JPS62109849A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition having high flame-retardancy and solidifying rate, short molding cycle and excellent physical properties such as moisture absorption, etc., by compounding a polyamide resin with melamine cyanurate and a compound selected from silica, PET, etc. CONSTITUTION:The objective composition can be produced by compounding (A) 100pts.(wt.) of a polyamide resin with (B) 1-20pts. of melamine cyanurate and (C) 0.01-3pts. (in total) of a compound selected from (C1) an inorganic compound containing SiO2 as an essential component and composed of (SiO2)m, (MgO)n, (Al2O3)l, (CaO)K, (H2O)J, (C2) the compound of formula I (n is 2-4), (C3) the compound of formula II (Me2 is Na or K; X and Y are group of formula III or IV (R1 and R2 are H or CnH2n+1; n is 1-6) and (C4) the compound of formula V (Z is group of formula III or IV). The molded article of the composition has fine and uniform crystal structure, is free from dimensional change in moisture absorption and annealing and has various other improved physical properties.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a polyamide resin composition (flame-retardant resin composition) having high flame retardancy and improved processability.

"Prior Art and Problems" As is well known, nylon 6.6 has excellent thermal properties,
Due to its mechanical, electrical, and chemical properties, it is widely used as an industrial resin. In particular, nylon 6.6 is preferably used as a material for electrical parts because it is self-extinguishing.

However, in recent years, the demand for flame retardant plastic materials for electronic and electrical equipment applications has become stricter, and nylon 6
．． There are few cases in which a higher degree of flame retardancy is required even in the case of UL-94V-Oi. Consideration is being given to imparting high flame retardancy.

For example, the addition of the following compounds has been proposed.

(al Halogen compounds, (1)) Melamine compounds (e.g.
No. 41745).

(c) Cyanuric acid compounds (e.g., JP-A-50-
No. 105744).

(cL) Equimolar adduct of melamine and cyanuric acid (for example, JP-A-53-31759).

When considering these from the viewpoint of deterioration, decomposition, and foaming of additives during molding, method (d) is relatively good.

However, even in the method (d), as the residence time of the resin in the molding machine becomes longer, the additive decomposes and the appearance of the molded product is impaired.

"Means for solving the problem" In order to solve the above problem, it is possible to shorten the molding cycle per shot (by shortening the residence time), the above-mentioned deterioration will not occur, and of course productivity will be improved. From the viewpoint of improving flame retardancy and reducing costs, the inventors sought to obtain a composition that maintains high flame retardancy and shortens the molding cycle. I wanted to know that the composition of the formulation can achieve the purpose.

That is, melamine cyanurate and one of the compounds represented by the structural formulas (1) to (1■) below are added to the polyamide resin.
7 (1) Sin□ is an essential component, and (Sin□) m%
'(MgO)n% (At203)tl(CaO)k and (H2O)J Inorganic compound consisting of one or more components, n = 2 or 4 compound.

(iii) However, Me2 is selected from Na, , K, and X.

-〇nH2n+1 (zl=1~6)] Mojikuha (n=1
~6)].

However, Me 3 is selected from Mg, Ca, and -
CnH2n+, (n=1~6) ]Mosukuu(
n = 1 to 6)] ("action" - In the above configuration, the polyamide resin used includes a lactam with three or more membered rings, a polymerizable ω-aba) acid,
A polyamide obtained by polycondensation of dibasic acid and cyamine or the like can be used.

(If Al, nylon 6, nylon 10. nylon 1
1. Nylon 12, Nylon 6.6, Nylon 6.10
．． Examples include nylon 6.12, but polyamide copolymers (for example, nylon 6/6゜6 copolymer, nylon 6/6.10 copolymer, etc.) may also be used (or two or more polyamide resins). In addition, cyanuric acid melamine is an equimolar reaction product of cyanuric acid and melamine, for example, an aqueous solution of cyanuric acid and an aqueous solution of melamine are mixed and heated at a temperature of 70 to 100℃. It can be obtained by reacting under stirring with water and filtering the produced precipitate.

Examples of the compound (1) include silica and Merck, and examples of the compound (11) include PET powder.

The blending ratio of each of the above components is 100% polyamide resin.
It is preferable that the total amount of melamine cyanurate is 1 to 20 parts by weight, and the total amount of the compounds selected from compounds (1) to (1) is 0.01 to 3 parts by weight.

In this blending ratio, if the amount of melamine cyanurate added is small, there will be no flame retardant effect (on the contrary, if it is too large, the physical properties will deteriorate, which is not preferable. Also, if the total amount of the compounds (1) to (1v) is 0 If the amount is less than .01'l, the molding cycle cannot be shortened, and if it is more than 3'l, the fluidity and impact properties will decrease, which is not preferable.

As described above, the composition of the present invention has a fast solidification rate (short molding cycle), maintains a high degree of flame retardancy, and has a fine and uniform crystal structure in the molded product. Therefore, there is little dimensional change during moisture absorption and annealing (and other physical properties are also good.In contrast, sodium benzoate and aluminum bala-t-13u-benzoate, which are commonly used to increase the solidification rate, However, not only the molding cycle cannot be shortened, but also the physical properties are seriously deteriorated (it can be seen that the composition of the present invention is uniquely effective).

"Example" (Synthesis of melamine cyanurate) 80 tons of distilled water, 72.52 kg of cyanuric acid, and 2.58 kg of cyanuric acid were placed in a stainless steel autoclave with an internal volume of 200 tons and replaced with N2, and reacted at 85°C for 1 hour. . After the reaction, the white suspension was put into a cloth filter and passed through a 25" centrifuge to separate the solids and water. The solids were then dried in a vacuum dryer at 80°C for two days and nights.
4.611 tons of white powder was obtained. This powder was confirmed to be cyanuric acid melahan from the infrared absorption spectrum.

(Manufacture of composition) Melamine cyanurate synthesized by the above method and the third component shown in the table were mixed with nylon 6.6 in the proportion shown in the table, and the mixture was heated in a 3Qauaφ co-directional twin screw extruder (Ikegu Iron Works Co., Ltd.). Manufactured PC
M-30) was used to pelletize. The obtained pellets were subjected to the following various tests (Examples 1 to 8).

On the other hand, as shown in the table, those that lack cyanuric acid melamine or the third component, or have an inappropriate aluminum texture,
Or, those whose blending ratios deviate from those of the present invention were cited as comparative examples (Comparative Examples 1 to 5) fl (Test method) - Flammability---5' x 1/2' x 1/
16" specimens were injection molded and tested according to UL-94.

・Dupont impact strength---1,6X120X12
A 0(u) flat plate is injected into an acid mold, and the impact strength is determined using a 1/4'H tip.

・Molding shrinkage rate---1,6X 120X
Please make sure to measure with a 120 (Lll) flat plate. Annealing was carried out in silicone oil at 170°C x 1hr. - High cycle steel - 450mm diameter and 3mm thick
Outside diameter 7y on disk of U.

Circular diameter 2.5U and length 15M cylindrical body integrated The shaped product is cooled. Molding by changing the cooling time, The shape of the bottle hole inside is good. I decided whether I liked it or not.

As can be seen from the table, the composition of the present invention maintains a high degree of flame retardancy, and the molding cycle is also significantly shortened. Also,
It can be seen that the physical properties and dimensional stability are also good.

On the other hand, as can be seen from the comparative examples, crystal nucleating agents outside the scope of the present invention not only do not have the effect of improving the cycle, but also have poor DuPont impact strength and poor dimensional stability. Furthermore, when the blending ratio is outside the range of the present invention, some of the performance is markedly inferior and is therefore unsuitable.

"Effects of the Invention" As explained above, the resin composition according to the present invention has a high solidification rate, requires a short molding cycle, maintains a high degree of flame retardancy, and has crystallization of molded products. Since the structure is fine and uniform, the size during moisture absorption and annealing is small (and other physical properties are also good, so it is possible to efficiently obtain high-quality molded products.

Claims (2)

[Claims] (1) Melamine cyanurate and the following (
A flame-retardant resin composition containing one or more compounds among the compounds represented by the structural formulas i) to (iv). (i) SiO_2 is an essential component, (SiO_2)_m
, (M_gO)_n, (Al_2O_3)_l, (Ca
O) An inorganic compound consisting of one or more components of _k and (H_2O)_J. (ii) ▲There are mathematical formulas, chemical formulas, tables, etc. ▼ Compounds where n = 2 or 4. (iii) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ However, Me_2 is selected from Nε, K, and X, Y are ▲ Mathematical formulas, chemical formulas, tables, etc. ~6)] or ▲
There are mathematical formulas, chemical formulas, tables, etc.▼[R_2 is -H or -CnH_2_n_+_1 (n=1 to 6)]. (iv) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ However, Me_3 is selected from Mg, Ca, and Z is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [R_1 is -H or -CnH_2_n_+_1 (n = 1 to 6 )] or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [R_2 is -H or -CnH_2_n_+_1 (n = 1 to 6)]. (2) The blending amount of melamine cyanurate is 1 to 20 parts by weight per 100 parts by weight of the polyamide resin, and (i) to (i
The flame-retardant resin composition according to claim 1, wherein the total amount of the compounds selected from v) is 0.01 to 3 parts by weight.