Note: Descriptions are shown in the official language in which they were submitted.
2~7~i12
SPECIFICA~ION
THEI~OPLASTIC RESI~ COMPOSITIO~ AND P~ODUCTION METHOD T~DEREOF
TECHNOLOGY FIELD
The present invention relates to a thermoplastic
composition comprising a modified polyolefin polymer and a
polyamide and to production method thereof, more particularly, to
a thermoplastic resin composition having excellent compatibility,
mechanical property and heat resistance and to production method
thereof.
BACKGROUND OF THE INVE~TIO~
Recently, an attempt to obtain a resin composition having
the both features of a polyolefin resin and a polyamide resin by
blending the above both resins has been noted to improve the
mechanical property, heat resistance, dyeability and paintability
of the polyolefin resin and to improve the anti-hygroscopicity
and deterioration of properties due to the hygroscopicity of the
polyamide resin. However, the compatibility between the
polyolefin resin and the polyamide resin is generally low,
accordingly the resin obtained by simple blending, for example,
by molten kneading of the both resins has poor mechanical
strength and bad surface properties because of poor compatibility
between the both resins.
A method to modify a polyolefin resin by copolymerization
~q~7r~ ~
of a polyolefin and an unsaturated carboxylic acid anhydride has
been known9 in order to improve the compatibility between the
above both resins. ~s the unsaturated carboxylic acid, maleic
acid anhydride and the homologues thereof may be used. For
example, Japanese Laid-Open Patent Publication No.60-177073
discloses a method for producing an improved resin composition by
graft-polymerization of an unsaturated carboxylic acid ~o a
polyolefin resin. Further, Japanese Laid-Open Patent Publication
No.62-241938 discloses a method for producing a resin composition
comprising a polyolefin modified by an unsaturated carboxylic acid,
a polyolefin, a polyamide and a metallic compound.
Thus, in conventional modified polyolefin resin, as a
modifying agent, maleic acid anhydrides and the homologues
thereof have been used. However, in the resin composition
produced by using such modified polyolefin resins, the sufficient
improvement of characteristics has not always been observed,
requiring the more improvement of characteristics for practical
use.
The object of the present invention is the improvement of
characteristics of resin compositions obtained by using a new
modifying agent instead of maleic acid anhydrides and the
homologues thereof.
DISCLOSURF. O~ THE INVENTION
The present invention, in the first aspect, is to provide a
thermoplastic resin composition comprising
2 ~ ~ 7 J ~ h
(A)1 100 weight parts.of modified polyolefin polymer having
one structural unit of a glycidyl group represented by the
following general formula (I) per 2-1,000 repeating units of
olefin:
~~\
H-C-H
I ~I)
R-C-C-NHC~ -Ar
l 11
~~~
where Ar represents an aromatic hydrocarbon group 6-23 in carbon
number having at least one glycidyloxy group, and R represents a
hydrogen atom or a methyl group, and
(B)100 weight parts of a polyamide.
The present invention is, in the second aspect, to provide
a method for producing the aforementioned thermoplastic resin
composition characterized by molten kneading of the above both
components (A~ and (B).
BEST MODE FOR PRACTICING THE INVENTION
The modified polyolefin polymer as the component (A) has
one structural unit of a glycidy]. group represented by the
following general for~ula (I) per 2-1,000 repeating units~
preferably 5-200 repeating units of olefin:
H-C-H
(r
R-C-C-NHC~ -Ar
11
\ ~
where formula, Ar represents an aromatic hydrocarbon group 6-23 in
carbon number having at least one glycidyloxy group and R
represents a hydrogen atom or a methyl groupO It is an important
constituent element of the present inYention and it derives from
a compound with functional groups, so-called a modifying agent
having at least one acryl amide group and a glycidyl group,
respectively. The acryl amide group also includes, besides acryl
amide group, methacryl amid group.
As to such modifying agent, there is no particular
structural limitation if it has acryl amide group and glycidyl
group, but preferred is a compound represented by the general
formula (III):
C~ =C-C-N~C~ -Ar
I ll ~III)
R O
where Ar and R are the same as in the general formula (I).
Such compounds can be manufactured by a method described in
Laid-open Patent Publication No. 60-130580. That is, it is
obtainable by condensing an aromatic hydrocarbon having at least
one phenolic hydro~yl group with N-methylol acrylamide or N-
~ ~3 ~ r~ ~ ~
methylol methacrylamide in the presence of an acidic catalyst andthen by glycidyli~ation of the hydroxyl group by the use of
epihalohydrin. As the aforementioned aromatic hydrocarbon having
at least one phenolic hydro~yl group, a phenol compound, 6-23 in
carbon number is used. ~s specific examples of the
aforementioned phenolic compound, there may be included phenol,
cresol, xylenol, carbachlor, thymol, naphthol, resorcin,
hydroquinone, pyrogarol and phenantrol. Of these compounds, most
preferred ~ay be a mono-valent phenol having alkyl substitution
group. When, for e~ample, 2,6-xylenol and N-methylol acryl amide
are used as starting materials, a compound represented by the
following structural formula ~IY) will be obtained:
CH3
CH2=CHCNHC~ ~ OCH2CHCH2 (IV)
Il ~ \/
O CH3 O
When ortho-cresol and N-methlol acryl amide is used as
starting materials, the resultant compound will be of the
following structural formula (V):
~ CH3
CH2=CHCNHCH2 ~ (V)
OCH2CHCH2
o
The amide bond in the structural unit of the general
formula (1) improves not only dyeability and paintability, but
V~ lr~/
affinity with a polyamide, while the glycidyl group contributes
to an improvement of mechanical strength, heat resistance and
compatibility of the resin composition through the possible
reaction with an active hydrogen. If the proportion of the
structural units having a glycidyl group represented by the
general formula (I) is less than the aforementioned proportion,
no sufficient properties-improving effect is obtainable, while if
this proportion is too high, it is not preferable, either, since
the thermoplasticity inherent in the resln composition is lost.
Thus, it is necessary that the modified polyolefin polymers of
the present invention contain one structural unit having glycidyl
group of the aforementioned general formula (I) per 2-1,000,
preferably 5-200 repeating units of olefin.
The structural unit havi~g a glycidyl group represented by
the general formula (I) is exemplified by one represented by the
following formula (II):
H-C-H CHb
H-C-C-NHCH2 ~ O ~ OCH2CHC~ (II)
11 ~ \/
O C~ _~
_
In the modified polyolefin polymers of the present
invention9 the structural unit represented by the general formula
(I) may possibly exist at random or regularly blockwise, or may as
1 2
well exist at the end of the-molecule or as graft. There is no
particular limitation for the molecular weight of the modified
polyolefin polymers comprising polyethylene, polypropylene et
cetera, but preferably it may be in a range of 3,000-1,000,000 and
more preferably 10,000-500~000. When a polydiene is used as a
starting material, there is practically no limitation for its
molecular weigh~ and selection may be made from those low to high
in molecular weight. The polydiene used may be 1, 2-polymer or as
well be cis- or ~rans-1, 4-polymer. The diene unit of the
resulting modified polydiene type polymers may again be 1, 2-
polymerization or cis- as well as trans-l, 4 polymerization.
There is no particular limitation about the method for
manufacturing the modified polyolefin polymers but the following
two methods may be particularly suitable.
The first of these two methods is the so-called polyolefin
resin graft modification method, in which two components of a
polyolefin (a) and a modifying agent (b) having a glycidyl group
represented by the aforementioned general formula ~III) are
subjected to radical addition by the use of a radical
polymerization initiator (c~. In this reaction, a proper solvent
for dissolving or swelling polyolefins such as tetralin, decalin,
toluene, xylene or chlorobenzen may be used. It is also possible
to cause a polyolefin resin to react in the molten state by the
use of an extruder, kneader, heating roller and the like without
using solvent.
~ ~ ~J 7 3 ~ ~
There is no limitation about the polymerization initiator
used and common radical initiators may be used. For example,
peroxides such as cumene hydroperoxide, tertiary
butylhydroperoxide, benzoyl peroxide, lauroyl peroxide, decanoyl
peroxide and acetyl peroxide or azo compounds such as
azobisisobutyronitrile may be used alone or in combination of two
or more.
The second manufacturing method is to cause an olefin
monomer ~o copolymerize with a modifying agent represented by the
aforementioned general formula (III). There is no particular
limitation about the copolymerization method and, besides common
radical polymerization method, cationic polymerization method and
anionic polymerization method, coordination polymerization method
by the use of a transition metat and the like are also feasible.
As the polyolefins or olefin monomers used in the present
invention, there may be included ethylene, propylene9-l-butene,
l-pentene, iso-butene et cetera; homopolymers thereof; conjugate
dienes such as butadiene, isoprene, chloroprene and phenyl
propadiene; homopolymers of such conjugate dienes; cyclic dienes
such as cyclopentadiene, 1, 5-norbornanediene, 1, 3-cyclohexadiene,
1, 4-cyclohexadiene, 1, 5-cyclooctadiene and 1, 3-cyclooc~adiene;
homopolymers of these cyclic dienes; a, ~-nonconjugate dienes,
etc. Random copolymers and block copolymers of olefins with vinyl
compounds, etc., to say nothing of these olefins each other, are
usable.
~ ~ 9 7 ~ ~ 2
The component (B), a polyamide used in the present
invention is called ~ylon ~ and those having repeating units
of acid amide bond (-CONH-) may be unrestrictedly used. By the
form of polymerization, there are: (lt ring-opening
polymerization of lactams, (2) reaction of aliphatic diamines
with at least one compound selected from the group consisting of
aliphatic dicarboxylic acids~ acid anhydrides thereof and acid
halides thereof, and (3) condensation polymerization of
aminocarboxylic acids.
As concrete examples, there are polycaprolactam (Nylon-6),
polyhexamethylene adipamide (Nylon-66), Nylon-610, Nylon-12,
Nylon-9 and Nylon-ll. Also copolymers or mixtures of two or more
of the foregoings may be acceptable.
As a method for producing the resin composition of the
present invention, there is, for e~xample, a method wherein the
above modified polyolefin polymer (A) and the polyamide (B) are
molten kneaded. In molten kneading, known equipment may be used.
For example, there are a heating roll, an extruder, Bunbury
mixer and Bravender. Temperature for melting and power re~uired
for kneading may be appropriately adjusted depending upon the
molecular weight of a resin used.
The mixing ratio of the modified polyolefin polymer (A) and
the polyamide (B) is l~ lO0 weight parts of the component (A) to
lO0 weight parts of the component (B). The component (A) less
than l weight part lowers mechanical properties including impact
2~'WJ~
resistance. On the other hand, the component (A) more than 100
weight parts lowers the heat resistance inherent in the polyamide.
To the resin composition of the present invention, if
necessary, a catalyst to allow the modified polyolefin resin (A)
to react with the polyamide (B) may be added. As such catalyst~
unrestrictedly, one or more of compounds to promote the reaction
of the amino group, amide group or carboxylic group with the
glycidyl group may be selected.
Further, to the resin composition of the present invention,
if necessary, heat stabilizers, ultraviolet ray obsorbers,
antioxidants, fillers, antistatics agents, lubricants, coloring
agents, flame retarders, and organic or inorganic reinforcing
agents may be added.
The present invention will be explained by means of the
following examples, but the invention is not restricted by these
examples.
In the following description, part and ~ indicate
weight part and weight % respectively, unless otherwise
indicated.
Further, the graft quantity indicates the weight % of the
modifying agent contained in the modified polyolefin, and the
graft reaction rate indicates the rate (weight %) of the
modifying agent reacted with the polyolefin in the modifying agent
used for modifying the polyolefin.
1 n
23Q,~1 2
Reference ~xample 1 : Synthesis of modifying agent
A mixture of 102.6 parts of 4-acrylamidomethyl-2,6-
dimethyl- phenol, 181 parts of epichlorohydrin, and 2~27 parts of
benzyl- triethylammonium chloride was stirred at lOO~C for 30
minutes. To the reaction mixture cooled to 50 C , 147 parts of
5-N sodium hydroxide was added dropwise in 10 minutes under
stirring, then the mixture was stirred at 45 ~ 50C for 1 hour.
To the mixture cGoled to room temperature, 120 parts of
methyl isobutyl ketone and 500 parts of water were added and
separated. The organic layer was washed 3 times with 300 parts of
water, dehydrated with anhydrous sodium sulfate, then the solvent
was vacuum distilled off to gain N-[4-(2,3-epoxypropoxy)-3,5 di-
methylphenylmethyl]acrylamide. The epoxy equivalent measured by
JIS-K7236 was 271, and the melting point was 90~ 92C .
Reference Example 2 : Synthesis of modified polyolefin polymer (A-1)
To 100 parts of low density polyethylene (Sholex-M171 of
Showa Denko Co., Ltd. hereinafter abbreviated as LDPE) of 7g/10
min. of melt-flow rate measured by JIS-K6760, 7 parts of the
modifying agent obtained in the above Reference Example 1 and 0~1
part of a ,a '-bis(t-butylperoxy-m-isopropyl)benzene (Perbutyl-P of
Nihon-yushi Co.~ Ltd.) were mixed at ordinary temperature. The
mixture was fed into a two axes extruder (PCM-30 of Ikegai Steel
Co., Ltd.) fixed to 220 C at a rate of 4 kg/hr. The extruded
reaction mixture was cooled with water to be pelletized, then the
~97~ ~
pellets were dried under reduced pressure at 80 C for 3 hours.
The dried pellets thus obtained were dissolved into xylene
heated to 120 C , and the xylene solution was added dropwise to
acetone and the modified resin was reprecipitated to remove an
unreacted modifying agent and a homopolymer of the modifying agent.
From the elementary analysis value of the nitrogen atom
contained in the modified resin after reprecipitation and the
analysis value of epoxy group by FT-IR method, the graft quantity
of the modifying agent was 5.8~ and the graft reaction rate was
89%.
The modified olefin polymer had one structure unit derived from
the compound of the formula (rV) per 96 repeating units of
olefin.
. .
Reference Example 3 : Synthesis of modified polyolefin polymer (A-2)
To 100 parts of ethylene-propylene copolymer (EP02P of
Japan Synthetic Rubber Co., Ltd. hereinafter abbreviated as EPR)
of 3.2g/10 min. of melt-flow rate in case of a 2.2 kg load at 230
C , 10 parts of the modifying agent obtained in the above
Reference Example 1 and 0.1 part of a ,a '-bis(t-butylperoxy-m-
isopropyl)benzene (Perbutyl-P of ~ihon-yushi Co., Ltd.3 were mixed
at ordinary temperature. The mixture was fed into a two axes
extruder (PCM-30 of Ikegai Steel Co., Ltd.) fixed to 220 C at a
rate of 4 kgthr. The extruded reaction mixture was cooled with
water to be pelletized, then the pellets were dried under reduced
1 2
2 ~ 2
pressure at 80 C for 3 hours.
The dried pellets thus obtained were dissolved into xylene
heated to 120 C , and the xylene solution was added dropwise to
acetone and the modified resin was reprecipitated to remove an
unreacted modifying agent and a homopolymer of the modifying agent.
- From the elementary analysis value of the nitrogen atom
contained in the modified resin after reprecipitation and the
analysis value of epoxy group by FT-IR method, the graft quantity
of the modifying agent was 7.2% and the graft reaction rate was
79%.
The modified olefinic polymer had one structure unit
derived from the compound of the formula (rV) per 79 repeating
units of olefin.
Reference Example 4 : Synthesis of modified polyolefin polymer (A-3)
To 100 parts of polypropylene (~oblen-H501 of Sumitomo
Chemical Industrial Co., Ltd. hereinafter abbreviated as PP) of
3.5g/10 min. of melt-flow rate measured by JIS-K67589 5 parts of
the modifying agent obtained in the above Reference Example 1 and
0.1 part of a ,a '-bis(t-butylperoxy-m-isopropyl)benzene (Perbutyl-
P of ~ihon-yushi Co., Ltd.) were mixed at ordinary temperature.
The mixture was fed into a two axes extruder (PCM-30 of Ikegai
Steel Co., Ltd.) fixed to 210 C at a rate of 4 kg/hr. The
extruded reaction mixture was cooled with water to be pelletized,
then the pellets were dried under reduced pressure at 80C for 3
2 ~ ~ 7 3 1 ~ ,
hours.
The dried pellets thus obtained were dissolved into xylene
heated to 120C , and the xylene solution was added dropwise to
acetone and the modified resin was reprecipitated to remove an
unreacted modifying agent and a homopolymer of the modifying agent.
From the elementary analysis value of the nitrogen atom
contained in the modified resin after repre,cipitation and the
analysis value of epoxy group by FT-IR method, the graft quantity
of the modifying agent was 3~57 and the graft reaction rate was
73%.
The modified olefin polymer had one structure unit from the
compound of the formula (IV) per 122 repeating units of olefin.
Examples 1~ 3 ---
Each of mixtures of polyamide (Amylan CM1026 of Toray Co.,
Ltd.) and the modified polyolefin polymers (A-l), (A-,2) and (A-3)
obtained in the Reference Examples 2~ 4 mixed at ordinary
temperature in the ratio shown in Table l was fed into a two axes
extruder (PCM-30 of Ikegai Steel Co., Ltd.) fixed to 230 C at a
rate of 5 kg/hr. The extruded reaction product was cooled with
water to be pelletized, then the pellets were dried under reduced
pressure at 120 C for 15 hours to produce a pelletized resin
composition.
Comparative Examples 1~ 4
2 ~ ~ 7 ~ ~ ~
The polyamide only used in the above examples or each of
the mixtures of polyamide and polyolefin (LDPE, EPR and PP) mixed
at ordinary temperature in the ratio shown in Table 1 was fed into
a two axes extruder (PCM-30 of Ikegai Steel Co., Ltd.) fixed to
230 C at a rate of S kg/hr. The extruded product was cooled with
water to be pelletized, then the pellets were dried under reduced
pressure at 120C for 15 hours to produce a pelletized resin
composition.
The pelletized resin compositions (dried under reduced
pressure at 120C for lS hours) produced in the above Examples 1
~ 3 and Comparative Examples 1~ 4 were injection molded by a
injection molding machine (IS80EP~-2A of Toshiba Co., Ltd.) fixed
at 230C of the cylinder temperature to prepare test pieces. Each
test piece was tested for Izod impact strength with notch and
surface unevenness by the following method. The results are
shown in Table 2.
Izod impact strength with notch :
In accordance with the measurement method specified by JIS-
K7110, the test was conducted with fixing the temperature of the
test piece and atmosphere at test to 23 C .
Surface unevenness :
The surface unevenness of injection molded pieces was
judged by visual inspection based on the following criteria:
O : All the surface is even and good.
~ : Flash is observed near the gate.
~ C~ 7 ~ 1 2
x : Flash is observed over all the surEace.
Table 1
Rec in Composition
Polyamide Modified polyolefin polymer
PartsKind Parts
Examples 1 1 0 0 Modified PE (A-l~1 0
2 1 0 0 Modified EPR (A-2)2 0
3 1 0 0Modified PP (A-3) 5 0
Comp. 1 1 0 0 0
Examples 2 1 0 0P E 1 0
3 1 0 0E P R 2 0
4 I 0 0P P 5 0
Table 2
Impact strength Surface .
(kgf23Occm/cm) unevenness
Examples 1 18.0 O
2 28.3 O
3 8.0 O
Comp. 1 6.0 O
Examples 2 10.6
3 17.4 x
4 7.5 x
~ 7 ~ 3
POSSIBILITY OF INDVSTRIAL APPLICATIO~
The present invention provides the strong affinity in the
interface between a polyolefin and a polyamide, and provides a
composition giving molded articles, having good mechanical
properties such as impact resistance and good surface properties.
Making use of such characteristics, the resin composition of the
invention has wide industrial applications for molded articles as
well as fiber and film. By injection, extrusion, blow and
compression molding used for ordinary thermoplastic resins,
desired molded articles can be obtained. These molded articles
are useful as various mechanical, electric and electronic parts.
