KR20040022984A - Nanocomposite-type flame retardant comprising non-halogen nitrogenous compounds and Method for manufacturing the same - Google Patents

Abstract

PURPOSE: Provided are a fire retardant containing non-halogen nitrogen compounds and layered silicate, and a preparation method thereof. The fire retardant reserves stable mechanical properties of a resin without using toxic halogen compounds, can be applied to electronic and industrial materials where fire retardants are needed. CONSTITUTION: The fire retardant comprises 80-90wt.% of a nitrogen compound containing no halogen component and 1-20wt.% of a layered silicate with nanometer size which has reduced polarity by treating with an organic compound. The layered silicate is selected from the group of montmorillonite, hectorite, vermiculite and saponite. The organic transformer is alkyl ammonium with the carbon chain number of 10 to 18. One or more of the nitrogen compounds are selected from the group of melamine derivatives consisting melamine, melamine phosphate and melamine cyanurate, the isocyanurate compounds consisting urea, urea derivatives, tris(2-hydroxyethyl)isocyanurate and triazine derivatives. The preparation method comprises the steps of: (a) treating with organic agent to reduce the polarity of the silicate layer; (b) mixing the 80-99wt.% of the nitrogen compound containing no halogen with 1-20wt.% of the layered silicate with less polarity from the step (a); and (c) conducting intercalation or delamination with the mixture from the step (b) at 180deg.C and under atmospheric pressure.

Description

Nanocomposite-type flame retardant comprising non-halogen nitrogenous compounds and method for manufacturing the same

The present invention relates to a flame retardant composition, and more particularly, by dispersing an amine-based nitrogen compound such as melamine and cyanurate in nano-sized layered silicate used as a filler, more flame retardant and mechanical than conventional conventional organic flame retardant The present invention relates to a non-halogen nitrogen compound-containing nanocomposite flame retardant composition having improved physical properties and a method of manufacturing the same.

Conventional flame retardant technology has been developed using halogen compounds such as chlorine and bromine, but various regulations on existing halogen flame retardants are strengthened due to the generation of various environmental pollutants derived from such halogen compounds and dioxin and furan, which are harmful to human body in case of fire. Recently, the demand for environmentally friendly non-halogen-based flame retardants is expanding, especially in Europe.

Currently, the main types of non-halogen flame retardants are phosphorus compounds, especially phosphate-based compounds, which are relatively low in flame retardancy compared to halogen compounds, and show a difference in flame retardancy due to different decomposition mechanisms upon combustion according to polymer type. Problems in forming a flame retardant product by adding a phosphorus-based flame retardant to plastic are poor molding surface and heat resistance. In addition, when left at a high temperature for a long time, there is a problem in that the decomposed phosphate ester compound is reduced to phosphoric acid and the like, and the physical properties of the molded article are drastically lowered. Such a change is particularly severe in oligomeric phosphate esters. Therefore, the method of adding the phosphorus-based flame retardant to the plastic is not effective in improving the flame resistance and heat resistance of the final resin.

In order to solve the above problems, a method has been recently attempted to improve the flame retardancy by adding a nitrogen flame retardant to a flame retardant product such as polyolefin resin or by using a mixture of a phosphorus flame retardant and a nitrogen flame retardant. For example, U. S. Patent No. 5,326, 805 discloses a technique of mixing flame retardant ammonium phosphate and nitrogen compound isocyanurate ester to impart flame retardancy.

However, the above-described techniques cause a decrease in the heat resistance of plastics due to the use of an organic flame retardant alone, as well as a dispersibility of micro units, and thus there is a limit in that the molded article cannot be provided with sufficient mechanical strength.

The present invention is to solve the conventional problems as described above, an object of the present invention, by dispersing a non-halogen nitrogen-based flame retardant in an organic layered silicate to prepare a nano-composite flame retardant dispersed in each component in nanometer size It provides a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition and a method for producing the same, which increase the heat resistance and flame retardancy of the polymer than the organic flame retardant, and impart mechanical strength that cannot be obtained with inorganic fillers such as microfibers. will be.

In order to achieve the above object, the non-halogen nitrogen compound-containing nanocomposite flame retardant composition according to the present invention is a layered silicate having reduced polarity by treating with 80 to 99 wt% of a nitrogen-free compound containing no halogen and an organic agent. Flame retardant composition comprising 1 to 20wt%, characterized in that the layered silicate has a size in nanometers. Here, the nano-size is the size of the molecule that is the minimum unit does not lose the intrinsic properties of the material.

In the non-halogen nitrogen compound-containing nanocomposite flame retardant composition according to the present invention, the layered silicate is selected from the group consisting of montmorillonite, hectorite, vermiculite and saponite.

In the non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition according to the present invention, the organic agent is characterized in that the alkyl ammonium having 10 to 18 carbon chains.

In the non-halogen nitrogen compound-containing nanocomposite flame retardant composition according to the present invention, the nitrogen-based compound is melamine derivatives, urea, urea derivatives, tris (2-hydroxy) including melamine, melamine phosphate, melamine cyanurate Isocyanurate derivatives comprising ethyl) isocyanurate (tris (2-hydroxyethyl) isocyanurate; THEIC), and triazine-based derivatives, characterized in that one or more selected from the group consisting of.

In addition, the method for producing a non-halogen nitrogen compound-containing nanocomposite flame retardant composition according to the present invention comprises: an organicization step of reducing the polarity of the layered silicate by treating with an organicizing agent; Mixing (b) 80 to 99 wt% of a halogen-free nitrogen-based compound and 1 to 20 wt% of the layered silicate having reduced polarity through the organic treatment of step (a); And (c) subjecting the mixture of step (b) to an intercalation or delamination reaction at atmospheric pressure or vacuum at 100 to 180 ° C., wherein the layered silicate of step (a) is in nanometers. It is characterized by having the size of the unit.

In the method for producing a non-halogen nitrogen compound-containing nanocomposite flame retardant composition according to the present invention, the layered silicate of step (a) is selected from the group consisting of montmorillonite, hectorite, vermiculite and saponite It features.

In the method for producing a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition according to the present invention, the organic agent of step (a) is characterized in that the alkyl ammonium having 10 to 18 carbon chains.

In the method for producing a non-halogen nitrogen compound-containing nanocomposite flame retardant composition according to the present invention, the nitrogen-based compound of step (b) is melamine derivatives, urea, urea, including melamine, melamine phosphate, melamine cyanurate At least one selected from the group consisting of derivatives, isocyanurate derivatives including tris (2-hydroxyethyl) isocyanurate, and triazine derivatives is used.

Representative layered silicates mainly used in unit organics or polymer / layered silicate nanocomposites are montmolylonite in the smectite family. Looking at the basic structure of montmolylonite, the outer silica tetrahedral sheet (silica tetrahedral sheet) is composed of a 2: 1 structure surrounding the octahedral sheet of aluminum or magnesium inside. In the octahedral sheet, it is partially substituted with magnesium or iron ions instead of aluminum ions, and the silicon ions of the tetrahedral sheet are partially substituted with aluminum ions, and are thus negatively charged. Therefore, in order to balance the total charge in the layer, the layers are filled with ions such as Na ⁺ and Li ⁺ . In particular, because of the hydrophilic structure in which very polar OH groups exist at the ends of the sheet, most lipophilic resins cannot be intercalated or layered silicates can be dispersed and dispersed into the resin.

Therefore, in order to disperse organic compound intercalation or layered silicate, it is necessary to use layered silicates with reduced polarity. For this purpose, in the present invention, organically modified layered silicate (OSL) is used by treatment with an organic agent. . In the present invention, a layered silicate organicated with alkylammonium having a large molecular size was used to increase the interlayer distance. As such, the term 'organization' refers to treatment with an alkylating agent, such as alkylammonium, to reduce the polarity of the inorganic layered silicates.

Most preferred alkyl ammonium for achieving the object of the present invention is alkyl ammonium having 10 to 18 carbon atoms. The organicization of the layered silicates occurs by cation exchange reactions between the protonated primary amines corresponding to cationic montmorillonite, hectorite, vermiculite or saponite.

The amount of the organic layered silicate used is preferably 1-20 wt% relative to the total flame retardant composition. If it is less than 1wt%, it does not provide enough surface area to disperse the nitrogen-based compound. If it is more than 20wt%, the layered silicate is agglomerated so that the physical mixing process is difficult and the flame-retardant effect of the nitrogen-based compound is reduced.

The flame retardant composition of the present invention is characterized in that the nitrogen-based compound is nanocomposited by intercalation between the layers of the layered silicate, or the layered layered silicate is de-laminated and dispersed between the nitrogen-based compounds. Here, the term 'nano composite' refers to a compound in which a nano-sized filler is combined with a matrix compound, and 1 nm is about the size of 3-4 atoms pasted.

The present invention will be described in detail through the following examples. However, the following examples are for illustrative purposes only, and the present invention is not limited thereto.

Example 1 Preparation of Nitrogen Compound / Layered Silicate Flame Retardant Composition

[Manufacture process]

1) Disperse 10 g of montmorillonite in 1000 ml of tertiary distilled water for a day.

2) Add 100 ml of an aqueous solution of alkyl ammonium and hydrochloric acid to the montmorillonite dispersion and conduct a cation exchange reaction at 85 ° C for 1 hour.

3) After washing three times or more with distilled water and dried for 2-3 days in a vacuum dryer to prepare an organic layered silicate powder.

4) 95 g of tris (2-hydroxyethyl) isocyanurate was added to the reflux reactor, and the temperature was raised to 150 ° C to dissolve sufficiently.

5) After 5 g of the organic layered silicate was added to the melt, an intercalation or delamination reaction was performed for 2 hours.

6) The reaction is cooled and ground to the desired particle size.

In the present invention, it was confirmed that the nanocomposite structure of the organic layered silicate and the nitrogen-based compound was formed through intercalation or delamination through distance change by X-ray diffraction analysis and morphology change through transmission electron microscope. X-ray diffraction analysis confirms by measuring a change in the interlayer distance of the layered silicate. When the nanocomposite is formed, the interlayer distance changes, but when the nanocomposite is not formed, the interlayer distance does not change.

The properties of the nanocomposite obtained according to the method for producing a flame retardant composition according to the present invention and the physical properties after application to the polypropylene molded product are shown in Table 1 below.

Evaluation item Assessment Methods Evaluation results Halogen content Elemental measurement 0% containing Structure of Nanocomposite X-ray diffraction, transmission electron microscope Confirmed intercalation or delamination PP molded products flame retardant UL-94 V-0 PP molded parts mechanical properties Tensile Strength, Heat Deflection Temperature Superior to conventional resin

(PP molded article: PP / APP / flame retardant composition / metal oxide of the present invention = 75/9/15/1)

As shown in Table 1, the flame retardant composition according to the present invention did not contain any halogen as a result of element measurement, the nanocomposite structure was confirmed that the interlayer distance of the layered silicate was changed by X-ray diffraction as described above.

In addition, when applied to PP, it was confirmed that a molded article of flame retardant V-0 grade having excellent mechanical properties including tensile strength and thermal stability than the conventional one can be obtained.

According to the present invention, a nanocomposite flame retardant composition composed of a non-halogen nitrogen compound and a layered silicate, while maintaining a stable mechanical property than using a conventional phosphorus- and / or nitrogen-based flame retardant alone without using harmful halogens, Excellent flame retardancy can be imparted to the resin, which can be applied to various polymer applications requiring flame retardancy such as electric and electronic materials and industrial materials.

In addition, the flame retardant composition according to the present invention can act as a barrier to inhibit the permeability of water or gas can maintain the physical properties of the resin, as well as used alone and mixed with a phosphorous flame retardant when applied to a polyolefin resin system Lower flame retardancy due to synergy can be ensured.

In addition, by using the method for producing a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition according to the present invention, it is possible to effectively produce excellent flame retardant compositions having the same role as described above.

Claims (8)

A flame retardant composition comprising 80 to 99 wt% of a halogen-free nitrogen-based compound and 1 to 20 wt% of a layered silicate whose polarity is reduced by organizing with an organic agent. A non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition, characterized in that the layered silicate has a size in nanometers. The method of claim 1, In the non-halogen nitrogen compound-containing nanocomposite flame retardant composition according to the present invention, the layered silicate is selected from the group consisting of montmorillonite, hectorite, vermiculite and saponite. The method of claim 1, The organic agent is a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition, characterized in that the alkyl ammonium having 10 to 18 carbon chains. The method of claim 1, The nitrogen-based compound is a melamine derivative, including melamine, melamine phosphate, melamine cyanurate, urea, urea derivative, isocyanurate derivative including tris (2-hydroxyethyl) isocyanurate, and triazine Non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition, characterized in that at least one selected from the group consisting of derivatives. An organication step (a) of reducing the polarity of the layered silicate by treating with an organizing agent; Mixing (b) 80 to 99 wt% of a halogen-free nitrogen-based compound and 1 to 20 wt% of the layered silicate having reduced polarity through the organic treatment of step (a); And A method of manufacturing comprising the step (c) of the step (b) to the intercalation or delamination reaction at 100 to 180 ℃ normal pressure or vacuum, Method of producing a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition, characterized in that the layered silicate of step (a) has a size in nanometers. The method of claim 5, The layered silicate of step (a) is a method for producing a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition, characterized in that selected from the group consisting of montmorillonite, hectorite, vermiculite and saponite. The method of claim 5, The method of preparing a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition, characterized in that the organic agent of step (a) is alkyl ammonium having 10 to 18 carbon chains. The method of claim 5, The nitrogen-based compound of step (b) is melamine, melamine phosphate, melamine derivatives including melamine cyanurate, urea, urea derivative, isocyanurate including tris (2-hydroxyethyl) isocyanurate A method for producing a non-halogen nitrogen-based compound-containing nanocomposite flame retardant composition, characterized in that at least one selected from the group consisting of derivatives and triazine derivatives.