Vinyl alcohol copolymer having terminal amino group

A vinyl alcohol copolymer having a terminal amino group and comprising 1-90 mol % of vinyl alcohol units and 10-90 mol % vinyl monomers selected from the group consisting of olefins, acrylamides, methacrylamides, vinyl ethers, nitriles, vinyl halides, and vinylidene halides, said copolymer having at least one terminal amino group is useful for preparing resin compositions having good gas barrier properties.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to vinyl alcohol copolymers having a terminal 
amino group and having good reactivity. 
The present invention further relates to resin compositions having good 
mixing dispersibility. 
2. Description of the Prior Art 
Known vinyl alcohol polymers having a terminal functional group are 
polyvinyl alcohol having a terminal hydroxyl group via sulfide bond and 
one having a terminal alkyl group via sulfide group (Japanese Patent 
Application Laid-open Nos. 105410/1982 and 187003/1984). However, 
polyvinyl alcohol having a terminal hydroxyl group or terminal alkyl group 
could not give resin compositions having good mixing dispersibility with 
thermoplastic resins. Polyvinyl alcohol having a terminal amino group via 
sulfide bond is also known (WO 91/15518). The polyvinyl alcohol having a 
terminal amino group, however, could not give, when kneaded with 
thermoplastic resins, resin compositions having good gas barrier 
properties. Block copolymer of polyacrylic acid and polyvinyl alcohol 
linked via sulfide bond is known (Japanese Patent Application Laid-open 
No. 189113/1984). This block copolymer, however, is poor in mixing 
dispersibility with thermoplastic resins and hence could not give, when 
kneaded with thermoplastic resins, resin compositions having good gas 
barrier properties. Also known is polyvinyl alcohol having side chains of 
0.5 to 30 molt of hydrazide group. This polyvinyl alcohol however has low 
crystallinity, thereby tending to have low water resistance, and could not 
give, when kneaded with thermoplastic resins, resin compositions having 
good gas barrier properties. 
Vinyl alcohol polymers alone exhibit insufficient flexibility and 
mechanical properties and, to improve this, blending with other 
thermoplastic resins such as polyolefins has been practiced. On the other 
hand, thermoplastic resins alone, such as a polyolefin alone, do not have 
sufficient gas barrier properties and, to improve, blending with vinyl 
alcohol polymer has been conducted. However, vinyl alcohol polymer has 
poor affinity with and dispersibility in thermoplastic resins such as 
polyolefin, so that shaped articles and films comprising a blend of the 
above have markedly decreased mechanical properties or transparency. 
To solve the above problems, Japanese Patent Application Laid-open No. 
202638/1988 discloses a process which comprises blending an ethylene-vinyl 
alcohol copolymer having a terminal alkyl group and a polyolefin, and 
Japanese Patent Application Laid-open No. 88837/1991 discloses a process 
comprising blending an ethylene-vinyl alcohol copolymer and an polyolefin 
having introduced epoxy group. These processes, however, produce only 
small improvement effect and it has been desired to further improve 
dispersibility, transparency and mechanical properties of these blends. 
SUMMARY OF THE INVENTION 
Accordingly, an object of the present invention is to provide a vinyl 
alcohol copolymer having any degree of polymerization selected from a 
range of low degree of polymerization to high degree of polymerization and 
having a highly reactive amino group introduced into an end thereof. More 
specifically, the object is to provide a vinyl alcohol copolymer having a 
terminal amino group, said vinyl alcohol copolymer being capable of 
giving, when melt kneaded with a thermoplastic resin having functional 
groups reactive with said amino group, a resin composition having good 
mixing dispersibility. 
Another object of the present invention is to provide a resin composition 
comprising a vinyl alcohol polymer and a thermoplastic polymer other than 
vinyl alcohol polymers and being capable of giving films and like shaped 
articles having good dispersibility and excellent mechanical properties. 
As a result of intensive study to solve the above problem, the present 
inventors have found a vinyl alcohol copolymer having a terminal amino 
group and comprising 1 to 90 mol % of vinyl alcohol units, 0 to 89 mol % 
of vinyl ester units and 10 to 90 mol % of units from an ethylenically 
unsaturated monomer copolymerizable with the vinyl ester and completed the 
invention (hereinafter this copolymer is referred to as "the first 
invention"). 
Also, the present inventors have found a resin composition comprising a 
vinyl alcohol polymer (A) having a terminal amino group and a 
thermoplastic resin composition having functional groups reactive with 
said amino group and completed the invention (hereinafter this resin 
composition is referred to as "the second invention").

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The first invention is described at first. 
The amino group that constitutes the terminal group of the present 
invention should be a primary amino group (--NH.sub.2) or a secondary 
amino group (imino group: .dbd.NH), of which the former is preferred. 
Concrete examples of the terminal group having amino group are those 
represented by the following formula 
##STR1## 
wherein R.sup.1 represents a group selected from the following three: 1) a 
hydrocarbon group which may have amino group or hydroxyl group, 
2) a hydrogen atom and 
3) an amino group, 
and R.sup.2, R.sup.3 and R.sup.4 each represents a hydrogen atom or a lower 
alkyl group, under the condition of either R.sup. having an amino group or 
at least one member of R.sup. and R.sup.2 being a hydrogen atom. 
Concrete examples of R.sup.1 in the formula (I) are lower alkyl groups, 
e.g. methyl group, ethyl group, propyl group, butyl group, isobutyl group, 
octyl group, dodecyl group and octadecyl group; lower alkylene groups, 
e.g. 2-propenyl group and 3-butenyl group; lower alkyl groups having aryl 
group, e.g. benzyl group and phenylethyl group; lower alkyl groups which 
may be interrupted by oxygen and having a primary, secondary or tertiary 
amino group, e.g. 2-aminoethyl group, 4-aminobutyl group, 6-aminohexyl 
group, 12-amindodecyl group, 2-(2-aminoethylamino) ethyl group, 
2-aminoethoxyethyl group, 2-(2-(2-aminoethylamino)-ethylamino)ethyl group 
and dimethylaminoethyl group; lower alkyl groups having a hydroxyl group, 
e.g. 2-hydroxyethyl group and 3hydroxypropyl group; primary, secondary or 
tertiary amino groups, e.g. amino group, methylamino group, dimethylamino 
group and phenylamino group and hydrogen atom. Where R.sup.1 is a 
hydrocarbon group or one with functional group, the number of the carbon 
atoms of the hydrocarbon group is preferably not more than 20, more 
preferably not more than 10. 
Examples of R.sup.2 are hydrogen atom and lower alkyl groups having not 
more than 10 carbon atoms, e.g. methyl group, ethyl group, propyl group 
and butyl group. R.sup.2 may be linked with R.sup.1 via covalent bond, the 
concrete examples cyclic alkylene groups having 3 to 8 carbon atoms, e.g. 
cyclic butylene. 
Examples of R.sup.3 and R.sup.4 are hydrogen atom and lower alkyl groups 
having not more than 10 carbon atoms, e.g. methyl group, ethyl group, 
propyl group, butyl group, pentyl group and hexyl group. 
Part other than the terminal group of the present invention comprises a 
monovalent copolymer comprising 1 to 90 mol % of vinyl alcohol units, 0 to 
89 mol % of vinyl ester units and 10 to 90 mol % of units from an 
ethylenically unsaturated monomer (hereinafter this part other than the 
terminal group is sometimes referred to as "monovalent copolymer"). 
Examples of vinyl ester units are units from vinyl formate, vinyl acetate, 
vinyl propionate, vinyl pivalate, vinyl butyrate, vinyl valerate, vinyl 
caprate, vinyl benzoate and vinyl trifluoroacetate, among which preferred 
is vinyl acetate from commercial viewpoint. 
Examples of units from ethylenically unsaturated monomer (hereinafter 
referred to as "comonomer") are olefins, e.g. ethylene, propylene, 
1-butene and isobutene; acrylamide derivatives, e.g. acrylamide, 
N-methylacrylamide, N-ethylacrylamide, N,N-dimethylacrylamide, 
acrylamidepropanesulfonic acid or salts thereof, 
acrylamidepropyldimethylamine, salts thereof or quaternary salts thereof; 
methacrylamide derivatives, e.g. methacrylamide, N-methylmethacrylamide, 
N-ethylmethacrylamide, methacrylamidepropanesulfonic acid or salts 
thereof, methacrylamidepropyldimethylamine, salts thereof or quaternary 
salts thereof; vinyl ethers, e.g. methyl vinyl ether, ethyl vinyl ether, 
n-propyl vinyl ether, i-propyl vinyl ether, t-butyl vinyl ether, dodecyl 
vinyl ether and stearyl vinyl ether; nitriles, e.g. acrylonitrile and 
methacrylonitrile; vinyl or vinylidene halides, e.g. vinyl chloride, 
vinylidene chloride, vinyl fluoride and vinylidene fluoride; allyl 
compounds, e.g. allyl acetate and allyl chloride; vinylsilyl compounds, 
e.g. vinyltrimethoxysilane; isopropenyl acetate and N-methylpyrrolidone. 
Preferred among these comonomer units are olefin units, in particular 
ethylene units. 
The content of vinyl alcohol units in the monovalent copolymer is 1 to 90 
mol %, preferably 30 to 80 mol %, more preferably 40 to 75 mol %. The 
content of vinyl ester units is 0 to 89 mol %, preferably 0 to 50 mol %, 
more preferably 0 to 30 mol %. That is, the vinyl ester units may not be 
contained. 
The monovalent copolymer is obtained by solvolysis of a copolymer having 
vinyl ester units. The degree of hydrolysis of the vinyl ester units is 
preferably 1 to 100 mol %, more preferably 20 to 100 mol %, still more 
preferably 50 to 100 mol %, yet more preferably 80 to 100 mol %, yet more 
preferably 95 to 100 mol % and most preferably 99 to 100 mol %. The 
content of the comonomer units is 10 to 90 mol %, preferably 20 to 70 mol 
%, more preferably 25 to 60 mol %. 
Preferable among the above monovalent copolymers are olefin-vinyl alcohol 
copolymers, in particular ethylenevinyl alcohol copolymers. Where the 
monovalent copolymer is an ethylene-vinyl alcohol copolymer, it is 
desirable that the contents of constituting units other than vinyl alcohol 
units, vinyl ester units and ethylene units be as small as possible and, 
concretely, not more than 10 mol %, more preferably not more than 5 mol %. 
There are no specific restrictions with respect to the degree of hydrolysis 
of the vinyl alcohol copolymer having a terminal amino group of the 
present invention. It is, however, desirable that the copolymer have an 
intrinsic vismolt, cosity as determined in a 85/15 by weight mixed solvent 
of phenol/water (hereinafter referred to as "water-containing phenol") at 
30.degree. C. (hereinbelow, the intrinsic viscosity means that obtained on 
vinyl alcohol copolymer having a terminal amino group or vinyl ester 
copolymer having a terminal amino group) of 0.05 to 10 deciliters/g 
(hereinafter abbreviated as "dl/g"), more preferably 0.2 to 10 dl/g. If 
the intrinsic viscosity is less than 0.05 dl/g, the features of vinyl 
alcohol copolymer will sometimes not be developed. If the intrinsic 
viscosity exceeds 10 dl/g, efficiency of introduction (blocking 
efficiency) of a functional group comprising amino group will, depending 
on reaction conditions, sometimes decrease. 
Where the monovalent copolymer is a polymer consisting only of vinyl 
alcohol units (including units from unhydrolyzed vinyl ester) and units 
from an olefin, it is desirable that the copolymer have an intrinsic 
viscosity of 0.5 to 3 dl/g, more preferably 0.7 to 2 dl/g. 
The amino group introduced into the end of the monovalent copolymer of the 
present invention is preferably introduced into only the end (preferably 
one end). Where the amino group is also introduced into the side chains 
other than the end, the resulting copolymer has reduced crystallinity and 
tends to decrease its water resistance. The content of the amino group in 
the side chains of the monovalent copolymer is therefore preferably not 
more than 0.5 mol %, more preferably not more than 0.3 mol %, most 
preferably not more than 0.1 mol %. 
The process for producing the vinyl alcohol copolymer having a terminal 
amino group of the present invention is now described. 
As a result of an intensive study on processes for producing the vinyl 
alcohol copolymer having a terminal amino group of the present invention, 
the present inventors have found 2 processes. 
The first process comprises reacting a copolymer comprising vinyl alcohol 
units and having a terminal ester bond with a primary or secondary amine 
or ammonia. This process is suitable for producing vinyl alcohol 
copolymers having a terminal amino group and having a degree of hydrolysis 
of at least 50 mol %. The copolymer comprising vinyl alcohol units and 
having a terminal ester bond is obtained by the successive steps of 
copolymerizing a vinyl ester and a comonomer to obtain a copolymer 
comprising vinyl ester units, solvolyzing the obtained copolymer and 
treating the solvolyzed product with an acid. Vinyl esters having no 
hydrogen atom on the a .alpha.-position of the carbonyl group in the ester 
bond are polymerized in a solvent represented by the following formula 
(II) 
##STR2## 
wherein R.sup.3, R.sup.4 and R.sup.5 are each as defined for the same, 
respectively, in the formula (I) . 
A vinyl ester represented by the following formula (III) is polymerized in 
a solvent or without solvent, and preferably without solvent or in a 
solvent represented by the above formula (II) 
##STR3## 
wherein R.sup.3 and R.sup.4 are as defined for the same in formula (I) . 
Examples of the vinyl ester represented by the above formula (III) are 
vinyl acetate, vinyl propionate, vinyl butyrate and vinyl isobutyrate. 
The vinyl ester units and comonomer units mentioned in the description of 
the monovalent copolymer also exemplify those constituting the copolymer 
having vinyl ester units. Where units from a monomer having carboxylic 
group or functional group convertible to carboxylic group or having ester 
bond such as lactone ring are present in the main chain other than the end 
of the copolymer having vinyl ester units, their content in the copolymer 
having vinyl ester units is smaller the better, since they may possibly 
cause amino groups to be introduced into the side chains of the monovalent 
copolymer. Thus, the content of units from such a monomer is preferably 
less than 0.5 mol %, more preferably less than 0.3 mol % and most 
preferably less than 0.1 mol %. 
There are no specific restrictions with respect to the conditions of 
solvolysis of the copolymer having vinyl ester units, but solvolysis with 
an alkaline catalyst, in particular methanolysis with a catalyst of NaOH, 
KOH, CH.sub.2 ONa or CH.sub.3 OK is desirable. The amount of the alkaline 
catalyst used for the solvolysis is preferably in an amount of 0.02 to 200 
moles based on 100 moles of the vinyl ester units in the copolymer. The 
solvolysis temperature is preferably in a range of from room temperature 
to 120.degree. C. The obtained copolymer having vinyl alcohol units may 
have any degree of hydrolysis of vinyl ester units, but higher degree of 
hydrolysis is desirable for the purpose of suppressing consumption of the 
primary or secondary amine or ammonia due to reaction with the vinyl ester 
units that have not been hydrolyzed. Thus, the copolymer having vinyl 
alcohol units preferably has a degree of hydrolysis of at least 50 mol %, 
more preferably at least 95 mol %, most preferably at least 99 mol %. 
The copolymer having vinyl alcohol units can be acid-treated under any 
conditions, but it is desirable to conduct the treatment in a reaction 
solvent of an alcohol such as methanol, ethanol or ethylene glycol, in the 
presence of a catalyst such as sulfuric acid, hydrochloric acid, 
p-toluenesulfonic acid or acetic acid and at a temperature in a range of 
from room temperature to 150.degree. C. 
The obtained copolymer having vinyl alcohol units and a terminal ester bond 
is reacted with a primary or secondary amine or ammonia, among which 
preferred is a compound represented by the following formula (IV) 
##STR4## 
wherein R.sup.1 and R.sup.2 are each as defined for the same in formula 
(I). 
Examples of the primary or secondary amine represented by the above formula 
(IV) are, alkylamines, e.g. methylamine, dimethylamine, ethylamine, 
propylamine, butylamine, octylamine and stearylamine; unsaturated amines, 
e.g. allylamine and diallylamine; diamines, e.g. ethylenediamine, 
hexamethylenediamine and dodecamethylenediamine; polyamines, e.g. 
diethylenetriamine, 3,3'-diaminodipropylamine, triethylenetetramine, 
tetraethylenepentamine and pentaethylenehexamine; aminoalcohols, e.g. 
ethanolamine and 4-aminobutanol; cyclic amines, e.g. pyrrolidine, 
piperidine and morpholine and hydrazines, e.g. hydrazine, methylhydrazine, 
N,N-dimethylhydrazine and phenylhydrazine. Particularly preferred among 
these amines are primary amines in view of reactivity with the copolymer 
having vinyl alcohol units and a terminal ester bond. 
The conditions of reaction of the copolymer having vinyl alcohol units and 
a terminal ester bond with a primary or secondary amine or ammonia are 
suitably selected depending on the reactivity of the reactant. The amount 
of the primary or secondary amine or ammonia to be fed is selected from a 
range of from 2 times to large excess of the amount to be introduced into 
the copolymer having vinyl alcohol units. Usable solvents are alcohols, 
e.g. methanol and ethylene glycol; dimethylacetamide; N-methylpyrrolidone; 
dimethyl sulfoxide and the like. The reaction temperature is appropriately 
selected from a range of from room temperature to 200.degree. C. Use of a 
catalyst, such as an alkaline catalyst, e.g. NaOH, KOH, CH.sub.2 ONa and 
CH.sub.3 OK, or acid catalyst, e.g. acetic acid, hydrochloric acid and 
sulfuric acid can increase the reaction rate to a certain degree. 
The second production process comprises reacting a copolymer obtained by 
copolymerizing a vinyl ester and an ethylenically unsaturated monomer and 
having a degree of hydrolysis of 0 mol %, with a primary or secondary 
amine or ammonia, to produce the copolymer having vinyl alcohol units and 
a terminal amino group. This process is suitable for producing vinyl 
alcohol-based copolymers having a terminal amino group and having a degree 
of hydrolysis of 1 to 100 mol %, in particular for producing vinyl 
alcohol-based copolymers having a terminal amino group and having a degree 
of hydrolysis of 1 to 50 mol %. 
The vinyl esters and ethylenically unsaturated monomers (comonomers) 
mentioned in the description of the first production process are also 
usable here. 
The copolymer obtained by copolymerizing a vinyl ester and an ethylenically 
unsaturated monomer and having a degree of hydrolysis of 0 mol %, which 
has a terminal carboxyl group, reacts with a primary or secondary amine or 
ammonia, whereby the corresponding amino group is introduced into the end 
of the copolymer and, at the same time, the vinyl ester units in the main 
chain of the copolymer are hydrolyzed, to yield a vinyl alcohol copolymer 
having a terminal amino group. 
The feed ratio of the primary or secondary amine or ammonia to the 
copolymer having vinyl ester units with a degree of hydrolysis of 0 mol % 
is preferably 0.2 to 100 mol % based on the vinyl ester monomer units of 
the copolymer, more preferably 1 to 10 mol % on the same basis. 
Desirable solvents are those having high polarity, e.g. alcohols such as 
methanol, ethanol and propanol; dimethyl sulfoxide and 
N-methylolpryrrolidone, among which methanol is particularly preferred. 
The reaction temperature is preferably in a range of from room temperature 
to 100.degree. C. and the reaction time is preferably 10 minutes to 5 
hours. 
Where there is desired still higher degree of hydrolysis of the vinyl 
alcohol copolymer having a terminal amino group, it is achieved by further 
hydrolyzing by the usual process using alkaline catalyst or the like. 
Of the first and second processes, the first one is more preferable for 
producing vinyl alcohol copolymers having a terminal amino group and a 
degree of hydrolysis of 50 to 100 mol %. 
The vinyl alcohol copolymers having a terminal amino group of the present 
invention are usable as starting materials for producing graft polymers 
and block polymers and like purposes. The graft polymers and block 
polymers from this copolymer, which have good chemical stability against 
alkylation agents, oxidizing agents and the like, have high utility in 
many fields, such as paints, adhesives and compatibility-improving agents. 
According to the present invention, there are provided vinyl alcohol 
copolymers having any degree of polymerization ranging from low degree of 
polymerization to high degree of polymerization and having a terminal 
amino group. The vinyl alcohol copolymers having highly reactive amino 
group introduced into the end thereof, give, when melt kneaded with 
thermoplastic resins having functional groups reactive with the amino 
group, resin compositions having good mixing dispersibility and gas 
barrier properties. 
The second invention is described next. 
The vinyl alcohol polymer (A) having a terminal amino group used in the 
invention is a polymer having vinyl alcohol units in the main chain and 
having a terminal amino group. Among vinyl alcohol polymers having 
terminal amino group, those having a primary or secondary amino group 
substantially at the ends (preferably at one end) thereof. The vinyl 
alcohol polymers preferably have as small side chain amino groups as 
possible, since side chain amino groups cause, by crosslinking, viscosity 
increase, gel formation or like troubles. The content of side chain amino 
groups is therefore preferably less than 0.5 mol %, more preferably less 
than 0.3 mol %, most preferably less than 0.1 mol %. The primary or 
secondary amino group means a primary amino group or an alkyl-substituted 
secondary amino group and its examples include amino group, methylamino 
group, ethylamino group and butylamino group, as well as hydrazides, such 
as hydrazide group and N-methylhydrazide group, which have active amino 
groups in their structure. 
There are no specific restrictions with respect to the content of vinyl 
alcohol units in the vinyl alcohol polymer, but it is preferably 1 to 90 
mol %, more preferably 30 to 80 mol % and most preferably 40 to 75 mol %. 
Particularly preferred among the vinyl alcohol polymers are ethylenevinyl 
alcohol copolymers, in which the ethylene content is preferably 10 to 90 
mol %, more preferably 20 to 70 mol % and most preferably 25 to 60 mol %. 
Unhydrolyzed vinyl ester units in the vinyl alcohol polymer decreases the 
crystallinity of the polymer, and hence the degree of hydrolysis of the 
polymer is the higher the better. Thus, the degree of hydrolysis of the 
vinyl alcohol polymer is preferably 1 to 100 mol %, more preferably 20 to 
100 mol %, still more preferably 50 to 100 mol %, yet more preferably 80 
to 100 mol %, yet more preferably 95 to 100 mol % and most preferably 99 
to 100 mol %. 
Where the vinyl alcohol polymer is a copolymer, examples of the units other 
than vinyl alcohol units are vinyl ester units and comonomer units. 
Concrete examples of the vinyl ester units and comonomer units are the 
same as those mentioned in the description for the monovalent copolymer of 
the first invention. 
The vinyl alcohol polymer having a terminal amino group may have any melt 
index (measured at 190.degree. C. under a load of 2160 g), but it is 
preferably 0.1 to 100 g/10 min. Where the vinyl alcohol polymer has a melt 
index of less than 0.1 g/1O min and is not thermoplastic, it is desirable 
to adjust the MI up to an appropriate level by adding to the polymer a 
polyhydric alcohol plasticizer such as glycerine, diglycerine, 
triglycerine, ethylene glycol, triethylene glycol, polyethylene glycol or 
polypropylene glycol or mixtures of the foregoing. 
Among the vinyl alcohol polymers having a terminal amino group of the 
present invention, preferred are those which are by themselves 
thermoplastic without addition of any plasticizer and in particular the 
vinyl alcohol copolymers having a terminal amino group mentioned in the 
description of the first invention. 
The thermoplastic polymer (B) having functional groups reactive with amino 
group used in the present invention includes thermoplastic polymers having 
functional groups reactive with amino group, e.g. an epoxy group and acid 
anhydrides such as anhydrous ring and oxazoline ring. The thermoplastic 
polymer having functional groups reactive with amino group is obtained by 
copolymerizing a monomer having such functional group with an olefin 
monomer or vinyl monomer. Also available is a process which comprises 
grafting a monomer having the functional group to an olefin polymer or 
vinyl polymer using an initiator such as peroxide, heat, light, 
radioactive rays or the like. Examples of the monomer constituting the 
olefin or vinyl polymer are olefins, e.g. ethylene, propylene, 1-butene, 
3-methyl-1-butene, 1-hexene and 1-octene; vinyl esters, e.g. vinyl 
acetate, vinyl propionate and vinyl pivalate; acrylic acid esters, e.g. 
methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, octyl 
acrylate, dodecyl acrylate and 2-ethylhexyl acrylate; methacrylic acid 
esters, e.g. methyl methacrylate, ethyl methacrylate, butyl methacrylate, 
hexyl methacrylate, octyl methacrylate and dodecyl methacrylate; vinyl 
halides, e.g. vinyl chloride and vinyl fluoride and styrene derivatives, 
e.g. styrene and .alpha.-methylstyrene. Examples of the monomer having a 
functional group reactive with amino group are monomers having epoxy 
group, such as glycidyl methacrylate, glycidyl acrylate, allyl glycidyl 
ether and vinyl glycidyl ether; monomers of acid anhydrides, such as 
maleic anhydride and itaconic anhydride and monomers having oxazoline 
ring, such as 2-vinyloxazoline and 2-(4-vinylamino phenyl)oxazoline. The 
suitable amounts of these monomers to be fed vary depending on the 
reactivity of their functional groups. ,With the functional group being 
contained in too large an amount, gels tend to form, while too small a 
content produces little effect. The functional group equivalent is, 
although not specifically limited, preferably 500 to 200,000, and 500 to 
20,000 for epoxy group, 10,000 to 200,000 for acid anhydride and 500 to 
10,000 for oxazoline ring. The functional group equivalent means the 
amount in grams of resin containing 1 g-equivalent of the functional 
group. 
The thermoplastic polymer having functional group reactive with amino group 
may have any MI, but it is preferably 0.1 to 100 g/10 min, more preferably 
0.5 to 500 g/10 min and most preferably 0.5 to 100 g/10 min. 
The resin composition of the present invention comprises a vinyl alcohol 
polymer (A) having a terminal amino group and a thermoplastic polymer (B) 
having functional group reactive with the amino group. The incorporation 
ratio between component (A) and component (B) is in a range of 99:1 to 
1:99, preferably in a range of 95:5 to 5:95, more preferably in a range of 
95:5 to 30:70 and most preferably 95:5 to 45:55. 
The resin composition of the present invention, which comprises component 
(A) and component (B), may further contain a thermoplastic vinyl alcohol 
polymer (C) having no a terminal amino group and/or a thermoplastic resin 
(D) having no functional group reactive with amino group. Let, for 
instance, component (A) be an ethylene-vinyl alcohol copolymer having a 
terminal amino group, component (B) an ethylene-glycidyl methacrylate 
copolymer, component (C) an ethylene-vinyl alcohol copolymer and component 
(D) polyethylene. Then, to improve the gas barrier properties, resistance 
to solvents and warmth-keeping property polyethylene film, the composition 
is selected from a range of [(A)+(C)]:[(B)+(D)] of 5:95 to 45:5. Or, to 
provide ethylene-vinyl alcohol copolymer with flexibility and shock 
resistance, the composition is selected from a range of [(A) 
+(C)]:[(B)+(D)] of 55:45 to 95:5. In this case, it is more effective to 
blend component (A) with component (B) at first and then blending the 
obtained blend with component (C) and component (D). This prevents, even 
when the total content of component (A) and component (B) is only about 5% 
by weight or so, deterioration of properties due to poor dispersibility. 
The blending can be carried out by any known process such as one with 
Banbary mixer or melt blending with a single-screw or twin-screw extruder. 
Upon blending, there may be incorporated, within limits not to impair the 
function and effect of the present invention, other additives such as 
antioxidant, ultraviolet absorber, lubricant, plasticizer, antistatic 
agent and color. 
The resin composition of the present invention can readily be molded by 
known melt molding processes and be formed into optional shaped articles 
such as films, sheets, tubes or bottles. The resin composition further is 
usable, in combination with other thermoplastic resins, e.g. polyethylene, 
polypropylene, polyethylene terephthalate, polyamides and polystyrene, as 
a layer for multilayered laminates, which are formed by multi-layer 
co-extrusion, co-injection, extrusion coating or like known processes and 
used as various packaging materials. 
The resin composition of the present invention, comprising a vinyl alcohol 
polymer (A) having a terminal amino group and a thermoplastic resin (B) 
having functional group reactive with the amino group, gives films, 
sheets, containers and the like, which have far better mechanical 
properties, transparency and gas barrier properties than conventional 
compositions comprising a vinyl alcohol polymer and a thermoplastic resin 
and are hence suitably used in the fields of various packaging materials, 
molding materials and the like. 
Other features of the invention will become apparent in the course of the 
following descriptions of exemplary embodiments which are given for 
illustration of the invention and are not intended to be limiting thereof. 
In the Examples and Comparative Examples that follow, "%" means "% by 
weight" unless otherwise specified. 
EXAMPLES 
Synthesis Example 1 
Synthesis of ethylene-vinyl acetate copolymer 
An autoclave equipped with a stirrer, the air inside which had been 
sufficiently replaced by nitrogen, was charged with 905 g of vinyl 
acetate, 1,207 g of methyl acetate and 1.256 g of 
2,2'-azobisisobutyronitrile. The atmosphere in the vessel was then 
replaced by ethylene and ethylene was further introduced to make the 
internal pressure 14 kg/cm.sup.2 . The autoclave was then heated to a 
temperature of 60.degree. C., which caused to internal pressure to become 
29.5 kg/cm.sup.2. Five hours after the start of reaction, the autoclave 
was cooled to room temperature, to terminate reaction. The reaction 
mixture was reprecipitated from hexane and the obtained solid was dried 
with hot air at 40.degree. C. for 12 hours and then by vacuum drying at 
100.degree. C. for 12 hours, to give an ethylene-vinyl acetate copolymer 
having an ethylene content of 43 mol %. The yield was 33.7%. 
Synthesis Example 2 
Synthesis of ethylene-vinyl alcohol copolymer 
A separable flask equipped with a stirrer and a distillation column was 
charged with 338 g of the ethylene-vinyl acetate copolymer obtained in 
Synthesis Example 1 and 800 g of methanol. The separable flask was heated 
to a temperature of 65.degree. C. and 30 g of sodium hydroxide was added 
to conduct solvolysis of the ethylene-vinyl acetate copolymer, while the 
byproduct methyl acetate and methanol were being distilled off. One hour 
after the start of reaction, 30 g of sodium hydroxide was added again to 
permit the reaction to proceed for further 2 hours. The reaction mixture 
obtained was neutralized by addition of 150 g of acetic acid and the 
resulting mixture was reprecipitated from distilled water. The copolymer 
thus obtained was further washed sufficiently with distilled water and 
dried with hot air at 100.degree. C. for 5 hours and then by vacuum drying 
at 100.degree. C. for 12 hours, to give an ethylene-vinyl alcohol 
copolymer having an ethylene content of 43 mol % and a degree of 
hydrolysis of 99.5 mol %. 
Synthesis Example 3 
Synthesis of an ethylene-vinyl alcohol copolymer having ester bond at one 
end thereof 
An autoclave equipped with a stirrer was charged with 120 g of the 
ethylene-vinyl alcohol copolymer obtained in Synthesis Example 2, 500 g of 
methanol and 0.5 g of sulfuric acid, and reaction was effected at 
90.degree. C. for 2 hours. After completion of the reaction, the autoclave 
was cooled to 60.degree. C. and the 50 milliliters (hereinafter 
abbreviated as "ml") of a 10 % sodium acetate solution in methanol was 
added to the reaction mixture to neutralize it. The reaction mixture thus 
neutralized was reprecipitated from distilled water, to obtain a 
copolymer. The copolymer was washed well with distilled water and dried 
with hot air at 100.degree. C. for 5 hours and then vacuum-dried at 
100.degree. C. for 12 hours, to obtain an ethylene-vinyl alcohol copolymer 
having an ester bond at one end thereof and having an intrinsic viscosity 
as determined in water-containing phenol at 30.degree. C. of 0.507 dl/g, 
an ethylene content of 43 mol % and a degree of hydrolysis of 99.8 mol %. 
Example 1 
Synthesis of an ethylene-vinyl alcohol copolymer having hydrazide group at 
one end thereof 
A reaction vessel equipped with a stirrer was charged with 50 g of the 
ethylene-vinyl alcohol copolymer having an ester bond at one end thereof 
and obtained in Synthesis Example 3, 100 g of methanol, 20 g (0.4 mole) of 
hydrated hydrazine and 5 ml of a 2N sodium hydroxide solution in methanol, 
and reaction was effected at 65.degree. C. for 3 hours. After completion 
of the reaction, the vessel was cooled to room temperature and the 
reaction mixture was reprecipitated from distilled water. The copolymer 
gel obtained was washed well with distilled water, dried with hot air at 
100.degree. C. for 5 hours and vacuum-dried at 100.degree. C. for 12 
hours, to give an ethylene-vinyl alcohol copolymer having hydrazide group 
at one end thereof and having an intrinsic viscosity of 0.507 dl/g, an MI 
of 850 g/10 min, an ethylene content of 43 mol % and a degree of 
hydrolysis of 99.9 mol %. The hydrazide group at one end of the copolymer 
was trinitrophenyl-ized with trinitrobenzenesulfonic acid and the obtained 
product was subjected to quantitative determination for the amino group by 
spectrochemical analysis in ultraviolet and visible region. The amino 
group was found to be 6.1.times.10.sup.-5 equivalent/g. From this results 
on determination of amino group and from consideration of the reaction 
mechanism, the product was identified to be an ethylene-vinyl alcohol 
copolymer having a hydrazide group at one end thereof. 
Example 2 
Synthesis of an ethylene-vinyl alcohol copolymer having 
N-(2-aminoethyl)amide at one end thereof 
An autoclave equipped with a stirrer was charged with 100 g of an 
ethylene-vinyl alcohol copolymer having an ethylene content of 32 mol % 
and a degree of hydrolysis of 99.5 mol %, 400 g of methanol and 0.5 g of 
sulfuric acid, and reaction was effected at 60.degree. C. for 2 hours. To 
the reaction mixture, 60 g of ethylenediamine was added and reaction was 
further effected at 120.degree. C. for 4 hours. After completion of the 
reaction, the autoclave was cooled to room temperature and the obtained 
polymer gel was washed well with distilled water and pulverized. The 
powder thus obtained was washed again with distilled water, dried with hot 
air at 60.degree. C. for 10 hours and vacuum-dried at 100.degree. C. for 
12 hours, to give an ethylene-vinyl alcohol copolymer having 
N-(2-aminoethyl)amide at one end thereof and having an intrinsic viscosity 
as determined in water-containing phenol at 30.degree. C. of 1.07 dl/g, an 
MI of 1.6 g/10 min, an ethylene content of 32 mol % and a degree of 
hydrolysis of 99.8 mol %. The amino group at one end of the copolymer was 
determined in the same manner as in Example 1, to show 3.2.times.10.sup.-5 
equivalent/g. From this results on determination of amino group and from 
consideration of the reaction mechanism, the product was identified to be 
an ethylene-vinyl alcohol copolymer having an N-(2-aminoethyl)amide group 
at one end thereof. Example 3 
Synthesis of an ethylene-vinyl alcohol copolymer having N-butylamide at one 
end thereof 
A reaction vessel equipped with a stirrer was charged with 20 g of an 
ethylene-vinyl alcohol copolymer having undergone esterification of its 
molecular end in the same manner as in Synthesis Example 3 and having an 
ethylene content of 32 mol % and a degree of hydrolysis of 99.5 mol %, 50 
g of dimethyl sulfoxide and 30 g of butylamine, and reaction was effected 
at 80.degree. C. for 3 hours. After completion of the reaction, the vessel 
was cooled to room temperature and the reaction mixture was reprecipitated 
from distilled water. The product obtained was washed well with distilled 
water, dried with hot air at 100.degree. C. for 5 hours and vacuum-dried 
at 100.degree. C. for 12 hours, to give an ethylene-vinyl alcohol 
copolymer having N-butylamide at one end thereof and having an intrinsic 
viscosity as determined in water-containing phenol at 30.degree. C. of 
1.07 dl/g, an ethylene content of 32 mol % and a degree of hydrolysis of 
99.9 mol %. The obtained copolymer was subjected to 270 MHz NMR 
spectrometry in a 4/1 mixed deuterated methanol/heavy water at 80.degree. 
C. FIG. 1 shows the obtained NMR spectrum. FIG. 2 shows an enlarged view 
of a region of .delta.=2.0 to 2.7 ppm. From the results of the NMR 
spectrometry and from consideration of the reaction mechanism, the product 
was identified to be an ethylene-vinyl alcohol copolymer having an 
N-butylamide group at one end thereof. 
Example 4 
Synthesis of an ethylene-vinyl alcohol copolymer having 
N-(2-hydroxyethyl)amide at one end thereof 
A reaction vessel equipped with a stirrer was charged with 20 g of an 
ethylene-vinyl alcohol copolymer having undergone esterification of its 
molecular end in the same manner as in Synthesis Example 3 and having an 
ethylene content of 32 mol % and a degree of hydrolysis of 99.5 mol %, 50 
g of dimethyl sulfoxide and 30 g of ethanolamine, and reaction was 
effected at 80.degree. C. for 3 hours. After completion of the reaction, 
the vessel was cooled to room temperature and the reaction mixture was 
reprecipitated from distilled water. The product obtained was washed well 
with distilled water, dried with hot air at 100.degree. C. for 5 hours and 
vacuum-dried at 100.degree. C. for 12 hours, to give an ethylene-vinyl 
alcohol copolymer having an N-(2-hydroxyethyl)amide at one end thereof and 
having an intrinsic viscosity as determined in water-containing phenol at 
30.degree. C. of 1.07 dl/g, an ethylene content of 32 mol % and a degree 
of hydrolysis of 99.9 mol %. The obtained copolymer was subjected to 270 
MHz NMR spectrometry in a 4/1 mixed deuterated methanol/heavy water at 
80.degree. C. FIG. 3 shows the obtained NMR spectrum. FIG. 4 shows an 
enlarged view of a region of .delta.=2.0 to 2.7 ppm. From the results of 
the NMR spectrometry and from consideration of the reaction mechanism, the 
product was identified to be an ethylene-vinyl alcohol copolymer having an 
N-(2-hydroxyethyl)amide group at one end thereof. 
Example 5 
Synthesis of an ethylene-vinyl alcohol copolymer having hydrazide at one 
end thereof 
A reaction vessel equipped with a stirrer was charged with 50 g of the 
ethylene-vinyl alcohol copolymer with its end having undergone 
esterification in the same manner as in Synthesis Example 3 and having an 
ethylene content of 62 mol % and a degree of hydrolysis of 99.7 mol %, 100 
g of methanol, 20 g (0.4 mole) of hydrated hydrazine and 5 ml of a 2N 
sodium hydroxide solution in methanol, and reaction was effected at 
65.degree. C. for 3 hours. After completion of the reaction, the vessel 
was cooled to room temperature and the reaction mixture was reprecipitated 
from distilled water. The copolymer gel obtained was washed well with 
distilled water, dried with hot air at 100.degree. C. for 5 hours and 
vacuum-dried at 100.degree. C. for 12 hours, to give an ethylene-vinyl 
alcohol copolymer having a hydrazide group at one end thereof and having 
an intrinsic viscosity as determined in water-containing phenol at 
30.degree. C. of 0.64 dl/g, an ethylene content of 62 mol % and a degree 
of hydrolysis of 99.9 mol %. The amino group at one end of the copolymer 
was quantitatively determined in the same manner as in Example 1, and 
found to be 5.6.times.10.sup.-5 equivalent/g. From this results and from 
consideration of the reaction mechanism, the product was identified to be 
an ethylene-vinyl alcohol copolymer having a hydrazide group at one end 
thereof. 
Example 6 
Melt blending was conducted through Plastograph at 80 rpm and at a 
temperature of 200.degree. C. for 30 minutes. The materials blended above 
were 40 g of an ethylene-vinyl alcohol copolymer synthesized in the same 
manner as in Example 1 and having a hydrazide group at one end thereof and 
having an intrinsic viscosity as determined in water-containing phenol at 
30.degree. C. of 1.08 dl/g, an ethylene content of 32 mol % and a degree 
of hydrolysis of 99.9 mol % and an amide group content of 3.2 
.times.10.sup.-5 equivalent/g and 10 g of an ethylene-glycidyl 
methacrylate copolymer having a glycidyl methacrylate content of about 
10%. Then it was found that the ethylene-glycidyl methacrylate copolymer 
dispersed uniformly in the ethylene-vinyl alcohol copolymer having a 
hydrazide group at one end thereof. The average particle diameter of the 
dispersoid of the ethylene-glycidyl methacrylate copolymer was 0.154 
.mu.m. The obtained resin gave films having excellent transparency and 
excellent other film properties, thus proving its high utility. 
Comparative Example 1 
Example 6 was repeated except that an ethylene-vinyl alcohol copolymer 
having an intrinsic viscosity as determined in water-containing phenol at 
30.degree. C. of 1.08 dl/g, an ethylene content of 32 mol % and a degree 
of hydrolysis of 99.9 molt was used instead of the terminal 
hydrazide-containing ethylene-vinyl alcohol copolymer, to obtain a resin. 
In the resin, although the ethylene-glycidyl methacrylate copolymer 
dispersed in the ethylene-vinyl alcohol copolymer, the dispersoid had an 
average particle diameter of 0.35 .mu.m. The resin gave films having 
poorer transparency and poorer other film properties than those from the 
resin obtained in Example 6. 
Example 7 
Synthesis of an ethylene-vinyl alcohol copolymer having hydrazide group at 
one end thereof 
A reaction vessel equipped with a stirrer was charged with 76.6 g of an 
ethylene-vinyl acetate copolymer having an ethylene content of 43 mol % 
and 150 g of methanol and the mixture was heated at 50.degree. C. with 
stirring to dissolve. To the solution 15 g of hydrated hydrazine was added 
and reaction was effected at 50.degree. C. for 1 hour. After completion of 
the reaction, the vessel was cooled to room temperature and the reaction 
mixture was reprecipitated from distilled water. The copolymer obtained 
was washed well with distilled water and vacuum-dried at 50.degree. C. for 
12 hours, to give an ethylene-vinyl alcohol copolymer having a hydrazide 
group at one end thereof and having an intrinsic viscosity as determined 
in water-containing phenol at 30.degree. C. of 1.20 dl/g, an ethylene 
content of 43 mol % and a degree of hydrolysis of 3.0 mol %. The amino 
group at one end of the copolymer was quantitatively determined in the 
same manner as in Example 1, and found to be 3.2.times.10.sup.-6 
equivalent/g. From this results and from consideration of the reaction 
mechanism, the product was identified to be an ethylene-vinyl alcohol 
copolymer having a hydrazide group at one end thereof. 
Example 8 
Synthesis of an ethylene-vinyl alcohol copolymer having hydrazide group at 
one end thereof 
A reaction vessel equipped with a stirrer was charged with 10 g of the 
ethylene-vinyl alcohol copolymer obtained in Example 7 and having terminal 
amino group and 10 g of methanol, and the mixture was heated at 50.degree. 
C. with stirring to dissolve. To the solution 5 g of a 0.88% sodium 
hydroxide solution in methanol was added and reaction was effected at 
50.degree. C. for 30 minutes. After completion of the reaction, 0.2 g of 
acetic acid was added and the resulting mixture was added to distilled 
water to precipitate polymer. The polymer was washed well with distilled 
water and vacuum-dried at 50.degree. C. for 12 hours, to give an 
ethylene-vinyl alcohol copolymer having a hydrazide group at one end 
thereof and having an intrinsic viscosity as determined in 
water-containing phenol at 30.degree. C. of 1.10 dl/g, an ethylene content 
of 43 mol % and a degree of hydrolysis of 52 mol %. The amino group at one 
end of the copolymer was quantitatively determined in the same manner as 
in Example 1, and found to be 3.7.times.10.sup.-6 equivalent/g. 
Example 9 
Synthesis of an ethylene-vinyl alcohol copolymer having hydrazide group at 
one end thereof 
An autoclave equipped with a stirrer was charged with 100 g of an 
ethylene-vinyl alcohol copolymer synthesized in the same manner as in 
Synthesis Example 2 and having an ethylene content of 32 mol % and a 
degree of hydrolysis of 9.5 mol %, 400 g of methanol and 0.5 g of sulfuric 
acid and reaction was effected at 60.degree. C. for 2 hours. Then 25 g of 
hydrated hydrazine was added and reaction was effected at 120.degree. C. 
for 4 hours. After completion of the reaction, the autoclave was cooled to 
room temperature and the polymer gel that formed was washed well with 
distilled water and pulverized. The powder obtained was washed well with 
0.3 g/l aqueous acetic acid solution, dried with hot air at 60.degree. C. 
for 10 hours and vacuum-dried at 100.degree. C. for 12 hours, to give an 
ethylene-vinyl alcohol copolymer having a hydrazide group at one end 
thereof and having an intrinsic viscosity as determined in 
water-containing phenol at 30.degree. C. of 1.07 dl/g, an MI of 1.6 g/10 
min, an ethylene content of 32 mol % and a degree of hydrolysis of 99.9 
mol %. The amino group at one end of the copolymer was quantitatively 
determined in the same manner as in Example 1, and found to be 
3.2.times.10.sup.-5 equivalent/g. 
Example 10 
A blend was prepared from 80 g of the ethylene-vinyl alcohol copolymer 
having hydrazide group at one end thereof obtained in Example 9 and 20 g 
of an ethylene-glycidyl methacrylate copolymer having an glycidyl 
methacrylate content of 15% (i.e. functional group equivalent of 950) and 
an MI of 3 g/10 min. The blend was pelletized under the following 
conditions. 
Extruder used: Segment-type 25 mm-.phi. laboratory 2-screw extruder 
Type of screw: C (strong kneading type) 
Screw rotation: 230 rpm 
Output : 0.6 kg/h 
The pellets obtained were formed into 2 films having thicknesses of 25 
.mu.m and 100 .mu.m, respectively through a laboratory single-screw 
extruder at 220.degree. C. 
Comparative Example 2 
Example 10 was repeated except that as a thermoplastic vinyl alcohol 
polymer a conventional ethylene-vinyl alcohol copolymer having an ethylene 
content of 32 mol %, a degree of hydrolysis of 99.8 mol % and an MI of 1.6 
g/10 min was used. 
Comparative Example 3 
Example 10 was repeated except that there were used as a thermoplastic 
vinyl alcohol polymer a conventional ethylene-vinyl alcohol copolymer 
having an ethylene content of 32 mol %, a degree of hydrolysis of 99.8 mol 
% and an MI of 1.6 g/10 min and, as a thermoplastic polymer, a low density 
polyethylene having an MI of 3 g/10 min. 
Table 1 shows principal properties of the films obtained in Example 10 and 
Comparative Examples 2 and 3. As seen from the table, the films of Example 
10 are far superior in tensile strength and elongation, transparency and 
gas barrier properties, to those of Comparative Examples 2 and 3. 
TABLE 1 
______________________________________ 
Exam- 
ple Comp. Comp. 
Item Test method Unit 10 Ex. 2 Ex. 3 
______________________________________ 
Haze JIS K7105*.sup.1 
% 8.8 15 51 
Tensile 
ASTM D638*.sup.2 
Kg/mm.sup.2 
5.7 2.9 3.2 
strength 
Tensile 
ASTM D638*.sup.3 
Kg/mm.sup.2 
4.9 2.3 2.0 
strength 
Tensile 
ASTM D638*.sup.2 
% 305 300 270 
elon- 
gation 
Tensile 
ASTM D638*.sup.3 
% 340 170 3 
elon- 
gation 
Gas *4 cc .multidot. 20 .mu.m/ 
5.6 5.9 -- 
barrier m.sup.2 .multidot. day 
property 
______________________________________ 
Notes: 
*.sup.1 : With 100 .mu.m thick films 
*.sup.2 : With 25 .mu.m thick films in the machine direction 
*.sup.3 : With 25 .mu.m thick films in the transverse direction 
*4: A 25 .mu.m thick, unheattreated film specimen is conditioned at 
20.degree. C., 85% RH and then measured for oxygen transmission rate with 
OXTRAN 1050A made by Modern Control Co. 
Example 11 
There were melt kneaded under the following conditions 40 g of the 
ethylene-vinyl alcohol copolymer having hydrazide group at one end thereof 
obtained in Example 9 and 10 g of a methyl methacrylate-glycidyl 
methacrylate copolymer having an glycidyl methacrylate content of 10% 
(i.e. functional group equivalent of 1420 and an MI of 2 g/10 min. 
Machine used: Plastograph 
Shape of rotor: Roll type 
Rotation : 80 rpm 
Kneading temp.: 200.degree. C. 
Kneading time: 10 min 
The resin composition obtained was heat pressed at 220.degree. C. to form a 
film. The film was forced to break in liquid nitrogen. The plane of 
rupture was subjected to extraction treatment with xylene at 140.degree. 
C. and then observed with a scanning electron microscope. The film had 
excellent transparency and, from the microscopic observation, the average 
particle diameter of the dispersoid of the methyl methacrylate-glycidyl 
methacrylate copolymer was 0.2 82 m. 
Comparative Example 4 
Example 11 was repeated except that as a thermoplastic vinyl alcohol 
polymer a conventional ethylene-vinyl alcohol copolymer having an ethylene 
content of 32 mol %, a degree of hydrolysis of 99.8 molt and an MI of 1.6 
g/10 min was used. The average particle diameter of the dispersoid of the 
methyl methacrylate-glycidyl methacrylate copolymer was 0.5 .mu.m and the 
transparency of the film was worse than that of Example 11. 
Comparative Example 5 
Example 11 was repeated except that the materials used were as a 
thermoplastic vinyl alcohol polymer a conventional ethylene-vinyl alcohol 
copolymer having an ethylene content of 32 mol %, a degree of hydrolysis 
of 99.8 mol % and an MI of 1.6 g/10 min and, as a thermoplastic polymer, a 
polymethyl methacrylate having an MI of 2 g/10 min. The average particle 
diameter of the dispersoid of the polymethyl methacrylate was 3 .mu.m, 
which was bad. The transparency of the film was far inferior to that of 
the film of Example 11. 
Example 12 
There were melt kneaded under the following conditions 10 g of the 
ethylene-vinyl alcohol copolymer having hydrazide group at one end thereof 
and obtained in Example 1, 30 g of a conventional ethylene-vinyl alcohol 
copolymer having an ethylene content of 43 mol % and an MI of 5 /g10 min 
and 10 g of a methyl methacrylate-glycidyl methacrylate copolymer having 
an glycidyl methacrylate content of 10% (i.e. functional group equivalent 
of 1420) and an MI of 30 g/10 min. 
Machine used: Plastograph 
Shape of rotor: Roll type 
Rotation : 80 rpm 
Kneading temp.: 200.degree. C. 
Kneading time: 10 min 
The resin composition obtained was heat pressed at 220.degree. C. to form a 
film. The film was broken in liquid nitrogen. The plane of rupture was 
subjected to extraction treatment with xylene at 140.degree. C. and then 
observed with a scanning electron microscope. The film had good 
transparency and, from the microscopic observation, the average particle 
diameter of the dispersoid of the methyl methacrylate-glycidyl 
methacrylate copolymer was 0.3 .mu.m. 
Comparative Example 6 
The procedure of Example 12 was followed with 10 g of the ethylene-vinyl 
alcohol copolymer obtained in Synthesis Example 2, 30 g of a conventional 
ethylene-vinyl alcohol copolymer having an ethylene content of 43 mol % 
and an MI of 5 g/10 min and 10 g of a methyl methacrylate-glycidyl 
methacrylate copolymer having an glycidyl methacrylate content of 10% 
(i.e. functional group equivalent of 1420) and an MI of 30 g/10 min, to 
prepare a film. The average particle diameter of the dispersoid of the 
methyl methacrylate-glycidyl methacrylate copolymer was 0.8 .mu.m and the 
transparency of the film was worse than that of Example 12. 
Example 13 
There were melt kneaded under the following conditions 40 g of the 
ethylene-vinyl alcohol copolymer having a hydrazide group at one end 
thereof and obtained in Example 9 and 10 g of an oxazoline-modified 
polystyrene having an oxazoline content as converted to a functional group 
equivalent of 2200 and an MI of 5.0 g/10 min. 
Machine used: Plastograph 
Shape of rotor: Roll type 
Rotation : 80 rpm 
Kneading temp.: 200.degree. C. 
Kneading time: 30 min 
The resin composition obtained was heat pressed at 220.degree. C. to form a 
film. The film was broken in liquid nitrogen. The plane of rupture was 
subjected to extraction treatment with xylene at 140.degree. C. and then 
observed with a scanning electron microscope. From the microscopic 
observation, the average particle diameter of the dispersoid of the 
oxazoline-modified polystyrene was 0.4 .mu.m. 
Comparative Example 7 
Example 13 was repeated except that as a thermoplastic vinyl alcohol 
polymer a conventional ethylene-vinyl alcohol copolymer having an ethylene 
content of 32 mol %, a degree of hydrolysis of 99.8 mol % and an MI of 1.6 
g/10 min was used. The average particle diameter of the dispersoid of the 
oxazoline-modified polystyrene was 1 .mu.m. 
Example 14 
The procedure of Example 12 was followed with 10 g of the ethylene-vinyl 
alcohol copolymer having a 2aminoethylamide group at one end thereof and 
obtained in Example 2, 30 g of a conventional ethylene-vinyl alcohol 
copolymer having an ethylene content of 32 mol %, degree of hydrolysis of 
99.8 mol % and an MI of 1.6 g/10 min and 10 g of a [maleic 
anhydride-modified styrene]-[hydrated polyisoprene]-[styrene] block 
copolymer having a functional group equivalent of 35,000, a styrene 
content of 35%, a hydration ratio of 98.5% and an MI of 2 g/10 min, to 
prepare a film. The average particle diameter of the dispersoid of the 
[maleic anhydride-modified styrene]-[hydrated polyisoprene]-[styrene] 
block copolymer was 0.2 .mu.m. 
Comparative Example 8 
Example 14 was repeated except that the materials used were, as a 
thermoplastic vinyl alcohol polymer, 40 g of a conventional ethylene-vinyl 
alcohol copolymer having an ethylene content of 32 mol %, a degree of 
hydrolysis of 99.8 mol % and an MI of 1.6 g/10 min and, as a thermoplastic 
polymer, 10 g of a [maleic anhydride-modified styrene]-[hydrated 
polyisoprene]-[styrene] block copolymer having a functional group 
equivalent of 35,000, a styrene content of 35% , a hydration ratio of 
98.5% and an MI of 2 g/10 min, to prepare a film. The average particle 
diameter of the dispersoid of the [maleic anhydride-modified 
styrene]-[hydrated polyisoprene]-[styrene] block copolymer was. 0.8 .mu.m. 
Obviously, numerous modifications and variations of the present invention 
are possible in light of the above teachings. It is therefore to be 
understood that within the scope of the appended claims, the invention may 
be practiced otherwise than as specifically described herein.