JP2657992B2 - Dispersant for incompatible synthetic resin - Google Patents

Description

The present invention relates to a dispersant for an incompatible synthetic resin. 2. Description of the Related Art Various types of molded articles are widely manufactured using two or more types of synthetic resins that are mutually incompatible. In this case, it is necessary to melt and knead at least two mutually incompatible synthetic resins as uniformly as possible. For this purpose, a dispersant for compatibilizing the two or more synthetic resins is used. Due to its properties, the dispersing agent used here is required to be one that sufficiently compatibilizes the synthetic resin as a raw material without deteriorating the properties of the synthetic resin. The present invention relates to a dispersant that meets such a demand.

<Prior art and its problems> Conventionally, various polymer compounds have been used as dispersants for synthetic resins. However, these polymer compounds are generally difficult to dissolve in a solvent, and when they are used as a dispersant for an incompatible synthetic resin, the effect as a dispersant is extremely low.

Recently, it has been studied to use a grit copolymer using a relatively high-molecular-weight monomer (hereinafter, referred to as a macromonomer) as a raw material as a dispersant for a synthetic resin. This graft copolymer is obtained by synthesizing a macromonomer having a controlled molecular weight and structure in advance, and copolymerizing the macromonomer with another vinyl monomer to incorporate the macromonomer into a polymer chain. As a graft copolymer using such a macromonomer, one having a polyester chain at a branch portion has been proposed (JP-B-54-44024, JP-B-60-99158). These graft copolymers are obtained by first obtaining a polyester chain corresponding to a branch portion by polycondensation of a dibasic acid and glycol, ring-opening polymerization of polycaprolactone, or ring-opening polymerization of acid anhydride and alkylene oxide. Then, since the two terminal groups of these polyester chains are both hydroxyl groups or carboxylic acid groups, various reactive agents are allowed to react with one of these terminal groups to introduce a vinyl group, thereby obtaining a macromonomer. Is synthesized, and the macromonomer is copolymerized with another vinyl monomer.

However, such conventional graft copolymers have the following problems. 1) Since a macromonomer whose terminal group is a hydroxyl group or a carboxylic acid group is used, a gel having an unknown structure is easily generated, and it is difficult to regulate the structure. 2) When synthesizing a macromonomer, by-products of a bifunctional macromonomer having vinyl groups introduced at both ends are unavoidable, and it is extremely difficult to remove these bifunctional macromonomers by purification. Eventually, the bifunctional macromonomer is involved in the copolymerization reaction. As a result, the three-dimensional gel is remarkably purified and mixed.

The graft copolymer having the above problems has various disadvantages when it is used as a dispersant for an incompatible synthetic resin. That is, the conventional graft copolymer cannot obtain good dispersibility in an incompatible synthetic resin, and in particular, melt-kneads the graft copolymer into a condensation synthetic resin such as a polyester resin, a polycarbonate resin, and a polyamide resin. Then, due to the action of the terminal groups such as the hydroxyl group and the carboxylic acid group, coloring of the synthetic resin and a decrease in the viscosity occur, which obviously deteriorates the synthetic resin as a raw material.

<Problems to be Solved by the Invention, Means for Solving the Problems> The present invention is to provide a new dispersant for incompatible synthetic resins which solves the above-mentioned conventional problems.

In view of the above circumstances, the present inventors have found that heat resistance is good, has good dispersibility in incompatible synthetic resins, and is melt-kneaded with resins such as polyester resins, polyamide resins, and polycarbonate resins. As a result of intensive studies to obtain a dispersant that does not cause the degradation of these resins even when the resin is used, it has been found that the grafted copolymer having a structure having a polycaprolactone chain blocked with a non-reactive end group at the branch portion is not required. It has been found that providing the polymer is correct and preferred.

That is, the present invention is a dispersant for compatibilizing mutually incompatible synthetic resins, and is composed of a structural unit I and a structural unit II represented by the following formulas, respectively. % By weight, and constituent unit II accounts for 20 to
The present invention relates to a dispersant for an incompatible synthetic resin, comprising a graft copolymer having a weight of 80% by weight and a molecular weight of 10,000 to 150,000.

[However, R ¹ , R ³ ; H or CH ₃ R ² ; an aliphatic or alicyclic hydrocarbon group having 1 to 18 carbon atoms or C _m H _2m O) _r R ⁵ Rwhere, R ⁵ ; 1 to 18 hydrocarbon groups, m; 2 or 3,
r; 1-5 R ⁴ ; CH ₃ or C ₂ H ₅ n; 6-90] In the graft copolymer used in the present invention, the raw material of the structural unit I is vinyl represented by the following general formula A: It is a polymerizable polycaprolactone derivative (hereinafter, referred to as macromonomer A).

[However, R ¹ , R ² , and n are the same as those in the above-mentioned structural unit I] The macromonomer A is a ring-opening addition reaction between a monohydric alcohol and ε-caprolactone, and is followed by an α, β-unsaturated monoester. It is obtained by an esterification reaction or a transesterification reaction using a carboxylic acid or an ester-forming derivative thereof. The ring-opening addition reaction between a monohydric alcohol and ε-caprolactone can be performed in the presence of a catalyst such as tetrabutoxytitanate or dibutyltin dilaurate.

Specific examples of the above monohydric alcohol include the following.

1) linear aliphatic alcohols; methanol, ethanol,
n) Butanol, n-octanol, octadecyl alcohol, etc. 2) Branched aliphatic alcohols; isopropanol, 2-ethylhexanol, isotridecyl alcohol, etc. 3) Other aliphatic or alicyclic alcohols; benzyl alcohol, cyclohexanol, etc. 4) Alkylene oxide adducts of alcohols of the above 1) to 3); methyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, etc. 5) Alkylene oxide adduct of phenol or phenol substituted with a hydrocarbon group; ethylene glycol Monophenyl ether, diethylene glycol monophenyl ether, polyoxyethylene (5 mol) nonyl phenyl ether, ethoxylated p-phenylphenol, ethoxylated 3,5-dibutylphenol, etc. is there.

In the alkylene oxide adducts of 4) and 5), examples of the alkylene oxide include ethylene oxide and propylene oxide, and the number of moles of the alkylene oxide added is 1 to 5 mol.

Specific examples of the α, β-unsaturated monocarboxylic acids or their ester-forming derivatives include acrylic acid, methacrylic acid, acrylic acid chloride, methacrylic acid chloride, methyl acrylate, methyl methacrylate and the like. Can be

The esterification reaction or transesterification reaction using these can be carried out in the presence of a radical polymerization inhibitor and an acidic catalyst such as sulfuric acid or p-toluenesulfonic acid.

The preferred molecular weight range of the macromonomer A thus obtained is 800 to 10,000, and the more preferred molecular weight range is
1000 to 8000.

Constituent unit II in the graft copolymer used in the present invention
Is a vinyl monomer represented by the following general formula B (hereinafter referred to as vinyl monomer B).

[However, R ³ and R ⁴ are the same as in the case of the structural unit II] Specific examples of the vinyl monomer B include methyl methacrylate, methyl acrylate, ethyl methacrylate, and ethyl acrylate. One or more of these can be used.

The ratio of each structural unit forming the graft copolymer used in the present invention is in the range of structural unit I / structural unit II = 80/20 to 20/80 (% by weight), and preferably 70/30 to 30 / 70 (% by weight). If the ratio is outside the above range, the performance exhibited by the graft copolymer, for example, the expression of dispersibility becomes insufficient.

The graft copolymer used in the present invention is synthesized using the macromonomer A and the vinyl monomer B as described above. In this synthesis, ordinary methods such as solution polymerization, emulsion polymerization and suspension polymerization can be applied. The molecular weight of the graft copolymer to be synthesized is in the range of 10,000 to 150,000.

The graft copolymer used in the present invention is extremely useful as a dispersant for an incompatible synthetic resin. More specifically,
When melt-kneading two or more types of synthetic resins that are mutually incompatible, a stable polymer blend can be formed,
In this case, the synthetic resin does not deteriorate.

Hereinafter, the configuration and effects of the present invention will be more specifically described with reference to examples and the like, but the present invention is not limited to the examples.

<Examples and the like> Test Category 1 (Synthesis of Graft Copolymer as Dispersant for Incompatible Synthetic Resin) Graft copolymers of Examples and Comparative Examples exemplified below were synthesized, and their contents were described. The results are summarized in Tables 1 and 2.

Example 1 Synthesis of Macromonomer A-1 50 g of ethyl cellosolve and 1 g of tetrabutyl titanate
Was charged into a flask, the inside of which was replaced with nitrogen, and then heated to 150 ° C. After dropping 2200 g of ε-caprolactone over 1 hour, the reaction was continued at 150 ° C. for 2 hours to obtain a caprolactone adduct (hydroxyl value 14.4).

Next, 250 g of the caprolactone adduct obtained above, 8.0 g of methacrylic acid, 250 g of toluene, 0.5 g of sulfuric acid and 0.1 g of hydroquinone were charged into a flask, and heated under reflux for 8 hours to carry out an esterification reaction. Then, after cooling the content to 60 ° C., the sulfuric acid was neutralized with sodium hydrogen carbonate, and the salt generated by the neutralization was dissolved by adding water. Separate the aqueous layer and the toluene layer, dehydrate the toluene layer under reduced pressure,
The solvent was removed to obtain a macromonomer A-1 (acid value: 0.4, hydroxyl value: 1.1, molecular weight: 3970) (the molecular weight is the value in terms of polystyrene by the GPC method, the same applies hereinafter).

Synthesis of Graft Copolymer P-1 30 g of the above-mentioned macromonomer A-1, 30 g of methyl methacrylate and 90 g of toluene were charged into a flask, the inside of which was replaced with nitrogen, and then heated. When the internal temperature reaches 70 ° C, a 10% toluene solution of azobisisobutyronitrile 10
ml was gradually added and the reaction was carried out for 2 hours. Next, the reaction solution was cooled to room temperature, and poured into 500 ml of methanol to precipitate a copolymer. The precipitated white precipitate was washed three times with 100 ml of methanol, and then dried under vacuum at 70 ° C.
A graft copolymer P-1 was synthesized. The graft copolymer P-1 was composed of methyl methacrylate corresponding to the vinyl monomer B as a raw material, the content of the structural unit II was 43% by weight, and the molecular weight was 23.
000.

Example 2 Synthesis of Macromonomer A-2 By the same operation as in Example 1, n-octanol 13
205 g of ε-caprolactone was reacted with 0 g to obtain a caprolactone adduct (hydroxyl value 26.1). Next, the caprolactone adduct was reacted with methacrylic acid to obtain a macromonomer A-2 (acid value 0.6, hydroxyl value 1.0, molecular weight 2220).

..Synthesis of graft copolymer P-2 By the same operation as in Example 1, macromonomer A-
2 and 30 g of methyl methacrylate were reacted to synthesize a graft copolymer P-2. Graft copolymer P
-2 is a content of 48% by weight of the structural unit II using methyl methacrylate corresponding to the vinyl monomer B as a raw material, and a molecular weight of 4500.
It was 0.

Example 3 Synthesis of Macromonomer A-3 Phenylcarbitol was prepared in the same manner as in Example 1.
20 g of ε-caprolactone was reacted with 46 g to obtain a caprolactone adduct (hydroxyl value 8.9). Next, the caprolactone adduct was reacted with methacrylic acid to obtain a macromonomer A-3 (acid value 0.3, hydroxyl value 0.7, molecular weight 6400).

..Synthesis of graft copolymer P-3 By the same operation as in Example 1, macromonomer A-
3 and 30 g of methyl methacrylate were reacted to synthesize a graft copolymer P-3. Graft copolymer P
-3 is a content of 44% by weight of the structural unit II using methyl methacrylate corresponding to the vinyl monomer B as a raw material, and a molecular weight of 2900.
It was 0.

Example 4 Synthesis of Macromonomer A-4 In the same manner as in Example 1, ε-caprolactone 1 was added to 90 g of a phenol ethylene oxide (4 mol) adduct.
After reacting 330 g, a caprolactone adduct (having a hydroxyl value of 13.
3) got. Then, the caprolactone adduct was reacted with methacrylic acid to give a macromonomer A-4 (acid value of 0.1.
5, hydroxyl value 0.6, molecular weight 4300).

..Synthesis of graft copolymer P-4 By the same operation as in Example 1, macromonomer A-
4 and 30 g of methyl methacrylate were reacted to synthesize a graft copolymer P-4. Graft copolymer P-
No. 4 is a 45% by weight content of the structural unit II using methyl methacrylate corresponding to the vinyl monomer B as a raw material, and a molecular weight of 40,000.
Met.

Comparative Example 1 Synthesis of Graft Copolymer R-1 By the same operation as in Example 1, macromonomer A-
9g and 1 g of methyl methacrylate were reacted to synthesize a graft copolymer R-1. Graft copolymer R
-1 represents a content of 84% by weight of the structural unit II made from methyl methacrylate corresponding to the vinyl monomer B, and a molecular weight of 3300.
It was 0.

Comparative Example 2 Synthesis of Macromonomer C-1 Ethyl cellosolve 90 was obtained in the same manner as in Example 1.
g was reacted with 342 g of ε-caprolactone to obtain a caprolactone adduct (hydroxyl value 131). Next, the caprolactone adduct was reacted with methacrylic acid to obtain a macromonomer C-1. Macromonomer C-1 has a molecular weight of 50
0, the average number of moles of ε-caprolactone added was 3.

..Synthesis of graft copolymer R-2 By the same operation as in Example 1, macromonomer C-
1 and 30 g of methyl methacrylate were reacted to synthesize a graft copolymer R-2. Graft copolymer R
-2 represents a content of 47% by weight of the structural unit II using methyl methacrylate corresponding to the vinyl monomer B as a raw material, and a molecular weight of 1800.
It was 0.

Comparative Example 3 Synthesis of Macromonomer C-2 25 g of hydroxyethyl methacrylate, 1 g of tetrabutyl titanate and 0.2 g of hydroquinone were charged into a flask, the inside of which was replaced with nitrogen, and then heated to 150 ° C. Then, after 750 g of ε-caprolactone was added dropwise over 1 hour, the reaction was continued at 150 ° C. for 2 hours, and the macromonomer C-
2 (hydroxyl value 15.2, molecular weight 3700) was obtained.

Synthesis of Graft Copolymer R-3 In the same manner as in Example 1, 90 g of toluene was used as a solvent, and 30 g of macromonomer C-2 and 30 g of methyl methacrylate were reacted. At the end of the reaction, the formation of a gel was observed. Cool the reaction solution to room temperature,
This was poured into 500 ml of methanol to precipitate a copolymer. The precipitated white precipitate was washed three times with 100 ml of methanol, and then dried under vacuum at 70 ° C. to synthesize a graft copolymer R-3. The graft copolymer R-3 swelled in toluene, but was insoluble, so that its molecular weight could not be measured.

Comparative Example 4 Synthesis of Graft Copolymer R-4 By the same operation as in Example 1, macromonomer A-
1 and 51 g of methyl methacrylate were reacted to synthesize a graft copolymer R-4. Graft copolymer R
-4 is a content of the structural unit II of 16% by weight and a molecular weight of 4900, which is obtained from methyl methacrylate corresponding to the vinyl monomer B.
It was 0.

Comparative Example 5 Synthesis of Macromonomer C-3 148 g of phthalic anhydride, 100 g of succinic anhydride and 130 g of ethylene glycol were charged into a flask and reacted at 150 ° C. for 2 hours. Then, the reaction product was heated to 200 ° C. to carry out condensation to obtain a polyester (acid value 17, hydroxyl value 20).

Next, the polyester was cooled to 160 ° C., and 8 g of maleic anhydride was added thereto and reacted for 1 hour to obtain a macromonomer C-3 having a carboxyl group at both terminals (acid value: 36, average molecular weight: about 3030). Obtained.

..Synthesis of graft copolymer R-5 100 g of the above macromonomer C-3 and 70 g of styrene
And 300 g of xylene were charged into a flask and dissolved.
This was heated to 80 ° C., 1 g of benzoyl peroxide was added while introducing nitrogen, and the reaction was continued for 6 hours. Then, the same operation as in Example 1 was performed on the contents to synthesize a graft copolymer R-5. Graft copolymer R
In the case of -5, when this was dissolved in toluene, insolubles were partially observed, and thus the molecular weight was not measured.

In Table 1, n in the general formula A is the average number of moles added.

The macromonomers C-1 to C-3 do not correspond to the structural unit I.

 Styrene does not correspond to vinyl monomer B.

The molecular weight of the graft copolymers R-3 and R-5 could not be measured.

Test Category 2 (Evaluation of synthesized graft copolymer as dispersant for incompatible synthetic resin) 100 g of polycarbonate for injection molding, 30 g of nylon-6 for injection molding, and graft of each Example or each Comparative Example 3 g of the copolymer was charged into a small experimental kneader, and 25
Kneaded at 0 ° C. for 4 minutes. Next, a sheet having a thickness of 2 mm was formed using a hot press machine. At the same time, the same operation was performed for the one without the addition of the graft copolymer,
A sheet was formed (blank). Then, the sheet properties and the dispersion state were evaluated as follows, and the results are shown in Table 3.

Evaluation of sheet properties The presence or absence of holes in the sheet and the degree of coloring of the sheet were visually observed. Also, by folding the sheet with both hands,
The degree of difficulty of breaking was examined, and the strength was evaluated.

Evaluation of dispersion state The sheet was immersed in chloroform at room temperature for 5 minutes to etch the surface. The surface state of the sheet after the etching treatment is observed by a scanning electron microscope,
The homogeneity of the dispersed state and the shape and particle size of the dispersed particles were examined. In this case, the homogeneity was evaluated as follows.
That is, the dispersion state is greatly improved over the blank,
A sample having a fine spherical shape and homogeneously dispersed was evaluated as good, and a sample having no difference from the blank was evaluated as defective.

<Effects of the Invention> As is clear from the results of the respective tables, the present invention described above has good heat resistance and is not compatible with each other without causing deterioration of the synthetic resin as a raw material. When two or more kinds of synthetic resins are melt-kneaded, there is an effect that excellent dispersion performance is exhibited for these synthetic resins.

Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication (C08L 101/00 55:00)

Claims (4)

(57) [Claims] 1. A dispersing agent for compatibilizing mutually incompatible synthetic resins, comprising a structural unit I and a structural unit II represented by the following formula, respectively, wherein the structural unit I is 80 to
20% by weight, and constituent unit II is 20-80% by weight of the whole
A dispersant for an incompatible synthetic resin, comprising a graft copolymer having a molecular weight of 10,000 to 150,000. [However, R ¹ , R ³ ; H or CH ₃ R ² ; an aliphatic or alicyclic hydrocarbon group having 1 to 18 carbon atoms or C _m H _2m R) _r R ⁵ Rwhere, R ⁵ ; 1 to 18 hydrocarbon groups, m; 2 or 3,
r; 1 to 5｝ R ⁴ ; CH ₃ or C ₂ H ₅ n; 6 to 90] 2. The structural unit I is: The dispersant for an incompatible synthetic resin according to claim 1, comprising a graft copolymer wherein 3. The structural unit II is: 3. The graft copolymer according to claim 1, wherein the graft copolymer is
The dispersant for an incompatible synthetic resin according to the above. 4. The dispersant according to claim 1, wherein the mutually incompatible synthetic resins are polycarbonate and nylon.