JP2006307208A - Maleated thermoplastic resin and process for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an efficient synthesis method which inhibits the gelling and discoloration of a maleated thermoplastic resin and does not leave impurities behind and a maleated thermoplastic resin useful in blending with a high polarity resin having a functional group such as an ethylene-vinyl alcohol resin. <P>SOLUTION: The maleated thermoplastic resin is obtained by maleating a hydrocarbon polymer having double bonds in the main chain and a number average molecular weight of 15,000-100,000 with at least part of the maleic acid group being esterified, particularly at a ratio of maleation of 0.1-3 wt.%. The method for producing the maleated themoplastic resin comprises reacting a hydrocarbon resin having double bonds in the main chain with maleic anhydride in the presence of 300-3,000 mol% alcohol based on the maleic anhydride. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a maleated thermoplastic resin and a method for producing the same. More specifically, it is a maleated thermoplastic resin in which a resin having a double bond in the main chain having a number average molecular weight of 15,000 to 100,000 is maleated to 0.1 to 3% by weight, wherein at least a part of the maleic acid group is present. Maleation of an esterified maleated thermoplastic resin, a resin having a double bond in the main chain, and maleic anhydride in the presence of 300 to 3000 mol% alcohol based on maleic anhydride The present invention relates to a method for producing a thermoplastic resin.

  The maleated thermoplastic resin obtained by modifying a hydrocarbon polymer having a double bond with maleic anhydride, etc. is a raw material for water-based paints and metal corrosion-preventing paints because of its toughness and water resistance. It is used as a raw material. In addition to giving elasticity to the resin, the hydrocarbon-based polymer having a double bond is superior in compatibility and adhesion to polar resins compared to the hydrocarbon-based polymer before maleating. Therefore, it is used in various fields as a resin modifier.

  Various types of maleated thermoplastic resins and methods for producing the same have been known. For example, Patent Document 1 discloses a method for producing a maleated synthetic cis-1,4-polyisoprene rubber, Patent Document 2 discloses a method for producing a butadiene low-polymerized adduct, and Patent Document 3 discloses a light anhydrous maleic anhydride. An acid-added butadiene low polymer and a method for producing the same are disclosed in Patent Document 4, in which 5 to 30% by weight of maleic acid is added to a conjugated diolefin polymer or copolymer, and a partial ester is present in the presence of a monohydric alcohol. It has been disclosed that the resin composition thus obtained is firmly bonded to a metal and excellent in preventing corrosion of the metal. However, it is described that such an excellent effect is not exhibited when the addition rate of maleic acid is less than 5% by weight.

  On the other hand, vinyl alcohol resins such as ethylene-vinyl alcohol copolymer (hereinafter sometimes abbreviated as EVOH) are widely used in food containers and the like due to their excellent gas barrier properties and transparency. Yes. However, since EVOH is relatively inflexible, it is a common practice to improve mechanical properties by blending other resins.

JP 49-121892 A JP 56-149403 A JP-A-53-134895 JP-A-54-008132

  However, it has been difficult to use these conventional maleated thermoplastic resins for improving the mechanical properties of EVOH. First, in general, these maleated thermoplastic resins tend to increase in viscosity and gel during storage unless a stabilizer is added, and this tendency is particularly high except for hydrogen present in the main chain carbon. In the case of a resin having a small amount of substituents or a large maleinization rate, the tendency becomes remarkable. However, for example, the above EVOH is often used in food applications, but if a stabilizer is added to prevent thickening during storage, the stabilizer may bleed out and affect food. there were. Therefore, in order to use for such a use, it is desired that it is stable even if an additive such as a stabilizer is not present.

  When the maleated thermoplastic resin produced by the method disclosed in Patent Document 1 is melt-mixed with EVOH by an ordinary method, a gelled product is generated and appearance defects tend to occur. This is presumed to be because the molecular weight of the resin or the maleinization rate is relatively high, and a partial cross-linking occurs during the production. On the other hand, if the maleation rate is lowered so that the above problems do not occur, sufficient compatibility with EVOH cannot be obtained, and the brittleness improvement effect is difficult to obtain.

  Since the maleated thermoplastic resins disclosed in Patent Documents 2 and 3 have a number average molecular weight as small as 2000 or less, the effect of improving the mechanical properties of EVOH is not sufficient when added in a small amount. There was a tendency to reduce the gas barrier property, which is a characteristic of EVOH, and to cause gelation during molding.

  Furthermore, since the maleated thermoplastic resin is easily gelled during its production, it is difficult to produce the maleated thermoplastic resin. In particular, the main chain carbon does not have a methyl group, and double bonds existing in addition to the main chain are less than 10 mol% of the total double bonds, such as 1,4-polybutadiene, and the main chain carbon is not much substituted. In the case of maleating a resin that does not have, the tendency is remarkably difficult to manufacture.

  For example, Patent Document 1 discloses a method of preventing gelation by adding an appropriate amount of water, and Patent Documents 3 and 4 disclose a method of adding water or alcohol. However, in these methods, if too much water or alcohol is added, the solubility of the resin is lowered and the maleation reaction itself is hindered, so there is a limit to the amount of water or alcohol that can be added, resulting in gelation. Although not so far, there was a tendency that a certain amount of a high molecular weight product was produced during the production, and the storage stability of the produced resin was not good.

  In Patent Document 2, a phenolic compound is considerably added to prevent gelation. However, in this method, the additive remains in the resin. Bleed out can be a problem.

  The object of the present invention is that when added to a vinyl alcohol polymer such as EVOH, it does not cause deterioration in properties such as poor appearance and gas barrier properties, has an effect of improving mechanical properties, particularly brittleness, and has storage stability. The present invention is to provide a maleated thermoplastic resin that is good and has no problems such as bleeding out.

  Another object of the present invention is to efficiently produce such maleated thermoplastic resin without causing gelation and coloring and leaving no impurities.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have made a maleinization without problems such as gelation by maleating a resin having a double bond in the main chain in the presence of a specific amount of alcohol. It has been found that a thermoplastic resin can be produced. Furthermore, the maleated thermoplastic resin obtained by esterifying the maleic acid group thus obtained has good storage stability and has an effect of improving mechanical properties when added to EVOH. The invention has been completed.

  That is, the present invention is a maleated thermoplastic resin obtained by maleating a resin having a double bond in the main chain having a number average molecular weight of 15,000 to 100,000, wherein at least a part of the maleic acid group is esterified. It is a maleated thermoplastic resin.

  Another aspect of the present invention is characterized in that a resin having a double bond in the main chain is reacted with maleic anhydride in the presence of 300 to 3000 mol% alcohol with respect to maleic anhydride. This is a method for producing a maleated thermoplastic resin.

  According to the present invention, the storage stability is good, and the brittleness of vinyl alcohol resins such as EVOH and other resins having polar reactive groups can be molded without problems such as gelation during molding, poor appearance of the product, and bleed out from the product. A maleated thermoplastic resin that can be improved by slowly radical-crosslinking the subsequent double bond is provided.

  Furthermore, the present invention eliminates problems such as gelation in the production of maleated thermoplastic resins without adding additives that cause problems when commercialized, and has the above characteristics. A method for efficiently producing a thermoplastic resin is provided.

  A first invention of the present invention is a maleated thermoplastic resin obtained by maleating a resin having a double bond in the main chain having a number average molecular weight of 15,000 to 100,000, wherein at least a part of the maleic acid group is esterified It is a maleated thermoplastic resin.

  In the maleated thermoplastic resin of the present invention, a resin having a number average molecular weight of 15,000 to 100,000 and having a carbon-carbon double bond in the main chain (hereinafter sometimes referred to as resin (A)) is maleated. Become.

  When the molecular weight of the resin (A) is 15000 or less, the effect of improving mechanical properties by mixing with EVOH or the like is small, and the maleated thermoplastic resin increases the risk of bleeding out from the product. On the other hand, when the molecular weight of the resin (A) is 100,000 or more, the compatibility when mixed with EVOH tends to deteriorate. If the maleation rate is increased to improve the compatibility, gelation due to crosslinking or the like Is more likely to occur. In addition, when the molecular weight of the resin (A) is larger than 100,000, gelation and high molecular weight are easily generated during the maleating reaction, so that the manufacturing difficulty increases. In view of the effect of improving brittleness, the molecular weight is preferably 20000 or more, and more preferably 30000 or more. On the other hand, the molecular weight is preferably 90000 or less, and more preferably 80000 or less from the viewpoint of making it difficult to cause poor appearance during molding.

  A hydrocarbon resin is used as the resin (A). The hydrocarbon-based resin here is a resin mainly composed of carbon and hydrogen, but may have a functional group such as an ether bond, an ester group, and an amide bond as long as the effects of the present invention are not impaired. Absent. Usually, the maleated thermoplastic resin has high stability and does not have a functional group as described above from the viewpoint of avoiding reaction or interaction with a base resin such as EVOH or an additive in the base resin. A hydrocarbon resin is used.

  In addition, when the maleated thermoplastic resin is used as a composition with EVOH for the purpose of improving the mechanical properties of EVOH, the resin (A) is not branched from the viewpoint that it is difficult to lower the original gas barrier property of EVOH. Are preferred, and those having no substituent in the main chain are preferred.

  Resin (A) has double bonds in the main chain for the purpose of improving brittleness of vinyl alcohol resins such as EVOH and other resins having polar reactive groups by gently radical crosslinking of the double bonds after molding. . The carbon-carbon double bond of the resin (A) may be present in a portion other than the main chain, that is, in a portion branched from the main chain. However, when the maleated thermoplastic resin is mixed with EVOH, the gas barrier properties of EVOH, etc. From the viewpoint of reducing the possibility of gelation without impairing the properties, it is preferably mainly present in the main chain. Specifically, in the resin having a double bond in the main chain, among the double bonds contained, the double bond existing other than the main chain is a full double bond of the resin having a double bond in the main chain. It is preferable that it is 10 mol% or less of the quantity.

  Further, from the viewpoint of facilitating maleation, it is necessary that at least one hydrogen atom is bonded to the allylic carbon of the double bond contained in the main chain of the resin (A).

  From such a viewpoint, the resin (A) preferably contains at least one of the structural units represented by the following structural formula (I) and structural formula (II), and is substantially composed of a double bond contained in the main chain. It is more preferable that all of these are any of the structures represented by the following structural formulas (I) and (II).

  Examples of the resin (A) that can be used in the present invention include diene polymers such as polyisoprene and polybutadiene; diene copolymers such as styrene-butadiene copolymer, styrene-isoprene copolymer, and acrylonitrile-butadiene copolymer. Examples thereof include metathesis polymers such as polyoctenylene and ring-opening metathesis polymers of cyclooctadiene.

  Among the above-mentioned resins, preferable examples of the resin (A) constituting the maleated thermoplastic resin of the present invention include 1,4-polybutadiene and a ring-opening metathesis polymer of a cyclic hydrocarbon containing a double bond. Among these, a ring-opening polymer of 1,4-cis polybutadiene, polyoctenylene, and cyclooctadiene is particularly preferably used because it is easy to produce and obtain.

  Examples of the commercially available 1,4-cis polybutadiene used in the present invention include LIR-300 manufactured by Kuraray Co., Ltd. Examples of the 1,4-cis polybutadiene copolymer include LIR-390 manufactured by Kuraray Co., Ltd.

  In the maleated thermoplastic resin of the present invention, the resin (A) is maleated, and at least a part of the maleic acid group introduced by maleating is esterified.

  Here, maleation means addition of an acid anhydride having the same reactivity as maleic anhydride and maleic anhydride (hereinafter sometimes referred to as acid anhydride (B)) or a derivative thereof. Thus, maleated means that the structural unit of the acid anhydride (B) or a derivative thereof is bonded to the allylic position of the resin having a double bond in the main chain.

  Examples of the acid anhydride (B) include maleic anhydride, citraconic anhydride, 2,3-dimethylmaleic anhydride, bromomaleic anhydride, chloromaleic anhydride, dichloromaleic anhydride, crotonic anhydride, 3,4, Examples include 5,6-tetrahydrophthalic anhydride, itaconic anhydride, glutaconic anhydride and the like. Of these, maleic anhydride is the most representative.

  The maleation rate of the maleated thermoplastic resin of the present invention, that is, the amount of the acid anhydride (B) unit relative to the maleated thermoplastic resin weight is not particularly limited, but gelation, etc. when mixed with EVOH and melt molded From the viewpoint of not causing this problem, the maleation rate is 3% by weight or less, preferably 2.5% by weight or less. On the other hand, in order to improve the compatibility of the resin, it is necessary that the maleation rate is a certain level or more. The maleation rate is preferably 0.1% by weight or more, and more preferably 0.5% by weight or more. More preferably.

  The amount of maleic acid unit contained in the maleated thermoplastic resin of the present invention is quantified by acid value measurement. The maleation rate referred to here is the amount of maleic acid units converted to the weight of the acid anhydride and divided by the total weight of the maleated thermoplastic resin.

  In the present invention, at least a part of the maleic acid group is esterified. Since at least a part of the maleic acid group is esterified, the storage stability of the maleated thermoplastic resin is remarkably improved. Even if the maleic acid group is esterified, the maleated thermoplastic resin of the present invention has good affinity with EVOH and the like.

  The method for esterifying the maleic acid group is not particularly limited. The resin (A) may be reacted with an acid anhydride (B) and then reacted with an alcohol. It is preferable to carry out the maleation reaction and the esterification reaction simultaneously by a similar method.

  When the maleic acid group is esterified in the presence of an alcohol, the acid anhydride group is opened, and one alcohol is added to one maleic acid group to form one ester group and one carboxylic acid group. In some cases, a so-called half-ester structure having a diester structure is formed, and two alcohols are added to form a diester structure having two ester groups. In the case of esterification in the present invention, both carboxylic acid groups derived from an acid anhydride may be esterified, but usually the above-mentioned synthetic reasons and the affinity with the resin are maintained. This half ester structure is preferable from the viewpoint of making it difficult for problems such as gelation to occur.

  In the present invention, it is sufficient that at least a part of the maleic acid group is esterified, and the esterification rate corresponding to the ratio of the ester group to the maleic acid group can take various values. In order not to cause problems such as gelation when blended with a resin or other resin having a polar reactive group, the esterification rate is preferably 80 mol% or more. The ratio of these structures varies depending on the production method, but if the esterification rate exceeds 180 mol%, the compatibility is deteriorated when blended with EVOH or the like, which is not preferable. A more preferable esterification rate is 150 mol%. Furthermore, it is preferable that substantially all maleic acid groups have a half ester structure. Here, “substantially all half-esterified” means that the esterification rate is 95 mol% to 105 mol%.

  Here, the type of ester of the esterified maleic acid group is not particularly limited, but the alcohol unit forming the ester moiety is preferably one that does not have reactivity with an alcoholic hydroxyl group. Examples of the alcohol unit include monovalent alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, amyl alcohol, isoamyl alcohol, 1-hexanol, 1-octanol, 2-ethylhexyl alcohol, and decyl alcohol. Chain aliphatic alcohols; cycloaliphatic alcohols such as cyclohexanol and cyclohexanemethanol; aromatic alcohols such as benzyl alcohol, 2-phenylethanol and 2-phenylpropanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, diethylene glycol monomethyl ether, triethylene Glycol ethers such as glycol monomethyl ether and polyethylene glycol monomethyl ether; ethylene glycol monoacetate Glycol esters such as diethylene glycol monoacetate, triethylene glycol monoacetate, polyethylene glycol monoacetate, etc .; polyglycols such as ethylene glycol and propylene glycol, which are divalent alcohols, or polymers obtained by polymerizing glycols Glycols; and the like. Among these, monohydric alcohols having 5 or less carbon atoms, that is, methanol, ethanol, 1-propanol, 2-propanol, n-butanol, isobutyl alcohol, amyl alcohol, in view of the affinity between maleated thermoplastic resin and EVOH. Is preferred. Esters may be composed of only one of these alcohol units, or may be composed of two or more.

  Hereinafter, a method for producing a maleated thermoplastic resin, which is another invention of the present invention, will be described.

  In the method for producing a maleated thermoplastic resin of the present invention, a resin having a double bond in the main chain and maleic anhydride are reacted in the presence of 300 to 3000 mol% alcohol with respect to maleic anhydride. Features.

  The maleic anhydride here includes not only maleic anhydride itself but also the above acid anhydride (B).

  The amount of these acid anhydrides to be used may be determined according to the target maleation rate, but in order to satisfy the requirements for the maleated thermoplastic resin, the amount of acid anhydride is preferably 0. 0 relative to the resin (A). 1-3% by weight is used. The reaction may be introduced in the form of a lump, granule, or powder, but can be introduced by dissolving or dispersing in a solvent to be used, coexisting water or alcohol.

  The resin (A) already described can be used as the resin having a double bond in the main chain.

  The alcohol used in the present invention is not particularly limited as long as it does not have a functional group that reacts with the alcohol itself or a moiety to which maleic anhydride can be added, that is, a double bond having an allylic hydrogen atom in the molecule. Usually, any carboxylic acid that can be esterified can be used. As such an alcohol, one or two or more of the alcohols listed as the alcohol unit constituting the maleate can be used, but from the viewpoint of preventing gelation of the produced maleated thermoplastic resin. Is preferably a monohydric alcohol. Further, from the viewpoint of ease of operation such as removal of alcohol after the reaction and affinity of the produced maleated thermoplastic resin with vinyl alcohol resin, preferred alcohols include methanol, ethanol, 1-propanol, 2- Saturated hydrocarbon alcohols such as propanol, 2-butanol, 1-butanol, amyl alcohol, and cyclohexanol can be used.

  Among these, the alcohol is preferably a saturated aliphatic alcohol having a boiling point of 100 ° C. or less from the viewpoint that it can be easily removed from the resin composition after the reaction. Examples of such alcohol include methanol, ethanol, 1-propanol, 2-propanol, and 2-butanol.

  The amount of alcohol used in the method of the present invention is 300 mol% or more and 3000 mol% or less with respect to maleic anhydride. If the amount of alcohol used is smaller than this, gelation is likely to occur particularly when a product having a high maleation rate is to be produced. In this respect, the amount of alcohol used is preferably 400 mol% or more. On the other hand, if the amount of alcohol used is too large, the solubility of the resin will deteriorate and the reaction efficiency will decrease. From such a viewpoint, the amount of alcohol used is preferably 2000 mol% or less, more preferably 1000 mol% or less.

  Usually, when the reaction is carried out in the presence of such a large amount of alcohol, as described in Patent Document 3 and the like, esterification of maleic anhydride proceeds competitively and the reactivity decreases. It tends to be difficult to increase the conversion rate. In the present invention, when the resin and maleic anhydride are reacted, the reactivity can be greatly increased even in the presence of an alcohol by coexisting an organic solvent other than the alcohol.

  The organic solvent other than the alcohol used in the present invention may be any one that does not inhibit the maleation reaction, and is an aliphatic hydrocarbon solvent such as n-hexane, cyclohexane, or methylcyclohexane, or an aromatic such as benzene, toluene, or xylene. Group hydrocarbon solvents, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, acetone, isophorone and cyclohexanone, ether solvents such as tetrahydrofuran, dioxane, dimethyl ether and anisole, acetal solvents such as methylal and diethyl acetal, methyl acetate and acetic acid Esters such as ethyl, acetic acid-n-butyl, acetic acid-n-amyl, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl Active against radical reactions of polyhydric alcohol derivatives such as ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, halogenated hydrocarbon solvents such as carbon tetrachloride, 1,1,1-trichloroethane and dichlorobenzene One type or two or more types of solvents that do not have a solvent are used. Considering the influence of the remaining organic solvent on the environment, ease of handling, solubility, etc., it is preferable to use hydrocarbon solvents such as toluene, xylene, cyclohexane, methylcyclohexane, and reaction to the desired maleated polybutadiene polymer. In view of the properties and solubility, cycloaliphatic compounds, particularly cyclohexane, are preferred.

  Although the usage-amount of organic solvents other than the said alcohol is not specifically limited, What is necessary is just the quantity which can fully exhibit the fluidity | liquidity of the melted polybutadiene. Therefore, depending on the structure and molecular weight of the resin having a double bond in the main chain, generally, the resin having a double bond in the main chain is 0.1 to 50% by weight based on the entire reaction solution, Preferably, a solvent is used so as to be 3 to 30% by weight.

  The reaction temperature in the present invention is usually 100 ° C. or higher. In particular, the temperature is preferably 120 ° C. or higher because the fluidity of the polymer is maintained and the maleation proceeds homogeneously. On the other hand, if the reaction is carried out at a too high temperature, side reactions tend to increase, so the temperature is usually 300 ° C. or lower, preferably 250 ° C. or lower.

  At the above reaction temperature, depending on the solvent used, the vapor pressure of the solvent exceeds atmospheric pressure. In this case, the reaction is carried out under pressure. Regardless of the vapor pressure of the solvent, the maleation reaction rate can be improved by pressurizing the vapor pressure higher than that of the solvent using an inert gas such as nitrogen. Therefore, although the pressure during the reaction depends on the solvent used and the dissolution concentration, it is preferably carried out in the range of 0.1 to 4 MPa, and more preferably in the range of 0.1 to 1.5 MPa.

  In the present invention, an organic peroxide as a catalyst is used as necessary. As the organic peroxide of the catalyst used in the present invention, diacyl peroxides such as benzoyl peroxide, 2,4-dichlorobenzoic peroxide, octanoyl peroxide, lauroyl peroxide, di-t-butyl peroxide, Dialkyl peroxides such as 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, dicumyl peroxide, α, α'-bis (t-butylperoxy-m-isopropyl) benzene Peroxyesters such as t-butyl perbenzoate, t-butyl peracetate, di-t-butyl perphthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane; methyl ethyl ketone peroxide; Ketone peroxides such as cyclohexanone peroxide; di- -Hydroperoxides such as butyl hydroperoxide, cumene hydroperoxide, α-phenylethyl hydroperoxide, cyclohexenyl hydroperoxide; 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis One or a mixture of two or more peroxyketals such as (t-butylperoxy) -3,3,5-trimethylcyclohexane can be used. The amount used is 0.0001 to 1% by weight, preferably 0.001 to 0.5% by weight, based on the resin (A).

Further, after completion of the reaction time or reaction, the reaction system 2,6-di -tert- butyl-4-methylphenol, p- methoxy-quinone, hydroquinone, 4,4 ^'- thiobis (6-tert-butyl-3-methylphenol phenol), N, N ^'- may be added diphenyl -p- phenylenediamine known polymerization inhibitor.

  The maleated thermoplastic resin of the present invention is used as a resin composition with EVOH as an example. If the ethylene ratio of EVOH used in the present invention is less than 10 mol%, the compatibility with the maleated thermoplastic resin is impaired, so the ethylene ratio is preferably in the range of 10 to 95 mol%, and the gas barrier properties of EVOH are not impaired. In consideration of the ethylene ratio, the range of 10 to 60 mol% is more preferable.

  Further, EVOH is added to the resin composition of the maleated thermoplastic resin of the present invention and EVOH as long as it does not contain a group that reacts with a compound such as a heat stabilizer or lubricant or an acid anhydride in excess of the vinyl alcohol ratio of EVOH. Also good.

The amount of maleated thermoplastic resin added to EVOH is less than 0.1% by weight of maleated thermoplastic resin, and there is no EVOH modification effect. If it exceeds 40% by weight, the transparency and rigidity of the resin composition are impaired. The range of 0.1 to 40% by weight is preferable, and 0.1 to 30% by weight is more preferable in consideration of the gas barrier property of EVOH and the effect of the maleated thermoplastic resin.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the scope of the present invention is not limited by these examples.

  In the following Examples, the maleic acid group of maleated thermoplastic resin was quantified, the esterification rate was quantified, and the molecular weight distribution was quantified by the following method.

[Quantification of maleic acid group]
A 400 mg sample was dissolved in 80 mL of tetrahydrofuran (hereinafter sometimes abbreviated as THF), titrated with a 0.05 mol / L potassium hydroxide ethanol solution with correction, and the acid value and maleation rate were determined from the titration value. Was obtained by the following formula. However, the constant 56.1 in the following formula is the molecular weight of potassium hydroxide, and the constant 98.1 is the molecular weight of maleic anhydride. When the above-mentioned acid anhydride (B) other than maleic anhydride is used during maleation, the molecular weight of the corresponding acid anhydride is appropriately substituted into the following formula for calculation.
Acid value (mgKOH / g)
= ([Titration value (mL)]-[Blank value (mL)]) × 56.1 × 0.05 × [Correction value of ethanol solution of potassium hydroxide] ÷ [Mass (mg)]
Maleinization rate (wt%)
= [Acid value (mgKOH / g)] ÷ 56.1 × 98.1 ÷ 1000 × 100 ÷ 2

[Quantification of esterification rate]
A viscous liquid sample was directly applied to a quartz cell of a Fourier transform infrared absorption measuring apparatus FT-IR without dilution, and measured by a transmission method. Absorption rate peak (1710 cm ⁻¹ ) height derived from carboxylic acid group of IR obtained is x, height of peak (1740 cm ⁻¹ ) derived from ester group is y, peak derived from acid anhydride group When the height of (1780 cm < ^-1 >) was set to z, the esterification rate was computed according to the following formula | equation.
Esterification rate (mol%) = 100 × 2y / (x + y + z)

[Quantitative method of molecular weight distribution]
10 mg of a sample was dissolved in 10 mL of THF for liquid chromatography, the solution was passed through a 0.45 μm filter to prepare a measurement sample, and then measured with THF for liquid chromatography. The molecular weight was determined from a calibration curve prepared separately from values obtained by measuring polystyrene having a defined molecular weight by the same method.

[Measurement method of notched Izod impact strength at −40 ° C.]
Measurement was performed based on JIS standard K7110. The prepared test piece was stored at −40 ° C. for 7 days, and the impact strength was measured with an impact strength measuring instrument.

1,4-cis polybutadiene (manufactured by Kuraray Co., Ltd., LIR-300, number average molecular weight (hereinafter referred to as Mn) 50000, 1,4-bond content = 90 mol%) 30 g, maleic anhydride 0.3 g, cyclohexane 200 g Then, 3 g of ethanol was charged into a 500 mL autoclave and brought to a nitrogen atmosphere, 0.1 g of di-t-butyl hydroperoxide was added, and the mixture was reacted at 140 ° C. and 10 kgf / m ² for 3 hours with stirring. As a result of analyzing the reaction solution by gas chromatography (hereinafter referred to as GC), unreacted maleic anhydride was 0.1 wt% or less. Next, the solvent in the reaction solution was distilled off at 100 ° C. and vacuum-dried at room temperature for 8 hours to obtain 30.3 g of a colorless and transparent maleated cis-polybutadiene (sample 1). The acid value of Sample 1 was 11.4 (half acid value, KOH mg / g), and the maleation rate was 1.0% by weight.

  Moreover, when it measured by IR, the acid anhydride peak was not recognized, but all the maleic anhydrides were esterified, and it turned out that all the maleic groups of the sample 1 were half-esterified substantially. Furthermore, the result of having measured the molecular weight distribution of the sample 1 by GPC is shown in FIG. As shown in FIG. 1, no high molecular weight product was observed in Sample 1. In addition, Sample 1 was excellent in storage stability with no increase in viscosity even when stored at room temperature in air for 30 days.

Sample 1 was synthesized in the required amount, and 10 parts by weight of sample 1 and Kuraray Eval L101 (ethylene content 27 mol%, saponification degree 99.7 mol%, in hydrous phenol in a twin screw segment extruder with a screw diameter of 25 mmφ 90 parts by weight of an intrinsic viscosity of 1.1 dL / g at 30 ° C. was supplied, and extrusion pelletization was performed under the following conditions.
Temperature condition (° C.): C1 / C2 / C3 / C4 / C5 / die = 220/220/220/220/220/220
Discharge rate: 2kg / h
Screw rotation speed: 115rpm

The obtained pellets were injection molded to prepare test pieces, and the impact strength was measured with an impact strength measuring device based on the method of JIS standard K7110. This test piece had a notched Izod impact strength at −40 ° C. of 7 kJ / m ² .

  1,4-cis polybutadiene (manufactured by Kuraray Co., Ltd., LIR-300, number average molecular weight (hereinafter referred to as Mn) 50000, 1,4-bond content = 90 mol%) 30 g, maleic anhydride 0.3 g, xylene 200 g Then, 3 g of ethanol was charged into a 1 L separable flask and brought to a nitrogen atmosphere, and then 0.1 g of di-t-butyl hydroperoxide was added and reacted at 140 ° C. for 3 hours with stirring. As a result of analyzing the reaction solution by GC, unreacted maleic anhydride was 0.1% by weight or less. Next, the solvent in the reaction solution was distilled off at 100 ° C., followed by vacuum drying at room temperature for 8 hours to obtain 30.3 g of a colorless and transparent maleated cis-polybutadiene (Sample 2). The acid value of Sample 2 was 11.4 (half acid value, KOH mg / g), and the maleation rate was 1.0% by weight. Further, when measured by IR, no acid anhydride peak was observed, and all of maleic anhydride was esterified. The obtained maleated cis-polybutadiene did not increase in viscosity even when stored for 30 days, and was excellent in storage stability.

It was 6.8 kJ / m < ² > when the Izod impact strength with a notch in -40 degreeC was measured similarly to Example 1 about the said sample 2. FIG.

Polyoctenylene (Degussa VESTENAMER 8012 Mn = 90,000, cis / trans = 20/80) 30 g, maleic anhydride 0.3 g, cyclohexane 300 g, and ethanol 3 g were charged into a 1 L autoclave and brought to a nitrogen atmosphere, and then di-t-butyl Hydroperoxide 0.1g was added and it was made to react at 140 degreeC and 10 kgf / m < ² > for 3 hours, stirring. As a result of analyzing the reaction solution by GC, unreacted maleic anhydride was 0.1% by weight or less. Next, the solvent in the reaction solution was distilled off at 100 ° C., followed by vacuum drying at room temperature for 8 hours to obtain 30.3 g of a colorless and transparent maleated polyoctenylene (Sample 3). The acid value of Sample 3 was 11.4 (half acid value, KOH mg / g), and the maleation rate was 1.0% by weight. Further, when measured by IR, no acid anhydride peak was observed, and all of maleic anhydride was esterified. The maleated polyoctenylene obtained did not increase in viscosity even when stored for 30 days, and was excellent in storage stability.

30 g of a resin having a molecular weight of 45000 obtained by ring-opening metathesis polymerization of cyclooctadiene with an organometallic catalyst, 0.3 g of maleic anhydride, 200 g of cyclohexane, and 3 g of ethanol were charged in a 1 L autoclave and brought into a nitrogen atmosphere, and then di-tert-butyl Hydroperoxide 0.1g was added and it was made to react at 140 degreeC and 10 kgf / m < ² > for 3 hours, stirring. As a result of analyzing the reaction solution by gas chromatography (hereinafter referred to as GC), unreacted maleic anhydride was 0.1 wt% or less. Next, the solvent in the reaction solution was distilled off at 100 ° C. and vacuum-dried at room temperature for 8 hours to obtain 30.3 g of colorless and transparent maleated poly (cyclooctadiene) (Sample 4). The acid value of Sample 4 was 11.4 (KOHmg / g), and the maleation rate was 1.0% by weight. Further, when measured by IR, no acid anhydride peak was observed, and all of maleic anhydride was esterified. The maleated poly (cyclooctadiene) obtained did not increase in viscosity even after storage for 30 days, and was excellent in storage stability.

[Comparative Example 1]
1,4-cis polybutadiene (manufactured by Kuraray Co., Ltd., LIR-300, number average molecular weight (hereinafter referred to as Mn) 50000, 1,4-bond content = 90 mol%) 300 g, maleic anhydride 3 g in 1 L separable flask Was added to a nitrogen atmosphere, and 0.1 g of di-t-butyl hydroperoxide was added and reacted at 140 ° C. for 6 hours with stirring to obtain a maleated cis-polybutadiene quantitatively (Sample 5). . Sample 5 was dissolved in xylene and analyzed by GC. As a result, unreacted maleic anhydride was 0.1% by weight or less. The acid value of Sample 5 was 11.4 (half acid value, KOH mg / g), and the maleation rate was 1.0% by weight. Moreover, when measured by IR, only the acid anhydride peak was observed, and esterification and hydrolysis were not carried out. However, Sample 5 was thickened and yellowed. Moreover, the result of having measured the molecular weight distribution of the obtained maleated cis polybutadiene by GPC is shown in FIG. As shown in FIG. 1, in Sample 5, the production of a high molecular weight was observed. When Sample 5 was stored at room temperature under nitrogen for 30 days, thickening was further observed and the storage stability was not good.

[Comparative Example 2]
A 500 mL autoclave containing 30 g of 1,4-cis polybutadiene with Mn = 390000 (manufactured by ZEON Corporation, Nipol IR2200, 1,4-bond content = 90 mol% or more), 0.3 g of maleic anhydride, 300 g of cyclohexane, and 3 g of ethanol. After charging and making a nitrogen atmosphere, 0.1 g of di-t-butyl hydroperoxide was added and reacted at 140 ° C. and 10 kgf / m ² for 3 hours with stirring. As a result of analyzing the reaction solution by GC, unreacted maleic anhydride was 0.1% by weight or less. Next, the solvent in the reaction solution was distilled off at 100 ° C. and vacuum-dried at room temperature for 8 hours to obtain 30.1 g of a colorless and transparent maleated cis-polybutadiene (sample 6).

  The acid value of Sample 6 was 11.4 (half acid value, KOH mg / g), and the maleation rate was 1.0% by weight. Further, the maleic acid group of Sample 6 was quantitatively esterified. This maleated cis-polybutadiene was not cured even after storage for 30 days and was excellent in storage stability.

Sample 6 was measured for notched Izod impact strength at −40 ° C. in the same manner as in Example 1. However, a large amount of irregularity in the molten state was generated in the obtained test piece.

[Comparative Example 3]
In place of 1,4-cis polybutadiene having a Mn of 390000 in Comparative Example 2 above, 1,4-cis polybutadiene having a molecular weight of 1600 (Poly Oil 110 1,4-bond content = 99 mol% manufactured by Nippon Zeon Co., Ltd.) was used. The maleation reaction was carried out in the same manner as in Comparative Example 2 except that 30.1 g of a colorless and transparent maleated cis-polybutadiene (sample 7) was obtained.

  The acid value of Sample 7 was 11.4 (half acid value, KOH mg / g), and the maleation rate was 1.0% by weight. Further, the maleic acid group of Sample 7 was quantitatively esterified. This maleated cis-polybutadiene was not cured even after storage for 30 days and was excellent in storage stability.

Sample 7 was measured for notched Izod impact strength at −40 ° C. in the same manner as in Example 1. However, the obtained test piece was found to have irregularities due to non-uniformity of the sample, and the value was Compared with EVOH in which sample 7 was not mixed at 2.4 kJ / m ² , it was not so improved.

[Comparative Example 4]
The maleation reaction was carried out by changing the amount of ethanol in Example 1 from 3 g to 0.1 g to obtain 30.3 g of a pale yellow transparent maleated cis polybutadiene (sample 8).

  The acid value of Sample 8 was 11.4 (half acid value, KOH mg / g), and the maleation rate was 1.0% by weight. Moreover, when measured by IR, the esterification rate was 21 mol%. This maleated cis-polybutadiene was yellowed and cured after storage for 30 days.

[Comparative Example 5]
The amount of maleic anhydride in Example 1 was changed from 0.3 g to 1.8 g, and the amount of ethanol, cyclohexane, and di-t-butyl hydroperoxide was changed to 6 times with the change in the amount of maleic anhydride. The maleation reaction was carried out to obtain 31.6 g of a colorless and transparent maleated cis-polybutadiene (sample 9).

  The acid value of Sample 9 was 67.7 (half acid value, KOH mg / g), and the maleation rate was 5.9% by weight. Further, the maleic acid group of Sample 9 was quantitatively esterified. This maleated cis-polybutadiene was not cured even after storage for 30 days and was excellent in storage stability.

  Sample 9 was subjected to measurement of notched Izod impact strength at −40 ° C. in the same manner as in Example 1. However, a large amount of bumps occurred in the obtained test piece.

[Reference Example] (Izod impact strength with EVOH alone)
A Kuraray Eval L101 (EVOH with an ethylene content of 27 mol%, a saponification degree of 99.7 mol%, and an intrinsic viscosity of 1.1 dL / g at 30 ° C in hydrous phenol) was fed to a twin-screw segment type extruder with a screw diameter of 25 mmφ. Extrusion pelletization was performed under the following conditions.
Temperature condition (° C.): C1 / C2 / C3 / C4 / C5 / die = 220/220/220/220/220/220
Discharge rate: 2kg / h
Screw rotation speed: 115rpm

When the obtained pellet was measured for Izod impact strength with a notch at −40 ° C., the value was ² kJ / m ² .

2 is a molecular weight distribution curve of maleated cis-polybutadiene obtained in Example 1 and Comparative Example 1.

Claims (9)

A maleated thermoplastic resin in which a resin having a double bond in the main chain having a number average molecular weight of 15,000 to 100,000 is 0.1 to 3% by weight maleated, wherein at least a part of the maleic acid group is esterified Maleinized thermoplastic resin. The maleated thermoplastic resin according to claim 1, wherein substantially all maleic acid groups are esterified. In the resin having a double bond in the main chain, among the double bonds contained, the double bond existing other than the main chain is 10 mol of the total double bond amount of the resin having the double bond in the main chain. The maleated thermoplastic resin according to claim 1 or 2, which is not more than%. The maleated thermoplastic resin according to any one of claims 1 to 3, wherein the resin having a double bond in the main chain contains at least one of the structural units represented by the following structural formulas (I) and (II). .

The maleation according to any one of claims 1 to 4, wherein the resin having a double bond in the main chain is a ring-opening metathesis polymer of 1,4-cis polybutadiene, polyoctenylene, or a cyclic hydrocarbon containing a double bond. Thermoplastic resin. A method for producing a maleated thermoplastic resin, comprising reacting a resin having a double bond in a main chain with maleic anhydride in the presence of 300 to 3000 mol% of alcohol with respect to maleic anhydride. The method for producing a maleated thermoplastic resin according to claim 6, wherein the reaction is further performed in the presence of 3 to 30 times by weight of an organic solvent other than alcohol with respect to the resin having a double bond in the main chain. The production method according to claim 6 or 7, wherein the reaction is carried out under a pressure of 0.1 to 1.5 MPa. A thermoplastic resin containing 0.01 to 20% by weight of the ethylene-vinyl alcohol copolymer and the maleated thermoplastic resin according to any one of claims 1 to 5 based on the ethylene-vinyl alcohol copolymer. Composition.

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