JPS5946532B2 - Flame retardant resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flame-retardant resin composition with excellent heat resistance.

More specifically, carboxyl group, acid anhydride (group),
A resin composition (I) obtained from a resinous component having one or more functional groups selected from hydroxyl groups alone or in a mixture with a rubber component, and a hydroxyl group that can react with the functional groups in (I). , a phenolic hydroxyl group, a carboxyl group, an acid anhydride (group), or a mixture of two or more of them (■) containing one or more of the following: This invention relates to a flammable resin composition.
Due to its excellent properties, so-called styrene-based resins are used in a wide variety of fields such as household electrical appliances, automobile parts, construction materials, and various other molded products.

However, styrenic resins, like many other synthetic polymers, are easily flammable and pose a high risk of fire.
On the other hand, in recent years, there has been a demand for synthetic polymers to be flame retardant, especially for household light electrical parts.

Furthermore, legal regulations regarding flame retardation are becoming stronger in each country from the standpoint of consumer protection. Currently, flame retardant synthetic polymers are mainly made by adding compounds containing halogens, phosphorus, etc., and flame retardants such as antimony trioxide. Although flame retardance can be achieved, there is a tendency for other physical properties to be adversely affected.

In particular, when low-molecular-weight flame retardants are added, there are problems such as a decrease in heat distortion temperature, the generation of corrosive gas during molding, the toxicity of substances exuded from the resin during long-term use, and the sustainability of flame retardancy. has been done. On the other hand, in the method of making flame retardant by copolymerization, compounds containing halogen or phosphorus are used as flame retardant imparting compounds, but they do not have the ability to copolymerize with other monomers or the desired physical properties of the resulting resin composition. Because it is difficult to equip them, there are still few in actual use, and many of them are expensive. The present inventors have made extensive studies to improve the above drawbacks, and as a result, have found that: By introducing a functional group into a resinous component and combining it with a flame retardant containing a functional group that is reactive with this,
It has been found that a resin composition with excellent flame retardancy, heat resistance, and safety can be easily obtained.

That is, the present invention comprises a rubber component of 0 to 40% by weight, a hydroxyl group,
1 selected from carboxyl group and acid anhydride (group)
100 to 6 resinous components having species or two or more kinds of functional groups
98 to 60 parts by weight of resin (1) obtained from 0% by weight and (
1) Single or mixture of two or more halogen flame retardants containing one or more of hydroxyl group, phenolic hydroxyl group, carboxyl group, and acid anhydride (group) that can react with the functional groups in 1) It is a flame-retardant resin composition with excellent heat resistance, consisting of 2 to 40 parts by weight, and the resinous component is a vinyl aromatic monomer and one or two vinyl monomers copolymerizable therewith. A copolymer consisting of 1 to 55 functional groups per weight average molecular weight of 10,000, or a copolymer consisting of 1 to 55 functional groups selected from hydroxyl group, carboxyl group, and acid anhydride (group) per 10,000 weight average molecular weight. Contains 3% by weight or more of a copolymer that has been post-treated so as to have 3% by weight or more based on the total resinous components, and 99 to 35% by weight of a vinyl aromatic monomer and one type of vinyl monomer copolymerizable therewith. Or, it is characterized by being a composition consisting of 1 to 65% by weight of two or more types.

The post-treatment of the copolymer referred to herein refers to an operation of converting a functional group in the copolymer into another functional group by a treatment such as saponification. Styrene is most suitable as the vinyl aromatic monomer, but various substituted styrene derivatives such as α-methylstyrene, P-methylstyrene, and 0-chlorostyrene can also be used, and two or more types can be used simultaneously. You can also.

There are no particular restrictions on the vinyl monomer that can be copolymerized with the vinyl aromatic monomer, but examples include acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, 2-hydroxyethyl methacrylate,
These include acrylic acid, methacrylic acid, maleic anhydride, vinyl acetate, and 2-chlorovinyl ether, and there is no problem in using two or more of them at the same time. The halogen flame retardants having a hydroxyl group according to the present invention include 2,2-bis(3,5'-dibromo-4'-1β-oxyethoxyphenyl)propane and 2,2-bis(bromomethyl)-
1◆3-Propanediol, etc., and has a phenolic hydroxyl group...Rogen-based flame retardants include tetraprombisphenol A1, tetraprombisphenol S, tripromphenol, etc., and also halogen-based flame retardants, which have a carboxyl group. The flame retardant is tribromobenzoic acid, tribromoacetic acid, etc., and the halogen flame retardant having an acid anhydride (group) is tetrabromophthalic anhydride, chlorendic acid anhydride, etc.

The combination of the functional groups in the resin (1) and the flame retardant () in the present invention is not particularly limited as long as they can react, but examples include hydroxyl groups, Examples include combinations of phenolic hydroxyl groups, carboxyl groups, and acid anhydrides (groups).

As the rubber component in the present invention, those commonly used in the production of impact-resistant polymers may be used, such as polybutadiene rubber, butadiene-styrene rubber, ethylene-propylene rubber acrylic rubber, and chloroprene rubber. etc. can be applied. In the present invention, the resinous component is composed of a vinyl aromatic monomer and one or more vinyl monomers copolymerizable with the vinyl aromatic monomer, and includes a hydroxyl group, a carboxyl group, and an acid anhydride (group). 1 or 2 to choose from
1 to 5 of more than 1 species per 10,000 weight average molecular weight
5 or a copolymer post-treated to have the above-mentioned functional groups in an amount of 3% by weight or more based on the total resinous component, and 99 to 35% by weight of a vinyl aromatic monomer. It is a resin composition consisting of 1 to 65% by weight of one or more polymerizable vinyl monomers.

The copolymer having the above-mentioned functional group includes the above-mentioned acrylic acid, methacrylic acid, maleic anhydride, and 2-hydroxyethyl methacrylate as all or a part of the vinyl monomer copolymerizable with the vinyl aromatic monomer. It is obtained by using a monomer having a functional group selected from a hydroxyl group, a carboxyl group, and an acid anhydride (group), and copolymerizing this with a vinyl aromatic monomer by a commonly known method. Alternatively, it can be obtained by converting a copolymer of a vinyl aromatic monomer and, for example, a (meth)acrylic acid ester into the above functional group by subjecting it to a post-treatment such as hydrolysis. Here, the amount of the copolymer having a functional group corresponds to the amount of the functional group it has and the type and amount of the functional group-containing flame retardant, but it is 3% by weight based on the resinous component.
If the above is not used, the heat resistance that is the objective of the present invention,
A resin composition with excellent safety cannot be obtained. Furthermore, the functional group in the copolymer having a functional group has a weight average molecular weight of 1000.
Even if the ratio is less than 1 per 0, the desired heat resistance and safety cannot be imparted to the flame-retardant resin composition. In addition, if there are too many functional groups, the physical properties of the flame-retardant resin composition may be deteriorated. Next, these resinous components include, in addition to the copolymer having the above-mentioned functional group, each homopolymer of the vinyl aromatic monomer (a) or the vinyl monomer (b) copolymerizable therewith. Combining or combining two or more types (
This is a resin composition containing a copolymer of (a) or (b) other than the copolymer of a) or (b) and a copolymer having a functional group.

There are no particular limitations on the method of polymerizing these resin compositions, and radical polymerization, cationic polymerization, anionic polymerization, etc. can be used.

Next, in the method of mixing resinous components and rubbery components,
Similar to the synthesis of so-called high-impact polystyrene and ABS resins, there is a graft polymerization method in which monomers (a) and/or (b) are homopolymerized or copolymerized in the presence of a rubbery component, or a resinous component and a rubbery component. There is a blending method of mechanically mixing the two, and the method is not particularly limited.

On the other hand, the halogen flame retardant used in the present invention is a compound containing a functional group that is reactive with the functional group in the resin (1), and the amount used depends on the desired degree of flame retardation. However, in the flame retardant resin composition of the present invention,
If it is less than 2 parts by weight, the purpose of flame retardation cannot be achieved, and if it is more than 40 parts by weight, it will be an excessive amount and will deteriorate the physical properties of the resin, especially the thermal stability.

The flame-retardant resin composition of the present invention can be produced by adding the above-mentioned halogen-based flame retardant () at any time during the production of the resin (1), or by adding the halogen-based flame retardant to the resin (1) obtained. It can also be easily produced by mixing with a flame retardant (2) using a conventional mixing device, such as a hot roll, a Banbury mixer, or an extruder.

In addition, when reacting the resinous component with the functional group in the halogenated flame retardant, tetra-n-butylammonium bromide,
There is no particular problem in adding a reaction accelerator such as 2-ethyl-4-imidazole or boron trifluoride to the extent that the physical properties of the flame-retardant resin composition are not impaired. In addition, a halogen-based flame retardant that does not react with the functional groups in the resin (1),
There is no particular problem in using a phosphorus-based flame retardant and an inorganic flame retardant such as antimony trioxide in combination.

The details of the present invention will be described below with reference to Examples, and the flammability in the Examples, Reference Examples, and Comparative Examples was measured based on Subdivision No. 94 established by Underriders Laboratory, USA.

The dimensions of the test piece are 1/8 inch thick, 1/2 inch wide, and 6 inches long. All parts in the example sentences refer to parts by weight. Reference Example 1 The above composition was charged into a closed reaction vessel equipped with a stirring device, and the temperature was raised to 72°C until the rubber component was completely dissolved, and bulk polymerization was carried out for 3 and a half hours.

Furthermore, an aqueous dispersant solution prepared in advance by mixing 100 parts of water, 4 parts of magnesium hydroxide, and 0.002 parts of sodium lauryl sulfate was added, and the mixture was stirred and suspended. then 120
The temperature was raised to .degree. C., and suspension polymerization was carried out for 5 hours. The obtained particles were washed with water and then dried. This is called resin A. In addition, this resin A was pressed in a hydraulic press (200°C/10 minutes, gauge pressure 100kg/
Cd) was press-formed and cut into test pieces, and the flammability was measured.

Reference Example 2 A closed type reaction equipped with a stirring device containing an aqueous dispersant solution in which the above-mentioned composition that burns well is mixed in advance with 100 parts of water, 4 parts of magnesium hydroxide, and 0.002 parts of sodium lauryl sulfate. Pour into a container and suspend well.

Thereafter, suspension polymerization was carried out at 70°C for 10 hours. The obtained particles were washed with water and then dried. This will be referred to as resin B. The flammability of this resin B was measured in the same manner as in Reference Example 1, and it burned well. Reference Example 3 The above composition was charged into a closed reaction vessel equipped with a stirring device, and the temperature was raised to 85°C until the rubber component was completely dissolved, and bulk polymerization was carried out for 3 hours.

Furthermore, an aqueous dispersant solution prepared in advance by mixing 100 parts of water, 4 parts of magnesium hydroxide, and 0.002 parts of sodium lauryl sulfate was added, and the mixture was stirred and suspended. Thereafter, the temperature was raised to 120°C, and suspension polymerization was carried out for 10 hours. The obtained polymer particles were washed with water and then dried. This will be referred to as resin C. Furthermore, this resin C
The flammability of the material was measured in the same manner as in Reference Example 1, and it burned well. Reference Example 4 A polymer was obtained by polymerization and drying under the same conditions as Reference Example 3.

The obtained polymer had a weight average molecular weight of 55,000 as measured by gel permeation chromatogram (GPC), and the weight average molecular weight of 2-hydroxyethyl methacrylate was 19.8.
It contained %. (15 hydroxyl groups per weight average molecular weight of 10,000) This is referred to as Resin D. The flammability of this Resin D was measured in the same manner as in Reference Example 1, and it burned well. Reference Example 5 100 parts of benzene was placed in a reactor equipped with a stirring device, a reflux device, and a monomer dropping device, and the temperature was raised to 70°C.

While maintaining this temperature, 200 parts of benzene, 52 parts of styrene and α・α5-
A solution containing 0.5 part of azobisisobutyronitrile and a solution containing 49 parts of maleic anhydride dissolved in 200 parts of benzene were continuously added to the reactor over a period of 2 hours to carry out polymerization. Thereafter, the temperature was maintained at 70°C for an additional 2 hours. The resulting benzene-insoluble polymer was filtered off, washed with hot benzene, and then dried in vacuum. The resulting polymer had a weight average molecular weight of 22,000 as measured by gel permeation chromatogram (GPC) and contained 54% maleic anhydride. (55 acid anhydrides per weight average molecular weight of 10,000) This is referred to as Resin E. In addition, the flammability of this resin E is shown in Reference Example 1.
When measured in the same manner as above, it burned well. Example 1 65 parts of the resin C obtained in Reference Example 3, 3 parts of the resin El obtained in Reference Example 5, and 22 parts of tetrapromubisphenol A were melt-blended at 200°C for 5 minutes using a Brabender plastogram, and then press-molded (200°C). °C/10 minutes,
100k9/Cd), a specified test piece was prepared by cutting, and the physical properties were measured using a conventional method. As a result, the tensile strength was 395.
kg/Cd, tensile elongation at break 9%, heat distortion temperature (load 18
．． 6k9/Cd) The flammability was -1 at 70°C.

Comparative Example 1 Physical properties were measured in the same manner as in Example 1 except that resin B was used instead of resin E in Example 1, and the flammability was V-2.
Furthermore, the heat distortion temperature was as low as 58° C., and the flame retardancy and heat resistance were inferior to that of Example 1.

Example 2 62 parts of the resin A obtained in Reference Example 1, parts of the resin D2O obtained in Reference Example 4, and 18 parts of tetrabromo phthalic anhydride were melt-blended in the same manner as in Example 1, and then a test piece was prepared and the physical properties were determined. When measured, the tensile strength was 4651<9/CrA,
Tensile elongation at break is 10%, heat distortion temperature is 74℃, flammability is V
It was -1.

Comparative Example 2 The physical properties were measured in the same manner as in Example 2 except that Resin B was used instead of Resin D in Example 2, and the flammability was V-2 and the heat distortion temperature was as low as 68°C. Compared to Example 2, the fire resistance and heat resistance are inferior.

The molding conditions and measurement conditions in the Examples and Comparative Examples are as follows.

◎Molding conditions (a) Plastic pender - Blastogram (b) Press molding (c) Extrusion (d) Injection molding ◎Measurement temperature (a) Flammability UL standard Subject number 94 Test piece length 1/8 inch, width 1 /2 inches, length 6 inches (b) Tensile strength and tensile elongation at break (c) Heat distortion temperature

Claims (1)

[Claims] 1 Consisting of a vinyl aromatic monomer and one or more vinyl monomers copolymerizable with it, one or two selected from hydroxyl groups, carboxyl groups, and acid anhydrides (groups).
1 to 5 functional groups per 10,000 weight average molecular weight
5 or a copolymer post-treated to have the above-mentioned functional groups in an amount of 3% by weight or more based on the total resinous component, and 99 to 35% by weight of a vinyl aromatic monomer. Resin (I) obtained from 100-60% by weight of a resinous component consisting of 1-65% by weight of one or more polymerizable vinyl monomers and 0-40% by weight of a rubbery component (I) 98-98%
60 parts by weight and hydroxyl groups, phenolic hydroxyl groups, carboxyl groups, acid anhydrides (
A flame-retardant resin composition comprising 2 to 40 parts by weight of a halogen flame retardant alone or a mixture of two or more (II) containing one or more of the following.