JPS6047052A - Impact resistance modifier and thermoplastic resin composition containing the same - Google Patents

Abstract

PURPOSE:To provide an impact modifier capable of imparting high impact resistance and good moldability to thermoplastic resins, particularly, PVC, by blending a specified copolymer with a specified graft copolymer. CONSTITUTION:0.1-20pts. copolymer (A) obtd. by copolymerizing 3-30% unsaturated monomer and 97-70% copolymerizable vinyl monomer, is blended with 100pts. graft copolymer (B) obtd. by graft-polymerizing a monomer mixture consisting of 0-5% polyfunctional crosslinking agent and 95-100% at least one monomer selected from among an alkyl(meth)acrylate, an arom. vinyl compd. and a vinyl cyanide compd. onto a butadiene elastomer composed of a copolymer of at least 50% (poly)butadiene with no more than 50% copolymerizable vinyl compd. and contg. 0-5% polyfunctional crosslinking agent, in one- or multi-stage polymn.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to impact modifiers capable of imparting high impact resistance and good moldability.

Thermoplastic resin, especially vinyl chloride resin (PVO)
It is abbreviated as ) is widely used as a general-purpose resin, but its mechanical properties are not necessarily satisfactory.

That is, PVO has poor impact strength, particularly notched impact strength, and various methods have been proposed to improve this impact strength.

An effective method for the same amount of these proposals is to mix PVO with a graft copolymer obtained by graft polymerizing monomers such as styrene, methyl methacrylate, acrylonitrile, etc. to a conjugated diene elastomer. Eel graft copolymer is already commercially available as an impact modifier for PVA, and has greatly contributed to expanding the applications of PVO molded products.

By the way, in profile extrusion applications, it is extremely slippery, and even when molded under conditions where kneading is not effective,
There is a demand for compositions having high impact strength, and hitherto proposed impact resistance modifiers have not been fully satisfactory. In other words, graft copolymers, which are conventional impact modifiers in which a resin component having good compatibility with PVO is graft-polymerized onto an elastomer, cannot be used when processed at high temperatures, or when a relatively small amount of lubricant is used. etc., the graft copolymer is 1'
While it is uniformly dispersed in VC and exhibits excellent impact resistance,
When processed at low temperatures or when a large amount of lubricant is used, the graft copolymer aggregates in PVO and exhibits almost no impact resistance. We focused on the fact that uniform dispersion in IpvO greatly contributes to the development of impact strength. As a result, acrylic acid alkyl ester and methacrylic acid alkyl ester are formed into an elastic body whose main component is butadiene.

A resistant product containing a graft copolymer obtained by graft polymerizing an aromatic vinyl compound, a vinyl cyanide compound, etc., and a specific copolymer having all the essential constituents of unsaturated acid monomers in a specific range. A resin composition in which an impact modifier is blended with PVC dramatically promotes gelation even under conditions where the shear stress during molding is low and cross-linking is difficult, and it melts quickly to form a graft copolymer. is in a well-dispersed state, and the impact strength is improved.Moreover, this resin composition exhibits high impact resistance under a wide range of molding conditions, giving Fi even under conditions where it is hard to knead, and even lower impact strength. The present invention was achieved by discovering a method to improve processability and surface gloss.

That is, the gist of the present invention is that no polyfunctional crosslinking agent is used.
Acrylic acid alkyl ester is added to a butadiene-based elastomer consisting of a copolymer containing ~5% by weight of polybutadiene or Butashev 50% by weight or more and another vinyl compound capable of forming a valve type association with 50% by weight or less. 95 to 100% by weight of at least one monomer selected from the monomer group consisting of methacrylic acid alkyl esters, aromatic/vinyl compounds, and vinyl cyan compounds, and a polyfunctional crosslinking agent of 0 to 5N.
Graft-type polymers (~
Copolymer (B) obtained by copolymerizing 100 N parts with 3 to 30% by weight of an unsaturated acid monomer and 97 to 70% by weight of a vinyl monomer capable of forming a valve type. .1 to 20 parts by weight of the impact modifier.

In the present invention, the butadiene-based elastomer composed of the graft copolymer (N) is polybutadiene, or fc is a copolymer of 50 M% or more of butadiene and 50% by weight or less of another vinyl compound that can form a valve type association with the graft copolymer (N). It contains 0 to 5% by weight of a polyfunctional crosslinking agent.

Examples of other vinylation adducts that can co-N-group include acrylonitrile, styrene, acrylic acid alkyl esters, methacrylic acid alkyl esters, and the like. Examples of polyfunctional crosslinking agents include divinylbenzene, diacrylic esters, dimethacrylic esters, and those having an allyl group, that is, triallyl cyanurate.

Triallyl incyanurate, allyl acrylate.

Examples include allyl methacrylate, diallyl itaconate, diallyl phthalate, and the like. The amount of polyfunctional crosslinking agent is 5% by weight
Exceeding this is not preferable because it impairs elastic properties and reduces the effect of improving impact resistance.

The butadiene-based elastomer is preferably produced by a normal emulsion polymerization method using a known emulsifier-double polymerization initiator. Some emulsifiers include fatty acid salts, alkyl sulfate salts,
Alkylbenzene sulfonate.

Anionic surfactants such as alkyl phosphate ester salts and dialkyl sulfosuccinates, and nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, nlu and tan fatty acid esters, and glycerin fatty acid esters. Additionally, cationic surfactants such as alkylamine salts can be used. These surfactants can be used alone or in combination.

As a polymerization initiator, an inorganic initiator such as a normal persulfate, an organic peroxide, an azo compound, etc. may be used alone, or a combination of the above compounds and a sulfite, hydrogen sulfite,
It can also be used as a redox initiator in combination with thiosulfate, first metal salt, sodium formaldehyde sulfoxylate, etc. Preferred persulfates as initiators include sodium persulfate, potassium persulfate, ammonium persulfate, etc., and organic peroxides include t-butyl hydroperoxide, cumene hydroperoxide,
These include benzoyl peroxide and lauroyl peroxide.

A chain transfer agent may be used to adjust the molecular weight of the polymer, and alkyl mercaptans having 5 to 20 carbon atoms can be used.

Polymerization can be carried out at a temperature equal to or higher than the decomposition temperature of the polymerization initiator under normal emulsion overlay conditions. Polymerization can be carried out by adding the entire amount of the monomer or monomer mixture at once, or by continuously adding acetic acid to the entire amount or part of the monomer. However, M
+ stability.

From the viewpoint of removing the heat of heavy reaction, etc., it is preferable to carry out N@- without adding all or part of the amount. - The graft valve type public holiday (A) in the present invention is the above-mentioned butadiene-based elastic body 10
It is preferably obtained by grafting 25 to 125 parts by weight of a monomer or a mixture of monomers into an emulsion-based formulation in the presence of 0 parts by weight. The amount of monomer or monomer mixture to be graft polymerized is less than 25 parts by weight.
i"t, not only will it be difficult to operate the graft coagulation and drying process, but also PvC and Vvy): L, 7'
C field 8. ,) Resin assembly, 7) ヮ shape. This is not preferred because it is extremely poor in workability and tends to have low impact strength. 11ko125&! If it exceeds 100%, the effect of improving fI impact resistance will be small when blended with PVO.

As the monomer to be grafted, at least -mt selected from the monomer group consisting of acrylic acid alkyl esters, methacrylic acid alkyl esters, aromatic vinyl compounds, and vinyl cyan compounds can be used, and each monomer can be used alone as a VC or as a monomer. (a) and graft polymerization can be carried out in one stage or in multiple stages.

The acrylic acid alkyl ester preferably has an alkyl group having 2 to 10 carbon atoms, such as ethyl acrylate and globil acrylate.

Acrylic 1pu-butyl, acrylic 1pu-butyl.

Examples include hexyl acrylate, octyl acrylate, and 2-ethylhexyl acrylate.

The methacrylic acid alkyl ester is preferably one in which the alkyl group has 1 to 4 carbon atoms, such as methyl methacrylate, methyl methacrylate, brocobyl methacrylate, methacrylic ['l soprol, methacrylic e12]
Examples include n-butyl, isobutyl methacrylate, and tert-butyl methacrylate. Considering compatibility with PCV, methyl methacrylate is preferred.

In addition to styrene, aromatic vinyl compounds include
α-b′-substituted styrene, nuclear th-substituted styrene and its derivatives 1 such as α-methylstyrene.

Chlorstyrene, vinyltoluene, etc. are used.

Furthermore, examples of the vinyl cyanide compound include acrylonitrile, methacrylonitrile, etc. Graft polymerization is carried out to produce a butadiene-based elastomer.Subsequently, or again in another reactor under normal emulsion polymerization conditions, This can be carried out by adding, if necessary, a starting point 1], an N concentration regulator, a polyfunctional crosslinking agent, and the like. As the initiator, chain transfer agent, and polyfunctional blind crosslinking agent, those mentioned in the section regarding the butadiene-based elastomer can be used. In addition, when carrying out the graft polymerization, a mixture consisting of at least one monomer selected from the above-mentioned monomers to be grafted (95 to 100% by weight) and a polyfunctional crosslinking agent (0 to 5% by weight) is added in one step. Alternatively, it can be obtained by graft polymerization in multiple stages. Polyfunctional crosslinking agent is 5
If it exceeds % by weight, the compatibility of the grafted portion with PVOK will deteriorate and the effect of improving impact resistance will deteriorate, which is not preferable.

This graft polymerization can be carried out by adding the entire amount of the monomer at once to each stage, or continuously adding the entire amount or a portion of the fc monomer.

Further, the copolymer (B) in the present invention is an unsaturated acid monomer 3
~ Vinyl monomer 97 that can be traded with 30 units ~
It is obtained by subjecting 70% by weight to a valve mold, and the preferred manufacturing method is an emulsion method.

The unsaturated acid monomers include acid group-containing W*mers such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, cinnamic acid, maleic anhydride, and butenetricarboxylic acid. If the amount of the unsaturated acid monomer in the copolymer (B) is less than 5% by weight, the effect of improving impact resistance will be small, which is not preferable even when blended with the graft copolymer (A) and used as an impact resistance Kaga agent. . i
If the amount exceeds 7c5oM, the latex obtained by emulsification will not be stable, and the above-mentioned graft copolymer (A
) is also undesirable because it deteriorates latex stability and processability.

Examples of vinyl monomers that can coexist with unsaturated acid monomers include acrylic acid alkyl esters, methacrylic acid alkyl esters, and aromatic vinyl compounds.

Examples include vinyl cyanide compounds, etc.These are F'j
It can be spoken alone or by ear.

When producing the copolymer (B) by the total emulsion polymerization method, use the same emulsifier 1 polymerization initiator, chain transfer chiral 11, etc. that can be used in the production of the graft copolymer (A). It is possible to carry out cokyopolymerization in a similar manner to the preparation of graft copolymers (.

The impact modifier of the present invention is necessarily a blend of the above-mentioned graft copolymer (A) and co-N8 (B), and the distribution ratio thereof is the graft copolymer (~10 ′□′O
The amount of copolymer (B) is 0.1 to 20 parts by weight per part of N. 8i amount of copolymer (B) 7% Q. If the amount is less than 1 part by weight, the effect of improving impact resistance will be small, and if the amount exceeds 20 parts by weight, the effect of improving the impact resistance will decrease when both copolymers are latex blended. It is not preferable because it cannot be obtained as crab powder.

When carrying out the present invention, the graft copolymer (A) and copolymer (B) are blended at the above-mentioned distribution ratios in terms of gold solid content of each latex, and this blended latex is usually salted out. Alternatively, it may be coagulated by acid precipitation, filtered and washed with water, and recovered in powder form, or spray-dried or freeze-dried to be recovered in powder form.

By blending the impact resistance modifier of the present invention with various thermoplastic resins, it imparts high impact resistance and good processability to the thermoplastic resin, and also improves the weather resistance of molded products. It is something.

When the impact resistance modifier of the present invention is added to a thermoplastic resin, the effect of improving impact resistance is small, and when it exceeds 50 parts by weight, the inherent mechanical properties of the thermoplastic resin are impaired. Both are unfavorable because they can cause damage. Here, thermoplastic resin is PV
O, polycarbonate resin, polyester resin, acrylonitrile-styrene resin, methyl methacrylate-styrene resin, and the like. As the PVO, in addition to polyvinyl chloride, a vinyl chloride copolymer consisting of chloride, vinyl chloride, or more by weight can be used. Monomers copolymerized with vinyl chloride include ethylene, propylene, vinyl vinyl, vinylidene chloride, vinyl acetate, and acrylic ester.

Methacrylic esters and the like are used.

The blending of the impact modifier and thermoplastic resin of the present invention is favorable.
Preferably, it is in the form of a powder, and is formed using, for example, a pump blender, a Henschel mixer, or the like, and a known mixing machine, such as a mixing roll Banbury mixer 2 extruder, an injection molding machine, or the like. When blending, known stabilizers, plasticizers, lubricants, colorants, etc. may be added as necessary.

The present invention will be specifically explained below using Examples.

In addition, "parts" and "%" in the examples are "parts by weight" and "%", respectively.
It means "Megumi i%".

Example 1 (1) Production of graft copolymer Production of butadiene-based elastomer 1.3 Butadiene 75 parts Styrene 2'5',,/' Divinylbenzene 0.5 Hydroperoxide Sodium pyrophosphate 0. 5 Ferrous sulfate 0.01# Dextrose 1.0 Potassium oleate 0.5 Water 200 Heavy θ gold was carried out at 50° C. in a pressure autoclave according to the above composition. Polymerization was completed in 20 hours, and the average particle size of the obtained rubber was 0.17μ.

100 parts of the obtained butadiene-based elastomer latex (as solid content) was charged into a reaction vessel, 0.5 part of sodium formaldehyde sulfoxylate was added, and the temperature was raised to 7.
While maintaining the temperature at 0°C, a mixture of 32 parts of methyl methacrylate and 8 parts of ethyl acrylate to which 16 parts of cumenohydroboroxide (hereinafter abbreviated as OHP) was added was continuously added dropwise over 1 hour, and then for another 1 hour. After this, as a second stage, a mixture of 50 parts of styrene and 0.2 parts of OHP was continuously added dropwise over a period of 1 hour, and the mixture was held for approximately 2 hours. Then, in the third stage, a mixed solution consisting of 8 parts of methyl methacrylate, 2 parts of ethyl acrylate, and 4 parts of CHPo was added dropwise over 15 minutes, and the polymerization was completed by holding for another 1 hour to obtain the graft copolymer (A). Got latex.

(2) Production of copolymer (B) 200 parts of ion-exchanged water substituted with nitrogen was charged into a reaction vessel.
Dissolve 4 parts of semi-hardened beef fatty acid soap, 0.5 part of potassium persulfate, and 45 parts of ethyl acrylate.

A mixture consisting of 45 parts of methyl methacrylate and 10 parts of acrylic acid was added dropwise over 4 hours while keeping the temperature at 60°C.
After holding for a certain time, the mixture was divided into parts to obtain a copolymer (B) latex. The polymerization rate of each monomer was 99.5% or more.

(3) Latex blend and polymer recovery graft copolymer (A) 100 parts latex (as solid content)
was placed in a reactor equipped with a stirrer, 2 parts by weight (solid content) of copolymer (B) latex was added over 10 seconds with stirring, and stirring was continued for 15 minutes.

The obtained latex mixture was added to an aqueous sulfuric acid solution and solidified by acid precipitation, followed by washing, dehydration, and drying to recover the polymer in powder form (Example 1-1).

Note that the copolymer (B) was added in various amounts in the first test.
It is also shown in the table.

(4) Production of blended composition with vinyl chloride resin Vinyl chloride resin 1 with average degree of polymerization of 11oo [10 parts, 1.0 part of tribasic lead sulfate, 3 parts of dibasic stearin rR, 2.0 parts of lead stearate. Add 4 parts of stearic acid, 0.3 parts of stearic acid, 0.3 parts of polyethylene wax, and 10 parts of the modified modifier obtained in (3) above, and heat at 115°C in a Henschel mixer.
A homogeneous mixture was obtained. This vinyl chloride resin composition was molded into square rods using a 30 mm single screw extruder under the following conditions.

The impact strength of the molded product was measured in accordance with ASTM D=256, except that a test piece with a 2 g deep U-notch was used. Kon
The measurement results are shown in Table 1.7c.

From the results shown in Table 1 and above, it can be seen that by blending a specific amount of copolymer (B), the effect of improving impact resistance is the same as above.

Example 2 As copolymer (B), a mixture consisting of 50 parts of n-butyl acrylate, 35 parts of methyl methacrylate, and 15 parts of acrylic acid was polymerized in the same manner as in Example 1 (2) to obtain a copolymer. (B) Latex was obtained.

3 parts (solid content: 1) of this copolymer CB) latex was obtained in (1) of Example 1, and the f′Lfc graft copolymer (
A) Result of impact resistance of a vinyl chloride resin composition obtained by blending with 100 parts of latex (as solid content) and operating in the same manner as in Example 1 (3) and (4) using the same evaluation method. are shown in Table 2. The evaluation results of the copolymer (B) whose composition and addition were changed are also shown in Table Z.

Table 2 The abbreviations in Table 2 are as follows.

BA n-butyl niacrylate MAA: MMA methacrylate: methyl methacrylate A: itaconic acid AA niacrylic acid st: styrene EA ethyl niacrylate CA: crotonic acid MA methyl niacrylate Based on the above results, it was found that It can be seen that those with a small amount of unsaturated acid have little effect on improving impact resistance, and those with a large amount of unsaturated acid deteriorate the latex stability after blending.

Example 3 In Example 1 (1), butadiene 100i.

A polybutadiene elastomer latex was obtained in the same manner except that styrene was 0 parts. Five types of graft copolymers were obtained by changing the amount of the monomer mixture to be graft-polymerized to 100 parts (solid content) of this butadiene-based elastomer latex in three types. However, α5 was used as an additional emulsifier for the monomer mixture in which potassium oleate was graft-polymerized. In addition, as a polymerization initiator, sodium formaldehyde sulfoxylate and tertiary-butyl hydroperoxide were used as α for the monomer mixture to be graft-polymerized.
3%, α55chi was used. The ratio of each monomer in the graft polymerized monomer mixture was 75% methyl methacrylate.

15% styrene and 10% acrylonitrile.

To 100 parts (as solid content) of these latex (including graft copolymers) were added 3 parts (as solid content) of each of the TL copolymer (B) latex obtained in (2) of Example 1. Blend and operate in the same manner as (3) and (4) of Example 1 to obtain a vinyl chloride resin composition.

The impact resistance of these vinyl chloride resin compositions was measured using the same evaluation method as in Example 1 (4), and the results are shown in Table 3. January 1, Japan Patent Office Commissioner Shiga Gakudon 1, Indication of the case, Patent Application Sho S8-:5SS2S No. 2, Title of the invention: Impact resistance modifier and thermoplastic resin composition using the same, 3, Amendment. Patent applicant: 2-3-19 Kyobashi, Chuo-ku, Tokyo (603) Mitsubishi Rayon Co., Ltd. President Akio Kawasaki 4; Agent: Mitsubishi Rayon Co., Ltd., 2-3-19 Kyobashi, Chuo-ku, Tokyo Company No. 7, Contents of amendment (1) Clarification 11 (Correction of "Impact resistance modifier" in the 3rd to 4th lines of page 4 of Book 1 to "Impact resistance modifier".

(2) "Resin composition" on page 5, line 6 has been corrected to "impact modifier."

(3) On page 9, line 5, "1 emulsion polymerization recipe" is corrected to "emulsion polymerization method."

(4) l-P, C on page 10, line 15! VJ
Correct to 'fcfPVOJ.

(5) In the 12th negative line of the same statement, ``1 impact resistance modifier'' is corrected to ``1 impact resistance modifier''.

(6) Add astronomy after the 6th line on page 14.

"It can also be recovered by the method described in JP-A-57-187322." (7) On page 14, line 10, "weather resistance" is corrected to "appearance."

(8) On page 17, line 4, "Suru." is replaced with "Shita."
Correct.

(9) On page 18, line 15, "10 copies" is corrected to "113 copies."

0I r' of Example 2-5) in Table 2, page 21 of the same
MM A / S t / OA = 60 / 2
0/10 J to fMMA/5t10A=60/30
Corrected to /10J.

αυ "Butadiene-based elastomer latex" on page 22, lines 10 to 11. Corrected to "Polybutadiene elastomer latex J."

(6) On page 24', add astronomy before the first line.

"Example 4 30 parts of the modifier obtained in (1) to (3) of Example 1,
70 parts of polycarbonate resin, 0.2 parts of antioxidant, and 0.1 part of calcium stearate were mixed in a Kennel mixer, and the cylinder temperature was set at 240°C.
Pelletize with 0 to φ extruder and 1ζ. After drying, a test piece R was prepared using an injection molding machine, and the 5F-strength was measured using the same evaluation method as in Example 1 (4). The results are shown in Table 4. The results of various changes in the amount of copolymer (B) added are also shown in Table 4.

As shown in Table 4, the modifier according to the present invention exhibits excellent impact resistance improvement effects on polycarbonate resins. ”

Claims (1)

[Scope of Claims] 1. Polybutadiene or a copolymer containing 50% by weight or more of butadiene and 50% by weight or less of other vinyl adducts that can be copolymerized with it, containing 0 to 5% by weight of a polyfunctional crosslinking agent. A butadiene-based elastomer consisting of acrylic acid alkyl ester. selected from the monomer group consisting of methacrylic acid alkyl esters, aromatic vinyl compounds, and vinyl cyanide fractions
A graft copolymer obtained by one-stage or multi-stage graft polymerization of a monomer or a monomer mixture consisting of 95 to 100% by weight of at least one monomer and 0 to 5% by weight of a polyfunctional crosslinking agent. Coalescence (~100 parts by weight, 3 to 3 parts by weight of unsaturated acid monomer)
0% by weight and vinyl monomers copolymerizable with 97~
Copolymer (B) obtained by copolymerizing 70% by weight 0.
An impact modifier comprising 1 to 20 parts by weight. Z A thermoplastic resin composition having good impact resistance and moldability, comprising 100 parts by weight of a thermoplastic resin and 3 to 50 parts by weight of the modifier according to claim 1. (5) The thermoplastic resin composition according to claim 2, wherein the thermoplastic resin is a vinyl chloride resin. 4. The thermoplastic resin composition according to claim 2, wherein the thermoplastic resin is a polycarbonate resin. 5. The thermoplastic resin composition according to claim 2, wherein the thermoplastic resin is a polyester resin. & The thermoplastic resin composition according to claim 2, wherein the thermoplastic resin is an acrylonitrile-styrene resin. 2. The thermoplastic resin composition according to claim 2, wherein the thermoplastic resin is a methyl methacrylate-styrene resin.