KR20050122739A - Flame retardant waste pastic resin composition - Google Patents

Abstract

Flame retardant waste plastic resin composition of the present invention is 60-90% by weight of waste plastic; And it is made of shell powder 10-40% by weight, the shell powder is characterized in that the surface-modified by n-cetyltrimethylammonium bromide (CTAB) or polyimine salt (polyimine salt).

Description

Flame Retardant Waste Pastic Resin Composition

Field of invention

The present invention relates to a flame retardant waste plastic resin composition. More specifically, the present invention is composed of waste plastic and shell powder, and improve the environment by using waste resources, not only excellent mechanical strength and flame retardancy at the same time, there is no generation of toxic gas and flame retardancy that can reduce the cost It relates to a waste plastic resin composition.

Background of the Invention

In general, plastic materials are widely used because of their excellent workability, impact resistance, and functionality. These plastic materials are supplied in large quantities at low prices and are currently being used excessively. Accordingly, a large amount of waste plastics are generated, and thus, resources for recycling waste plastics are needed in order to protect the environment and recycle resources.

On the other hand, the plastic material itself is not fire resistant and has a limited use in some applications because of its easy burning properties. Therefore, if functionalities such as flame retardancy can be added, various benefits can be provided to the society, such as increased sales due to new demand creation, protection of plastic contents, fire prevention, awareness of packaging products, and promotion of development of functional grant technology. Will be.

To add functionality such as flame retardancy, it is common to add a flame retardant. The method of imparting flame retardancy is a method of suppressing combustion by consuming heat energy that must be maintained in the combustion process by an additive (cooling method), or a method of forming a protective film by condensing into a solid or gas to prevent the combustible material from contacting the gas ( Phosphorus compound), aluminum hydroxide or aluminum trioxide is added to produce a non-flammable heavy gas during combustion, thereby suppressing the reaction of the gases that proceed with combustion (dilution method) and halogen-based compounds to the combustion reaction The method of suppressing continuous reaction by absorbing H and OH radicals added by a flame retardant, etc. has been used.

However, the method of adding a halogen compound is suppressed due to the possibility of generating dioxin during incineration, and when using other flame retardants, there is a problem of lowering the physical properties of the resin itself or increasing the material cost due to the addition of the flame retardant.

On the other hand, Korea is one of the world's leading producers of oysters, with 475 oyster farms nationwide, reaching 3,600 ha by area. Therefore, the incidence of shells (oysters and shells) is inevitably increasing. Among them, recycling (harvesting, fertilizer) is only about 100,000 tons, and the remaining 150,000 tons are discarded because they are not treated (coastal, landfill, etc.), which causes many environmental problems. Considering this reality, there is an urgent need to develop technologies for the efficient use of shells in terms of the use of effective resources and the resolution of environmental problems.

Therefore, in order to solve the above problems, the present inventors use waste materials, which are discarded waste resources, as flame retardants of waste plastic resins to improve the environment by utilizing waste resources, and at the same time excellent in mechanical strength and flame retardancy, and also toxic. It is to develop a flame-retardant waste plastic resin composition that can reduce the cost without the generation of gas.

An object of the present invention is to provide a flame retardant waste plastic resin composition excellent in flame retardancy.

Another object of the present invention is to provide a flame-retardant waste plastic resin composition without the generation of toxic gases such as dioxins.

Still another object of the present invention is to provide a flame retardant waste plastic resin composition which can reduce environmental pollution by developing new recycling technology of plastic waste and shell powder which are considered as the main causes of environmental pollution.

Still another object of the present invention is to provide a flame retardant waste plastic resin composition which can reduce manufacturing costs.

The above and other objects of the present invention can be achieved by the present invention described below.

Summary of the Invention

Flame retardant waste plastic resin composition of the present invention is 60-90% by weight of waste plastic; And it is made of shell powder 10-40% by weight, the shell powder is characterized in that the surface-modified by n-cetyltrimethylammonium bromide or polyimine salt (polyimine salt). Hereinafter, the content of the present invention will be described in detail below.

Detailed Description of the Invention

(1) waste plastic

As the base resin that can be used in the present invention, waste plastic is used. Plastic materials have been limited in some applications due to their flammability, which is a fatal drawback despite their excellent properties, ie processability, impact resistance, functionality, and the like. In addition, the use of plastic materials in a large amount is increasing the generation of plastics, and in order to protect the environment and recycling resources, the recycling technology of waste plastics is required, but the recycling rate of waste plastics is not high problem is a problem.

In the present invention, by using the shell powder as a flame retardant in the discarded waste plastics, not only improves the flame retardancy of the waste plastic resin itself, but also develops a new recycling technology of plastic waste, and has developed a resin composition that can reduce environmental pollution. will be.

In the present invention, the waste plastic resin is used in 60-90% by weight of the total resin composition.

(2) shell powder

The shell used in the present invention is a waste resource generated in large quantities in the oyster farm, so when used as a flame retardant can not only develop a new flame retardant, but also have a significant effect in terms of the use of effective resources and the elimination of environmental problems.

Elemental analysis of shell powder showed that 26.79% oxygen, 9.991% carbon, 0.599% hydrogen, 0.589% sulfur, and 0.180% nitrogen were used. Weight loss was observed, indicating that the main component of the shell was calcium carbonate. On the other hand, as a result of reacting the shell with 0.1 M hydrochloric acid, a large amount of carbon dioxide was immediately generated, and the main component of the shell was calcium carbonate.

As such, the shell powder is calcium carbonate (CaCO ₃ ) as the main component, such calcium carbonate decomposes itself at high temperature (about 750 ° C.) to dehydrated lime (CaO) and carbon dioxide (CO ₂ ). It is to have a function to suppress combustion. In addition, the present invention is superior to other methods in that it uses the shell, a waste resource.

1 is a model showing the principle that the waste plastic resin composition according to the present invention has flame retardancy. That is, calcium carbonate, which is a major component of the shell, decomposes itself at about 750-800 ° C. to emit carbon dioxide, and the carbon dioxide blocks the oxygen supply to suppress combustion.

The shell powder is used by washing and drying the shell powder in order to increase the performance of the shell. Specifically, the shell is washed in natural state, dried, and further washed again, and dried at high temperature at about 700 ℃ to remove salts, algae, microorganisms and the like. It can then be sterilized by conventional methods and then finely divided to 2-5 탆. Purification of shell powder is repeated several times of washing and drying to completely remove residual salts and odors and to keep the pH of the washed solution neutral.

In particular, when the surface of the shell is modified with a surfactant or the like, odor molecules such as hydrogen sulfide, ammonia, melcaptans, and amines, VOC, and the like are adsorbed on the shell surface, thereby having a function of inhibiting the emission of volatile molecules. As the surfactant that can be used in the present invention, n-cetyltrimethylammonium bromide (CTAB) or polyimine salt is preferable.

However, when the shell powder is added in an excessive amount, it is important to add it in an appropriate content because the physical properties of the resin itself are lowered.

In the present invention, the shell powder is preferably contained in 10-40% by weight of the total resin composition. When the shell powder exceeds 40% by weight, the flame retardancy is excellent, but mechanical properties such as elongation at break and impact strength are lowered, and when it contains less than 10% by weight, the flame retardant fragrance effect is insignificant.

In the present invention, additives such as flame retardants, impact modifiers, inorganic additives, heat stabilizers, antioxidants, pigments and / or dyes may be added in a conventional manner as necessary.

The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

Examples 1 to 5: Physical property test according to shell addition rate

Example 1

10% by weight of shell powder for fertilizers (purchased from Haesung) and 90% by weight of waste plastics (purchased from the resource recycling work) having a size of 20 μm was pelletized using a twin screw extruder at 220 ° C. To prepare a master batch (M / B). The prepared master batch was injected to prepare a physical specimen, and the mechanical strength and the flame retardance according to the UL 94 VB flame retardant standard were measured for the prepared specimen.

Example 2

The same procedure as in Example 1 was carried out except that 20 wt% shell powder and 80 wt% waste plastic were used.

Example 3

The same procedure as in Example 1 was carried out except that 30 wt% shell powder and 70 wt% waste plastic were used.

Example 4

The same procedure as in Example 1 was carried out except that 40 wt% shell powder and 60 wt% waste plastic were used.

Example 5

Purified shell powder was added to 1 liter of 50 mM CTAB (n-cetyltrimethylammonium bromide) aqueous solution, and the mixture was slowly stirred for 3 days to replace the surfactant on the surface. This was carried out in the same manner as in Example 1 except that the shell powder was recovered by filtration and then dried at 150 ° C. to use the modified shell powder.

Comparative Example 1

Except for using the shell powder 100% by weight of pure LDPE was carried out in the same manner as in Example 1.

Comparative Example 2

Except for using the shell powder 100% by weight of waste plastics were carried out in the same manner as in Example 1.

Comparative Example 3

Except for using 50% by weight of shell powder and 50% by weight of waste plastic was carried out in the same manner as in Example 1.

Flame retardant evaluation of the film prepared from Example 1-5 and Comparative Example 1-3 is shown in Table 1. The flame retardant assessment is based on the time from ignition to fire (T ₁ ), the time from fire to fire (T ₂ ), and the time from fire after 25 mm (T ₃ ), respectively. Measured.

Flame Retardant Rating T ₁ T ₂ T ₃ Example One 12 " 2'41 " 0" 2 15 " 2'41 " 0" 3 0" 0" 0" 4 0" 0" 0" 5 0" 0" 0" Comparative example One 10 " 7'42 " 4'43 " 2 12 " 6'13 " 3'28 " 3 0" 0" 0"

As shown in Table 1, it was found that the overall flame retardancy improved as the shell content increased. It was also confirmed that the shell was not burned at 30 wt% or more. However, it burned completely in Comparative Example 1-2 using pure LDPE or pure waste plastic. 2 is a photograph showing the combustion test results of the specimen prepared in Example. In FIG. 2, a and b show the flame retardant specimens of Comparative Examples 1 and 2, respectively, and c to f show the flame retardant specimens of Examples 1-4, respectively.

Tensile Strength (MPa) Elongation at Break (%) Impact Strength (J / M) Flexural Strength (MPa) Compressive strength (MPa) Heat Deflection Temperature (℃) Example One 16.2 114.2 465 0.6 28.5 100.1 2 15.9 87.2 453 0.7 35.5 105.2 3 17.2 64.3 327 0.8 40.4 107.4 4 17.1 37.9 212 1.1 42.5 112.4 5 17.3 121.4 473 0.8 32.3 103.8 Comparative example One 17.5 73.1 392 0.5 18.5 88.0 2 17.5 175.1 438 0.6 18.8 96.8 3 16.3 22.4 184 1.2 42.3 112.9

In Table 2, as a result of measuring the mechanical properties using the shell plastic waste containing the shell, the tensile strength showed a constant value without significant change in the shell content, the elongation at break was found to decrease at more than 10% by weight shell. Impact strength was observed to decrease at more than 20% by weight shell. On the other hand, it can be seen that the flexural strength, compressive strength, and heat deflection temperature improved with increasing shell content.

Examples 6 to 7: Physical property test according to shell size

Example 6

Except for using a fertilizer shell having a size of 20-30 ㎛ was carried out in the same manner as in Example 2, was carried out a total of six times to calculate the average value.

Example 7

Except for using a shell having a size of 2-3 ㎛ was carried out in the same manner as in Example 2, was carried out a total of six times to calculate the average value.

Physical property evaluation and flame retardant evaluation results for the film prepared in Example 6-7 are shown in Tables 3 and 4, respectively.

Stress (MPa) Elongation at Break (%) Impact Strength (J / M) Flexural Strength (MPa) Example 6 a 17.23 75.71 429.407 0.6430 b 15.32 88.00 445.857 0.5762 c 14.72 72.13 447.277 0.6101 d 15.18 94.05 472.326 0.6418 e 16.04 98.38 439.945 0.6454 f 17.28 94.93 486.503 0.5808 Average 15.96 87.20 453.552 0.6097 Example 7 a 18.27 58.25 580.581 0.6913 b 18.89 70.42 529.030 0.6510 c 17.45 83.87 658.715 0.6452 d 20.14 83.30 543.256 0.6263 e 16.49 105.20 612.689 0.6354 f 16.85 117.70 423.916 0.3649 Average 18.02 86.46 558.030 0.6000

T ₁ T ₂ T ₃ Example 6 15 " 2'41 " 0" Example 7 0" 0" 0"

As shown in Tables 3 and 4, the smaller the particle size of the shell was, the better the mechanical properties and the flame retardancy were confirmed.

Comparative Examples 4-9

It was carried out in the same manner as in Example 2, except that 20 wt% of a flame retardant roll, which is commonly used instead of shell, was used as the flame retardant. The eggs are shown in Table 5.

Flame retardant T ₁ T ₂ T ₃ Example 6 Shell 15 " 2 '41 " 0" Comparative Example 4 Antimony trioxide 0" 0" 0" 5 MgOH ₂ 10 " 5 '19 " 4 '36 " 6 Sodium borate 8" 4 '55 " 3 '37 " 7 Aluminum hydroxide 18 " 5 '09 " 4 '18 " 8 Boric acid 22 " 5 '53 " 4 '02 " 9 Aluminum oxide 10 " 4 '03 " 3 '27 "

As shown in Table 5, when using the shell as a flame retardant, it was shown that the flame retardancy rather excellent than when using magnesium hydroxide, sodium borate, sodium borate, aluminum hydroxide, boric acid, aluminum oxide. However, when antimony trioxide was used as a flame retardant, the flame retardancy was excellent, but it was not suitable as a flame retardant because harmful substances such as dioxane were emitted during combustion including halogen.

Comparative Example 10

Except for using 20% by weight of pure CaCO ₃ instead of shell as a flame retardant was carried out in the same manner as in Example 2, was carried out a total of six times to calculate the average physical properties. The results of egg coupling and physical property evaluation are shown in Table 6 and Table 7, respectively.

T ₁ T ₂ T ₃ Comparative Example 10 4" 7'24 " 3'08 "

Stress (MPa) Elongation at Break (%) Impact Strength (J / M) Flexural Strength (MPa) Comparative Example 10 a 13.20 172.0 437.991 0.5683 b 14.54 134.2 627.227 0.5690 c 13.80 148.3 685.096 0.5548 d 16.32 167.9 530.219 0.5809 e 13.91 160.9 552.987 0.5878 f 13.20 149.2 467.441 0.5789 Average 0.00 0.00 0.000 0.00

As shown in Tables 6 and 7, when using pure CaCO ₃ as a flame retardant, it was confirmed that inferior in the case of using a shell in terms of physical properties and flame retardancy.

The present invention utilizes a shell powder as a flame retardant in waste plastics that are discarded as wastes, thereby providing excellent mechanical properties, flame retardancy, no generation of toxic gases such as dioxins, and reducing manufacturing costs. Has the effect of the invention to provide a friendly flame retardant waste plastic resin composition.

Simple modifications and variations of the present invention can be readily used by those skilled in the art, and all such variations or modifications can be considered to be included within the scope of the present invention.

1 is a model diagram showing the principle that the waste plastic resin composition according to the present invention has flame retardancy.

2 is a photograph showing the combustion test results of the specimen prepared in Example.

Claims (2)

Waste plastic 60-90% by weight; And Shell powder 10-40% by weight; Flame retardant waste plastic resin composition, characterized in that consisting of. The flame retardant waste plastic resin composition according to claim 1, wherein the shell powder is surface-modified by n-cetyltrimethylammonium bromide (CTAB) or polyimine salt.