JP2542147B2 - Polyamide resin composition with excellent impact resistance - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention contains a polyamide resin, a thermoplastic elastomer and a graft copolymer of a polyamide and a thermoplastic elastomer, and has a number average particle diameter of the elastomer component within a specific range. It relates to a polyamide composition having particularly excellent impact properties.

[0002]

2. Description of the Related Art Conventionally, in applications such as fibers, films, sheets and molded articles made of a polymeric substance, using a single polymeric substance is not enough for the purpose of the product. In cases where it is sufficient, many attempts have been made to give a composition having a large number of components or a laminate to have sufficient strength, improve processability, and reduce the cost of the product. . However, when a polymer material is mixed to form a composition, there are not many combinations of different types having good compatibility.

A mixed composition of different polymeric substances having poor compatibility may not be easily modified by mixing due to inhomogeneity due to poor mixing property, peeling between different phases, and the like. It was It is well known that a styrene-butadiene block copolymer, a styrene-isoprene block copolymer and the like are used as one component for mixing a polymer substance to obtain a composition having excellent properties ( For example, JP-A-50-119055 and JP-A-50-
148457, JP-A-52-117940 and JP-A-52-150457).

However, unmodified block copolymers to which unsaturated carboxylic acids or their derivatives have not been added, polyamide resins such as EPM (ethylene-propylene rubber), EPDM (ethylene-propylene-diene rubber), polyethylene and polypropylene. In the case of the modification of (2), the compatibility between the two is extremely poor, and it is the current situation that a useful mixed composition cannot be obtained.

It is also known to modify polyamide resins by grafting and adding compounds such as maleic anhydride to such copolymers and other elastomers and resins in order to increase compatibility (for example, Japanese Examiner Sho 63
-44784, JP-A-59-56451). Modification of the polyamide resin with these modified block copolymer, modified EPM (ethylene-propylene rubber), modified EPDM (ethylene-propylene-diene rubber), modified polyethylene, modified polypropylene, etc. is considered to improve compatibility with the resin. Therefore, it is said that there is a modifying effect. Japanese Patent Application Laid-Open No. 59-56451 discloses a composition of a polyamide resin, a maleic anhydride-modified partially hydrogenated block copolymer, and a partially hydrogenated polybutadiene (maleic acid is "ene-reacted" with residual double bonds in the main chain). It is described that a graft copolymer of polyamide and the block copolymer is formed by the heat addition) and that it is an essential component. However, the disclosure relates to the dispersed particle size of the elastomer component in the polyamide matrix. In addition to the above, the impact strength of the example with the hydrogenated block copolymer is about 9 kg.
cm / cm is not enough.

Further, in the detailed description of the invention of Japanese Patent Publication No. 63-44784, there is a description about the graft copolymer of the hydrogenated block copolymer and the polyamide, but the ratio of the graft copolymer and the dispersed particle diameter. I haven't touched on it specifically. Japanese Examined Patent Publication No. 55-44108 and Polymer, 26 , November P. 1
855-1863 (1985) describes the particle size by modifying a polyamide resin with an acid-modified elastomer, but discloses the presence and ratio of a modified block copolymer and a specific graft copolymer with a polyamide. There is no.

Therefore, in the prior art, since the elastomer-dispersed particle size, the graft ratio, and the amount of the graft body are not strictly controlled, the modification effect (for example, impact resistance) of the polyamide resin is not sufficient, and it is industrially impossible. At present, it is impossible to obtain a polyamide resin composition having stable quality.

[0008]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention
As a result of diligent studies to improve JP-A-3-44784, a polyamide resin, a styrene-saturated thermoplastic elastomer / polyamide graft copolymer (hereinafter, elastomer-grafted polyamide) having a specific amount of polyamide content, and a heat It has been found that a polyamide composition containing a specific amount of a plastic elastomer and having a maximum average particle diameter of an elastomer component in a specific range is particularly excellent in the balance of flexural modulus and impact resistance, and has already applied for a patent. (Japanese Patent Application No. 3-122986). However, in this method, although the impact strength is excellent, the elastomer-dispersed particle size is easily affected by the processing conditions (particularly the shear rate), and it is necessary to appropriately control the processing conditions in order to obtain an appropriate particle size.

An object of the present invention is to provide a polyamide resin composition which is stable and is not significantly affected by processing conditions and exhibits excellent impact resistance.

[0010]

Means for Solving the Problems As a result of further diligent studies, the present inventors have found that by adding a specific amount of a specific elastomer to the system of Japanese Patent Application No. 3-122986, a stable condition can be obtained regardless of processing conditions. The inventors have found that the above-mentioned impact resistance can be obtained and have reached the present invention. That is, the present invention is
(A) Polyamide resin 10 to 85% by weight, (b) At least two vinyl aromatic compound blocks A and at least one olefin compound polymer block B having an unsaturation degree of not more than 20%, and vinyl aromatic compounds. A graft copolymer (elastomer) in which a polyamide is grafted to a block copolymer having a compound content of 10 to 90% by weight.
Grafted polyamide) 10-55% by weight, (c) thermoplastic elastomer-5-40% by weight, and (d) at least two vinyl aromatic compound blocks A and at least one unsaturated degree not exceeding 20%. It is composed of olefin compound polymer block B and has a vinyl aromatic compound content of 1
Modified block copolymer component in which an unsaturated carboxylic acid or a derivative thereof is bonded to 0.05 to 3 parts by weight per 100 parts by weight of the block copolymer in an amount of 0 to 90% by weight, and a modified block copolymer component 0 to 30% by weight. A composition comprising: (where (a) + (b) + (c) + (d) = 100%),
The polyamide component in the elastomer-grafted polyamide of (b) is 10 to 70% by weight, and the polyamide component in the total of the elastomer in the elastomer-grafted polyamide and the elastomers of (c) and (d) is (c). And the proportion of the elastomer (d) (non-graft elastomer) is 35 to 35.
85% by weight, and the number average particle diameter (d _n ) of the elastomer component in the polyamide resin composition is 0.1 ≦ d _n ≦
(1.39353 × 10 ⁻⁴ ) × E ³ − (3.56763)
× 10 ^-3 ) × E ² + (3.89005 × 10 ^-2 ) × E
+0.05 μm (where E represents the weight% of the net elastomer component in the total composition) and relates to a polyamide resin composition having excellent impact resistance.

Hereinafter, the present invention will be described in detail. The (a) polyamide resin, which is one component of the present invention, contains repeating aromatic and / or aliphatic amide groups throughout the polymer backbone and generally comprises a condensation product known as "nylon". means. These are obtained by polymerizing a monoaminocarboxylic acid having at least two carbon atoms between an amino group and a carboxyl group or an internal lactam thereof, or a diamine and a dicarboxylic acid having a carbon number between the amino groups of at least 2. Can be prepared by polymerizing in equimolar proportions, or by polymerizing the monoaminocarboxylic acid or its internal lactam as described above with substantially equimolar proportions of diamine and dicarboxylic acid. The dicarboxylic acids may be used in the form of their functional derivatives, for example esters.

The term "substantially equimolar ratio" as used herein includes both a strict equimolar ratio and a ratio slightly deviated from the ratio contained in a usual technique for stabilizing the viscosity of the obtained polyamide. used. Examples of the monoaminocarboxylic acid or a lactam thereof include a compound having a carbon number of 2 to 16 between an amino group and a carboxyl group and forming a ring with a -CO-NH- group when the carbon atom is a lactam. Can be mentioned. Specific examples of aminocarboxylic acids and lactams include ε-aminocaproic acid, butyrolactam, vivarolactam, caprolactam, enanthlactam, undecanolactam, dodecanolactam and the like.

Examples of said diamines have the general formula H ₂ N (C
H _{2) n} NH ₂ (wherein, n is 2-16 integer.)
And examples thereof include trimethylenediamine, tetramethylenediamine, pentamethylenediamine, octamethylenediamine, decamethylenediamine, dodecamethylenediamine, and hexadecamethylenediamine.
Alkylated diamines such as 2,2-dimethylpentamethylenediamine, 2,2,4- and 2,4,4-trimethylhexamethylenediamine are further examples. Examples of other diamines include aromatic diamines such as p
-Phenylenediamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone,
4,4'-diaminodiphenylmethane, m-xylenediamine and p-xylenediamine can be mentioned. Examples of the alicyclic diamine include diaminodicyclohexylmethane.

The dicarboxylic acid may be aromatic, such as isophthalic acid and terephthalic acid. Suitable dicarboxylic acids are of the formula HOOCYCOOH, where Y represents a divalent aliphatic group having at least 2 carbon atoms, examples of such acids are sebacic acid, octadecandioic acid, Suberic acid, azelaic acid, undecanedioic acid, glutaric acid, pimelic acid, adipic acid and the like.

Examples of polyamides that can be incorporated into the polymer composition of the present invention include: Nylon 66, Nylon 4, Nylon 46, Nylon 6, Nylon 7, Nylon 8, Nylon 9, Nylon 11, Nylon 12, Nylon 69, Nylon 610, Nylon 612, Nylon 1
212 and other nylon copolymers such as nylon 6
Nylon 66 copolymer, nylon 6-nylon 12 copolymer, aromatic nylon (nylon 6T, nylon 6I /
6T, nylon MXD6) and the like.

Examples of suitable nylons include nylon 6, nylon 66, nylon 11 and nylon 12. The number average molecular weight of the polyamide used in the present invention is 2
00-50000, preferably 7000-30000
And has a melting point of 150 to 270 ° C.
If the composition of the present invention is required to have excellent processability, 26
Polyamides having a melting point below 0 ° C. are preferred.

The amount of charged polyamide included in the present invention may range from about 50 to about 90% by weight, based on the total weight of the composition. The preferred amount of polyamide is 70-85% by weight. These amounts positively affect the impact resistance and elastic modulus of the final composition. The elastomer-grafted polyamide (b), which is the second component of the present invention, is obtained by reacting the above-mentioned polyamide with a modified styrene-saturated thermoplastic elastomer (hereinafter abbreviated as modified hydrogenated block copolymer). It is a graft polymer. The modified hydrogenated block copolymer constituting the elastomer-grafted polyamide and the modified block copolymer (d) are at least two vinyl aromatic compound blocks A and at least one olefin having an unsaturation degree not exceeding 20%. It is composed of the compound polymer block B and has a vinyl aromatic compound content of 10 to 9
Modified hydrogenation in which a molecular unit containing a carboxylic acid, an acid anhydride group or a derivative group thereof is bonded to 0 to 0% by weight of a hydrogenated block copolymer in an amount of 0.05 to 3 parts by weight per 100 parts by weight of the block copolymer. It is a block copolymer.

The above block copolymer before modification and hydrogenation contains at least two vinyl aromatic compound polymer blocks and at least one polymer block mainly composed of a conjugated diene compound. Here, the polymer block mainly composed of a conjugated diene has a weight ratio of the vinyl aromatic compound to the conjugated diene compound of from 0/100 to 50 /.
It is a polymer block having a composition range of 50, preferably 0/100 to 40/60, and the distribution of the vinyl aromatic compound in this block is random, taper (monomer component increases along the molecular chain). Or decrease),
It may be partially block-shaped or any combination thereof. In the block copolymer before hydrogenation in the present invention, 50% by weight of the vinyl aromatic compound is present in the transition part between the vinyl aromatic compound polymer block and the polymer block mainly containing the conjugated diene compound. Although a copolymer portion of the vinyl aromatic compound and the conjugated diene compound exceeding the above may exist, such a polymer portion is included in the polymer block mainly containing the conjugated diene compound.

In the above block copolymer, the weight ratio of the content of the vinyl aromatic compound to the content of the conjugated diene compound is 10/90 to 90/10, and 20/80 to 8
A range of 5/15 is preferred. As the vinyl aromatic compound constituting the block copolymer before hydrogenation, one kind or two or more kinds are selected from styrene, α-methylstyrene, p-methylstyrene and the like, and styrene is particularly preferable. preferable. The conjugated diene compound is selected from butadiene, isoprene, 1,3-pentadiene and the like, and is used alone or in combination of two or more.
Or isoprene is particularly preferred. The block copolymer has a number average molecular weight of 20,000 to 500,000, and a molecular weight distribution (ratio of weight average molecular weight to number average molecular weight) of 1.05 to 10 is preferable. The molecular structure of the block copolymer may be linear, branched, radial, or a combination thereof. Furthermore, when butadiene is used as the conjugated diene compound in the block copolymer, 1,2 of the microstructure of the butadiene part
The amount of binding is preferably in the range of 10 to 80%. When the modified block copolymer is required to have rubber elasticity, the 1,2 bond content is particularly preferably in the range of 25 to 55%.

When the block copolymer contains two or more blocks mainly containing a vinyl aromatic compound, the blocks may have the same structure, the content of the monomer component, and the molecules thereof. Each structure such as distribution in chain, molecular weight of block, and microstructure may be different. The above block copolymer is usually benzene,
It can be obtained by living anion polymerization of a vinyl aromatic compound and a conjugated diene compound in an inert hydrocarbon solvent such as toluene, hexane or cyclohexane using an organolithium compound such as butyllithium as a catalyst. Further, the block copolymer having a lithium active terminal obtained by the above method is subjected to a coupling reaction with a polyfunctional coupling agent, for example, carbon tetrachloride, silicon tetrachloride or the like, to obtain a branched or radial block copolymer. It is also possible. Further, the block copolymer can be used not only as one kind but also as a mixture of two or more kinds.

By hydrogenating the above block copolymer by a known method, for example, the method described in Japanese Patent Publication No. 9041-9043, the aromatic double bond of the vinyl aromatic compound block A is substantially converted. Hydrogenated block copolymers can be synthesized in which at least 80% of the carbon / carbon unsaturated double bonds of the conjugated diene are hydrogenated without hydrogenation. An example of modifying the hydrogenated block copolymer with an unsaturated carboxylic acid or a derivative thereof is shown below.

When the block copolymer to be modified does not have carbon / carbon unsaturated double bonds at all or the degree of unsaturation is 10% or less, preferably 3% or less, when it is modified with the compound described later, It is obtained by adding a commonly used radical initiator in the coexistence. The method for producing these modified elastomers is not particularly limited in the present invention, but the obtained modified elastomer contains undesired components such as gel, and its melt viscosity is remarkably increased to deteriorate the processability. The manufacturing method is not preferable. A preferable production method is, for example, a method of reacting an unmodified hydrogenated block copolymer with an unsaturated carboxylic acid or a derivative thereof in the presence of a radical initiator in an extruder. Further, a method in which an unmodified hydrogenated block copolymer is dissolved in a solvent and reacted with an unsaturated carboxylic acid or a derivative thereof in the presence of a radical initiator is also used.

When the hydrogenated block copolymer to be modified contains a large amount of carbon / carbon unsaturated double bonds in its molecule or when the degree of unsaturation exceeds 10%, the above method is remarkably used. This is not preferable because it causes gelation and deteriorates the physical properties of the final composition and the processability. In such a case, the modified elastomer is produced by heating and mixing the hydrogenated block copolymer and the unsaturated carboxylic acid or its derivative to "ene-react" with the carbon / carbon unsaturated double bond. If necessary, a stabilizer or the like may coexist to prevent gelation due to heat.

Examples of the unsaturated carboxylic acid or its derivative used for modifying the hydrogenated block copolymer include maleic acid, maleic acid ester, maleic acid amide, maleic acid imide, maleic anhydride, fumaric acid, fumaric acid ester, Fumaric acid amide, fumaric acid imide, phthalic acid, itaconic acid, itaconic anhydride, itaconic acid ester, itaconic acid amide, itaconic acid imide, halogenated maleic acid, halogenated maleic acid ester, halogenated maleic acid amide, halogenated maleic acid Acid imide, acrylic acid, crotonic acid, methacrylic acid, cis-4-cyclohexane-1,2-dicarboxylic acid, its anhydride, its ester, its amide, and its imide, endo-cis-bicyclo (2,2,1 ) -5-Heptene-2,3-dicarboxylic acid, its anhydride, its Ester, its amide, and its imide, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic acid amide Etc., but maleic anhydride and glycidyl (meth) acrylate are particularly preferable.

The amount of unsaturated carboxylic acid or its derivative added to the hydrogenated block copolymer is 0.05 to 3 parts by weight per 100 parts by weight of the hydrogenated block copolymer, and 0.0
It is preferably 8 to 2.5 parts by weight. When the amount of addition is less than 0.05 parts by weight, the composition will not be a compatibilizer for the polyamide resin and the elastomer component because the amount of the elastomer-grafted polyamide formed will be too small, as will be described later. There is almost no quality effect.

When the addition amount exceeds 3 parts by weight, the amount of the elastomer-grafted polyamide produced is in a suitable range (the amount of the elastomer-grafted polyamide in the entire composition is 10 to 10).
55% by weight) or an elastomer that forms.
Since the content of the polyamide component in the graft polyamide exceeds the preferred range (10 to 70% by weight of the polyamide component in the elastomer-grafted polyamide), the elastomer component is too finely dispersed in the polyamide matrix, resulting in an elastomer number average particle. The diameter (d _n ) is 0.1 ≦ d _n ≦ (1.
39353 x 10 ^-4 x E ^3- (3.56763 x 1
0 ^-3 ) × E ² + (3.89005 × 10 ^-2 ) × E +
0.05 μm (however, E represents the weight% of the net elastomer component in the total composition) or the particle size control becomes difficult, which is not preferable.

The "elastomer component" forming the number average particle size means the elastomer-grafted polyamide (b), the thermoplastic elastomer (c) and the modified block copolymer (d). The number average particle diameter E for use in expression for defining the (d _n), i.e. the weight percent of the elastomer component a net in the total composition, elastomer (b) - the elastomeric portion of the graft in the polyamide,
Proportion (% by weight) of the total amount of the thermoplastic elastomer of (c) and the modified block copolymer of (d) in the total composition.
Represents For example, when this composition is prepared from a polyamide, a thermoplastic elastomer, and a modified hydrogenated block copolymer, the total weight% of the charged thermoplastic elastomer and the modified hydrogenated block copolymer is .

The unsaturated carboxylic acid or its derivative used in the present invention can be used not only in one kind but also in a mixture of two or more kinds. Third component (c) thermoplastic elastomer
Examples of the non-modified hydrogenated block copolymer include elastomers containing carbon / carbon unsaturated double bonds such as natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR) and styrene butadiene rubber (SBR). Or its (partial) hydrogenated product, ethylene propylene rubber (EPM) ethylene propylene diene rubber (EPDM), butyl rubber (I
IR) and other olefinic rubbers, and block copolymers of conjugated diene compounds and vinyl aromatic compounds. Preferably unmodified hydrogenated block copolymer, E
Thermoplastic elastomers containing no or almost no carbon / carbon unsaturated double bonds such as PM and EPDM are used.

The thermoplastic elastomer (c) may be a mixture of two or more kinds. The weight average molecular weight of the thermoplastic elastomer as the component (c) is 5,000 to 500.
000, and particularly 10,000 to 200,000 is preferably used from the viewpoint of workability. It is the fourth component (d)
The modified hydrogenated block copolymer of (b) is an elastomer.
It is a modified hydrogenated block copolymer that does not react with the polyamide constituting the grafted polyamide.

These (c) component thermoplastic elastomers, (d) component modified hydrogenated block copolymers and (b)
The proportion of the hydrogenated block copolymer component in the elastomer-grafted polyamide constituting the component is such that the elastomer (bonded with the polyamide) in the elastomer-grafted polyamide to be formed and the thermoplastic elastomer (c) ( The proportion (c) + (d) (non-graft elastomer) in the total of the modified hydrogenated block copolymer of d) is selected to be 35 to 85% by weight.

Depending on the amount of the polyamide component in the elastomer-grafted polyamide and the processing conditions, if the amount is less than 35% by weight, the number average particle size tends to be small, which is not preferable for developing the impact strength. On the other hand, if it exceeds 85% by weight, the number average particle diameter tends to increase, which is outside the preferable particle diameter range, which is not preferable. In addition,
The amounts of the non-graft elastomers of (c) and (d) are not the charged amount but the analytical value obtained by the solvent composition fractionation method.

The composition of the present invention uses a hydrogenated block copolymer modified with an unsaturated carboxylic acid or a derivative thereof so that its functional groups and terminal functional groups (carboxyl group and amino group) of the polyamide resin or main Reacting with the amide group (-CO-NH-) in the chain to form an elastomer-grafted polyamide having a specific amount of polyamide,
This ungrafted elastomer and polyamide - a suitable amount present in the total composition is a compatibilizer for and elastomer - number-average particle diameter of component (d _n) is 0.1 ≦ d _n ≦ (1.39
353 × 10 ⁻⁴ ) × E ³ − (3.56763 × 10 ⁻³ ).
× E ² + (3.89005 × 10 ^-2 ) × E + 0.05μ
m (however, E represents the weight% of the net elastomer component in the total composition) so that the compatibility between the polyamide and the elastomer is moderately improved by appropriately controlling the processing conditions. unmodified elastomer - or elastomer having a polyamide amount deviating from the specified amount - elastomer having a polyamide content of the graft polyamide or a specific amount - the number-average particle diameter in the amount of the graft polyamide deviates from a suitable range (d _n) 0 1 ≦ d _n ≦
(1.39353 × 10 ⁻⁴ ) × E ³ − (3.5676
3 × 10 ^-3 ) × E ² + (3.89005 × 10 ^-2 ) × E
+0.05 .mu.m (where E represents the weight% of the net elastomer component in the total composition), and the physical properties of the composition are remarkably improved as compared with the case where it cannot be controlled. .

That is, even if the number average particle diameter of the elastomer component in the polyamide resin matrix is too large, [(1.39353 × 10 ⁻⁴ ) × E ³ − (3.5676)
3 × 10 ^-3 ) × E ² + (3.89005 × 10 ^-2 ) × E
+0.05 (provided that E represents the weight% of the net elastomer component in the total composition) μm>, but if it is too small (less than 0.1 μm), the impact strength is not In order to control the number average particle size within this range, the elastomer-grafted polyamide having a polyamide amount of 10 to 70% by weight is present in the entire composition in an amount of 10 to 55% by weight, and is not grafted. Elastomer
It is essential that the (non-graft elastomer) is contained in an amount of 35 to 85% by weight in all the elastomer components in order to exhibit particularly excellent impact strength.

The modified hydrogenated block copolymer (d) means an unreacted modified hydrogenated block copolymer which does not react with the polyamide. Therefore, when the modification amount is relatively large or the reactivity with the polyamide is extremely high, this amount becomes substantially zero. The suitable amount of (d) is 0 to 30% by weight. If this amount exceeds 30% by weight, there is a balance with (c), but impact resistance may depend on processing conditions, which is not preferable in some cases. More preferably 0 to 1
0% by weight.

The presence and amount of the elastomer-grafted polyamide are confirmed by fractionation and analysis by a solvent composition fractionation method using a mixed solvent as described later. The elastomer-grafted polyamide is 10-55% in the total composition.
The physical properties of the composition are improved when the composition is contained in a weight percentage. That is, when the amount of the elastomer-grafted polyamide is less than 10% by weight of the total composition, the processing conditions (extruder temperature, screw pattern, screw rotation speed, modification amount).
Even if is changed, the number average particle size of the elastomer is (1.39
353 × 10 ⁻⁴ ) × E ³ − (3.56763 × 10 ⁻³ ).
× E ² + (3.89005 × 10 ^-2 ) × E + 0.05
(However, E represents the weight% of the net elastomer component in the entire composition.) Since it is not less than μm, good physical properties cannot be obtained. If the amount of the elastomer-grafted polyamide exceeds 55% by weight of the total composition, the number average particle diameter (d _n ) of the elastomer will be less than 0.1 μm even if the processing conditions are changed.
Alternatively, 0.1 ≦ d _n ≦ (1.39353 × 10 ⁻⁴ ) ×
^{E 3 - (3.56763 × 10 -3} ) × E 2 + (3.89
005 × 10 ⁻² ) × E + 0.05 μm, where E represents the weight percent of the net elastomer component in the total composition and is difficult to control. Optimally, the elastomer-grafted polyamide is optimally contained in the total composition in an amount of 15 to 50% by weight.

The reason why the impact strength decreases when the particle size becomes too small (compatibility is too good) is not clear.
It is considered that the contribution of crazing becomes large like the mechanism of destruction of IPS (high impact polystyrene). It is essential that the content of the polyamide component in the elastomer-grafted polyamide is 10 to 70% by weight. Elastomer and this amount is less than 10 wt% - amount of graft polyamides number average particle diameter be within the range given above the _{(d n) (1.39353 × 10} -4) × E 3 -
(3.56763 × 10 ⁻³ ) × E ² + (3.89005
X10 ^-2 ) x E + 0.05 μm (where E represents the weight% of the net elastomer component in the total composition) and it is difficult to make it below. Also the amount is 70 wt Pas - exceeds cent tends to a particle size too small, practically the number average particle diameter (d _n) of 0.1 ≦ d _n ≦ (1.39353
× 10 ^-4 ) × E ³ − (3.56763 × 10 ⁻³ ) × E ²
+ (3.89005 × 10 ^-2 ) × E + 0.05 (however,
E represents the weight% of the net elastomer component in the total composition) and is difficult to control in the μm range. The amount of polyamide component in the preferred elastomer-grafted polyamide is 15-55% by weight.

This elastomer-grafted polyamide is prepared by reacting a polyamide and a modified hydrogenated block copolymer in advance by an appropriate method, blending it with a polyamide resin and a thermoplastic elastomer in an appropriate ratio, and using a usual polymer substance. It can be prepared by an apparatus used for mixing. Examples of the mixing device include an extruder, a mixing ball, a Banbury mixer, and a kneader, and a melt mixing method using an extruder is particularly preferable.

Alternatively, the elastomer-grafted polyamide can be manufactured at once in the process of manufacturing the composition. That is, the modified hydrogenated block copolymer, the polyamide resin, and the thermoplastic elastomer are blended together and melt-mixed at the melting point of the polyamide or higher in the above apparatus, and this method is preferable. In order to make the amount of the elastomer-grafted polyamide within a suitable range, it is necessary to properly select the modification amount of the modified hydrogenated block copolymer and the kind of the modifying agent. That is, it is preferable that the amount is 0.05 to 3 parts by weight per 100 parts by weight of the hydrogenated block copolymer component for modifying the unsaturated carboxylic acid or its derivative, as described above. If there is any, the graft body is formed appropriately by appropriately selecting the processing conditions.

In the case of melt mixing using an extruder, the extrusion temperature and residence time can be changed depending on the composition of the mixture and the desired graft ratio. That is, the temperature is 12
It may range from 0 to 320 ° C. and the residence time is from 10 seconds to
It may be in the range of 150 minutes. When the amount of modification is relatively large, it is preferable to set the processing conditions in a mild direction.
For example, when melt mixing with an extruder, methods such as lowering the screw rotation speed, lowering the extrusion temperature, and shortening the residence time are usually adopted. On the contrary, when the amount of modification is relatively small, the opposite method is used.

If the amount of unsaturated carboxylic acid or its derivative added exceeds 3 parts by weight per 100 parts by weight of the hydrogenated block copolymer component to be modified, or if the amount of modification is comparatively large, then (c) It is necessary to add a relatively large amount of thermoplastic elastomer component to achieve a suitable amount of elastomer-grafted polyamide. The thermoplastic elastomer used as the component (c) may be the same as or different from the hydrogenated block copolymer before being modified. Two or more types of elastomers may be used as the component (c). In order to achieve a suitable range of the elastomer-grafted polyamide, the processing conditions are changed to control the amount (reaction rate), the modification amount and the kind of the modifier are changed, or the heat of the component (c) is changed. Whether to control by changing the amount of the plastic elastomer is appropriately selected and is not particularly limited. An appropriate amount of (c) added is 5 to 40% by weight. This amount is 5% by weight
If it is smaller, the particle size tends to be smaller.
When the content is more than 10% by weight, the particle size is less likely to be affected by the processing conditions, but the particle size tends to increase and deviates from the optimum particle size, which is not preferable.

The composition thus obtained is quenched with water, cut into pellets or powder or crushed, and then subjected to an Izod impact test by injection molding. In addition, the polyamide composition of the present invention is a reinforcing agent or filler such as calcium carbonate, silica, carbon black, glass fiber, clay, process oil, polyethylene glycol, phthalate, etc. to the extent that the composition is not impaired. It is also possible to add plasticizers such as acid esters. Further, other additives such as a heat stabilizer, an antioxidant, an ultraviolet absorber, a colorant and a pigment may be added, and a foaming agent is further added to the composition of the present invention to form a foam. Is also possible.

As already mentioned, during the melt mixing, an elastomer-grafted polyamide is partially produced from the polyamide and the hydrogenated block copolymer modified with the unsaturated carboxylic acid or its derivative. When the modification is maleic anhydride, the pendant succinic anhydride group (an acid anhydride group, which may be partially or fully ring-opened) of the maleic anhydride adduct is a polyamide under appropriate temperature and time conditions. It is believed that the elastomeric grafted polyamide containing amide or imide bonds reacts with the terminal amino groups of the resin (and reacts with amide groups under some conditions) to form a certain amount. When the modification is glycidyl methacrylate, the epoxy group of the pendant glycidyl methacrylate group reacts with the terminal carboxyl group of the polyamide resin under appropriate temperature and time conditions, etc. It is believed that the reaction) forms ester groups and that the elastomer-grafted polyamide is produced in a certain amount.

In order to accelerate this graft reaction, an appropriate amount of a catalyst or promoter such as an acid or a base may be added, or when the elimination of low molecular weight is accompanied by the reaction, the system may be depressurized or vacuumed.

[0044]

EXAMPLES The following examples are given to illustrate the present invention more specifically and are not intended to limit the scope of the present invention. The obtained elastomer-grafted polyamide is a solvent composition fractionation method [J. Polymer
Science, Polymer Chemistry
Edition, 12 P. 2613-2622 (19
74)) and analyzed for its amount, the polyamide content in the elastomer-grafted polyamide and the amount of free (non-grafted) elastomer.

In this method 1.50 g of the composition is dissolved in 30 ml of m-cresol. The solution obtained is then diluted with 120 ml of cyclohexane. The resulting solution is then centrifuged to yield a large amount of clear upper and lower layers. The upper layer was decanted off and then 1000m
Coagulate in 1 liter of methanol, filter with a Teflon membrane filter, wash with a large amount of methanol, dry and weigh. From this fraction, 4 in toluene
Free elastomer is obtained by refluxing for 8 hours. Next, 150 ml of 81/19 cyclohexane / m-cresol mixture is added to the lower layer solution and dissolved. Similarly, centrifugation and decantation are repeated to obtain a second fraction. The next fraction is 80
/ 20, 79.5 / 20.5, 79/21, 77/23
Obtained with a cyclohexane / m-cresol mixed solvent. All fractions are agglomerated by adding in a large amount of methanol, washed with methanol, dried and weighed.

In the following reference example, the existence of the graft will be clarified by the solvent composition fractionation method by the core survey method. Reference Example Solvent composition fractionation was carried out for the system of Example 2 (hydrogenated styrene / butadiene block polymer (H-1051) = 80/20 modified with nylon 6 / maleic anhydride 1.13 parts by weight). The results obtained are shown in Table 1.

From Table 1, it is considered that the graft body is contained in the B, C and D components, and the other composition fractions have the same tendency. Therefore, the sum of these amounts will be referred to as an elastomer-grafted polyamide hereinafter. The number average particle size of the elastomer component in the polyamide matrix is determined by scanning electron microscope (SEM).
It was measured by [S-800 manufactured by Hitachi, Ltd.]. First, the Izod impact test piece is mirror-finished under cooling using a cryomicrotome, and then etched with reflux toluene. This is subjected to SEM measurement by a conventional method, and the elastomer particle size is observed at 500 to 8000 times. The number average particle diameter was determined using an image analyzer [Image Analysis System IP-1000, manufactured by Asahi Kasei Co., Ltd.].

Here, the number average particle diameter (d _n ) is defined as follows. d _n = Σn _i d _i / Σn _i (where n _i is the particle size d
The number of particles that are _i ) The polyamide content in the elastomer-grafted polyamide is the total nitrogen analyzer [trade name, T, manufactured by Mitsubishi Kasei Co., Ltd.].
N-10].

The molecular weight of the elastomer component is GPC
[Measured by Shimadzu Corporation, LC-3A],
The microstructure of the butadiene portion of the butadiene / styrene block copolymer is FT-IR [FT, manufactured by JASCO Corporation, FT
-IR 5000] was obtained by the Hampton method.
Further, the hydrogenation rate was ¹ H-NMR in a CDCl ₃ solution [FT-NMR GX-270, 270M manufactured by JEOL Ltd.].
Hz].

The amount of added maleic acid was determined by titration with sodium methylate, and the amount of added glycidyl methacrylate was
^It was determined by quantifying the proton of the glycidyl group by ¹ H-NMR or by potentiometric titration of the epoxy group with (C ₂ H ₄ ) ₂ NBr-HClO ₄ . The following polymers (polyamide resin, elastomer) were synthesized or used as they were, and dried sufficiently before use.

[Polyamide Resin] (1) Nylon 6 Amylan (trademark) manufactured by Toray Industries, Inc.
CM-1017 (2) Nylon 66 Reona (trademark) manufactured by Asahi Kasei Corporation
1300S (3) Nylon 12 Daicel Co., Ltd. Daiamide (trademark) L1940 [Elastomer] (1) EPM A polymer: Nippon Synthetic Rubber Co., Ltd. EP11 [ML
_{1 + 4} (100 ° C.) = 40] (2) EPDM B polymer: EP24 [ML manufactured by Nippon Synthetic Rubber Co., Ltd.
_{1 + 4} (100 ° C.) = 65, iodination = 15) (3) Hydrogenated styrene / butadiene block copolymer C polymer: Asahi Kasei Co., Ltd. H-1031 D polymer: Asahi Kasei Co., Ltd. H-1041 E Polymer: Asahi Kasei Co., Ltd. H-1051 F Polymer: Asahi Kasei Co., Ltd. H-1071 KG Polymer: Shell Chemical Clayton G-16
52 (4) Styrene / butadiene block copolymer (Synthesis example 1) By subjecting butadiene and styrene to living anion block polymerization using THF as a vinyl modifier in cyclohexane solvent using n-butyllithium as a polymerization solvent, A block copolymer was synthesized.

I polymer: SBS, styrene amount = 30% by weight, vinyl amount = 38% by weight, number average molecular weight = 5800
0 (5) Partially Hydrogenated Styrene / Butadiene Block Copolymer (Synthesis Example 2) The above I polymer was used as a catalyst in cyclohexane solvent using cyclopentadienyl titanium dichloride / n-butyllithium, and hydrogen pressure was 7 kg / cm ² , It was hydrogenated at a temperature of 50 ° C. for a predetermined time. The amount of absorbed hydrogen was estimated from the amount of decrease in the pressure of the hydrogen cylinder, and the supply of hydrogen was stopped during each process to stop the reaction. The analytical values of the obtained polymer were as follows.

I'polymer: hydrogenation rate = 75%, same as the following structure I polymer I ″ polymer: hydrogenation rate = 83%, same as the following structure I polymer (6) Maleic acid-modified hydrogenated block copolymer Preparation Part 1 (Synthesis Example 3) Each of the above C, D, E, F and KG elastomers is 1
2.5 parts by weight of maleic anhydride to 100 parts by weight,
0.1 parts by weight of Perhexa 25B (manufactured by NOF CORPORATION)
[Product name] is uniformly dry blended, and then screw type extruder (double screw, screw diameter 30 m under nitrogen atmosphere)
m, L / D = 24, with a vent), and a maleation reaction was carried out at a cylinder temperature of 250 ° C. Unreacted maleic anhydride was further removed from the obtained modified block copolymer by heating under vacuum. The following results were obtained by analyzing this modified block copolymer.

M (C) Polymer: Maleic anhydride modified product of C polymer (addition amount 1.26 parts by weight) M (D1) Polymer: Maleic anhydride modified product of D polymer (addition amount 1.43 parts by weight) M (E) Polymer: Maleic anhydride-modified product of E polymer (addition amount: 1.13 parts by weight) M (F) Polymer: Maleic anhydride modified product of F polymer (addition amount: 1.23 parts by weight) M (KG) Polymer : Maleic anhydride-modified KG polymer (addition amount: 0.92 parts by weight) (7) Preparation of maleic acid-modified hydrogenated block copolymer, Part 2 (Synthesis Example 4) 100 parts by weight of each of the elastomers of D above 1.0, 0.3, 0.1 parts by weight of maleic anhydride and 0.05, 0.03, 0.01 parts by weight of Perhexa 25B (manufactured by NOF Corporation) were added. Then, the same procedure as in Synthesis Example 3 was performed.

When the modified block copolymer was analyzed, the following results were obtained. M (D2) polymer: D-polymer modified with maleic anhydride (addition amount 0.75 parts by weight) M (D3) Polymer: D-polymer modified with maleic anhydride (addition amount 0.24 parts by weight) M (D4) Polymer: Maleic anhydride modified product of D polymer (addition amount 0.02 parts by weight) (8) Preparation of glycidyl methacrylate modified block copolymer (Synthesis Example 5) 100 parts by weight of the above D elastomer. On the other hand, 6.0, 4.0, 2.0, 0.2 parts by weight of glycidyl methacrylate and 0.9, 0.6, 0.3, respectively.
0.03 parts by weight of Perhexin 25B [NOF CORPORATION]
Was added, and a glycidyl methacrylate-modified elastomer was obtained in the same manner as in Experimental Example 3 at a cylinder temperature of 230 ° C.

G (D1) polymer: D polymer glycidyl methacrylate modified product (addition amount 1.82 parts by weight) G (D2) polymer: D polymer glycidyl methacrylate
Modified product (addition amount 1.42 parts by weight) G (D3) polymer: glycidyl methacrylate of D polymer
Modified product (addition amount 0.56 parts by weight) G (D4) polymer: glycidyl methacrylate of D polymer
Modified product (addition amount 0.03 parts by weight) (9) Preparation of maleic acid-modified block copolymer in solution (Synthesis Example 6) Maleic anhydride 25 per 100 parts by weight of elastomer D in toluene solvent 20 parts by weight of Perhexa 3M (manufactured by NOF CORPORATION) was added, and the mixture was heated at 110 ° C. for 7 hours
It was made to react for minutes. It was aggregated in a large amount of methanol and dried under vacuum. The following results were obtained by analyzing this modified block copolymer.

M (D5) polymer: Maleic anhydride-modified D polymer (addition amount: 5.62 parts by weight) (10) Preparation of glycidyl methacrylate-modified hydrogenated block copolymer in solution (Synthesis example) 7) The same experiment was performed except that glycidyl methacrylate was used in place of maleic anhydride in Synthesis Example 6. The following results were obtained by analyzing this modified block copolymer.

G (D5) Polymer: Glycidyl methacrylate modified product of D polymer (addition amount: 5.12 parts by weight) (11) Preparation of maleic acid modified hydrogenated block copolymer Part 3 (Synthesis Example 8) Elastomer -2.5 parts by weight of maleic anhydride to 100 parts by weight of each of I'and I "as components, and Sumilyzer-GM [trade name, manufactured by Sumitomo Chemical Co., Ltd.] as a stabilizer.
5 parts by weight, 0.25 parts by weight of Sumilizer-GS [manufactured by Sumitomo Chemical Co., Ltd., trade name], 0.4 parts by weight of Irganox 612 [manufactured by Ciba-Gaigi Co., Ltd.], dry blended, "Ene addition" was carried out at 240 ° C in the extruder.
The following results were obtained by analyzing this modified block copolymer.

M (I ') Polymer: Maleic anhydride modified product of I'polymer (addition amount 0.19 parts by weight) M (I ") Polymer: Maleic anhydride modified product of I" polymer (addition amount 0.12) (12 parts) Preparation of Elastomer-Grafted Polyamide (Synthesis Example 9) M (D1) Polymer 100 as Modified Hydrogenated Block Copolymer
100 parts by weight of nylon 6 is dry blended to 260 parts by weight in a 30 mm twin screw extruder at a residence time of about 9
The elastomer-grafted polyamide was prepared by melt mixing for 0 seconds and pelletizing. As a result of solvent composition fractionation according to the reference example, no elastomer having 92% by weight of elastomer-grafted polyamide and 8% by weight of polyamide and not grafted was found.

[0060]

Examples 1 to 5 Nylon 6, M (D1) polymer as a modified block copolymer and unmodified thermoplastic elastomer
As a result, the D polymer was dry-blended at the compounding ratio shown in Table 2, melt-mixed in a 30 mm twin-screw extruder at 260 ° C. for a residence time of about 50 seconds, and further pelletized to obtain a composition. The above composition was injection molded to obtain an Izod test piece. The notched Izod impact test was performed at 23 ° C. At the same time, the composition was divided into solvent-free composition, free-elastomer, elastomer-grafted polyamide, and free-polyamide for quantification. Further, the particle size of the elastomer particles was measured by SEM. Table 2 shows the results
Shown in

[0061]

[Comparative Examples 1 to 3] Nylon 6, modified block copolymer,
And unmodified thermoplastic elastomer were dry blended at the compounding ratios shown in Table 2, and otherwise the same as in Example 1. Table 2 shows the results.

[0062]

Examples 6 to 13 Nylon 6, a modified block copolymer, and an unmodified thermoplastic elastomer were each 80 /
Dry blending was performed under the conditions shown in Table 3 at a compounding ratio of 7.5 / 12.5, and otherwise the same as in Example 1. The results are shown in Table 3.

[0063]

[Comparative Example 4] M (D
Example 6 was repeated except that M (D5) was used instead of 1). The results are shown in Table 3.

[0064]

Examples 14 to 16 and Comparative Examples 5 to 8 Elastomer-grafted polyamide previously prepared in Experimental Example 9 (92% by weight of elastomer-grafted polyamide, 8% by weight of polyamide, 0% by weight of ungrafted elastomer). And nylon 6, and F polymer as an unmodified thermoplastic elastomer were dry-blended in the compounding ratio shown in Table 4, and otherwise the same as in Example 1. The results are shown in Table 4.

[0065]

Example 17 Nylon 6, M (D1) polymer as a modified block copolymer and D polymer as an unmodified thermoplastic elastomer were dry blended at a mixing ratio of 100: 12.5: 7.5, respectively. , 30 mm twin-screw extruder, melt-mixed at 260 ° C. for a residence time of about 60 seconds and pelletized to obtain a composition. Screw for kneading
The rotation speed was 50 rpm.

Evaluation of physical properties and the like were carried out in the same manner as the others. The results are shown in Table 5.

[0067]

Examples 18 to 19 Screw of 30 mm twin-screw extruder
Example 1 The number of rotations was set to 150 and 250 rpm, respectively.
The same procedure as 6 was performed. The results are shown in Table 5.

[0068]

[Comparative Examples 5 to 6] Nylon 6 and M (D1) as a modified block copolymer were dry blended at a compounding ratio of 100: 20 and the screw rotation speeds were 150 and 250 rpm, respectively.
Example 17 was repeated except that The results are shown in Table 5.
Shown in

[0069]

Examples 20 to 21 The same procedure as in Example 3 was repeated except that M (D2) and M (D3) were used instead of M (D1) as the modified block copolymer. The results are shown in Table 6.

[0070]

[Comparative Examples 7 to 8] The same procedure as in Example 3 was repeated except that M (D4) and M (D5) were used instead of M (D1) as the modified block copolymer. The results are shown in Table 6.

[0071]

[Embodiment 22] Instead of M (D1) in Embodiment 3, M (C) is
The same procedure was performed except that C was used instead of D. The results are shown in Table 7.

[0072]

[Examples 23 to 25] The same procedure as in Example 22 was repeated except that M (E), M (F) and M (KG) were used instead of M (C). The results are shown in Table 7.

[0073]

[Examples 26 to 28] The same procedure as in Example 1 was repeated except that G (D1), G (D2) and G (D3) were used instead of M (D1). Table 8 shows the results.

[0074]

[Comparative Examples 9 to 10] The same operation as in Example 26 was carried out except that G (D4) and G (D5) were used instead of G (D1). Table 8 shows the results.

[0075]

Example 29 Nylon 6, M (I ') as a modified block copolymer and an unmodified thermoplastic elastomer, respectively
B polymer as 100: 12.5: 7.5, respectively.
Was dry-blended at a compounding ratio of, and melt-mixed in a 30 mm twin-screw extruder at 240 ° C. for a residence time of about 50 seconds to be pelletized to obtain a composition.

Table 9 shows the results of the similar physical property evaluation.

[0077]

COMPARATIVE EXAMPLE 11 In Example 29, M (I ') was replaced with M
The same procedure was performed except that (I ″) was used.The results are shown in Table 9.

[0078]

Example 30 Nylon 12 was used instead of nylon 6 in Example 2, and the extrusion temperature was 220 ° C. and the residence time was about 120.
The procedure was the same except that the second was set. The results are shown in Table 10.

[0079]

[Example 31] Nylon 66 was used in place of nylon 12 in Example 2, and the extrusion temperature was 280 ° C and the residence time was 100.
The same operation was performed except that the second was set. The results are shown in Table 10.

[0080]

[Table 1]

[0081]

[Table 2]

[0082]

[Table 3]

[0083]

[Table 4]

[0084]

[Table 5]

[0085]

[Table 6]

[0086]

[Table 7]

[0087]

[Table 8]

[0088]

[Table 9]

[0089]

[Table 10]

[0090]

The polyamide resin composition of the present invention is excellent in processability and can be molded by various conventional molding methods such as extrusion molding, injection molding, calendar molding, film, sheet and molding. It is a useful substance that has excellent mechanical properties in various fields such as products and rubber applications, especially excellent balance of bending elasticity and impact resistance, and has a wide range of applications.

Claims (1)

(57) [Claims] 1. (a) Polyamide resin 10 to 85 weight
%, (B) at least two vinyl aromatic compound blocks
KU A and at least one unsaturation degree not exceeding 20%
It consists of a polymer block B of reffin compound and has a vinyl aroma.
Block containing 10 to 90% by weight of group compound
Graft copolymer in which polyamide is grafted to polymer
(Elastomer-grafted polyamide) 10-55 weight
%, (C) thermoplastic elastomer-5-40% by weight, and
(D) At least two vinyl aromatic compound blocks A
And at least one olef with a degree of unsaturation not exceeding 20%
Made of vinyl compound polymer block B
Block copolymer having a compound content of 10 to 90% by weight
The unsaturated carboxylic acid or its derivative
0.05 to 3 parts by weight were bonded per 100 parts by weight of the copolymer.
Comprising 0 to 30% by weight of modified block copolymer component
A composition (where (a) + (b) + (c) + (d)
= 100%), (b) elastomer-grafted polyamid
The polyamide component in the resin is 10 to 70% by weight,
Elastomer in elastomer-grafted polyamide and (c)
And (c) in the total of (d) elastomer
And (d) proportion of elastomer (non-grafted elastomer
(M) is 35 to 85% by weight, and is a polyamide resin.
The number average particle size (d) of the elastomer component in the fat composition._n)
Is 0.1 ≦ d_n≤ (1.39353 x 10^-Four) × E³−
(3.56763 x 10 ^-3) × E²+ (3.89005
× 10^-2) × E + 0.05 μm (where E is the total composition)
(Representing the weight percent of the net elastomer component of)
Polyamide resin composition with excellent impact resistance characterized by
Stuff.