JPH08325366A - Polyester amide sulfide elastomer - Google Patents

Abstract

PURPOSE: To obtain a new elastomer, (shape-) memory resin excellent in injection molding characteristics and useful as a heat-shrinkable tube by formulating an equimolecular mixture of 2 kinds of specific compounds to an polyester resin and then polymerizing them in the molten state. CONSTITUTION: This elastomer is obtained by mixing 100 pts.wt. of (A) an aromatic polyester resin (preferably a polybutylene terephthalate copolymer modified with 10-35 molar % of comonomer based on the base resin) with 30-120 pts.wt. of an equimolecular mixture of a compound of the formula (B) [R is an alkylene, arylene; R1 , R2 are each a (substituted) alkylene] (preferably 2,2'-m- phenylene bis(2-oxazoline) and (C) a dithiol compound (preferably 4,4'- thiobisbenzenthiol) then allowing the mixture to react in molten state of A. The molar ratio of the component (B) to the component (C) is preferably 0.95-1.05. Several kinds of fillers may be formulated while the amount of fillers is 1-80wt.% of the total composition including the objective resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel shape memory resin having excellent injection moldability, and provides a resin useful for applications such as a heat shrinkable tube and a joint material for different diameter pipes.

[0002]

2. Description of the Related Art Recently, the problems to be solved by the invention
With the fact that shape memory alloys have begun to be actually applied in various fields, the shape of the shape memory alloys has been closely watched, and various shape memory resins have been developed. However, under the present circumstances, no one having excellent moldability has been developed, and there is no resin that can be injection molded.

[0003]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have synthesized aromatic polyester resins, particularly polyalkylene terephthalate resins, and bisoxazoline compounds and dithiol compounds as raw materials. The thermoplastic elastomer has excellent injection moldability, and remembers the shape at the time of molding, deforms it to a predetermined shape at a deformation process temperature of room temperature plus 20 ° C or more and melting point or less, and cools it to about room temperature before use. At this time, the present invention was completed by discovering that the resin is a shape memory molding resin that can restore the memory shape by heating it again to the deformation process temperature. That is, according to the present invention, 100 to 100 parts by weight of an aromatic polyester resin is mixed with 30 to 120 parts by weight of a substantially equimolar mixture of a bisoxazoline compound and a dithiol compound, and the mixture is reacted under melting of the aromatic polyester resin. It is a polyester amide sulfide elastomer.

The present invention will be described in detail below. The aromatic polyester resin used in the present invention is a polyester resin containing an aromatic carboxylic acid and its ester-forming derivative and glycols as main starting materials, and particularly, a polyethylene terephthalate resin, a polybutylene terephthalate resin, and the like. Alkylene terephthalate is preferable, and among them, polybutylene terephthalate resin is preferable in consideration of the balance of crystallinity, crystallization rate, heat resistance, mechanical strength and the like. Also, for the base resin
It is more preferable to use the copolyester resin modified with 10 to 35 mol% of the comonomers because the process temperature at the time of production can be lowered. As the copolymer component,
Phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,
Aromatic dicarboxylic acids and derivatives thereof such as 4′-diphenyldicarboxylic acid, adipic acid, sebacic acid, aliphatic dicarboxylic acids and derivatives thereof such as succinic acid, trimesic acid, aromatic tricarboxylic acids such as trimellitic acid and derivatives thereof, Aromatic hydroxycarboxylic acids such as hydroxybenzoic acid and hydroxynaphthoic acid and their derivatives, low molecular weight glycols such as ethylene glycol, propanediol, butenediol and hexanediol, high molecular weight glycols such as polyethylene oxide glycol and polybutylene oxide glycol, bisphenol A, bisphenol S, 4,4'-hydroxydiphenyl and other aromatic diols and their ethylene oxide, propylene oxide adducts, pentaerythritol and other polyhydroxy compounds, and the like. That. The above-mentioned polyester, the monomer raw material, and, using a polycondensation catalyst such as titanium tetrabutoxide, by applying the polycondensation method of polyester generally performed, in the molten state, in the solid state, or Both can be manufactured in combination.

The bisoxazoline compound used as the starting material compound of the present invention is represented by the following general formula (1).

[0006]

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(R is an alkylene group, a substituted alkylene group,
A divalent organic group selected from an arylene group and a substituted arylene group, R ₁ and R ₂ are alkylene groups or substituted alkylene groups, preferably ethylene groups or propylene groups) represented by the general formula (1) Specific examples of the bisoxazoline compound include 2,2′-methylenebis (2-oxazoline),
2,2'-ethylenebis (2-oxazoline), 2,2'-ethylenebis (4-methyl-2-oxazoline), 2,2'-propylenebis (2-oxazoline), 2,2'-tetramethylene Bis (2-oxazoline), 2,2'-hexamethylenebis (2-oxazoline), 2,2'-octamethylenebis (2-oxazoline), 2,2'-p-phenylenebis (2
-Oxazoline), 2,2'-p-phenylenebis (4-methyl-2-oxazoline), 2,2'-p-phenylenebis (4,4-dimethyl-2-oxazoline), 2,2'-p -Phenylene bis (4-phenyl-2-oxazoline), 2,
2'-m-phenylene bis (2-oxazoline), 2,2'-
m-phenylene bis (4-methyl-2-oxazoline), 2,2'-m-phenylene bis (4,4-dimethyl-2)
-Oxazoline), 2,2'-m-phenylenebis (4-phenyl-2-oxazoline), 2,2'-o-phenylenebis (2-oxazoline), 2,2'-phenylbis (4-methyl- 2-oxazoline), 2,2'-bis (2-oxazoline), 2,2'-bis (4-methyl-2-oxazoline), 2,2'-bis (4-ethyl-2-oxazoline),
2,2'-bis (4-phenyl-2-oxazoline) and the like can be mentioned. Such bisoxazoline compounds may be used alone or in combination of two or more. Of these bisoxazoline compounds, the preferred one is R
Is an arylene group, more preferably a phenylene group. Particularly preferred is 2,2'-m-phenylene bis (2-oxazoline).

Next, the dithiol compound used in the present invention is represented by the general formula HS-R ₅ -SH (in the formula, R ₅ is an aliphatic hydrocarbon group which may have a heteroatom or a heteroatom. Represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent). Examples of the aliphatic hydrocarbon group of the aliphatic hydrocarbon group which may have a hetero atom include methylene, ethylene, propylene, butylene, hexamethylene, dodecyl methylene and the like alkylene groups having 1 to 15 carbon atoms. . Specific examples of the compound include ethylenedithiol and butylenedithiol. Further, examples of the aliphatic hydrocarbon group through a hetero atom include those having oxygen and the like as a hetero atom such as diethylene glycol residue and dibutylene glycol residue, and specific compounds include: Examples thereof include mercapto-substituted acyloxydithiol compounds such as ethylene glycol bisthioglycolate and butylene glycol bisthioglycolate. The aromatic hydrocarbon group of the aromatic hydrocarbon group which may have a hetero atom,
Examples thereof include arylene groups having 6 to 14 carbon atoms such as phenylene, tolylene, xylylene, biphenylene and naphthylene. Specific examples include o-dimercaptobenzene and m-
Dimercaptobenzene, p-dimercaptobenzene, o
-Dimercaptotoluene, m-dimercaptotoluene,
p-dimercaptotoluene, 2,4'-thiobisbenzenethiol, 4,4'-thiobisbenzenethiol and the like can be mentioned. In addition, examples of the aromatic hydrocarbon group through a hetero atom include bisphenylene ether, bisphenylenesulfonyl, bis (propoxyphenylpropane), and the like, and specific compounds include bis (4′-mercaptophenyl). ) Ether, 2,2′-bis (2-hydroxy-3-mercaptopropoxyphenylpropane) and the like.

The aromatic heterocyclic group which may have a substituent includes a 5-membered to 6-membered ring containing 1 to 4 hetero atoms (eg, nitrogen, sulfur, etc.). .
A 6-membered ring is preferable, and for example, a triazine group or a thiadiazole group is used. The triazine group may have a substituent, and examples of the substituent include a lower alkyl group such as methyl, ethyl, propyl and butyl, a phenyl group, a substituted aryl group such as alkylphenyl and aminophenyl, amino and alkylamino, Substituted amino groups such as dialkylamino and the like can be mentioned. Specific compounds include 6-dibutylamino-1,3,5-triazine-2,4-dithiol,
6-aminophenyl-1,3,5-triazine-2,4-dithiol, 2,5-dimercapto-1,2,4-thiadiazole and the like can be mentioned. These dithiol compounds may be used alone or in combination. Among the dithiol compounds, 4,4'-
Thiobisbenzenethiol, 6-dibutylamino-1,3,
5-triazine-2,4-dithiol and 6-aminophenyl-1,3,5-triazine-2,4-dithiol are preferably used.

When blending the bisoxazoline compound and the dithiol compound into the aromatic polyester, unless the molar numbers of the bisoxazoline compound and the dithiol compound are substantially equal to each other, a large amount of unreacted low molecular weight substance is left in the resin after the reaction. Therefore, it is necessary to be careful because it will remain in the product and deteriorate the physical properties. The term "substantially equimolar" as used herein means that the molar ratio of the bisoxazoline compound to the dithiol compound is in the range of 0.9 to 1.1, preferably 0.95 to 1.05. Also,
When this mixture is blended with an aromatic polyester resin for melt reaction, if the blending amount of the above equimolar mixture is less than 30 parts by weight per 100 parts by weight of the aromatic polyester resin, the shape memory performance is inferior. If the number is too large, the shape memory performance is poor and injection molding becomes difficult. The reaction rate of the aromatic polyester and the bisoxazoline compound and the dithiol compound under melting is extremely fast, and the reaction is completed immediately if melt kneading at a temperature above these melting points,
The thermoplastic elastomer can be produced by a kneading device such as a melt polymerization reactor equipped with a stirrer or a Henschel mixer, or a uniaxial or biaxial extruder. Regarding the degree of polymerization of the polyester amide sulfide elastomer of the present invention, when hexafluoroisopropanol is used as a measurement solvent and the measurement temperature is 30 ° C., the range in which the intrinsic viscosity is 0.7 or more and 2.0 is from the moldability and physical property balance. preferable. The order of mixing the respective components is not particularly limited, and an equimolar mixture of the bisoxazoline compound and the dithiol compound may be added to the molten polyester, or the bisoxazoline compound and the dithiol compound may be sequentially added.

The polyester amide sulfide elastomer of the present invention may be blended with various fibrous, powdery or plate-like inorganic and organic fillers depending on the purpose of use. As the fibrous filler, glass fiber, asbestos fiber, silica fiber, silica-alumina fiber, alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber, and further stainless steel, aluminum, titanium Inorganic fibrous substances such as metal fibrous substances such as copper, copper and brass. A particularly representative fibrous filler is glass fiber. In addition, polyamide resin, fluororesin,
High melting point organic fibrous substances such as polyester resin and acrylic resin can also be used. On the other hand, as the particulate filler, carbon black, graphite, silica, quartz powder,
Glass beads, milled glass fiber, glass balloon, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, silicates such as wollastonite, iron oxide, titanium oxide, zinc oxide, trioxide Antimony, metal oxides such as alumina, calcium carbonate,
Examples thereof include carbonates of metals such as magnesium carbonate, sulfates of metals such as calcium sulfate and barium sulfate, other ferrites, silicon carbide, silicon nitride, boron nitride, and various metal powders. Examples of the plate-like filler include mica, glass flakes, various metal foils and the like. As examples of organic fillers, aromatic polyester fibers, liquid crystalline polymer fibers,
It is a heat-resistant high-strength synthetic fiber such as aromatic polyamide or polyimide fiber. These inorganic and organic fillers can be used alone or in combination of two or more. The combined use of the fibrous filler and the powdery or plate-like filler is a preferable combination particularly in terms of mechanical strength, dimensional accuracy, electrical properties and the like. The amount of the filler compounded is 95 with respect to the total amount of the composition.
It is not more than weight%, preferably 1 to 80 weight%. When using these fillers, it is desirable to use a sizing agent or a surface treatment agent if necessary. If necessary, antioxidants, ultraviolet absorbers, photoprotectors, phosphite stabilizers, peroxide decomposers, basic auxiliaries, nucleating agents, plasticizers, lubricants, antistatic agents, hardeners Additives such as a flame retardant and a colorant may be added in any amount within a range that does not impair the physical properties of the present invention.

[0012]

The present invention will be described below with reference to examples.
The present invention is not limited to these examples. Production Example 1 61.7 parts by weight of dimethyl terephthalate (DMT), 26.5 parts by weight of dimethyl isophthalate (DMI), and 49.1 parts by weight of 1,4-butylene glycol (BG) together with a predetermined amount of a transesterification catalyst (tetrabutyl titanate). After charging a reactor equipped with a stirrer and a distilling tube and sufficiently replacing with nitrogen,
The temperature was raised to 160 ° C under normal pressure and stirring was started. Furthermore, the temperature was gradually raised and the by-product methanol was distilled off. When the temperature reached 240 ° C, the reactor was gradually depressurized and stirring was continued for 2 hours at a pressure of 0.2 torr to obtain a copolymerized polyester (I) having MI of 46. Production Example 2 The same operation as in Production Example 1 was performed except that DMT was 66.1 parts by weight and DMI was 22.0 parts by weight to obtain a copolyester (II) having an MI of 45.

Example 1 Copolymerized polyester (I) 50 parts by weight, 2,2'-m-phenylenebis (2-oxazoline) (1,3-PBO) (manufactured by Takeda Yakuhin) 29.5 parts by weight, 2,5- When 20.5 parts by weight of dimercapto-1,3,4-thiadiazole (bismuthiol: BMT) was kneaded with a Labo Plastomill manufactured by Toyo Seiki, the torque increase was completed within 1 minute, and a polyesteramide sulfide elastomer was obtained. The obtained elastomer was subjected to ¹ H-NMR measurement using trifluoroacetic acid-d as a measurement solvent, and unreacted monomer was not observed, and it was confirmed that the copolymerization composition was expected from the charged amount. . The melting point was taken as the melting point peak temperature at a heating rate of 10 ° C./min by DSC measurement. For MI, a test temperature of 235 ° C. and a test load of 2.16 kg were obtained. JIS K6 for tensile strength and elongation
Measured by 361. Shape fixability: width 5 mm, thickness 2
A test piece having a length of 10 mm and a length of 10 mm was molded by a hot press, folded back 180 ° at a temperature of 80 ° C., cooled to 20 ° C. as it is, and shown as a return angle. Then, the test piece was heated again to 80 ° C., and the recovery rate of the turning angle was defined as the shape recovery property. Separately, this resin was injection-molded at a mold temperature of 80 ° C., and the injection-moldability was visually evaluated. The results are shown in the table. Examples 2 to 5 and Comparative Examples 1 to 4 Reactions were performed in the same manner as in Example 1 with the compositions shown in Table 1, and the obtained resins were evaluated in the same manner. The disnet DB used as the dithiol compound is 6-dibutylamino-1,3,5-triazine-2,4-dithiol manufactured by Sankyo Kasei Co., Ltd. Further, the copolymerized elastomer A shown in Table 1
The structural formulas of ~ D are as follows.

[0014]

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[0015]

[Table 1]

Claims (6)

[Claims] 1. To 100 parts by weight of an aromatic polyester resin,
A polyester amide sulfide elastomer obtained by mixing 30 to 120 parts by weight of a substantially equimolar mixture of a bisoxazoline compound and a dithiol compound, and reacting the mixture under the melting condition of an aromatic polyester resin. 2. The polyester amide sulfide elastomer according to claim 1, wherein the aromatic polyester resin is a polyalkylene terephthalate resin. 3. The polyalkylene terephthalate resin, wherein the main skeleton is polybutylene terephthalate.
The described polyesteramide sulfide elastomer. 4. A polyalkylene terephthalate resin,
Mainly polyalkylene terephthalate 10-35 mol%
The polyester amide sulfide elastomer according to claim 2 or 3, which is a copolymer modified with another copolymerizable monomer. 5. The polyesteramide sulfide elastomer according to claim 1, wherein the bisoxazoline compound is phenylene bisoxazoline. 6. The polyester sulfide elastomer according to claim 1, which has a shape memory property.