CN112608590A - Flame-retardant plastic film and preparation method thereof - Google Patents

Abstract

The invention discloses a flame-retardant plastic film which is prepared from the following raw materials in parts by weight: 50-60 parts of polyurethane resin, 19-25 parts of poly (butylene succinate), 2-3 parts of flame-retardant active matter, 4-6 parts of filler, 1.5-2 parts of silane coupling agent, 0.8-1 part of antioxidant and 1-2 parts of lubricant; the invention also discloses a preparation method of the plastic film, which comprises the processes of pretreatment, blending and granulation. According to the invention, the flame-retardant active substance and the filler are added into the film raw material, so that the mechanical property of the plastic film can be enhanced, the flame-retardant active substance and the filler have a synergistic effect, the flame-retardant effect of the plastic film is further enhanced, the obtained plastic film has good flame-retardant property on the basis of higher mechanical property, the use safety of the plastic film can be effectively improved, and the application range of the plastic film is enlarged.

Description

Flame-retardant plastic film and preparation method thereof

Technical Field

The invention belongs to the field of plastic film processing, and particularly relates to a flame-retardant plastic film and a preparation method thereof.

Background

Plastic films are one of the most important flexible packaging materials, and have various kinds and different characteristics, and the use of the plastic films is different according to different characteristics of the films. Polyethylene films, polypropylene films, polyvinyl chloride films, polystyrene films, polyvinylidene chloride films, ethylene-vinyl acetate copolymer films, polyvinyl alcohol films, nylon films, and the like are relatively common plastic films. Many existing plastic films are poor in flame retardant property, easy to burn in case of fire and not safe.

Chinese patent CN201510216597.8 discloses a flame-retardant plastic, which is prepared from the following substances in parts by weight: 40-50 parts of plastic, 15-25 parts of filler, 10-20 parts of melamine cyanurate, 5-10 parts of molybdenum trioxide, 5-10 parts of ammonium polyphosphate, 10-20 parts of polybutylene terephthalate, 15-30 parts of composite flame retardant, 10-20 parts of ferric oxide and 5-10 parts of auxiliary agent. However, the plastic disclosed by the patent is high in manufacturing cost, high in density and heavy in use, is not suitable for being popularized in a large number to be used as a common multipurpose flame-retardant film, has the defects of easy agglomeration of flame retardant components and poor compatibility with a polymer matrix, is difficult to disperse uniformly in the plastic film, and ensures that the flame retardant property of the plastic film still cannot meet the use requirement.

Disclosure of Invention

The invention aims to provide a flame-retardant plastic film and a preparation method thereof, wherein a flame-retardant active substance and a filler are added into a film raw material, so that the mechanical property of the plastic film can be enhanced, the flame-retardant active substance and the filler have a synergistic effect, the flame-retardant effect of the plastic film is further enhanced, and the obtained plastic film has good flame-retardant property on the basis of higher mechanical property, so that the use safety of the plastic film can be effectively improved, and the application range of the plastic film is enlarged.

The purpose of the invention can be realized by the following technical scheme:

the flame-retardant plastic film is prepared from the following raw materials in parts by weight: 50-60 parts of polyurethane resin, 19-25 parts of poly (butylene succinate), 2-3 parts of flame-retardant active matter, 4-6 parts of filler, 1.5-2 parts of silane coupling agent, 0.8-1 part of antioxidant and 1-2 parts of lubricant;

the plastic film is prepared by the following steps:

firstly, putting polyurethane resin and poly butylene succinate into a vacuum drying oven at 50-60 ℃ for drying for 12-14h to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer together, and stirring and mixing 22-25min at 8000r/min to prepare a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 165-175 ℃, and the plastic particles are subjected to extrusion and film blowing by a single-screw extruder to obtain the plastic film.

Further, the antioxidant is antioxidant 1010, antioxidant 300 or antioxidant 1076.

Further, the filler is a composite of the Si C whisker, the trachelospermi nanotube, the wollastonite powder and the glass fiber, and the mass ratio of the Si C whisker to the trachelospermi nanotube to the wollastonite powder to the glass fiber is 10:4-5:3-4: 5-6.

Further, the lubricant is polyethylene wax or silicone oil.

Further, the flame retardant active is prepared by the following method:

a1, dissolving polybutadiene in toluene, heating to 88-90 ℃ under stirring, stirring at constant temperature for 15-20min, cooling, adding acetic acid when the temperature is reduced to 38-40 ℃, adding aqueous hydrogen peroxide after the temperature is reduced to room temperature, and stirring at 200r/min for reaction for 8-9h at room temperature to obtain a mixed solution;

a2, pouring the mixed solution obtained in the step A1 into a separating funnel, adding distilled water for separating, continuously separating for 4-5 times, adding absolute ethyl alcohol into the reaction solution to separate out a product, and fully drying the separated product to obtain an intermediate;

a3, adding the intermediate into xylene, heating and stirring to dissolve the intermediate, adding hydroxymethyl phenylphosphinic acid, heating to 120 ℃ under stirring, continuously stirring and reacting for 9-10h at the constant temperature of 120 ℃ under 116 ℃ and rotationally steaming, and drying the product in a vacuum drying box at 70 ℃ to constant weight to obtain the flame-retardant active substance.

Further, the mass fraction of the aqueous hydrogen peroxide solution in the step a1 is 40%; the dosage ratio of the polybutadiene, the toluene, the acetic acid and the aqueous hydrogen peroxide solution is 1g:8-10mL:4-5mL:6-8 mL.

Furthermore, the dosage ratio of the intermediate, the xylene and the hydroxymethylphenylphosphinic acid in the step A3 is 1g to 35-45mL to 0.5-0.7 g.

A preparation method of a flame-retardant plastic film comprises the following steps:

firstly, putting polyurethane resin and poly butylene succinate into a vacuum drying oven at 50-60 ℃ for drying for 12-14h to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer together, and stirring and mixing 22-25min at 8000r/min to prepare a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 165-175 ℃, and the plastic particles are subjected to extrusion and film blowing by a single-screw extruder to obtain the plastic film.

The invention has the beneficial effects that:

in the invention, a self-made flame retardant active substance is added into a film, in the preparation process of the flame retardant active substance, carbon-carbon double bonds on a polybutadiene molecular chain generate epoxy groups under the oxidation of hydrogen peroxide, and the epoxy groups and-OH connected with C on hydroxymethylphenylphosphinic acid molecules generate ring-opening reaction, so that the hydroxymethylphenylphosphinic acid molecules are grafted on side chains of the polybutadiene molecules to form a macromolecular flame retardant active substance; the polymer type flame-retardant active substance has good compatibility with the polymer matrix, so that the polymer type flame-retardant active substance is uniformly distributed in the polymer matrix, and the flame-retardant effect is better exerted;

the film is added with the filler, the filler is a compound of SiC whiskers, the trachelospermi nanotubes, wollastonite powder and glass fibers, and the mass ratio of the SiC whiskers to the trachelospermi nanotubes to the wollastonite powder to the glass fibers is 10:4-5:3-4: 5-6; the pyrochlore nanotube and wollastonite powder of the filler contain Si-O bonds and Al-O bonds, when the filler and the flame-retardant active substance are compounded for use, the silicon-phosphorus synergistic effect can further promote the carbon formation of a polymer matrix, the filler and the flame-retardant active substance react to generate silicoaluminophosphate in the combustion process, and the silicoaluminophosphate can promote the formation of phosphoric acid and enhance the oxidation, dehydration, crosslinking and carbonization processes, so that the surface of residual carbon is more compact, and a more compact carbon layer not only can play a role in heat insulation, but also can reduce the generation amount of combustible gas; the Si C whiskers and the glass fibers contained in the filler can be filled in the pores of the film to improve the mechanical property of the film, and in addition, the silane coupling agent can promote the uniform dispersion of the filler in the plastic film and play the role of reinforcement and synergistic flame retardance of the filler;

according to the invention, the flame-retardant active substance and the filler are added into the film raw material, so that the mechanical property of the plastic film can be enhanced, the flame-retardant active substance and the filler have a synergistic effect, the flame-retardant effect of the plastic film is further enhanced, the obtained plastic film has good flame-retardant property on the basis of higher mechanical property, the use safety of the plastic film can be effectively improved, and the application range of the plastic film is enlarged.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The flame-retardant plastic film is prepared from the following raw materials in parts by weight: 50-60 parts of polyurethane resin, 19-25 parts of poly (butylene succinate), 2-3 parts of flame-retardant active matter, 4-6 parts of filler, 1.5-2 parts of silane coupling agent, 0.8-1 part of antioxidant and 1-2 parts of lubricant;

the antioxidant is an antioxidant 1010, an antioxidant 300 or an antioxidant 1076;

the filler is a compound of Si C whiskers, the trachelol nanotubes, wollastonite powder and glass fibers, and the mass ratio of the SiC whiskers to the trachelol nanotubes to the wollastonite powder to the glass fibers is 10:4-5:3-4: 5-6; the pyrochlore nanotubes and wollastonite powder of the filler contain S i-O bonds and Al-O bonds, when the filler and the flame-retardant active substance are compounded for use, the silicon-phosphorus synergistic effect can further promote the carbon formation of a polymer matrix, the filler and the flame-retardant active substance react to generate silicoaluminophosphate in the combustion process, and the silicoaluminophosphate can promote the formation of phosphoric acid and enhance the oxidation, dehydration, crosslinking and carbonization processes, so that the surface of residual carbon is more compact, and a more compact carbon layer not only can play a role in heat insulation, but also can reduce the generation amount of combustible gas; the SiC whiskers and the glass fibers contained in the filler can be filled in the pores of the film to improve the mechanical property of the film, and in addition, the uniform dispersion of the filler in the plastic film can be promoted under the action of a silane coupling agent, so that the reinforcing and synergistic flame-retardant effects of the filler are exerted;

the lubricant is polyethylene wax or silicone oil;

the flame retardant active is prepared by the following method:

a1, dissolving polybutadiene in toluene, heating to 88-90 ℃ under stirring, stirring at constant temperature for 15-20min, cooling, adding acetic acid when the temperature is reduced to 38-40 ℃, adding aqueous hydrogen peroxide after the temperature is reduced to room temperature, and stirring at 200r/min for reaction for 8-9h at room temperature to obtain a mixed solution;

a2, pouring the mixed solution obtained in the step A1 into a separating funnel, adding distilled water for separating, continuously separating for 4-5 times, adding absolute ethyl alcohol into the reaction solution to separate out a product, and fully drying the separated product to obtain an intermediate;

a3, adding the intermediate into xylene, heating and stirring to dissolve the intermediate, adding hydroxymethylphenylphosphinic acid, heating to 120 ℃ under stirring, continuously stirring and reacting for 9-10h at the constant temperature of 120 ℃ under 116 ℃ and rotationally steaming, and drying the product in a vacuum drying box at 70 ℃ to constant weight to obtain a flame-retardant active substance;

the mass fraction of the aqueous hydrogen peroxide solution in the step A1 is 40%; the dosage ratio of polybutadiene, toluene, acetic acid and aqueous hydrogen peroxide solution is 1g:8-10mL:4-5mL:6-8 mL;

the dosage ratio of the intermediate, the dimethylbenzene and the hydroxymethylphenylphosphinic acid in the step A3 is 1g to 35-45mL to 0.5-0.7 g;

carbon-carbon double bonds on a polybutadiene molecular chain generate epoxy groups under the oxidation of hydrogen peroxide, and the epoxy groups and hydroxymethyl phenylphosphinic acid molecules are subjected to a ring-opening reaction with-OH connected with C, so that the hydroxymethyl phenylphosphinic acid molecules are grafted on side chains of the polybutadiene molecules to form a high-molecular flame-retardant active substance; the polymer type flame-retardant active substance has good compatibility with the polymer matrix, so that the polymer type flame-retardant active substance is uniformly distributed in the polymer matrix, and the flame-retardant effect is better exerted;

the plastic film is prepared by the following steps:

firstly, putting polyurethane resin and poly butylene succinate into a vacuum drying oven at 50-60 ℃ for drying for 12-14h to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer together, and stirring and mixing 22-25min at 8000r/min to prepare a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 165-175 ℃, and the plastic particles are subjected to extrusion and film blowing by a single-screw extruder to obtain the plastic film.

Example 1

The flame-retardant plastic film is prepared from the following raw materials in parts by weight: 50 parts of polyurethane resin, 19 parts of polybutylene succinate, 2 parts of flame-retardant active matter, 4 parts of filler, 1.5 parts of silane coupling agent, 0.8 part of antioxidant and 1 part of lubricant;

the plastic film is prepared by the following steps:

firstly, putting polyurethane resin and poly (butylene succinate) into a vacuum drying oven at 50 ℃ for drying for 14h to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer together, and stirring and mixing 22 min at 8000r/min to prepare a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 165 ℃, and performing extrusion and film blowing on the plastic particles through the single-screw extruder to obtain the plastic film.

Example 2

The flame-retardant plastic film is prepared from the following raw materials in parts by weight: 55 parts of polyurethane resin, 22 parts of polybutylene succinate, 2.5 parts of flame-retardant active matter, 5 parts of filler, 1.8 parts of silane coupling agent, 0.9 part of antioxidant and 1.5 parts of lubricant;

the plastic film is prepared by the following steps:

firstly, putting polyurethane resin and poly (butylene succinate) into a vacuum drying oven at 55 ℃ for drying for 13h to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer together, and stirring and mixing 23 min at 8000r/min to prepare a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 170 ℃, and extruding and film blowing are performed on the plastic particles through the single-screw extruder to obtain the plastic film.

Example 3

The flame-retardant plastic film is prepared from the following raw materials in parts by weight: 60 parts of polyurethane resin, 25 parts of polybutylene succinate, 3 parts of flame-retardant active matter, 6 parts of filler, 2 parts of silane coupling agent, 1 part of antioxidant and 2 parts of lubricant;

the plastic film is prepared by the following steps:

firstly, putting polyurethane resin and poly (butylene succinate) into a vacuum drying oven at 60 ℃ for drying for 12 hours to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer together, and stirring and mixing the mixture at 8000r/min for 25min to obtain a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 175 ℃, and performing extrusion and film blowing on the plastic particles through a single-screw extruder to obtain the plastic film.

Comparative example 1

The flame-retardant active substance from example 1 was replaced by hydroxymethylphenylphosphinic acid, and the remaining starting materials and preparation were unchanged.

Comparative example 2

The filler material in example 1 was removed and the remaining materials and preparation were unchanged.

Cutting the plastic films prepared in the examples 1-3 and the comparative examples 1-2 into standard test sizes, and testing the mechanical properties of the films according to ASTM D882-2010, including tensile strength, elongation at break and tear strength; the plastic films prepared in examples 1 to 3 and comparative examples 1 to 2 were cut into a standard test size, and the limiting oxygen index LOI and the vertical burning rating of each film were tested; the test results are shown in the following table:

as can be seen from the above table, the plastic films prepared in examples 1-3 have tensile strength of 55.6-56.4MPa, elongation at break of 10.4-10.9, and tear strength of 94.2-95.3, which indicates that the plastic films prepared by the invention have good mechanical properties; the LOI index of the plastic films prepared in the examples 1 to 3 is 28.6 to 28.9 percent, which shows that the plastic films prepared by the invention have good flame retardant property; compared with the comparative example 1, the mechanical property of the plastic film can be improved by adding the filler; compared with the comparative example 2, the flame retardant can be obviously improved by adding the flame retardant, and the filler and the flame retardant have a synergistic flame retardant effect.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims (8)

1. The flame-retardant plastic film is characterized by being prepared from the following raw materials in parts by weight: 50-60 parts of polyurethane resin, 19-25 parts of poly (butylene succinate), 2-3 parts of flame-retardant active matter, 4-6 parts of filler, 1.5-2 parts of silane coupling agent, 0.8-1 part of antioxidant and 1-2 parts of lubricant;

the plastic film is prepared by the following steps:

firstly, putting polyurethane resin and poly butylene succinate into a vacuum drying oven at 50-60 ℃ for drying for 12-14h to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer, and stirring and mixing for 22-25min at 8000r/min to obtain a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 165-175 ℃, and the plastic particles are subjected to extrusion and film blowing by a single-screw extruder to obtain the plastic film.

2. The flame retardant plastic film according to claim 1, wherein the antioxidant is antioxidant 1010, antioxidant 300 or antioxidant 1076.

3. The flame-retardant plastic film according to claim 1, wherein the filler is a composite of SiC whiskers, the trachelospermine nanotubes, wollastonite powder and glass fibers, and the mass ratio of the SiC whiskers, the trachelospermine nanotubes, the wollastonite powder and the glass fibers is 10:4-5:3-4: 5-6.

4. The flame retardant plastic film according to claim 1, wherein the lubricant is polyethylene wax or silicone oil.

5. The flame retardant plastic film according to claim 4, wherein the flame retardant active is prepared by the process comprising:

a1, dissolving polybutadiene in toluene, heating to 88-90 ℃ under stirring, stirring at constant temperature for 15-20min, cooling, adding acetic acid when the temperature is reduced to 38-40 ℃, adding aqueous hydrogen peroxide after the temperature is reduced to room temperature, and stirring and reacting at 200r/min for 8-9h at room temperature to obtain a mixed solution;

a2, pouring the mixed solution obtained in the step A1 into a separating funnel, adding distilled water for separating, continuously separating for 4-5 times, adding absolute ethyl alcohol into the reaction solution to separate out a product, and fully drying the separated product to obtain an intermediate;

a3, adding the intermediate into xylene, heating and stirring to dissolve the intermediate, adding hydroxymethyl phenylphosphinic acid, heating to 120 ℃ under stirring, continuously stirring and reacting for 9-10h at the constant temperature of 120 ℃ under 116 ℃ and rotationally steaming, and drying the product in a vacuum drying box at 70 ℃ to constant weight to obtain the flame-retardant active substance.

6. The flame-retardant plastic film according to claim 5, wherein the mass fraction of the aqueous hydrogen peroxide solution in the step A1 is 40%; the dosage ratio of the polybutadiene, the toluene, the acetic acid and the aqueous hydrogen peroxide solution is 1g:8-10mL:4-5mL:6-8 mL.

7. The flame retardant plastic film according to claim 5, wherein the amount of intermediate, xylene and hydroxymethylphenylphosphinic acid used in step A3 is in a ratio of 1g to 35-45mL to 0.5-0.7 g.

8. The method for preparing a flame-retardant plastic film according to claim 1, which comprises the following steps:

firstly, putting polyurethane resin and poly butylene succinate into a vacuum drying oven at 50-60 ℃ for drying for 12-14h to obtain a pretreated substrate;

secondly, putting the pretreated substrate, the flame-retardant active substance, the filler, the silane coupling agent, the lubricant and the antioxidant into a high-speed mixer, and stirring and mixing for 22-25min at 8000r/min to obtain a mixed material;

and thirdly, adding the blend into a charging barrel of a double-screw extruder, and then performing melt extrusion, water cooling, grain cutting and drying to obtain plastic particles, wherein the extrusion temperature is 165-175 ℃, and the plastic particles are subjected to extrusion and film blowing by a single-screw extruder to obtain the plastic film.