JPS63175052A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition with excellent melt thermal stability capable of providing molded articles having improved mechanical properties, etc., and hardly any fisheye, by blending saponified ethylene-vinyl acetate copolymer with a specific amount of a polyamide based resin, etc. CONSTITUTION:A resin composition obtained by blending (A) saponified ethylene-vinyl acetate copolymer with 20-80mol.% ethylene content, >=90mol.% saponification degree of vinyl acetate component and 0.7-1.5dl/g intrinsic viscosity with (B) a polyamide based resin having number (I) of terminal carboxyl groups and number (II) of terminal groups expressed by the formula -CONRR' (R is 1-22C hydrocarbon; R' is H, etc.) satisfying the formula II/(I+ II)X100>=5 and (C) an alpha-olefinic ionomer resin at 98/2-2/98, preferably 95/5-10/90 weight ratio [(A)/(B)] of the components (A) to (B) and 2/98-50/50, preferably 2/98-30/70 weight ratio [(C)/(A)+(B)] of the components (C) to the total of the components (A) and (B).

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a resin composition suitable for deaf patients comprising a saponified ethylene-vinyl acetate copolymer, a specific polyamide resin, and an α-olefin ionomer resin. relating to things.

[Conventional technology]

In recent years, films that shrink with hot water or hot air have been used for food packaging, but the required characteristics are as follows:
It is said that it should have mechanical strength to maintain the shape of the contents, barrier properties to prevent rancidity and drying, good dimensional stability at room temperature, and high shrinkage at high temperatures.

As a composition for such a use, a composition comprising a saponified ethylene-vinyl acetate copolymer, a polyamide resin, and an α-olefin ionomer resin is known (Japanese Patent Application Laid-Open No. 1983-1987, 7JO!). rO), this composition had the disadvantage that it did not have sufficient melt thermal stability and often formed a gel-like substance, resulting in a large number of fish eyes in the film, etc.

[Purpose of the invention]

As a result of intensive research to solve such problems, the present inventors found that (I) saponified ethylene-vinyl acetate copolymer,
■ Number of terminal carboxyl groups (-000H) (A) and terminal -CONRR' group (where R is a hydrocarbon group with carbon number/--1, R' is a hydrogen atom or carbon number of carbon number !-, 2- A composition consisting of a lyamide resin (having a hydrogen group) and an α-olefin ionomer resin (GIr) has excellent melting thermal stability and does not cause problems such as the formation of gel-like substances over a long period of time, and can stably form fish eyes. The present invention was completed by discovering that it is possible to manufacture a product with less.

[Structure of the invention]

The saponified ethylene-vinyl acetate copolymer (I) used in the present invention has an ethylene content of 20 to tO mol%, preferably 43 to 60 mol%, and a degree of saponification of the vinyl acetate component of 9.
0 mol% or more, preferably 93 mol% or more is usually used. If the ethylene content is less than 20 mol %, the oxygen barrier properties at high humidity will decrease, while if it is more than 10 mol %, physical properties such as oxygen barrier properties and printability will deteriorate.

Furthermore, if the degree of saponification is less than 90 mol%, oxygen barrier properties and moisture resistance will decrease. Among these saponified products, the intrinsic viscosity (73%
(measured as a water-containing phenol solution at 30°C) is 0.7~
/, ,! t dlli, preferably O8g~/, ,
? dlli is preferably used in terms of the mechanical strength of the finished product.

In addition, the saponified copolymer may further contain small amounts of propylene, isobutyne, α-olefins such as α-octene, α-dodece/α-octadecene, unsaturated carboxylic acids or salts thereof, partial alkyl esters, complete alkyl esters, and nitrile. , amides, anhydrides, unsaturated sulfonic acids or salts thereof, and the like.

In addition, the (n) polyamide resin used in the present invention has the number (A) of terminal carboxyl groups (-cooH) and the terminal -0O
NRR' group (R is a hydrocarbon group with the number of carbon atoms/~ here, R' is a hydrogen atom or the number of carbon atoms/~ here carbonization≧3).

That is, the terminal carboxyl group of a polyamide obtained by polymerization or copolymerization of a lactam having three or more members, an ε-amino acid, or a dibasic acid and a diamine is modified with an N-substituted amide.

Usually, mono-substituted amide modification (H/ is a hydrogen atom) is practical, but di-substituted amide modification may also be used.

In order to produce the polyamide resin of the present invention, the polyamide raw material is: (1) carbon number/~, 2 monoamines, or (2) carbon number/~, 2 monoamines, or (2) carbon number/~
The -2- monoamine is polycondensed in the presence of a monocarboxylic acid having 1 to 23 carbon atoms.

Specifically, the raw materials for the polyamide include lactams such as C-caprolactam, enantholactam, capryllactam, lauryllactam, α-pyrrolidone, and α-piperidone, 6-aminocaproic acid, quaaminohbutanoic acid, and deaminocaproic acid. Nonanoic acid, 5-amino acids such as ll-aminoundecanoic acid, adipic acid, glutaric acid, pimelic acid, superic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecadionic acid, hexadecadioic acid, hexadecenedioic acid , eicosandionic acid,
Eicosadienedionic acid, diglycolic acid 1.2,2!
-) Limethyladibic acid, xylylene dicarboxylic acid, /
, lI-Dibasic acids such as cyclohexanedicarboxylic acid, terephthalic acid, inphthalic acid, hexamethylene diamine, tetramethylene diamine, nonamethylene diamine, undecamethylene diamine, dodecamethylene diamine, 221I (or cor"+")- Examples include diamines such as k''limethylhexamethylene diamine, bis-(a, ll'-aminocyclohexyl)methane, and metaxylylene diamine.

As the monoamine having carbon number/~2-, methylamine,
Ethylamine, propylamine, butylamine, pentylamine/, hexylamine, heptylamine, octylamine, -monoethylhexylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine , aliphatic monoamines such as octadecylamine, octadecylamine, eicosylamine, tocodylamine, cycloaliphatic monoamines such as cyclohexylamine, methylcyclohexylamine, aromatic monoamines such as benzylamine, β-phenylethylamine, N, Symmetrical secondary amines such as N-dimethylamine, N,N-diethylamine, N,N-dipropylamine, N,N-dibutylamine, N,N-diethylamine, N,N-dioctylamine, N2H-didecylamine, N-methyl-N-ethylamine, N-methyl-N
-fklamine, N-methyl-N-dodecylamine,
N-methyl-N-octadecylami! , N-ethyl-N-hexadecylamine 7, N-ethyl-N-octadecylamine, N-propyl-N-hexadecylamine, N-methyl-N-cyclohexylamine, N-methyl-N-benzylamine, etc. Examples include hybrid secondary amines.

In addition, monocarboxylic acids having 2 to 23 carbon atoms include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, capric acid, pelargonic acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid. acids, aliphatic monocarboxylic acids such as myristoleic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, arachidic acid, behenic acid, cycloaliphatic monocarboxylic acids such as cyclohexanecarboxylic acid, methylcyclohexanecarboxylic acid, Examples include aromatic monocarboxylic acids such as benzoic acid, toluic acid, ethylbenzoic acid, and phenylacetic acid.

In addition to the above monoamine or monoamine and monocarboxylic acid, if necessary, ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylene Diamine, undecamethylene diamine, dodecamethylene diamine, tridecamethylene diamine, hexadecamethylene diamine, octadecamethylene diamine, coy't'' (or co+'t-11I)
) Aliphatic diamines such as dibutylhexamethylene diamine, cyclohexane diamine, methylcyclohexane diamine, alicyclic cyamines such as bis-(4L,+'-aminocyclohexyl)methane, and aromatic diamines such as xylylene diamine. Diamines such as malonic acid, succinic acid, glutaric acid, adipic acid, Vimeri/@
, speric acid, azelaic acid, sebacic acid, undecanedio/dioic acid, dodecanedioic acid, tridecadionic acid, tetradecadionic acid, hexadecadioic acid, hexadecenedioic acid, octadecadionic acid, octademo/dioic acid,
Aliphatic dicarboxylic acids such as eicosandionic acid, eicosandionic acid, tocosandionic acid, 't24'-trimethyladipic acid, alicyclic dicarboxylic acids such as tercyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, 7 Dicarboxylic acids such as aromatic dicarboxylic acids such as tarlic acid and xylylene dicarboxylic acid may also be present.

The reaction for producing the polyamide resin of the present invention may be started using the polyamide raw materials described above according to a conventional method, and the carboxylic acid and amine may be added at any stage from the start of the reaction to the start of the reaction under reduced pressure. It can be added with. Moreover, the carboxylic acid and the amine may be added simultaneously or separately.

The amount of carboxylic acid and amine used is 7 mol of polyamide raw material (as the amount of carboxyl group and amino group)
Monomer or monomer unit constituting the repeating unit) 1
mol) to 1 mol of co-omeq, preferably 1 mol of 3-/9 meq (the equivalent weight of the amine group is
The amount of amine group that reacts with 1 equivalent of carboxylic acid and 2 liters to form an amide bond is defined as /equivalent.

If this amount is too small, it becomes impossible to produce a polyamide resin having the effects of the present invention. On the other hand, if it is too large, it becomes difficult to produce a polyamide with high viscosity, and the physical properties of the polyamide resin are adversely affected.

Further, the reaction pressure is preferably 100 Torr or less, preferably 300 Torr or less at the end of the reaction. If the pressure at the end of the reaction is high, the desired relative viscosity cannot be obtained. There is no disadvantage to having low pressure.

The reaction time under reduced pressure is preferably 0.3 hours or more, usually 7 to 1 hour.

-CONRR that the polyamide resin of the present invention has at the terminal
The hydrocarbon group represented by R or R' in ' group includes methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, -monoethylhexyl group, nonyl group, decyl group. , undecyl group, dodecyl group, tridecyl group, tetradecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, octadecyl group, eicosyl group,
Aliphatic hydrocarbon groups such as tocosyl group, alicyclic hydrocarbon groups such as cyclohexyl group, methylcyclohexyl group, cyclohexylmethyl group, phenyl group, tolyl group,
Examples include a benzyl group, a β-phenylethyl group), and an aromatic hydrocarbon group.

100NRR' of terminal -000H group of polyamide resin
The conversion ratio to -COOH groups is controlled by the presence of amines or amines and carboxylic acids during the production of polyamide resins, but in the present invention, the extent of this conversion is -COOH
3 mol% or more of the group, preferably 10 mol% or more vb;
-comRx' group, and the amount of unconverted E000H group is so μe
q/, 9 Polymer or less, preferably lIoμeq/
, 9.Polymer or less is desirable. If the degree of this conversion is small, the effects of the present invention cannot be expected. On the other hand, increasing the degree of conversion is not disadvantageous in terms of physical properties, but it makes production difficult, so it is best to limit the amount of unmodified terminal carboxyl groups to /μsq/,9. It's a good idea.

The hydrocarbon groups represented by R and R' in the -CONRR' group are obtained by hydrolyzing the polyamide resin using hydrochloric acid.
Measured by gas chromatography. -coon group is obtained by dissolving the polyamide resin in benzyl alcohol and adding 0.
Measured by titration with IN caustic soda.

As the terminal group of the polyamide resin, the above-mentioned 100N
In addition to the RR/ groups, there are 1000T1 groups and -N- groups derived from the polyamide raw materials mentioned above.

The terminal amino group may be modified or unmodified, but is preferably modified with the above-mentioned hydrocarbon because of its good fluidity and melt thermal stability.

-NH2 group dissolves polyamide resin in phenol,
Measure by titration with 0.03N hydrochloric acid.

The relative viscosity of the polyamide resin of the present invention is (ηrel),
Follow 4t10 to J Engineering 8! The concentration in t% sulfuric acid/%, measured at a temperature of 5°C, is -6, preferably -5. If the relative viscosity is too low, it will be difficult to form into strands and chips, which will be inconvenient in manufacturing. On the other hand, if it is too high, moldability will deteriorate.

QII) α-olefin ionomer resin in the present invention refers to an ionic copolymer in which a copolymer of an α-olefin and an α,β unsaturated carboxylic acid derivative is crosslinked with metal ions. Here, α-olefins include ethylene, propylene, etc., α, β unsaturated carboxylic acid derivatives, and °C are acrylic acid, methacrylic acid, itaconic acid, methyl acrylate, ethyl acrylate,
Examples include methyl methacrylate and ethyl methacrylate. In addition, as a metal ion, the valence is 7 to 1.
For example, Na, Mg, Zn, etc. can be mentioned.

The mixing ratio of the saponified ethylene-vinyl acetate copolymer (I) and the above-mentioned polyamide resin (n) is not particularly limited, but is usually (I)/(II) = 9x71-279 on a weight basis.
g, preferably 9315 to 10/oO.

At 9 t/g or more, the effect of improving physical properties such as improving the street repair strength of the ethylene-vinyl acetate copolymer cyanide is not observed, while at less than 9 t/g, the effect of improving the oxygen barrier properties of the polyamide resin cannot be obtained. do not have.

α-olefin ionomer resin (m) and etele/
- The mixing ratio of the saponified vinyl acetate copolymer (I) and the total amount of the polyamide resin (n) is usually determined on a weight basis (LI
r)/(I) + (n) =ko/qt-go/! 0,
Preferably it is 2/deg~, yo/dg. If the α-olefin ionomer resin is too small, mechanical strength and dimensional stability will decrease. On the other hand, if the amount is too large, the barrier properties will be impaired.

The composition of the present invention can be formed into vents, films, etc. by melt forming.
It is molded into various molded products such as sheets, containers, and rods. As the melt molding method, known molding means such as extrusion molding, blow molding, injection molding, etc. are employed.

The melt molding temperature is in the range of 1zo22a0°C, more specifically, the temperature at the extruder discharge part - 224t.

It can be selected from ℃, screw compression part temperature/SO ~ 30℃.

The resin composition of the present invention may contain well-known additives such as various stabilizers, fillers, pigments, dyes, lubricants, antiblocking agents, and various thermoplastic resins.

〔Example〕

Next, the composition of the present invention will be explained in more detail with reference to Examples.

Example of manufacturing polyamide resin Six types of polyamide resins were manufactured using the following method.

2001j autoclave, 6-caglolactam t
oe, water/coni, and the amounts of monoamines and carboxylic acids shown in Table 1 below, the temperature was raised to 260°C in a sealed nitrogen atmosphere, the reaction was carried out under pressure for 1 hour with stirring, and then gradually and reduce the pressure to the pressure shown in Table 1 below,
The reaction was carried out under reduced pressure for several hours.

After the pressure was restored to normal pressure by introducing nitrogen, stirring was stopped and the strands were taken out and made into chips. Unreacted monomers were extracted and removed using boiling water and dried.

Relative viscosity of the obtained polyamide resin, amount of terminal -coou groups, number of terminal -NH2 groups and terminal -〇〇〇H groups (A)
and the number 0 of the terminal -0ONR'R group (■/1■7×1OO, mol %) are shown in Table 1.

Examples/~7 and Comparative Examples/~C The polyamide resin produced in the above production example, an ethylene-vinyl acetate copolymer having an ethylene content of 31 mol% and a saponification degree of the vinyl acetate component of 97 mol%. (manufactured by Nippon Gosei Kagaku ■, trademark: Soarnol J!iT), and α- which is a zinc neutralized product of ethylene-methacrylic acid copolymer.
Olefin-based ionomer resin (manufactured by Mitsui Polychemicals ■, trademark: Surlinna/6!θ) was triblended in the proportions shown in Table 2 below, and a +oH da extruder with a T-die (manufactured by Ikesu Iron Works ■, l5-IIO) was used. mold), extrusion temperature 2/IO
℃, screw rotation speed, ii Q rpm and thickness 30μ
A film was produced.

Five hours after the start of film formation, the film was sampled using Laser Eye (manufactured by Yasuyo Denki ■) and the results are shown in Table 2 below.

Table 2 [Effects of the Invention] The composition of the present invention has extremely good melting thermal stability, and when molded into a molded product, it has excellent mechanical properties, gas resistance, and dimensional stability, and there is no problem such as fish eyes. Molded products can be manufactured.

Claims (3)

[Claims] (1) (I) Saponified ethylene-vinyl acetate copolymer (II) Number of terminal carboxyl groups (-COOH) (A) and terminal -CONRR' group (where R is a hydrocarbon having a carbon number/~22) group, R' represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms) and the number (B) satisfies (B)/(A)+(B)×100≧5. A resin composition comprising a resin and (III) an α-olefin ionomer resin. (2) The weight mixing ratio of (I) and (II) is (I)/(I
The resin composition according to claim 1, wherein I)=98/2 to 2/98. (3) The weight mixing ratio of (III) and (I) + (II) is (I
The resin composition according to claim 1 or 2, wherein II)/{(I)+(II)}=2/98 to 50/50.