JPS6395266A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition by incorporating a flammable syn thetic resin with a modified red phosphorus which is not subject to hydrolysis even in the presence of water leading to suppression of the generation of toxic and odoriferous phosphine gas, thus enabling the provision of flame-retardancy to be carried out without deteriorating the workplace environment. CONSTITUTION:The objective composition can be obtained by incorporating (A) 100pts.wt. of a flammable synthetic resin (thermoplastic or thermosetting one) with (B) 0.5-50pts.wt. on a phosphorus basis, of a modified red phosphorus with the particles coated with electroless plating film. Said film is made of a substance selected from Ni, Cu, Co, Fe, Zn, Mn, and alloys thereof.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a flame-retardant resin composition, and particularly to a modified flame-retardant resin composition in which a combustible synthetic resin such as a thermoplastic resin or a thermosetting resin is coated with an electroless plating film. This relates to a flame-retardant resin composition containing red phosphorus.

[Prior Art] Conventionally, the uses of various synthetic resin molded products have been expanding with increasing diversity, but at the same time, flame retardant requirements for the molded products have become increasingly strict.

It is well known that red phosphorus is used as a typical additive in making synthetic resins flame retardant.

However, since red phosphorus generates phosphine with an unpleasant odor when hydrolyzed, there is a problem in blending it as it is into a resin. Therefore, many proposals have been made for stabilized red phosphorus that is modified red phosphorus.

For example, modified red phosphorus coated with thermosetting resin (Japanese Unexamined Patent Publication No. 5
1-105996), modified red phosphorus in which the surface of red phosphorus is converted into a metal phosphide and then coated with a thermosetting resin (JP-A-52-125489), or red phosphorus is converted into a metal phosphide and then coated with a thermosetting resin; Modified red phosphorus coated with a triple layer of hydroxide, etc. and an inorganic or organic coating agent (Japanese Patent Application Laid-open No. 55
-10462) etc. are representatively known.

[Problems to be Solved by the Invention] As mentioned above, many proposals have been made for stabilizing red phosphorus through modification, but all of them have advantages and disadvantages, and still have some important problems. In particular, red phosphorus is easily hydrolyzed in the presence of moisture and is accompanied by the generation of phosphine gas, which is odorous and toxic even in a very small amount, so it is extremely difficult to completely suppress the generation of this gas.

In particular, thermoplastic resins require processing and molding temperatures of 200°C or higher, sometimes exceeding 300°C due to demands such as improved workability. Since the suppression of phosphine gas was insufficient, it could hardly be put to practical use.

In order to virtually completely suppress the generation of phosphine gas that accompanies the decomposition of red phosphorus, the present invention was developed through extensive research searching for various stabilization methods. As a result, it was surprisingly found that stable red phosphorus powder could be obtained, and it could be applied to not only thermosetting resins but also thermoplastic resins without sacrificing flame retardancy. The present invention was completed based on the finding that the present invention can be used for various purposes.

[Means for solving the problem] and [Operation] That is, the gist of the present invention is to blend modified red phosphorus in which the surface of red phosphorus particles is coated with an electroless plating film into a flammable synthetic resin. The present invention relates to a flame-retardant resin composition characterized by:

The present invention will be explained in detail below.

The flammable synthetic resin that can be used in the present invention is a flammable synthetic resin that is required to be flame retardant when used, and may be either a thermosetting resin or a thermoplastic resin. Further, the combustible synthetic resin can be used, for example, as various molding materials, paints, adhesives, etc., and the manner is not particularly limited.

Examples of the thermosetting resin include phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, silicone resin, diacrylic phthalate resin, and polyurethane resin.

Examples of thermoplastic resins include polyethylene, polyalpha-olefins such as polypropylene, copolymers with other monomers containing at least alpha-olefins, polystyrene, methacrylic resins, styrene-acrylonitrile copolymers (AS resins), etc. ), acrylonitrile-tutadiene-styrene resin (ABS resin), polyvinyl chloride, fluororesin, polyamide, polyimide, polycarbonate, polyacetal, thermoplastic polyester, cellulose acetate (cellulose resin), polysulfone Ig polyimide, polyphenylene oxide , polystyrene ionomer resin, etc.

Next, the modified red phosphorus that can be effectively blended into the flammable synthetic resin as a flame retardant refers to stabilized red phosphorus in which the surface of red phosphorus particles is coated with an electroless plating film, and the plating film is: There are no particular restrictions on the metal as long as it can form an electroless plating film, but especially Fe, old metal,
A metal plating film selected from Co, Cu, Zn, Mn, or an alloy thereof is practical, and among these, Zn and its alloy are particularly preferred.

The modified red phosphorus in the present invention can be produced by a conventional known electroless plating method.

Among these electroless plating methods, modified red phosphorus is produced by gradually adding an electroless plating solution to an aqueous suspension of red phosphorus to form a plating film on the surface of red phosphorus particles. Preferably, phosphorus is used.

In addition, in the electroless plating method, when sodium hypophosphite or alkali borohydride or the like is used as a reducing agent, depending on the conditions, some phosphorus or boron may constitute the film composition.

Of course, such a film is also acceptable in the present invention.

Furthermore, in the case of a film that is easily oxidized, such as a film of Fe or its alloy, the surface of the film may be oxidized over time to form an oxide film, but in the present invention, red phosphorus particles are initially applied to the plating film. If it forms, it is included in the modified red phosphorus, regardless of its change over time.

The reason for this is that even if there is some change in the surface, it is not a problem in stabilizing red phosphorus, and in fact, if it is necessary to avoid the conductive properties of the metal film, it is necessary to intentionally replace the oxide film with metal plating. This is because it may be necessary and preferable to form it on the film.

The amount of the plating film coated varies depending on the use of the modified red phosphorus, the type of metal, etc., but in most cases it is desirable to be in the range of 0.5 to 50% by weight based on the total weight.

The reason for this is that if the content is less than 0.5% by weight, the suppression of phosphine gas is incomplete, and if it exceeds 50% by weight, it is inappropriate from a practical standpoint.

In particular, in the present invention, when the modified red phosphorus is used as a flame retardant for various flammable synthetic resins, the modified red phosphorus is used as P for 100 parts by weight of the flammable synthetic resin.
．． A range of 5 to 50 parts by weight is suitable, preferably 0.5 to 15 parts by weight, while a range of 5 to 50 parts by weight is suitable for use as a flame-retardant electrically conductive material.

The modified red phosphorus in the present invention can be easily identified by 1W4 microscopic observation as compared to the original red phosphorus because the metallic luster is uniformly formed on the particle surface.

The modified red phosphorus used in the present invention is stabilized red phosphorus that almost completely suppresses the generation of phosphine gas, and although the details of the reason for this are unknown, it is probably because red phosphorus itself is a highly reducing base material. Therefore, compared to electroless plating of other base materials,
It seems that the plating film was formed more firmly.

Furthermore, the modified red phosphorus in the present invention can be used in combination with other inorganic or organic flame retardants.

Inorganic flame retardants include magnesium, aluminum,
Examples include hydroxides such as zirconium, antimony oxide, etc. Organic flame retardants include various phosphate esters,
It can be appropriately selected from phosphite esters, organic tin compounds, and the like.

In addition, in the present invention, the flame retardant resin composition may contain other resin additives (1), which are usually blended as necessary depending on the purpose of use, such as plasticizers, lubricants, stabilizers, fillers, colorants, and antioxidants. Alternatively, an ultraviolet inhibitor or the like may be appropriately added.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

Examples 1 to 13 (1) Preparation of modified red phosphorus O Samples 1 to 5 100 g of red phosphorus powder with a particle size of 44 gm or less and an average particle size of 24 μm was added at 0.1 g/i' palladium chloride dilute hydrochloric acid solution 1
I! The mixture was stirred for about 5 minutes, filtered, and then repulped, filtered, and catalyzed.

The red phosphorus powder that has been catalyzed in this way is poured into an aqueous solution lI2 of various complexing agents shown in Table 1, thoroughly dispersed, and the liquid temperature is heated to 80°C to form an aqueous suspension. Prepared.

Next, the electroless plating solution shown in Table 2 was divided into solution a and solution b, and 41■P was individually and simultaneously added to each solution for 5 sins.
The mixture was added to the above aqueous suspension while stirring at an addition rate of 1/2 min, and plating was performed under each condition.

In all experiments, after adding the entire amount of the plating solution, stirring was continued while maintaining the temperature at 80° C. until the generation of hydrogen stopped, followed by filtration, repulp washing, filtration, and drying.

When the obtained red phosphorus plating powder was observed under a microscope, it was found that the surfaces of the red phosphorus particles were completely coated with a uniform film with metallic luster. Further, as a result of measuring thin film X-ray diffraction images of the skin and film using a thin film X-ray diffraction measuring device, it was confirmed that all the precipitates were nickel metal.

Table 1 Table 2 Table O Samples 6 to 11 100 g of red phosphorus powder with a particle size of 44 ps or less and an average particle size of 244 m was mixed with 2 g/R of aminopropyltriethoxysilane.
and palladium chloride 0.1g/i' mixed solution l
I! After stirring for about 15 minutes to disperse well,
? The mixture was filtered for 7 hours, dried, moisture was completely removed, and catalyzed. 10g of red phosphorus powder pretreated in this way #sodium tartrate aqueous solution l! A dispersion treatment was carried out so that substantially no agglomerates were present, and the temperature was raised to 75° C. to prepare an aqueous suspension with a plf of 7.0.

Next, the electroless plating solution shown in Table 3, a.

According to Table 4, first add the drugs A and B individually and simultaneously at a dropping rate of 5 m12/min, then add the A solution 30 seconds before the end of dropping A solution. The same dropwise rate was added to the above suspension under stirring. After adding the entire amount (including the case of liquid addition), stirring was continued while maintaining the temperature at 75°C until hydrogen generation stopped.
After filtration, repulp washing, and filtration, it was dried.

When all of the Example products were observed under a microscope, it was found that the red phosphorus particles had a uniform metal coating on the entire surface.

Table 3 Table 4 ○ Sample No. +2 100 g of red phosphorus powder with a particle size of 44 μl or less and an average particle size of 24 μl was added to 0.1 g of #palladium chloride dilute hydrochloric acid solution II
! After stirring for about 5 minutes, the mixture was subjected to catalytic treatment by filtration, repulping, and RP filtration.

The red phosphorus powder catalyzed in this way was added to 1 g of an aqueous solution of 20 g of sodium tartrate, thoroughly stirred and dispersed, and heated to the liquid temperature of 80°C to prepare an aqueous suspension with a pH of 7.0. .

Next, copper sulfate 196g/i) aqueous solution (liquid a) 105
vj>, sodium hypophosphite 208g/i) and sodium hydroxide 118g/R mixed aqueous solution (liquid B)
105 mR were each individually and simultaneously added to the above aqueous suspension under stirring at an addition rate of 51 ρ/min.

After adding the entire amount, stirring was continued while maintaining the temperature at 80''C until the generation of hydrogen stopped, followed by filtration, repulp washing, filtration, and drying.

When the obtained powder was observed under a microscope, it was confirmed that the entire surface of the red phosphorus particles was coated with a uniform copper film.

0 Sample No. 13 Red phosphorus powder i with a particle size of 44 μm or less and an average particle size of 24
oo g to aminopropyltriethoxysilane 2g/R
and a mixed solution li consisting of palladium chloride 0.1 g/J
! After stirring for about 15 minutes to ensure good dispersion,
The mixture was filtered and dried to completely remove moisture and then subjected to catalytic treatment.

10 g of the red phosphorus powder pretreated in this way was added to an aqueous solution Ifl containing 30 g/i' of sodium tartrate, thoroughly dispersed, and heated to 85°C to form an aqueous suspension with a pH of 5.0. was prepared.

Next, 249 g/i) ferrous sulfate aqueous solution (liquid a),
and 237g/R sodium hypophosphite and 134g/
J) Mixed aqueous solutions of sodium hydroxide concentration (liquid b), each 41sR, were individually and simultaneously added at a dropwise rate of 51Il1 min to the aqueous suspension under stirring.

After adding the entire amount, stirring was continued while maintaining the temperature at 85°C until hydrogen generation stopped. Then, filtration, repulp washing, and Tp
After drying.

When the obtained powder was observed using an m-microscope, it was found that the surface of the red phosphorus particles was entirely covered with a uniform metal film, and furthermore, the particles had a film that appeared to be iron oxide partially thereon.

(2) Preparation of 84 fat composition A mixture of the following composition was placed in a mold (12.7 m x 12.75
The epoxy resin molded product was prepared by pouring it into a molded epoxy resin and heating it at 100° C. for 6 hours to harden it.

No phosphine odor occurred during the preparation of this test piece.
Detection tube (gastic detection tube: detection limit 0, O4ppm
(manufactured by Hokuyo Sangyo ■) could not detect it.

Sample As red phosphorus 1 Horn (3)
2I11 standard method and its results 1. Measurement of the amount of metal coated A certain amount of metal-coated red phosphorus from each sample was collected, the metal coating was dissolved using nitric acid, and the metal ions in the solution were analyzed by chelate titration method. The metal coating adhesion was determined. The results are shown in Table 5. 2. Measurement of specific resistance of metal-coated red phosphorus powder The resistance value of each sample of metal-coated red phosphorus powder was measured by a four-probe method. The results are shown in Table 5.

3. Measuring the amount of phosphine generated from metal-coated red phosphorus powder. 0.5 g of a sample was stored in a constant temperature and humidity chamber at a temperature of 30°C and a relative humidity of 83% for 48 hours, and heated in N2 gas (1
50°C, 3 hours).

The generated PII3i was measured using a gas chromatograph and converted into the amount (gg) of generated Pl+ per Ig of sample. The results are shown in Table 5.

4. #Flame resistance test The resin composition was measured according to the flame resistance test method A of JIS K-6911. The results are shown in Table 5. The resin composition (blank) without red phosphorus was labeled as "flammable."

Comparative Example 1 In the resin composition of Example 1, as samples, thermosetting resin coated red phosphorus (commercial product A, itself phosphine generation amount is 5 ppm) and alumina coated red phosphorus (commercial product B, itself phosphine generation amount is 5 ppm). The amount is 3-7p
An epoxy resin molded body was prepared in the same manner as in Example 1 except that pm) was used, and the flame resistance test of the molded body was conducted.

As a result, all of them had a phosphine odor, and as a result of the measurement, 0.3 to 1.5 ppm of phosphine was detected.

Examples 14 to 22 Resin compositions (Table 6 shows ) 10
1 part by weight of a curing catalyst of methyl ethyl ketone peroxide with a weight of 55% per 0 weight ψ part and an appropriate amount of cobalt naphthenate were mixed uniformly and formed into a mold (12,7*m
Pour into 12.7m5 x 127mm) at 1000C.
The mixture was heated for 2 hours and cured to prepare a polyester resin molded article.

No phosphine odor occurred during the preparation of this test piece.
Detection tube (gastic detection tube: detection limit 0.04pp+s
, manufactured by Kitazawa Sangyo $1) could not be detected.

Further, the obtained test piece was subjected to a heat resistance test using the measuring method shown in Example 1 above. The results are shown in Table 6.

Example 23 1.4-polybutadiene polyol (molecular weight 2800)
Modified red phosphorus (sample No. 1) per 100 parts by weight
) 10 parts by weight, 50 parts by weight of zirconium hydroxide, N,
Homogeneous mixture of 15 parts by weight of N-bis(2-hydroxypropyl)-aniline and 20 parts by weight of process oil 10
15 parts by weight of modified liquid 4,4'-diphenylmethane diisocyanate (NGO equivalent: 145) was mixed with 0 parts by weight, and the mixture was cured by heating at 65°C for 14 hours to obtain a test piece (10 parts by weight).
m■X 10m■×100■■) was created.

In this preparation, no phosphine odor was produced at all, and no phosphine odor was detected in the measurement using a detection tube.

Next, the flame resistance of this test piece was measured by the measuring method shown in Example 1 above, and it showed good flame retardancy.

Examples 24 to 32 Various thermoplastic resin compositions having the formulations shown in Table 7 were prepared,
After heating at 180 to 270°C and mixing with two rolls for 10 minutes, a test piece (12.7mm x 3m x 12.7+a
m) was prepared and tested for flame resistance.

No phosphine odor occurred during the preparation of this test piece.
Detection tube (gastic detection tube: detection limit 0, O4ppm
(manufactured by Hokuyo Sangyo ■) could not detect it.

Further, a heat resistance test was conducted on the obtained test piece.

The results are shown in Table 7.

Comparative Example 2 The same method as in Example 28 was used except that Jingji's thermosetting resin coated red phosphorus (commercial product A) and alumina coach ink red phosphorus (commercial product B) were used as samples for the polystyrene in Example 28. A polystyrene resin molded body was prepared, and a flame resistance test was conducted on the molded body.

As a result, all of them had a phosphine odor, and as a result of the measurement, 1 to 5 ppm of phosphine was detected.

[Effects of the Invention] As explained above, in the Kaiga red phosphorus of the present invention, the surface of the red phosphorus particles is coated with an electroless plating film, and the red phosphorus particles are shielded from the outside, so they cannot be used in the presence of moisture. Hydrolysis reaction is suppressed, and the generation of toxic and foul-smelling phosphine gas is completely prevented.

This modified red phosphorus can exert its inherent flame retardant effect on combustible resins without sacrificing anything, so the flame retardancy of various synthetic resins blended with it is as good as before. It is something that

In particular, it is of great industrial significance that it is possible to make flame retardant mature plastic fence fat, which is processed at high temperatures, without causing any problems in the working environment.

Furthermore, when a large amount of modified red phosphorus with a high plating coverage is blended into a resin, a characteristic resin composition having flame retardant and electrically conductive properties can be obtained, so it can be expected to be used for that purpose.

Claims (5)

[Claims] (1) A flame-retardant resin composition comprising a flammable synthetic resin mixed with modified red phosphorus in which the surface of red phosphorus particles is coated with an electroless plating film. (2) The flame-retardant resin composition according to claim 1, wherein the flammable synthetic resin is a thermoplastic resin. (3) The flame-retardant resin composition according to claim 1, wherein the flammable synthetic resin is a thermosetting resin. (4) Electroless plating film is Ni, Cu, Co, Fe, Z
The flame-retardant resin composition according to claim 1, which is a metal plating film selected from n, Mn, or an alloy thereof. (5) Modified red phosphorus per 100 parts by weight of flammable synthetic wood,
The flame-retardant resin composition according to claim 1, which contains 0.5 to 50 parts by weight of P.