JPH06144433A - Polyester container - Google Patents

Abstract

PURPOSE:To decrease the amount of resin in a polyester container while increasing the strength of the container by making the container by stretched blow molding with a specified compound added to polyester resin. CONSTITUTION:A resin composition obtained by adding a compound shown in a formula I or a compound shown in a formula III in 0.1-10 pts.wt. to polyester resin in 100 pts.wt. is molded by stretched blow molding. In the formula I, R stands for alkyl group or alkoxyl group, and R'stands for hydrocarbon group, m and n are the integers with which m+n becomes not less than 0 and not more than 3, p and r are the integers with which p+r becomes 1 or 2, q is 0 or 1 and X is either one of those which are in the formula II. R1 and R2 in the formula II stand respectively for H or alkyl group with carbons in 4 or below. B1 and B2 in the formula III stand for alkyl group or alkoxyl group respectively with carbons in numbers from not less than 3 to not more than 18, A stands for dialiphatic hydrocarbon group, dialicyclic hydrocarbon group or diaromatic hydrocarbon group. When making stretched blow molding, magnification of planate stretching is four times or more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent polyester container having excellent strength, which is effective when higher strength than usual is required or when the resin amount is reduced to reduce the wall thickness. is there.

[0002]

2. Description of the Related Art Polyethylene terephthalate (PET), which is a typical polyester resin, is usually molded into a container by a method called biaxially stretch blow molding, which is excellent in transparency and mechanical strength and has a gas barrier. It is widely used as a container material with relatively good properties.

On the other hand, in recent years, environmental problems have been highlighted, utilization of environment-friendly materials, resource saving, energy saving,
Recycling, etc. are being clamored for. From the viewpoint of resource saving, it is desirable to reduce the amount of resin and develop a thin container. However, if the amount of PET resin is extremely reduced, the strength is insufficient and it is necessary to increase the strength. One of the methods for increasing the strength is to increase the molecular weight, but increasing the molecular weight alone is not enough to increase the effect, and the melt viscosity becomes high, which lowers the productivity of the injection process for making preforms. .

[0004]

The inventors of the present invention have conducted extensive studies to solve the above problems. As a result, when a specific compound is added to a polyester resin and stretch blow molding is performed, the strength of the polyester container is improved. However, they have found that it is possible to reduce the amount of resin in the container, and have completed the present invention. That is, the present invention relates to 100 parts by weight of the polyester resin,

[0005]

[Chemical 4]

(In the formula, R is an alkyl group or an alkoxy group, and R'is a hydrocarbon group. M and n are m + n of 0 or more and 3
The following integers, p and r are integers such that p + r is 1 or 2, q is 0 or 1, and X is

[0007]

[Chemical 5]

One of the above. Here, R ₁ ,
Each R ₂ represents H or an alkyl group having 4 or less carbon atoms. ) Or a compound represented by the general formula (II)

[0009]

[Chemical 6]

(In the formula, B ₁ and B ₂ each have 3 or more carbon atoms 18
The following alkyl groups or alkoxy groups are shown, and A is a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group. ) The compound represented by
It is intended to provide a polyester container characterized by being stretch blow molded from a resin composition obtained by adding 10 parts by weight.

In the compound represented by the general formula (I) according to the present invention, the total carbon number of R and R'is preferably selected within the range of the following formula (III). _{9 ≦ N R × (m +} n) + N R '× (p + r) ≦ 56 (III) ( wherein, N _R is the number of carbon atoms of the substituent R, N _R' represents the number of carbon atoms of the substituent R '.) R If the total number of carbon atoms in R, R'is less than 9, the molecular weight may be too low and the polyester may scatter at the melting temperature of the polyester, failing to exhibit sufficient performance, or foaming may occur in the container, greatly reducing the physical properties of the container. . Further, if the total number of carbon atoms of R and R'exceeds 56, the compatibility with the resin deteriorates and the effect cannot be exhibited, which is not preferable. From the viewpoint of increasing the compatibility of the compounds, the total number of carbon atoms of R and R'is more preferably 36 or less.

R is specifically a methyl group, an ethyl group, n
-Propyl group, n-butyl group, n-hexyl group, n-octyl group, n-decyl group, n-dodecyl group, n-tetradecyl group, n-hexadecyl group, n-octadecyl group,
Linear alkyl groups such as n-eicosyl group and n-docosyl group, iso-propyl group, sec-propyl group, iso-butyl group, sec-butyl group, tert-butyl group, iso-pentyl group, neo-pentyl group Group, tert-pentyl group, 2-ethylhexyl group, 1-hexylnonyl group, 1-butylpentyl group, methyl branched heptadecyl group, 1,1,3,3-tetramethylbutyl group, 1,3,5-trimethylhexyl group Base, 1,3,
A branched alkyl group such as a 5,7-tetramethyloctyl group, further, an n-propoxy group, an n-butoxy group, an n-hexyloxy group, an n-octyloxy group, an n-decyloxy group, an n-dodecyloxy group, Examples thereof include an alkoxy group such as a 2-ethylhexyloxy group.

R'is specifically a methyl group, an ethyl group, n
-Propyl group, n-butyl group, n-hexyl group, n-pentyl group, n-heptyl group, n-nonyl group, n-undecyl group, n-tridecyl group, n-pentadecyl group, n-
Linear alkyl groups such as heptadecyl group, n-nonadecyl group, and n-heneicosyl group, 1-hexylnonyl group, 1
-Butyl pentyl group, branched alkyl groups such as methyl branched heptadecyl group, saturated alkyl groups such as cycloalkyl group such as cyclohexyl group, 8-heptadecenyl group, 9-decenyl group, benzyl group, 2-phenylethyl group and the like. be able to.

In particular, in the general formula (I), m and n are each 0, and p and r are each 1
The compound represented by (IV) is preferable.

[0015]

[Chemical 7]

(Here, X and q have the same meanings as described above, and B ₃ and B ₄ represent a hydrocarbon group.) In the general formula (IV), the carbon number of B ₃ and B ₄ is 5 or more 21 The following is desirable. B ₃ , B ₄
If the number of carbon atoms is less than 5, the molecular weight is too low, and it may boil at the polyester melting temperature to generate bubbles. Also, B ₃ , B ₄
If the number of carbon atoms in the compound exceeds 21, the compatibility with the resin deteriorates and the effect is insufficient.

B ₃ and B ₄ are specifically n-pentyl group, n
-Heptyl group, n-nonyl group, n-undecyl group, n-
Linear alkyl groups such as tridecyl group, n-pentadecyl group, n-heptadecyl group, n-nonadecyl group, and n-heneicosyl group, and branched alkyl groups such as 1-hexylnonyl group, 1-butylpentyl group and methyl-branched heptadecyl group. Groups, saturated alkyl groups such as cycloalkyl groups such as cyclohexyl groups, 8-heptadecenyl groups, 9-decenyl groups, benzyl groups, 2-phenylethyl groups and the like.

Further, in the compound represented by the general formula (II) according to the present invention, the carbon number of B ₁ , B ₂ and A can be arbitrarily selected within the above range. Preferably, the total carbon number of B ₁ , B ₂ , and A is 6 or more and 40 or less. If the total number of carbon atoms of B ₁ , B ₂ and A is less than 6, the molecular weight is too low, which may cause scattering at the melting temperature of the polyester or foaming to significantly deteriorate the physical properties of the container. Further, if the total number of carbon atoms of B ₁ , B ₂ and A exceeds 40, the compatibility with the resin deteriorates and the effect is insufficient, which is not preferable.

B ₁ and B ₂ are specifically n-propyl group, n
-A straight-chain alkyl group such as butyl group, n-hexyl group, n-octyl group, n-decyl group, n-dodecyl group, n-tetradecyl group, n-hexadecyl group, n-octadecyl group, or iso-propyl group , Sec-propyl group, iso-butyl group, sec-butyl group, tert-butyl group, iso-pentyl group, neo-pentyl group, tert-pentyl group, 2-ethylhexyl group, 1-hexylnonyl group, 1-butyl Pentyl group, methyl branched heptadecyl group, 1,1,3,3-tetramethylbutyl group, 1,3,5-trimethylhexyl group, 1,3,
Branched alkyl groups such as 5,7-tetramethyloctyl group, cyclic alkyl groups such as cyclohexyl group, and further n-propoxy group, n-butoxy group, n-hexyloxy group, n-octyloxy group, n-decyloxy group Group, n-
Examples thereof include alkoxy groups such as -dodecyloxy group and 2-ethylhexyloxy group.

In the general formula (II), A is a divalent aliphatic hydrocarbon group which may have a straight chain or a branched chain,
A divalent alicyclic hydrocarbon group which may have a substituent or a divalent aromatic hydrocarbon group which may have a substituent, and specifically,-(CH ₂ ) ₂ −, − (CH ₂ ) ₃ −, − (CH ₂ )
_{4 -, - (CH 2)} 6 -, - (CH 2) 8 -,

[0021]

[Chemical 8]

And the like. The compound represented by formula (I) according to the present invention can be easily obtained by a known method. That is, the following equation (V)

[0023]

[Chemical 9]

(Wherein X and q have the same meanings as described above), for example, biphenyl,
Diphenyl ether, diphenyl sulfide, etc. are reacted with an α-olefin having 3 to 18 carbon atoms or an alkyl halide having 1 to 18 carbon atoms in the presence of a Lewis acid catalyst such as aluminum chloride, and then further reacted with a carboxylic acid anhydride or a carboxylic acid. It can be obtained by similarly reacting a chloride or carboxylic acid in the presence of a Lewis acid catalyst such as aluminum chloride and acylating.

Further, the compound represented by the general formula (I) according to the present invention, wherein R is an alkoxy group, is prepared by converting the corresponding phenolic compound into a halogenated alkyl compound in the presence of an alkali catalyst such as NaOH or KOH. It is also obtained by reacting with a carboxylic acid anhydride, a carboxylic acid chloride, or a carboxylic acid in the presence of a Lewis acid catalyst such as aluminum chloride to acylate.

Among the compounds represented by the general formula (I), the compound represented by the general formula (IV) is a Friedel compound of the corresponding aromatic compound and carboxylic acid, carboxylic acid anhydride or carboxylic acid chloride. It is easily obtained by the Krafts reaction. For example, it can be obtained by reacting biphenyl, diphenyl ether or diphenyl sulfide with a carboxylic acid chloride in the presence of a Lewis acid such as AlCl ₃ and acylating. The compound represented by the general formula (II) according to the present invention has the following formula (VI)

[0027]

[Chemical 10]

(Wherein A has the same meaning as described above), an acid halide or acid anhydride of a dicarboxylic acid is used, and alkylbenzene or alkoxybenzene is used in a Friedel-Crafts reaction with a Lewis acid as a catalyst. It is easily obtained by acylation. The method for synthesizing the compound of the present invention is not limited to the above method, and any known method can be used.

Specific examples of the compound represented by formula (I) or (II) according to the present invention are as follows.

[0030]

[Chemical 11]

[0031]

[Chemical 12]

[0032]

[Chemical 13]

[0033]

[Chemical 14]

The compound represented by the above general formula (I) or (II) is uniformly added to and mixed with the polyester resin, and does not emit smoke or color even when exposed to a high temperature during melt molding. It has almost no heat resistance.

In order to improve the strength in the present invention, 0.1 to 10 parts by weight, preferably 0.5 to 10 parts by weight of the compound represented by the above general formula (I) or (II) is added to 100 parts by weight of the raw material polyester resin. It is necessary to add ~ 8 parts by weight. If it is less than 0.1 part by weight, the effect can hardly be expected, and if it exceeds 10 parts by weight, the physical properties of the container are adversely affected.

The compound represented by the general formula (I) or (II) may be added at a suitable step during or after the production of the polyester resin. When added after production, for example, single-screw extruder, twin-screw extruder, open roll,
Either a melt-blending method using a kneader, a mixer, or the like, or a dry-blending method with a polyester resin before molding into a container may be used.

The polyester resin used in the present invention may be any resin as long as it has high stretchability, but a polyester resin containing ethylene terephthalate or ethylene 2,6-naphthalate as a main repeating unit is preferably used. The polyester resin having ethylene terephthalate or ethylene 2,6-naphthalate as a main repeating unit used in the present invention may contain another ester repeating unit in an amount of less than 10 mol%. Dicarboxylic acid components other than terephthalic acid and 2,6-naphthalenedicarboxylic acid include isophthalic acid, 1,5-, 1,6-, and 1,7-
-, 2,7-naphthalenedicarboxylic acid, phthalic acid, cyclohexanedicarboxylic acid, dibromoisophthalic acid, sodium-sulfoisophthalic acid, diphenyldicarboxylic acid,
Aromatic dicarboxylic acids such as diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, diphenyl ketone dicarboxylic acid, diphenoxyethane dicarboxylic acid, phenylenedioxydiacetic acid, adipic acid, sebacic acid, succinic acid, glutaric acid, piperic acid, suberic acid, Examples thereof include aliphatic dicarboxylic acids such as azelaic acid, undecadioic acid, dodecadioic acid, and the like, or a mixture of two or more kinds.

As diol components other than ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, decamethylene glycol, propylene glycol, neopentyl glycol, diethylene glycol, polyethylene glycol, etc. Aliphatic glycols, cycloaliphatic glycols such as cyclohexanedimethanol, o, m, p-xylylene glycol, aromatic glycols such as 2,2-bis (4-hydroxyethoxyphenyl) propane, etc., alone or in combination of two or more. A mixture may be mentioned.

Further, a hydroxycarboxylic acid such as glycolic acid, hydroxybenzoic acid or hydroxynaphthoic acid,
You may copolymerize diphenols, such as hydroquinone, resorcinol, dihydroxydiphenyl, and dihydroxydiphenyl ether. Regarding the molecular weight of the polyester resin, the intrinsic viscosity at 25 ° C. in phenol / tetrachloroethane (60:40, weight ratio) (hereinafter abbreviated as [η]) is
It is preferably 0.6 or more, and if less than 0.6, the strength of the container may be insufficient.

In the present invention, the container molding method is preferably biaxial stretch blow molding which is used when a polyethylene terephthalate (PET) container is manufactured. The preform (preform) is once taken out and then stretch blown in another step. Any of a method called a cold parison method for forming and a method called a hot parison method in which a step of forming a preform and a step of stretch blow molding are continuous can be adopted. In the present invention, the effect is small only by adding the compound represented by the general formula (I) or (II), and the effect of the present invention is achieved only after stretch blow molding.

In the present invention, when the stretching ratios in the longitudinal and transverse directions are calculated from the longitudinal and lateral dimensional ratios excluding the unstretched mouth of the preform and the product is defined as the areal stretching ratio, the areal stretching ratio is used in the present invention. Is preferably four times or more. When it is less than 4 times, the degree of strength increase is small as compared with the case where the compound represented by the general formula (I) or (II) is not added.
Although the mechanism by which the strength is increased in the present invention is not clear, it is considered that the addition of the compound represented by the general formula (I) or (II) facilitates the orientation of the polyester resin during stretching.

Further, the compound represented by the general formula (I) or (II) also has the property of lowering the melt viscosity, and has the advantage that the processability in the injection step of molding a preform is improved and the productivity is improved. There is also. If necessary, various additives such as colorants, oxidation stabilizers, ultraviolet absorbers, antistatic agents, flame retardants and the like can be added to the resin composition as the raw material of the container of the present invention.

[0043]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited to these examples. In the examples, "part" is based on weight unless otherwise specified.

Examples 1 to 10 Polyethylene terephthalate resin ([η] = 0.9 dl /
g) Add 3 parts of the compound shown in Table 1 to 100 parts, and
After drying for 4 hours, the mixture was melt-kneaded at 270 to 280 ° C. using a twin-screw extruder, and the obtained strand was cooled with water and cut into pellets. After drying the pellets at 140 ℃ for 4 hours, the part excluding the mouth is 20 mm in outer diameter, 85 mm in length, and weighs
A 23 g preform (preform) was injection molded. The molding conditions at that time are the cylinder temperature setting value of 280
℃, the mold set temperature was 20 ℃. Subsequently, biaxial stretch blow molding was performed at 110 ° C. to form a cylindrical container having a capacity of 1 liter, a body diameter of 90 mm, a height excluding the mouth portion of 160 mm, and a mouth diameter of 20 mm.

The draw ratio of this container is 1.9 times in the longitudinal direction, 4.5 times in the transverse direction, and the area drawing ratio is 8.6 times. An injection blow molding machine manufactured by Nissei ASB Machine Co., Ltd. was used as a molding machine. Using the obtained container, the drop strength and the tensile strength were measured by the following methods. The results are shown in Table 1.

<Test method> Drop strength: The container was filled with water, capped with a cap, and then naturally dropped from a height of 1 m onto the concrete surface. Ten containers were dropped up to 10 times and evaluated by the number of times two (20%) cracked. -Tensile strength The container was cut open and a test piece was made with dumbbell No. 3. Using Orientec Tensilon UCT-100, the stress was measured while pulling at a constant speed of 10 mm / min, and the yield stress, the breaking stress and the elastic modulus were determined.

Comparative Example 1 A polyethylene terephthalate resin alone was molded in the same manner as in Examples 1 to 10, and the physical properties were evaluated in the same manner. The results are shown in Table 1.

[0048]

[Table 1]

Example 11 Using the compound (1) of the present invention, the same operation as in Examples 1 to 10 was carried out while changing the addition amount as shown in Table 2,
A test similar to 10 was conducted. The results are shown in Table 2.

[0050]

[Table 2]

Examples 12 to 21 Polyethylene terephthalate resin ([η] = 0.9 dl /
g) To 100 parts, 3 parts of the same compounds as in Examples 1 to 10 were added, molded in the same manner as in Examples 1 to 10 except for the shape of the preform and the container, and evaluated. The outer diameter of the preform
28mm, length 90mm, weight 32g, container size is capacity
A cylindrical container having a volume of 600 ml, a body diameter of 60 mm, a height excluding the mouth portion of 200 mm, and a mouth diameter of 27 mm was molded. The stretching ratio of this container is 2.2 times in the longitudinal direction, 2.1 times in the lateral direction, and 4.6 times in the areal stretching ratio. The evaluation results are shown in Table 3.

Comparative Example 2 A polyethylene terephthalate resin alone was molded in the same manner as in Examples 12 to 21, and the physical properties were evaluated in the same manner. The results are shown in Table 3.

[0053]

[Table 3]

Example 22 Using the compound (1) of the present invention, the same operations and tests as in Examples 12 to 21 were carried out by changing the addition amount as shown in Table 4. The results are shown in Table 4.

[0055]

[Table 4]

Examples 23 to 32 Polyethylene 2,6-naphthalate resin ([η] = 0.81 dl / g) was used as the polyester resin instead of polyethylene terephthalate resin, and 3 parts of the same compound as in Examples 1 to 10 was added. Then, it was molded and evaluated in the same manner as in Examples 1-10. Molding conditions at that time are set value of cylinder temperature 2
The temperature was 90 ° C, the mold temperature was 20 ° C, and the biaxial stretching blow temperature was 130 ° C. The evaluation results are shown in Table 5.

Comparative Example 3 Polyethylene 2,6-naphthalate resin alone Examples 23-
Molded in the same manner as 32, and evaluated the physical properties in the same manner. The results are shown in Table 5.
Shown in.

[0058]

[Table 5]

Example 33 Using the compound (1) of the present invention, the same operations and tests as in Examples 23 to 32 were carried out by changing the addition amount as shown in Table 6. The results are shown in Table 6.

[0060]

[Table 6]

[0061]

The polyester container of the present invention is effective when higher strength than usual is required or when the resin amount is reduced to reduce the wall thickness, and can contribute to resource saving.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location C08L 67/02 KJU 8933-4J // B29K 67:00 B29L 22:00 4F

Claims (3)

[Claims] 1. A compound represented by the general formula (I): (In the formula, R represents an alkyl group or an alkoxy group, R ′ represents a hydrocarbon group. M and n are integers in which m + n is 0 or more and 3 or less, p and r are integers in which p + r is 1 or 2, and q is 0 or 1, X is Is one of: Here, R ₁ and R ₂ each represent H or an alkyl group having 4 or less carbon atoms. ) Or a compound represented by the general formula (II): (In the formula, B ₁ and B ₂ each represent an alkyl group or an alkoxy group having 3 to 18 carbon atoms, A is a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group or a divalent A polyester container obtained by stretch blow molding a resin composition obtained by adding 0.1 to 10 parts by weight of a compound represented by an aromatic hydrocarbon group. 2. A compound represented by the general formula (I) has R 1,
The polyester container according to claim 1, which is a compound in which the total number of carbon atoms of R'is within the range of the following formula (III). _{9 ≦ N R × (m +} n) + N R '× (p + r) ≦ 56 (III) ( wherein, N _R is the number of carbon atoms of the substituent R, N _R' represents the number of carbon atoms of the substituent R '.) 3. Stretch blow molding, wherein the surface stretching ratio is 4 times or more.
The described polyester container.