JPH0615657B2 - Block poly-ether ester copolymer composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a block polyether ester copolymer composition having excellent mechanical properties and weather resistance.

<Prior Art> A block polyether ester copolymer having polybutylene terephthalate as a main hard segment and poly (tetramethylene oxide) glycol as a soft segment has flexibility, elastic properties, mechanical strength, and oil / chemical resistance. Since it is thermoplastic with excellent properties such as heat resistance, it is used in the fields of rubber and flexible plastics, taking advantage of the fact that it can be molded by the same processing technique as thermoplastics.

However, this block polyether ester copolymer is extremely susceptible to photodegradation, and when it is used in applications where it is exposed to the outdoors, for example, its mechanical strength decreases in a relatively short time and it becomes unusable. However, there is a problem that cracks are generated on the surface of the molded product, and the product is colored to deteriorate the appearance, thus lowering the commercial value.

Conventionally, in order to improve the weather resistance of a block polyether ester copolymer, a method of adding a weather resistant agent has been proposed. In particular, JP-B-52-22744 describes a method of adding a hindered phenol compound and a hindered amine compound in order to improve the heat resistance and weather resistance of the block polyether ester copolymer.

On the other hand, it is possible to add titanium dioxide to a block polyether ester copolymer to improve wear resistance.
No. 11022.

<Problems to be Solved by the Invention> By adding only a hindered amine compound to the block polyether ester copolymer as described in JP-B-52-22744, the weather resistance of the block polyether ester copolymer is improved. The method of improving the properties is insufficient in the improvement effect and cannot be used as a vehicle exterior material.

Further, when only titanium dioxide is added to the block polyether ester copolymer, some effect can be seen in improving the weather resistance of the block polyether ester copolymer, but this is not a satisfactory situation.

Therefore, it is an object of the present invention to provide a block polyetherester copolymer composition which has a significantly improved weather resistance and can be used as an automobile exterior material and has excellent mechanical properties.

<Means for Solving Problems> The inventors of the present invention have made earnest studies to significantly improve the weather resistance of the block polyether ester copolymer. As a result, titanium dioxide and a hindered amine compound were added to the block polyether ester copolymer. The inventors have found that the weather resistance of the block polyether ester is significantly improved and that the block polyether ester has excellent mechanical properties when they are added together, and the present invention has been accomplished.

That is, the present invention is based on 100 parts by weight of the block polyether ester copolymer;
The present invention provides a block polyether ester copolymer composition containing 0.01 part by weight and 0.01 to 5 parts by weight of a hindered amine light stabilizer.

The block polyether ester copolymer in the present invention means an acid component in which 60 mol% or more, preferably 80 mol% or more of the dicarboxylic acid component is an aromatic dicarboxylic acid or its ester-forming derivative, a low molecular weight glycol and a molecular weight. 300-6000, preferably 600-35
00 means a copolymer obtained by polycondensation reaction with poly (alkylene oxide) glycol.

Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, bis (p-carboxyphenyl) methane, 4,4'-diphenyldicarboxylic acid. , 4,4'-diphenyl ether dicarboxylic acid and the like known as raw materials for polyester.

Among these dicarboxylic acids, terephthalic acid and isophthalic acid are preferably used from the viewpoint of moldability of the resulting block polyether ester copolymer.

As the ester-forming derivative, a lower alkyl ester of the above acid, particularly a methyl ester is preferably used.

The acid components other than the above-mentioned acids used in an amount of 40 mol% or less include adipic acid, sebacic acid, azelaic acid,
Aliphatic dicarboxylic acids such as dodecanedioic acid and alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid and their ester-forming derivatives are mentioned.

The low molecular weight glycol is a glycol containing 70 mol% of 1,4-butanediol, preferably 80 mol% or more, and other glycols include ethylene glycol, 1,3-propanediol, 1, 5-
Pentanediol, 1,6-hexanediol, diethylene glycol and 1,4-cyclohexanediol,
1,4-cyclohexane dimethanol etc. are mentioned.

Examples of the poly (alkylene oxide) glycol include polyethylene glycol, poly (propylene oxide) glycol, poly (tetramethylene oxide) glycol, and the like, preferably a homopolymer of poly (tetramethylene oxide) glycol or the homopolymer thereof. A random copolymer or a block copolymer in which two or more kinds of constituent repeating units are copolymerized in a random or block form, or 2 of the above homopolymers or copolymers.
A mixed polymer in which one or more kinds are mixed is used.

The block polyether ester copolymer can be obtained by a known melt polycondensation reaction.

For example, a method in which an aromatic dicarboxylic acid is esterified with a low molecular weight glycol and poly (alkylene oxide) glycol, and the resulting ester compound is supplied to a polycondensation reaction tank to perform melt polycondensation, or the aromatic dicarboxylic acid is reduced A method is used in which esterification is carried out with a molecular weight glycol and then poly (alkylene oxide) glycol is added to the obtained ester compound to carry out melt polycondensation.

The content of poly (alkylene oxodito) glycol in the block polyether ester copolymer obtained by the polycondensation reaction is preferably in the range of 15 to 75% by weight, and when it is 15% by weight or less, the block polyether ester is contained. The elastic properties of the copolymer are not sufficient, and when it is 75% by weight or more, the moldability of the block polyether ester is poor, which is not preferable.

The relative viscosity of the block polyether ester copolymer used in the present invention is preferably in the range of 0.8 to 4.5. If it is less than 0.8, the mechanical properties are not sufficient, and if it is more than 4.5, the fluidity becomes poor, which is not preferable. In this case, the relative viscosity is a value measured in o-chlorophenol at a concentration of 0.5% by weight and a temperature of 25 ° C.

Titanium dioxide, which is a component of the weather resistance improver used in the present invention, is a rutile type or anatase type having a purity of 80% or more and an average particle size of 5 produced by a sulfuric acid method or a chlorine method.
Preference is given to titanium dioxide of μ or less. Titanium dioxide having an average particle diameter of 5 μm or more is not preferable because it tends to form coarse disperse foreign matter in the block polyether ester copolymer. Particularly, the preferable effect is obtained when rutile type titanium dioxide is used.

The titanium dioxide is added in an amount of 0.1 to 40 parts by weight, particularly preferably 0.2 to 20 parts by weight, based on 100 parts by weight of the block polyether ester. If the amount is less than 0.1 parts by weight, the problem cannot be solved. If it is 40 parts by weight or more, the original excellent mechanical properties of the block polyether ester copolymer are deteriorated.

The hindered amine light stabilizer which is another component of the weather resistance improver of the present invention is 4-benzoyloxy-2,2,2.
6,6-Toteramethylpiperidine, bis- (2,2,
6,6-Tetramethyl-4-piperidinyl) adipate, Bis- (2,2,6,6-tetramethyl-4-piperidinyl) suberate, Bis- (2,2,6,6-tetramethyl-4-piperidinyl) ) Sebacate, screw-
(2,2,6,6-tetramethyl-4-piperidinyl)
Phthalate, bis- (2,2,6,6-tetramethyl-
4-piperidinyl) isophthalate, bis- (2,2,
6,6-Tetramethyl-4-piperidinyl) terephthalate, bis- (1,2,2,6,6-pentamethyl-4)
-Piperidinyl) sebacate, N, N'-bis- (2,
2,6,6-Tetramethyl-4-piperidinyl) adipamide, bis- (1,2,2,6,6-pentamethyl-4)
-Piperidinyl) -n-butyl (3,5-ditertiarybutyl-4-hydroxybenzyl) malonate, bis- (1,
2,2,6,6-Pentamethyl-4-piperidinylbenzyl) malonate, bis- (1,2,2,6,6-pentamethyl-4-piperidinyl) diethyl malonate, bis- (2,2,6 , 6-Tetramethyl-4-piperidinyl) dibenzylmalonate, bis- (2,2,6,6-
Tetramethyl-4-piperidinyl) benzylethyl malonate, bis- (2,2,6,6-tetramethyl-4-
Piperidinyl) -n-butyl (3,5-ditertiary butyl-
4-hydroxybenzyl) malonate, butanetetracarboxylic acid tetra- (2,2,6,6-tetramethyl-
4-piperidinyl) ester, 1- [2- [3- (3,
5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy]
-2,2,6,6-tetramethylpiperidine, poly [[6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diyl]
[(2,2,6,6-tetramethyl-4-piperidinyl) imino]] compound having a molecular weight of 2000 or more, dimethyl-1- (2-hydroxyethyl) -4-dimethyl succinate
A hydroxy-2,2,6,6-tetramethylpiperidine compound having a molecular weight of 2000 or more is mentioned as an example, and is a hindered amine light stabilizer having one or more structures represented by the following formula (I) in the compound. is there.

In the formula, R1, R2, R3, and R4 are alkyl groups having 1 to 6 carbon atoms, and may be different or the same.

The amount of the hindered amine light stabilizer compounded is 0.0 based on 100 parts by weight of the block polyether ester copolymer.
1 to 5 parts by weight, particularly 0.02 to 4 parts by weight are preferably used. If it is less than 0.01 parts by weight, the problems of the present invention cannot be solved. If it is 5 parts by weight or more, the excellent mechanical properties inherent to the block polyether ester copolymer will be impaired.

Furthermore, when the compounding amount of the hindered amine light stabilizer is 1 part by weight or more, it is preferable to use the hindered amine light stabilizer having a molecular weight of 1,000 or more. A hindered amine-based light stabilizer having a molecular weight of less than 1000 may bleed out on the surface of the molded product and reduce the value of the molded product.

The manufacturing method of the present invention is not particularly limited. Using a single-screw or twin-screw extruder, roll, Banbury mixer, etc., to blend titanium dioxide and a hindered amine light stabilizer into the molten block polyether ester copolymer, or during the block polyether ester copolymer polymerization process. A method of adding titanium dioxide and a hindered amine light stabilizer is used, but a method of melt-kneading the block polyether ester copolymer, titanium dioxide and the hindered amine light stabilizer is preferably used.

Various additives can be added to the composition of the present invention within a range that does not impair the object of the present invention. For example, molding aids such as known crystal nucleating agents and lubricants, known antioxidants, ultraviolet absorbers, hydrolysis resistance improvers, colorants such as pigments and dyes,
An antistatic agent, a conductive agent, a flame retardant, a reinforcing agent, a filler, an adhesive, a plasticizer, a release agent and the like can be optionally contained.

<Examples> The effects of the present invention will be described below with reference to Examples. All percentages and parts in the examples are by weight. The relative viscosity is a value obtained by measuring a 0.5% polymer solution using o-chlorophenol as a solvent at 25 ° C. The melting point is also a melting peak temperature measured by a differential scanning calorimeter (DSC-1B type manufactured by Perkin Elmer) unless otherwise specified.

Reference example 2390 parts of dimethyl terephthalate, number average molecular weight 14
00 poly (tetramethylene oxide) glycol 14
Charge 60 parts and 1,64-butanediol 1664 parts together with titanium tetrabutoxide catalyst 0.05% (against polymer) into a reaction vessel equipped with a helical ribbon type stirring blade.
After heating at 10 ° C. for 2 hours, 95% of the theoretical amount of methanol was distilled out of the system. Then raise the temperature to 245 ° C,
The pressure in the system is reduced to 0.2 mmHg over 50 minutes,
Polymerization was performed for 2 hours under the conditions. The block polyether ester copolymer obtained had a melting point of 207 ° C. and a relative viscosity of 2.01.

The polymer obtained by this melt polymerization is discharged into water as a gut having a diameter of about 3 mm and is cut through a take-up machine.
Pelletized (Polymer A).

Examples 1-8, Comparative Examples 1-3 Polymer A with rutile titanium dioxide (manufactured by Ishihara Sangyo Co., Ltd.)
R-820) and the hindered amine light stabilizer shown in Table 1 were dry-blended, and then melt-kneaded at 240 ° C. with a twin-screw 45 mmφ extruder to form pellets. The obtained pellets and polymer A were vacuum dried at a temperature of 80 ° C. for 5 hours and then press-molded at a temperature of 240 ° C. into a sheet having a thickness of 1 mm. This molded sheet was punched into a No. 3 dumbbell test piece described in JIS K-6301.

The weather resistance was examined by irradiating the test piece with light in a sunshine weatherometer. The sunshine weatherometer black panel temperature was 63 ° C and was sprayed with water for 18 minutes every 2 hours. When the breaking elongation retention rate becomes 50%,
The weather resistance was evaluated by measuring the crack initiation time on the irradiated surface. The breaking elongation was measured according to JIS K-6301 method. The measurement results are shown in Table 2. For comparison, Table 2 also shows the measurement results of the sample without addition, the sample added with each of titanium dioxide and the hindered amine light stabilizer alone.

It is clear from Table 2 that the composition of the present invention exhibits excellent weather resistance.

<Effects of the Invention> The composition obtained by adding titanium dioxide and a hindered amine light stabilizer to the block polyether ester copolymer in combination has excellent weather resistance and excellent mechanical properties inherent to the block polyether ester copolymer. It is expected that the conventional block polyether ester copolymer could not be used, but it is expected to be expanded to applications exposed to the outdoors such as automobile exterior parts.

Claims (1)

[Claims] 1. A block polyether ester copolymer 1
A block polyether ester copolymer composition comprising 0.1 to 40 parts by weight of titanium dioxide and 0.01 to 5 parts by weight of a hindered amine light stabilizer, relative to 00 parts by weight.