JPS6026424B2 - Impact resistant resin composition - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an impact-resistant resin composition, and more particularly to an impact-resistant resin composition that is excellent in processability, appearance, heat resistance, and various physical properties. Amo resin is a typical impact-resistant resin and is widely used in the fields of electrical product cases, automobile inner and outer bags, and household goods. In the resin processing industry, it has recently become common to make molded products thinner and to perform hot runner molding for the purpose of resource conservation and production cost reduction. As a result, the resins used are increasingly required to have higher performance. In other words, in addition to requiring thermal stability when molding at high temperatures compared to conventional moldings, it also has excellent impact resistance and heat resistance even for thin-walled molded products, and is highly versatile when molding large molded products and high-speed molding. It is necessary to have a small amount and good fluidity. Furthermore, as the range of applications of resins expands, the environment in which they are used also covers a wide temperature range, so good impact resistance is required, especially at low temperatures. Naturally, the appearance of a resin product is also one of the important properties of the resin in determining its commercial value. It has been considered extremely difficult to obtain a device with balanced performance. For example, it is known that in order to improve processability, the molecular weight of the component that forms the resin matrix can be reduced by 4.
In some cases, the appearance of resin products may also be deteriorated. On the other hand, increasing the molecular weight of the matrix component improves the strength and heat resistance of the resin, but conversely it reduces processability, so it is not possible to obtain a well-balanced material by simply adjusting the molecular weight of the matrix component. It was difficult. The characteristics of the components that form the resin matrix play an important role in determining the performance of the resin, and methods for improving the performance of the resin have been proposed from this perspective. For example, Tokuko Sho 5
No. 3-4862' This is a polymer to be added to the graft polymer, in which a copolymer with a large molecular weight and a copolymer with a large molecular weight are mixed in a ratio of 1:5 to 5:1, and A method has been proposed in which both copolymers are used in which the difference in specific viscosity of a 0.1% by weight solution of dimethylformamide is 0.02 to 0.09. According to this method, it is possible to obtain well-balanced properties with excellent moldability, physical properties, and appearance. However, the balance of physical properties, including properties that have been emphasized in recent years for this type of resin, such as impact resistance at low temperatures, difficulty in orientation when molding thin-walled products, and thermal stability during high-temperature molding, is important. Considering this, even with this method, it is difficult to say that the resin composition has been improved to a sufficiently satisfactory level. Taking into account the above points, the present inventors have found that in addition to good impact resistance and processability, it can be stably molded at high temperatures, has small orientation when molding thin-walled products, and has excellent appearance such as gloss and heat deformation resistance. As a result of intensive research into a well-balanced impact-resistant resin composition that has excellent properties, the present invention was achieved. That is, the gist of the present invention is to combine two or more monomers selected from the group consisting of a vinyl aromatic compound monomer, a vinyl cyanide compound monomer, and a (meth)acrylic acid ester monomer into a rubbery polymer. A vinyl aromatic compound monomer and a vinyl cyanide compound monomer are added to the graft polymer Polymer A in which the weight fraction of the rubbery polymer in the polymer is in the range of 10 to 50%. In an impact-resistant resin composition in which the weight fraction of the rubbery polymer after blending is 5% or more by blending Polymer B, a British polymer obtained by copolymerizing with Polymer B, the polymer B is a copolymer. The copolymer [1] consists of a copolymer [1] having a weight content of a vinyl cyanide compound single base in the range of 26 to 31% and a copolymer [m] having a weight content of 21 to 26%. and copolymer

The difference in the weight content of vinyl cyanide compound monomer with [0] is 5% or more, and the copolymer [1] and the copolymer

The weight mixing ratio of [0] is 3:
The impact resistant resin composition is in the range of 7 to 7:3. Next, the constituent elements of the present invention will be explained in detail. Rubber mass combinations in the present invention include natural rubber, polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, polyisobutylene, polychloroprene, acrylic rubber, ethylene-propylene rubber, ethylene-propylene terpolymer, etc. However, from the viewpoint of improving impact resistance at low temperatures, butadiene (co)polymer consisting of 100 to 7% by weight of butadiene and 0 to 3% by weight of styrene is used as a rubber polymer. Preferably, coalescence is used. The vinyl aromatic compound monomer in the present invention is styrene,
Q-methylstyrene, vinyltoluene, chlorostyrene, vinylnaphthalene, etc., and vinyl cyanide compound monomers include acrylonitrile and methacrylonitrile. Examples of the (meth)acrylic acid ester monomer include methyl, ethyl, propyl, n-butyl, and phenyl esters of acrylic acid and methacrylic acid. A combination of styrene and acrylonitrile is particularly preferred as the monomer mixture. The graft polymer in the present invention, that is, Polymer A, is a rubbery polymer containing two or more monomers selected from the group consisting of a vinyl aromatic compound monomer, a vinyl cyanide compound monomer, and a (meth)acrylic acid ester monomer. It is a product obtained by graft polymerization of a mixture consisting of children, and the weight fraction of the rubbery polymer in the polymer is 10 to 50%,
Preferably it is in the range of 20 to 40%. Polymer A was produced by any of the currently known polymerization methods, such as emulsion polymerization, solution polymerization, bulk polymerization, bulk-suspension polymerization, emulsion-suspension polymerization, and emulsion bulk polymerization. It doesn't matter if it's something. Further, the polymerization of Polymer A is preferably carried out in the presence of a radical polymerization initiator.
As a radical polymerization initiator, cumene hydroperoxide, penzoyl peroxide, lawaloyl peroxide,
Organic peroxides such as menthane peroxide and t-butyl hydroperoxide are preferred. Further, a redox initiator consisting of an organic peroxide and an iron salt can also be used.
The resin composition of the present invention is obtained by blending the polymer A with a copolymer of a vinyl aromatic compound monomer and a vinyl cyanide compound monomer, that is, a polymer B. The feature of the present invention is that the polymer B is a copolymer with a high weight ratio of vinyl cyanide compound monomer (monomer Q) [1
] and low copolymer

The point is that a mixture of [0] was used. These English polymers [1] and English polymers [n] each have a car content of 26 to 26, respectively, as measured by the nitrogen analysis table.
31% and 21-26%, copolymer [1] and copolymer

The difference in weight content of monomer Q in [0] should be 5% or more. Copolymer [1] and copolymer

The mixing ratio with [0] can range from 3:7 to 7:3. The content of monomer Q in the copolymer is set within the above range when copolymer [1] and copolymer

This is done in connection with making the difference in weight content of monomer Q in [0] 5% or more, even if the difference in weight content of monomer Q is in the range of 5% or more. However, the weight content of monomer Q in copolymer [1] and copolymer [day] is 26 to 31% and 21%, respectively.
If it is carried out at the lowest level other than ~26% or even higher, the resulting resin composition will have undesirable effects such as a decrease in strength and coloring during high temperature molding, which will defeat the purpose of the present invention. . On the other hand, copolymer [1], copolymer [
0], the amount content of monomer Q is 26 to 31%, 2
Even if it is 1 to 26%, if the difference in the weight content of monomer q in these copolymers is less than 5%, the characteristics caused by mixing the two types of copolymers will not appear, and the same as above will occur. The object of the present invention cannot be achieved because the physical properties deteriorate. Furthermore, it is preferable that the English polymer [1] has an intrinsic viscosity of 0.5 to 0.8 when measured in methyl ethyl ketone (MEK) at 3°C, and that of the copolymer [D] is 0. A range of .3 to 0.5 is preferred. Therefore, the present invention provides the above-mentioned Hakama Kosho Kyukyu-
It is clear that this is essentially different from No. 4862. Also, copolymer [1] and copolymer

The mixing ratio of [0] is 3:7~7
:3 is not preferable because if the content of the English polymer [1] exceeds the above range, the molding processability of the resin composition ultimately obtained will be greatly reduced. On the contrary, English polymer

If [0] is larger than the above range, the molding processability of the resin composition finally obtained will improve, but the impact strength, heat deformation resistance, etc. of the obtained product will deteriorate, which is not preferable. Copolymer [1] and English polymer

When the ratio with [0] is within the above range, the resin composition not only mutually compensates for the drawbacks caused by using each copolymer alone, but also has excellent properties that cannot be expected from using each copolymer alone. can get things. Copolymer [1], Copolymer [0]
] may be carried out by any of the currently known polymerization methods, such as emulsion polymerization, solution polymerization, bulk polymerization, and suspension polymerization. The resin composition according to the present invention has polymer A
Polymer B is blended with the rubbery polymer so that the weight fraction of the rubbery polymer after blending is 5% or more and 30% or less. When the proportion of rubbery polymer is less than 5% by weight, impact resistance decreases, and when it exceeds 30%, heat deformation resistance and various physical properties (
In particular, it is undesirable because the mechanical strength decreases. As for the method of mixing Polymer A and Polymer B, if both are produced by an emulsion polymerization method, they can be mixed in an emulsion state. When both are produced by solution polymerization, they can be mixed in the state of a polymer solution. In addition, various forms such as beads together, powders together, beads and powder, etc. can be mixed together. In this case, various mixing processing machines such as kneading using an extruder, a Henschel mixer, a Banbury mixer, and a heating roll may be used as appropriate depending on the mixing mode. At this time, if necessary, stabilizers, lubricants, plasticizers, nourishing agents, dyes and pigments, etc.
Flame retardants, fillers, etc. can be added. In addition to sufficient impact resistance and processability, the impact-resistant resin composition thus obtained has excellent impact resistance at low temperatures, good thermal stability during high-temperature molding, and is suitable for thin-wall molding at high speeds. It is a resin composition with very balanced properties, having little orientation, excellent heat resistance as a product, and excellent appearance such as gloss, and its industrial utility value is extremely large. The present invention will be explained in more detail with reference to Examples below.
The scope of the present invention is not limited by these Examples unless it goes beyond the spirit thereof. In the following Examples and Comparative Examples, parts and % mean parts by weight and % by weight unless otherwise specified. Examples 1 to 3 [11 Polymer A Po IJ butadiene latex [a' (solid content) Isobe Po IJ butadiene latex 'b' (solid content) 2 Styrene
21 Acrylonitrile 9 Tertiary decyl mercaptan 0.2 Potassium rosinate -○ Potassium hydroxide 0.03 Water (including water in latex) 120 Here, polybutadiene latex 'a' has a gel content of 80.4 %,
Polybutadiene latex'b} has a gel content of 481% and an average particle size of 0.26 mm.
It is spherical. The above mixture was charged into a reactor equipped with a jacket and a rope machine, and after replacing the air inside with nitrogen, the inner temperature was raised to 4,000 degrees while controlling the jacket at 70:00, and the water and base steel were dissolved. 0.3 part of sodium pyrophosphate, 0.3 part of dextrose, 0.006 part of ferrous sulfate, and 0.1 part of cumene hydroperoxide were added and reacted. One hour after starting the reaction, the following mixture was added gradually over a period of 2 hours to determine the polymerization rate. A 9% graft polymer latex was obtained. styrene
21 parts acrylonitrile 9 tertiary lead decyl mercaptan 0.2 potassium rosinate 1.0 potassium hydroxide
0.03 cumene hydroperoxide
0.1 water 40 parts of this graft polymer latex (as solid content)
After adding 0.5 part of 2,6-di-tert-butyl para-cresol as an anti-aging agent, the mixture was coagulated, washed with water and dried to obtain a graft polymer powder. ■Polymer B In a reactor with the same structure as used in the production of the above ABS resin, 74 parts of styrene, 26 parts of acrylonitrile, 0.6 parts of tertiary lead decyl mercaptan, and 0.6 parts of water are added.
240 disproportionated rosin
2.0, and after replacing the internal air with nitrogen, reduce the internal temperature to 4 pm while controlling the jacket to 6 pm.
Add 0.1 part of hot sodium formaldehyde sulfoxylate, 0.015 part of ferrous sulfate, 0.15 part of disodium ethylenediaminetetraacetate, and 0.1 part of cumene hydroperoxide to 1 part of water. and reacted. After the reaction was continued for 2 hours after starting the reaction, the inside of the reactor was cooled, solidified, washed with water, and dried to obtain an AS polymer powder. During the above polymerization, the charging ratios of styrene and acrylonitrile and the amount of tertiary decyl mercaptan (TDM) were varied to obtain four types of AS polymers as shown in Table 1. Table 1 x Nitrogen analysis (Coleman applying Dumas method)
{31 Blend and Physical Property Measurement The ABS resin obtained by the above method and the AS polymer were blended, and the amount of rubbery polymer in the final resin composition was 1.
It was set to 7%. At this time, the AS polymer component contains AS-1 and AS-2 in a ratio of 1:
The mixing ratio was varied in the range of 2 to 2:1 (Examples 1 to 3)
. Such a formulation contains 10 ethylene bisstearylamide and 1. After adding and mixing the anchor part, the mixture was made into pellets at 200 qo using a 4-side extruder, and further a test piece was molded by the method shown below and its physical properties were measured. The fluidity during processing was measured at 200 qo using a Koka type flow tester. Izod impact strength is 20 using a 5oz injection molding machine.
A predetermined test piece was molded at 000 and measured at 0 and -3000 according to the method of ASTM D256. Glossiness was measured using 200 test pieces molded using a 5 oz injection molding machine and 1 test piece molded in a cylinder at a temperature of 280°C.
ASTM
Measured according to D523. The heat distortion temperature was measured according to the method of ASTM D648 using a test piece molded at 200q○ using a 5-ounce injection molding machine. To determine the degree of orientation of the resin, a 1/8 inch thick plate sample was molded at 200°C using a 3.5 oz injection molding machine, and test pieces of a predetermined shape were extracted from this sample parallel to and perpendicular to the flow direction. The Izod impact strength of each test piece was measured at 23qo according to ASTM D256.
The value calculated by the following formula was used as a measure of the degree of orientation. Compounding degree = 1 Izo and Soto impact strength of test pieces cut at right angles Table 2 shows the measurement results of physical properties that are higher than Izoso impact strength of parallel cut test pieces. Comparative Examples 1 to 5 Comparative Examples 1 to 4 are those in which AS polymers AS-1, AS-2, AS-3, and AS-4 are individually blended with the ABS resin used in the examples. Example 5 is a mixed system in which the amount of rubbery polymer in the final resin composition is 17%.
I made it so that This formulation contains an additional 10% of ethylene bisstearylamide. After adding and blending the foundation, pelletization was performed in the same manner as in Examples 1 to 3. Table 2 shows the results of measuring various physical properties using the methods described in Examples 1 to 3. As is clear from Table 2, the composition of the present invention has high fluidity, excellent moldability, and good impact strength at room temperature and low temperature. It has excellent and well-balanced properties in terms of other physical properties and appearance. On the other hand, when the two types of AS polymers are not used and are mixed alone, even if the fluidity is good, the impact strength is low, the degree of orientation is high, and the heat distortion temperature is low (Comparative Example 1 ), improving the impact strength has an adverse effect on fluidity and thermal stability (Comparative Examples 2 and 4). Even if an attempt is made to balance fluidity and impact strength, when used alone, the level is low, the degree of orientation is not good (Comparative Example 3), and balanced properties are not exhibited. Also, even if two types of AS polymers are mixed and used. If the difference is less than 5%, not only will the impact strength at room temperature be low, but also the degree of orientation will be large, making it impossible to obtain sufficient effects (
Comparative Example 5). Example 4 The same procedure as in Example 1 was carried out except that only 40% of polybutadiene [a} was used as the rubber component of polymer A in Example 1. The physical properties of the obtained resin composition were as follows. Fluidity (20 pi C, × 10-3 cc/sec 23.5 izot impact strength (k9 guy/enemy) 2 chi 0 32.7〃
-30q0 13.4 Heat distortion temperature (00) 90.2 Surface glossiness (
%) Matsupi C 78280pm 0 63 (Female retention job) Orientation degree 0.26 Examples 5-7
Comparative Examples 6 to 10 {1' Polymer A, ST/MMA Production of graft body (M old S) SBR latex (solid content) 48 parts Methyl methacrylate 14.5 Potassium sulfate
0.2 Water (including water in latex) 150 Here, the SBR latex has % bound styrene, 80% gel content, and 0.1 average particle size. The above mixture was charged into a reactor equipped with a jacket and a rope strainer, and after replacing the air inside with nitrogen, the jacket was heated to 80 to 85 qo, the internal temperature was raised to 8 qo, and the following two types of mixtures were prepared. They were continuously added through separate lines over a period of 1 lull to obtain a graft polymer with a polymerization rate of 90%. Mixture 1 Methyl methacrylate 15.
5 parts styrene 22.5 parts diisopropylbenzene hydroperoxide 0.2 Mixture 2 Water 16 parts Sodium formaldehyde sulfoxylate 0.1 Potassium hydroxide 0.1 An anti-aging agent is added to the base (as solid content) of this graft polymer latex. After adding 0.5 part of 2,6-di-tert-butyl para-cresol, the mixture was coagulated, washed with water, and dried to obtain a graft polymer powder. The final rubber content of the obtained graft polymer (M mother) was adjusted to 17% as in Examples 1 to 3, and AS-1 to AS-4
were blended at various mixing ratios and evaluated. As is clear from Table 3, the composition of the present invention has high fluidity, good moldability, and good impact strength and orientation at room and low temperatures. On the other hand, as shown in Comparative Examples 6 to 10, even if a single AS polymer or two types of AS polymers are used, if the difference in bond AN is less than 5%, the fluidity and other physical properties will deteriorate. Poor balance. Examples 8 to 10, Comparative Examples 11 to 15 '11 Polymer A, Production of MMA/AN grafted body Polybutadiene latex (solid content) 4 Kato methyl methacrylate 25 Acrylonitrile
5 tertiary lead decyl mercaptan
0.2C Potassium dinate Potassium monohydroxide 0.2 Water (including water in the latex) 140 Here, the polybutadiene latex is the same as the polybutadiene latex 'a' used in Examples 1 to 3. Using. The reaction conditions were the same as in Examples 1 to 3 except that the following components were used in the mixture to be added continuously, and the final polymerization rate was 9.
A 0.2% graft polymer latex was obtained. Methyl methacrylate 25 parts Acrylonitrile
5 tertiary lead decyl mercaptan
0.2 Potassium rosinate 1.0 Potassium hydroxide 0.2 Cumene hydroperoxide 0.1 Water
40 This graft polymer latex 10
After adding 0.5 part of 2,6-tertiary butyl para-cresol as an anti-aging agent to the base (solid content), the mixture was coagulated, washed with water, and dried to obtain a graft polymer powder. The obtained graft polymers were blended with AS-1 to AS-4 at various mixing ratios with a final rubber content of 17% in the same manner as in the sprues of Examples 1 to 3, and evaluated. As is clear from Table 4, similar to the case of ABS and M spots,
It has high fluidity and excellent moldability, and has good impact strength and orientation at room and low temperatures. On the other hand, as shown in Comparative Examples 6 to 10, even if a single AS polymer or two types of AS polymers are used, if the bond difference is less than 5%, the balance between fluidity and other physical properties is poor. It is defective. Table 3 Table 4

Claims (1)

[Claims] 1. A rubbery polymer containing a mixture of two or more monomers selected from among a vinyl aromatic compound monomer, a vinyl cyanide compound monomer, and a (meth)acrylic acid ester monomer. A vinyl aromatic compound monomer and a vinyl cyanide compound monomer are added to a graft polymer polymer A in which the weight fraction of the rubbery polymer in the polymer obtained by graft polymerization is in the range of 10 to 50%. In an impact-resistant resin composition in which a copolymer B obtained by copolymerization is blended so that the weight fraction of the rubbery polymer after blending is 5% or more, the polymer B is The weight content of vinyl cyanide compound monomer is 2
Copolymer [I] ranging from 6 to 31% and 21 to 26%
copolymer [II] within the range of copolymer [I
] and copolymer [II], the difference in weight content of vinyl cyanide compound monomer is 5% or more, and the weight mixing ratio of copolymer [I] and copolymer [II] is 3: An impact-resistant resin composition characterized in that the ratio is in the range of 7 to 7:3.