ACN-121991428-A

Abstract

The invention provides a low temperature resistant plastic for preparing a special calabash bubble film for a cold chain and a preparation method thereof, wherein the preparation raw materials comprise, by weight, 60-75 parts of metallocene linear low density polyethylene, 15-25 parts of ethylene-octene copolymer elastomer, 3-8 parts of compatibilizer reinforcing modifier, 2-6 parts of barrier antibacterial function filler, 5-10 parts of calcium sulfate whisker, 2-5 parts of maleic anhydride grafted polyethylene, 0.5-1.5 parts of composite lubricant, 0.5-1.5 parts of antistatic agent, 0.3-0.8 parts of antioxidant and 0.3-0.8 parts of opening agent. The low-temperature-resistant plastic provided by the invention takes metallocene linear low-density polyethylene as a matrix, integrates the low-temperature toughness, rigidity and puncture resistance of the material, has barrier antibacterial, antistatic and anti-aging properties, and can meet the processing molding and practical application requirements of the special calabash bubble film for the cold chain.

Inventors

  • Mao Longlong
  • ZHANG JINLING

Assignees

  • 浙江东方万象新材料有限公司

Dates

Publication Date
20260508
Application Date
20260409

Claims (9)

  1. 1. The low temperature resistant plastic for preparing the special calabash bubble film for the cold chain is characterized by comprising, by weight, 60-75 parts of metallocene linear low density polyethylene, 15-25 parts of ethylene-octene copolymer elastomer, 3-8 parts of compatibilizer reinforcing modifier, 2-6 parts of barrier antibacterial function filler, 5-10 parts of calcium sulfate whisker, 2-5 parts of maleic anhydride grafted polyethylene, 0.5-1.5 parts of composite lubricant, 0.5-1.5 parts of antistatic agent, 0.3-0.8 parts of antioxidant and 0.3-0.8 part of opening agent.
  2. 2. The low temperature resistant plastic for preparing the special cucurbit foam film for the cold chain of claim 1, wherein the composite lubricant is prepared by compounding erucamide and polyethylene wax according to a mass ratio of 1.8:1-2.2:1, the antistatic agent is an ethoxylated alkylamine antistatic agent, and the antioxidant is one or more of an antioxidant 1010, an antioxidant 168 and an antioxidant 1076.
  3. 3. The low-temperature-resistant plastic for preparing the special calabash bubble film for the cold chain according to claim 1, wherein the compatibilizing and reinforcing modifier is a polyethyleneimine functionalized graphene oxide grafted ethylene-octene copolymer, the number average molecular weight of the copolymer is 20000-28000g/mol, the barrier antibacterial functional filler is silver-loaded mesoporous silica and magnesium aluminum hydrotalcite physical composite powder, the silver loading amount of the filler is 2-4%, the length of the calcium sulfate whisker is 10-25 mu m, the diameter of the calcium sulfate whisker is 0.5-1.0 mu m, the grafting rate of the maleic anhydride grafted polyethylene is 0.8-1.2%, the opening agent is silica, and the average particle size of the opening agent is 2.0-4.0 mu m.
  4. 4. The low temperature resistant plastic for preparing the special calabash bubble film for the cold chain, which is disclosed in claim 1, is characterized in that the preparation raw materials of the compatibilization reinforcing modifier comprise, by weight, 1-2 parts of graphene oxide, 1.5-3 parts of branched polyethylenimine, 15-25 parts of maleic anhydride grafted ethylene-octene copolymer, 50-100 parts of anhydrous toluene, 0.5-1.0 part of dicyclohexylcarbodiimide, wherein the thickness of a lamellar layer of the graphene oxide is 1-5nm, the number average molecular weight of the branched polyethylenimine is 600-1000g/mol, and the grafting rate of the maleic anhydride grafted ethylene-octene copolymer is 0.8% -1.5%.
  5. 5. The low temperature resistant plastic for preparing a cucurbit bubble film special for a cold chain according to claim 4, wherein the preparation method of the compatibilizing and reinforcing modifier comprises the following steps: 1) Adding graphene oxide and branched polyethyleneimine into a reaction vessel, adding dicyclohexylcarbodiimide of which the weight is half that of the dicyclohexylcarbodiimide, taking anhydrous toluene accounting for 1/3-1/2 of the total weight of the anhydrous toluene as a dispersion medium, performing ultrasonic dispersion for 20-40min under the conditions of power of 200-300W and frequency of 35-45kHz, stirring in an oil bath at 70-80 ℃ for reaction for 3-5h at the rotating speed of 150-250r/min, centrifugally separating a reaction product at 3000-5000r/min for 5-10min, washing a precipitate with absolute ethyl alcohol for 2-4 times, and then performing vacuum drying for 8-14h under the conditions of 60-70 ℃ and vacuum degree of-0.08 MPa to-0.095 MPa to obtain polyethyleneimine functionalized graphene oxide; 2) Adding polyethyleneimine functionalized graphene oxide into residual anhydrous toluene under the protection of nitrogen, performing ultrasonic dispersion for 20-40min under the conditions of power of 200-300W and frequency of 35-45kHz, adding maleic anhydride grafted ethylene-octene copolymer and residual dicyclohexylcarbodiimide, stirring at the speed of 100-200r/min for reaction for 4-6h at the temperature of 75-85 ℃, centrifugally separating reaction products at the speed of 3000-5000r/min for 5-10min, washing precipitate with absolute ethyl alcohol for 2-4 times, and then performing vacuum drying for 10-14h under the conditions of 70-80 ℃ and vacuum degree of-0.08 MPa to-0.095 MPa to obtain the compatibilization reinforcing modifier.
  6. 6. The low temperature resistant plastic for preparing the special calabash bubble film for the cold chain according to claim 1, wherein the preparation raw materials of the barrier antibacterial function filler comprise, by weight, 8-12 parts of mesoporous silica, 8-12 parts of magnesium aluminum hydrotalcite, 2.5-3.5 parts of 3-aminopropyl triethoxysilane, 0.3-0.5 part of silver nitrate, 0.6-1.0 part of ascorbic acid, 150-250 parts of absolute ethyl alcohol and 50-80 parts of deionized water.
  7. 7. The low temperature resistant plastic for preparing a cold chain dedicated cucurbit bubble film according to claim 6, wherein the average particle size of the mesoporous silica is 80-120nm, the pore diameter is 3-5nm, the average particle size of the magnesium aluminum hydrotalcite is 1-3 μm, and the molar ratio of magnesium ions to aluminum ions is 1.8:1-2.2:1.
  8. 8. A method for preparing the low temperature resistant plastic for preparing the cucurbit foam film special for the cold chain according to any one of claims 1 to 7, which is characterized by comprising the following steps: s1, pretreatment of raw materials: Placing the calcium sulfate whisker and the blocking antibacterial function filler into a blast drying oven at 105-115 ℃ for drying for 3-5h; Drying metallocene linear low density polyethylene and ethylene-octene copolymer elastomer at 75-85 ℃ for 2-4h; drying the compatibilization reinforcing modifier for 1.5-2.5h under the conditions of 55-65 ℃ and vacuum degree of-0.08 MPa to-0.095 MPa; S2, mixing by a two-step method: Adding the dried metallocene linear low-density polyethylene, the ethylene-octene copolymer elastomer, the compatibilization reinforcing modifier, the maleic anhydride grafted polyethylene, the composite lubricant and the antioxidant into a high-speed mixer, and mixing for 8-12min at the rotating speed of 800-1000r/min to obtain a main mixture; Adding dried calcium sulfate whisker, a blocking and antibacterial functional filler, an antistatic agent and an opening agent into the main mixture, heating the mixture to 60-70 ℃, and mixing for 10-15min at a rotating speed of 600-800r/min to obtain a uniform blending material; S3, feeding the blending material obtained in the step S2 into a homodromous parallel double-screw extruder for melt blending and extrusion, wherein the temperature of the extruder is set to be 140-145 ℃ in a first area, 150-155 ℃ in a second area, 160-165 ℃ in a third area, 165-170 ℃ in a fourth area, 163-167 ℃ in a fifth area and 160-165 ℃ in a head, the rotating speed of the screw is 200-280r/min, the retention time of the material is 2-4min, a vacuum exhaust port is arranged behind a third machine barrel section, and the vacuum degree is maintained to be-0.07 MPa to-0.09 MPa; s4, cooling the material strips extruded in the step S3 through a water tank at the temperature of 25-35 ℃, cutting into uniform particles with the length of 2-3mm, carrying out forced air drying in a forced air drying box at the temperature of 60-70 ℃ for 2-3h, and sealing and packaging to obtain the low-temperature-resistant plastic particles.
  9. 9. The method for preparing a low temperature resistant plastic for preparing a cold chain dedicated cucurbit bubble film according to claim 8, wherein in the step S3, the length-diameter ratio of the co-rotating parallel twin-screw extruder is 40:1-48:1.

Description

Low-temperature-resistant plastic for preparing special cucurbit bubble film for cold chain and preparation method thereof Technical Field The invention relates to the technical field of polyolefin modified materials, in particular to a low-temperature-resistant plastic for preparing a special cucurbit bubble film for a cold chain and a preparation method thereof. Background The rapid development of the cold chain logistics industry brings higher requirements on the low temperature resistance of packaging materials, and the cucurbit bubble film is used as a common cold chain buffer packaging material, and the low temperature resistance of base material plastics directly determines the protection effect and the service life of the packaging. At present, a common polyolefin material is mostly adopted as a bubble film base material for cold chain packaging, and a small amount of low temperature resistant modified components are added into part of products, wherein metallocene polyolefin is widely used as a modified base material of low temperature resistant plastics due to excellent low temperature toughness and mechanical stability, but the modification mode in the prior art is single, and the requirement of the bubble film on comprehensive use performance under a cold chain environment is difficult to meet. The low-temperature-resistant plastic for preparing the cold chain block foam film in the prior art generally has the problem that low-temperature toughness and rigidity are difficult to be compatible, the conventional modification means can improve the low-temperature impact resistance of the material to a certain extent, but can obviously reduce the rigidity, the dimensional stability and the puncture resistance of the material, the use requirements of the block foam film on buffering protection and structural stability in the cold chain transportation process cannot be met, meanwhile, the interface compatible components and functional fillers are not reasonably introduced into a part of modification system, so that the interface binding force of the material is poor, the melt strength is insufficient, the unstable molding condition easily occurs in the processing process, and the phenomena of electrostatic adsorption or the blocking of the block foam film easily occur in the prepared block foam film, so that the use performance and the application reliability of the cold chain package are further reduced. Disclosure of Invention Aiming at the problems in the prior art, the invention provides the low-temperature-resistant plastic for preparing the special cucurbit foaming film for the cold chain and the preparation method thereof, so as to improve the low-temperature toughness, rigidity and puncture resistance of the low-temperature-resistant plastic, and endow the material with excellent barrier antibacterial, antistatic and anti-aging properties, thereby meeting the processing and molding requirements and the actual use performance requirements of the special cucurbit foaming film for the cold chain. In order to achieve the above purpose, the invention is realized by the following technical scheme: The invention discloses a low-temperature-resistant plastic for preparing a special calabash bubble film for a cold chain, which comprises, by weight, 60-75 parts of metallocene linear low-density polyethylene, 15-25 parts of ethylene-octene copolymer elastomer, 3-8 parts of compatibilizing and reinforcing modifier, 2-6 parts of barrier antibacterial function filler, 5-10 parts of calcium sulfate whisker, 2-5 parts of maleic anhydride grafted polyethylene, 0.5-1.5 parts of composite lubricant, 0.5-1.5 parts of antistatic agent, 0.3-0.8 parts of antioxidant and 0.3-0.8 parts of opening agent. The technical scheme is adopted, metallocene linear low-density polyethylene is used as a matrix of the low-temperature resistant plastic, basic mechanical strength and optical performance are provided for materials, ethylene-octene copolymer elastomer is used as a low-temperature toughening component, low-temperature impact toughness of the materials can be effectively improved, a compatibilization reinforcing modifier can improve interfacial bonding force of the materials, melt strength is improved, an antibacterial function filler is blocked, gas permeability of the materials can be reduced, an antibacterial effect is achieved, hydroxyl groups of calcium sulfate whiskers and anhydride groups of maleic anhydride grafted polyethylene form hydrogen bonding effect, the calcium sulfate whiskers are uniformly dispersed in the polyolefin matrix and form a one-dimensional rigid skeleton, rigidity, dimensional stability and puncture resistance of the materials are cooperatively improved, the maleic anhydride grafted polyethylene can improve interfacial compatibility of the polar filler and the nonpolar polyolefin matrix, a composite lubricant can reduce friction between melt and equipment in a material melt processing process