KR101273791B1 - A pelleted composition with flame resistance and a method of thereof - Google Patents

Abstract

The present invention contains 1 to 80.0 wt% of phosphinic acid salt and diphosphinic acid salt or polymer thereof, 10 to 80.0 wt% of nitrogen-containing synergist or phosphorus / nitrogen flame retardant, and 0.1 to 30 wt% of piperazine compound flame retardant. Flame retardant formulations containing 100% by weight of each component by heating due to self latent heat or a device equipped with a condition that the content of volatile substances including water in the flame retardant formulation is 1 wt% or less and heated at a temperature of 25 to 300 ° C. A method of making and a thermoplastic resin composition containing said flame retardant formulation blend.

Description

A pelleted composition with flame resistance and a method of

The present invention relates to a flame retardant blend and a method for producing the same, and more particularly, to a pellet-type flame retardant composition and a method for producing the same.

The traditional flame retardant market mainly consists of halogen-based bromine compounds, but halogenated dioxins generated during fire or incineration are not only fatal to humans but also cause environmental pollution. Therefore, in the United States and Europe, the use of halogen-based flame retardants is legally restricted, and according to this trend, the development of flame-retardant technology using non-halogen-based flame retardants is currently in progress worldwide. Compared to the above, there are various problems such as relatively high price, high prescription amount and deterioration of resin properties.

Thermoplastic resins have excellent chemical resistance, mechanical strength, electrical insulation, and the like, and are widely used in housings, connectors, and the like of electrical and electronic parts. In the case of using such a thermoplastic resin in the field of electric and electronic devices, it is essential to impart flame retardancy in order to secure safety against fire.

The use of flame retardants affects the stability of thermoplastics during processing in the molten state. Flame retardants must be used in large amounts to satisfy the appropriate flame retardancy of plastics according to international standards. Due to the chemical reactivity that requires flame retardancy at high temperatures, flame retardants can impair the processing stability of plastics. For example, polymer degradation, crosslinking reactions, gas release or decolorization can be increased. In addition, when using such a method, there is a problem that halogen-based gas is generated by pyrolysis during processing, resulting in deterioration of the work environment due to toxic gases and corrosion of equipment such as molding machines and molds.

In particular, the use of phosphorus flame retardants in polyamides and polyesters has been found to be insufficient to suppress phenomena that occur during processing such as discoloration and resin degradation.

The use of flame retardants consisting of phosphinates combined with melamine polyphosphate results in partial polymer degradation and smoke generation during extrusion and injection molding, in particular discoloration of the polymer at processing temperatures above 300 ° C. In addition, when a very low dispersibility flame retardant is prescribed, even secondary processing is required, which results in aggravating the above problem in terms of processability. Therefore, in order to solve such processability, dispersibility and deterioration of finished product properties, processor companies make various efforts.

European Patent Publication No. 699708 describes calcium phosphate and aluminum phosphinate as effective flame retardant components for polyesters, which can suppress deterioration of material properties of polymer molding materials compared to the use of alkali metal salts. It is described as. In addition, for various polymers, in international patent applications PCT / EP97 / 01664, German Patent Publication No. 19734437 and German Patent Publication No. 19737727 for synergistic combinations of phosphinates with any kind of nitrogen-containing compounds. These are described as being able to improve flame retardancy compared with the case of using phosphinate alone. For example, one of the synergists includes melamine and melamine compounds (melamine cyanurate and melamine phosphate), which alone can impart some degree of flame retardancy to any kind of thermoplastic, It is reported that the combination with acid salts can have a more significant effect.

In recent years, the piperazine pyrophosphate compound has attracted attention as having an excellent effect as one component of a flame retardant composition added to a synthetic resin. There have been many reports on the method for producing such pyrophosphate pyrophosphate. For example, Japanese Patent Application Laid-Open No. 47-88791 discloses a method in which piperazine hydrochloride and sodium pyrophosphate are reacted in an aqueous solution to obtain piperazine pyrophosphate as poorly water-soluble precipitation. U.S. Pat.Nos.3810850 and 4599375 disclose hydrochloric acid treatment by reacting piperazine (anhydrous) and sodium pyrophosphate (anhydride) in an aqueous solution to obtain piperazine pyrophosphate as precipitation.

The well-known chemical formula of piperazine pyrophosphate is as follows.

Pyrophosphate Pyrophosphate

However, it is well known that sodium chloride or piperazine sodium salts are produced as byproducts produced by the above method, which are likely to adversely affect the application to semiconductors and electronic devices. Moreover, in these methods, the problem is that the yield is poor, the raw materials are expensive, and the waste is expensive.

In particular, when piperazine pyrophosphate is used as one component of the flame retardant composition, the effect of impurities may also be a problem, but in order to exhibit v-0 grade flame retardancy, a large amount of at least about 20 wt% has to be prescribed. This is due to the high use of expensive pyrophosphate pyrophosphate, which is not very cost effective.

In addition, for example, when a flame retardant blend containing volatile substances such as moisture, ammonia and gaseous melamine is used in polyester [polyethylene terephthalate (PET) or polybutylene terephthalate (PBT)], polyamide and polyolefin resin. , Will have undesirable characteristic effects. This undesirable effect may form bubbles during extrusion or deposits on the mold during injection molding.

The present invention is to solve the problems of the prior art as described above, using a phosphinate or diphosphinate compound, piperazine-based compound, melamine-based compound in an appropriate ratio in the thermoplastic base resin and optionally a filler therein It is an object of the present invention to provide a thermoplastic resin composition which is excellent in flame retardancy and does not deteriorate in mechanical properties and does not contain halogen, and thus does not generate halogenated harmful gas, and a method for producing the same.

The present invention, in order to achieve the object of the present invention as described above, 1 to 80.0 wt% of phosphinic acid salt and diphosphinic acid salt or polymer thereof, 10 to 80.0 wt% of melamine polyphosphate which is a phosphorus / nitrogen flame retardant and pipette diphosphate As a product stabilizer containing 0.1 wt% to 30.0 wt% of condensation product, the amount of generated water including 0.1 to 30 wt% of basic or amphoteric or inorganic mixture thereof is 1 wt% or less, and the sum of each component is 100 wt%. A flame retardant composition is provided.

According to the present invention, it is possible to provide a pelletized flame retardant resin composition having increased flame retardancy, improved processability of a polymer, excellent resin applicability, and excellent processing characteristics and coloring characteristics.

1 is a graph showing the results of thermal analysis using a flame retardant formulation.

The blend of the present invention reduces the discoloration of the plastic in the process of processing in the molten state, suppresses the decomposition of the plastic and at the same time maintains flame retardancy completely. It has also been surprisingly found that the additives of the present invention completely eliminate volatile foreign matter generation during extrusion and injection molding. The metals included in the well known phosphinate or diphosphinate compounds are preferably calcium, aluminum or zinc. Suitable phosphinic acid salts are described in the cited PCT / W097 / 39053. The flame retardancy of phosphinic salts is known to be improved by combining with additional flame retardants, preferably nitrogen synergists or phosphorus / nitrogen flame retardants, but the results of the piperazine compounds are unknown.

When phosphoric acid and piperazine are reacted in an aqueous solution, hydrochloric acid treatment and recrystallization, diphosphate piperazine can be obtained as an intermediate of piperazine pyrophosphate. In addition, a poorly water-soluble pyrophosphate can be obtained by performing a dehydration condensation reaction. Both materials have excellent properties as flame retardants, but piperazine diphosphate dissolves well in water and has limitations in use. Equation 2 below shows the production of piperazine pyrophosphate as a intermediate and the dehydration condensation of piperazine diphosphate.

Piperazine Diphosphate Piperazine pyrophosphate

The resin composition excellent in flame retardancy according to the present invention comprises 1 to 80.0 parts by weight of a phosphinate or diphosphinate compound in 100 parts by weight of a thermoplastic base resin; 0.1-30 parts by weight of piperazine compound; Melamine-based compound may include 10 to 80 parts by weight and a filler. The piperazine compound may be piperazine pyrophosphate, but diphosphate piperazine also plays a very good role. In particular, it is preferable to use a mixer that can adequately provide heat when producing a uniform and good dispersibility mixture of a suitable ratio, the dehydration condensation reaction proceeds due to the heat and latent heat applied to the diphosphate piperazine Is transformed into piperazine pyrophosphate. When the dehydration condensation reaction is completed, a very good quality flame retardant formulation can be achieved. However, if the degree of dehydration is small, the water content is somewhat reduced. Sufficient mixing and moisture control are important in mixers that can provide heat as they can affect heat.

In addition, the above volatile components may point to gaseous melamine and ammonia, including water, and the presence of these volatile impurities indicates that the compounded flame retardant may be uneven and whitening and browning of the resin surface during extrusion and injection with a thermoplastic resin. It causes a serious phenomenon such as. In order to prevent this phenomenon, it is necessary to have a process such as pre-blending, and to have such intermediate mixing process and partial chemical reaction process, and to solve mechanical and physical process for uniform dispersion and concise process. It was a step. In particular, it can not be pointed out as any one component, but the content of volatile components of the pellets formulated by applying heat or latent heat should be maintained at about 1wt% or less to serve as a good flame retardant.

If a very low dispersibility flame retardant is prescribed, it may induce processability, dispersibility and degradation of finished product properties. In some cases, product properties may be secured through secondary processing. In some cases, the cost increase in the master batch process and the modification of processing equipment other than flame retardants can be corrected. There is a solution through injection of non-halogen flame retardants that are difficult to disperse in the middle of the extruder, that is, side-feeding. It is inconvenient to correct.

The processability, dispersibility and degradation of finished product properties can be improved by pre-blending the flame retardant formulation. Non-halogen flame retardant systems usually achieve synergy by using a specific proportion of flame retardants with different flame retardant mechanisms, and there may be a variety of flame retardant formulations, such that each company typically has its own flame retardant formulation. Focusing on this, if the processing is provided in the form of granules, pellets, etc. according to the flame retardant formulations that each company has, the problem of dispersion is solved from the user's point of view, and the problem of scattering of powder type flame retardant can be naturally solved. In addition, it is much cheaper to solve additional costs such as masterbatch and side-feeding.

As the flame retardant formulation of the present invention, in particular, a mixed formulation of phosphinate, piperazine compound and melamine has been found to be very advantageous for the application by formulating into pellets through the primary processing. The pellets can be formulated only by mixing, and can be formulated using a certain amount of organic and inorganic binders as necessary. The flame retardant formulation is therefore preferably present as granules, flakes, powders and / or micromaterials, more preferably in the form of a masterbatch blended as a physical mixture of solids, melt mixtures, compressed materials, extrudates or resins. Exist as.

The flame retardant blend pellets according to the invention are partially melted in a melt mixer, for example a brabender mixer or a single or twin screw extruder or kneader, using conventional methods, for example after mixing all or part of the components in a dry state in the mixer. Physically mixed pellet formulations can be prepared by or by heat. Examples of heating zones include extruders such as single and twin screw extruders; Autoclave; Turbo mixer; Plow blade mixers; Tumble mixers; Turbulence mixers; Ribbon blade mixer; Mixed extruder; Continuous and discontinuous kneading machines; There are heating zones of the kind found in rotary drum ovens and pellet presses (Kahl-Germany). The various components of the flame retardant formulations of the invention can also be injected together at the inlet of the extruder. They may also be injected at other locations in the extruder. Several components can be added to the polymer, such as colorants, stabilizers, flame retardant compositions, compounds having a synergistic effect with the flame retardant composition and / or other flame retardant components. The formulations according to the invention can be processed into semi-finished or final products using methods known to those skilled in the art, such as injection molding.

In the phosphinate or diphosphinate compounds used in the flame retardant formulations of the invention, the metal is preferably aluminum, calcium, magnesium, zinc or the like. The phosphorus / nitrogen flame retardant is also a dimelamine phosphate, dimelamine pyrophosphate, melamine phosphate, melamine pyrophosphate, melamine polyphosphate, melam polyphosphate, melon polyphosphate and melem polyphosphate mixed polysalts. More preferably, it is melamine polyphosphate.

It is also well known that various metal oxides can be used as fillers and stabilizers. Particularly preferably magnesium oxide, zinc oxide, manganese oxide and / or tin oxide, the hydroxide is preferably magnesium hydroxide, hydrotalcite, hydrocalcite, calcium hydroxide, zinc hydroxide, tin oxide hydrate and / or manganese hydroxide to be.

The component ratios of the flame retardant formulations depend in fact on the intended application and can vary over a wide range. The flame retardant formulation consists of 1 to 80.0 wt% of pyrophosphate salt, 0.1 to 30 wt% of diphosphate diphosphate and 10 to 80 wt% of melamine polyphosphate, depending on the field of application serving as the first component. 1 shows the results of thermal analysis using a flame retardant formulation. Judging from the thermal decomposition around 320 degrees, it can be seen that it has a very good characteristics.

Particular preference is given to using the flame retardant blend in the plastic molding composition in an amount of from 2 to 50% by weight, based on the plastic molding composition. Plastics are preferably impact resistant polystyrenes, polyphenylene ethers, polyamides, polyesters, polycarbonates, and ABS (acrylonitrile-butadiene-styrene) or PC / ABS (polycarbonate / acrylonitrile-butadiene-styrene) Or thermoplastic polymers of blends or polymer blends of PPE / HIPS (polyphenylene ether / HI polystyrene) type plastics. More preferred are polyamides, polyesters and PPE / HIPS blends.

As another thermoplastic, polyolefin, high density polyethylene, low density polyethylene, linear low density polyethylene, α-olefin polymer such as polybutene-1, poly-3-methylpentene or ethylene-vinyl acetate copolymer, ethylene-propylene Polyolefins such as copolymers and copolymers thereof, polyvinyl chloride, polyvinylidene chloride, chlorinated polyethylene, chlorinated polypropylene, polyvinylidene fluoride, rubber, vinyl chloride-vinyl acetate copolymer, vinyl chloride-ethylene copolymer, Vinyl chloride-vinylidene chloride copolymer, vinyl chloride-vinylidene chloride-vinyl acetate terpolymer, vinyl chloride-acrylic acid ester copolymer, vinyl chloride-maleic acid ester copolymer, vinyl chloride-cyclohexylmaleimide copolymer (vinyl chloride -halogenated resins such as cyclohexyl maleimide copolymers, petroleum resins, coumarone resins, polystyrene , Copolymers of polyvinyl acetate, acrylic resins, styrene and / or α-methylstyrene with other monomers (e.g. maleic anhydride, phenylmaleimide, methyl methacrylate, butadiene, acrylonitrile, etc.) For example, AS resin, ABS resin, MBS resin, heat resistant ABS resin), polymethylmethacryl), polyvinyl alcohol, polyvinyl formal, polyvinyl butyral, polyethylene terephthal), (polyethylene terephthalate) ) And polyamides such as polybutylene terephthal), polyamides such as polyphenylene octabutadi, polycaprolactam and polyhexamethylene adipamide, polycarbonates and polycarbonates Thermoplastic resins such as / ABS resins, branched polycarbonates, polyacetals, polyphenylenesulfadides, polyurethanes, and fibrin resins, and in particular, polypropylene resins. It is preferred.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. The following examples are intended to assist those skilled in the art, but are not intended to limit the invention.

[Components Used]

Polybutylene Terephthalate (PBT): Commercial Standard Polymer (Granules)

Polypropylene (PP): commercially available standard polymer (granule)

Flame Retardant Ingredients (Powder)

Aluminum salt of diethylphosphinic acid (AP): OP (Client)

Melamine polyphosphate (MPP): NONPLA-601 (Doubon)

Hydrotalcite: PolyLizer-120 (Doobon)

Piperazine Diphosphate: The product synthesized here

[Pelletizing Test Flame Retardant Components and Preparation of Flame Retardant Plastic Molding Compositions]

Aluminum phosphinate, diphosphate diazine, melamine polyphosphate and inorganic metal hydroxide flame retardant components are mixed with lubricants and stabilizers in the appropriate proportions described, and twin screw extruder (or pellet press (Kahl group)) at a temperature of 100 to 300 ° C. In this case, the homogenized formulation was pelleted after incorporation into a temperature of about 25 to 200 without heating.

After sufficiently drying the pellet blend, the PBT resin was processed as a molding composition to prepare a test specimen at a temperature of 150 to 300 ° C. (PBT) using a brabender and a press, referring to UL 94 test (Underwriter Laboratories). Test and classify flame retardancy. Tests in all cases were performed under the same conditions for the purpose of uniform mixing.

Example 1

Simultaneously combine the flame retardant formulation with 61 wt% of aluminum phosphinate, 3 wt% of diphosphate diphosphate, 30 wt% of melamine polyphosphate, and 6 wt% of magnesium hydroxide compound (the sum of the components being 100% by weight) as inorganic metal hydroxide. It was injected into a corotating twin screw extruder (Werder & Pfleiderer, type ZSK 30/33). The cylinder temperature was set to 120 degreeC, the screw speed 35 rpm and the residence time was 2 minutes. The content of moisture in the volatiles of the formulated pellets measured with a moisture meter is 1.5 wt%.

Example 2

Except that the cylinder temperature was set to 200 ℃ was carried out under the same conditions as in Example 1, the moisture content of the formulated pellets measured by a moisture meter is 0.67wt%.

Example 3

Except that the cylinder temperature was set to 200 ℃, the speed was slowed to 5 minutes, the residence time was carried out under the same conditions as in Example 1, the content of the measured pellets measured by a moisture meter is 0.4wt%. .

Example 4

The same formulation as in Example 1 was used at about 90 degrees using pellet press-kal (Kahl), and the formulated pellets had a water content of 0.88 wt% as measured by a moisture meter.

Example 5

Flame retardant formulations comprising 10 wt% of aluminum phosphinic acid salt, 5 wt% of melamine polyphosphate and 1 wt% of magnesium hydroxide compound as inorganic metal hydroxide were prepared using PBT or PP using the formulated pellet prepared from the flame retardant formulation prepared in Example 4. Test specimens were prepared at a temperature of 150 to 300 ° C. using a brabender and a press, and applied to each (approximately 100 wt% of the resin containing components) and tested for flame retardancy with reference to UL 94 test (Underwriter Laboratories). It was.

Example 6

Flame-retardant experiments were carried out in the same manner as in the pellet-type flame retardant formulation prepared in Example 5 containing piperazine diphosphate 0.5wt%.

Example 7

The aluminum phosphinic acid salt was the same as Example 6 except for the flame retardant formulation containing 0.5 wt%, piperazine diphosphate 3 wt%, melamine polyphosphate 10 wt%, and 1 wt% magnesium hydroxide compound as the inorganic metal hydroxide.

Example 8

The aluminum phosphinic acid salt was the same as Example 6 except for the flame retardant formulation containing 0.5 wt%, piperazine diphosphate 10 wt%, melamine polyphosphate 5 wt%, and 1 wt% magnesium hydroxide compound as the inorganic metal hydroxide.

The pellets prepared in Examples 1, 2, 3, and 4 above were applied to PBT or PP, respectively, to prepare test specimens at temperatures of 150 to 300 ° C. using a brabender and a press, see UL 94 test. The flame retardancy was tested and the results are shown in Table 1.

The results of the tests in which the flame retardant compositions according to the invention are used are listed in Tables 1 and 2. All amounts are quoted as weight percent and are based on plastic molding compositions that include a flame retardant formulation additive.

It is proved from this example that the piperazine-based phosphorus additive according to the present invention sufficiently improves the processability of the polymer while slightly increasing the flame retardancy. In addition, incorporation of aluminum phosphinic acid salts, melamine polyphosphate, diphosphate diazine and hydrotalcite as a flame retardant in polyester (PBT) shows UL-94 grade, which can be classified as V-0, but it is light brown. Polymer degradation is shown. This phenomenon is judged to be a phenomenon in which a large amount of water contained after formulating the pellet of the compound flame retardant (Table 1).

The change according to the presence or absence of piperazine diphosphate as a flame retardant in polyester (PBT) can be compared through Examples 5 and 6. Although V-0 grade is shown as UL-94 grade, the digestion time and color stability of 10 data summed with 5 samples are better when diphosphate is added. In addition, in the case of Examples 6, 7, and 8, which is a flame retardant formulation prescribed with diphosphate, the result was good when applied to PP as an olefin resin as well as PBT as a functional resin. It can be said that it is compared with the case where there is a problem in resin applicability.

Example Water content after pellet formulation (%) ⁽¹⁾ Digestion Time (sec) ⁽²⁾ UL 94 classification color One 1.50 19.9 V-0 Light brown 2 0.67 9.3 V-0 White 3 0.40 8.6 V-0 White 4 0.88 13.4 V-0 White

⁽¹⁾ Moisture meter: Use METTLER TOREDO HG53

⁽²⁾ Total digestion time summed after measuring five samples each

Example Suzy AP MPP DPP HT Digestion time (seconds) UL 94 classification color 5

6
7

8 PBT
PP
PBT
PP
PBT
PP 10 5 0 1
10 5 0 1
10 5 0.5 1
0.5 10 3 1
0.5 10 3 1
0.5 5 10 1 21
-
15
10
19
8 V-0
-
V-0
V-0
V-0
V-0 Light brown
-
White
White
White
White

AP: diethylphosphate aluminum, MPP: melamine polyphosphate, DPP: diphosphate piperazine

HT: Hydrotalcite

Claims (8)

1 to 80% by weight of phosphinate;
0.5-30% by weight of piperazine diphosphate and
A pellet-type flame retardant formulation comprising a condensation formulation blended with melamine phosphate 10-80% by weight. The method of claim 1,
A pelletized flame retardant formulation further comprising 1% by weight or less of a volatile substance comprising water. The method of claim 1,
The pelletized flame retardant formulation is a pellet press. A pelletized flame retardant formulation obtained by heating at 25 to 300 ° C. in an autoclave or extruder. A flame retardant masterbatch prepared by mixing the pelletized flame retardant blend of claim 3 and a thermoplastic resin. A flame retardant plastic molding composition comprising the pelletized flame retardant blend of claim 1. 6. The method of claim 5,
Flame-retardant plastic molding composition, characterized in that the content of the pelletized flame retardant formulation is 10 to 50% by weight. delete 1 to 80% by weight of phosphinate;
0.5-30% by weight of piperazine diphosphate and
A method for producing a pelletized flame retardant compound, characterized in that the condensation compound containing 10 to 80% by weight of melamine phosphate is heated at 25 to 300 ° C. in a pellet press, autoclave or extruder.

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