JPH0455413A - Surface modifier for crystalline resin - Google Patents

Abstract

PURPOSE:To obtain a surface modifier providing a crystalline resin with surface glass and beautiful appearance, comprising a maleimide-based copolymer containing a maleimide derivative, an aromatic vinyl compound and a vinyl- based monomer copolymerizable with said derivative and said compound, and having a specific molecular weight. CONSTITUTION:The objective modifier comprising a maleimide-based copolymer containing (A) 1-99 wt.% maleimide derivative (e.g. maleimide or N- methylmaleimide), (B) 1-99 wt.% aromatic vinyl compound (e.g. styrene or vinylnaphthalene) and (C) <=50 wt.%, perferably 1-30 wt.% vinyl-based monomer [e.g. acrylonitrile or methyl (meth)acrylate]copolymerizable with the derivative (A) and the compound (B), and having 1,000-500,000 weight-average molecular weight.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a surface modifier that improves the surface gloss and appearance of crystalline resins.

[Prior Art] Crystalline resins have various excellent physical properties, chemical properties, mechanical properties, and moldability, and are widely used in numerous industrial fields. Plastic resins are used with the addition of different base materials such as various metals, inorganic materials such as glass, or polar polymer materials in order to improve their heat distortion temperature, or because they have poor adhesion with these various base materials. The disadvantage is that it is difficult to combine.

As a method to improve this drawback, for example, a method is known in which polypropylene is graft-modified with an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride such as acrylic acid or maleic acid, thereby introducing a polar group and imparting adhesive properties. ing.

[Problems to be Solved by the Invention] However, even when modified polypropylene modified with an unsaturated carboxylic acid anhydride as described above is added to a system of polypropylene and glass fiber, adhesion is still insufficient.
Glass fibers are raised on the surface of the molded product, resulting in poor surface gloss and poor appearance, which poses a problem when performing secondary processing such as painting.

Such a phenomenon is observed not only in polypropylene but also in polyesters and polyamides having polar groups such as ester groups and amide groups.

[Means for Solving the Problems] The present inventors have completed the present invention as a result of their earnest efforts to solve the above problems.

That is, the present invention comprises 1 to 99% by weight of the maleimide derivative (a), 1 to 99% by weight of the aromatic vinyl compound (b), and at least one vinyl compound copolymerizable with (a) and (b). The present invention provides a surface modifier for crystalline resins comprising a maleimide copolymer containing 50% by weight or less of monomer (c) and having a weight average molecular weight of 1,000 to 500,000.

Maleimide derivative (a) is represented by formula (1).

(In the formula, R,, R2 each represent hydrogen, halogen, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or aryl group, and R3 is hydrogen, substituted or unsubstituted alkyl group having 1 to 2 Q carbon atoms. represents a group or an aryl group.

Specific examples include maleimide, N-methylmaleimide,
N-ethylmaleimide, N-isopropylmaleimide,
N-t-butylmaleimide, N-phenylmaleimide,
α-Methyl-N-phenylmaleimide, N-0-methylphenylmaleimide, N-m-methylphenylmaleimide, N-p-methylphenylmaleimide, N-cyclohexylmaleimide, N-o-hydroxyphenylmaleimide, N- m-hydroxyphenylmaleimide, N-p
-Hydroxyphenylmaleimide, N-o-methoxyphenylmaleimide, N-m-methoxyphenylmaleimide, N-p-methoxyphenylmaleimide, N-o-chlorophenylmaleimide, N-m-chlorophenylmaleimide, N-p-chlorophenylmaleimide, N-o-
Examples include carboxyphenylmaleimide, Nm-carboxyphenylmaleimide, Np-carboxyphenylmaleimide, N-dichlorophenylmaleimide, and N-naphthylmaleimide. These can be used alone or in combination of two or more.

Examples of aromatic vinyl compounds (b) include styrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene, chlorstyrene, dichlorostyrene, bromostyrene, dipromostyrene, α-methylstyrene,
Examples include α-ethylstyrene, nuclear alkyl-substituted α-methylstyrene, nuclear halogen-substituted α-methylstyrene, vinylnaphthalene, and the like.

Vinyl monomers (c) copolymerizable with (a) and (b) include unsaturated nitrile compounds, α,β-unsaturated carboxylic acid alkyl ester compounds, maleic anhydride, itaconic anhydride, and citraconic anhydride. .

Examples include unsaturated acids such as acrylic acid and methacrylic acid, and vinyl acetate.

Examples of the unsaturated nitrile compound include acrylonitrile and methacrylonitrile.

As the α,β-unsaturated carboxylic acid alkyl ester compound, for example, acrylic acid methyl ester.

Acrylic acid esters such as acrylic acid ethyl ester and acrylic acid butyl ester, methacrylic acid methyl ester, and methacrylic acid ethyl ester.

Examples include methacrylic esters such as lauryl methacrylate and stearyl methacrylate.

Methods such as solution polymerization, suspension polymerization, and emulsion polymerization can be used to produce the maleimide copolymer resin in the present invention. The solution polymerization method is illustrated here. While the aromatic vinyl compound (b) and the vinyl monomer (c) are being stirred in an organic solvent at a temperature of 0°C to 150°C in the presence of a radical initiator, maleimide is formed over several tens of minutes to several hours. It can be produced by adding the derivative (a) dropwise and further reacting for several minutes to several hours.

The concentration of the reaction system is generally selected in the range of 50 to 500 g/g.

The initiator concentration is generally between 1000 and
A range of 1100000 pp is selected.

As the organic solvent, various solvents can be used, such as dimethylformamide, dimethylsulfoxide, tetrahydrofuran, toluene, 1,4-dioxane, p-ethylphenol, and the like.

The radical initiator is not particularly limited as long as it is used as an initiator for normal radical polymerization, and examples include azobisisobutyronitrile, azobisisovaleronitrile, benzoyl peroxide, and -butyl hydroperoxide. can be mentioned.

The surface modifier according to the present invention contains 1 to 99% by weight of the maleimide derivative (a) and 1 to 99% by weight of the aromatic vinyl compound (b).
% by weight, and at least 50% by weight of at least one vinyl monomer (c) copolymerizable with (a) and (b).

If the content (a) of the maleimide derivative is less than 1% by weight, the heat resistance and effectiveness of the modifier will be low, and if it exceeds 99% by weight, the resin will become brittle. Furthermore, if the content of the aromatic vinyl compound (b) is less than 1% by weight, the molecular weight of the resin will be small, and the modifier will be easily decomposed.

Furthermore, the content of at least one vinyl monomer (c) copolymerizable with (a) and (b) is 50% by weight or less, preferably 1
-30% by weight, and if it exceeds 50% by weight, the effect of the modifier will decrease, which is not preferable.

Furthermore, the weight average molecular weight of the surface modifier according to the present invention is 1
000 to 500000 is an essential requirement.

If the weight average molecular weight is less than 1000, the modifier decomposes and crystals <
, and when it exceeds 500,000, the dispersion state of the resin deteriorates.

The amount of the surface modifier according to the present invention added is 1 to 50 parts by weight, more preferably 1 part by weight, per 100 parts by weight of the total of different base materials such as crystalline resins, inorganic materials such as glass, and polar polymer materials.
~30 parts by weight. Less than 1 part by weight has little effect;
Further, even if the amount exceeds 50 parts by weight, no improvement in the effect is observed.

Crystalline resins to which the surface modifier according to the present invention can be applied include polyolefins such as polypropylene and polyethylene, and polyethylene terephthalate.

Polyesters such as polybutylene terephthalate, nylon 6, nylon 66, nylon 11. nylon 610
．． Nylon 12. Examples include polyamides such as nylon 46, polyoxymethylene, polyphenylene sulfide, and the like.

Examples of different substrates such as inorganic materials such as glass and polar polymer materials to which the surface modifier of the present invention can be applied include glass fibers, carbon fibers, ceramic fibers such as alumina fibers, aramid fibers, and wholly aromatic polyesters. Fibers, metal fibers, reinforcing fillers such as potassium titanate whiskers, calcium carbonate, mica, talc, silica, barium sulfate, calcium sulfate, kaolin, clay, pyroferrite, bentonite, sericite, zeolite, nephelinsinite, attapulgite, wollastonite, ferrite, calcium silicate, magnesium carbonate, dolomite,
Contains inorganic fillers such as antimony dioxide, zinc oxide, titanium oxide, magnesium oxide, iron oxide, molybdenum disulfide, graphite, gypsum, glass beads, glass powder, glass balloons, quartz, quartz glass, and organic and inorganic pigments. You can also do it.

For example, the glass fiber has a fiber length of 1.5 to 12 m.
Examples include chopped strands with a fiber diameter of 3 to 24 μm, milled fibers with a fiber diameter of 3 to 8 μm, and examples of glass flakes and glass powder include those with a mesh size of 325 mesh or less.

The method of blending the surface modifier according to the present invention is as follows: 1) A method of mixing each component in a mixer or the like and melting and kneading the mixture using an extruder to form pellets. 2) Pellets obtained by method 1) There is a method in which other components are added to the mixture and melt-kneaded again to form pellets. 3) A method in which each component is dissolved in a solvent and heated and stirred.

Further, in each of the above steps, it is also possible to use known equipment such as a Banbury, a 21-da, an autoclave, etc., singly or in combination.

The resin composition using the surface modifier according to the present invention can be processed into various molded products using methods such as injection molding, sheet molding, vacuum molding, irregular molding, and foam molding.

In addition, plasticizers and mold release agents such as aromatic hydroxy derivatives, silane-based and titanate-based coupling agents, commonly used known antioxidants, ultraviolet absorbers, antistatic agents, blowing agents, heat stabilizers, A fluorescent agent, a lubricant, a weathering stabilizer, a crystal nucleating agent, a foaming agent, a rust preventive agent, an ion trapping agent, a flame retardant, a flame retardant aid, etc. may be added as necessary.

[Function] The surface modifier for crystalline resin according to the present invention has good adhesion to inorganic materials such as glass, and the surface gloss and appearance of crystalline resin molded products to which it is added are significantly improved, making it difficult to paint. ,
It can be used for materials that require surface modification secondary processing such as plating and vapor deposition.

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

Examples 1-10. Comparative Examples 1 to 3 Maleimide copolymer resins (MI-1) to (Ml-5) having the compositions shown in Table 1 were produced by the following method.

(Ml-1) Styrene 100 was placed in a 5000 mj7 4-tube flask equipped with a stirrer, thermometer, nitrogen inlet tube, and condenser.
g (0,96 mo 1) and 70 g of methyl methacrylate
(0.7 mol) and 1,4-dioxane 100100
Add O and stir to dissolve. After raising the temperature to 70°C, add 4.8 g (30 mmol) of azobisisobutyronitrile, and then add N-(p-carboxyphenyl) dissolved in 1,500 mg of 1,4-dioxane. ) Maleimide 135g
(0.62 mol) solution was added dropwise over 4 hours.

After the dropwise addition, the mixture was stirred for 20 hours, cooled to room temperature, and poured into a large amount of methanol to precipitate the polymer, which was then filtered. The polymer was then purified by dissolving it in 1,4-dioxane and reprecipitation in methanol, and vacuum drying at 120°C for 24 hours to obtain 230g of white powder of N-(p-carboxyphenyl)maleimide copolymer (yield: 75%). %) was obtained.

The weight average molecular weight of the obtained polymer was determined by gel permeation chromatography (GPC) Tosoh Corporation.
It was calculated using HLC-802A (manufactured by HLC-802A) and THF as a solvent in terms of polystyrene.

In a similar manner, N-phenylmaleimide copolymer (MI
-2) to (Ml-5) were prepared.

Maleimide copolymer resin (Ml-
1) ~ (M I-5) and polypropylene resin (Tosoh Corp. manufactured by Bunsaw Polypro J 5100A MF R1
1), acid-modified polypropylene resin (manufactured by Tosoh Corporation, 2% maleic anhydride-modified polypropylene), polyamide (
Nylon 6, nylon 66 (manufactured by Ube Industries, Ltd.), polyester (polyethylene terephthalate, polybutylene terephthalate, manufactured by Mitsubishi Rayon Co., Ltd.), and glass fiber (
C, F) (chopped strands with a fiber diameter of 13 μm) were mixed at the blending ratio shown in Table 2 to obtain a molded product.

The gloss (J Is K7105) of this molded article was measured, and the appearance was evaluated by the amount of GF embossed on the surface. Furthermore, the Rp value (difference from average height to maximum height) shown in FIG. 1 was measured and evaluated using a surface roughness meter. Rp value is 2
Preferably less than μm.

The results of these measurements are shown in Table 3.

Furthermore, when the fractured surface of the molded product was observed using a GF back surface scanning electron microscope, it was found that the system to which the modifier of the present invention was added was GF.
Adhesion of resin on the back surface was observed, but no adhesion was observed in the non-additive system.

This suggests that the use of the surface modifier for crystalline resins according to the present invention provides good adhesion to inorganic materials.

[Effects of the Invention] As detailed above, the surface modifier for crystalline resin according to the present invention has good adhesion to inorganic materials such as glass, and crystalline resin molded products to which it is added have surface gloss, Since the appearance is significantly improved, it can be used as a material that requires surface modification secondary processing such as painting and plating vapor deposition, and its industrial value is high.

Table 3 4,

[Brief explanation of drawings]

FIG. 1 explains the Rp value indicating the surface roughness of a molded product. The wavy pattern shown in the figure indicates the surface condition of the molded product.

Claims (1)

[Claims] (1) 1 to 99% by weight of the maleimide derivative (a), 1 to 99% by weight of the aromatic vinyl compound (b), and (a),
Contains 50% by weight or less of at least one vinyl monomer (c) copolymerizable with (b), and has a weight average molecular weight of 100%.
A surface modifier for crystalline resins comprising a maleimide copolymer having a molecular weight of 0 to 500,000.