JPH07103302B2 - Polymer composition - Google Patents

Description

FIELD OF THE INVENTION This invention relates to polymeric compositions suitable for melt molding processing.

2. Description of the Related Art Aromatic polyesters are used in various molding materials because of their excellent mechanical and physical properties. In particular, due to its excellent dimensional stability, it is widely used for die-casting various metals, such as aluminum and zinc, and sealing materials for IC elements. However, the aromatic polyester has a high melting temperature and a high viscosity at the time of melting, so that its application is limited. For example a thin sheet (for example
There is a problem that the polymer viscosity is too high to produce 0.2 mm), the flow on the mold becomes slow, and the solidification speed is prioritized, so that a satisfactory sheet cannot be obtained. In recent years, thinner sealing materials for IC elements have been demanded, and the above problems are particularly important. The melt viscosity can be lowered to some extent by raising the temperature, but there is a limit because it may cause deterioration of the polyester due to high temperature or deterioration or damage of an object such as an IC element depending on the application. A method is often employed in which the processing temperature is kept constant and the melt viscosity is lowered to increase the shear rate or decrease the degree of polymerization. The method of increasing the shear rate cannot be applied to all cases due to other molding processing conditions and equipment restrictions, and lowering the degree of polymerization necessarily lowers the mechanical properties of the polymer, especially the strength. It is not preferable because it causes

It is also conceivable to mix two or more kinds of polymers in order to reduce the polymer melt viscosity, but usually, polymers of the same series (in the case of aromatic polyesters, other aromatic polyesters) are mainly mixed. However, the mixing of different polymers is considered to inevitably bring about changes in the physical properties of the polymer, and has not been attempted so much. Moreover, even if a small amount of a different polymer that does not impair the physical properties of the main polymer is mixed with the main polymer, the viscosity does not usually decrease so much in reality.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention An object of the present invention is to provide a polymer composition in which the mechanical properties of an aromatic polyester are maintained substantially as they are, or further improved, and only the melt viscosity thereof is reduced. To do.

Means for Solving the Problems The present invention relates to aromatic polymer 70 to 9 for all polymer components.
A polymer composition containing 9.9% by weight and 30 to 0.1% by weight of a polyolefin, wherein the aromatic polyester may have a substituent, paraoxybenzoic acid [I], and optionally a 2-hydroxynaphthoene. Acids [I
I], an aromatic diol [III], and an aromatic dicarboxylic acid [IV], which are random copolymers, wherein the polyolefin is an olefin selected from the group consisting of ethylene, propylene, butene, and 4-methylpentene, either alone or as a copolymer. It relates to a polymer composition that is a united body.

The aromatic polyester that can be used in the present invention includes (1)
A homopolymer or copolymer of an aromatic compound monomer having a hydroxyl group and a carboxyl group in one molecule is used as an essential component, and if desired, (2) an aromatic compound having two hydroxyl groups in one molecule and one molecule Is a polyester containing a copolymer with an aromatic compound having two carboxyl groups.

Preferred monomer components used in the aromatic polyester of the present invention are selected from the following groups. Of course, other monomers may be used in combination therewith, but the amount thereof is preferably 5 mol% or less of the total amount of monomers.

Paraoxybenzoic acids having an amount represented by: 2-hydroxy-6-naphthoic acid having a group represented by: [wherein X and X'are each independently a hydrogen atom,
Halogen atom (eg chlorine, bromine, iodine, fluorine, etc.),
Lower alkyl which may have a side chain, for example methyl,
Ethyl, n-propyl, isopropyl, n-butyl, se
c-butyl, t-butyl, etc.), lower alkoxy group (eg, methoxy, ethoxy group, etc.), phenyl group, benzyl group, phenoxy group]; -O-Ar-O- having a group represented by [III] Aromatic diols, aromatic dicarboxylic acids having a group represented by -OOC-Ar'-COO- [IV] [In the formula, Ar and Ar 'are each independently the following general formula: (Wherein X and X ′ have the same meanings as described above and Q is O, -CH ₂ -, or -O (CH ₂ CH ₂₎ represents a group) represented by _{n O- (n = 1~4)]} .

These aromatic compounds may have a substituent such as halogen, lower alkyl, alkoxy and phenyl group on the aromatic nucleus, and may have a hydroxyl group and / or a carboxyl group on the same aromatic nucleus. Alternatively, they may be separately provided on two different aromatic nuclei existing in the same molecule. Preferably, two hydroxyl groups present in one molecule, 2
It is preferable that each of the carboxyl groups or the hydroxyl group and the carboxyl group is in the p-position (in the case of a naphthalene ring, the 2,6-position or the 1,4-position).

In this case, the total amount of monomers of [I] and [II] is [I],
It is 5 to 95 mol%, more preferably 10 to 90 cell% of the total amount of [II], [III] and [IV], and [I] and [I]
The molar ratio of [I] is preferably 4: 1 to 1: 4. Particularly, it is preferable that the monomer of [II] is in the range of 5 to 20 mol%, particularly 15 to 20 mol% of the total amount of [I], [II], [III] and [IV].

The above-mentioned monomer is preferably a random copolymer of the monomers constituting each group.

A polyester obtained from a monomer having such a constitution has liquid crystal properties, and when blended with a polyolefin, the melt viscosity is remarkably lowered.

The solution viscosity of the aromatic polyester used in the present invention is 1 to 1
It is 0, preferably 2-9.

The polyolefin that can be used in the present invention is a homopolymer or copolymer of ethylene, propylene, butene, and 4-methylpentene. Particularly preferred polyolefins are poly-4-methylpentene, polyethylene and the like.

Some polyolefins have a low thermal decomposition temperature (for example, polyethylene, polypropylene, etc.), but in that case, heat stabilizers such as phenolic antioxidants and phosphoric acid antioxidants may be added. .

The molecular weight of the polyolefin used in the present invention is 5,000 to 2
00,000, particularly 10,000 to 100,000 is preferable.

The polymer composition of the present invention may be blended with other polymers such as polyacetal, polyamide and polyacrylate in order to improve the properties required depending on its use, but the aromatic polyester in the polymer composition Of the total polymer component is 70% by weight or more, and the polyolefin content is 0.1% by weight or more. Particularly preferably, the aromatic polyester in the composition consisting of the aromatic polyester and the polyolefin is in the range of 90 to 99.9% by weight, and the polyolefin is in the range of 10 to 0.1% by weight.

If the amount of the polyolefin exceeds 10% by weight, the mechanical properties of the aromatic polyester, particularly mechanical strength and dimensional stability, may be impaired. On the other hand, if it is less than 0.1% by weight, the characteristic of viscosity decrease (improvement of fluidity) at the melting temperature is not sufficiently exhibited.

When the polyolefin is gradually blended with the aromatic polyester, the viscosity is drastically lowered than the viscosity predicted from the melt viscosity of each. This tendency is particularly remarkable when a small amount of polyolefin such as 10% by weight or less, particularly 5% by weight or less is blended.

Within the blending range, the mechanical strength of the aromatic polyester is hardly reduced, the fluidity is improved, and the heat resistance and the stability of dimensional accuracy are not impaired.

Further, when the amount of the polyolefin added is 5% by weight or less, the impact resistance of the polymer composition of the present invention is improved more than that of the raw material aromatic polyester.

The blend of two polymers in the present invention can be mixed and dispersed without causing significant phase separation. The composition of the present invention can be used as a film, a fiber and a molding resin, but is particularly useful as a molding resin having a complicated shape and an industrial fiber.

The composition obtained by the present invention can be mixed with solid fillers and reinforcing materials of various shapes to prepare a molding compound, and various moldings can be molded using this compound. Such a molding compound is prepared by blending two polymers of the present invention into pellets, and the pellets are blended with about 1 by weight.
˜70%, preferably 10-50% (by weight to the composition) of various shapes of solid filler and / or reinforcement are compounded. For example, glass fibers, carbon fibers, aluminum fibers, fibrous whisker-like substances made of potassium titanate and other inorganic substances, as filler, calcium silicate,
Inorganic substances of various shapes such as silica, talc and mica, and fluorine-containing organic polymers such as polytetrafluoroethylene are used. The mixing is carried out in the temperature range of about 250 to 350 ° C. using an extruder, preferably an extruder with a degassing port, in the same temperature range as that which forms the shape of the shaped fibers and the like.

The molded product obtained from the composition of the present invention can be heat-treated in an inert atmosphere. This blended polymer is useful as a molding resin, particularly suitable for molding thin materials due to its high fluidity, and is also used for producing coatings, fibers and films. These can be molded by injection molding and can be processed by melt extrusion techniques such as melt spinning and melt film formation.

Examples 1 and 2 2-acetoxy-6-naphthoic acid 17 mol% (97.8 gr),
Para-acetoxybenzoic acid 64.74mol% (291.5gr), hydroquinone diacetate 9.13mol% (52.1gr) and terephthalic acid 9.13mol% (37.9gr) were melted and polymerized for 20 hours while gradually heating and deacetic acid. went. Under reduced pressure, while raising the temperature of the reaction system from 310 ° C. to 340 ° C., aggregation was carried out for 5 hours to obtain an aromatic polyester having a solution viscosity of 8.7.
This polyester (A) was mixed with 98 parts by weight and 95 parts by weight of poly-4-methylpentene (TPX-M manufactured by Mitsui Petrochemical Co., Ltd.).
X-004) Add 2 parts by weight and 5 parts by weight of each, and add 30
After mixing for 15 minutes with a Henschel mixer maintained at ℃, extruded pellets were obtained while kneading in an extruder. Pellets obtained from the aromatic polyester alone were designated as A and poly-
The compound containing 2 parts by weight of 4-methylpentene is referred to as (I), and the compound containing 5 parts by weight thereof is referred to as (II).

The extrusion was performed under reduced pressure at a vent, a screw rotation speed of 100 rpm, and a cylinder temperature of 310 ° C. The pellets obtained were molded at a cylinder temperature of 315 ° C. The mechanical properties of the molded product are shown in Table-1.

As is apparent from Table-1, poly-4-methylpentene 2
Although there was almost no change in the mechanical properties with the addition of wt%,
As for the Izod impact value (with notch), as for the impact resistance value, the notched Izod of TPX (MX-004) is 4, while the notched Izod of aromatic polyester before blending is 45. The notched Izod of the blend composition obtained by the method of the invention was 51, which was higher than the Izod impact value of the original respective polymer.

The melt viscosity of the aromatic polyester / poly-4-methylpentene (2% by weight) molded product obtained above was measured using a Capirograph (manufactured by Toyo Seiki Co., Ltd.) (temperature: 330 ° C., shear rate: 10-). 10 ⁴ / sec). Similarly, the melt viscosity of the aromatic polyester alone and the aromatic polyester / poly-4-methylpentene (5% by weight) mixture were measured. The results are shown in Fig. 1. In the figure, (1)
Shows an aromatic polyester alone, (2) a poly-4-methylpentene 2 wt% blend, and (3) a 5 wt% blend. As is clear from Figure 1, for example, share rate
In the case of 10 ³ / sec, the aromatic polyester alone showed a melt viscosity of 750 poise, but when 2 wt% and 5 wt% of poly-4-methylpentene was added to this, the viscosity became 580 poise and 510 poise, respectively. Fell.

On the other hand, each of the above-mentioned three kinds of polymers was subjected to a resin temperature of 315 by using an injection molding machine having a semicircular spiral having a diameter of 5 mm.
° C., mold temperature 70 ° C., flow length of the injection pressure 800 kg / m ² in the injected where the aromatic polyester alone 786mm is a poly-4-methylpentene-2 wt% blend with 950mm and the same 5 wt% blend 1100mm Showed.

Examples 3 and 4 In the same manner as in Examples 1 and 2, except that TPX-MX-004 was replaced by poly-4-methylpentene (RT-18) manufactured by Mitsui Petrochemical Co., Ltd., aromatic polyester / Poly-
A 4-methylpentene formulation was obtained. The mechanical properties were measured using a 2 wt% formulation of RT-18 as (III) and a 5 wt% formulation of (RT) as well. The results are shown in Table-2. The melt viscosity was measured at 330 ° C. and a shear rate of 10 ³ / sec.

Examples 5 to 9 Aromatic polyesters A to E were prepared in the same manner as in Example 1 except that the formulation shown in Table 3 was used. Solution viscosity of the obtained polyester (in pentafluorophenol
The viscosity at 60 ° C. of the 0.1 wt% dissolved solution is measured by Ubbelohde viscometer) and the melting point is shown in Table-3.

This aromatic polyester was blended with polyolefin in the same manner as in Example 1 according to the formulation shown in Table 4, and its mechanical properties were measured. The results are shown in Table-4.

Example 10 High density polyethylene a (melt viscosity at 250 ° C .: 1300 po
ise) and aromatic polyester A were mixed and melted, and the melt viscosity was measured in the same manner as in Example 1 (measurement temperature: 3
30 ° C). The relationship between the a / A weight ratio and the melt viscosity is shown in FIG.

Example 11 Poly-4-methyl-pentene-1 (Mitsui Petrochemical Co., Ltd.)
Manufactured by TPX-1004: melt viscosity at 300 ℃: approx. 450 poise)
And aromatic-polyester A were mixed and melted, and the melt viscosity was measured by the same method as in Example 1 (measurement temperature: 330
C). The relationship between the compounding ratio and the solution viscosity is shown in FIG.

EFFECTS OF THE INVENTION The polymer composition of the present invention has a low melt viscosity and substantially improved flow characteristics upon melting without substantially impairing the mechanical properties of the aromatic polyester. Therefore, it becomes possible to easily obtain a molded product such as a thin sheet which has been extremely difficult with the conventional aromatic polyester.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between the shear rate and the melt viscosity of the polymer compositions obtained in Examples 1 and 2, and FIGS. 2 and 3 are the results obtained in Examples 10 and 11, respectively. It is a figure which shows the relationship between the aromatic polyester / polyolefin compounding ratio of a molecular composition, and melt viscosity. (1) is the aromatic polyester (2) is the aromatic polyester / poly-4-methylpentene (2% by weight), (3) is the aromatic polyester / poly-4-methylpentene (5% by weight) melt viscosity Show.

Claims (3)

[Claims] 1. Aromatic polyester 70 for all polymer components
9-9 wt% and 30-0.1 wt% polyolefin, a paraoxybenzoic acid [I], wherein the aromatic polyester may have a substituent.
A random copolymer of 2-hydroxynaphthoic acids [II], which may have a substituent, aromatic diol [III] and aromatic dicarboxylic acids [IV], wherein the polyolefin is ethylene, propylene, butene or 4-methylpentene. A polymer composition which is a homo- or copolymer of an olefin selected from the group consisting of: 2. An aromatic polyester containing [I] and [II] in an amount of 5 to 9 of the total amount of [I], [II], [III] and [IV].
5 mol%, [II] 5-20 mol% of the above total amount and [I]
The polymer composition according to item 1, which is obtained from a monomer composition containing equimolar amounts of [II] and [IV]. 3. The polyolefin is ethylene, propylene,
The polymer composition according to claim 1, which is at least one polyolefin selected from homopolymers of butene and 4-methylpentene.