JPS6210125A - Block copolymer composition - Google Patents

Abstract

PURPOSE:A block copolymer composition suitable as a resin modifier, composed of an aromatic vinyl copolymer having peroxy groups in the main chain and a peroxy group-free (co)polymer having a monomer composition different from that of the former. CONSTITUTION:The purpose block copolymer composition is composed of 5-95wt% copolymer (A) prepared by radical-copolymerizing 50-99.4wt% aromatic vinyl monomer (e.g., styrene) with 0.1-30wt% copolymerizable monomer (e.g., methyl acrylate) and 0.5-20wt% radical-copolymerizable peroxycarbonate of the formula (wherein R1 is H or a 1-2 C alkyl, R2 is H or methyl, R3 and R4 are each a 1-4 C alkyl, R5 is a 1-12 C alkyl, phenyl or the like, and n is 1-2) and 95-5wt% (co)polymer (B) comprising a radical-polymerizable monomer, containing no monomer of the formula and having a monomer composition different from that of component A.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a copolymer having a peroxy group in a polymer mainly composed of one or more aromatic vinyl monomers. The present invention relates to a block copolymer composition useful for modifying resins, which is composed of A and a (co)polymer B that has a different monomer composition and does not contain peroxy groups.

In recent years, with the development of new technology for polymer blends, attempts to add functional groups to polymers have been actively investigated. Among these, those with peroxy groups added to the polymer main chain are
It is a very interesting material because of its high reactivity.

(Prior art) For example, "Plastilant Color Check" (Pla
ste 'und Kautschuku, 26 (3
) 121 (I979)) proposed a product in which a peroxide having a (meth)acrylic type double bond was copolymerized with a (meth)acrylic acid ester monomer and a peroxy group was introduced into the polymer main chain. There is.

Similarly, Japanese Patent Publication No. 55-30790 proposes a radical copolymerizable peroxycarbonate having an allylic double bond represented by the following general formula (II).

The radical copolymerizable peroxycarbonate represented by the general formula (II) is (wherein, R6 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R7, R is an alkyl group having 1 to 4 carbon atoms, (R3 represents an alkyl group having 1 to 12 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms.) Regarding this radical copolymerizable peroxycarbonate having an allyl type double bond, Japanese Patent Publication No. 57-2
No. 6617, copolymer with vinyl chloride in Japanese Patent Publication No. 57-26619, JP-A-56-139514
In Japanese Patent Publication No. 57-50802, a copolymer with diallyl phthalate was proposed, and in Japanese Patent Publication No. 57-42083, a copolymer with vinyl acetate was proposed. ,
It has also been confirmed that these copolymers have self-crosslinking properties and grafting properties.

(Problem to be Solved by the Invention) However, when attempting to blend these copolymers with other resins, there is generally no compatibility between the resins, so a graft reaction occurs locally, causing the blended resin to This has the disadvantage of causing a decrease in mechanical strength and a decrease in physical properties due to phase separation phenomena.

Furthermore, since the radical copolymerizable peroxycarbonate represented by the general formula (II) has an allyl type double bond, it has good copolymerizability with a monomer having a non-conjugated double bond. However, aromatic vinyl monomers,
It has the disadvantage that it does not copolymerize with conjugated monomers such as (meth)acrylic acid ester monomers. Furthermore, in order to improve this drawback, attempts have been made to add or contain copolymerizable monomers, but this has resulted in the problem that it is difficult to exhibit the intended physical properties.

On the other hand, in recent years, methods for producing various block copolymer compositions have been developed, and blended resins with new properties are produced by blending the obtained block copolymer composition and other resins under melting conditions. Attempts are being made to manufacture According to this method, large phase separation in the blend resin disappears due to the properties of the block copolymer composition, and a uniform blend resin is obtained. However, since there are no chemical bonds at the interface between the blended resins, in particular,
Blended resins had the drawback of significantly lower mechanical strength.

In order to improve these drawbacks, the present inventors previously disclosed in Kokai Technical Report No. 83-6603 that the present invention consists of a copolymer (A) and a (co)polymer port, and that only the copolymer (A) contains peroxycarbonate. Block copolymer compositions into which groups have been introduced are disclosed. This block copolymer composition has excellent properties such as good dispersion stability during polymer blending and improved interfacial strength between blended resins.

However, since the peroxide having a double bond used is a radically copolymerizable peroxycarbonate represented by the general formula (n), the monomer composition of copolymer A is different from that of vinyl acetate, vinyl chloride, etc. It is limited to monomers having non-conjugated double bonds, which has the drawback of adversely affecting the heat resistance, weather resistance, chemical resistance, electrical insulation properties, etc. of the blended resin. Furthermore, since the (co)polymer is a styrene polymer, it is possible to impart rigidity, surface gloss, etc., but it is difficult to impart impact resistance, weather resistance, etc.

(Means for Solving the Problems) The present inventors have further conducted intensive research to eliminate these conventional drawbacks, and as a result, the block copolymer composition of the present invention shown below has been developed to overcome these conventional disadvantages. The present invention was completed based on the knowledge that all the drawbacks could be eliminated.

That is, the present invention provides (a) 50-99.4% by weight of one or more aromatic vinyl monomers and 0.1-99.4% by weight of a monomer copolymerizable with the aromatic vinyl monomer. 30% by weight of a copolymer A obtained by radical polymerization of 0.5-20% by weight of a radical copolymerizable peroxycarbonate represented by the following general formula (I), and (b) a radical ( Co) Consists of one or more polymerizable monomers, does not contain a radical copolymerizable peroxide carbonate represented by the following general formula (I), and has a monomer composition different from the copolymer A. This is a block copolymer composition consisting of 95-5% by weight of (co)polymer B.

Here, the radical copolymerizable peroxycarbonate represented by the general formula (I) is defined as (wherein, R represents a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, and R2 represents a hydrogen atom or a methyl group. , R3
and R4 each represent an alkyl group having 1-4 carbon atoms, R5
represents a group selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a phenyl group, and a cycloalkyl group having 3 to 12 carbon atoms. n represents an integer of 1 or 2. ) is a compound represented by

(Function) In the present invention, the structural unit derived from the aromatic vinyl monomer in copolymer A is an essential component. The reason is that aromatic vinyl polymers have excellent heat resistance, weather resistance, processability,
This is because it has excellent electrical insulation properties.

In the present invention, specific examples of the aromatic vinyl monomer used include styrene, α-methylstyrene, m-chlorostyrene, and p-chlorostyrene. Preferably styrene.

The amount used is 50-99.4% by weight, preferably 6
It is 0-98.5% by weight. If it is less than 50% by weight,
Copolymer A extremely loses the properties of an aromatic vinyl polymer, which is not preferable. Furthermore, it is not preferable that the radical copolymerizable peroxycarbonate represented by the general formula (I) necessarily exceeds 20% by weight. Moreover, if it exceeds 99.4% by weight, the radical copolymerizable peroxycarbonate represented by general formula (I) will necessarily be less than 0.5% by weight, which is not preferable. Furthermore, in this amount, the amount of active oxygen in the block copolymer composition of the present invention becomes less than 0.002% by weight, which is not preferable.

That is, when blending with other resins, since the amount of active oxygen is small, the grafting efficiency of the other resins and the block copolymer composition of the present invention is extremely reduced.

Furthermore, in the present invention, in the copolymer A, -general formula (I
) is also an essential component. This is because, when this radical copolymerizable peroxycarbonate is introduced into the copolymer A, it thermally decomposes during melting to generate radicals, which causes a graft reaction.

Specifically, the radical copolymerizable peroxycarbonates used include t-butylperoxyacryloyloxyethyl carbonate, 1-hexylperoxyacryloyloxyethyl carbonate), 1.1.3.3-
Tetramethylbutylperoxyacryloyloxyethyl carbonate, cumylperoxyacryloyloxyethyl carbonate, p-isopropylcumylperoxyacryloyloxyethyl carbonate, t-butylperoxymethacryloyloxyethyl carbonate, t-amylperoxymethacryloyloxyethyl carbonate ,
1,1.3.3-Tetramethylbutylperoxyacryloyloxyethyl carbonate, cumylperoxyacryloyloxyethyl carbonate, t-butylperoxyacryloyloxyethoxyethyl carbonate, t-
Hexylperoxyacryloyloxyethoxyethoxyethyl carbonate, cumylperoxyacryloyloxyethoxyethoxyethyl carbonate, t-butylperoxymethacryloyloxyethoxyethyl carbonate, t-amylperoxymethacryloyloxyethoxyethyl carbonate, cumylperoxyacryloyloxyethoxyethoxy Ethyl carbonate, t-butylperoxyacryloyloxyisopropyl carbonate, t-hexylperoxyacryloyloxyisopropyl carbonate, 1.1
．． 3.3-Tetramethylbutylperoxyacryloyloxyisopropyl carbonate, cumylperoxyacryloyloxyisopropyl carbonate, t-butylperoxymethacryloyloxyisopropyl carbonate, -amylperoxymethacryloyloxyisopropyl carbonate, 1,1.3 Examples include 3-tetramethylbutylperoxyacryloyloxyisopropyl carbonate and cumylperoxyacryloyloxyisopropyl carbonate. Preferably t-
Butyl acryloyloxyethyl carbonate, t-hexyl peroxy acryloyloxyethyl carbonate,
Examples include t-butylperoxymethacryloyloxyethyl carbonate, t-hexylperoxyacryloyloxyethyl carbonate, and t-butylperoxyacryloyloxyethoxyethyl carbonate.

The amount used is 0.5-20% by weight based on copolymer A.
It is. Preferably it is 1-15% by weight. If it is less than 0.5% by weight, the amount of peroxycarbonate groups introduced into the copolymer A will be small, and the amount of active oxygen in the block copolymer composition will be less than 0.002% by weight. Therefore, the grafting ability with other resins, which is the object of the present invention, is not sufficiently exhibited, which is not preferable. Moreover, if it exceeds 20% by weight, it is not preferable because it may cause gelation during polymerization or the copolymer A may lose the physical properties of an aromatic vinyl polymer.

In the present invention, a component of copolymer A is a radical copolymerizable monomer copolymerizable with an aromatic vinyl monomer. This is mainly for adjusting the glass transition temperature of the aromatic vinyl polymer. The amount is 0.1-30% by weight,
Preferably it is 0.5-25% by weight. This is because if the amount exceeds 30% by weight, Copolymer A rapidly loses its physical properties as an aromatic vinyl polymer.

If the amount is less than 0.1% by weight, the glass transition temperature of the aromatic vinyl polymer cannot be adjusted sufficiently. Specifically, (meta)
Methyl acrylate, etinope (meth)acrylate, (meth)acrylic acid ester monomers such as -butyl (meth)acrylate, vinyl ester monomers such as vinyl acetate and vinyl propionate, acrylonitrile, methacrylonitrile unsaturated nitrile monomers such as butadiene,
Conjugated diene monomers such as isoprene, unsaturated fatty acid monomers such as acrylic acid and methacrylic acid, α-olefin monomers such as ethylene, propylene, and butene-1, and vinyl halides such as vinyl chloride and vinylidene chloride. Examples include quantifiers, but they are selected depending on the purpose.

In the present invention, there are no particular limitations on the monomer used during the (co)polymerization holiday, as long as the monomer composition of copolymer A is different. Depending on the properties required for the block copolymer composition obtained by the present invention and the purpose of modifying other resins,
This is because the monomer is selected.

In general, radically polymerizable monomers are preferred, specifically aromatic vinyl monomers such as styrene, α-methylstyrene, and p-methylstyrene, methyl (meth)acrylate, and (meth)acrylic monomers. (meth)acrylic acid ester monomers such as ethyl acid and n-butyl (meth)acrylate; vinyl ester monomers such as vinyl acetate and vinyl propionate; unsaturated nitrile monomers such as acrylonitrile and methacrylonitrile; conjugated diene monomers such as butadiene and isoprene, unsaturated fatty acid monomers such as acrylic acid and methacrylic acid, ethylene, propylene, and butene.
Examples thereof include α-olefin monomers such as 1 and halogenated vinyl monomers such as vinyl chloride and vinylidene chloride.

The block copolymer composition of the present invention must have properties specific to block copolymers, such as good dispersion stability in other resins.

Therefore, the amount of copolymer A in the block copolymer composition should be 5-95% by weight and the amount of (co)polymer B should be 95-5% by weight. When copolymer A is less than 5% by weight and (co)polymer B is more than 95% by weight, or copolymer A is 95% by weight.
If the amount of (co)copolymer B exceeds 5% by weight and the amount of (co)copolymer B is less than 5% by weight, the resulting block copolymer composition will take on the properties of a homo or random (co)polymer and will not be compatible with other resins. The dispersibility and dispersion stability of the block copolymer are significantly lowered, and properties specific to the block copolymer are lost, which is not preferable.

As a method for producing a block copolymer composition, the general formula (
Any method may be used to produce the radical copolymerizable peroxycarbonate represented by (2), as long as it is not decomposed by a catalyst or the like.

Specifically, the anion living method, the sequential addition method, the polymer reaction method, the polymeric peroxide (polymeric azo compound) method, etc. are exemplified, but the most preferred is the polymeric peroxide (polymeric azo compound) method. When producing by this method, care must be taken not to decompose the peroxy group since the 10-hour half-life temperature of the radical copolymerizable peroxycarbonate represented by general formula (I) is 95-105°C. For copolymerization, the polymerization temperature should be 90°C or lower, more preferably 85°C or lower. Further, in that case, any method such as bulk polymerization, suspension polymerization, emulsion polymerization, or solution polymerization may be employed as the polymerization method.

The chemical structure of the copolymer A component in the block copolymer composition of the present invention has an infrared absorption spectrum (characteristic infrared absorption band)
, confirm the presence and amount of peroxycarbonate groups by measuring the amount of active oxygen by iodometry, and clarify the structures of alkyl groups, cycloalkyl groups, and phenyl groups by pyrolysis gas chromatography and nuclear magnetic resonance spectroscopy. By this, the monomer composition can be clarified.

Furthermore, the blocking efficiency of the block copolymer composition can be measured by extraction method, fractional precipitation method, molecular weight,
The molecular weight distribution can be determined by gel permeation chromatography (hereinafter abbreviated as GPC).

(Effects of the Invention) As detailed above, the block copolymer composition of the present invention consists of copolymer A and copolymer B, and copolymer A is an aromatic vinyl copolymer. This is a block copolymer composition characterized in that peroxide bonds are pendantly bonded in the main chain of copolymer A. Therefore, other resins such as olefins such as polyethylene, polypropylene, ethylene-propylene copolymers, ethylene-propylene-diene copolymers, ethylene-(meth)acrylic ester copolymers, ethylene-vinyl ester copolymers, etc. It can be used to modify condensed engineering plastics such as (co)polymers, polyphenylene ethers, polycarbonates, and thermoplastic polyesters, celluloses, and silicone resins.

In this method, the block copolymer composition of the present invention may be dissolved in a monomer during the polymerization or condensation reaction, but
Preferably, when the block copolymer composition of the present invention and another resin are melt-blended in a molding machine such as an extruder, injection molding machine, or kneading machine, a grafting reaction is preferably carried out at the same time. At this time, the melting temperature is preferably 150-300°C.

When the above operations are performed, due to the properties of the block copolymer, the block copolymer composition is uniformly dispersed in the other resin (matrix resin) and localized in the block copolymer composition. As the peroxycarbonate groups in the block copolymer composition decompose, the block copolymer composition is grafted onto the matrix resin, improving the interfacial strength between the matrix resin and the block copolymer composition. The particle size of particles dispersed in the matrix resin also becomes smaller.

Furthermore, since copolymer A is an aromatic vinyl copolymer, it is also expected to improve heat resistance, weather resistance, moldability, and electrical insulation.

As described above, the block copolymer composition of the present invention can be modified without reducing the mechanical properties of the matrix resin.

(Examples, Comparative Examples, and Reference Examples) The present invention will be specifically described below using Examples, Comparative Examples, and Reference Examples.

Example 1 When copolymer A was polymerized, 60% by weight of styrene was used as an aromatic vinyl monomer, 35% by weight of methyl methacrylate was used as a monomer copolymerizable with it, and t- as a radical copolymerizable peroxycarbonate. 5% by weight of butylperoxymethacryloyloxyethyl carbonate was mixed to make 30 parts by weight.

Next, 5 parts by weight of a polymeric peroxide represented by the following formula (% formula %) was added as a polymerization initiator, and after thorough stirring, the mixture was placed in a four-bottle flask equipped with a condenser containing 600 parts by weight of a 1% by weight polyvinyl alcohol aqueous solution with stirring. Suspension polymerization was carried out at a temperature of 60° C. to 80° C. for 5 hours, and when it was confirmed that the polymerization conversion was 95% or more and the polymerization was completed, the polymerization was stopped to obtain copolymer A.

Next, 70 parts by weight of methyl methacrylate as a monomer to become (co)polymer B and 0.2 parts by weight of n-dodecyl mercaptan as a molecular weight regulator were added to the copolymer A, and the polymerization temperature was 70°C. Polymerization was continued at -80°C, and after completion of the polymerization, the polymerized product was filtered, washed with water, and dried to obtain the desired block copolymer composition.

The test results of this block copolymer composition were as follows.

Active oxygen amount 0.088% Number average molecular weight 121.000 Blocking efficiency 45% Polymerization conversion rate 98.5% Active oxygen amount of unblocked methyl methacrylate polymer (co)polymer B) 0.000% As for the test method, the amount of active oxygen was determined by iodometry, the number average molecular weight was determined by GPC measurement, and the blocking efficiency was determined by extracting the unblocked methyl metaphthalate polymer by Soxhlet extractor using cisetonitrile as a solvent. I asked for it. The polymerization conversion rate was calculated by the gravimetric method using the following formula.

The weight of all monomers used, and the heat distortion temperature of this block copolymer composition, J
As a result of measurement in accordance with IS K-7207 method, 110
It was ℃.

Comparative Example 1 In Example 1, 65% by weight of styrene and 35% by weight of methyl methacrylate were used as monomers to form copolymer A.
Example 1 except that t-butylperoxymethacryloyloxyethyl carbonate was not added.
A propulsion copolymer composition was obtained. The test results were: active oxygen amount: o, ooo%, number average molecular weight: 119.000, blocking efficiency: 42%, and polymerization conversion rate: 97.5%.

Example 2-10. Comparative Example 2-5 In Example 1, the type and composition of monomers to be copolymer A and (co)polymer B, the amount of t-butylperoxymethacryloyloxyethyl carbonate, and the amount of copolymer A The blending ratio of (co)polymer B and (co)polymer B was set as in Example 2-7.
The procedure of Example 1 was repeated except for the changes shown in Table 1 for Examples 8-10, Table 2 for Examples 8-10, and Table 3 for Comparative Examples 2-5, and the respective block copolymer compositions were I got something.

The block efficiency was measured by a fractional precipitation method in which the block copolymer composition was dissolved in benzene and then poured into petroleum ether. In addition, when polymerizing (co)polymer B, (
During the polymerization of the co)polymer, n-
Dodecyl mercaptan was used.

In addition, in Tables 1.2 and 3, t-butylperoxymethacryloyloxyethyl carbonate is defined as MBC,
Methyl methacrylate was abbreviated as MMA, n-butyl acrylate as BA, n-butyl methacrylate as BA, styrene as ST, and acrylonitrile as AN.

Table 2 The following can be seen from Tables 1, 2, and 3. That is,
In Comparative Example 2, MEC in copolymer A was 0.1% by weight.
Since the amount of active oxygen in the block copolymer composition is only 0.001% by weight. Moreover, in Comparative Example 3, since 30% by weight of M[EC was added to copolymer A, gelation occurred during polymerization, which is not preferable. In Comparative Examples 4 and 5, the copolymer or copolymer B was
Since it is less than % by weight, when it is made into a solution, it clearly loses its properties as a block copolymer composition.

Example 11 As a result of measuring the decomposition temperature of the block copolymer composition produced in Example 1 using a thermobalance, the decomposition temperature was 225
It was ℃.

Comparative Example 6 In Example 1, vinyl acetate 9 was used as the monomer of copolymer A.
5% by weight, t-butyl peroxyallyl carbonate 5
% by weight, and a block copolymer composition was obtained in accordance with Example 1 except for the following. This block copolymer composition has the following: Active oxygen content: 0.218% Number average molecular weight: 95.000 Blocking efficiency: 68% Polymerization conversion rate: 98.0% Active oxygen content of unblocked styrene copolymer B: o, ooo% The decomposition temperature measured on a thermobalance was 165°C.

Reference Example 1 As the matrix resin, ethylene-vinyl acetate (“Flowback K-2010J manufactured by Steel Chemical Industry Co., Ltd.) 9
10 parts by weight of the block copolymer composition produced in Example 1 was added to 0 parts by weight in a Banbury mixer at 230°C.
The mixture was blended for 10 minutes under melting conditions, and its grafting efficiency, flexural modulus, and elongation were measured.

Incidentally, the grafting efficiency was determined by a fractional precipitation method using a benzene-acetone system.

Grafting efficiency 55% Flexural modulus 370 kg/cm elongation rate
The flexural modulus of 730% flowback K-2010 is 205
kg/cm, and the elongation rate was 795%.

Reference Example 2 In the same manner as in Reference Example 1, 10 parts by weight of Flowback K-201090 as a matrix resin and 10 parts by weight of the block copolymer composition produced in Comparative Example 1 were blended. As a result of measurement in the same manner as in Reference Example 1, graft efficiency: 4% Flexural modulus: 290 kg/cm elongation rate
It was 255%.

Reference Example 3 The block copolymer composition produced in Comparative Example 2 was used, and a grafting reaction was carried out in accordance with Reference Example 1 except for the block copolymer composition. As a result, the grafting efficiency was 11%.

Claims (1)

[Claims] 1. (a) One or more aromatic vinyl monomers 50
-99.4% by weight, 0.1-30% by weight of a monomer copolymerizable with an aromatic vinyl monomer, and 0.1% to 30% by weight of a monomer copolymerizable with an aromatic vinyl monomer, and 0.1% by weight of a radical copolymerizable peroxycarbonate represented by the following general formula (I).
Copolymer A obtained by radical copolymerization of 5-20% by weight of
5-95% by weight, and (b) one or more radical (co)polymerizable monomers, and has the following general formula (I)
A block copolymer composition that does not contain the radically copolymerizable peroxycarbonate represented by the formula and is composed of the copolymer A and 95-5% by weight of a (co)polymer B having a different monomer composition. . The radical copolymerizable peroxycarbonate represented by the above general formula (I) is as follows: ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R_1 represents a hydrogen atom or an alkyl group having 1 to 2 carbon atoms. , R_2 is a hydrogen atom or a methyl group, R_
3 and R_4 each represent an alkyl group having 1-4 carbon atoms,
R_5 represents a group selected from the group consisting of an alkyl group having 1 to 12 carbon atoms, a phenyl group, an alkyl-substituted phenyl group, and a cycloalkyl group having 3 to 12 carbon atoms. n is 1
Indicates an integer between 1 and 2. ) is a compound represented by 2. The block copolymer composition according to claim 1, wherein the amount of active oxygen is 0.002% by weight or more. 3. The radical copolymerizable peroxycarbonate represented by the general formula (I) is t-butylperoxymethacryloyloxyethyl carbonate, according to either claim 1 or 2. block copolymer composition. 4. The block copolymer according to any one of claims 1 to 2, wherein at least one of the aromatic vinyl monomers used in copolymer A is styrene. Coalescing composition. 5. Claims 1 to 5, characterized in that copolymer B is formed by polymerizing monomers containing at least 50% by weight of one or two (meth)acrylic acid ester monomers. The block copolymer composition according to any one of Item 2.