JP5334793B2 - Flame-retardant resin film and method for producing flame-retardant resin film - Google Patents

Description

  The present invention relates to a resin film having a high degree of flame retardancy and a method for producing the flame retardant resin film.

  Conventionally, synthetic resins are flammable, so in fields that require flame retardancy and strength, such as electrical and electronic products, automobiles, and building components, they are relatively low in combustibility and have excellent mechanical properties. Vinyl chloride resins are used, and flame retardants such as halogen compounds have been used as additives.

  However, with the recent increase in environmental awareness, the use of a polyolefin resin such as a polyvinyl chloride resin or a halogen-free polyethylene resin or a polypropylene resin as a flame retardant film base material has been studied.

  For example, in the following Patent Document 1, a NOR type light stabilizer, melamine cyanurate, and phosphoric acid are formed on at least one surface of a flame retardant fabric formed from a flame retardant component-containing fiber with respect to 100 parts by mass of an olefin resin. There is described a flame retardant laminate obtained by laminating a flame retardant film formed from a resin mixture obtained by mixing 6 to 65 parts by mass of a flame retardant which is an ester compound.

  Patent Document 2 listed below includes a polyolefin film layer containing 0.5 wt% or more of a phosphate ester flame retardant and 0.4 wt% or more of a NOR type hindered amine stabilizer, and a polyolefin fiber base fabric layer. A flame retardant polyolefin composite sheet characterized by comprising:

JP 2004-174869 A JP 2002-337284 A

  However, even if the techniques described in Patent Documents 1 and 2 are used, sufficient flame retardancy is required to be used in fields requiring high flame retardancy such as electric / electronic products, automobiles, and building members. The applied resin film could not be produced.

  That is, an object of the present invention is to provide a flame retardant resin film having high flame retardancy.

  The gist of the present invention is as follows.

(1) A total of 100 parts by weight of 5 to 95 parts by weight of a polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer contains 0.5 to 3.0 parts by weight of a NOR-type hindered amine derivative , JIS K7210, 230 ° C., 2.16 kgf) 1 to 20 g / 10 min of resin composition is extruded to produce a film, and then the film is irradiated with radiation to melt the resin composition constituting the film A method for producing a flame-retardant resin film, wherein a flow rate (JIS K7210, 230 ° C., 2.16 kgf) is 40 g / 10 min or more, and a tensile breaking elongation of the film is 100% or more.

(2) The flame-retardant resin film as described in (1) above, wherein the melt flow rate (JIS K7210, 230 ° C., 2.16 kgf) of the resin composition constituting the film is 50 g / 10 min or more. Manufacturing method.
(3) The method for producing a flame-retardant resin film according to the above (1) or (2), wherein the oxygen index of the film is 26.0 or more .
(4) The method for producing a flame-retardant resin film according to any one of (1) to (3) , wherein the radiation is an electron beam.

(5) The method for producing a flame-retardant resin film according to (4) , wherein the radiation is an electron beam .

  According to the flame retardant resin film of the present invention, it is possible to provide a flame retardant resin film having high flame retardancy and excellent mechanical strength and flexibility.

  Moreover, according to the manufacturing method of the flame-retardant resin film of this invention, the method of manufacturing this flame-retardant resin film which has high flame retardance effectively and efficiently can be provided.

  The polypropylene resin used in the present invention is not particularly limited. For example, a homopolymer of propylene (homopolypropylene), a random copolymer of propylene and ethylene or another α-olefin (random polypropylene), or a block A copolymer (block polypropylene), a block copolymer containing a rubber component, a graft copolymer, or the like can be used.

  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 not particularly limited, but is preferably a polyolefin-based thermoplastic elastomer, such as isoprene rubber, butadiene rubber, butyl rubber, propylene-butadiene rubber, acrylonitrile-butadiene rubber, and acrylonitrile-isoprene rubber. Diene rubber (elastomer), 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 Polyolefin obtained by a multistage polymerization method, polyolefin obtained by dynamically crosslinking a mixture of the rubber (component) mentioned above and a polyethylene resin and / or 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 the multistage polymerization 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 the present invention, the total content of the three components of the above-described polypropylene-based resin, NOR-type hindered amine derivative and thermoplastic elastomer, which are the main components of the flame-retardant resin film, is 80 to 100% by weight of the entire flame-retardant resin film. It is preferable that

  In addition to the above-described components, the flame-retardant resin film of the present invention can contain other synthetic resins and various additives as necessary. For example, heat stabilizers, antioxidants, ultraviolet absorbers. A lubricant, an antiblocking agent, a colorant, and the like can be used, but the content of components other than the above three main components is preferably 20% by weight or less of the entire flame-retardant resin film.

  Examples of the other synthetic resins include styrene-butadiene thermoplastic rubbers such as styrene-butadiene copolymer rubber (SBR) and styrene-butadiene block copolymers, and styrene thermoplastic elastomers such as styrene-isoprene copolymer rubber (these Of the hydrogenated product).

  The flame retardant resin film of the present invention contains 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 polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer. The film contains a flame retardant resin film having a melt flow rate (JIS K7210, 230 ° C., 2.16 kgf) of 40 g / 10 min or more and a tensile breaking elongation of 100% or more.

  Since the flame-retardant resin film of the present invention does not contain a polyvinyl chloride resin or a flame retardant such as a halogen compound, it is possible to suppress the generation of harmful gases during disposal.

  Moreover, the flame-retardant resin film of this invention can be made into a laminated structure as needed. In that case, a resin composition containing 0.5 to 3.0 parts by weight of a NOR type hindered amine derivative with respect to a total of 100 parts by weight of 5 to 95 parts by weight of a polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer, It is preferable that it is 80 to 100 weight% of the whole flame-retardant resin film.

  The flame-retardant resin film of the present invention may contain other additives, adhesives, other synthetic resin layers, and the like, if necessary, but includes 5 to 95 parts by weight of a polypropylene resin and a thermoplastic elastomer. Ingredients other than the resin composition containing 0.5 to 3.0 parts by weight of the NOR type hindered amine derivative with respect to a total of 100 parts by weight of 5 to 95 parts by weight It is preferable that

  In the preferable aspect of this invention, content of the said thermoplastic elastomer 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 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.

  The melt flow rate (JIS K7210, 230 ° C., 2.16 kgf) of the resin composition constituting the flame-retardant resin film of the present invention is 40 g / 10 minutes or more, preferably 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 addition, the flame-retardant resin film of the present invention having a tensile elongation at break (%) (JIS K 7127, 23 ° C., 60% RH, tensile speed 300 mm / min) lower than 100% is not practically used. It is not preferable.

  In a preferred embodiment of the present invention, the film has an oxygen index of 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 thickness of this flame-retardant resin film is 0.03-0.4 mm, More preferably, it is 0.06-0.15 mm. When the thickness of the film is thinner than the above specific value, the film is easily broken, and when the thickness of the film is thicker than the above specific value, the flexibility of the film is impaired.

  Next, the manufacturing method of the flame-retardant resin film of this invention is demonstrated.

The method for producing a flame-retardant resin film of the present invention is based on a NOR type hindered amine derivative 0.5 to 3.0 with respect to a total of 100 parts by weight of 5 to 95 parts by weight of a polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer. It has the process of manufacturing the film containing a weight part, and the process of irradiating a radiation to the obtained film.

  In the process of producing the film, a general polyolefin resin film molding method such as an extrusion molding method such as a T-die extrusion molding method, an inflation molding method, or a calendar molding method is used. As the resin, an extrusion molding machine is suitable. 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.

  In the step of irradiating the film with radiation, the irradiation method is not particularly limited, and a known irradiation apparatus can be used, but the radiation is preferably an electron beam, and the energy of the electron beam is It is preferably 30 to 500 kGy. If the energy of the electric wire is smaller than 30 kGy, flame retardancy cannot be obtained, and if it is larger than 500 kGy, the film strength is insufficient.

  As the electron beam irradiation device, for example, a Cockloft Walton type, a bandegraph type, a resonance transformation type, an insulating core transformer type, a linear type, a dynamitron type, a high frequency type, etc. can be used.

  The flame-retardant resin film of the present invention thus obtained is excellent in mechanical strength and flexibility and has no sticky feeling on the film surface. In addition, since MFR is 40 g / 10 min or more and combines high flame retardancy, particularly in fields requiring high flame retardance such as electric / electronic products, automobiles, and building materials. Preferably used.

  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 1-3, Comparative Examples 1-4>
According to the formulation described in Table 1, Example 1 is a single layer structure, Examples 2-3 and Comparative Examples 1-4 are laminated in the order of the first layer, the second layer, and the third layer 3 It was set as the film of the layer structure. The resin and compounding agent used in each layer are dry blended in a pellet state, and the blended raw materials are put into the 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 and wound by a winder equipped with a cooling roll (cooling roll 700 mm width × φ350 mm, roll temperature 30 ° C.), and accelerated voltage using ELECTRO CURTAIN CB170 (I-Graphics). The films of Examples 1 to 3 and Comparative Examples 1 to 4 were obtained by irradiation with an electron beam at 165 kV.

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

<Evaluation>
(1) The melt flow rate of the resin composition constituting the melt flow rate 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 made into films. X cannot be put to practical use.

(3) Evaluation of flame retardancy A test piece (dimensions: length 130 mm, width 65 mm) is taken from the 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 extract | collected from the film was measured.

(5) Evaluation of Strength According to JIS K 7127, a test piece (dumbbell shown in FIG. H. Under the atmosphere, tensile elongation at break (%) was measured at a tensile speed of 300 mm / min with a tensile tester. Those having a tensile elongation at break lower than 100% are not practically used.

In the examples and comparative examples, the respective resins and compounding agents are specifically as follows.

PP: Homo PP (Nippon Polypro Co., Ltd., Novatec PP MA3U MFR 15.5 g / min)
Elastomer: Olefin-based elastomer (manufactured by Sun Allomer Co., Ltd., Catalloy C200F MFR 6 g / min)
NOR: NOR type hindered amine derivative (FLAMESTAB NOR116FF manufactured by Ciba Japan)
The composition according to the present invention was able to produce a film having a good appearance by extrusion molding, and the obtained film of the present invention was excellent in flame retardancy (Examples 1 to 3). In particular, Example 3 in which the melt flow rate (JIS K7210, 230 ° C., 2.16 kgf) of the resin composition was 55 g / 10 min was found to be more excellent in flame retardancy.

  On the other hand, the films of Comparative Examples 1 and 3 were inferior in flame retardancy, although the strength was excellent. Although the film of Comparative Example 2 was excellent in flame retardancy, it was inferior in strength. In Comparative Example 4, the processability was poor and a film having a good appearance could not be obtained.

Claims (5)

It contains 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 polypropylene resin and 5 to 95 parts by weight of a thermoplastic elastomer , and a melt flow rate (JIS K7210, After the resin composition having a temperature of 230 ° C. and 2.16 kgf) of 1 to 20 g / 10 min is extruded to produce a film, the film is irradiated with radiation to melt flow rate of the resin composition constituting the film ( JIS K7210, 230 degreeC, 2.16kgf) shall be 40 g / 10min or more, and the tensile fracture elongation of this film shall be 100% or more, The manufacturing method of the flame-retardant resin film characterized by the above-mentioned. The method for producing a flame-retardant resin film according to claim 1, wherein a melt flow rate (JIS K7210, 230 ° C, 2.16 kgf) of the resin composition constituting the film is 50 g / 10 min or more. The method for producing a flame-retardant resin film according to claim 1 or 2, wherein the film has an oxygen index of 26.0 or more. The method for producing a flame-retardant resin film according to claim 1 , wherein the radiation is an electron beam. The method for producing a flame-retardant resin film according to claim 4 , wherein the energy of the electron beam is 30 to 500 kGy.