JP4935347B2 - Heat resistant corrugated tube - Google Patents

Description

    The present invention relates to a corrugated tube used for the purpose of protecting conductive wires of automobiles and electrical products, and particularly relates to a heat-resistant corrugated tube excellent in heat resistance, heat aging resistance, water resistance, and low temperature characteristics.

Conventionally, corrugated tubes are used for the purpose of protecting electric wires by storing electric wires and cables (hereinafter referred to as conductive wires) of automobiles and electric products. For example, when bundling conductive wires in a place where the temperature is high, such as in an engine room of an automobile, the copper wire coating material is not exposed to high temperatures to melt with heat or swell with oil. In other words, a method of storing the conductive wire in the corrugated tube is employed.
As a material used for the corrugated tube, not only heat resistance and oil resistance are required to prevent the above problems, but also properties such as flexibility are required for the corrugated tube material. Therefore, polyolefin materials are generally used. In areas where heat resistance is high, polyester elastomer materials, polyamide materials, fluorine materials, and the like are used.

  As thermoplastic polyester elastomers used for heat-resistant applications, crystalline polyesters such as polybutylene terephthalate (PBT) and polybutylene naphthalate (PBN) have been used as hard segments, and polytetramethylene glycol (PTMG), etc. Polyesters such as polyoxyalkylene glycols and / or polycaprolactone (PCL) and polybutylene adipate (PBA) are known and put into practical use (for example, Patent Documents 1 and 2).

In recent years, corrugated tube materials with higher heat resistance have been desired. However, conventional polyester elastomers have poor water resistance and heat aging resistance, and polyamide elastomers have poor flexibility, and swell with high temperature oils and chemicals. Is remarkable. In the case of a polyurethane elastomer, the swelling of oil is slightly lower than that of other elastomers, but there is a problem that the softening temperature is low. On the other hand, the fluororesin has a problem that flexibility is impaired under a low temperature environment, and the required performance cannot be satisfied.
Therefore, conventional thermoplastic elastomers have not been able to satisfy the recent demand for the corrugated tube market.
Japanese Patent Laid-Open No. 10-17657 JP 2003-192778 A

In view of the above-mentioned problems of the prior art, the present invention provides at least a thermoplastic polyester elastomer having excellent heat resistance, heat aging resistance, water resistance, light resistance, low temperature characteristics, etc. and having excellent blockability retention. The object is to provide a heat-resistant corrugated tube used for one or more of the components.
In the present invention, the use of the thermoplastic polyester elastomer for at least one or more of the tube components is that it is one or more of the constituent components, or in the case of a multilayer structure, that it is used for one or more of the layer structures. .

The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention for achieving the above object is a hard segment composed mainly of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol, and mainly an aliphatic polycarbonate. A polyester elastomer formed by bonding soft segments comprising the thermoplastic polyester elastomer, using a differential scanning calorimeter of the thermoplastic polyester elastomer, heated from room temperature to 300 ° C. at a heating rate of 20 ° C./min, and at 300 ° C. for 3 minutes. The melting point difference between the melting point (Tm1) obtained by the first measurement and the melting point (Tm3) obtained by the third measurement when the cycle of lowering the temperature to room temperature at a temperature lowering rate of 100 ° C./min is repeated three times after holding. (Tm1-Tm3) is 0-50 ° C. and the tensile strength at the time of cutting is 15-100 M It is a thermoplastic polyester elastomer, which is a a.
In this case, it is preferable that the hard segment is composed of a polybutylene terephthalate unit, and the melting point of the obtained elastomer is 200 to 225 ° C.
Moreover, in this case, it is preferable that the hard segment is composed of a polybutylene naphthalate unit, and the melting point of the obtained elastomer is 215 to 240 ° C.
In this case, when the average chain length (x) of the hard segment and the average chain length (y) of the soft segment calculated using the nuclear magnetic resonance method (NMR method) are used, the average chain length of the hard segment (x ) Is 5 to 20, and the block property (B) calculated by the following formula (1) is preferably 0.11 to 0.45.
B = 1 / x + 1 / y (1)
Further, in this case, it is preferable that the polyester is made by reacting a polyester composed of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol with an aliphatic polycarbonate diol having a molecular weight of 5000 to 80000 in a molten state.

  The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention has good heat resistance and maintains the characteristics of the polyester polycarbonate type elastomer that is excellent in heat aging resistance, water resistance, low temperature characteristics, etc. Block property and block property retention are improved. Due to the high block property, a decrease in heat resistance due to a decrease in melting point is suppressed, and mechanical properties such as hardness, tensile strength and elastic modulus are improved. In addition, the improvement of the block property holding property suppresses the fluctuation of the block property during the molding process, so that the uniformity of the quality of the molded product can be enhanced. In addition, recyclability is enhanced by the characteristics, which can lead to environmental load and cost reduction. In addition, the heat-resistant corrugated tube of the present invention is preferably used as a corrugated tube used for automobiles, home appliance parts, etc., which are required to have heat aging resistance, water resistance, and low-temperature characteristics, particularly around automobile engines. Can do.

Hereinafter, the thermoplastic polyester elastomer used for the heat-resistant corrugated tube of the present invention will be described in detail.
In the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention, the aromatic dicarboxylic acid constituting the hard segment polyester is widely used as an ordinary aromatic dicarboxylic acid, and is not particularly limited, but as the main aromatic dicarboxylic acid Is preferably terephthalic acid or naphthalenedicarboxylic acid. Other acid components include diphenyl dicarboxylic acid, isophthalic acid, aromatic dicarboxylic acid such as 5-sodium sulfoisophthalic acid, cycloaliphatic dicarboxylic acid, alicyclic dicarboxylic acid such as tetrahydrophthalic anhydride, succinic acid, glutaric acid, adipine Examples thereof include aliphatic dicarboxylic acids such as acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, and hydrogenated dimer acid. These are used within a range that does not significantly lower the melting point of the resin, and the amount thereof is less than 30 mol%, preferably less than 20 mol% of the total acid component.

  Further, in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention, the aliphatic or alicyclic diol constituting the hard segment polyester is widely used as a general aliphatic or alicyclic diol, and particularly limited. Although it is not, it is desirable that it is mainly C2-C8 alkylene glycol. Specific examples include ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol and the like. Most preferred are 1,4-butanediol and 1,4-cyclohexanedimethanol.

  The component constituting the hard segment polyester is preferably a butylene terephthalate unit or a butylene naphthalate unit from the viewpoint of physical properties, moldability, and cost performance.

  Moreover, the aromatic polyester suitable as polyester which comprises the hard segment in the thermoplastic polyester elastomer used for the heat resistant corrugated tube of this invention can be easily obtained according to the manufacturing method of a normal polyester. Moreover, what has the number average molecular weight 10000-40000 is desirable for this polyester.

  Moreover, it is preferable that the aliphatic polycarbonate which comprises the soft segment in the thermoplastic polyester elastomer used for the heat resistant corrugated tube of this invention mainly consists of a C2-C12 aliphatic diol residue. Examples of these aliphatic diols include ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 2, 2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,9-nonanediol, 2-methyl-1,8- Examples include octanediol. In particular, aliphatic diols having 5 to 12 carbon atoms are preferable from the viewpoint of flexibility and low temperature characteristics of the obtained thermoplastic polyester elastomer. These components may be used alone or in combination of two or more as required, based on the case described below.

  As an aliphatic polycarbonate diol having a low temperature characteristic and constituting a soft segment of the thermoplastic polyester elastomer used in the heat-resistant corrugated tube in the present invention, the melting point is low (for example, 70 ° C. or less) and the glass transition temperature is low. Those are preferred. In general, an aliphatic polycarbonate diol composed of 1,6-hexanediol used to form a soft segment of a thermoplastic polyester elastomer has a low glass transition temperature of around -60 ° C and a melting point of around 50 ° C. Good low temperature characteristics. In addition, an aliphatic polycarbonate diol obtained by copolymerizing an appropriate amount of, for example, 3-methyl-1,5-pentanediol with the above aliphatic polycarbonate diol has a glass transition point with respect to the original aliphatic polycarbonate diol. Although the melting point is slightly increased, the melting point is lowered or becomes amorphous, so that it corresponds to an aliphatic polycarbonate diol having good low-temperature characteristics. Moreover, for example, an aliphatic polycarbonate diol composed of 1,9-nonanediol and 2-methyl-1,8-octanediol has a melting point of about 30 ° C. and a glass transition temperature of about −70 ° C., which is sufficiently low. Corresponds to aliphatic polycarbonate diol with good low-temperature properties.

  The above-mentioned aliphatic polycarbonate diol is not necessarily composed of only the polycarbonate component, and may be obtained by copolymerizing a small amount of other glycol, dicarboxylic acid, ester compound or ether compound. Examples of copolymer components include, for example, dimer diols, hydrogenated dimer diols and glycols such as modified products thereof, dicarboxylic acids such as dimer acid and hydrogenated dimer acid, aliphatic, aromatic, and alicyclic dicarboxylic acids Examples thereof include polyesters or oligoesters composed of glycol, polyesters or oligoesters composed of ε-caprolactone, polyalkylene glycol such as polytetramethylene glycol, polyoxyethylene glycol, or oligoalkylene glycol.

  The copolymer component can be used to such an extent that the effect of the aliphatic polycarbonate segment is not substantially lost. Specifically, it is 40 parts by mass or less, preferably 30 parts by mass or less, more preferably 20 parts by mass or less with respect to 100 parts by mass of the aliphatic polycarbonate segment. When the amount of copolymerization is too large, the resulting thermoplastic polyester elastomer has poor heat aging resistance and water resistance.

  The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention is a soft segment, for example, polyalkylene glycol such as polyethylene glycol or polyoxytetramethylene glycol, polycaprolactone, polybutylene, as long as the effects of the invention are not lost. A copolymer component such as polyester such as adipate may be introduced. The content of the copolymer component is usually 40 parts by mass or less, preferably 30 parts by mass or less, and more preferably 20 parts by mass or less with respect to 100 parts by mass of the soft segment.

  In the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention, the mass part ratio of the polyester constituting the hard segment and the aliphatic polycarbonate and copolymer component constituting the soft segment is generally determined as follows: hard segment: soft segment = 30:70 to 95: 5, preferably 40:60 to 90:10, more preferably 45:55 to 87:13, and most preferably 50:50 to 85:15.

The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention is composed of a hard segment composed of a polyester composed of the above aromatic dicarboxylic acid and an aliphatic or alicyclic diol, and a soft composed mainly of an aliphatic polycarbonate. A polyester elastomer in which segments are bonded. Here, the term “bonded” means that the hard segment and the soft segment are not bonded by a chain extender such as an isocyanate compound, but the units constituting the hard segment and the soft segment are directly bonded by an ester bond or a carbonate bond. The state is preferable.
For example, it is preferable to obtain the polyester constituting the hard segment, the polycarbonate constituting the soft segment, and if necessary, various copolymerization components while melting and repeating the transesterification reaction and depolymerization reaction for a certain period of time (hereinafter referred to as blocking reaction). Sometimes called).

  The blocking reaction is preferably performed at a temperature within the range of the melting point of the polyester constituting the hard segment to the melting point + 30 ° C. In this reaction, the concentration of the active catalyst in the system is arbitrarily set according to the temperature at which the reaction is carried out. That is, since the transesterification and depolymerization proceed rapidly at higher reaction temperatures, it is desirable that the active catalyst concentration in the system be low, and that there is some concentration of active catalyst at lower reaction temperatures. It is desirable that

  The catalyst may be an ordinary catalyst such as titanium compounds such as titanium tetrabutoxide and potassium oxalate titanate, or one or more tin compounds such as dibutyltin oxide and monohydroxybutyltin oxide. The catalyst may be pre-existing in the polyester or polycarbonate, in which case it need not be added anew. Furthermore, the catalyst in the polyester or polycarbonate may be partially or substantially completely deactivated in advance by any method. For example, when titanium tetrabutoxide is used as a catalyst, for example, phosphorous acid, phosphoric acid, triphenyl phosphate, tristriethylene glycol phosphate, orthophosphoric acid, carbethoxydimethyl diethyl phosphonate, triphenyl phosphite, trimethyl phosphate, trimethyl phosphite, etc. The deactivation is performed by adding a phosphorus compound or the like, but is not limited thereto.

  The above reaction can be carried out by arbitrarily determining a combination of reaction temperature, catalyst concentration, and reaction time. That is, the appropriate values of the reaction conditions vary depending on various factors such as the types and amount ratios of the hard segments and soft segments to be used, the shape of the apparatus to be used, and the stirring conditions.

  The optimum value of the reaction conditions is, for example, when the melting point of the obtained chain extension polymer and the melting point of the polyester used as the hard segment are compared, and the difference is 2 ° C to 60 ° C. When the difference in melting point is less than 2 ° C., both segments are not mixed or / and reacted, and the resulting polymer exhibits inferior elastic performance. On the other hand, when the difference in melting point exceeds 60 ° C., the block property of the obtained polymer is lowered due to the remarkable progress of the transesterification reaction, and crystallinity, elastic performance and the like are lowered.

  It is desirable that the remaining catalyst in the molten mixture obtained by the above reaction is deactivated as completely as possible by any method. When the catalyst remains more than necessary, it is considered that the transesterification further proceeds during compounding or molding, and the physical properties of the obtained polymer fluctuate.

  This deactivation reaction is carried out in the above-described manner, for example, phosphorous acid, phosphoric acid, triphenyl phosphate, tristriethylene glycol phosphate, orthophosphoric acid, carboxydimethyl diethyl phosphonate, triphenyl phosphite, trimethyl phosphate, trimethyl phosphite, etc. Although it is carried out by adding a phosphorus compound or the like, it is not limited to this.

  The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention may contain a tri- or higher functional polycarboxylic acid or polyol only in a small amount. For example, trimellitic anhydride, benzophenone tetracarboxylic acid, trimethylolpropane, glycerin and the like can be used.

  Furthermore, the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention can be blended with various additives depending on the purpose to obtain a composition. Additives include known hindered phenol-based, sulfur-based, phosphorus-based, amine-based antioxidants, hindered amine-based, triazole-based, benzophenone-based, benzoate-based, nickel-based, salicyl-based light stabilizers, antistatic agents, etc. Agents, lubricants, molecular modifiers such as peroxides, epoxy compounds, isocyanate compounds, compounds having reactive groups such as carbodiimide compounds, metal deactivators, organic and inorganic nucleating agents, neutralizing agents, control agents Acid agents, antibacterial agents, fluorescent brighteners, fillers, flame retardants, flame retardant aids, organic and inorganic pigments, and the like can be added.

  As the hindered phenolic antioxidant that can be blended in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention, 3,5-di-t-butyl-4-hydroxy-toluene, n-octadecyl- β- (4′-hydroxy-3 ′, 5′-di-t-butylphenyl) propionate, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] Methane, 1,3,5-trimethyl-2,4,6'-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, calcium (3,5-di-t-butyl-4- Hydroxy-benzyl-monoethyl-phosphate), triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) Propionate], pentaerythrityl-tetrakis [3- (3,5-di-t-butylanilino) -1,3,5-triazine, 3,9-bis [1,1-dimethyl-2- {β- (3 -T-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane, bis [3,3-bis (4'-hydroxy- 3'-t-butylphenyl) butyric acid] glycol ester, triphenol, 2,2'-ethylidenebis (4,6-di-t-butylphenol), N, N'-bis [3- (3,5-di -T-butyl-4-hydroxyphenyl) propionyl] hydrazine, 2,2'-oxamidobis [ethyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,1 3-tris (3 ′, 5′-di-t-butyl-4′-hydroxybenzyl) -S-triazine-2,4,6 (1H, 3H, 5H) -trione, 1,3,5-tris ( 4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 3,5-di-tert-butyl-4-hydroxyhydrocinnamic atide triester with-1,3,5-tris ( 2-hydroxyethyl) -S-triazine-2,4,6 (1H, 3H, 5H), N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] Undecane Etc. can be mentioned.

  Examples of the sulfur-based antioxidant that can be blended in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention include dilauryl-3,3′-thiodipropionic acid ester and dimyristyl-3,3′-thiodiuropionic acid. Ester, distearyl-3,3′-thiodipropionate, laurylstearyl-3,3′-thiodipropionate, dilaurylthiodipropionate, dioctadecyl sulfide, pentaerythritol-tetra (β- Lauryl-thiopropionate) ester and the like.

  Examples of the phosphorus-based antioxidant that can be blended in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention include tris (mixed, mono and dinolylphenyl) phosphite, tris (2,3-di-). t-butylphenyl) phosphite, 4,4′-butylidene-bis (3-methyl-6-tert-butylphenyl-di-tridecyl) phosphite, 1,1,3-tris (2-methyl-4-di) -Tridecyl phosphite-5-t-butylphenyl) butane, tris (2,4-di-t-butylphenyl) phosphite, bis (2,4-di-t-butylphenyl) pentaerythritol-di-phos Phyto, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylene phosphanite, bis (2 6-di-t-butyl-4-methylphenyl) pentaerystol-di-phosphite, tetrakis (2,4-di-t-butylphenyl) 4,4′-biphenylene diphosphonite, triphenyl phosphite , Diphenyldecyl phosphite, tridecyl phosphite, trioctyl phosphite, tridodecyl phosphite, trioctadecyl phosphite, trinonylphenyl phosphite, tridodecyl trithiophosphite and the like.

  Examples of amine antioxidants that can be blended in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention include N, N-diphenylethylenediamine, N, N-diphenylacetamidine, and N, N-diphenylfluamidine. N-phenylpiperidine, dibenzylethylenediamine, triethanolamine, phenothiazine, N, N′-di-sec-butyl-p-phenylenediamine, 4,4′-tetramethyl-diaminodiphenylmethane, P, P′-dioctyl- Diphenylamine, N, N′-bis (1,4-dimethyl-pentyl) -p-phenylenediamine, phenyl-α-naphthylamine, phenyl-β-naphthylamine, 4,4′-bis (4-α, α-dimethyl-) Amines such as (benzyl) diphenylamine And reaction products of a derivative thereof or an amine and an aldehyde, can be mentioned a reaction product of amine and ketone.

  As a hindered amine light stabilizer that can be blended in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention, dimethyl-1- (2-hydroxyethyl) -4-hydroxy-2,2,6 oxalate is used. , 6-tetramethylpiperidine polycondensate, poly [[6- (1,1,3,3-tetrabutyl) imino-1,3,5-triazine-2,4-diyl] hexamethylene [(2, 2,6,6-tetramethyl-4-piperidyl) imyl]], bis (1,2,2,6,6-pentamethyl-4-piperidyl) ester of 2-n-butylmalonic acid, tetrakis (2,2 , 6,6-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, bis (2,2,6,6-tetramethyl-4-piperidyl) ) Sebacate, polycondensate of N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine and 1,2-dibromoethane, poly [(N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine)-(4-monoforino-1,3,5-triazine-2,6-diyl) -bis (3,3,5,5 -Tetramitylpiperazinone)], tris (2,2,6,6-tetramethyl-4-piperidyl) -dodecyl-1,2,3,4-butanetetracarboxylate, tris (1,2,2, 6,6-pentamethyl-4-piperidyl) -dodecyl-1,2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1,6, 11-Tris [{4 6-bis (N-butyl-N- (1,2,2,6,6-pentamethylpiperidin-4-yl) amino-1,3,5-triazin-2-yl) amino} undecane, 1- [ 2- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetromethylpiperidine, 8-benzyl-7,7,9,9-tetramethyl-3 -Octyl-1,3,8-triazaspiro [4,5] undecane-2,4-dione, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, N, N'-bis (3-amino Propyl) ethylenediamine-2,4-bis [N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, etc. Can be mentioned.

  The benzophenone-based, benzotriazole-based, triazole-based, nickel-based, and salicyl-based light stabilizers that can be blended in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention include 2,2′-dihydroxy-4- Methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, pt-butylphenyl salicylate, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate, 2 -(2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-amyl-phenyl) benzotriazole, 2- [2'-hydroxy-3 '5'-bis (α, α-dimethylbenzylphenyl) benzotriazole, 2- (2'- Roxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzazotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) -5-chlorobenzotyle Azole, 2,5-bis- [5'-t-butylbenzoxazolyl- (2)]-thiophene, bis (3,5-di-t-butyl-4-hydroxybenzyl phosphate monoethyl ester) nickel salt 2-ethoxy-5-t-butyl-2'-ethyloxalic acid-bis-anilide 85-90% and 2-ethoxy-5-t-butyl-2'-ethyl-4'-t-butyloxalic Mixture of 10-15% acid-bis-anilide, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2-ethoxy-2′-ethyloxazoly Quad bisanilide, 2- [2′-hydroxy-5′-methyl-3 ′-(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimido-methyl) phenyl] benzotriazole, bis ( 5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole, 2-hydroxy-4-i-octoxybenzophenone, 2-hydroxy- Examples thereof include light stabilizers such as 4-dodecyloxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, and phenyl salicylate.

  As a lubricant that can be blended with the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention, hydrocarbon, fatty acid, fatty acid amide, ester, alcohol, metal soap, natural wax, silicone And fluorine-based compounds. Specifically, liquid paraffin, synthetic paraffin, synthetic hard paraffin, synthetic isoparaffin petroleum hydrocarbon, chlorinated paraffin, paraffin wax, micro wax, low-polymerized polyethylene, fluorocarboxylic oil, lauric acid having 12 or more carbon atoms, myristic acid, Fatty acid compounds such as palmitic acid, stearic acid, arachidic acid, behenic acid, hexylamide, octylamide, stearylamide, palmitylamide, oleylamide, erucylamide, ethylenebisstearylamide, laurylamide, behenylamide, methylenebisstearylamide, C3-C30 saturated or unsaturated aliphatic amides and derivatives thereof such as ricinolamide, lower alcohol esters of fatty acids, polyhydric alcohol esters of fatty acids, polyglycols of fatty acids Steal, butyl stearate which is fatty alcohol ester of fatty acid, hydrogenated castor oil, ethylene glycol monostearate, etc., cetyl alcohol, stearyl alcohol, ethylene glycol, polyethylene glycol having a molecular weight of 200 to 10,000 or more, polyglycerol, carnauba wax, candelilla wax, montan wax And lubricants such as dimethyl silicone, silicon gum, and ethylene tetrafluoride. Also, a metal salt composed of a compound having a linear saturated fatty acid, a side chain acid, and cinnolic acid, wherein the metal is selected from (Li, Mg, Ca, Sr, Ba, Zn, Cd, Al, Sn, Pb) Can also be mentioned.

  Fillers that can be blended in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention include magnesium oxide, aluminum oxide, silicon oxide, calcium oxide, titanium oxide (rutile type, anatase type), chromium oxide ( (Trivalent), iron oxide, zinc oxide, silica, diatomaceous earth, alumina fiber, antimony oxide, barium ferrite, strontium ferrite, beryllium oxide, pumice, pumice balloon, and other oxides, manesium hydroxide, aluminum hydroxide, basic magnesium carbonate Basic substances such as hydroxide or hydroxide, or carbonates such as magnesium carbonate, calcium carbonate, barium carbonate, ammonium carbonate, calcium sulfite, dolomite, dosonite, or calcium sulfate, barium sulfate, ammonium sulfate (Sulphite) sulfates such as calcium sulfite and basic magnesium sulfate, or sodium silicate, magnesium silicate, aluminum silicate, potassium silicate, calcium silicate, talc, clay, mica, asbestos, glass fiber, montmorillonite, glass balloon, glass beads, Silicates such as pentonite or kaolin (ceramic clay), pearlite, iron powder, copper powder, lead powder, aluminum powder, tungsten powder, molybdenum sulfide, carbon black, boron fiber, silicon carbide fiber, brass fiber, potassium titanate, Examples include lead zirconate titanate, zinc borate, aluminum borate, barium metaborate, calcium borate, sodium borate and the like.

  Flame retardant aids that can be blended with the thermoplastic polyester elastomer used in the heat resistant corrugated tube of the present invention include antimony trioxide, antimony tetroxide, antimony pentoxide, sodium pyroantimonate, tin dioxide, zinc metaborate , Aluminum hydroxide, magnesium hydroxide, zirconium oxide, molybdenum oxide, red phosphorus compound, ammonium polyphosphate, melamine cyanurate, ethylene tetrafluoride and the like.

  Examples of the compound having a triazine group and / or a derivative thereof that can be blended with the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention include melamine, melamine cyanurate, melamate phosphate, and guanidine sulfamate.

  Examples of the inorganic phosphorus compound of the phosphorus compound that can be blended with the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention include red phosphorus compounds and ammonium polyphosphate. Examples of red phosphorus compounds include red phosphorus coated with a resin, and composite compounds with aluminum. Examples of organic phosphorus compounds include phosphate esters and melamine phosphate. Phosphate esters include phosphates, phosphonates, trimethyl phosphates of phosphinates, triethyl phosphate, tributyl phosphate, trioctyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, octyl diphenyl phosphate, tricresyl phosphate, Cresyl diphenyl phosphate, triphenyl phosphate, trixylenyl phosphate, tris-isopropylphenyl phosphate, diethyl-N, N-bis (2-hydroxyethyl) aminomethylphosphonate, bis (1,3-phenylenediphenyl) Phosphate, aromatic condensed phosphate ester 1,3- [bis (2,6-dimethylphenoxy) phosphenyloxy] benzene, 1,4- [bis 2,6-dimethyl-phenoxy) such as phosphorylase phenyloxy] benzene hydrolysis and heat stability, preferably a flame retardant.

  As a method for blending these additives, they can be blended using a kneader such as a heating roll, an extruder, or a Banbury mixer. Moreover, it can add and mix in the oligomer before the transesterification reaction or polycondensation reaction at the time of manufacturing a thermoplastic polyester elastomer resin composition.

  The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention is heated from room temperature to 300 ° C. at a rate of temperature increase of 20 ° C./min using a differential scanning calorimeter of the thermoplastic polyester elastomer, and 3 at 300 ° C. The melting point of the melting point (Tm1) obtained by the first measurement and the melting point (Tm3) obtained by the third measurement when the cycle of lowering the temperature to room temperature at a temperature lowering rate of 100 ° C./min is repeated three times after holding for 3 minutes. It is important that the difference (Tm1-Tm3) is 0-50 ° C. The melting point difference is more preferably 0 to 40 ° C, further preferably 0 to 30 ° C. The melting point difference is a measure of the blockability retention of the thermoplastic polyester elastomer. The smaller the temperature difference, the better the blockability retention. When the difference in melting point exceeds 50 ° C., the blockability retention is deteriorated, the quality fluctuation at the time of molding is increased, and the uniformity of the quality of the molded product is deteriorated and the recyclability is deteriorated.

  By satisfy | filling the said characteristic, the effect of the outstanding block property which the thermoplastic polyester elastomer used for the below-mentioned heat-resistant corrugated tube of this invention can be utilized effectively.

  In the thermoplastic polyester elastomer used for the heat-resistant corrugated tube of the present invention, it is preferable that the hard segment is composed of a polybutylene terephthalate unit, and the melting point of the obtained thermoplastic polyester elastomer is 200 to 225 ° C. 205-225 degreeC is more preferable.

  Moreover, in the thermoplastic polyester elastomer used for the heat-resistant corrugated tube of the present invention, it is preferable that the hard segment is composed of a polybutylene naphthalate unit, and the melting point of the obtained thermoplastic polyester elastomer is 215 to 240 ° C. 220-240 degreeC is more preferable.

  When the hard segment is a polybutylene terephthalate unit or a polybutylene naphthalate unit, a commercially available polyester such as polybutylene terephthalate or polybutylene naphthalate can be used, which is advantageous in terms of economy.

  Moreover, when the melting point of the thermoplastic polyester elastomer is less than the lower limit, the block property is lowered, and the heat resistance and mechanical properties of the thermoplastic polyester elastomer are deteriorated, which is not preferable. On the other hand, when the above upper limit is exceeded, the compatibility between the hard segment and the soft segment is lowered, and the mechanical properties of the thermoplastic polyester elastomer are deteriorated, which is not preferable.

  The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention has a polyester unit as a hard segment and an aliphatic polycarbonate unit as a ft segment, and has a repeating number of repeating units constituting one homopolymer structural unit. The average value is referred to as the average chain length. In the present specification, unless otherwise indicated, a value calculated using a nuclear magnetic resonance method (NMR method) is shown.

When the average chain length (x) of the hard segment and the average chain length (y) of the soft segment calculated using the nuclear magnetic resonance method (NMR method) are used, the average chain length (x) of the hard segment is 5 to 20 It is preferable that the block property (B) calculated by the following formula (1) is 0.11 to 0.45.
B = 1 / x + 1 / y (1)

  As for the thermoplastic polyester elastomer used for the heat resistant corrugated tube of this invention, the average chain length of the polyester unit which is a hard segment structural component has preferable 5-20. More preferably, it is 7-18, More preferably, it is the range of 9-16.

  In the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention, the average chain length (x) of the polyester unit of the hard segment is an important factor that determines the block property of the thermoplastic polyester elastomer. It greatly affects the melting point of polyester elastomer. Generally, as the average chain length (x) of the polyester units increases, the melting point of the thermoplastic polyester elastomer also increases. Further, the average chain length (x) of the polyester units of the hard segment is a factor that affects the mechanical properties of the thermoplastic polyester elastomer. When the average chain length (x) of the polyester unit of the hard segment is less than 5, it means that randomization has progressed, and the mechanical properties such as the decrease in heat resistance due to the decrease in melting point, hardness, tensile strength, elastic modulus, etc. Degradation of properties is large. When the average chain length (x) of the polyester unit of the hard segment is large, the compatibility with the aliphatic carbonate diol constituting the soft segment is lowered, causing phase separation, greatly affecting the mechanical properties, and its strength. , Reduce the elongation.

Moreover, it is preferable that block property (B) is 0.11-0.45. 0.13-0.40 is more preferable and 0.15-0.35 is still more preferable. As the value increases, the block property decreases. When the block property exceeds 0.4, the polymer properties such as the melting point of the thermoplastic polyester elastomer being lowered due to the block property decline are not preferable. On the other hand, if it is less than 0.10, the compatibility between the hard segment and the soft segment is lowered, causing deterioration of mechanical properties such as strong elongation and bending resistance of the thermoplastic polyester elastomer and an increase in fluctuation of the properties. Therefore, it is not preferable.
Here, the block property is calculated by the following equation (1).
B = 1 / x + 1 / y (1)

From the above relationship, the average chain length (y) of the soft segment is preferably 4-15.
Only when the above block property is satisfied, it is possible to achieve both high heat resistance and mechanical properties.

In the present invention, the method for bringing the above-mentioned blockability retention and blockability into the above ranges is not limited, but it is preferable to optimize the molecular weight of the polycarbonate diol as a raw material. That is, it is preferably produced by reacting the polyester constituting the hard segment in the above-described thermoplastic polyester elastomer of the present invention with an aliphatic polycarbonate diol having a molecular weight of 5000 to 80000 in a molten state. The larger the molecular weight of the aliphatic polycarbonate diol, the higher the block property retention and the block property. The polycarbonate diol has a number average molecular weight of preferably 5000 or more, more preferably 7000 or more, and still more preferably 10,000 or more. The upper limit of the molecular weight of the polycarbonate diol is preferably 80000 or less, more preferably 70000 or less, and even more preferably 60000 or less, from the viewpoint of compatibility between the hard segment and the soft segment. If the molecular weight of the polycarbonate diol is too large, the compatibility is lowered, phase separation occurs, the mechanical properties are greatly affected, and the strength and elongation are lowered.
The tensile strength at the time of the cutting | disconnection of the thermoplastic polyester elastomer used for the heat resistant corrugated tube of this invention is 15-100 Mpa, Preferably it is 20-60 Mpa.

  Moreover, it is preferable that the thermoplastic polyester elastomer used for the heat resistant corrugated tube of the present invention has a flexural modulus of 1000 MPa or less. The flexural modulus is more preferably 800 MPa or less, and further preferably 600 MPa or less. When the flexural modulus exceeds 1000 MPa, the flexibility of the thermoplastic polyester elastomer is insufficient, which is not preferable. The lower limit is preferably 50 MPa or more, more preferably 80 MPa or more, and further preferably 100 MPa or more. If the pressure is less than 50 MPa, the thermoplastic polyester elastomer is too soft to ensure the strength of the product.

  Further, the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention has an elongation at break after the heat aging test and the water aging test of the thermoplastic polyester elastomer composition evaluated by the method described in the measurement method section. The retention is preferably 50% or more.

  The aromatic polyester suitable as the polyester constituting the hard segment in the thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention preferably has a number average molecular weight of 10,000 to 40,000.

  The method for optimizing the molecular weight of the polycarbonate diol is not limited. An optimal molecular weight may be purchased or prepared, or a molecular weight adjusted by increasing the molecular weight in advance with a low molecular weight polycarbonate diol and a chain extender such as diphenyl carbonate or diisocyanate may be used. .

  For example, as a method for producing the above high molecular weight aliphatic polycarbonate diol, the above aliphatic diol and the following carbonates, that is, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, diisopropyl carbonate, dibutyl carbonate, dimethyl carbonate, diphenyl carbonate It can obtain by making it react.

  Another method for producing a high molecular weight aliphatic polycarbonate diol is to react a low molecular weight aliphatic polycarbonate diol with dimethyl carbonate, diethyl carbonate, dipropyl carbonate, diisopropyl carbonate, dibutyl carbonate, dimethyl carbonate, diphenyl carbonate, etc. This is also possible.

  The thermoplastic polyester elastomer used in the heat-resistant corrugated tube of the present invention is molded from a melt by a usual molding technique such as injection molding, flat film extrusion, extrusion blow molding, or coextrusion.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but is not limited thereto. In this specification, each measurement was performed according to the following method.
(1) Reduced viscosity of thermoplastic polyester elastomer 0.05 g of thermoplastic polyester elastomer was dissolved in 25 mL of a mixed solvent (phenol / tetrachloroethane = 60/40) and measured at 30 ° C. using an Ostwald viscometer.

(2) Melting point (Tm) of thermoplastic polyester elastomer
Thermoplastic polyester elastomer dried under reduced pressure at 50 ° C. for 15 hours was measured by using a differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation) at a rate of 20 ° C./min from the room temperature. did.
In addition, 10 mg of a measurement sample was weighed in an aluminum pan (TA Instruments, product number 900793.901), sealed with an aluminum lid (TA Instruments, product number 900794.901), and measured in an argon atmosphere. .

(3) Tensile strength and elongation at the time of cutting of the thermoplastic polyester elastomer The tensile strength and elongation at the time of cutting of the thermoplastic polyester elastomer were measured in accordance with JIS K 6251. The test piece was injection-molded into a 100 mm × 100 mm × 2 mm flat plate at a cylinder temperature (Tm + 20 ° C.) and a mold temperature of 30 ° C. using an injection molding machine (model-SAV, manufactured by Yamashiro Seiki Co., Ltd.), and then a dumbbell shape. A No. 3 test piece was punched from a flat plate.

(4) Flexural modulus Measured according to ASTM D790.

(5) Heat aging resistance (Elongation retention at cutting after heat aging test)
<Preparation of test piece>
A polyfunctional epoxy compound (0.35 parts by mass), a catalyst (0.2 parts by mass) and a stabilizer (1.2 parts by mass) are placed in a drum tumbler at 100 parts by mass of a thermoplastic polyester elastomer pellet dried at 100 ° C. for 8 hours under reduced pressure. For 30 minutes. The mixture was melt-kneaded at a temperature of (Tm + 20 ° C.) using a 40 mmφ same-direction twin screw extruder with a vent hole and extruded into a strand shape, and the strand was cut into chips by cooling with water. The chip was dried under reduced pressure at 100 ° C. to obtain a chip of a thermoplastic polyester elastomer composition.
The thermoplastic polyester elastomer was injection molded into a 100 mm × 100 mm × 2 mm flat plate at a cylinder temperature (Tm + 20 ° C.) and a mold temperature of 30 ° C. using an injection molding machine (model-SAV manufactured by Yamashiro Seiki Co., Ltd.) A dumbbell-shaped No. 3 test piece was punched from the flat plate.
<Evaluation of elongation retention during dry heat treatment and cutting>
The test piece obtained by the above method was treated at 180 ° C. for 1000 hours in a gear-type hot air dryer, and then elongation at break was measured according to JIS K 6251. For the test pieces not subjected to the dry heat treatment, the elongation at break was measured by the same method, and the retention rate of the elongation at break after the dry heat treatment was calculated.

(6) Water aging resistance (Elongation retention at cutting after water aging test)
<Preparation of test piece>
It was produced by the same method as described in the above heat aging resistance measurement method.
<Evaluation of boiling water treatment, elongation retention during cutting>
After the test piece was treated in boiling water at 100 ° C. for 2 weeks, the elongation at break was measured according to JIS K 6251. For the test pieces not treated in boiling water, the elongation at break was measured in the same manner, and the retention of elongation at break after the boiling water treatment was calculated.

(7) Average chain length and block property of hard segment and soft segment (when the glycol component of the polyester is butanediol and the glycol in the aliphatic polycarbonate diol is an aliphatic diol having 5 to 12 carbon atoms)
[NMR measurement]
Apparatus: Fourier transform nuclear magnetic resonance apparatus (AVANCE500 manufactured by BRUKER)
Measuring solvent: Deuterated chloroform Sample solution concentration: 3-5 vol%
¹ H resonance frequency: 500.13 MHz
Detection pulse flip angle: 45 °
Data acquisition time: 4 seconds Delay time: 1 second Integration count: 50-200 times Measurement temperature: Room temperature

〔Method of calculation〕
The H-NMR integrated value (in arbitrary units) of the methylene peak adjacent to oxygen in the aromatic dicarboxylic acid-butanediol-butanediol of the aromatic dicarboxylic acid chain is defined as A.
The H-NMR integrated value (unit is arbitrary) of the peak of the methylene adjacent to oxygen closer to carbonic acid of butanediol of the aromatic dicarboxylic acid-butanediol-carbonic acid chain is defined as C.
H-NMR integrated value (unit is arbitrary) of the peak of methylene adjacent to oxygen closer to the aromatic dicarboxylic acid of aromatic dicarboxylic acid-C5-C12 aliphatic diol-carbonic acid chain hexanediol And
The H-NMR integrated value (unit is arbitrary) of the methylene peak adjacent to oxygen of the carbonic acid-aliphatic diol having 5 to 12 carbon atoms-aliphatic diol having 5 to 12 carbon atoms in the carbonic acid chain is defined as D.
Hard segment average chain length (x) is
x = ((((A / 4) + (C / 2)) / ((B / 2) + (C / 2)))) × 2.
Soft segment average chain length (y) is
y = (((D / 4) + (B / 2)) / ((B / 2) + (C / 2)))) × 2.
The block property (B) was calculated by the following equation (1) from the values of x and y obtained by the above method. The smaller the value of B, the higher the block property.
B = 1 / x + 1 / y (1)

(8) Blockability retention 10 mg of the thermoplastic polyester elastomer dried under reduced pressure at 50 ° C. for 15 hours is weighed in an aluminum pan (TA Instruments, product number 900793.901), and an aluminum lid (TA Instruments, product number). After preparing the measurement sample in a sealed state in 90079.901), a differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation) was used, and the temperature was increased from room temperature to 300 ° C. at a temperature rising rate of 20 ° C./min under a nitrogen atmosphere. The sample was taken out of the sample pan, held at 300 ° C. for 3 minutes, and immersed in liquid nitrogen to be rapidly cooled. Thereafter, the sample was taken out from the liquid nitrogen and left at room temperature for 30 minutes. The measurement sample pan is set on a differential scanning calorimeter and allowed to stand at room temperature for 30 minutes, and then the temperature is raised again from room temperature to 300 ° C. at a temperature rising rate of 20 ° C./min. The melting point difference (Tm1−Tm3) between the melting point (Tm1) obtained by the first measurement when this cycle is repeated three times and the melting point (Tm3) obtained by the third measurement is obtained, and the melting point difference is determined as a block property. Retainability. The smaller the temperature difference, the better the blockability retention.
Based on the melting point difference evaluated by the above method, the blockability retention was determined and displayed according to the following criteria.
A: Melting point difference 0 to 30 ° C.
○: Melting point difference 30-40 ° C
(Triangle | delta): Melting | fusing point difference 40-50 degreeC
X: Melting point difference 50 ° C. or more

(9) Molecular weight of aliphatic polycarbonate diol An aliphatic polycarbonate diol sample was dissolved in deuterated chloroform (CDCl ₃ ), and the end group was determined by measuring H-NMR in the same manner as described in (7) above. It calculated and calculated | required with the following formula.
Molecular weight = 1000000 / ((Terminal group weight (equivalent / ton)) / 2)
(10) Number average molecular weight (Mn) of aromatic polyester
The value was calculated according to the following formula using the value of reduced viscosity (ηsp / c) determined by the same method as that for measuring the reduced viscosity of the thermoplastic polyester elastomer.
ηsp / c = 1.919 × 10 ⁻⁴ × Mn ^0.8929 −0.0167

(A) Molding of corrugated tube 0.35 parts by mass of polyfunctional epoxy compound, 0.2 parts by mass of catalyst, 1.2 parts by mass of stabilizer on 100 parts by mass of pellets of thermoplastic polyester elastomer dried under reduced pressure at 100 ° C for 8 hours Was placed in a drum tumbler and mixed for 30 minutes at room temperature. The mixture was melt-kneaded at a temperature of (Tm + 20 ° C.) using a 40 mmφ same-direction twin screw extruder with a vent hole and extruded into a strand shape, and the strand was cut into chips by cooling with water. The chip was dried under reduced pressure at 100 ° C. to obtain a chip of a thermoplastic polyester elastomer composition.
A corrugated tube (25 mmφ) was formed by a profile extrusion molding machine in which the chips of the obtained thermoplastic polyester elastomer composition were heated to 240 ° C.

(B) Heat resistance test of corrugated tube The 30 cm long corrugated tube obtained by the above method was treated in a gear type hot air dryer at 180 ° C. for 1000 hours, and then a ring with an inner diameter of 3 cm was made with the corrugated tube. The state of cracking was observed, and the flexibility of the molded product was evaluated in three stages.
◎: Easy to bend without cracking ○: Slightly difficult to bend but without cracking ×: With cracking

(C) Corrugated tube water resistance test After the corrugated tube 30 cm long obtained by the above method was treated in boiling water at 100 ° C. for 2 weeks, a ring with an inner diameter of 3 cm was made with the corrugated tube, and the corrugated tube surface was cracked. And the flexibility of the molded product was evaluated in three stages.
◎: Easy to bend without cracking ○: Slightly difficult to bend but without cracking ×: With cracking

[Method for producing aliphatic polycarbonate diol]
Method for producing aliphatic polycarbonate diol (molecular weight 10,000):
Aliphatic polycarbonate diol (Ube Industries, Ltd. carbonate diol UH-CARB200, molecular weight 2000, 1,6-hexanediol type) 100 parts by mass and diphenyl carbonate 8.6 parts by mass were respectively charged and reacted at a temperature of 205 ° C. and 130 Pa. It was. After 2 hours, the contents were cooled and the polymer was removed. The molecular weight was 10,000.

Method for producing aliphatic polycarbonate diol (molecular weight 20000):
Aliphatic polycarbonate diol (Ube Industries, Ltd. carbonate diol UH-CARB200, molecular weight 2000, 1,6-hexanediol type) 100 parts by mass and diphenyl carbonate 9.6 parts by mass were respectively charged and reacted at a temperature of 205 ° C. and 130 Pa. It was. After 2 hours, the contents were cooled and the polymer was removed. The molecular weight was 20000.

Method for producing aliphatic copolymer polycarbonate diol (molecular weight 10,000):
Aliphatic copolymer polycarbonate diol (Asahi Kasei Chemicals carbonate diol T5652, molecular weight 2000, copolymer of 1,6-hexanediol and 1,5-pentanediol, amorphous) 100 parts by mass and diphenyl carbonate 8.6 Each mass part was charged and reacted at a temperature of 205 ° C. and 130 Pa. After 2 hours, the contents were cooled and the polymer was removed. The molecular weight was 10,000.

Production method of aliphatic polycarbonate diol (molecular weight 85000) Aliphatic polycarbonate diol (Ube Industries, Ltd. carbonate diol UH-CARB200, molecular weight 2000, 1,6-hexanediol type) and diphenyl carbonate were each 100 parts by mass and 10.7. Polymerization was advanced at a temperature of 205 ° C. and 130 Pa by charging a mass part. After 2 hours and 45 minutes, the contents were cooled and the polymer was removed. The molecular weight was 85000.

[Example 1]
100 parts by mass of polybutylene terephthalate (PBT) having a number average molecular weight of 30000 and 43 parts by mass of a polycarbonate diol having a number average molecular weight of 10,000 prepared by the above method are stirred at 230 ° C. to 245 ° C. under 130 Pa for 1 hour, After confirming that it became transparent, the contents were taken out and cooled to obtain a polymer. Each physical property of the obtained polymer was measured, and the result is shown in Table 1. The corrugated tube molded using the polymer (thermoplastic polyester elastomer) obtained in this example had good evaluation results, and was a high-quality corrugated tube excellent in heat resistance and water resistance.

[Example 2]
100 parts by weight of polybutylene terephthalate (PBT) having a number average molecular weight of 30000 and 43 parts by weight of a polycarbonate diol having a number average molecular weight of 20000 prepared by the above method were stirred at 230 ° C. to 245 ° C. under 130 Pa for 1.5 hours, After confirming that the resin became transparent, the contents were taken out and cooled to obtain a polymer. The corrugated tube molded using the obtained polymer had good evaluation results and was a high-quality corrugated tube excellent in heat resistance and water resistance.

Example 3
100 parts by mass of polybutylene terephthalate (PBT) having a number average molecular weight of 30,000 and 43 parts by mass of an aliphatic copolymer polycarbonate diol having a number average molecular weight of 10,000 prepared by the above method are stirred at 230 ° C. to 245 ° C. under 130 Pa for 1 hour. After confirming that the resin became transparent, the contents were taken out and cooled to obtain a polymer. The corrugated tube molded using the obtained polymer had good evaluation results and was a high-quality corrugated tube excellent in heat resistance and water resistance. Further, the resin has excellent low-temperature characteristics as compared with the case where a polycarbonate diol composed of 1,6-hexanediol is used as the soft segment.

Example 4
100 parts by weight of polybutylene naphthalate (PBN) having a number average molecular weight of 30,000 and 43 parts by weight of a polycarbonate diol having a number average molecular weight of 10,000 prepared by the above method are stirred at 245 ° C. to 260 ° C. under 130 Pa for 1 hour, and resin Was confirmed to be transparent, and the contents were taken out and cooled to obtain a polymer. The physical properties of the obtained polymer were measured, and the results are shown in Table 1. The polymer (thermoplastic polyester elastomer) obtained in this example was a block equivalent to the thermoplastic polyester elastomer obtained in Example 1. The thermoplastic polyester elastomer obtained in Example 1 had a higher melting point and higher quality than the thermoplastic polyester elastomer obtained in Example 1.

[Comparative Example 1]
100 parts by mass of polybutylene terephthalate (PBT) having a number average molecular weight of 30000 and 43 parts by mass of polycarbonate diol C (carbonate diol UH-CARB200, molecular weight 2000) manufactured by Ube Industries, Ltd. are stirred at 230 ° C. to 245 ° C. and 130 Pa for 10 minutes. After confirming that the resin became transparent, the contents were taken out and cooled to obtain a polymer. Each physical property of the obtained polymer was measured, and the result is shown in Table 1. The polymer (thermoplastic polyester elastomer) obtained in this comparative example was inferior in block property and block property retention. Furthermore, the reduced viscosity was low, the heat aging resistance was inferior, and the quality was low. Moreover, since the molecular weight was low, the flexural modulus could not be measured.

[Comparative Example 2]
100 parts by weight of polybutylene terephthalate (PBT) having a number average molecular weight of 30000 and 43 parts by weight of a polycarbonate diol having a number average molecular weight of 85000 prepared by the above method were stirred at 230 ° C. to 245 ° C. under 130 Pa for 5 hours. Remained cloudy. The contents were taken out and cooled to obtain a polymer. Each physical property of the obtained polymer was measured and shown in result 1. The polymer (thermoplastic polyester elastomer) obtained in this comparative example has excellent blockability and blockability retention, but the compatibility between the hard segment and the soft segment is poor, so mechanical properties such as tensile strength are inferior. The characteristic variation was large and the quality was low.

[Comparative Example 3]
100 parts by weight of polybutylene terephthalate (PBT) having a number average molecular weight of 2000 and aliphatic copolymer polycarbonate diol (carbonate diol T5652 manufactured by Asahi Kasei Chemicals Co., Ltd., molecular weight 2000, 1,6-hexanediol and 1,5-pentanediol Polymer, amorphous) and 43 parts by mass were stirred at 230 ° C. to 245 ° C. and 130 Pa for 10 minutes to confirm that the resin became transparent, and the contents were taken out and cooled to obtain a polymer. Each physical property of the obtained polymer was measured, and the result is shown in Table 1. The polymer (thermoplastic polyester elastomer) obtained in this comparative example was inferior in blockability and blockability retention and was of lower quality than the thermoplastic polyester elastomer obtained in Example 4. Moreover, since the molecular weight was low, the flexural modulus could not be measured.

[Comparative Example 4]
Regarding the thermoplastic polyester elastomer (polybutylene terephthalate unit / polyoxytetramethylene glycol unit = 63.5 / 36.5 (mass ratio)) composed of polybutylene terephthalate and polyoxytetramethylene glycol, the physical properties were measured and the results As shown in Table 1, it is clear that the heat aging resistance is inferior.

[Comparative Example 5]
Various properties of a thermoplastic polyester elastomer (polybutylene terephthalate unit / polycaprolactone unit = 70/30 (mass ratio)) composed of polybutylene terephthalate and polycaprolactone were measured and the results are shown in Table 1, but the water resistance is poor. It is clear. Further, a slight odor was felt when remelted.

  As mentioned above, although the thermoplastic thermoplastic polyester elastomer of this invention was demonstrated based on several Example, this invention is not limited to the structure described in the said Example, The structure described in each Example is shown. The configuration can be changed as appropriate within a range not departing from the spirit of the invention, such as appropriate combination.

  The heat-resistant corrugated tube of the present invention has the characteristics of a polyester polycarbonate type elastomer that has good heat resistance and is excellent in heat aging resistance, water resistance, low temperature characteristics, and the like. Moreover, since recyclability is improved, it can lead to environmental load and cost reduction. Therefore, since it has such excellent characteristics and advantages, it is useful for applications such as automobiles and home appliance parts that require heat aging resistance, water resistance, and low temperature characteristics. In particular, it can be suitably used for corrugated tubes used around automobile engines that require a high degree of heat resistance, which greatly contributes to the industry.

Claims (5)

  A polyester elastomer in which a hard segment composed of a polyester composed of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol and a soft segment composed mainly of an aliphatic polycarbonate are bonded, and the differential scanning of the thermoplastic polyester elastomer Using a calorimeter, when the temperature was raised from room temperature to 300 ° C. at a temperature rising rate of 20 ° C./min, held at 300 ° C. for 3 minutes, and then the temperature was lowered to room temperature at a temperature lowering rate of 100 ° C./min three times The melting point difference (Tm1−Tm3) between the melting point (Tm1) obtained by the first measurement and the melting point (Tm3) obtained by the third measurement is 0 to 50 ° C., and the tensile strength at the time of cutting is 15 to 100 MPa. A thermoplastic polyester elastomer is used for at least one of the tube components. Le gate tube. When the average chain length (x) of the hard segment and the average chain length (y) of the soft segment calculated using the nuclear magnetic resonance method (NMR method) are used, the average chain length (x) of the hard segment is 5 to 20 And the block property (B) calculated by the following formula (1) is 0.11 to 0.45, wherein the thermoplastic polyester elastomer according to claim 1 is used for at least one of the tube components. Corrugated tube.
B = 1 / x + 1 / y (1)   2. The thermoplastic polyester elastomer according to claim 1, wherein the hard segment comprises a polybutylene terephthalate unit, and the melting point of the obtained thermoplastic polyester elastomer is 200 to 225 ° C. The thermoplastic polyester elastomer according to claim 1 is used for at least one of the tube components. Corrugated tube.   The thermoplastic polyester elastomer according to claim 1, wherein the hard segment comprises polybutylene naphthalate units, and the thermoplastic polyester elastomer obtained has a melting point of 215 to 240 ° C. Corrugated tube characterized by being used for   The polyester comprising an aromatic dicarboxylic acid and an aliphatic or alicyclic diol and an aliphatic polycarbonate diol having a molecular weight of 5000 to 80000 are produced by reacting in a molten state. A corrugated tube using at least one of the thermoplastic polyester elastomers in at least one of the tube components.