JPS6323224B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a molding composition that has improved molding process operability and quality, and more specifically, suppresses the occurrence of deposits on molds in injection molding and rolls in extrusion molding, and improves the appearance. The present invention relates to a thermoplastic resin composition that has good properties and excellent reproducibility of patterns on molds and rolls.

Rubber-reinforced resins have a good balance of properties such as impact resistance, rigidity, heat resistance, and chemical resistance, and these excellent properties are used in a variety of applications such as vehicles, electricity, equipment, and miscellaneous goods. . Most of them are processed by thermoforming and put into practical use, but injection molded products often have uneven gloss or the reproducibility of the fine patterns of the mold is lost in a short period of time. be. As a countermeasure, wiping and cleaning of the deposits on the molds is performed, but this requires manpower and time, which causes problems such as decreased molding productivity and the occurrence of defective products due to patterns being worn away. It is becoming. In addition, in extrusion molding, the gloss of the surface of the molded product may decrease over time, uneven gloss may occur, or the reproducibility of patterns in molding to provide decorative surfaces such as skin wrinkles and satin finish may decrease. The commercial value of things decreases. In order to avoid this, it is necessary to wipe off the deposits on the roll, but this requires a great deal of effort. Although it is possible to avoid defects in molded products caused by deposits during thermoforming by selecting molding conditions, it is practically difficult to do so, and it is strongly recommended that this improvement be achieved by improving the resin composition. It was wanted.

The present inventors investigated improvements in the molding processability and quality of the rubber-reinforced resin from the viewpoint of suppressing deposits, and found that it is extremely effective to add a compound having a glycidyl group to the resin. heading,
We have arrived at the present invention.

The present invention is a butadiene-based rubber graft polymer resin.
For 100 parts by weight (hereinafter, parts by weight are abbreviated as parts),
0.01-5 parts of phenolic antioxidant and 0.05-5 parts of glycidyl ether and/or glycidyl ester
10 parts of the molding process, which is characterized by improved molding process operability and quality; that is, there is no need to remove deposits from molds or rolls, and there is no uneven gloss of the molded product. It is a thermoplastic resin composition with good gloss and pattern development during molding.

The butadiene-based rubber graft polymer resin, which is the first component of the present invention, can be produced by a polymerization method such as an emulsion graft polymerization method, an emulsion suspension polymerization method using a partial emulsion graft polymerization method, or an emulsion bulk polymerization method. A graft polymer resin obtained by graft polymerizing a produced butadiene-based rubbery polymer with an unsaturated nitrile such as acrylonitrile or methacrylonitrile, or an aromatic vinyl such as styrene or α-methylstyrene, and this graft polymer resin. and the copolymer of unsaturated nitrile and aromatic vinyl, or a blend of this graft polymer resin and the butadiene-based rubbery polymer. In the present invention, the butadiene-based rubbery polymer includes not only a butadiene homopolymer but also a copolymer containing butadiene as a main component with other monomers. Also included in the butadiene-based rubber graft polymer resin of the present invention are those obtained by replacing part or all of the unsaturated nitriles and aromatic vinyls with (meth)acrylates such as methyl methacrylate.

The phenolic antioxidant, which is the second component of the present invention, is an effective component mainly for preventing deterioration of rubbery polymers, for example, 2,6-di-t-butyl-
4-methylphenol, 2,2'-methylenebis(6-t-butyl-4-methylphenol), octadecyl-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate, etc. can be given. These phenolic antioxidants are used singly or as a mixture of two or more, and may be combined with thiodipropionates such as dilauryl-3,3'-thiodipropionate and distearyl-3,3'-thiodipropionate. It is also possible to use them together.

The amount of the phenolic antioxidant required is 0.01 to 5 parts per 100 parts of the butadiene rubber graft polymer resin. If it is less than 0.01 part, the antioxidant effect will be insufficient, resulting in noticeable discoloration during molding and fine roughness on the surface of the molded product.
If it exceeds 50%, the heat deformation temperature will drop and good performance will not be obtained. Other well-known antioxidants include organic phosphites and amine compounds, but the use of organic phosphites causes a significant decrease in impact strength, which is the primary characteristic of rubber-reinforced resins. Ru. In particular, when used in combination with a glycidyl compound as in the present invention, the impact strength decreases even more significantly, and the physical properties become unbalanced, making it difficult to obtain good quality. Furthermore, although amine compounds have excellent antioxidation properties, they undergo significant thermal changes, reduce their commercial value in terms of color appearance, and are not practical.

Glycidyl ether and/or glycidyl ester, which is the third component of the present invention, is mainly effective in suppressing deposits during molding, such as methyl glycidyl ether, butyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, butyl glycidyl ether, and butyl glycidyl ether. Monoglycidyl ethers such as phenyl glycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, glycerol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, 4,4'- Examples include polyglycidyl ethers such as isopropylidene diphenol diglycidyl ether, monoglycidyl esters such as acrylic acid glycidyl ester, oleic acid glycidyl ester, and polyglycidyl esters such as maleic acid diglycidyl ester and phthalic acid diglycidyl ester. They can be used singly or as a mixture of two or more. Here, epoxy compounds other than glycidyl that have a similar chemical structure to glycidyl compounds (e.g., epoxidized soybean oil,
(alpha-olefin oxide, poly-1,2-butadiene oxide, etc.), contrary to expectations, the effect of the present invention is not so good, or even if it is, it is very small and has no practical meaning.

The amount of the glycidyl compound to be blended is in the range of 0.05 to 10 parts, particularly preferably 0.5 to 5 parts, based on 100 parts of the butadiene rubber graft polymer resin. If the amount is less than 0.05 part, the effect of the present invention cannot be obtained, and if it exceeds 10 parts, the effect of the present invention reaches its limit and at the same time, impact strength, heat distortion temperature, etc. decrease, making it impossible to put it into practical use.

The method of adding these antioxidants and glycidyl compounds to the rubber reinforced resin is not particularly limited, and
In addition, lubricants, plasticizers, fillers, antistatic agents, light stabilizers, ultraviolet absorbers, colorants, foaming agents, etc. may be added as necessary.

Example 1 After adding 0.5 part of 4,4'-thiobis(6-t-butyl-3-methylphenol) to a latex obtained by emulsion graft polymerization of 15 parts of polybutadiene, 63 parts of styrene, and 22 parts of acrylonitrile. ,
It was coagulated with dilute sulfuric acid, and the coagulated product was washed with water until it became neutral, dehydrated, and dried to obtain a powdery polymer. 2 parts of glycidyl allyl ether and 1 part of ethylene bisstearamide were added to 100 parts of this polymer, mixed in a Henschel mixer, and then pelletized in a vent extruder. This pellet was continuously molded into a flat plate using an injection molding machine, and after 10 shots, the formation of deposits on the mold surface was observed to determine the lowest molding temperature at which deposits would occur. The temperature at which adhesion occurred was 280°C, and the molding area of the pellets obtained was extremely wide. The molded product had an Izot impact strength (measured according to ASTM D-256, with notches) of 18.5 kg·cm/cm.

Comparative Example 1 The same procedure as in Example 1 was carried out except that the phenolic antioxidant was not used. The discoloration of pellets and molded products is significant, and the molding temperature is lower than normal.
Even when molded at 200°C, fine roughness was observed, making it unsuitable as a molded product.

Comparative Example 2 The same procedure as in Example 1 was carried out except that glycidyl allyl ether was removed. The temperature at which adhesion occurred was extremely low at 200°C.

Comparative Example 3 4,4′-thiobis(6-t-
Diphenyl isodecyl phosphite was used in place of (butyl-3-methylphenol), but the molded product was pelletized in the same manner, and the Izo impact strength (notched) was measured to be 9.4 Kg/cm/
cm, which was an extremely low value compared to that of the molded product of Example 1.

Example 2 Glycidyl allyl ether 2 in Example 1
The same procedure was repeated except that 1 part of 4,4'-isopropylidene diphenol glycidyl ether was used instead of 1 part of 4,4'-isopropylidene diphenol glycidyl ether. The temperature at which adhesion occurred was 270°C.

Comparative Example 4 Alphaolefin oxide 168 (manufactured by Adeka Argus Chemical) was used in place of 4,4'-isopropylidene diphenol diglycidyl ether in Example 2.

The temperature at which adhesion occurred was 220°C, and there was almost no effect.

Example 3 Glycidyl allyl ether 2 in Example 1
The same procedure was carried out except that 0.5 part of glycidyl methacrylate was used instead of 1 part of glycidyl methacrylate. The temperature at which adhesion occurred was 260°C.

Example 4 The same procedure as in Example 1 was carried out except that glycidyl phenyl ether was used instead of glycidyl allyl ether. The temperature at which adhesion occurred was 270°C.

Example 5 The same procedure as in Example 1 was carried out except that glycerol polyglycidyl ether (Denacol EX313 manufactured by Nagase Sangyo) was used instead of glycidyl allyl ether, and magnesium stearate was used instead of ethylene bisstearamide. The temperature at which adhesion occurred was 270°C.

Example 6 Emulsion graft polymerization of 49 parts of styrene and 21 parts of acrylonitrile to 30 parts of polybutadiene was carried out, and 1.5 parts of 2,6-di-t-butyl-4-methylphenol was added to the obtained latex, which was then coagulated with acetic acid and washed with water. ,
A polymer was obtained by drying. Then, a granular polymer obtained by suspension polymerization of 70 parts of styrene and 30 parts of acrylonitrile, 50 parts each of the graft polymer, 0.5 part of dilauryl thiodipropionate, and 1 part of glycidyl methacrylate were mixed in a Henschel type mixer. ,
Pelletization was performed using a vented extruder. The pellets were formed into a sheet by uniaxial extrusion through a flat roll. Even during continuous sheeting for 2 hours at a resin temperature of 240°C, no deposits were observed on the roll, and the resulting sheet also had good gloss.

Comparative Example 5 The same procedure as in Example 6 was carried out except that glycidyl methacrylate was omitted. The roll lost its luster soon after the sheet was passed through the roll, and after 30 minutes, deposits became noticeable and the sheet lost its luster.

Example 7 18 parts of SBR latex containing 25% styrene (as rubber solids) was emulsion-polymerized with 32 parts of styrene, 43 parts of methyl methacrylate, and 7 parts of acrylonitrile, and octadecyl-3-
One part of (3',5'-di-t-butyl-4'-hydroxyphenyl)propionate was added, coagulated with dilute sulfuric acid, washed with water, and dried to obtain a powdery polymer. 0.5 part of glycidyl allyl ether was added to this polymer, mixed with a Henschel type mixer, and pelletized with a vent extruder.
Injection molding was carried out in the same manner as in Example 1. The temperature at which adhesion occurs is
It was 260℃.

Comparative Example 6 The same procedure as Example 7 was carried out except that glycidyl allyl ether was removed. The temperature at which adhesion occurred was 200°C.

Claims (1)

[Claims] 1. A thermoplastic resin composition comprising 0.01 to 5 parts by weight of a phenolic antioxidant and 0.05 to 10 parts by weight of glycidyl ether and/or glycidyl ester to 100 parts by weight of a butadiene rubber graft polymer resin.