JPH0768375B2 - Polyester elastomer sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a polyester elastomer sheet (including a film and a plate-like body) made of an aliphatic polyester.

(Prior Art) As a method for producing a polyester elastomer sheet of this type, for example, Japanese Patent Publication No. 1-49741 discloses a temperature of 140 ° C.
A method has been proposed in which a crystalline polyester elastomer having the above melting point is melt-formed into a sheet shape, and then rolled in the width direction and simultaneously rolled and heat-treated in the length direction. According to such a method, a sheet having higher tensile strength and tear strength than an unstretched sheet can be obtained.

(Problems to be Solved by the Invention) However, in the sheet obtained in the above publication, polyester having a relatively high melting point and crystallinity is used, and polyethylene terephthalate and poly are used as hard segments of the elastomer. Since an aromatic polyester such as butylene terephthalate is used, physical properties such as tensile breaking strength and elongation of the sheet are insufficient, and there is room for improvement.

The present invention has been made by paying attention to the above situation,
An object of the invention is to provide a polyester elastomer sheet in which physical properties such as tensile breaking strength and elongation are further improved as compared with conventional sheets.

(Means for Solving the Problems) In the polyester elastomer sheet of the present invention, an aliphatic dicarboxylic acid having a general formula represented by the following formula [I]; an aliphatic diol; and a dihydroxy compound having a general formula represented by the following formula [II] A compound and a monohydroxy compound represented by the following formula [III] are obtained by melt-molding an aliphatic polyester containing at least one of the components as a sheet, rolling or stretching the sheet, and then heat-treating the sheet. ,
Thereby, the above object is achieved.

HOOC- (CH ₂₎ n-COOH (I) (wherein, n represents an integer of 0.) (In the formula, R ¹ and R ² independently represent an alkylene group, and p is 3
Or 4, and q and r each independently represent 0 or an integer of 1 or more. ) (In the formula, R ³ represents an alkylene group, l is 2 or 3, and m is 0 or an integer of 1 or more.).

In the aliphatic dicarboxylic acid used in the present invention, if a dicarboxylic acid having more than 10 carbon atoms is used, the physical properties of the sheet formed from the polyester elastomer are deteriorated.
As the dicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, and sebacic acid are preferably used.

Examples of the aliphatic diol include glycol and polyalkylene oxide. Examples of the glycol include ethylene glycol, propylene glycol, trimethylene glycol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, cyclopentane-1,2-diol, cyclohexane-1,2-
Examples thereof include diol, cyclohexane-1,3-diol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol and the like, which may be used alone,
Two or more kinds may be used in combination.

Examples of the polyalkylene oxide include polyethylene oxide, polypropylene oxide, polytetramethylene oxide, polyhexamethylene oxide, and the like.
These may be used alone or in combination of two or more. The number average molecular weight of polyalkylene oxide is
When it becomes smaller, the ability to impart flexibility to the resulting polyester elastomer decreases, and when it becomes too large, physical properties such as thermal stability of the obtained polyester elastomer decrease, so 100 to 20,000 is preferable, and 500 is more preferable.
~ 5,000.

The dihydroxy compound represented by the above formula [II] is a low molecular weight compound exhibiting liquid crystallinity, the alkylene groups R ¹ and R ² are preferably ethylene groups or propylene groups, q and r are preferably 0 or 1, and 4 4,4 ″ -dihydroxy-p-terphenyl, 4,4-dihydroxy-p-quaterphenyl, 4,4-di (2-hydroxyethoxy) -p-quaterphenyl and the like are preferably used.

The transition temperature from the crystalline state of 4,4 ″ -dihydroxy-p-terphenyl to the liquid crystal state is 260 ° C., that of 4,4-dihydroxy-p-quaterphenyl is 336 ° C., 4,4-di (2-hydroxy). (Ethoxy) -p-quaterphenyl has a temperature of 403 ° C. The liquid crystal state means a state in which the compound is in a molten state and molecules are in an aligned state. These may be used alone or in combination.

Liquid crystal molecules generally have high crystallinity, and as described above, 4,
4 ″ -dihydroxy-p-terphenyl, 4,4-dihydroxy-p-quaterphenyl and 4,4-di (2-
Since hydroxyethoxy) -p-quaterphenyl and the like have a high transition point from the crystal to the liquid crystal state, when these dihydroxy compounds [II] are incorporated into the polymer chain, the polymer shows unique properties.

That is, since the dihydroxy compound [II] exhibits crystallinity and its transition point is high, the dihydroxy compound [II]
Even when the compounding amount of is small, it forms a physical crosslink that is stronger and has higher heat resistance than conventional aromatic polyesters such as polyethylene terephthalate. As a result, it is presumed that a polyester elastomer having excellent physical properties such as tensile strength, tear strength and elongation can be obtained without impairing the flexibility derived from the soft segment.

The monohydroxy compound represented by the above formula [III] is a rigid low-molecular compound having a paraphenylene skeleton, and the melting point of these compounds is extremely high, reflecting the characteristic molecular structure. Further, the paraphenylene skeleton is known to be effective as a mesogen for low-molecular liquid crystal compounds, and it has a strong cohesive force not only in the solid state but also in the high temperature state (molten state). Is shown. Therefore, when the above-mentioned monohydroxy compound [III] is incorporated into the polymer terminal, a polyester elastomer excellent in physical properties is obtained, which brings about physical crosslinking that is extremely strong and has high heat resistance as compared with conventional aromatic polyesters such as polyethylene terephthalate. Is generated.

In the monohydroxy compound represented by the above formula [III], R ³ is preferably an ethylene group or a propylene group,
n is preferably 0 or 1. Examples of the monohydroxy compound include 4-hydroxy-p-terphenyl, 4-hydroxy-p-quaterphenyl and 4- (2
-Hydroxyethoxy) -p-terphenyl, 4- (2
-Hydroxyethoxy) -p-quaterphenyl and the like. The monohydroxy compounds [III] may be used alone or in combination.

Polyester elastomer comprising at least one of the above-mentioned aliphatic dicarboxylic acid [I], aliphatic diol and dihydroxy compound [II] and monohydroxy compound [III], and a poly-silicone having two hydroxyl groups, a lactone, and Aromatic hydroxycarboxylic acid may be contained as a constituent component.

The above-mentioned poly-silicone has two hydroxyl groups, and a poly-silicone having two hydroxyl groups at the molecular ends is preferable. For example, dimethyl polysiloxane having two hydroxyl groups at both ends of the molecule, diethyl polysiloxane,
Examples thereof include diphenylpolysiloxane. If the number average molecular weight of the polysilicone is small, the ability to impart flexibility to the polyester elastomer produced is reduced,
When it becomes large, it becomes difficult to produce a polyester elastomer, so 100 to 20,000 is preferable, and 5 is more preferable.
It is from 00 to 5,000.

The lactone is one that opens a ring and reacts with an acid and a hydroxyl group to add an aliphatic chain, imparts flexibility to the polyester elastomer, and has 4 or more carbon atoms in the ring. Preferred are those having a 5-membered ring to an 8-membered ring, and examples thereof include ε-caprolactone, δ-valerolactone, γ-butyrolactone and the like.

The aromatic hydroxycarboxylic acid imparts rigidity and liquid crystallinity to the polyester elastomer, and is salicylic acid, metahydroxybenzoic acid, parahydroxybenzoic acid, 3-chloro-4-hydroxybenzoic acid, 3-bromo-4-. Hydroxybenzoic acid, 3-methoxy-4-hydroxybenzoic acid, 3-methyl-4-hydroxybenzoic acid,
3-phenyl-4-hydroxybenzoic acid, 2-hydroxy-6-naphthoic acid, 4-hydroxy-4'-carboxybiphenyl and the like can be mentioned, preferably para-hydroxybenzoic acid, 2-hydroxy-6-naphthoic acid, 4-
Hydroxy-4'-carboxybiphenyl.

Further, the polyester elastomer may contain an aromatic diol other than the dihydroxy compound [II] or an aromatic dicarboxylic acid as a constituent component in order to improve mechanical properties and the like.

Examples of the aromatic diol include hydroquinone, resorcin, chlorohydroquinone, bromohydroquinone, methylhydroquinone, phenylhydroquinone, methoxyhydroquinone, phenoxyhydroquinone, 4,4′-dihydroxybiphenyl, 4,4′-dihydroxydiphenyl ether, 4,4′- Dihydroxydiphenyl sulfide, 4,
4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxybenzophenone, 4,4'-dihydroxydiphenylmethane, bisphenol A, 1,1-di (4-hydroxyphenyl) cyclohexane, 1,2-bis (4-hydroxyphenoxy) Examples thereof include ethane, 1,4-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene.

Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, metal salts of 5-sulfoisophthalic acid, 4,4′-
Dicarboxybiphenyl, 4,4'-dicarboxydiphenyl ether, 4,4'-dicarboxydiphenyl sulfide, 4,4'-dicarboxydiphenyl sulfone, 3,
3'-dicarboxybenzophenone, 4,4'-dicarboxybenzophenone, 1,2-bis (4-carboxyphenoxy) ethane, 1,4-dicarboxynaphthalene, or
2,6-dicarboxynaphthalene and the like can be mentioned.

A polyester elastomer composed of the above dihydroxy compound [II], an aliphatic diol and an aliphatic dicarboxylic acid,
When the content of the dihydroxy compound [II] is low, the heat resistance is low, and when the content is high, the elastic modulus is high and the flexibility is low, which makes the polyester elastomer unsuitable. Is 0.1 to 3 in all the monomers constituting the polyester elastomer.
0 mol% is preferable, more preferably 0.5 to 20 mol%, and further preferably 1.0 to 10 mol%. When polyalkylene oxide or polysilicone is used as a diol other than aromatic, its constituent unit is counted as one monomer. That is, polyethylene oxide having a degree of polymerization of 10 is counted as 10 monomers.

Further, the polyester elastomer comprising the above monohydroxy compound [III], an aliphatic diol and an aliphatic dicarboxylic acid has a low heat resistance when the content of the monohydroxy compound [III] is low, and when the content is high, the molecular weight of the polyester elastomer is sufficient. Since it does not increase and the physical properties become inferior, it is preferably 0.1 to 20 mol% in all the monomers constituting the polyester elastomer. Further, the polyester elastomer comprising the dihydroxy compound [II], the monohydroxy compound [III], the aliphatic diol and the aliphatic dicarboxylic acid contains a hydroxy compound obtained by combining the dihydroxy compound [II] and the monohydroxy compound [III]. When the amount is too small, the heat resistance is lowered, and when it is too large, the flexibility is not lowered and the molecular weight is not sufficiently increased. Therefore, it is preferably 0.1 to 30 mol% in all the monomers constituting the polyester elastomer. In this case, the ratio of the dihydroxy compound [II] and the monohydroxy compound [III] is preferably in the range satisfying 0 <[III] / [II] + [III] <2/3.

The polyester elastomer composed of the above components can be produced by any generally known polycondensation method. For example, a method in which a dicarboxylic acid and a diol component (including an aliphatic diol, a dihydroxy compound, a monohydroxy compound, etc.) are directly reacted, or a lower ester of dicarboxylic acid is reacted with a diol component by transesterification. Method, reaction of halide of dicarboxylic acid and diol component in a suitable solvent such as pyridine, method of reacting metal alcoholate of diol component with halide of dicarboxylic acid, ester of acetylated diol component and dicarboxylic acid There is a method of reacting using exchange.

In the polycondensation, a catalyst generally used in producing polyester may be used. As the catalyst, lithium, sodium, potassium, cesium, magnesium, calcium, barium, strontium, zinc, aluminum, titanium, cobalt, germanium,
Examples thereof include metals such as tin, lead, antimony, arsenic, cerium, boron, cadmium and manganese, organometallic compounds thereof, organic acid salts, metal alkoxides and metal oxides.

Particularly preferred catalysts are calcium acetate, diacyl stannous, tetraacyl stannic acid, dibutyltin oxide, dibutyltin dilaurate, dimethyltin malate, tin dioctanoate, tin tetraacetate, triisobutylaluminum, tetrabutyltitanate, germanium dioxide, and tris. It is antimony oxide. Two or more kinds of these catalysts may be used in combination. In addition, water, alcohol, glycol, etc., which are by-products of the polymerization, are efficiently distilled off,
In order to obtain a high molecular weight polymer, the reaction system is
It is preferable to reduce the pressure to 1 mm Hg or less. The reaction temperature is generally 150 to 350 ° C.

It is also possible to control the structure of the polyester elastomer obtained by changing the addition order of the dihydroxy compound [II] during the polymerization. For example, when the dihydroxy compound [II] is charged together with the dicarboxylic acid and other diol components, a random copolymer is easily obtained, and when the dihydroxy compound [II] is charged in the latter stage of the polymerization, the block copolymerization It becomes easier to obtain a coalesce. Also,
It is also possible to knead the above-mentioned dihydroxy compound [II] or the acetyl compound of the dihydroxy compound to polyester synthesized in advance under reduced pressure and introduce a segment based on the dihydroxy compound [II] into the molecular chain by deethylene glycol or transesterification reaction. Is.

The aliphatic polyester thus obtained is an elastomer having excellent heat resistance and mechanical properties, and particularly excellent in flexibility, impact resistance, cold resistance and the like.

The aliphatic polyester used in the present invention may be a mixture of a plurality of types of aliphatic polyester such as a combination of two or more types of aliphatic polyester having different soft segments.
Also, a small amount of a branched component such as trimellitic acid or glycerin may be copolymerized, or an aliphatic polyester obtained by blocking the terminal carboxy group of the aliphatic polyester with epoxy or the like may be used. .

The aliphatic polyester thus obtained is usually
It is formed into a sheet by melt extrusion, and the obtained sheet is rolled or stretched. The rolling or stretching may be uniaxial or biaxial. When the sheet is rolled, it can be performed mainly by using a rolling roll and, if necessary, a take-up roll, and the rolling ratio is preferably about 2 to 7 times in the longitudinal direction and about 1 to 2 times in the lateral direction. The temperature of the sheet during rolling is usually in the range of not lower than the glass transition point of the aliphatic polyester and lower than the melting point thereof by at least 30 ° C., preferably from room temperature to at least 50 ° C. lower than the melting point.

Stretching of the sheet can be usually carried out using a take-up roll, the stretching ratio is preferably 2 to 10 times, and the temperature during stretching can be set in the same manner as in the above rolling.

The rolled or stretched sheet needs to be heat-treated so that the sheet does not undergo dimensional change when used in a high temperature atmosphere and further, does not cause performance deterioration. The heat treatment temperature is preferably higher than the use temperature in consideration of the use environment of the sheet, but if the heat treatment is performed at a temperature that is too close to the melting point of the aliphatic polyester, the rolling or stretching effect will be relaxed, so It is preferable to keep the temperature at about 20 ° C. or lower.

The sheet made of the above aliphatic polyester does not have a so-called necking phenomenon, and the entire sheet can be stretched uniformly even at a magnification of about 2 to 3 times, and about 5 to 8 times after being stretched at that magnification. Tensile drawing (or rolling)
Since the strength of the sheet can be increased to a level comparable to that of the sheet, the creep phenomenon does not occur under high temperature and high load.

(Example) Below, this invention is demonstrated based on an Example.

Comparative Example To a monomer mixture of 871 g (5.0 mol) of dimethyl adipate, 744 g (12.0 mol) of ethylene glycol and 169 g (0.5 mol) of 4,4-dihydroxy-p-quaterphenyl,
200 g of antimony trioxide and calcium acetate as catalyst
Add 800g and a small amount of hindered phenol type stabilizer,
The reaction system was kept under nitrogen at 200 ° C. for 2 hours to carry out a transesterification reaction. Next, this reaction system was heated to 320 ° C. in 30 minutes, kept at this pressure for 1 hour under normal pressure, and then subjected to condensation reaction for 2 hours under reduced pressure of 1 mm Hg or less.

The intrinsic viscosity [η] of the obtained aliphatic polyester was 1.50 when measured using an Ubbelohde viscometer in an o-chlorophenyl solvent at 30 ° C.

Next, the obtained aliphatic polyester was melt extruded from a T die at a temperature of 260 ° C. to obtain a film-like product,
3mm thickness by passing through a chill roll kept at ℃
To obtain an unrolled sheet.

The obtained sheet was punched out into JIS K6301 No. 3 dumbbells and molded, and according to ASTM D638 Shimadzu Autograph AGB-
A tensile test was conducted at 5000 to determine the tensile breaking strength, tear strength and elongation at tensile breaking. The results are shown in Table 1.

Example 1 An unrolled sheet (thickness 3 m obtained in the same manner as in Comparative Example)
m) is heated through a preheating chamber set at 80 ° C and then 100
While being stretched 1.2 times in the width direction between the rolling rolls heated to ℃, it was rolled 2.5 times in the longitudinal direction.

The longitudinal magnification was adjusted by changing the peripheral speed ratio of the rolling roll and the take-up roll, and the widthwise magnification was adjusted by the pressing pressure of the rolling roll.

Next, the rolled sheet was heat-set by passing it through a 160 ° C. heating chamber adjacent to the take-up roll at a constant speed. At this time, the sheet feeding speed was 15 m / mm, and the heat setting time was 2 minutes.

The physical properties of the obtained elastomer sheet were measured. The results are shown in Table 1. The tensile rupture strength and the elongation at tensile rupture are the values obtained by pulling the sheet in the longitudinal direction, and the tear strength is the value obtained by pulling the sheet in a direction orthogonal to it.

Example 2 An unrolled sheet (thickness 3 m obtained in the same manner as in Comparative Example)
m) was uniaxially stretched 5 times at 100 ° C. and then heat set at 160 ° C. for 2 minutes as in Example 1.

The physical properties of the obtained elastomer sheet were measured. The results are shown in Table 1.

(Effect of the invention) Since the polyester elastomer sheet of the present invention has higher crystallinity than conventional polyesters and is composed of an aliphatic polyester having a hard segment based on a terphenyl compound or a quarterphenyl compound having a high melting point, When the elastomer is rolled or stretched and then heat treated, the hard segments are oriented to form strong physical crosslinks. Therefore, for example, it is possible to provide a sheet excellent in heat resistance, mechanical properties, etc., which does not cause a creep phenomenon even when used at a place where a heavy load acts or at high temperature.

Front page continued (72) Inventor Akihiro Niki 1-5-16 Jonan-cho, Takatsuki-shi, Osaka Bell Maison 301 (72) Inventor Torasuke Saito 5-17-21 Yamatedai, Ibaraki-shi, Osaka (72) Inventor Hiroki Kadomachi 1-11-3 Minamikasugaoka, Ibaraki-shi, Osaka (72) Inventor Daishiro Kishimoto 2-11-20 Mishima-oka, Ibaraki-shi, Osaka Umeyama Mansion 102

Claims (1)

[Claims] 1. An aliphatic dicarboxylic acid having a general formula represented by the following formula [I]; an aliphatic diol; and a general formula having the following formula [I]:
I) and a dihydroxy compound represented by the following formula [III] monohydroxy compound represented by at least one of the aliphatic polyester as a constituent component after melt molding into a sheet, then the sheet is rolled or stretched, then a polyester elastomer sheet obtained by _{heat-treating: HOOC- (CH 2) n-} COOH (I) (wherein, n represents an integer of 0.) (In the formula, R ¹ and R ² independently represent an alkylene group, and p is 3
Or 4, and q and r each independently represent 0 or an integer of 1 or more. ) (In the formula, R ³ represents an alkylene group, l is 2 or 3, and m is 0 or an integer of 1 or more.).