JPH0312451A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition having improved heat resistance, impact resistance, water-vapor resistance and appearance of molded article by blending a resin composition consisting of nylon 46 resin and a rubber modified styrene- based polymer with an acid anhydride group-containing unsaturated compound. CONSTITUTION:100 pts.wt. resin composition comprising (A) 40-95wt.%, preferably 50-90wt.% nylon 46 resin having preferably 1.5-5.5 relative viscosity and (B) 60-5wt.%, preferably 50-10wt.% rubber modified styrene-based polymer having preferably 0.5-40g/10 minutes MFR value prepared by polymerizing an aromatic vinyl compound with a vinyl cyanide compound in the weight ratio of the former/the latter=(95/5)-(50/50), preferably (90/10)-(55/45) in the presence of a butadiene-based rubber-like polymer is blended with (C) 0.001-5 pts.wt., preferably 0.005-4 pts.wt. acid anhydride group-containing unsaturated compound (preferably maleic anhydride).

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a resin composition that has excellent heat resistance, impact resistance, moisture resistance, and improved appearance of molded products, and has excellent mechanical properties. In addition to its thermal properties, it has improved impact resistance, moisture resistance, and molded product appearance, making it applicable to a wide range of fields such as automobiles, electrical/electronic, and machinery through injection molding, extrusion molding, blow molding, foam molding, etc.

(Prior Art) Nylon 46 resin consisting of tetramethylene diamine, adipic acid and functional derivatives thereof is already a well-known polyamide. For example, Japanese Patent Publication No. 60-8248 and Japanese Patent Publication No. 60-28843 disclose methods for manufacturing nylon 46 resin products. This nylon 46 resin is also known to have excellent properties as an engineering plastic, particularly excellent heat resistance. For example, its melting point is 295°C, and nylon 66 has a melting point of 26
It is not only higher than 0°C, but also higher than 285°C for polyphenylene sulfide. High crystal ratio change, high crystallization speed change, heat distortion temperature (4.5Kg/ci load)
The temperature is 290°C, which is the highest value among engineering plastics. It also has excellent mechanical strength such as tensile strength and bending strength, sliding properties, and fatigue resistance.

However, the Izod impact strength of nylon 46 resin is 7@-cab/cm, which is not necessarily a high value for engineering plastics. As a method to improve this drawback, a method of blending a modified styrene copolymer containing functional groups such as carboxyl groups and acid anhydride groups was proposed in JP-A-62-17.
It is disclosed in Japanese Patent No. 9562.

Furthermore, compared to nylon 6 and nylon 66, it has a high concentration of amide groups, so it has a drawback of high water absorption.

As a method for improving this drawback, JP-A-63-162750 discloses a method of blending a rubbery polymer, an unsaturated compound containing a functional group, and a peroxide having a peroxide bond. However, even when these methods are implemented, the performance is not necessarily satisfactory, and the heat distortion temperature, which is one index of heat resistance, is significantly lowered, and the appearance of the molded product is not good.

(Problems to be Solved by the Invention) In view of the above circumstances, an object of the present invention is to improve the impact resistance, moisture resistance, and appearance of molded products without impairing the excellent properties of nylon 46 resin, and to improve the appearance of molded products useful in the molding industry. The objective is to obtain a resin composition.

(Means for Solving the Problems) As a result of intensive research in order to solve the above problems, the present inventors found that (A) Nylon 46 resin 40-95% heavy weight;
(B) A resin composition consisting of 60 to 5% by weight of a styrenic polymer obtained by polymerizing an aromatic vinyl compound and a vinyl cyanide compound in the presence of a rubbery polymer. To 100 parts by weight (C) acid anhydride. The present invention has been achieved, the gist of which is a resin composition containing 0.001 to 5 parts by weight of a group-containing unsaturated compound.

The nylon 46 resin used as component (A) in the present invention refers to polyamides and polyamide mixtures whose main constituent units are polyamides made of tetramethylene diamine, adipic acid, and functional derivatives thereof. A part of the adipic acid component or the tetramethylene diamine component may be replaced with another copolymer component.

The copolymerization component or mixed component is not particularly limited, and known amide group-forming components can be used.

Representative examples of copolymerized components include 6-aminocaproic acid, 1
Amino acids such as 1-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid, lactams such as ε-caprolactam and ω-lauryllactam, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2.2. 4-/2.4.4-trimethylhexamethylenediamine, 5-methylnonamethyldiamine, metaxylenediamine, baraxylenediamine, 1.3-bis(aminomethyl)cyclohexane, 1,
4-bis(aminomethyl)cyclohexane, 1-amino-3-aminomethyl-3,5,5-)limethylcyclohexane, bis(3-methyl-4-aminocyclohexyl)methane, 2,2-bis(4- aminocyclohexyl)
Diamines such as propane, bis(aminopropyl)piperazine, and aminoethylpiperazine and adipic acid, speric acid, azelaic acid, sebacic acid, dodecanniic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-
Examples include dicarboxylic acids such as methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, and diglycolic acid.

Any method can be used for producing the nylon 46 resin used in the present invention. For example, the method disclosed in Japanese Patent Publication No. 60-28843, Japanese Patent Publication No. 60-8248, Japanese Patent Application Laid-open No. 58-83029, and Japanese Patent Application Laid-Open No. 61-43631, that is, first, a preform with a small amount of cyclic terminal groups is used. Polymers are produced under specific conditions and then solid-phase polymerized in a steam atmosphere to produce high-viscosity nylon 46 resin, or in polar organic solvents such as 2-pyrrolidone or N-methylpyrrolidone. It is particularly preferable to use those obtained by heating.

There is no particular restriction on the degree of polymerization of the nylon 46 resin used in the present invention, but the relative viscosity is 1.5 to 1.5 when measured at 25°C using 96% sulfuric acid and concentrated Jt 1 g/dt.
5.5, preferably a nylon 46 resin in the range of 2.0 to 4.5. If the relative viscosity exceeds 5.5, not only the fluidity of the composition deteriorates, but also the variation in its mechanical and thermal properties increases, which is not preferable. If the relative viscosity is lower than 1.5, the mechanical strength of the composition will be low.

In the resin composition of the present invention, the proportion of nylon 46 resin used is 40 to 95% by weight, or 50 to 90% by weight. If it is less than 40% by weight, molding processability, appearance of the molded product, etc. may deteriorate, which is not preferable. - side, 95% by weight
Exceeding this is not preferable because improvements in impact resistance, moisture resistance, etc. will not be sufficient.

The rubbery modified styrenic polymer as component (B) used in the present invention is obtained by polymerizing an aromatic vinyl compound and a vinyl cyanide compound in the presence of a rubbery polymer. Methods for obtaining component (B) include known polymerization methods such as emulsion polymerization, solution polymerization, bulk polymerization, suspension polymerization, bulk-solution polymerization, bulk-suspension polymerization, emulsion-suspension polymerization, and rubbery polymers. Mechanical blending of a styrene polymer and a styrene polymer can be used, but an emulsion polymerization method is particularly preferred.

All known polymerization initiators, polymerization solvents, polymerization initiation aids, suspending agents, emulsifiers, etc. used in the above various polymerization methods can be used.

The aromatic vinyl compound referred to in the present invention includes styrene,
α-Methylstyrene, methylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, monobromstyrene, dibromstyrene, tribromstyrene, p
-Tertiary-butylstyrene, ethylstyrene, vinylnaphthalene and the like, preferably styrene and α-methylstyrene. These may be used alone or in combination of two or more.

Examples of vinyl cyanide compounds include acrylonitrile and methacrylatetrile. The usage ratio of the aromatic vinyl compound and vinyl cyanide compound in the component (B) is aromatic vinyl compound/vinyl cyanide compound -9515 to 5015.
0, preferably within the range of 90/10 to 55/45% by weight.

Furthermore, other vinyl compounds can be copolymerized within a range that does not impair the object of the present invention. Other copolymerizable vinyl compounds include acrylic acid alkyl esters. Examples of acrylic acid alkyl esters include acrylic acid alkyl esters and methacrylic acid alkyl esters, which are used as TFL or in combination of two or more types.

Examples of acrylic acid alkyl esters include methyl acrylate, ethyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate-1-, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, and benzyl. Acrylic acid alkyl esters such as acrylates and methyl methacrylate-1, ethyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl Examples include methacrylic acid alkyl esters such as methacrylate and pendyl meccrate.

The amount of these other copolymerizable vinyl compounds used is (B)
0 to 50% by weight in the components excluding the rubbery polymer,
It can be used preferably in a range of 0 to 40% by weight.

As the butadiene-based rubbery polymer to be present during the polymerization of the aromatic vinyl compound and the vinyl cyanide compound, butadiene, butadiene-isoprene copolymer, butadiene-
Examples include diene rubbers such as acrylic acid ester copolymers, butadiene-styrene copolymers, butadiene-acrylonitrile copolymers, styrene-butadiene block copolymers, styrene-isoprene-butadiene block copolymers, etc. . These butadiene-based rubbery polymers can be used alone or in combination of two or more. All of these butadiene-based rubbery polymers are preferably used. these(
B) The amount of rubber polymer in component is 10 to 5 from an industrial point of view.
It is preferable to use it in a range of 0% by weight.

The acid anhydride group-containing unsaturated compound of component (C) in the present invention includes maleic anhydride, itaconic anhydride, chloromaleic anhydride, citraconic anhydride, butenyl succinic anhydride,
Examples include tetrahydrophthalic anhydride, and a particularly preferred unsaturated acid anhydride is maleic anhydride. These can be used alone or in combination of two or more. The proportion used is 0.001 parts by weight to 5 parts by weight, preferably 0.005 parts by weight to 4 parts by weight. If it is less than 0.001 part by weight or more than 5 parts by weight, the effect of improving impact resistance and heat resistance will not be sufficient, which is not preferable.

The styrenic polymer in the present invention has an MFR value of 0.5 to
40g/10min is preferable. Particularly preferred is a range of 0.7 to 35 g/10 min. If the MFR value is less than 0.5 g/10 min, the impact resistance will be improved but the appearance will be poor; if it exceeds 40 g/10 min, the heat resistance will be poor and the effect of improving the impact resistance will be small.

In the present invention, the MFR value is defined as the extruded sample that was extruded within the specified time using an apparatus specified in 8STM 0-1238 at a load of 10 hours and a temperature of 220°C, and then weighed for 10 minutes. The unit is (g/10min), which is a value converted to the flow weight.

The resin composition of the present invention may include glass fibers, carbon fibers, aramid fibers, silicon carbide fibers, potassium titanate fibers, boron nitride fibers, depending on the use and purpose, within a range that does not adversely affect the original physical properties of the resin. Or other organic fibers, inorganic fibers, metal fibers, calcium carbonate, talc, mica, inorganic silicates, silica gel, hydrotalcite,
One or more reinforcing fillers such as cristobalite and clay may be added. Further, one or more types of various additives such as flame retardants, heat stabilizers, antioxidants, waxing agents, lubricants, and colorants can be added.

As a compounding method for obtaining the resin composition according to the present invention, a mixture of a predetermined amount of nylon 46 resin, a butadiene rubber-modified styrene copolymer, and an acid anhydride group-containing unsaturated compound is directly mixed into a phonbar. Nylon 46 resin, butadiene-based rubber-modified styrenic copolymer, and acid anhydride group-containing unsaturated compound are mixed by injection molding or using a measuring device such as a screw feeder, table feeder, or belt feeder. Each is melt-kneaded using a single-screw or multi-sleeved extruder without being weighed, extruded as a sliver, and made into pellets using a cutter. It can be done by method.

The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited thereto.

(Example) Physical property measurements described in Examples and Comparative Examples were performed according to the following method.

Roughness, bubbles, color, etc. on the surface of the molded product were observed. The results are shown with the following symbols.

O: Good Δ: Fairly bad ×: Bad Izod day! 'Inspection? 23”C, thickness 178 per ASTM D-256
Measured in inches with a notch.

The flexural modulus was measured according to ASTM D-790.

Under heavy load (18.6 hours) according to ASTM D-648
/cffl).

Immersed in water with a water absorption rate of 23°C, it is flat! The water absorption rate was measured when the temperature reached -.

Using an apparatus specified in ASTM D-1238, a sample extruded within the specified time at a load of 10 kg and a temperature of 220°C was cut out, and its weight was weighed and converted to the flow weight for 10 minutes. The value was used.

Examples 1 to 4 Nylon 46 resin (Unitika Nylon 46.F5000) as component (A) having a relative viscosity of 4.0 in Ig/dβ in 30″C 196% sulfuric acid, and M as component (B)
A butadiene-based rubber-modified styrenic polymer with an FR value of 0.7.10.2L 33g/10min and maleic anhydride as component (C) were blended at the compounding ratio shown in Table 1, and then processed in a twin-screw extruder. (at 300° C.), extrusion, and cutting to obtain pellets. I got it
/ foot too'c for 15 hours, and various test pieces were obtained using the usual injection molding method, and the heat distortion temperature, rigidity, Izot impact strength, water absorption rate, and appearance of the molded products were evaluated. The results are shown in Table 1.

Comparative Example 1 The above nylon 46 resin and MFR value are Log/10min
The butadiene-based rubber-modified styrenic polymer was evaluated by the method shown in the Examples. The results are shown in Table 1.

Comparative Examples 2 to 3 The above nylon 46 resin and MFR value are 0.4.48 g/1
The butadiene-based rubber-modified styrenic polymer and maleic anhydride were evaluated by the method shown in Examples. The results are shown in Table 1.

By improving impact resistance and water resistance while maintaining excellent thermal and mechanical properties, it is possible to obtain a resin composition with well-balanced physical properties and excellent appearance of molded products, which can be applied to a wide range of fields. It is.

Claims (2)

[Claims] (1) (A) 40 to 95% by weight of nylon 46 resin, (
B) Styrenic polymer 6 obtained by polymerizing an aromatic vinyl compound and a vinyl cyanide compound in the presence of a rubbery polymer
(C
) A resin composition containing 0.001 to 5 parts by weight of an acid anhydride group-containing unsaturated compound. (2) (B) The resin according to claim 1, wherein the styrenic polymer obtained by polymerizing an aromatic vinyl compound and a vinyl cyanide compound in the presence of a rubbery polymer has an MFR value of 0.5 to 40 g/10 min. Composition.