JP6418521B2 - Polypropylene resin molding material - Google Patents

Description

  The present invention relates to a polypropylene resin molding material.

  Polypropylene resin has excellent electrical properties, water resistance, and chemical resistance. Therefore, injection molded products made of polypropylene resin are used for automobile parts, electrical products, various industrial products such as containers for transportation and storage, medical equipment, daily necessities, etc., hollow molded products are used for food and chemical containers, and extruded products are used for various packaging. Widely used for film, string, pipe, sheet and so on.

  However, since a polypropylene resin is easily combusted, a flame retardant is blended to make it flame retardant (see, for example, Patent Document 1). The flame-retardant polypropylene resin molding material described in Patent Document 1 contains polypropylene, an ultraviolet absorber, and a brominated phosphate as a flame retardant.

Japanese Patent Laid-Open No. 10-67895

  However, since brominated flame retardants such as brominated phosphates are likely to change color, molded articles containing such flame retardants are likely to change color. In order to improve the light resistance, an antioxidant is further added to the propylene resin molding material. However, particularly when the molded product is used as an exterior part, there remains a problem in weather discoloration. It was.

  This invention is made | formed in view of said point, and it aims at providing the polypropylene resin molding material which can make a flame retardance and weather resistance discoloration compatible.

The polypropylene resin molding material according to the present invention is
Polypropylene resin,
Brominated flame retardants,
With antimony trioxide,
A phosphite antioxidant,
A hindered phenolic antioxidant,
Containing octadecyl phosphate,
For 100 parts by mass of the polypropylene resin,
5 to 15 parts by mass of the brominated flame retardant,
1 to 5 parts by mass of the antimony trioxide,
0.05 to 0.5 parts by mass of the phosphite antioxidant,
The hindered phenol antioxidant is 0.05 to 0.5 parts by mass.

For 100 parts by mass of the polypropylene resin,
It is preferable that the said octadecyl phosphate is 0.01-0.5 mass part.

  According to the present invention, polypropylene resin, bromine-based flame retardant, antimony trioxide, phosphite-based antioxidant, and hindered phenol-based antioxidant are contained in predetermined amounts, respectively, and further contain octadecyl phosphate. By doing so, both flame retardancy and weather resistance discoloration can be achieved.

  Embodiments of the present invention will be described below.

  The polypropylene resin molding material of this embodiment contains a polypropylene resin, a brominated flame retardant, antimony trioxide, a phosphite antioxidant, a hindered phenol antioxidant, and octadecyl phosphate.

  The polypropylene resin is a thermoplastic resin obtained by polymerizing propylene, and is not particularly limited as long as it is used for molding.

  The brominated flame retardant is not particularly limited. For example, Pyroguard series ("SR-102", "SR-105", "SR-245", "SR-250", "SR-250", "Daiichi Kogyo Seiyaku Co., Ltd.") SR-460B "," SR-600A "," SR-720 "," SR-742 "," SR-743 "," SR-770 "), Tosoh Corporation Frame Cut Series (" 110R "(Decabromo) Diphenyl ether), "120G" (tetrabromobisphenol A), "121K" (TBBA-bis (2,3-dibromopropyl ether)), "122K" (TBBA-bis (allyl ether))), manufactured by Albemarle Japan SAYTEX series (“CP-2000” (tetrabromobisphenol A), “8010” (ethylene bis (pentabro Phenyl)), “BT-93 / W” (ethylenebistetrabromophthalimide), “HP-7010” (brominated polystyrene), “HP-3010” (brominated polystyrene), “HP-900” (hexabromocyclo) Dodecane), “102E” (decabromodiphenyl oxide), “120” (tetradecabromodiphenoxybenzene), “BC-48” (tetrabromocyclooctane), “BCL-462” (dibromomethyl-dibromocyclohexane), “HP-800” (TBA-bisdibromopropyl ether), “RB? 49” (tetrabromophthalic anhydride)), Great Lakes series (“pdbs-80” (polydibromostyrene) manufactured by Chemtura Japan, “PBS- 64HW "(polybromostyrene)," P "T4" (tetrabromophthalic anhydride), "DP-45" (tetrabromophthalic acid ester), "CD-75P" (hexabromocyclododecane), "BA-59P" (tetrabromobisphenol A), "PE-68 (Tetrabromobisphenol A bis (dibromopropyl) ether), "BC-52" (phenol-terminated tetrabromobisphenol carbonate oligomer), "BC-58" (phenol-terminated tetrabromobisphenol carbonate oligomer), "PH-73FF" ( 2,4,6-tribromophenol), “FF-680” (bis (tribromophenoxy) ethane), “DE-83R” (decabromodiphenyl oxide)), Teijin Limited Fireguard (“FG-2000”) (Tetrabromobisphenone A (TBA)), “FG-3000” (TBA bisbromoethyl ether), “FG-3100” (TBA bisbromopropyl ether), “FG-3200” (TBA bisallyl ether), “FG-3600” (TBA bisethoxylate), "FG-7000" (TBA carbonate oligomer), "FG-7500" (TBA carbonate oligomer), "FG-8500" (TBA carbonate oligomer)).

  The brominated flame retardant is 5 to 15 parts by mass with respect to 100 parts by mass of the polypropylene resin. When the brominated flame retardant is less than 5 parts by mass, the flame retardancy of the molded product is lowered. For example, the flame resistance grade of UL94 standard is reduced to HB. When the brominated flame retardant exceeds 15 parts by mass, the flame retardancy of the molded article is improved, but the weather discoloration may be lowered, which is not preferable in terms of cost. For example, regarding the flame retardancy of molded articles, the flame retardancy grade of UL94 standard is improved to V-0, but it reaches a peak.

The antimony trioxide (ATO, Sb ₂ O ₃ ) is a kind of oxide of antimony.

  The antimony trioxide is 1 to 5 parts by mass with respect to 100 parts by mass of the polypropylene resin. When the antimony trioxide is less than 1 part by mass, the flame retardancy of the molded product is lowered. For example, the flame resistance grade of UL94 standard is reduced to HB. When the antimony trioxide exceeds 5 parts by mass, the flame retardancy of the molded product is improved, but it is not preferable in terms of cost. For example, the flame retardancy grade of UL94 standard is improved to V-0, but it reaches a peak.

  In this embodiment, the brominated flame retardant and the antimony trioxide are used in combination to improve the flame retardancy of the molded product. When using only the brominated flame retardant to improve the flame retardancy rating of UL94 standard to V-0, the brominated flame retardant needs to be 20 parts by mass or more with respect to 100 parts by mass of the polypropylene resin. Become. However, in this case, the brominated flame retardant exceeds 15 parts by mass, and the weather discoloration resistance of the molded product is likely to deteriorate. That is, the change in color tone (color difference) of the molded product before and after the weather resistance test increases.

  The phosphite antioxidant is not particularly limited. For example, 3,9-bis (2,6-di-tert-butyl-4-methylphenoxy) -2,4,8,10-tetraoxa-3, 9-Diphosphaspiro [5.5] undecane (3,9-Bis (2,6-di-tert-butyl-4-methylphenoxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [ 5.5] undecane), 3,9-bis (octadecyloxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane (3,9-Bis (octadecyloxy) -2 , 4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane), 2,2'-methylenebis (4,6-di-tert-butylphenyl) -2-ethylhexyl phosphite (2,2'- Methylenebis (4,6-di-tert-butylphenyl) 2-ethylhexyl phosphite), Tris (2,4-di-tert-butylphenyl) phosphite Examples thereof include phosphite and tris (nonylphenyl) phosphite.

  The phosphite antioxidant is 0.05 to 0.5 parts by mass with respect to 100 parts by mass of the polypropylene resin. When the phosphite-based antioxidant is less than 0.05 parts by mass, the weather resistance discoloration of the molded product is lowered. That is, the change in color tone (color difference) of the molded product before and after the weather resistance test increases. When the amount of the phosphite antioxidant exceeds 0.5 parts by mass, the deterioration of the weather discoloration of the molded product is suppressed, but the effect reaches a peak.

  The hindered phenol-based antioxidant is not particularly limited. For example, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2 , 4,6 (1H, 3H, 5H) -trione (1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione), stearyl 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 6- [3- (3-tert-butyl-4-hydroxy-5) -Methylphenyl) propoxy] -2,4,8,10-tetra-t-butylbenz [d, f] [1,3,2] dioxaphosphine, 3,9-bis {2- [3- ( 3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8,10-te Raoxaspiro [5.5] undecane (3,9-Bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8, 10-tetraoxaspiro [5.5] undecane), 1,3,5-tris (3,5-di-tert-butyl-4-hydroxyphenylmethyl) -2,4,6-trimethylbenzene (1,3,5-tris (3,5-di-tert-butyl-4-hydroxyphenylmethyl) -2,4,6-trimethylbenzene).

  The hindered phenol-based antioxidant is 0.05 to 0.5 parts by mass with respect to 100 parts by mass of the polypropylene resin. When the hindered phenol-based antioxidant is less than 0.05 parts by mass, the weather discoloration resistance of the molded product is lowered. That is, the change in color tone (color difference) of the molded product before and after the weather resistance test increases. When the amount of the hindered phenol antioxidant exceeds 0.5 parts by mass, the deterioration of the weather discoloration of the molded product is suppressed, but the effect reaches a peak.

  Only with the phosphite antioxidant and the hindered phenol antioxidant, there is a limit in improving the weather discoloration of the molded product, but by incorporating the octadecyl phosphate into the polypropylene resin molding material, Due to the synergistic effect of these components, the weather discoloration resistance of the molded product can be further improved.

  In particular, the octadecyl phosphate is preferably 0.01 to 0.5 parts by mass and more preferably 0.03 to 0.4 parts by mass with respect to 100 parts by mass of the polypropylene resin. Thereby, the change (color difference) of the color tone of the molded product before and after the weather resistance test can be further reduced.

  The polypropylene resin molding material may further contain talc, an antistatic agent, titanium oxide, and an adsorbent. When the talc is contained, the talc is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the polypropylene resin. When the antistatic agent is contained, the antistatic agent is preferably 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the polypropylene resin. When the titanium oxide is contained, the titanium oxide is preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the polypropylene resin. When the adsorbent is contained, the adsorbent is preferably 0.1 to 2.0 parts by mass with respect to 100 parts by mass of the polypropylene resin.

  In particular, the adsorbent is preferably contained in the polypropylene resin molding material. When the polypropylene resin molding material contains the adsorbent, when the polypropylene resin molding material is heated and melted into a plasticized state in a cylinder of an injection molding machine, mainly from the brominated flame retardant The adsorbent can adsorb the generated low molecular weight compound. The low molecular compound is, for example, an organic substance having a benzene ring. As described above, the adsorbent adsorbs the low molecular weight compound, thereby suppressing the low molecular weight compound from adhering (bleeding) to the surface of the mold cavity during the injection molding. When a low molecular weight compound adheres to the surface of the cavity, the low molecular weight compound cools and solidifies to become white crystals, so that the surface of the cavity becomes cloudy, for example, fine irregularities on the surface of the cavity are highly accurate. It becomes difficult to transfer to the surface of the molded product. Even if the surface of the mold cavity is a mirror surface, the surface of the molded product is not glossy.

Examples of the adsorbent include zeolite (crystalline aluminosilicate). The zeolite preferably has a SiO ₂ / Al ₂ O ₃ ratio (silica / alumina ratio) of 5 or more. Thereby, the adsorption effect of a low molecular compound becomes high. The higher the SiO ₂ / Al ₂ O ₃ ratio, the more advantageous is the adsorption of low-molecular compounds at high temperatures (for example, molding temperature). The upper limit of the SiO ₂ / Al ₂ O ₃ ratio is 2200, for example. The pore diameter of the zeolite is preferably 0.5 nm or more, and the upper limit is, for example, 1.0 nm.

  The zeolite is not particularly limited. For example, HSZ series manufactured by Tosoh Corporation (“642NAA”, “640HOA”, “690HOA”, “840HOA”, “891HOA”, “930NHA”, “940HOA”, “980HOA”) Can be mentioned.

  The said polypropylene resin molding material can be manufactured as follows, for example. Polypropylene resin, bromine flame retardant, antimony trioxide, phosphite antioxidant, hindered phenol antioxidant, octadecyl phosphate, talc, antistatic agent, titanium oxide mixed with tumbler if necessary 2 Pass through a shaft extrusion kneader. The strand coming out of the biaxial extrusion kneader is immediately cooled in a cooling bath, and then the strand is cut with a pelletizer, whereby a granular polypropylene resin molding material (pellet) can be produced.

  A molded product can be produced by, for example, injection molding the polypropylene resin molding material. That is, the molded product can be manufactured by heating and melting the polypropylene resin molding material to a plasticized state, applying pressure to a previously closed mold cavity, injection filling, and then solidifying by cooling.

  The molded article contains a predetermined amount of a polypropylene resin, a brominated flame retardant, antimony trioxide, a phosphite antioxidant, and a hindered phenol antioxidant, respectively, and further contains octadecyl phosphate. Thus, both flame retardancy and weather resistance discoloration can be achieved. Since the molded article is particularly excellent in weather resistance discoloration, it is suitably used as an exterior part and also as an interior part.

  Hereinafter, the present invention will be specifically described by way of examples.

(Components of polypropylene resin molding material)
The components used for the production of the polypropylene resin molding material are as follows.

・ Polypropylene resin ("J108M" manufactured by Polyplastics Co., Ltd.)
-Brominated flame retardant ("SR-743N" manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
・ Antimony trioxide (“PATOX-M” manufactured by Nippon Seiko Co., Ltd.)
-Phosphite-based antioxidant ("PEP-36" manufactured by ADEKA Corporation (3,9-Bis (2,6-di-tert-butyl-4-methylphenoxy) -2,4,8,10-tetraoxa-3 , 9-diphosphaspiro [5.5] undecane))
・ Hindered phenolic antioxidant (“AO-20” manufactured by ADEKA Corporation (1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine- 2,4,6 (1H, 3H, 5H) -trione))
・ Octadecyl phosphate (“AX-71” manufactured by ADEKA Corporation)
-Talc ("PKC" manufactured by Hayashi Kasei Co., Ltd.)
・ Antistatic agent (Miyoshi Oil & Fats Co., Ltd. “K-220”)
・ Titanium oxide ("RTC-30" manufactured by Tioxide)
・ Adsorbent (“HSZ 891HOA” manufactured by Tosoh Corporation)
(Manufacture of polypropylene resin molding materials)
The above components were blended in the blending amounts (parts by mass) shown in Table 1, mixed for 10 minutes with a tumbler, and passed through a twin-screw extrusion kneader. The cylinder temperature of the biaxial extrusion kneader was set to be 190 ° C. near the die and 180 ° C. near the inlet. It was 220 degreeC when the temperature of the strand immediately after leaving a biaxial extrusion kneader was measured with the non-contact-type thermometer. The strand coming out of the biaxial extrusion kneader was immediately cooled in a cooling tank, and then the strand was cut into granules having a length of 2 to 4 mm with a cutter to obtain a pellet of a polypropylene resin molding material.

(Manufacture of molded products)
The above-mentioned polypropylene resin molding material pellets were not dried. Then, using a 100-ton horizontal injection molding machine, the above-mentioned polypropylene resin molding material is injected into a film gate type injection molding die, and molding as a test piece for evaluating weather discoloration and flame retardancy described later. Manufactured. The cylinder temperature of the injection molding machine was set to 190 ° C. near the head, 190 ° C. near the material inlet, and the mold temperature was set to 60 ° C.

(Weather discoloration)
Before the weather resistance test, the color tone of the test piece (60 mm × 60 mm × 2 mm) was measured with a spectral color difference meter (“SE 2000” manufactured by Nippon Denshoku Industries Co., Ltd.).

Then, the weather resistance test was done about said test piece. Specifically, after irradiating UV with a 400 W mercury lamp for 24 hours so that the UV illuminance on the surface of the test piece becomes 3000 μW / cm ² (3 mW / cm ² ) in a 90 ° C. constant temperature machine, It was left for 24 hours in a dark place with a humidity of 85%. After the weather resistance test, the color tone of the test piece was measured again with a spectral color difference meter (“SE 2000” manufactured by Nippon Denshoku Industries Co., Ltd.).

  The difference in color tone before and after the weather resistance test was defined as a color difference (ΔE), and weather discoloration resistance was evaluated based on this color difference.

(Flame retardance)
The test piece (thickness 0.8 mm) was subjected to a UL94 standard combustion test to evaluate flame retardancy.

(Gloss of molded products)
As described above, the molded product was continuously manufactured by 100 shot injection molding. The gloss (gross) of the surface of the 100th shot molded product was measured according to ASTM D2457-1970.

  As is clear from Table 1, each of the comparative examples has poor evaluation of either flame retardancy or weather discoloration, whereas each example confirms that both flame retardancy and weather discoloration can be achieved. It was done. Moreover, in Example 6, since the adsorbent was contained in the molded product, it was confirmed that a molded product having higher gloss than that of the other examples and comparative examples was obtained.

Claims (2)

Polypropylene resin,
Brominated flame retardants,
With antimony trioxide,
A phosphite antioxidant,
A hindered phenolic antioxidant,
Octadecyl phosphate ,
Containing an adsorbent ,
For 100 parts by mass of the polypropylene resin,
5 to 15 parts by mass of the brominated flame retardant,
1 to 5 parts by mass of the antimony trioxide,
0.05 to 0.5 parts by mass of the phosphite antioxidant,
0.05 to 0.5 parts by mass of the hindered phenol-based antioxidant ,
The polypropylene resin molding material, wherein the adsorbent is 0.1 to 2.0 parts by mass . For 100 parts by mass of the polypropylene resin,
The polypropylene resin molding material according to claim 1, wherein the octadecyl phosphate is 0.01 to 0.5 parts by mass.