JPH0491123A - Polyester - Google Patents

Abstract

PURPOSE:To obtain the title polyester consisting of each specific acid component and glycol component in the recurring units, having excellent flexibility, transparency, heat resistance and moldability and capable of readily forming film, etc. CONSTITUTION:The aimed polyester composed of an aromatic dicarboxylic acid residue and residue consisting of long chain aliphatic dicarboxylic acid having >=140 molecular weight used as acid components and ethylene glycol residue and 1,4-butanediol residue used as glycol components in recurring units constituting polyester and capable of satisfying the equations 50mol%<=A<=95mol%, 5mol%<=B<=50mol%, 35mol%<=C<=60mol% and 40mol%<=D<=65mol% (wherein A is component ratio of aromatic dicarboxylic acid residue; B is component ratio of long chain aliphatic dicarboxylic acid residue having >=140 molecular weight; C is component ratio of ethylene glycol residue; D is component ratio of 1,4-butanediol residue).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to polyesters capable of forming flexible moldings. Specifically, the present invention relates to a polyester that can easily form flexible molded products with excellent transparency, elastic recovery, heat resistance, and moldability.

[Prior Art] Polyesters, particularly polyethylene terephthalate, polybutylene terephthalate, poly-1,4-cyclohexane dimethylene terephthalate, and polyesters based on these, have excellent physical and chemical properties, and can be used as fibers, Widely used as films and molded products.

However, all of them lack flexibility and elastic recovery at room temperature, which limits their ability to expand their use. In order to improve these drawbacks, a method of copolymerizing a soft segment with polyester has been considered. For example, Tokuko Sho 57-485
No. 77 discloses a copolymer of polybutylene terephthalate with a long chain polyether such as polytetramethylene glycol, and Japanese Patent Publication No. 1987-8709 discloses a copolymer of polyethylene terephthalate with a long chain aliphatic dicarboxylic acid such as trimerized fatty acid. Polymerized product, and further
The publication discloses a product in which polybutylene terephthalate is copolymerized with trimerized fatty acid.

[Problems to be solved by the invention] However, polybutylene terephthalate copolymerized with long-chain polyether has poor weather resistance, heat resistance, and transparency; Polymerized products have a slow crystallization rate and are difficult to form into fibers, films, sheets, and other molded products. Polybutylene terephthalate copolymerized with trimerized fatty acids has high crystallinity and is flexible. There were disadvantages such as inferiority.

An object of the present invention is to solve the above-mentioned conventional drawbacks, and to provide a polyester that can easily form flexible molded products with excellent transparency, elastic recovery, heat resistance, and moldability. be.

[Means for Solving the Problems] The object of the present invention described above is to provide a method in which, in repeating units constituting a polyester, a residue consisting of an aromatic dicarboxylic acid residue and a long-chain aliphatic dicarboxylic acid having a molecular weight of 140 or more is used as an acid component. This can be achieved by a polyester characterized in that it is composed of ethylene glycol residues and 1,4-butanediol residues as glycol components, and the component ratio of each component is represented by the following formula.

50 mol%≦A≦95 mol% 5 mol%≦B≦50 mol% 35 mol%≦C≦60 mol% 40 mol%≦D≦65 mol% (However, A is the component ratio of aromatic dicarboxylic acid residues , B is the component ratio of residues consisting of long-chain aliphatic dicarboxylic acids with a molecular weight of 140 or more, C is the component ratio of ethylene glycol residues, D
is the component ratio of 1,4-butanediol residue. ) In the present invention, polyester refers to a hard segment whose main constituent is an aromatic dicarboxylic acid residue as an acid component, a soft segment whose main constituent is a residue of a long-chain aliphatic dicarboxylic acid with a molecular weight of 140 or more, It is composed of ethylene glycol residues and 1,4-butanediol residues as glycol components.

In the present invention, the aromatic dicarboxylic acid residues constituting the hard segment are formed from aromatic dicarboxylic acids and ester-forming derivatives thereof. Specifically, the following can be mentioned.

(X in the formula is 10-, -5O-1-SO2-C (CII
3>2--CO-1n is O or 1.

Further, the hydrogen atom bonded to the aromatic ring may be substituted with a halogen group. ) In the present invention, the acid components constituting the aromatic dicarboxylic acid residue include the following.

(In the formula, R1-R6 are hydrogen atoms or alkyl groups, X is 10-, -5O-1-SO2-C(CL)2-
CO-1n is 0 or 1.

Further, the hydrogen atom bonded to the aromatic ring may be substituted with a halogen group. ) Specifically, terephthalic acid, isophthalic acid, phthalic acid,
Examples include naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenyl ether dicarboxylic acid, benzophenone dicarboxylic acid, and ester-forming derivatives thereof, among which terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid,
and ester-forming derivatives thereof are preferred. Further, these aromatic dicarboxylic acid components may be used alone or in combination of two or more.

In the present invention, the amount of aromatic dicarboxylic acid residue is preferably 50 to 95 mol% of the acid component, more preferably 55 to 95 mol%.
93 mol%, more preferably 60 to 90 mol%
It is. If the amount of aromatic dicarboxylic acid residues is less than 50 mol %, the heat resistance of the polyester will decrease, and the mechanical properties of the molded product obtained from it will also decrease, which is not preferable. On the other hand, if it exceeds 95 mol%, the flexibility of the molded product obtained from the polyester decreases, which is not preferable.

In the present invention, the long-chain aliphatic dicarboxylic acid residue constituting the soft segment is formed from a long-chain aliphatic dicarboxylic acid and its ester-forming derivative. Specifically, the following can be mentioned.

-ooc-y-coo- [In the formula, Y is an alkylene group represented by (CH2), , l (m is an integer of 4 to 5o), or 1 to 2 hydrogen atoms of the alkylene group are phenyl group or a group substituted with an alkyl group. ] The molecular weight of the long-chain aliphatic dicarboxylic acid that can be used in the present invention is preferably 140 or more,
More preferably 180 or more, still more preferably 2
00 or more. If the molecular weight is less than 140, the heat resistance of the polyester will decrease, and the flexibility and elastic recovery properties of molded products obtained from the polyester will decrease, which is not preferable.

In the present invention, the acid components constituting the long-chain aliphatic dicarboxylic acid residues include the following.

R' OOC-Y -COOR8 [In the formula, R7 and R8 are hydrogen atoms or alkyl groups, and Y is (CH2). (m is an integer of 4 to 50) or a group in which 1 to 2 hydrogen atoms of the alkylene group are substituted with a phenyl group or an alkyl group. Specific examples include adipic acid, pimelic acid, superric acid, azelaic acid, sebacic acid, undecanedioic acid,
Dodecanedioic acid, brassylic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedionic acid, heptadecanedionic acid, octadecanedioic acid, nonadecanedionic acid, icosanedioic acid, tocosanedionic acid, etc., and one or more hydrogen atoms of these compounds are replaced with an alkyl group. , those substituted with phenyl groups, etc., dimer acids obtained by trimembering unsaturated fatty acids having 10 to 30 carbon atoms, hydrogenated products thereof, and ester-forming derivatives thereof. These long-chain aliphatic dicarboxylic acid components may be used alone or in combination of two or more.

In the present invention, the amount of long-chain aliphatic dicarboxylic acid residues is preferably 5 to 50 mol% of the acid component, more preferably 7 to 50 mol%.
45 mol%, more preferably 10 to 40 mol%
It is. The amount of long chain aliphatic dicarboxylic acid residues is 50 mol%
If it exceeds this amount, the heat resistance of the polyester will decrease, and the mechanical properties of the molded product obtained from it will also decrease, which is undesirable.

On the other hand, if the amount of long-chain aliphatic dicarboxylic acid residues is less than 5 mol %, the flexibility of the molded product obtained from the polyester decreases, which is not preferable.

In the present invention, the glycol component consists of ethylene glycol and 1,4-butanediol, and the amount of ethylene glycol residue is preferably 35 to 60 mol%, more preferably 36 to 58 mol%, and still more preferably 37 to 60 mol%.
It is 55 mol%. On the other hand, the amount of 1,4-butanediol residue is preferably 40 to 65 mol%, more preferably 40 to 65 mol%.
It is 2 to 64 mol%, more preferably 45 to 63 mol%. If the ethylene glycol residue content is less than 35 mol% or if the 1,4-butanediol residue content exceeds 65 mol%, the flexibility of the molded product obtained from the polyester will decrease, which is not preferable. On the other hand, if the ethylene glycol residue is more than 60 mol% or the 1,4-butanediol residue is less than 40 mol%, the crystallization rate of the polyester will be low and it will stick during molding, making it difficult to mold. The transparency of the molded product also decreases, which is not preferable.

As described above, the object of the present invention can only be achieved by using both ethylene glycol and 1,4-butanediol together within a specific range. When only ethylene glycol is used, the crystallization rate becomes low and molding becomes difficult, which is not preferable. On the other hand, when only 1°4-butanediol is used, the flexibility of the molded product obtained from the polyester decreases, which is not preferable.

The structure of the polyester of the present invention is preferably a linear polymer in which each segment represented by the following formula is arranged in blocks or randomly.

p[-QC-Ar-COOCI(2CH20-]Q
[-QC-Ar-COOCH2CI2 CH2CH20
-]r [-QC-Y-COO-CH2CH2O punishments
[-QC-Y-Coo-CL CH2CH2CH2
0-][However, Ar in the formula is an aromatic functional group represented by, and X is 10--5O-1
-3O2--C(C!13)2--CO-1n is 0 or 1, and the hydrogen atom bonded to the aromatic ring may be substituted with a halogen group. Also, Y is (CII
2) An alkylene group represented by l'n (m is an integer of 4 to 50), or one hydrogen atom of the alkylene group
~2 are groups substituted with phenyl groups or alkyl groups. Furthermore, plqS rSs is polyester 1
It is a coefficient representing the number of each segment in the molecule, and is 1
~50 integer. ] The sum of the coefficients in the above equation (p+q+r+s) is
Although not particularly limited, in order to achieve the object of the present invention, it is preferably 5 or more and 200 or less.

If this value is less than 5, the moldability will be poor and the
Exceeding this is not preferable because the mechanical properties deteriorate.

In the present invention, in addition to the above-mentioned components, other components may be copolymerized within a range that does not impair the purpose of the present invention. For example, as the acid component, 1.4 cyclohexanedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 5-sodium sulfoisophthalic acid, trimellitic acid, trimesic acid, etc., or their ester derivatives, p as a hydroxycarboxylic acid component
-oxybenzoic acid, p-hydroxymethylbenzoic acid, etc.
or their ester derivatives, etc., and as alcohol components, 1.6-hexanediol, 1,8-octanediol, 1.10-decanediol, 1.12-dodecanediol, neopentyl glycol, diethylene glycol, polyoxyalkylene glycol , 1,4-
Cyclohexanediol, 1,3-cyclohexanediol, 1,2-cyclohexanediol, 1,4-cyclohexane dimetatool, 1,3-cyclohexane dimetatool, 1,2-cyclohexane dimetatool, spiroglycol, or bisphenol A1 Examples include bisphenol S and their ethylene oxide adducts, trimethylolpropane, and the like.

The polyester of the present invention may be used as a crystal nucleating agent or as a crystal nucleating agent depending on its use.
Antioxidants, color inhibitors, pigments, dyes, ultraviolet absorbers,
A mold release agent, lubricant, flame retardant, antistatic agent, inorganic and/or organic particles, etc. can be blended.

In the present invention, the intrinsic viscosity of polyester is 0.2 to 3.
．． 0 is preferable, more preferably 0.3 to 2.0
and more preferably 0.4 to 1.5. Intrinsic viscosity is 0. If it is less than 2, the moldability will be poor, and if it exceeds 3.0, the mechanical properties will deteriorate, which is not preferable.

In the present invention, the glass transition point (Tg) of the polyester is preferably 20°C or lower, more preferably 15°C or lower, and even more preferably 10°C or lower. Tg is 20
If the temperature exceeds ℃, the flexibility decreases, which is not preferable.

In the present invention, the melting point (Tm) of polyester is 120
The temperature is preferably 150°C or higher, more preferably 150°C or higher, and still more preferably 170°C or higher. Tm is 120
If it is less than ℃, the heat resistance and mechanical properties will deteriorate, which is not preferable.

In the present invention, the crystallization rate (ΔTc) of the polyester is preferably 40°C or higher, more preferably 50°C or higher, and still more preferably 60°C or higher. ΔTc is 4
If it is less than 0°C, the crystallization rate of the polyester will be low and molding will be difficult, which is not preferable.

Although the method for producing polyester in the present invention is not particularly limited, for example, an aromatic dicarboxylic acid, a long-chain aliphatic dicarboxylic acid with a molecular weight of 140 or more or a lower alkyl ester thereof, and ethylene glycol and 1,4-butanediol. The most common method of production involves a first stage reaction in which a low polymer is produced by an esterification reaction or transesterification reaction, and a second stage reaction in which the low polymer is polycondensed. To explain the above method more specifically, dimethyl terephthalate, dimethyl dimerate, ethylene glycol, 1,4
Butanediol is charged into a polymerization reactor equipped with a stirrer, a nitrogen gas inlet tube, and a vacuum distillation device, and heated while stirring at a temperature of 150 to 250° C. while flowing nitrogen to cause a transesterification reaction. After that, the pressure is gradually reduced to 0.
A polycondensation reaction is carried out under a reduced pressure of 001 to 3 Torr and at a temperature of 200 to 300°C to obtain a polyester. During this reaction, titanium, lead, zinc, calcium, magnesium,
Transesterification catalysts such as manganese compounds, polycondensation catalysts such as antimony, germanium, titanium compounds, antioxidants, stabilizers such as phosphorus compounds, etc. can be used.

The polyester of the present invention can be used by being molded into fibers, films, and other molded products, and the molding method will be explained below using a film as an example.

After sufficiently drying, the obtained polyester is melt-extruded using an extruder, discharged from a sheet-like or cylindrical nozzle, and introduced into a cooling roll or a refrigerant such as water, where it is cooled and solidified. Here, when extruding into a sheet, a calendar casting method in which the film is cooled and solidified while being pressed between at least a pair of rolls is preferred because the obtained film has good transparency and mechanical properties.

In the present invention, the film haze of the film obtained from polyester is preferably 10% or less, more preferably 5% or less, and even more preferably 3% or less. If the film haze exceeds 10%, transparency deteriorates, which is not preferable.

In the present invention, the Young's modulus of the film obtained from polyester is preferably 1 to 30 kg/mm2, more preferably 2 to 25 kg/mm2, and even more preferably 3 to 20 kg/mm2. If the Young's modulus is less than 1 kg/mm 2 , it becomes difficult to maintain the shape, and if it exceeds 30 kg/mm 2 , the flexibility decreases, which is not preferable.

In the present invention, the elastic recovery rate of the film obtained from polyester is preferably 50% or more, more preferably 60% or more, and still more preferably 70% or more. If the elastic recovery rate is less than 50%, the mechanical properties will deteriorate, which is not preferable.

[Example] The present invention will be explained in more detail below using examples.

Note that the characteristics in the examples were measured as follows.

(1) Intrinsic viscosity of polyester Measurement was performed at 25°C using 0-chlorophenol as a solvent.

(2) Thermal properties of polyester 10 mg of polyester was placed in a sample pan and scanned from 10 to b using a differential scanning calorimeter to measure Tg, Tm, Tc, and Tc'. Note that ΔTc was determined by the following formula.

ΔTc=Tc −Tc TC: Crystallization temperature when the temperature is raised Tc': Crystallization temperature when the temperature is lowered (3) Composition analysis of polyester Polyester is hydrolyzed with an alkali, the acid component and the glycol component are isolated, and each component is was analyzed by gas chromatography or high performance liquid chromatography, and the composition ratio was determined from the peak area of each component.

(4) Film haze Regarding films obtained from polyester, JIS
The film haze was measured according to K, -6714, and was calculated in terms of 100 μm using the following formula.

H+oo (%') = HX100/dH: Actual value of Hayes measurement (%) d: Film thickness at Hayes measurement part (μm) (5) Young's modulus of the film obtained from polyester, ASTM
Young's modulus was measured according to D-882-81 (Method A).

(6) Elastic recovery rate Sample the film obtained from polyester to a width of 10 mm, attach it to a tensile tester so that the trial length is 50 mm, and set the tension tester at a tensile speed of 10 mm/min.
A tensile deformation of 0% was applied, the sample was immediately contracted at the same speed, and the sample length (L) when the bowing stress became 0 was measured and calculated using the following formula.

Elastic recovery rate = (75-L)/25x100 (%) Example 1 61 parts by weight of dimethyl terephthalate, 33 parts by weight of dimethyl dimerate having 36 carbon atoms, 20 parts by weight of ethylene glycol, 40 parts by weight of 1,4-butanediol, and Transesterification reaction, polycondensation reaction 0.1 part by weight of tetrabutyl titanate was added as a catalyst, and the transesterification reaction was carried out according to a conventional method.Then, the polycondensation reaction was carried out under high temperature and reduced pressure to obtain a copolymerized polyester with an intrinsic viscosity of 0.85. Obtained. The composition of the obtained polyester was 85 mol% of terephthalic acid residues, 15 mol% of dimer acid residues, and 40 mol% of ethylene glycol residues.
mol%, 1°4-butanediol residue was 60 mol%.

The infrared absorption spectrum of polyester measured by the thin film method was as shown in Figure 1. As is clear from FIG. 1, absorption due to C-0 stretching vibration based on ester bonds is observed at 1730 cnr', and absorption due to C-O stretching vibration is observed at 1270.1250.1170.1150 cm', indicating that polyester production is confirmed. Furthermore, absorption due to aliphatic C-H stretching vibration is 2940.2860
c+n-', and the presence of dimer acid was confirmed. The obtained polyester has a Tg of -4°C and a Tm of 180
°C and ΔTc were 150 °C, indicating a high melting point and high crystallinity. The obtained polyester was formed into a film according to a conventional method. Film formability was good, and a film with a thickness of 100 μm was obtained. The resulting film had a heis of 1.0%, a Young's modulus of 15 kg/mm2, an elastic recovery rate of 82%, and was transparent.
Both flexibility and elastic recovery were excellent.

Comparative Example 1 A copolymerized polyester was obtained in the same manner as in Example 1, except that 66 parts by weight of dimethyl terephthalate, 35 parts by weight of dimethyl dimerate having 36 carbon atoms, and 50 parts by weight of ethylene glycol were used.

The composition of the obtained polyester was 85 terephthalic acid residues.
mol %, dimer acid residue 15 mol %, and ethylene glycol residue 100 mol %.

The obtained polyester has a Tg of 20°C and a Tm of 220°C.
, ΔTc was 35° C., indicating low crystallinity.

The obtained polyester was formed into a film in the same manner as in Example 1, but it was difficult to form a film due to strong adhesion to the drum during film formation. In addition, the haze of the obtained film was 40.0%,
Young's modulus is 45kg/11112, elastic recovery rate is 40%
The transparency, flexibility, and elastic recovery properties were all poor.

Examples 2 to 5, Comparative Examples 2 to 5 As shown in Table 1, polyesters of various compositions and films thereof were produced in the same manner as in Example 1. The composition, intrinsic viscosity, glass transition point, melting point, crystallization rate, film stiffness, Young's modulus, and elastic recovery rate of each were as listed in Table 1.

Examples 2 to 5 are all within the objective range of the present invention, and the obtained polyesters have excellent heat resistance and crystallinity,
The moldability was good, and the obtained film had good transparency, flexibility, and elastic recovery.

On the other hand, Comparative Example 2 contained only a glycol component or 1°4-butanediol, which was outside the scope of the present invention, and the resulting polyester film had poor flexibility. In Comparative Example 3, the amount of 1,4-butanediol is larger than the range of the present invention, and the amount of ethylene glycol is smaller than the range of the present invention, and the obtained polyester film has a Young's modulus of was large and the flexibility was poor. Comparative Example 4 has a large content of dimer acid, which is a long-chain aliphatic dicarboxylic acid, which is outside the scope of the present invention, and the resulting polyester has a low melting point and crystallization rate.
It was difficult to form a film. Comparative Example 5 had a small content of dimer acid, which is a long-chain aliphatic dicarboxylic acid, which was outside the scope of the present invention, and the resulting polyester film had a large Young's modulus and poor flexibility.

(The following is a blank space) [Effects of the Invention] As described above, the polyester of the present invention contains aromatic dicarboxylic acid residues and long-chain aliphatic dicarboxylic acid residues as acid components, and ethylene glycol residues and 1 as glycol components.
．． It is composed of 4-butanediol residues in a specific component ratio, and has unprecedented flexibility, transparency, heat resistance, and moldability.

From the polyester of the present invention, fibers, films, sheets, and other molded products can be obtained that have good flexibility, transparency, and heat resistance, and whose properties change little over time. In particular, since the polyester of the present invention has a high crystallization rate, it can be easily molded into films, sheets, and other molded products.

[Brief explanation of the drawing]

FIG. 1 is an infrared absorption spectrum diagram of the polyester of Example 1 of the present invention.

Claims (1)

[Scope of Claims] In the repeating units constituting the polyester, the acid component is an aromatic dicarboxylic acid residue and the residue consisting of a long-chain aliphatic dicarboxylic acid with a molecular weight of 140 or more, and the glycol component is an ethylene glycol residue and 1,4 −
A polyester comprising butanediol residues and having a component ratio of each component expressed by the following formula. 50 mol%≦A≦95 mol% 5 mol%≦B≦50 mol% 35 mol%≦C≦60 mol% 40 mol%≦D≦65 mol% (However, A is the component ratio of aromatic dicarboxylic acid residues , B is the component ratio of residues consisting of long-chain aliphatic dicarboxylic acids with a molecular weight of 140 or more, C is the component ratio of ethylene glycol residues, D
is the component ratio of 1,4-butanediol residue. )