JP2013139499A - Flame retardancy synthetic resin film and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame retardancy synthetic resin film in which the molding is easy, that has a moderate flexibility, and that passes a UL-94VTM-0 standard.SOLUTION: The flame retardancy synthetic resin film includes: 40 to 80 pts.mass of pyrophosphate piperazine; and 20 to 60 pts.mass of melamine cyanurate based on 100 pts.mass of a polyolefin that contains a proper quantity of other components in addition to a major component of an ethylene-oxygen-containing monomer copolymer, wherein crystallinity is decreased by the oxygen-containing monomer, thereby even when being molded in a film form of 0.1 to 0.3 mm of a thickness, the film itself is not hardened to be flexible; and a calorific value is lowered by the oxygen-containing monomer, thereby flame retardancy is improved while mechanical properties of the film itself are kept.

Description

  The present invention relates to a flexible flame-retardant synthetic resin film excellent in flexibility and a method for producing the flame-retardant synthetic resin film.

  The flame retardant resin composition described in the following Patent Document 1 includes 10 to 70 parts by mass of piperazine pyrophosphate, 70 parts by mass of melamine cyanurate 1 with respect to 70 parts by mass of a polypropylene resin (manufactured by Prime Polymer: J-750HP injection molding grade). -30 mass parts, 0.01-1 mass part of anti-drip agent, and 0.1-4 mass parts of metal oxide are mix | blended. This flame retardant resin composition is tested with a test piece having a thickness of 1.6 mm based on UL-94 (vertical combustion test method) of UL standards as a flame retardant test. The flame retardance which passes V-0 which is evaluation is shown (for example, refer patent document 1).

JP 2011-148936 A

Such a conventional flame retardant resin composition passes the UL94 vertical burning test (V-0) standard using a 1.6 mm thick test piece, but is formed into a thin film. Good flame retardancy cannot be obtained. For example, when the UL94V-0 test is performed with a thin film-shaped test piece of about 0.1 to 0.3 mm, one of the criteria is “whether the cotton is ignited by flame particles or flame drops (droplets). "Cotton ignition by") fails.
For this reason, it has been difficult to pass the UL-94 Thin Material Vertical Burning Test (VTM-0) standard corresponding to a thin film.
By the way, when forming into a thin film of about 0.1 to 0.3 mm using homopolypropylene which is a homopolymer of polypropylene, the homopolypropylene is crystalline and has a melting point (160 to 170 ° C., equilibrium melting point is 185). (˜190 ° C.) was high and had to be processed at a high temperature.
And homopolypropylene has a problem that it becomes too hard when a large amount of flame retardant is blended.
Furthermore, when the polypropylene flame retardant resin composition is formed into a thin film having a thickness of about 0.1 to 0.3 mm by an ordinary extrusion molding, the surface of the film is not smooth and has no commercial properties. This phenomenon is presumed to be due to aggregation of piperazine pyrophosphate and decomposition of melamine cyanurate. This phenomenon is considered to occur because the processing temperature (220 to 230 ° C.) of the polypropylene film is too high. This phenomenon is considered to be unavoidable when the molding temperature is high.
In addition, the calendar molding usually performed as a film molding method tends to be insufficiently dispersed even if the flame retardant is made into a master batch. The polypropylene flame retardant resin composition has a problem that the surface of the film is not smooth and has no commercial properties in a calendar line that does not use Banbury. Even in calendar molding at a normal Banbury temperature (150 to 160 ° C.), there is a problem that the smoothness is insufficient.

  This invention makes it a subject to cope with such a problem, and provides a flame-retardant synthetic resin film which is easy to form a film, has appropriate flexibility, and passes the UL-94 VTM-0 standard. It is for the purpose.

  In order to achieve such an object, the flame-retardant synthetic resin film according to the present invention is composed of 40-80 parts by mass of piperazine pyrophosphate with respect to 100 parts by mass of a polyolefin mainly composed of an ethylene-oxygen-containing monomer copolymer, It contains 20 to 60 parts by mass of melamine cyanurate and is formed into a film having a thickness of 0.1 to 0.3 mm.

  In addition to the above-described features, the piperazine pyrophosphate 40 to 100 parts by mass of the polyolefin composed of 55 to 90 parts by mass of the ethylene-oxygen-containing monomer copolymer and 10 to 45 parts by mass of polypropylene. It contains 80 parts by mass and 20-60 parts by mass of the melamine cyanurate.

  Furthermore, in addition to the above-described characteristics, the content of the oxygen-containing monomer contained in the ethylene-oxygen-containing monomer copolymer is 10 to 25% by mass.

The flame-retardant synthetic resin film according to the present invention having the above-described characteristics is obtained by adding pyrophosphoric acid to 100 parts by mass of polyolefin containing an appropriate amount of other components in addition to the ethylene-oxygen-containing monomer copolymer as a main component. By blending 40-80 parts by mass of piperazine and 20-60 parts by mass of melamine cyanurate, the crystallinity is lowered with an oxygen-containing monomer, so it is formed into a film having a thickness of 0.1-0.3 mm. However, the film itself does not become hard and flexible, and the calorific value is reduced by the oxygen-containing monomer, so that flame retardancy is improved while maintaining the mechanical properties of the film itself, so film formation is easy and moderate It is possible to provide a flame-retardant synthetic resin film that has excellent flexibility and passes the UL-94 VTM-0 standard.
As a result, a film having a thickness of 0.1 to 0.3 mm can be formed even if the molding temperature is lower than that of the extrusion molding method, and the film itself does not need to be formed at a high temperature. Can also be prevented from browning.
Further, it can be used in, for example, electric / electronic devices that require the UL-94 standard to pass as a flame retardant standard.

Particularly, piperazine pyrophosphate 40-80 parts by mass, melamine cyanurate 20 with respect to 100 parts by mass of polyolefin comprising 55-90 parts by mass of ethylene-oxygen-containing monomer copolymer and 10-45 parts by mass of polypropylene. In the case of containing -60 parts by mass, the blending of polypropylene does not cause cotton ignition due to the drop in the UL-94 VTM-0 test, and at the same time, the film itself becomes hard and flexible. In other words, when the blending amount of polypropylene is less than 10 parts by mass, cotton ignition due to the drop is likely to occur in the UL-94VTM-0 test. On the other hand, when the blending amount of polypropylene is more than 45 parts by mass, the film itself becomes too hard to achieve the hardness intended by the present invention.
Thereby, while the moldability of a film can be improved further, UL-94VTM-0 specification can be passed more reliably.

Furthermore, in the case where the content of the oxygen-containing monomer contained in the ethylene-oxygen-containing monomer copolymer is 10 to 25% by mass, the crystallinity is increased by the inclusion of the oxygen-containing monomer. Since it decreases, it becomes flexible, and the oxygen index becomes large and has an effect of improving flame retardancy. In other words, when the content of the oxygen-containing monomer is less than 10% by mass, the film itself becomes too hard and does not have the hardness intended by the present invention. On the other hand, when the content of the oxygen-containing monomer is more than 25% by mass, the film itself becomes too soft and there is a problem in use.
Thereby, it is possible to provide a flame-retardant synthetic resin film having further appropriate flexibility and high flame retardancy.

Hereinafter, embodiments of the present invention will be described in detail.
The flame-retardant synthetic resin film according to the embodiment of the present invention is composed of 40 to 80 parts by mass of piperazine pyrophosphate and 20 to 20 parts of melamine cyanurate with respect to 100 parts by mass of a polyolefin mainly composed of an ethylene-oxygen-containing monomer copolymer. It contains 60 parts by mass and is formed by molding into a film having a thickness of 0.1 to 0.3 mm.

The polyolefin of the flame-retardant synthetic resin film according to the embodiment of the present invention uses an ethylene-oxygen-containing monomer copolymer as its main component, and as other blending components from an appropriate amount of polypropylene, polyethylene, polybutene, and the like. One or two or more selected polymers are used, but it is preferable to blend polypropylene from the viewpoint of heat resistance.
Furthermore, in order to improve flexibility and flame retardancy, the blending ratio of the two is preferably 55 to 90 parts by mass of ethylene-oxygen-containing monomer copolymer and 10 to 45 parts by mass of polypropylene.
Further, as polypropylene, it is preferable to use random polypropylene which is a random copolymer or homopolypropylene which is a homopolymer.

Examples of the ethylene-oxygen-containing monomer copolymer include an ethylene-alkyl (meth) acrylate copolymer, an ethylene-vinyl acetate copolymer (EVA), an ethylene-vinyl alcohol copolymer (EVOH), and an ethylene- (meta). ) Acrylic acid copolymer and ionomer (IO). One or two or more types of copolymers selected from here are used.
In particular, an ethylene-alkyl (meth) acrylate copolymer is preferably used, and an ethylene-vinyl acetate copolymer (EVA) can also be used.

Furthermore, in order to improve flexibility and flame retardancy, the content of the oxygen-containing monomer contained in the ethylene-oxygen-containing monomer copolymer is preferably 10 to 25% by mass.
That is, when the ethylene-oxygen-containing monomer copolymer is an ethylene-alkyl (meth) acrylate copolymer, its oxygen-containing single amount with respect to the total mass of the ethylene-alkyl (meth) acrylate copolymer It is preferable that an acrylate (acrylic acid ester) and a methacrylate (methacrylic acid ester) contain 10-25 mass% as a body.
Furthermore, when an ethylene-methyl methacrylate copolymer having a methacrylate content of 20% by mass or more is used as the ethylene-oxygen-containing monomer copolymer, the Young's modulus is preferably set to 50 to 700 MPa.
In addition, when the ethylene-oxygen-containing monomer copolymer is an ethylene-vinyl acetate copolymer (EVA), the oxygen-containing single amount with respect to the total mass of the ethylene-vinyl acetate copolymer (EVA). It is preferable that vinyl acetate (VA) contains 10-25 mass% as a body.

The ethylene-alkyl (meth) acrylate copolymer includes ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl. Examples thereof include acrylate copolymers, ethylene-butyl methacrylate copolymers, ethylene-hexyl acrylate copolymers, ethylene-hexyl methacrylate copolymers, ethylene-lauryl acrylate copolymers, ethylene-lauryl methacrylate copolymers.
Among these, it is preferable to use an ethylene-methyl methacrylate copolymer (EMMA).
In particular, when ethylene-methyl methacrylate copolymer (EMMA) is used, 10 to 10 methyl methacrylate (MMA) is used as the oxygen-containing monomer with respect to the total mass of ethylene-methyl methacrylate copolymer (EMMA). It is preferable to contain 25 mass%.

As the piperazine pyrophosphate, piperazine pyrophosphate described in, for example, JP-A-48-087991 and US Pat. No. 4,599,375 is used.
The amount of piperazine pyrophosphate added decreases the flame retardancy of the obtained flame retardant synthetic resin film, and the increase in the amount reduces the mechanical properties of the obtained flame retardant synthetic resin film. The amount is 40 to 80 parts by mass, preferably 50 to 60 parts by mass with respect to 100 parts by mass of the polyolefin mainly composed of the monomer copolymer.

Melamine cyanurate is a powdered product of the reaction product of melamine and cyanuric acid. It has a large amount of nitrogen atoms in its structure and generates nitrogen gas when exposed to high temperatures of about 350 ° C or higher. It works to inhibit combustion. Although cyanuric acid has two tautomers, an enol type and a keto type, cyanuric acid as used in the present invention means both an enol type and a keto type.
When the amount of melamine cyanurate is decreased, the flame retardancy of the obtained flame retardant synthetic resin film is lowered, and when it is increased, the mechanical properties of the obtained flame retardant synthetic resin film are lowered. It is 20-60 mass parts with respect to 100 mass parts of polyolefin mainly having a monomer copolymer, Preferably it is 30-40 mass parts.

Furthermore, in the flame-retardant synthetic resin film according to the embodiment of the present invention, it is preferable to blend a known general anti-drip agent in order to prevent resin dripping (drip) during combustion.
Specific examples of the anti-drip agent include, for example, fluorine resins such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride, polyhexafluoropropylene, sodium perfluoromethanesulfonate, and potassium perfluoro-n-butanesulfonate. Perfluoroalkanesulfonic acid alkali metal salts such as perfluoro-t-butanesulfonic acid potassium salt, perfluorooctanesulfonic acid sodium salt, perfluoro-2-ethylhexanesulfonic acid calcium salt, or perfluoroalkanesulfonic acid alkaline earth Metal salts and silicone rubbers can be mentioned, and these can be used alone or in combination of two or more. Among these, PTFE is particularly preferably used since it has an excellent drip prevention effect.
When the amount of PTFE is decreased, the drip prevention effect of the flame-retardant synthetic resin film is small, and when it is increased, the cost of the flame-retardant synthetic resin film is increased. Therefore, the ethylene-oxygen-containing monomer copolymer is mainly used. It is 0.1-10 mass parts with respect to 100 mass parts of made polyolefin, Preferably it is 1-5 mass parts.

Furthermore, in the flame-retardant synthetic resin film according to the embodiment of the present invention, it is preferable to blend a metal oxide as an essential component in order to further improve flame retardancy. Specific examples of the metal oxide include titanium oxide, zinc oxide, magnesium oxide, strontium oxide, and the like, and these can be used alone or in combination of two or more. Among these, titanium oxide is particularly suitable because it is excellent in flame retardancy and heat resistance.
When the amount of titanium oxide added decreases, the flame retardancy of the resulting flame retardant synthetic resin film decreases, and when it increases, the flame retardant of the obtained flame retardant synthetic resin film increases, but the kneaded product foams during production. Since the discharge and the resin pressure may become unstable, it is 0.1 to 2 parts by mass with respect to 100 parts by mass of the polyolefin mainly composed of an ethylene-oxygen-containing monomer copolymer, preferably Is 0.5 to 1 part by mass.

Moreover, it is preferable to mix | blend a fatty-acid metal salt (metal soap) as a lubricant at the time of shape | molding the flame-retardant synthetic resin film which concerns on embodiment of this invention into a film form, for example by calendar molding.
The addition amount of the fatty acid metal salt is 0.01 to 10 parts by mass, preferably 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the polyolefin mainly composed of the ethylene-oxygen-containing monomer copolymer. Part.
Furthermore, if necessary, it may be stabilized with magnesium hydroxide, phenolic antioxidant, phosphorus antioxidant, thioether antioxidant, ultraviolet absorber, hindered amine light stabilizer, etc., or p-tert-butylbenzoic acid. Add nucleating agents such as aluminum, aromatic phosphate metal salts, dibenzylidene sorbitols, antistatic agents, hydrotalcite, triazine ring-containing compounds, fillers, pigments, lubricants, foaming agents, etc. Is also possible.

And the manufacturing method for producing the flame-retardant synthetic resin film according to the embodiment of the present invention includes, for example, calendar molding, extrusion molding, etc. as a method of forming a film having a thickness of 0.1 to 0.3 mm. Used.
Specific examples of calendar molding include a mixing (compounding) process comprising a ribbon blender, a kneading process comprising a Banbury mixer and a mixing roll, a filtration separating process comprising a strainer, a rolling process comprising a calendar roll, and the like. It has a cooling process including a cooling roll and a winding process including a winder.
In particular, after kneading the composition with a Banbury mixer as the kneading step, it is preferable to roll the film into a film of 0.1 to 0.3 mm with a calender roll as the rolling step.
As another example, it is possible to perform extrusion molding using an extruder or molding using another existing molding machine instead of calendar molding.

Examples 1-7 and Comparative Examples 1-8
The components shown in Table 1 and Table 2 were mixed at respective ratios, and a film having a thickness of 0.1 mm was obtained by calendering. Specifically, each component was mixed with a ribbon blender, kneaded with a Banbury mixer (resin temperature at discharge 170 to 180 ° C.) and a mixing roll, and then rolled with a calender roll (set temperature 175 to 185 ° C.) through a strainer.
In Tables 1 and 2, “EMMA (MMA 25%)” is ACLIFT WK-307 manufactured by Sumitomo Chemical. “EMMA (MMA 20%)” is an ACRlift WH-206 manufactured by Sumitomo Chemical. “EVA (VA 18%)” is NUC-3765D manufactured by Dow Chemical Japan. “Random polypropylene” is Nobrene FS-3611 manufactured by Sumitomo Chemical. “Homopolypropylene” is Nobrene FHX20E1 manufactured by Sumitomo Chemical. “Piperazine pyrophosphate”, “melamine cyanurate”, “PTFE”, and “titanium oxide” use phosphorous nitrogen-based flame retardant (SCRF-5N) manufactured by Sakai Chemical Co., Ltd. MC-4000 made from was used.
A plurality of test pieces having a length of 200 mm and a width of 50 mm were prepared from the obtained film having a thickness of 0.1 mm, and a UL-94 Thin Material Vertical Burning Test (VTM) -0 test was performed. It was.
Furthermore, the calendering processability was evaluated, and the hardness of each film was evaluated based on Example 1. For Examples 1, 3 to 6 and Comparative Example 8, Young's modulus (MPa) was calculated in order to quantify the hardness of each film.
The results are also shown in Tables 1 and 2. In Tables 1 and 2, blanks in the evaluation items are not measured.

The test method of UL-94VTM-0 and its judgment criteria are as follows.
Each film test piece is wound around a mandrel having a diameter of 13 mm and attached vertically to a clamp, and a 3-second indirect flame with a 20 mm flame is performed twice, and pass / fail is determined by its combustion behavior.
Judgment criteria are that the burning time of each film specimen is 10 seconds or less, that the total burning time of 5 films is 50 seconds or less, the burning + glowing time of each film specimen is 30 seconds or less, It is necessary to satisfy all that there is no combustion up to the clamp and that there is no ignition of the lower cotton (cotton ignition by dripping) due to the fire type falling from each film specimen.

As can be seen from Table 1 and Table 2, Examples 1 to 7 in which the proportion of polyolefin and the blending amount of the flame retardant are within the scope of the present invention passed the UL-94 VTM-0 standard.
As for the hardness of each film in Examples 1-6, each Young's modulus is settled in 50-700 MPa. In particular, Examples 1, 3, 4, and 6 had Young's modulus falling within 100 to 400 MPa, and had moderate flexibility in evaluating the hardness of each film.

  Furthermore, regarding the workability of calendar molding, Examples 1 to 5 could be processed without any problem. In Example 6, plate out (a phenomenon in which a part of the compounding component adheres to the processing machine surface during processing) slightly occurs, and drawdown (a phenomenon in which the film hangs down due to the film's own weight during processing) is apparent. The releasability from the roll was slightly poor, and there were some problems with the bank (how to turn the raw resin). In addition, Example 7 had problems with the same level of drawdown, release from rolls, and bank rotation as Example 6, and plateout occurred, and continuous production was limited to 30 minutes.

On the other hand, in Comparative Examples 1 and 6, since the blending amount of the flame retardants of piperazine pyrophosphate and melamine cyanurate is insufficient, the burning time of each film test piece is longer than 10 seconds, and due to the droppings. There was cotton ignition and it failed the UL-94VTM-0 standard.
In Comparative Examples 2, 3, and 7, since the blending amount of melamine cyanurate is large, it is difficult to cause cotton ignition due to dripping, but the burning time of each film specimen becomes longer than 10 seconds, and UL-94VTM- It failed to 0 standard.
In Comparative Examples 4 and 5, since the blending amount of melamine cyanurate was insufficient, there was cotton ignition due to the droppings and the UL-94VTM-0 standard was rejected.
In Comparative Example 8, polypropylene was not blended at all, and the ethylene-methyl methacrylate copolymer (EMMA) was used alone. Therefore, cotton ignition was caused by the drop and the UL-94 VTM-0 standard was rejected.

  Further, regarding calendering processability, Comparative Examples 1 to 7 could be processed without any problem. In Comparative Example 8, plate-out occurred, the film was drawn down, the release property from the roll was poor, and the bank periphery was also bad.

  And like Examples 1-5 of such this invention, an ethylene-oxygen containing monomer copolymer is an ethylene-methylmethacrylate copolymer (EMMA) whose methacrylate is 20 mass% or more, and has a Young's modulus. When the pressure was set to 50 to 700 MPa, a film having a thickness of 0.1 mm excellent in flexibility could be reliably formed without causing any trouble even by the calendar forming method.

Further, as in Examples 1 to 5, when rolled into a film having a thickness of 0.1 mm by calendering, the piperazine pyrophosphate agglomerates disappeared and particles were not formed.
Thereby, it is possible to prevent abnormal appearance and decrease in strength due to aggregation of piperazine pyrophosphate.

Furthermore, when a fatty acid metal salt (metal soap) is contained as a calendering lubricant, the melamine cyanurate has an effect of improving slipping, and therefore, calendering can be performed only with the fatty acid metal salt.
Thereby, film formation can be performed with a small amount of lubricant.

Moreover, as a manufacturing method of the flame-retardant synthetic resin film according to the present invention, when the blended components were kneaded with a Banbury mixer and then rolled with a calendar roll, the dispersibility of the blended components was increased.
Thereby, the abnormality of the external appearance and the fall of intensity | strength by aggregation of a mixing | blending component can be prevented reliably.

Claims (7)

  It contains 40-80 parts by mass of piperazine pyrophosphate and 20-60 parts by mass of melamine cyanurate with respect to 100 parts by mass of polyolefin mainly composed of an ethylene-oxygen-containing monomer copolymer, and has a thickness of 0.1-0. A flame-retardant synthetic resin film formed into a 3 mm film.   The ethylene-oxygen-containing monomer copolymer is 55 to 90 parts by mass, and polypropylene is 10 to 45 parts by mass with respect to 100 parts by mass of the polyolefin. The piperazine pyrophosphate 40 to 80 parts by mass, the melamine shear The flame-retardant synthetic resin film according to claim 1, comprising 20 to 60 parts by mass of nurate.   The flame-retardant synthetic resin according to claim 1 or 2, wherein the content of the oxygen-containing monomer contained in the ethylene-oxygen-containing monomer copolymer is 10 to 25% by mass. the film.   4. The ethylene-oxygen-containing monomer copolymer is an ethylene-methyl methacrylate copolymer of 20% by mass or more of methacrylate, and the Young's modulus is set to 50 to 700 MPa. Flame retardant synthetic resin film.   The flame-retardant synthetic resin film according to claim 1, wherein the molding is calendar molding.   6. The flame retardant synthetic resin film according to claim 5, wherein the calender molding lubricant contains a fatty acid metal salt.   When producing the flame-retardant synthetic resin film according to claim 5 or 6, the calender molding includes a kneading step using a Banbury mixer and a rolling step using a calender roll. Method.