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CN-122011589-A - Flame-retardant waterproof packaging film material and preparation method thereof

CN122011589ACN 122011589 ACN122011589 ACN 122011589ACN-122011589-A

Abstract

The invention discloses a flame-retardant waterproof packaging film material and a preparation method thereof, and relates to the technical field of packaging materials. The packaging film material comprises, by weight, 100 parts of polypropylene, 10-15 parts of modified expanded vermiculite, 0.5 part of dicumyl peroxide and 15 parts of maleic anhydride grafted polypropylene, wherein the invention selects amino trimethylene phosphonic acid and vinyl-terminated polyethylene glycol modified expanded vermiculite. The amino trimethylene phosphonic acid is complexed with magnesium and aluminum ions between the expanded vermiculite layers by means of phosphonic acid groups, so that the flame retardant elements phosphorus and nitrogen are introduced into the surface of the vermiculite layer, and long chain molecules of vinyl-terminated polyethylene glycol are used for stretching the layers, improving the compatibility with a matrix, introducing vinyl on the surface of the long chain molecules, and then being chemically combined with the resin matrix. The preparation process of the invention is in one step, the whole flow is simple, and the strength, flame retardance and waterproof performance of the packaging film are obviously improved.

Inventors

  • XU JUN
  • ZHANG WEIWEI
  • MIAO YAJUN
  • ZHANG JIAN

Assignees

  • 南通十灵智能科技有限公司

Dates

Publication Date
20260512
Application Date
20260320

Claims (10)

  1. 1. The flame-retardant waterproof packaging film is characterized by comprising, by weight, 100 parts of polypropylene, 10-15 parts of modified expanded vermiculite, 0.5 part of dicumyl peroxide and 15 parts of maleic anhydride grafted polypropylene; the preparation method of the modified expanded vermiculite comprises the steps of preparing an aqueous solution from amino trimethylene phosphonic acid, adjusting the pH value to 4.5 by using a sodium hydroxide solution, adding the sodium expanded vermiculite into the aqueous solution, stirring for 2 hours in a water bath at 60 ℃, then adding vinyl-terminated polyethylene glycol into a reaction system, continuously stirring for 6 hours at 80 ℃, cooling to room temperature after the reaction is finished, carrying out suction filtration, washing a filter cake by using absolute ethyl alcohol for three times, and drying the filter cake for 24 hours to obtain the modified expanded vermiculite.
  2. 2. The flame-retardant and waterproof packaging film material according to claim 1, wherein the concentration of the amino trimethylene phosphonic acid aqueous solution is 10g/L.
  3. 3. The flame-retardant waterproof packaging film according to claim 1, wherein the mass fraction of the sodium hydroxide solution is 10%.
  4. 4. The flame-retardant and waterproof packaging film material according to claim 1, wherein the mass ratio of the sodified expanded vermiculite to the aminotrimethylene phosphonic acid is 1:0.2-1:0.3.
  5. 5. The flame-retardant and waterproof packaging film material according to claim 1, wherein the number average molecular weight of the vinyl-terminated polyethylene glycol is 2000-4000.
  6. 6. The flame-retardant waterproof packaging film material according to claim 1, wherein the addition amount of the vinyl-terminated polyethylene glycol is 20-30% of the mass of the sodium-modified expanded vermiculite.
  7. 7. The flame-retardant waterproof packaging film material according to claim 1 is characterized in that the preparation method of the sodified expanded vermiculite is that the expanded vermiculite is crushed and then passes through a 300-mesh sieve, the undersize is added into a sodium chloride solution with the concentration of 1mol/L, the solid-liquid mass ratio of the expanded vermiculite to the sodium chloride solution is 1:15-1:20, the mixture is stirred and reacted for 6 hours in a constant-temperature water bath at 80 ℃, the mixture is filtered after the reaction is finished, the filter cake is washed by deionized water until no chloridion is detected, and the filter cake is dried to constant weight, so that the sodified expanded vermiculite is obtained.
  8. 8. The flame-retardant waterproof packaging film material according to claim 1 is characterized in that the packaging film material is prepared by adding polypropylene, modified expanded vermiculite, dicumyl peroxide and maleic anhydride grafted polypropylene into a high-speed mixer to be mixed for 10min according to parts by weight, adding the mixed materials into a double-screw extruder to be melt, blending and extruding, obtaining cylindrical polypropylene particles with the diameter of 2-4mm and the length of 3-5mm after water cooling, granulating and drying the extruded material strips, adding the polypropylene particles into a single-screw extrusion film blowing machine to be extruded, and winding the polypropylene particles after film bubble stabilization to obtain the polypropylene packaging film material.
  9. 9. The flame-retardant waterproof packaging film according to claim 8 is characterized in that 100 parts of polypropylene, 3-8 parts of maleic anhydride and 0.3-0.8 part of dicumyl peroxide are added into a high-speed mixer to be mixed for 5-10min, the rotating speed of the mixer is 300-500 rpm, the mixed materials are added into a double-screw extruder to be subjected to melt grafting reaction, and the extruded material strips are subjected to water cooling, granulating and drying to obtain the maleic anhydride grafted polypropylene.
  10. 10. A fire-retardant waterproof packaging film according to claim 8, wherein the thickness of the packaging film is preferably 50 μm, and the packaging film can be customized according to different requirements.

Description

Flame-retardant waterproof packaging film material and preparation method thereof Technical Field The invention relates to the technical field of packaging materials, in particular to a flame-retardant waterproof packaging film material and a preparation method thereof. Background In the prior art, vermiculite is regarded as a potential filler for improving the flame retardant property and the barrier property of polyolefin materials due to the natural layered structure and good thermal stability. However, vermiculite surface is rich in hydroxyl groups and shows hydrophilicity, and is lack of compatibility with hydrophobic polypropylene, polyethylene and other matrix materials, so that the vermiculite is difficult to uniformly disperse when directly added, agglomerates are easily formed in the matrix, physical barrier effect of a lamellar structure of the vermiculite cannot be exerted, and the vermiculite becomes a stress concentration point inside the material, so that mechanical properties are reduced. To solve this problem, it is generally necessary to carry out an organic modification treatment on vermiculite. However, the existing modification method generally has the problems of complicated steps, long flow and great control difficulty. Even though the modified vermiculite is subjected to multi-step treatment, the interface combination of the modified vermiculite and the polyolefin matrix is still not ideal, the sheet layer cannot be fully peeled off, and the dispersion state and the interface anchoring strength of the modified vermiculite in the matrix are difficult to meet the actual application demands. In addition, the commonly used modifier only plays a role in compatibilization, does not have flame retardant elements, and vermiculite only exists as a physical barrier in materials, so that the flame retardant efficiency is limited, and the use requirement can be met only by compounding the vermiculite with other flame retardants, so that the complexity of the formula design is further increased. More importantly, because the interface is not firmly combined, microscopic gaps are easy to form between the filler and the matrix, and water molecules and oxygen can permeate along the interface, so that the barrier property of the material is weakened. Therefore, how to simplify the modification process, synchronously improve the interface compatibility of vermiculite and polyolefin, endow the vermiculite with chemical flame retardant capability and keep the original mechanical properties of the material becomes a problem to be solved in the current packaging film field. Disclosure of Invention The invention aims to provide a flame-retardant waterproof packaging film material and a preparation method thereof, which are used for solving the problems in the prior art. In order to solve the technical problems, the invention provides the following technical scheme that the flame-retardant waterproof packaging film material comprises, by weight, 100 parts of polypropylene, 10-15 parts of modified expanded vermiculite, 0.5 part of dicumyl peroxide and 15 parts of maleic anhydride grafted polypropylene; the preparation method of the modified expanded vermiculite comprises the steps of preparing an aqueous solution from amino trimethylene phosphonic acid, adjusting the pH value to 4.5 by using a sodium hydroxide solution, adding the sodium expanded vermiculite into the aqueous solution, stirring for 2 hours in a water bath at 60 ℃, then adding vinyl-terminated polyethylene glycol into a reaction system, continuously stirring for 6 hours at 80 ℃, cooling to room temperature after the reaction is finished, carrying out suction filtration, washing a filter cake by using absolute ethyl alcohol for three times, and drying the filter cake for 24 hours to obtain the modified expanded vermiculite. Further, the concentration of the aqueous aminotrimethylene phosphonic acid solution is 10g/L. Further, the mass fraction of the sodium hydroxide solution is 10%. Further, the mass ratio of the sodium expanded vermiculite to the amino trimethylene phosphonic acid is 1:0.2-1:0.3. Further, the number average molecular weight of the vinyl-terminated polyethylene glycol is 2000-4000. Further, the addition amount of the vinyl-terminated polyethylene glycol is 20-30% of the mass of the sodium-modified expanded vermiculite. Further, the preparation method of the sodium expanded vermiculite comprises the steps of crushing the expanded vermiculite, sieving the crushed expanded vermiculite with a 300-mesh sieve, adding the sieved substance into a sodium chloride solution with the concentration of 1mol/L, stirring the mixture in a constant-temperature water bath at the temperature of 80 ℃ for reaction for 6 hours, filtering the mixture after the reaction is finished, washing a filter cake with deionized water until no chloride ions are detected, and drying the filter cake to constant weight to obtain the sodium expanded vermiculite. Th