JP2001052527A - Non-halogen flame retardant resin composition and molding product using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To specify specific gravity, oxygen index, and the content of heavy metals, to provide the flame retardancy same as PVC, and to separate from PVC by specific gravity by adding a flame retardant material having a maximum particle size smaller than a specified value to polyolefinic resin. SOLUTION: A flame retardant material having a maximum particle size <=50 μm is added to polyolefinic resin, and a non-halogen flame retardant resin composition having a specific gravity <=1.14, an oxygen index >=24 and a content of heavy metals <0.1 wt.% is obtained. As the flame retardant material, powder of a hydrous inorganic compound such as magnesium hydroxide or aluminum hydroxide with maximum particle size adjusted is preferable. The content of the hydrous inorganic compound is preferable to be 5-50 pts.wt. based on 100 pts.wt. polyolefinic resin, more preferable to be 35-45 pts.wt. As the flame retardant material, by including silicon powder with adjusted particle size in the hydrous inorganic compound, flame retardancy is enhanced, and the specific gravity of the composition is adjusted by changing the ratio of the hydrous inorganic compound and the silicon powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has the same flame retardancy as a polyvinyl chloride (PVC) composition, and has a specific gravity of PVC.
The present invention relates to a non-halogen flame-retardant resin composition which is smaller than the composition, can be separated by specific gravity, does not contain halogen and can be incinerated, and a molded article using the same.

[0002]

2. Description of the Related Art PVC compositions are widely used in wire coatings, tubes, tapes, packaging materials, building materials, etc. because of their good electrical insulation and self-extinguishing flame retardancy. Incidentally, since the PVC composition contains chlorine (Cl) which is a halogen, a corrosive gas such as HCl or a toxic gas such as dioxin is generated during combustion. Therefore, various PVC
There was a problem that when products became waste, they could not be incinerated. Therefore, at present, landfill disposal is used. However, Pb-based stabilizers are often used as additives in PVC compositions, and there is also a problem that this is eluted into soil and the like, and it is difficult to dispose of them as industrial waste. It is becoming.

[0003]

On the other hand, PVC
If a halogen-free polyethylene (PE) or polypropylene (PP) is used as a resin composition instead of
Since no harmful gas is generated during combustion, incineration is possible. However, these halogen-free resin compositions are made of PVC.
However, there is a drawback that the flame retardancy is inferior to the above. For example, comparing the oxygen index (OI) which is an evaluation scale of the flame retardancy of the resin composition, the OI of PVC is 23 to 40, whereas the OI of PE and PP is inferior to about 17 to 19. You can see that there is.

Therefore, in order to impart flame retardancy to a halogen-free resin composition such as PE or PP, a water-containing inorganic compound such as Mg (OH) ₂ is usually added to these. However, the specific gravity of the water-containing inorganic compound is large, and in order to obtain the same flame retardancy as PVC, it is necessary to add 120 parts by weight or more of the water-containing inorganic compound. The specific gravity of the flame-retardant resin composition containing no is almost the same as that of PVC. For this reason, there has been a problem that the specific gravity of a plastic using water as a specific gravity liquid as described below cannot be separated. That is, in order to recycle the collected plastic or to remove PVC that generates dioxin during combustion, the plastic is put into uniformly flowing water, and separated according to the difference in specific gravity of the plastic. For example, as shown in FIG.
Since olefin-based plastics 1 such as PE and PE have a lower specific gravity than water (specific gravity of about 0.9), they float up on the water surface, and PVC2 having a specific gravity higher than water (specific gravity of about 1.3) sinks in water. Styrene plastic 3 (specific gravity about 1.1)
Follows a different sedimentation trajectory from PVC2 because the specific gravity is greater than water and less than PVC2,
At the bottom of the sorting tank, styrene plastic 3 and PVC2
There are two types of accumulation distributions. Therefore, by utilizing this property, it is possible to separate the above-mentioned three types of plastics. However, since the above-described halogen-free flame-retardant resin composition and PVC have the same specific gravity, There was a disadvantage that it was not possible to separate the.

[0005] In addition, when a water-containing inorganic compound or the like is added to enhance the flame retardancy, the specific gravity becomes large. However, there is a problem that the accuracy of the method is poor, and the variation in the withstand voltage characteristics may be large depending on the location.

The present invention has been made in view of the above circumstances, has the same level of flame retardancy as PVC, does not generate harmful gases during incineration, and can be separated from PVC with specific gravity. It is another object of the present invention to provide a resin composition that can be accurately formed into a tape or a film.

[0007]

The above object is achieved by adding a flame-retardant material having a maximum particle diameter of 50 μm or less to a polyolefin resin, and having a specific gravity of 1.14 or less, an oxygen index of 24 or more, and heavy metal. The problem can be solved by a halogen-free flame-retardant resin composition having a content of less than 0.1% by weight. As the flame retardant, a water-containing inorganic compound and silicone powder are preferable. Further, the flame-retardant resin molded product of the present invention is a film-like, sheet-like, non-halogen flame-retardant resin composition.
Alternatively, it is formed into a tape shape.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
Examples of the polyolefin resin used in the present invention include linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE). Such as polyethylene (PE)
And polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA), ethylene-butyl acrylate copolymer (EBA), ethylene-ethylene-propylene rubber (EPR), And olefin-based copolymers. An acid-modified polyolefin modified by reacting an unsaturated carboxylic acid such as maleic anhydride or acrylic acid or a derivative thereof during or after polymerization of these polyolefin resins can also be used. These resins may be used alone or in a combination of two or more. Particularly, ethylene-vinyl acetate copolymer (EVA) is preferably used in the present invention because it is a material that can easily improve the flame retardancy. When EVA is used, it is particularly preferable that the content of the comonomer (VA) used for copolymerization with ethylene is 15 to 40% by weight. If the content of the comonomer is less than this, the flame retardancy is inferior, and if it is more than this, the pellets stick together due to stickiness (adhesion) and the workability at the time of extrusion molding is unfavorable.

The flame retardant used in the present invention exhibits flame retardancy when burned when added to the above-mentioned polyolefin resin, and powder having a maximum particle diameter of 50 μm or less is used. Here, in the present invention, the expression that the maximum particle diameter is 50 μm or less means that 99.9% by weight or more of the particles contained in the range of 50 μm or less in the cumulative particle size distribution. Specifically, magnesium hydroxide (Mg (O
H) A powder obtained by adjusting the particle size of a water-containing inorganic compound such as ₂ ) or aluminum hydroxide so that the maximum particle size is 50 μm or less is preferably used. The amount of the water-containing inorganic compound to be added is in the range of 5 to 50 parts by weight, more preferably 35 to 45 parts by weight, based on 100 parts by weight of the polyolefin resin. If the amount of the water-containing inorganic compound is too small, favorable flame retardancy cannot be obtained. If the amount is too large, the specific gravity of the obtained halogen-free flame-retardant resin composition becomes too large, so that the specific gravity cannot be separated from PVC.

Further, other flame retardants other than the above-mentioned hydrous inorganic compounds may be used in combination. As the flame-retardant material to be used in combination, any of organic and inorganic materials may be used as long as the material contributes to the improvement of the flame-retardancy by adding a small amount when used in combination with the hydrous inorganic compound.
Those which do not contain heavy metals such as b are preferred. In order to suppress the specific gravity of the resin composition to 1.14 or less, a resin composition having a small density is preferable. For example, silicone powder whose particle size has been adjusted so that the maximum particle diameter is 50 μm or less can be suitably used. Silicone powder forms a shell-like heat-insulating layer by combustion and improves flame retardancy. Further, since the density is smaller than that of the above-mentioned hydrous inorganic compound, low specific gravity and high flame retardancy can be simultaneously achieved by reducing the amount of the hydrous inorganic compound added and adding silicone powder instead. When silicone powder is added as a flame retardant, the weather resistance of the resin can be improved. Conventionally, it is widely known to add carbon black to improve the weather resistance of a resin.However, when carbon black is added, the resin composition is colored black. Become. On the other hand, if you add silicone powder,
It is possible to improve the weather resistance and to obtain a resin composition having good coloring properties since the resin does not become dark. The specific gravity of the non-halogen flame-retardant resin composition is 1.1 depending on the amount of the water-containing inorganic compound added.
It is set so as not to exceed 4, preferably 3 to 55 parts by weight, more preferably 5 to 15 parts by weight based on 100 parts by weight of the polyolefin resin. If the addition amount of the silicone powder is too small, the effect of adding the flame retardancy cannot be obtained, and if the addition amount exceeds the above range, the improvement of the flame retardancy cannot be expected much because the raw material cost increases only.

It is preferable to further add an antioxidant. The anti-aging agent is not particularly limited, but for example, phenol-based and amine-based agents can be preferably used. If the amount of the antioxidant is too small, the effect of the addition cannot be obtained. If the amount is too large, blooming or bleed out may occur.
It is preferably from 0.1 part by weight to 2.0 parts by weight based on part by weight.

In addition to the above-mentioned compounding materials, ultraviolet absorbers, crosslinking agents, copper damage inhibitors, pigments, dyes and other coloring agents,
A small amount of inorganic fine powder such as talc and the like can be blended with appropriate additives depending on the application, but when these additives are solid, a powder having a maximum particle diameter of 50 μm or less is used. Is preferred. In addition, these additives do not contain halogen, especially lead (Pb), and cadmium (C
A substance which does not contain harmful heavy metals as much as possible such as d) is selected, and the content of harmful heavy metals in the non-halogen flame-retardant resin composition of the present invention is suppressed to less than 0.1% by weight.

The non-halogen flame-retardant resin composition of the present invention is prepared by adding a flame-retardant material having a maximum particle diameter of 50 μm or less to a polyolefin resin, and having a specific gravity of 1.14 or less and an oxygen index of 2 or less.
4 or more, and the heavy metal content is less than 0.1% by weight. The non-halogen flame-retardant resin composition of the present invention was formed into a thin film such as a film, a sheet, and a tape because the added flame retardant was as fine as 50 μm or less in maximum particle size and the particle size variation was small. Sometimes a molded article with excellent homogeneity is obtained. Specifically, the thickness variation is small, the mechanical properties such as tensile strength and elongation are good, and the withstand voltage does not greatly differ depending on the part. In particular, these effects are remarkable in a thin material having a thickness of 100 μm or less. Further, the non-halogen flame-retardant resin composition of the present invention has a self-extinguishing flame retardancy equivalent to that of PVC because the oxygen index is 24 or more, and it is difficult to burn in a fire,
Low smoke emission. Further, since it does not contain halogen, it does not generate toxic gases such as dioxin and halogen gas during combustion, so it can be incinerated and disposed of, and does not generate toxic gas even in the event of fire. Further, since the specific gravity is 1.14 or less, which is smaller than that of PVC, P is determined by specific gravity separation using running water as a specific gravity liquid.
It can be easily separated from VC. Therefore, it is possible to recycle by separating and collecting, heat recovery as fuel,
Alternatively, it can be reused as a material. Furthermore, since it contains almost no heavy metal, it is environmentally preferable, and landfill disposal is possible. The non-halogen flame-retardant resin composition of the present invention having such properties is particularly suitable for, for example, a flame-retardant film, a flame-retardant tape, a flame-retardant wallpaper, a flame-retardant leather and the like.

[0014]

EXAMPLES Hereinafter, the effects of the present invention will be clarified by showing specific examples. As examples and comparative examples of the present invention,
Various components were blended in the blending ratio (unit: parts by weight) shown in Table 1 below, and kneaded with a kneader to obtain a resin composition. As the base resin, ethylene-vinyl acetate content of 19% by weight was used.
A vinyl acetate copolymer (EVA) was used. Magnesium hydroxide (Mg (OH) ₂ ) and silicone powder were used in combination as the flame retardant. As the magnesium hydroxide, a powder having a maximum particle diameter of 20 μm or less (brand 1) within the scope of the present invention and a powder having a maximum particle diameter of 100 μm (brand 2) outside the scope of the present invention were prepared. Also, as the silicone powder, those having a maximum particle diameter of 10 μm within the scope of the present invention.
m (brand A), 20 μm (brand B) and 50 μm (brand C) were prepared, and those having a maximum particle diameter of 500 μm (brand D) were prepared as those outside the scope of the present invention. As an anti-aging material, Irganox 1010 manufactured by Ciba-Geigy was used.

Next, each of the resin compositions was extruded into a film with a thickness of 100 μm using a T-die. The prepared sample film (100 mm × 100
mm), the thickness, tensile strength and elongation according to JIS K7113, and withstand voltage according to ASTM D1000-93 were measured. For each resin composition, JI
The oxygen index (OI) according to SK7201 and the specific gravity were measured. The results are shown in Table 1 below. Note that none of the resin compositions contained heavy metals.

[0016]

[Table 1]

From the results shown in Table 1, it is found that Comparative Example 1 in which magnesium hydroxide having a maximum particle size of more than 50 μm was added and Comparative Example 2 in which silicone powder having a maximum particle size of more than 50 μm was added, had the thickness of the sample film produced. In some cases, the accuracy was poor, the withstand voltage characteristics varied greatly, and the withstand voltage was extremely low. Also, the tensile strength and elongation were inferior to those of Examples 1 to 3. In Comparative Example 3, the oxygen index was smaller than 24, and sufficient flame retardancy was not obtained. In Comparative Example 4, the specific gravity was larger than 1.14.

[0018]

As described above, the non-halogen flame-retardant resin composition of the present invention has the same flame retardancy as PVC.
Since it does not contain halogen, it can be incinerated and the flame retardant added has a very small particle size and a small variation in particle size, so it is homogeneous when formed into a film, sheet, tape, etc. A molded article having excellent properties can be obtained.
Moreover, since it contains almost no heavy metal, landfill disposal is possible, which is environmentally preferable. Furthermore, since the specific gravity is 1.14 or less, it is possible to separate and collect from PVC by specific gravity separation. In addition, when a water-containing inorganic compound and silicone powder are used as a flame retardant auxiliary, a halogen-free flame-retardant resin composition having the above-mentioned properties can be preferably realized. The nature is also obtained. Then, the non-halogen flame-retardant resin composition of the present invention is in the form of a film, a sheet,
Molded articles molded into thin shapes such as tapes have excellent homogeneity, good thickness accuracy, and high resistance because the flame retardant added to the resin composition is minute and the particle size variation is small. Variations in voltage characteristics are small, and mechanical characteristics are also good.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a sedimentation trajectory of plastic in a water flow.

[Explanation of symbols]

1: olefin plastic, 2: polyvinyl chloride,
3: Styrene-based plastic

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4J002 BB031 BB061 BB071 BB121 BB151 BB211 BF031 BG041 CP032 DE076 DE146 FA082 FA086 FD132 FD136 5G305 AA14 AB15 AB25 AB27 AB28 AB35 BA12 BA13 BA15 BA18 CA20 CA03 CA04 CD13

Claims (3)

[Claims] 1. A polyolefin resin to which a flame retardant having a maximum particle diameter of 50 μm or less is added, and a specific gravity of 1.14 is obtained.
Hereinafter, the oxygen index is 24 or more, and the content of heavy metal is 0.1
A halogen-free flame-retardant resin composition having a content of less than 10% by weight. 2. The halogen-free flame-retardant resin composition according to claim 1, wherein the flame-retardant material comprises a water-containing inorganic compound and silicone powder. 3. The non-halogen flame-retardant resin composition according to claim 1 or 2,
Or a flame-retardant resin molded product formed into a tape shape.