JP5235186B2 - Flame retardant resin film for curing nuclear power generation - Google Patents

Description

  The present invention relates to a flame-retardant resin film for curing nuclear power generation that has a high degree of flame retardancy.

  In facilities that handle radioactive substances such as nuclear power plants, in order to prevent accidents during inspection and repair work, equipment, floors, walls, etc. are covered with a curing film, or specific areas are partitioned with sheets. Therefore, resin films and resin sheets are used.

  These films and sheets have various flame retardants to prevent fire, transparency to ensure work efficiency and safety, flexibility to meet the workability of the coating, etc. Therefore, necessary studies have been made to meet such demands.

For example, in Patent Document 1 below, 0.2 parts by mass to 1.6 parts by mass of a NOR type light stabilizer is blended with 100 parts by mass of a polypropylene homopolymer resin having a melt flow rate of 3 to 20, which is difficult. The limiting oxygen index, which is a flammability index, is 28 or more, and the thickness is 30 μm to 100
A curing sheet for nuclear power plants that is μm is described.

  Moreover, in the following patent document 2, in a curing film for a nuclear facility consisting of three layers, the middle layer is a layer made of a composition containing 100 parts by weight of a thermoplastic polyurethane resin and 10 to 50 parts by weight of melamine cyanurate. In addition, a curing film for a nuclear facility is described in which the outer layers formed on both surfaces of the middle layer are layers made of a composition containing 100 parts by weight of a polyester resin and 0 to 50 parts by weight of melamine cyanurate. Yes.

JP 2004-238482 A JP 2005-349612 A

  However, in the prior art, a film satisfying the high flame retardancy and transparency required as a resin film used for curing nuclear power generation has not been obtained.

  That is, the objective of this invention is providing the flame-retardant resin film for nuclear power generation curing which has the outstanding flame retardance and transparency.

The gist of the present invention includes (1) 0.5 to 3.0 parts by weight of a NOR-type hindered amine derivative with respect to 100 parts by weight in total of 5 to 95 parts by weight of a random polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer. Random polypropylene resin 100 on both sides of the base layer
A laminated film having a structure in which an outer layer containing 0.5 to 3.0 parts by weight of a NOR-type hindered amine derivative is laminated with respect to parts by weight, the melt flow rate (JIS) of the resin composition constituting the laminated film K7210, 230 ° C., 2.16 kgf) is 40 g / 10
Min. And a haze value of 5% or less, a flame retardant resin film for curing nuclear power generation,
(2) The above-mentioned thermoplastic elastomer is a thermoplastic elastomer obtained by multistage polymerization in which a hard segment part is an ethylene / propylene copolymer block polymerized by using a metallocene catalyst. Flame retardant resin film,
(3) The nuclear power generation curing as described in (1) or (2) above, wherein the melt flow rate (JIS K7210, 230 ° C., 2.16 kgf) of the resin composition constituting the flame retardant resin film is 50 g / 10 min or more. Flame retardant resin film (4) The present invention resides in the flame retardant resin film for curing nuclear power generation according to any one of the above (1) to (3), which has an oxygen index of 26.0 or more.

  According to the present invention, the flame retardancy for nuclear power generation curing has high flame retardancy and transparency required as a film used in a facility handling radioactive materials such as a nuclear power plant, and has excellent mechanical strength and flexibility. A functional resin film can be provided.

  The random polypropylene resin used in the present invention is not particularly limited as long as it is a copolymer obtained by randomly copolymerizing propylene and a monomer other than propylene, such as a copolymer using ethylene or 1-butene. Used. According to this, compared with the polypropylene resin and block polypropylene resin which consist only of a propylene unit, the resin film excellent in transparency and a softness | flexibility can be obtained.

  The NOR-type hindered amine derivative used in the present invention is not particularly limited, and any hindered amine derivative in which H of the imino group (> N—H) of the piperidine ring is substituted with an alkoxyl group (—OR) can be used. Is also used.

  The thermoplastic elastomer used in the present invention is preferably a polyolefin-based thermoplastic elastomer, for example, a diene rubber (elastomer) such as isoprene rubber, butadiene rubber, butyl rubber, propylene-butadiene rubber, acrylonitrile-butadiene rubber and acrylonitrile-isoprene rubber. , Ethylene-propylene copolymer rubber, ethylene-propylene non-conjugated diene rubber, ethylene-butadiene copolymer rubber, low crystalline propylene homopolymer having a crystal melting heat (ΔH) of 100 g / J or less, obtained by a multistage polymerization method And polyolefin obtained by dynamically crosslinking a mixture of the above rubber (component) with a polyethylene resin and / or a polypropylene resin.

  The crystal melting heat (ΔH) is a value calculated from the melting peak area when dissolved at a rate of 10 ° C./min using a differential scanning calorimeter (DSC). The polyolefin obtained by a legal method is a copolymer obtained by multistage polymerization of (i) hard segment and (ii) soft segment in two or more stages in a reactor. (I) As a hard segment, a propylene homopolymer block or a copolymer block of propylene and an α-olefin, for example, binary such as propylene / ethylene, propylene / 1-butene, propylene / ethylene / 1-butene Or a terpolymer block is mentioned. In addition, (ii) as a soft segment, an ethylene homopolymer block or a copolymer block of ethylene and α-olefin, such as ethylene / propylene, ethylene / 1-butene, ethylene / propylene / 1-butene, etc. Examples include binary or ternary copolymer blocks.

  In a preferred embodiment of the present invention, since the polyolefin-based thermoplastic elastomer is particularly excellent in transparency, (i) an ethylene / propylene copolymer block in which the hard segment portion is polymerized using a metallocene catalyst is preferable. . According to this, since it is excellent in transparency, it becomes easy to distinguish the other from the inside and outside of the flame retardant resin film for curing nuclear power generation, so that the efficiency and safety in operation when using this film can be improved. Can be secured.

  In the present invention, the total content of the three components of the above-mentioned random polypropylene resin, thermoplastic elastomer, and NOR-type hindered amine derivative, which are the main components of the flame retardant resin film for curing nuclear power generation, is flame retardant for nuclear power curing. It is preferable that it is 80 to 100 weight% of the whole resin film.

  In addition to the above-described components, each layer constituting the flame-retardant resin film for curing nuclear power generation according to the present invention can contain other synthetic resins and various additives as necessary, for example, a heat stabilizer. Antioxidants, ultraviolet absorbers, lubricants, antiblocking agents, colorants and the like can be used, but the content of components other than the above three main components is 20% of the total flame retardant resin film for curing nuclear power generation. It is preferable that it is below wt%.

  Other synthetic resins to be mixed are not particularly limited. For example, styrene-butadiene-based thermoplastic elastomers such as styrene-butadiene copolymer rubber (SBR) and styrene-butadiene block copolymer, and styrene-isoprene copolymer rubber. And styrene-based thermoplastic elastomers (including these hydrogenated products).

  The flame-retardant resin film for curing nuclear power generation of the present invention is a laminated film having a three-layer structure in which outer layers are laminated on both front and back surfaces of a base layer, and the melt flow rate of the resin composition constituting the laminated film ( JIS K7210, 230 ° C., 2.16 kgf) is 40 g / 10 min or more and a haze value of 5% or less.

  The base layer is a layer containing 0.5 to 3.0 parts by weight of a NOR type hindered amine derivative with respect to 100 parts by weight in total of 5 to 95 parts by weight of a random polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer. is there. The outer layer is a layer containing 0.5 to 3.0 parts by weight of a NOR type hindered amine derivative with respect to 100 parts by weight of a random polypropylene resin.

  Thus, since the flame retardant resin film for curing nuclear power generation according to the present invention does not contain a polyvinyl chloride resin or a flame retardant such as a halogen compound, generation of harmful gas at the time of disposal can be suppressed. In addition, by coating the base layer containing the thermoplastic elastomer with an outer layer that does not contain the thermoplastic elastomer, the surface of the flame-retardant resin film for curing nuclear power generation has a unique sticky feeling due to the thermoplastic elastomer. Can be prevented.

In the preferable aspect of this invention, content of the said thermoplastic elastomer in a base layer is 5-95 weight part, More preferably, it is 40-80 weight part. If the amount of the thermoplastic elastomer is greater than the above specified value, the processability of the film is lowered, and if the amount of the thermoplastic elastomer is less than the above specified value, the film lacks flexibility.

In a preferred embodiment of the present invention, the content of the NOR type hindered amine derivative in each layer is preferably 0.5 to 2 parts by weight, more preferably 0.5 to 1.5 parts by weight. If the amount of the NOR type hindered amine derivative is larger than the specific value, the processability of the film is lowered. If the amount of the NOR type hindered amine derivative is less than the specific value, the flame retardancy is insufficient.

  In a preferred embodiment of the present invention, the melt flow rate (JIS K7210, 230 ° C., 2.16 kgf) of the resin composition constituting the flame retardant resin film for curing nuclear power generation is 40 g / 10 min or more, more preferably It is 50 g / 10 minutes or more. When the melt flow rate value is lower than the above specific value, flame retardancy cannot be obtained. On the other hand, if the melt flow rate value is higher than 200 g / 10 min, the molecular weight is too small, so that the film strength becomes insufficient, which is not preferable.

  In a preferred embodiment of the present invention, the oxygen index of the flame retardant resin film for curing nuclear power generation is 26.0 or more. When the oxygen index is higher than the above specific value, the flame retardancy of the film becomes insufficient, which is not preferable.

  In the preferable aspect of this invention, the haze value of the resin composition which comprises this flame-retardant resin film for nuclear power generation curing is 5% or less. When the haze value is higher than the above specific value, the transparency of the flame-retardant resin film for curing nuclear power generation is not preferable.

  In the preferable aspect of this invention, the thickness of this flame retardant resin film for nuclear power generation curing is 0.03-0.2 mm, More preferably, it is 0.06-0.15 mm. If the thickness of the flame retardant resin film for curing nuclear power generation is thinner than the above specified value, the film is easily broken, and if the thickness of the flame retardant resin film for curing nuclear power generation is thicker than the above specified value, The flexibility of the film is impaired. In the flame-retardant resin film for curing nuclear power generation according to the present invention, the preferred ratio of the thickness of each layer is the outer layer (the total thickness of the two layers): the base layer is 1: 9-7: 3, more preferably. 2: 8-6: 4.

  In a preferred embodiment of the present invention, the three-layer structure comprising the above-described base layer and outer layers located on both sides thereof is 80 to 100% by weight of the whole flame-retardant resin film for curing nuclear power generation.

The flame-retardant resin film for curing nuclear power generation according to the present invention can contain other additives and adhesives of the above three-layer structure, other synthetic resin layers, etc., if necessary. The layers other than the three-layer structure are preferably 20% by weight or less of the whole flame-retardant resin film for curing nuclear power generation.

  Next, the manufacturing method of the flame retardant resin film for nuclear power generation curing of this invention is demonstrated.

The flame-retardant resin film for curing nuclear power generation according to the present invention has a NOR type hindered amine derivative of 0.5 to 3.0 with respect to a total of 100 parts by weight of 5 to 95 parts by weight of a random polypropylene resin and 5 to 95 parts by weight of a plastic elastomer. A laminated film having a base layer each containing parts by weight and an outer layer containing 0.5 to 3.0 parts by weight of a NOR-type hindered amine derivative with respect to 100 parts by weight of a random polypropylene resin on both the front and back surfaces of the base layer, It can be produced by an extrusion method.

  The melt flow rate of the resin composition at the time of extrusion is 1 to 20 g / 10 minutes, preferably 5 to 15 g / 10 minutes. When the melt flow rate of the resin composition is lower than the above specific value, there is a problem that the melt viscosity becomes too high and it is difficult to extrude, and the melt flow rate value is higher than the above specific value. In this case, the melt viscosity becomes too low and the fluidity becomes high, which makes it difficult to process. Moreover, the flame-retardant resin film for curing nuclear power generation according to the present invention can be stretched as necessary.

  In the present invention, as means for obtaining a laminated film composed of a resin composition having a melt flow rate of 40 g / 10 min or more, for example, the laminated film is irradiated with radiation. In this case, the irradiation method is not particularly limited, and a known irradiation device can be used. For example, a cockroft Walton type, a bandegraph type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, a high frequency An electron beam irradiation apparatus such as a mold can be used.

  The flame retardant resin film for curing nuclear power generation obtained in this way is excellent in mechanical strength and flexibility and has no sticky feeling on the film surface. In addition, the MFR is 40 g / 10 min or more, which is combined with high flame retardancy, and the haze value is 5% or less and excellent in transparency. It is suitable as a film used in a facility that handles the film, and even a film for other uses can be used as a film for uses requiring high flame retardancy and transparency.

  Embodiments of the present invention will be described in detail below with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

<Examples 1-2>
According to the formulation described in Table 1, dry blended in a pellet state, and the blended raw materials are put into a hopper of a single screw extruder (50φ mm, L / D = 32) manufactured by Toshiba Machine, and the extruder temperature is set to C1: The temperature was set to 210 ° C, C2: 240 ° C, C3: 240 ° C, C4: 240 ° C, C5: 240 ° C, and extruded from a 550 mm wide T die (temperature setting 240 ° C, lip opening 0.3 mm). The extruded molten resin is cooled and solidified by a winder (cooling roll 700 mm width × φ350 mm, roll temperature 30 ° C.) equipped with a cooling roll, and accelerated voltage using ELECTRO CURTAIN CB170 (I-Graphics). Electron beam irradiation was performed at 165 kV to obtain laminated films of Examples 1 and 2 having different irradiation doses.

<Comparative Examples 1-4>
Each of the blends shown in Table 1 was dry blended and extruded in the same manner as in Example 1. The extruded molten resin was a winder equipped with a cooling roll (cooling roll 700 mm width × φ350 mm, roll Cooling solidification and winding were performed at a temperature of 30 ° C. Then, about Comparative Examples 2-4, electron beam irradiation was performed using ELECTRO CURTAIN CB170 (eye graphics company) on the conditions similar to Example 1. FIG.

  Evaluation items were evaluated in the following manner for each obtained film.

<Evaluation>
(1) Melt flow rate The melt flow rate of the resin composition constituting the film was measured according to JIS K7210 (230 ° C., 2.16 kg load).

(2) Formability Filmability during film formation and film appearance were confirmed. Good ones were marked with ◯, badly inferior ones, and those that could not be formed into films. X cannot be put to practical use.

(3) A test piece (dimensions: length 130 mm, width 65 mm) is taken from the flame retardant evaluation film, and the test piece is burned in accordance with a combustion test method for a polymer material by the oxygen index method of JIS K 7201. Measure the flow rate of oxygen and the flow rate of nitrogen required for the test piece to burn continuously for 3 minutes or more, or to continue burning after the flame has burned for 50 mm or longer. The oxygen index was obtained from the formula (A), and the flame retardancy was evaluated based on the oxygen index. In addition, a flame retardance is so high that the value of an oxygen index is large.
Oxygen index (O.I.) = {[O2] / ([O2] + [N2])} × 100 (A)
(In the formula, [O2] is the flow rate of oxygen (l / min), and [N2] is the flow rate of nitrogen (l / min).)

(4) Evaluation of transparency According to JIS K 7105, the haze of the test piece collected from the film was measured.

In the examples and comparative examples, the respective resins and compounding agents are specifically as follows.
PP: Random PP (Nippon Polypro Co., Ltd., Novatec PP FX3A MFR 8.5 g / 10 min)
Elastomer (A); Olefin-based elastomer (manufactured by Nippon Polypro Co., Ltd., Wellnex RFG4VA MFR6g / 10min)
Elastomer (B); Olefin-based elastomer (manufactured by Sun Allomer Co., Ltd., Catalloy C200F MFR 6 g / 10 min)
NOR: NOR type hindered amine derivative (FLAMESTAB NOR116FF manufactured by Ciba Japan)
In the elastomer (A), the hard segment portion is polymerized using a metallocene catalyst, and in the elastomer (B), the hard segment portion is obtained using a Ziegler-Natta catalyst or the like.

  The composition according to the present invention can produce a film having a good appearance by extrusion, and the obtained film of the present invention is excellent in flame retardancy and transparency. (Examples 1-2). In particular, Example 2 in which the melt flow rate (JIS K7210, 230 ° C., 2.16 kgf) of the resin composition is 55 g / 10 min is more excellent in flame retardancy and is preferable as a flame retardant resin film for curing nuclear power generation. It turns out that. On the other hand, although the film of Comparative Examples 1-2 was excellent in transparency, it was inferior to a flame retardance. Moreover, although the film of Comparative Example 3 was excellent in flame retardancy, it was inferior in transparency. That is, the films of Comparative Examples 1 to 3 were not preferable as a flame retardant resin film for curing nuclear power generation. Moreover, since the comparative example 4 had too much content of a NOR type hindered amine derivative, it turned out that workability is bad and it is difficult to manufacture a film.

Claims (4)

Random polypropylene is used on both sides of the base layer containing 0.5 to 3.0 parts by weight of a NOR-type hindered amine derivative with respect to 100 parts by weight in total of 5 to 95 parts by weight of a random polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer. A laminated film having a structure in which an outer layer containing 0.5 to 3.0 parts by weight of a NOR-type hindered amine derivative is laminated on 100 parts by weight of a resin, and the melt flow of the resin composition constituting the laminated film A flame retardant resin film for curing nuclear power generation, characterized by having a rate (JIS K7210, 230 ° C., 2.16 kgf) of 40 g / 10 min or more and a haze value of 5% or less. The flame retardant resin for curing nuclear power generation according to claim 1, wherein the thermoplastic elastomer is a thermoplastic elastomer obtained by multistage polymerization in which a hard segment part is an ethylene / propylene copolymer block polymerized using a metallocene catalyst. the film. The flame-retardant resin film for curing nuclear power generation according to claim 1 or 2, wherein the melt flow rate (JIS K7210, 230 ° C, 2.16 kgf) of the resin composition constituting the flame-retardant resin film is 50 g / 10 min or more. The flame retardant resin film for curing nuclear power generation according to any one of claims 1 to 3, wherein the oxygen index is 26.0 or more.