KR920006212B1 - Poly ether ester block copolymer and its preparing method - Google Patents

Abstract

The polyester block copolymer having a good melting strength is produced by the addition of 0.05-1.0 mol% polyfunctional compound w.r.t. acid or low grade alkylester component of the copolymer. The polyfunctional compound is pref. triisocyanate compound, or contains isocyanate groups, hydroxyl group,carboxyl group, primary or secondary amine group and/or anhydride group. The copolymer is composed of dicarboxylic acid (e.g terephthalic acid, isophthaic acid, adipic acid, etc), their alkylester compounds and glycol compound (e.g ethylene glycol, 1,2-propanediol, etc) as a hard segment, and dicarboxyl compounds and poly(alkyleneoxide)glycol as a soft segment.

Description

Polyether Ester Block Copolymer and Other Manufacturing Methods

The present invention relates to novel polyether block copolymers and other methods of manufacturing, and more particularly to a polyether ester block copolymer having a good melt strength and a method for producing the same.

Conventional polyether ester block copolymers have been widely applied in the industrial sector because of their excellent impact resistance and processability, and in recent years, the demand is expanded in the fields of various industrial and household products, automobile parts, etc., in addition to thermoplastic polyurethanes. It is a highly functional material.

Such polyether ester block copolymers generally have a glycol component having 2 to 8 carbon atoms, a dicarboxylic acid or other ester-forming component mainly containing terephthalic acid, a polyether glycol component having a molecular weight of about 300 to 4,000, or the like. The polyether ester block copolymer having such a composition has been applied to various applications such as various injection molded articles, sheets, films, and highly stretchable fibers, and nowadays, excellent heat resistance is required to expand the use thereof. It has been applied to more extreme extrusion, blow molding, etc., and thus a high quality with a higher melt viscosity and better melt strength is required.

However, the polyether ester block copolymer prepared by the prior art is not limited in use due to poor thermal stability at high temperatures of 100 ° C. or higher, and also has low melt viscosity and low melt strength in low hardness products having high content of soft segments. Therefore, under extreme working conditions, workability is poor, and mechanical properties such as elastic recovery, creep characteristics, and fatigue resistance are poor due to high probability of hard segment breakage due to external force.

In addition, in US Patent No. 4,013,624, 0.3 to 1.2 molar equivalent% of the polyfunctional component consisting of only a hydroxyl group and a carboxyl group was added to the dicarboxylic acid as a crosslinking agent. As a result, the condensation reaction time and flowability were reduced. On the other hand, in the case of the linear polymer, it is known that the intrinsic viscosity increases and the end group content decreases with the increase of the degree of polymerization under the same polymerization conditions. However, as in the above technique, only the carboxyl group and the hydroxyl group are used. In the case where side chains or crosslinks are formed in the main chain of the polymer using a crosslinking agent, the end group content is increased according to the amount of the crosslinking agent rather than the degree of polymerization, so that the thermal stability is relatively low. Has been proven.

Accordingly, an object of the present invention is trifunctional to induce chemical crosslinking in the molecular structure during polymerization so that the polyether ester copolymer prepared according to the prior art can be melted even under extreme processing conditions such as extrusion or blow molding. The present invention provides a thermoplastic polyether ester block copolymer having improved thermal stability, melt strength, and melt viscosity by injecting a compound having at least one polyfunctional group, and a method for producing the same.

Hereinafter, the present invention will be described in detail.

The present invention relates to a polyetherester block copolymer, wherein all of the triisocyanate compounds or one or more isocyanate groups, and other hydroxyl groups, carboxyl groups, primary or secondary amine groups, and anhydrous acid groups all have at least trifunctionality. The polyfunctional ester block copolymer is characterized in that the polyfunctional compound is added in an amount of 0.05 to 1.0 mol% based on the acid component or other lower alkyl ester forming component in the polyether ester block copolymer.

Hereinafter, the present invention will be described in more detail.

The polyether ester block copolymer according to the present invention is firstly a poly (alkylene oxide) glycol component and a triisocyanate compound or one or more isocyanate groups in the polymerization component, and other hydroxyl groups, carboxyl groups, primary or secondary After reacting a polyfunctional compound having at least trifunctionality including both an amine group and an anhydride group for 10 to 20 minutes at a temperature of 100 to 130 ° C., a dicarboxylic acid or other lower alkyl ester-forming component and a glycol component And other reaction aids for esterification or transesterification, followed by condensation reaction under vacuum.

The polyetherester block copolymer in the present invention may also be referred to as a polyester elastomer, which is a soft segment such as a rubber chain and soft segments exhibiting entropy deformation with respect to stress, and general crystalline plastics. It is composed of two components of hard segment having crystallinity like chain of and having the same role as crosslinking point in rubber chain.

The hard segment includes ethylene glycol and dicarboxylic acid components such as terephthalic acid, isophthalic acid, old phthalic acid, adipic acid, suberic acid, azeraic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid or lower alkyl ester products thereof. And a glycol component such as 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexane dimethanol, The soft segment comprises a dicarboxylic acid component constituting the hard segment and a poly (alkylene oxido) glycol such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol having a molecular weight of about 400 to 4,000.

In this case, the physical properties of the final polymer are greatly affected by the poly (alkylene oxide) glycol component used. In particular, polyethylene glycol is relatively hydrophilic in comparison with polypropylene glycol or polyterramethylene glycol, and thus has low water resistance but oil resistance. In terms of advantages, polypropylene glycol and polytetramethylene glycol are hydrophobic, and thus have excellent water resistance and hydrolysis resistance.

On the other hand, the content of the hard segment may be up to 15 to 95% by weight based on the polyether ester block copolymer.

In the polyether ester block copolymer, the polyether component is amorphous and has a long chain length, and is a component that exhibits elasticity. The polyester component is crystalline and has a short chain length and is hardly broken when subjected to heat. When the heat is removed, it is a component having excellent thermoplasticity again showing crystallinity. According to the composition ratio of the soft segment and the hard segment, the copolymer has a rubbery and plastic intermediate property, but the content of the hard segment decreases relatively as the content of the soft segment increases. However, when the tensile force is applied in the final product form, the soft segment exhibits the same entropy deformation as rubber, but since the hard segment is subjected to stress concentration, in the case of an intrinsic soft product having a low content of hard segment, the hard segment breaks under strong tensile force. In addition to poor mechanical strength such as tensile strength and creep resistance, heat resistance, durability, and thermal stability during processing tend to be lowered.

Therefore, according to the present invention, in order to solve the above problems, addition of a polyfunctional acrylic compound having three or more functional groups capable of reacting with ester-forming functional groups during esterification, transesterification and polycondensation reactions By using this, a small amount of chemical crosslinking can be induced in the polyether ester block copolymer to improve not only the thermal stability of the final polymer but also its melt viscosity and melt strength.

In the present invention, as the polyfunctional compound, a triisocyanate compound or a polyfunctional compound having at least trifunctional all including at least one isocyanate group and other hydroxyl group, carboxyl group, primary or secondary amine group and anhydrous acid group is used. In this case, as the triisocyanate compound among the polyfunctional compounds that can be used, 1,1,1-tris [methylene (3-isocyanate-4-methylphenylcarbamate)] propane or 4,4 ', 4 "-triphenylmethane Triisocyanate and the like.

The polyfunctional compound as described above capable of inducing chemical crosslinking in the polyetherester copolymer may be added in an amount of 0.05 to 1.0 mol% based on the acid component or other lower alkylester forming component in the polyetherester block copolymer. The polymer can be prepared with improved melt strength as well as thermal stability. At this time, if the polyfunctional compound is added at 0.05 mol% or less, desired thermal stability and melt strength cannot be obtained. On the other hand, when more than 1.0 mol is used, the density of chemical crosslinks in the polymer is increased, resulting in poor workability. It is not preferable because it will fall out and also cause a decrease in mechanical properties.

On the other hand, the polymerization of the polyether ester block copolymer according to the present invention may be prepared using a conventional method of reacting by simultaneously adding a polymerization component, a catalyst, and a reaction aid including the multifunctional compound, but the present invention as follows. The production method according to the present invention can produce a polyether ester block copolymer having better performance as an elastic body.

That is, when polyfunctional compounds such as the triisocyanate compound and the like are added and used in the preparation of the polyether ester block copolymer, in order to protect the crystallinity of the hard segment, chemical crosslinking should be induced only to the soft segment. To this end, first, a poly (alkylene oxide) glycol component and a triisocyanate compound of the polymerization component are added and reacted with stirring at a temperature of 100 to 130 ° C. for 10 to 30 minutes, preferably 20 minutes. The catalyst and other reaction aids were added and refluxed to completely drain out low molecular weight by-products such as methanol and water.

After carrying out the esterification or transesterification reaction in this manner, the temperature in the reaction tube is heated to 250 to 280 DEG C while reducing the pressure in the tube to about 0.5 mmHg or less for about 60 minutes, and the reaction is stopped at a suitable agitator load. It discharged and obtained the target polyether ester copolymer.

In this case, as the polymerization catalyst, tetraalkyl titanate may be used alone or mixed with magnesium or calcium acetate. In addition, Mg [HTi (OR) ₆ ] ₂ produced from an alkoxide compound of an alkali earth metal and an ester compound of titanate may be used. Inorganic titanate compounds such as titanate complexes and titanium titanates, mixtures of calcium acetate and antimony trioxide, lithium or magnesium acetate, organotin compounds, or mixtures of organotin compounds and organotitanium compounds are also polymerization catalysts. Excellent performance.

In general, random block copolymers composed of polyether units and polyester units are deformed under stresses such as tensile and extrusion forces because polyester units having a high degree of crystallinity play a role of freezing phase, and then revert back to their initial form when external forces are removed. If the crystal part is subjected to a large external force that is broken, it is subjected to permanent deformation as much as the crystal region is deformed.

However, according to the present invention, a small amount of chemical crosslinking that does not invade thermoplastic in addition to physical crosslinking such as the crystallization zone disperses the concentrated stress received by the crystallization zone, thereby increasing the external force limit at which the crystallization can be destroyed. It will improve the mechanical strength of the ether ester block copolymer.

In addition, the polyether ester copolymer has lower melt viscosity and melt strength than the polyester homopolymer due to the extremely low crystallinity and high flowability of the polyether component. However, as in the present invention, when a small amount of chemical crosslinking is induced within a range that does not reduce the excellent thermoplasticity of the polyether ester block copolymer, the melt viscosity and the melt strength may be improved due to the increase in the entanglement of the polymer chain during melting. There is an advantage to this.

Hereinafter, the present invention will be described in more detail with reference to Examples. The catalysts and other additives used in Examples were prepared and used as slurry according to the following method.

[Catalyst]: 90% by weight of 1,4-butanediol and 10% by weight of tetrabutyl titanate were mixed and stirred at a temperature of 50 ° C. for 3 hours to prepare a catalyst slurry.

[Additive]: 20 g of 3,7-dioctylphenothiazine, 40 g of dilaurylthio dipropionate, and 24 g of 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane To prepare a slurry by mixing with 1,4-butanediol to 1kg.

Meanwhile, the abbreviations used in the following examples are as follows:

DMT: Dimethyl Terephthalate

BD: 1,4-butanediol

PTGB: Poly (terramethylene oxide) glycol (average molecular weight 1,000)

CAT: Catalyst Slurry

ADD: Additive Sli

MFC: Multifunctional Ingredient

IV: Intrinsic Viscosity

MP: crystal melting point

MV: Melt viscosity (measured at 235 ° C)

TMPI: 1,1,1-tris [methylene (3-isocyanate-4-methylphenylcarbamate)] propane

TPMI: 4,4 ', 4 "-triphenylmethanetriisocyanate

Example 1

PTGB and TMPI were first introduced into the polyester reaction tube of in-phase stainless steel with the composition shown in the following Table 1, and the reaction tube was heated to 120 ° C. over 40 minutes from room temperature and reacted with stirring for 20 minutes. , DMT, BD, CAT, ADD was added, and in 80 minutes, methanol was completely discharged while raising the temperature to 200 ° C.

After completely distilling off methanol, the pressure in the tube was reduced to 0.5 mmHg in 30 minutes, the temperature was raised to 255 ° C, and reacted for 45 minutes. To obtain the desired polyether ester copolymer.

The resin thus prepared was measured for physical properties by the following method and the results are shown in Table 1 and Table 2.

1. Intrinsic Viscosity: The polymer is dissolved in orthochlorophenol at a temperature of 30 ° C and the intrinsic viscosity (dl / g) is measured using a capillary viscometer.

2. Crystal melting point: Measured using differential calorimetry (℃).

3. Melt Viscosity: Measured using rheometer of RDS-7700 model manufactured by Leometrics.

4. Tensile strength: Measured according to ASTM D-412 (kg / ㎠).

5. Elongation at break: measured according to ASTM D-412 (%).

6. Resilience modulus: measured according to ASTM D-1054 (%).

Example 2

As shown in Table 1, except that 15.12 g of TMPI was added, the same procedure as in Example 1 was carried out, and the results are shown in Table 1.

Comparative Example 1

As shown in Table 1 below, the results were shown in Table 1, except that MFC was not used.

Table 1

Comparative Example 2

Except for reducing the content of TMPI from 0.34g to 27.03g was carried out in the same manner as in Example 1, and the results of measuring the main properties are shown in Table 2 below.

Comparative Example 3

Except for greatly increasing the content of TMPI from 27.03g to 118.23g was carried out in the same manner as in Example 1, and the results of measuring the main properties are shown in Table 2 below.

[Comparative Example 4]

The same composition as in Example 1 was performed, but all the components were initially added without first reacting TMPI and PTGB, and the methane was completely removed while raising the temperature in the reaction tube to 200 ° C. in 1 hour 45 minutes. Outflow. The following processes were performed similarly to Example 1, and the result of having measured the main physical property is shown in following Table 2.

[Table 2]

Claims (4)

In the polyether ester block copolymer, a polyisocyanate compound or a polyfunctional compound having at least trifunctionality, including at least one isocyanate group and other hydroxyl groups, carboxyl groups, primary or secondary amine groups and anhydrous acid groups, A polyetherester block copolymer, characterized by containing 0.05 to 1.0 mol 96% of the acid component or other lower alkyl ester-forming component in the polyether ester block copolymer. 2. The triisocyanate compound according to claim 1, wherein 1,1,1-tris [methylene (3-isocyanate-4-methylcarbamate)] propane or 4,4 ', 4 "-triphenylmethane triisocyanate is used as said triisocyanate compound. Polyether ester block copolymer, characterized in that. In preparing a polyetherester block copolymer by adding a catalyst, a thermal stabilizer and other reaction aids to the polymerization component, and esterification or transesterification, and polycondensation reaction under vacuum, first, poly (alkylene oxide) in the polymerization component A polyfunctional compound having a trifunctional or more than trifunctional compound, including a glycol component and a triisocyanate compound or one or more isocyanate groups and other hydroxyl groups, carboxyl groups, primary or secondary amine groups and anhydrous acid groups at 100 to 130 ° C After the reaction for 10 to 20 minutes at a temperature, a polyether ester block air, characterized in that the esterification or transesterification reaction by adding a dicarboxylic acid or other lower alkyl ester-forming component and a glycol component and other reaction aids Process for the preparation of coalescing. 4. The triisocyanate compound of claim 3, wherein 1,1,1-tris [methylene (3-isocyanate-4-methylphenyl carbamate)] propane or 4,4 ', 4 "-triphenylmethane triisocyanate is used. Method for producing a polyether ester block copolymer, characterized in that the use.