JP4053837B2 - Catalyst for producing polyester and method for producing polyester using the same - Google Patents

Description

【００５２】
＜溶融重縮合＞
実施例４
反応容器内で、テレフタル酸とエチレングリコールを原料として、直接エステル化法により製造したエチレンテレフタレート低重合体１０４ｇを２６０℃で融解させ、これに実施例１で製造した触媒のエチレングリコール溶液を、溶融重縮合終了時のポリエステル樹脂理論収量に対しチタン原子として１００ｐｐｍとなるよう添加した。次いで融解液を攪拌翼により攪拌しながら、８０分間で２８０℃まで段階的に昇温するとともに、反応系の圧力を６０分間で常圧から１．３×１０²Ｐａまで段階的に下げ、温度２８０℃，圧力１．３×１０²Ｐａに到達した後は、温度、圧力を一定に保った。
減圧開始１１１分後、攪拌を止め、反応系内に窒素ガスを導入することにより重合を停止した。その後ポリマーを反応容器より抜き出し、水冷却することにより、ストランド状のポリマーを得た。これをカットすることによりペレット状にした。減圧開始から重合停止までの時間（重合時間）、得られたポリマーの固有粘度および酸価（ＡＶ）値の測定結果を下記表２に示す。
【００５３】
実施例５
実施例４において、実施例１に記載の触媒を使用した代わりに、実施例２で製造した触媒のエチレングリコール溶液を、溶融重縮合終了時のポリエステル樹脂理論収量に対しチタン原子として２２ｐｐｍとなるよう添加し、減圧開始１１８分後に重合を停止した以外は実施例４と同様に行った。得られたポリマーの固有粘度および酸価（ＡＶ）値の測定結果を表２に示す。
【００５４】
実施例６
実施例４において、実施例１に記載の触媒を使用した代わりに、実施例３で製造した触媒のエチレングリコール溶液を、溶融重縮合終了時のポリエステル樹脂理論収量に対しチタン原子として９２ｐｐｍとなるよう添加し、減圧開始１１１分後に重合を停止した以外は実施例４と同様に行った。得られたポリマーの固有粘度および酸価（ＡＶ）値の測定結果を表２に示す。
【００５５】
比較例３
実施例４において、実施例１に記載の触媒を使用した代わりに、比較例１で製造した触媒のエチレングリコール溶液を、溶融重縮合終了時のポリエステル樹脂理論収量に対しチタン原子として１００ｐｐｍとなるよう添加し、減圧開始１４７分後に重合を停止した以外は実施例１と同様に行った。得られたポリマーの固有粘度および酸価（ＡＶ）値の測定結果を表２に示す。
【００５６】
比較例４
実施例４において、実施例１に記載の触媒を使用した代わりに、比較例２で製造した触媒のエチレングリコール溶液を、溶融重縮合終了時のポリエステル樹脂理論収量に対しチタンとして４ｐｐｍとなるよう添加し、減圧開始１５８分後に重合を停止した以外は実施例１と同様に行った。得られたポリマーの固有粘度および酸価（ＡＶ）値の測定結果を表２に示す。
【００５７】
【表２】

比較例３ Ｓｉを複合していないので活性低い。
比較例４ 平均電気陰性度が＜９なので、ポリマーの熱安定性が悪い。
【００５８】
【発明の効果】
本発明によれば、適切なルイス酸性元素と適切なルイス塩基性元素とを組み合わせることにより、好ましいルイス酸塩基性に制御された活性成分が、ケイ素により高分散された、活性の高いポリエステル製造用触媒を提供することが出来、しかもこの触媒を使用することにより優れた特性を有するポリエステルを生産性良好に製造することができるので、本発明の工業的価値は高い。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a catalyst for producing a polyester and a method for producing a polyester using the catalyst. Specifically, in addition to a combination of an appropriate Lewis acidic element and an appropriate Lewis basic element as an essential catalyst component, a catalyst for producing a polyester having a high activity and excellent quality, comprising a silicon component, and The present invention relates to a method for producing a polyester having excellent characteristics by using this catalyst with good productivity.
[0002]
[Prior art]
Conventionally, polyesters typified by polyethylene terephthalate have excellent mechanical strength, chemical stability, gas barrier properties, hygiene, etc., and are relatively inexpensive and lightweight, so various packaging materials such as bottles and films Or it has been widely used as a fiber.
These polyesters are usually produced by polycondensation of aromatic dicarboxylic acids such as terephthalic acid and glycols such as ethylene glycol. Conventionally, antimony compounds are mainly used as polycondensation catalysts. Yes. However, when the polyester produced using such a catalyst is molded and used as a food or drink container, for example, the antimony remaining in the polyester resin elutes from the container at a high temperature and is slightly contained in the food or drink. There are concerns about such problems as migration, and polyester resins have been strongly desired instead.
[0003]
On the other hand, many methods using a titanium compound as a polycondensation catalyst have been proposed as a method for producing a polyester resin containing no antimony compound.
As titanium compounds used as the polycondensation catalyst, for example, the following titanium compounds have been proposed.
In JP-T-2002-503274, it is produced by precipitation by simultaneous hydrolysis of a titanium compound and a metal compound of a metal selected from the group of IA, IIA, VIIIA, IB, IIB, IIIB and IVB. Coprecipitates have been shown to be used alone or as mixtures as catalysts.
[0004]
Japanese Patent Laid-Open No. 2001-064378 discloses hydrolysis obtained by hydrolyzing a mixture of a titanium halide and a compound of at least one element selected from elements other than titanium or a precursor of this compound. It has been shown that a solid titanium-containing compound obtained by dehydrating and drying a product is used as a catalyst.
However, according to the study by the present inventor, the method using a catalyst comprising these titanium compounds has a disadvantage that the time required for the polycondensation reaction is long, and the obtained polyester resin has a thermal stability represented by an acid value and the like. Due to the problem of lack of properties, it has been found that the industrial production method is still unsatisfactory. Therefore, there is a strong desire for an alternative catalyst that can produce even better activity and high quality polyester.
[0005]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and has the disadvantage that it takes a long time for the polycondensation reaction caused by the conventional catalyst, and the problem that the resulting polyester resin lacks thermal stability and is inferior in quality. The present invention provides a polyester production catalyst that can be eliminated, and further provides a method for producing a polyester having excellent characteristics with good productivity by using such a catalyst.
[0006]
[Means for Solving the Problems]
As a result of intensive studies in view of the above problems, the present inventors have appropriately combined the Lewis acidic element atom and the Lewis basic element atom, and determined the average electronegativity of the electronegativity of each atom ion within a specific range. The catalyst in which these atoms are highly dispersed by using silicon atoms together is highly active as a polyester production catalyst, and the polyester resin produced using this catalyst has extremely high quality. It has been found that it is excellent, and the present invention has been completed.
[0007]
      That is, the gist of the present invention is a polyester production catalyst containing at least one atom selected from a silicon atom, a Lewis acidic element, and at least one atom selected from a Lewis basic element, and comprising a Lewis acidic catalyst. An average electronegativity calculated from the electronegativity of each atomic ion of an atom selected from an element and an atom selected from a Lewis basic element is 9 to 15, and a silicon compound or Lewis acid element as an alkoxideFrom the group consisting of titanium, zirconium, hafnium, iron, cobalt, aluminum, gallium and tinAs a compound of at least one element selected and a Lewis basic elementFrom the group consisting of sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, zinc and ceriumA polyester production catalyst obtained by using a hydrolyzate of each or a mixture of at least one elemental compound selected, and an aromatic dicarboxylic acid characterized by using the polyester production catalyst Or it exists in the manufacturing method of polyester which consists of polycondensing the dicarboxylic acid component and diol component which have the ester-forming derivative as a main component through esterification reaction or transesterification reaction.
[0009]
  The present inventionAs a preferable aspect of, LeThe chair acidic element compound and the Lewis basic element compound are compounds selected from the group consisting of hydroxide, nitrate, halide, carbonate, carboxylate, alkoxide, and acetylacetonate, respectively.Is an alkoxideIt is a product obtained by hydrolyzing a silicon compound, a Lewis acidic element compound and a Lewis basic element compound in the presence of coexistence, and the electronegativity of atomic ions of the Lewis acidic element is greater than 10, A negative degree is 10 or less.
[0010]
      In a more preferred embodiment, Lewis acidic elementsIsElement selected from the group consisting of titanium, zirconium, hafnium, iron, cobalt, aluminum, gallium and tinBut, Preferably titanium, Lewis basic elementIsElement selected from the group consisting of sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, zinc and ceriumButAlso preferred is magnesium or zinc.
[0011]
Moreover, it is also mentioned as a suitable aspect that the ratio (atomic ratio) of the total amount of the Lewis acidic element and the Lewis basic element to the silicon element is 80:20 to 5:95.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the present invention will be described in detail.
  The polyester production catalyst according to the present invention must contain at least one atom selected from at least silicon atoms, Lewis acidic elements, and at least one atom selected from Lewis basic elements. The average electronegativity calculated from the electronegativity of each atomic ion of an atom selected from an acidic element and an atom selected from a Lewis basic element needs to be controlled in the range of 9 to 15,Obtained by using a hydrolyzate of each or a mixture of a silicon compound that is an alkoxide, a compound of at least one element selected as a Lewis acidic element, and a compound of at least one element selected as a Lewis basic elementIs.
[0013]
In the present invention, the element selected as the Lewis acidic element is an element that acts as a Lewis acid during the polymerization of the polyester, and the element selected as the Lewis basic element is an element that functions as a Lewis base.
Here, as an index for selecting an element selected as the Lewis acidic element and an element selected as the Lewis basic element, the electronegativity of the atomic ion of the element can be used. Electronegativity of atomic ions of elements is described in Junichi Tanaka, Catalyst Engineering Course, Vol. 10, Chapter 28, Section 1, Section 5, Section 752, Jinshokan Tokyo (published on September 20, 1974, reprinted third edition) The value obtained by the described method is used.
[0014]
In the catalyst of the present invention, the average electronegativity calculated from the electronegativity of the atomic ions of the elements selected as the Lewis acidic element and the Lewis basic element as described above must be within the predetermined range. It is. For this purpose, it is more preferable to select a combination of elements that increases the difference in electronegativity between atomic ions of the element selected as the Lewis acidic element and the element selected as the Lewis basic element.
[0015]
Specifically, the electronegativity of atomic ions of at least one element selected as a Lewis acidic element is greater than 10, and the electronegativity of atomic ions of at least one element selected as a Lewis basic element is All are preferably 10 or less, and further, the electronegativity of atomic ions of at least one element selected as a Lewis acidic element is greater than 10 and 14 or less, and at least one element selected as a Lewis basic element It is preferable that the electronegativity of atomic ions of these elements is 2 or more and 10 or less.
By selecting the electronegativity of each atomic ion of Lewis acidic element and Lewis basic element in such a combination, the difference in electronegativity of both atomic ions due to the larger and smaller atoms is moderate. It is presumed that the acid-basicity of the catalyst produced by the combination becomes easier to control.
[0016]
As a more preferable combination, at least one element selected as a Lewis acidic element is any of Group 4, 8, 13, and 14 elements, and at least one element selected as a Lewis basic element is It may be any one of Group 1, Group 2, Group 3, Group 12, Group 15, and a lanthanoid element.
More specifically, at least one element selected as a Lewis acidic element is any of titanium, zirconium, hafnium, iron, cobalt, aluminum, gallium, and tin, and at least one element selected as a Lewis basic element Is preferably any of sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, zinc and cerium. More preferably, one of the elements selected as the Lewis acidic element is titanium, and one of the elements selected as the Lewis basic element is magnesium or zinc.
[0017]
The value of the average electronegativity is related to the Lewis acid basicity (strong acidity is one index) of the catalyst that is generated by combining elements (not necessarily the Lewis acid basicity of the original element). Controlling the electronegativity is controlling the Lewis acid basicity of the catalyst.
The relationship between the average value of the electronegativity of the ions of each element of the binary oxide and the highest value of the acid strength measured by the method using an indicator is K. Shibata, T. Kiyoura, J. Kitagawa, T Sumiyoshi, K. Tanabe, Bull. Chem. Soc. Japan, 46, 2985 (1973), which makes it possible to predict the acid strength of complex oxides from the electronegativity of elemental ions. is there.
[0018]
In the present invention, the average electronegativity calculated from the electronegativity of the atomic ion of the element selected as the Lewis acidic element and the electronegativity of the atomic ion of the element selected as the Lewis basic element as described above is in a desired range. That is, it is necessary to select each element in combination so as to be controlled within the range of 9 to 15, whereby the catalyst becomes preferable Lewis acid basic, and by using this, polyester having good thermal stability. It becomes a catalyst that can be produced.
[0019]
In the present invention, the average electronegativity can be determined as follows. For example, when the atomic ratio of silicon (Si), an element selected as a Lewis acidic element (LA), and an element selected as a Lewis basic element (LB) in the catalyst is the formula (1), the average electronegativity is (2 ) Equation.
(1) Formula: Si: LA: LB = a: b: c (atomic ratio)
(2) Formula: Average electronegativity (X_AVE)
X_AVE= [(X_LAXb) + (X_LB× c)] / (b + c)
(X in the formula_LA, X_LBIndicates the electronegativity of the atomic ion of the element selected as the Lewis acidic element and the electronegativity of the atomic ion of the element selected as the Lewis basic element. )
[0020]
Further, when n elements selected as Lewis acidic elements and m elements selected as Lewis basic elements are selected, similarly, silicon (Si), elements selected as Lewis acidic elements (LA1, LA2,... , LAn) and the atomic ratio of elements selected as Lewis basic elements (LB1, LB2,..., LBm) are represented by the formula (3), the average electronegativity can be calculated using the formula (4). .
(3) Formula: Si: LA1: LA2: ...: LAn: LB1: LB2: ...: LBm
= A: b₁: B₂: ...: b_n: C₁: C₂: ...: c_m(Atomic ratio)
(4) Formula: Average electronegativity (X_AVE)
X_AVE= [{(X_LA1Xb₁) + (X_LA1Xb₂) + ... + (X_LAnXb_n)} + {(X_LB1× c₁) + (X_LB1× c₂) + ... + (X_LBn× c_m)}] / [(B₁+ B₂+ ... + b_n) + (C₁c₂+ ... + c_m]]
(X in the formula_LA1, X_LA2And X_LAnIndicates the electronegativity of each atomic ion of the element selected as the Lewis acidic element,_LB1, X_LB2And X_LBmIndicates the electronegativity of each atomic ion of the element selected as the Lewis basic element. )
[0021]
In this invention, the average electronegativity calculated | required from the electronegativity of the atomic ion of the element chosen as a Lewis acidic element and the element chosen as a Lewis basic element is 9-15. More preferably, it is 10-13, More preferably, it is 10-12.
If the average electronegativity is less than 9, the Lewis basicity of the catalyst becomes strong, and if it exceeds 15, the Lewis acidity of the catalyst becomes strong, and the thermal stability of the polyester produced using the catalyst tends to deteriorate. Is not preferable.
That is, according to the present invention, by combining an appropriate Lewis acidic element and an appropriate Lewis basic element, a catalyst controlled to a preferable Lewis acid basic can be obtained, and by using this, thermal stability is good. Polyester can be produced.
[0022]
Furthermore, in this invention, it can be set as the catalyst excellent in the polymerization activity by using silicon together with the active ingredient of said Lewis acidic element and Lewis basic element. This is achieved by appropriately dispersing an active ingredient controlled to a preferable Lewis acid basicity, which is a combination of an appropriate Lewis acidic element and an appropriate Lewis basic element, with silicon.
If the amount of the silicon compound used is too large, the catalyst activity may be lowered. If the amount is too small, the active component is not sufficiently dispersed, which is not preferable. Usually, the ratio (atomic ratio) of the total amount of Lewis acidic element and Lewis basic element to silicon element is 80:20 to 5:95, preferably 60:40 to 5:95.
[0024]
  For catalyst preparationThe leAs the compound of the chair acid element and the Lewis basic element, any compound may be used as long as the counter ions of these elements do not adversely affect the polycondensation reaction. Specifically, hydroxide, nitrate, halide, carbonate Salts, carboxylates, alkoxides, acetylacetonates and the like can be used. Of these, carboxylate and alkoxide are preferable.
  As the solvent, water or an organic solvent can be used. In particular, aliphatic diols which are also raw materials for polyester are preferable, and ethylene glycol is most preferable.
[0025]
In addition, the polyester production catalyst of the present invention can be obtained as a hydrolyzate of a compound of an element selected as a Lewis acidic element, a compound of an element selected as a Lewis basic element, and a silicon compound or a mixture thereof. . Here, the mixture includes a mixture of a Lewis acidic element compound, a Lewis basic element compound, and a silicon compound, a mixture of a plurality of Lewis acidic element compounds, and a mixture of a plurality of Lewis basic element compounds. Specifically, the Lewis acidic element compound, the Lewis basic element compound and the silicon compound are individually or as a mixture to form a solution or suspension, and if necessary, a pH adjuster is added to perform hydrolysis. It is preferable to obtain as a produced precipitate or a coprecipitate. As a solvent used for preparing the solution and suspension, an organic solvent such as water or ethanol can be used, and water is particularly preferable.
[0026]
In the present invention, the Lewis acidic element compound, Lewis basic element compound and silicon compound to be hydrolyzed are preferably water-soluble compounds, but need not be particularly water-soluble as long as they have good dispersibility in commonly used solvents. Specifically, hydroxides, nitrates, halides, carbonates, carboxylates, alkoxides, acetylacetonates, and the like of these elements can be used. Of these, preferred are halides and alkoxides.
The form of the catalyst obtained by hydrolysis differs depending on the type of compound and hydrolysis conditions, and is not necessarily clear, but is presumed to be a form of a hydroxide containing an oxide. Although the hydrolysis temperature depends on the type of the compound, if it is too high, it is difficult to control the hydrolysis rate, and the effect of dispersion by silicon may not be obtained, and the activity may decrease. Usually, it is preferably 100 ° C. or lower, particularly in the range of 0 to 70 ° C.
[0027]
Examples of the pH regulator include hydroxides such as ammonia, sodium, potassium, and magnesium, carbonates, bicarbonates, oxalates, urea, basic organic compounds, etc. Among these, ammonia is preferable. The pH adjuster may be added to the hydrolyzed solution or suspension as it is, or may be added after being dissolved in a solvent such as water, but it is preferably added after being dissolved in a solvent such as water. The final pH of the hydrolyzed solution or suspension is preferably 4 or higher, more preferably pH 6 or higher.
[0028]
Furthermore, the precipitate and coprecipitate obtained by hydrolysis can be subjected to operations such as solid-liquid separation and washing, drying, firing, and pulverization as necessary.
The precipitate or coprecipitate separated from the hydrolysis reaction product by solid-liquid separation is washed with water or an organic solvent such as ethanol in order to remove impurities, and water is particularly preferable.
[0029]
If necessary, the washed precipitate and coprecipitate can be dried, and the drying can be performed under normal pressure or reduced pressure. The drying temperature is not particularly limited, but is preferably 30 ° C. or higher and lower than 200 ° C., and drying is preferably performed quickly. Furthermore, the obtained precipitate or coprecipitate can be calcined. The firing temperature is usually 200 ° C. to 500 ° C., and the composite oxide is formed by firing.
It is preferable to pulverize the precipitate or coprecipitate after drying and further after firing. The average particle size of the obtained powder after pulverization is preferably 100 μm or less, and more preferably 1 nm or more and 10 μm or less.
[0030]
In the case where a Lewis acid element compound, a Lewis basic element compound and a silicon compound are separately hydrolyzed to obtain a precipitate and a coprecipitate, they can be mixed if necessary. Mixing can be carried out at any stage such as hydrolysis, solid-liquid separation, drying, firing, and before pulverization, and the timing of mixing is not particularly limited. Examples of the mixing method include a method of kneading the hydrolyzed precipitate and coprecipitate in a solvent, a method of mixing in a solid state after drying, and the like.
[0031]
As a preferred embodiment of the catalyst for polyester production of the present invention, a coprecipitate is obtained by hydrolysis in the presence of a pH regulator in a solvent in which a Lewis acidic element compound, a Lewis basic element compound and a silicon compound coexist. The product is separated, and the product is separated, washed with water, dried and pulverized.
Examples of the catalyst for producing a polyester of the present invention obtained as described above include those represented by the following formula (5).
(5) Formula Si_aLA_bLB_c(OH)_xO_y
(Si, O, and H in the formula represent silicon, oxygen, and hydrogen, respectively.
LA and LB represent an element selected as a Lewis acidic element and an element selected as a Lewis basic element, respectively. a, b, c, x and y represent the atomic ratio of each element, and x and y are the atomic ratio of the hydroxyl group and oxygen necessary to satisfy the valence of each component. )
Specifically, Si_aTi_bZn_c(OH)_{4 (a + b) + 2c-2y}O_y, Si_aTi_bMg_c(OH)_{4 (a + b) + 2c-2y}O_yEtc.
[0032]
The polyester production method of the present invention is a polycondensation of a dicarboxylic acid component, particularly a dicarboxylic acid component mainly composed of an aromatic dicarboxylic acid or an ester-forming derivative thereof, and a diol component through an esterification reaction or a transesterification reaction. It is the method of manufacturing polyester by making it.
[0033]
In the present invention, the aromatic dicarboxylic acid which is a dicarboxylic acid component or an ester-forming derivative thereof specifically includes, for example, terephthalic acid, phthalic acid, isophthalic acid, dibromoisophthalic acid, sodium sulfoisophthalate, phenylenedioxy Dicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4,4′-diphenylether dicarboxylic acid, 4,4′-diphenylketone dicarboxylic acid, 4,4′-diphenoxyethanedicarboxylic acid, 4,4′-diphenylsulfonedicarboxylic acid Acids, aromatic dicarboxylic acids such as 2,6-naphthalenedicarboxylic acid, or alkyl esters having about 1 to 4 carbon atoms of these aromatic dicarboxylic acids such as terephthalic acid dimethyl ester and 2,6-naphthalenedicarboxylic acid dimethyl ester, And halides . These may be used alone or in admixture of two or more. Among these, terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and ester-forming derivatives thereof are preferable, and terephthalic acid and ester-forming derivatives thereof are particularly preferable.
[0034]
Examples of the dicarboxylic acid component other than the aromatic dicarboxylic acid and its ester-forming derivative include, for example, alicyclic dicarboxylic acids such as hexahydroterephthalic acid and hexahydroisophthalic acid, and succinic acid, glutaric acid, and adipic acid. , Pimelic acid, suberic acid, azelaic acid, sebacic acid, undecadicarboxylic acid, and aliphatic dicarboxylic acids such as dodecadicarboxylic acid, and these alicyclic dicarboxylic acids and aliphatic dicarboxylic acids having about 1 to 4 carbon atoms. Examples include alkyl esters and halides.
[0035]
Examples of the diol component include ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, decamethylene glycol, neopentyl glycol, 2-ethyl-2-butyl-1,3- Aliphatic diols such as propanediol, diethylene glycol, polyethylene glycol, polytetramethylene ether glycol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,1-cyclohexanedimethylol, 1,4-cyclohexanedimethylol, 2 , 5-norbornane dimethylol and other alicyclic diols, and xylylene glycol, 4,4′-dihydroxybiphenyl, 2,2-bis (4′-hydroxyphenyl) ) Aromatic diols such as propane, 2,2-bis (4′-β-hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, bis (4-β-hydroxyethoxyphenyl) sulfonic acid, and 2 , 2-bis (4′-hydroxyphenyl) propane ethylene oxide adduct or propylene oxide adduct, and two or more of these may be used as components. Among these, ethylene glycol and tetramethylene glycol are preferable, and ethylene glycol is particularly preferable.
[0036]
Furthermore, in order to obtain the desired properties of the polyester, in addition to the above dicarboxylic acid component and diol component, for example, hydroxycarboxylic acids such as glycolic acid, p-hydroxybenzoic acid, p-β-hydroxyethoxybenzoic acid, and alkoxy Carboxylic acid and monofunctional components such as stearyl alcohol, benzyl alcohol, stearic acid, benzoic acid, t-butylbenzoic acid, benzoylbenzoic acid, or tricarbaric acid, trimellitic acid, trimesic acid, pyromellitic acid, gallic acid One or two or more multifunctional components such as trifunctional or trifunctional components such as trimethylolethane, trimethylolpropane, glycerol, and pentaerythritol may be used as a copolymerization component.
[0037]
The method for producing a polyester of the present invention is a method for producing a polyester by esterification, melt polycondensation, and if necessary followed by solid phase polycondensation, but basically a conventional production method for polyester. That is, the presence of an esterification catalyst (for example, an inorganic acid, an alkali metal salt, an alkaline earth metal salt, etc.) in an esterification reaction tank as necessary together with a dicarboxylic acid component and a diol component together with a copolymerization component if necessary. The temperature is usually 240 to 280 ° C., preferably 250 to 270 ° C., usually 0.1 to 0.4 MPa, preferably 0.1 to 0.3 MPa, and the ester is stirred for 1 to 10 hours. To react. Subsequently, the obtained polyester low molecular weight product as an esterification reaction product is transferred to a polycondensation tank, and is usually 260 to 290 ° C., preferably 265 to 285 ° C. in the presence of a polycondensation catalyst which is a catalyst of the present invention. The temperature is gradually reduced from the normal pressure to the normal pressure and finally 1.3 × 10¹~ 1.3 × 10^ThreePa, preferably 6.7 × 10¹~ 6.7 × 10²Under reduced pressure of Pa, melt polycondensation is carried out for 1 to 20 hours with stirring. These operations are performed continuously or batchwise.
[0038]
The polyester resin obtained by melt polycondensation is usually extracted in a strand form from an extraction port provided at the bottom of the polycondensation tank, and is cooled with water or after water cooling and then cut with a cutter to form pellets, chips, etc. It is made of granular material. Furthermore, the granular material after the melt polycondensation is usually 60 to 180 ° C., preferably in an inert gas atmosphere such as nitrogen, carbon dioxide, argon, or the like, or in a water vapor atmosphere or a water vapor-containing inert gas atmosphere. Is heated at a temperature of 150 to 170 ° C. to crystallize the surface of the resin granules, and then in an inert gas atmosphere or / and 1.3 × 10¹~ 1.3 × 10^ThreeUnder reduced pressure of about Pa, usually at a temperature just below or 80 ° C. lower than the adhesive temperature of the resin, preferably 10-60 ° C. lower than the adhesive temperature, It is preferable to perform solid phase polycondensation by heat treatment for a period of 50 hours or less. By this solid-phase polycondensation, the degree of polymerization of the polyester resin can be further increased, and acetaldehyde, low-molecular oligomers and the like as reaction by-products can be reduced.
[0039]
In addition, the polyester resin obtained by melt polycondensation or solid phase polycondensation as described above is usually a water treatment that is immersed in water at 40 ° C. or higher for 10 minutes or more in order to deactivate the polycondensation catalyst, Alternatively, a process such as a steam process in which the steam or steam-containing gas at 60 ° C. or higher is contacted for 30 minutes or more may be performed.
The addition timing of the polycondensation catalyst of the present invention may be any stage of the esterification process or the initial stage of the melt polycondensation process when preparing the slurry with the dicarboxylic acid component and diol component of the raw material. Good.
The method for adding the polycondensation catalyst of the present invention may be in the form of a powder or a solution or slurry of a solvent such as ethylene glycol, and is not particularly limited.
[0040]
It is preferable to add the polycondensation catalyst of this invention so that it may become the range of 0.1-500 ppm as an element chosen as a Lewis acidic element with respect to the theoretical yield of a polyester resin. When the element selected as the Lewis acidic element is a plurality of elements, it is preferably added so that the total amount is in the range of 0.1 to 500 ppm. Furthermore, when the Lewis acidic element is titanium, it is preferable to add it as titanium in a range of 0.1 to 200 ppm.
Furthermore, the polycondensation catalyst of the present invention may be used in the presence of another polycondensation catalyst such as an antimony compound, a germanium compound, a cobalt compound, or a tin compound.
[0041]
In the present invention, an auxiliary agent and a stabilizer for preventing deterioration of the polyester resin can be further used. Auxiliaries and stabilizers include trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, trioctyl phosphate, triphenyl phosphate, tricresyl phosphate and other phosphate esters, methyl acid phosphate, ethyl acid phosphate, isopropyl acid Examples thereof include acidic phosphates such as phosphate, butyl acid phosphate, dibutyl phosphate, monobutyl phosphate, and dioctyl phosphate, and phosphorus compounds such as phosphoric acid, phosphorous acid, and polyphosphoric acid.
These auxiliaries and stabilizers can be supplied when preparing the raw slurry, at any stage of the esterification process and at the beginning of the melt polycondensation process. Auxiliaries and stabilizers are generally used in the range of 1 to 1000 ppm as the weight of phosphorus with respect to the total polycondensation raw material.
[0042]
【Example】
Examples The present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.
The acid value used as an index of intrinsic viscosity and thermal stability in Examples and Comparative Examples was measured as follows.
[0043]
<Intrinsic viscosity [η]>
A polyester resin sample (0.50 g) was mixed with phenol / 1,1,2,2-tetrachloroethane (weight ratio 1/1) at a concentration (c) of 1.0 g / dl at 110 ° C. for 20 minutes. After dissolution, the relative viscosity (η) with the stock solution is measured at 30 ° C. using an Ubbelohde capillary viscosity tube._rel ) And the relative viscosity (η_rel ) -1 specific viscosity (η_sp) And concentration (c) (η_sp/ C). Similarly, when the concentration (c) is 0.5 g / dl, 0.2 g / dl, and 0.1 g / dl, the ratio (η_sp/ C), and from these values, the ratio (η) when the concentration (c) is extrapolated to 0_sp/ C) was determined as intrinsic viscosity [η] (dl / g).
[0044]
<Acid value>
0.50 g of a polyester sample was precisely weighed and collected in a test tube, 25 ml of benzyl alcohol was added, and the mixture was dissolved by heating and stirring at 195 ° C. for 9 minutes. Thereafter, 2 ml of ethanol was added and cooled. This solution was titrated with 0.1N NaOH benzyl alcohol solution. Moreover, said operation was performed without using a polyester sample as a blank, and the acid value was computed with the following formulas.
Acid value (mol / ton) = (A−B) × 0.1 × f / W
Here, the abbreviations are as follows.
A: Amount of 0.1N NaOH required for titration (μl)
B: Blank titration (μl)
W: Amount of polyester sample (g)
f: 0.1N NaOH benzyl alcohol titer
[0045]
<Average electronegativity>
Atomic ions of elements obtained by the method described in Shinichi Tanaka, Catalysis Engineering Course, Vol. 10, Chapter 28, Section 1, Section 5, Section 752, Jijinshokan Tokyo (published on September 20, 1974, Reprint 3) The average electronegativity was calculated using the formula (2) or (4) based on the electronegativity.
[0046]
<Preparation of catalyst>
Example 1
300 ml of ion-exchanged water was weighed, cooled in an ice bath, and then stirred with titanium tetrachloride (TiCl_Four) 20 ml was added dropwise, and when the generation of hydrogen chloride ceased, it was removed from the ice bath. Magnesium chloride hexahydrate (MgCl)₂・ 6H₂4.1 g of O is added and dissolved, and tetraethoxysilane (Si (OC₂H_Five)_Four) Was added and stirred to disperse. While stirring, 4N aqueous ammonia was added dropwise to adjust the pH of the solution to 7.4. The coprecipitate was suction filtered, washed with water, dried under reduced pressure at 80 ° C., and pulverized to 100 μm or less. The atomic ratio and average electronegativity of the obtained catalyst are shown in Table 1.
[0047]
Example 2
300 ml of ion-exchanged water was weighed, cooled in an ice bath, and then stirred with titanium tetrachloride (TiCl_Four) 10 ml was added dropwise, and when the generation of hydrogen chloride ceased, it was removed from the ice bath. Zinc chloride (ZnCl₂20.7 g is added and dissolved, and tetraethoxysilane (Si (OC₂H_Five)_Four26.7 g) was added and dispersed by stirring. While stirring, 4N aqueous ammonia was added dropwise to adjust the pH of the solution to 7.4. The coprecipitate was suction filtered, washed with water, dried under reduced pressure at 80 ° C., and pulverized to 100 μm or less. The atomic ratio and average electronegativity of the obtained catalyst are shown in Table 1.
[0048]
Example 3
300 ml of ion-exchanged water was weighed, cooled in an ice bath, and then stirred with titanium tetrachloride (TiCl_Four) 20 ml was added dropwise, and when the generation of hydrogen chloride ceased, it was removed from the ice bath. Magnesium chloride hexahydrate (MgCl)₂・ 6H₂O) 7.4 g and zinc chloride (ZnCl₂19.9 g is added and dissolved, and tetraethoxysilane (Si (OC₂H_Five)_Four) Was added and stirred to disperse. While stirring, 4N aqueous ammonia was added dropwise to adjust the pH of the solution to 7.4. The coprecipitate was suction filtered, washed with water, dried under reduced pressure at 80 ° C., and pulverized to 100 μm or less. The atomic ratio and average electronegativity of the obtained catalyst are shown in Table 1.
[0049]
Comparative Example 1
300 ml of ion-exchanged water was weighed, cooled in an ice bath, and then stirred with titanium tetrachloride (TiCl_Four35 ml was added dropwise, and when the generation of hydrogen chloride ceased, it was removed from the ice bath. Magnesium chloride hexahydrate (MgCl)₂・ 6H₂7.2 g of O) was added and dissolved. While stirring, 4N aqueous ammonia was added dropwise to adjust the pH of the solution to 7.4. The coprecipitate was suction filtered, washed with water, dried under reduced pressure at 80 ° C., and pulverized to 100 μm or less. The atomic ratio and average electronegativity of the obtained catalyst are shown in Table 1.
[0050]
Comparative Example 2
300 ml of ion-exchanged water was weighed, cooled in an ice bath, and then stirred with titanium tetrachloride (TiCl_Four2 ml was added dropwise, and when the generation of hydrogen chloride stopped, it was taken out from the ice bath. Zinc chloride (ZnCl₂49.7 g is added and dissolved, and tetraethoxysilane (Si (OC₂H_Five)_Four4 g) was added and stirred to disperse. While stirring, 4N aqueous ammonia was added dropwise to adjust the pH of the solution to 7.4. The coprecipitate was suction filtered, washed with water, dried under reduced pressure at 80 ° C., and pulverized to 100 μm or less. The atomic ratio and average electronegativity of the obtained catalyst are shown in Table 1.
[0051]
[Table 1]

[0052]
<Melting polycondensation>
Example 4
In a reaction vessel, 104 g of ethylene terephthalate low polymer produced by direct esterification using terephthalic acid and ethylene glycol as raw materials was melted at 260 ° C., and then the ethylene glycol solution of the catalyst produced in Example 1 was melted. It added so that it might become 100 ppm as a titanium atom with respect to the polyester resin theoretical yield at the time of completion | finish of polycondensation. Next, while stirring the melt with a stirring blade, the temperature is raised stepwise to 280 ° C. in 80 minutes, and the pressure of the reaction system is changed from normal pressure to 1.3 × 10 6 in 60 minutes.²Step down to Pa, temperature 280 ° C, pressure 1.3x10²After reaching Pa, the temperature and pressure were kept constant.
After 111 minutes from the start of depressurization, the stirring was stopped and the polymerization was stopped by introducing nitrogen gas into the reaction system. Thereafter, the polymer was extracted from the reaction vessel and cooled with water to obtain a strand polymer. This was cut into pellets. Table 2 shows the measurement results of the time from the start of decompression to the termination of polymerization (polymerization time), the intrinsic viscosity and the acid value (AV) value of the obtained polymer.
[0053]
Example 5
In Example 4, instead of using the catalyst described in Example 1, the ethylene glycol solution of the catalyst produced in Example 2 was adjusted to 22 ppm as titanium atoms with respect to the theoretical yield of the polyester resin at the end of the melt polycondensation. The same procedure as in Example 4 was conducted except that the polymerization was stopped after 118 minutes from the start of decompression. Table 2 shows the measurement results of the intrinsic viscosity and acid value (AV) value of the obtained polymer.
[0054]
Example 6
In Example 4, instead of using the catalyst described in Example 1, the ethylene glycol solution of the catalyst produced in Example 3 was set to 92 ppm as titanium atoms with respect to the theoretical yield of the polyester resin at the end of the melt polycondensation. The same procedure as in Example 4 was conducted except that the polymerization was stopped after 111 minutes from the start of decompression. Table 2 shows the measurement results of the intrinsic viscosity and acid value (AV) value of the obtained polymer.
[0055]
Comparative Example 3
In Example 4, instead of using the catalyst described in Example 1, the ethylene glycol solution of the catalyst produced in Comparative Example 1 was adjusted to 100 ppm as titanium atoms with respect to the theoretical yield of the polyester resin at the end of the melt polycondensation. The same procedure as in Example 1 was conducted except that the polymerization was stopped after 147 minutes from the start of decompression. Table 2 shows the measurement results of the intrinsic viscosity and acid value (AV) value of the obtained polymer.
[0056]
Comparative Example 4
In Example 4, instead of using the catalyst described in Example 1, an ethylene glycol solution of the catalyst produced in Comparative Example 2 was added to 4 ppm as titanium with respect to the theoretical yield of the polyester resin at the end of the melt polycondensation. Then, the same procedure as in Example 1 was performed except that the polymerization was stopped 158 minutes after the start of decompression. Table 2 shows the measurement results of the intrinsic viscosity and acid value (AV) value of the obtained polymer.
[0057]
[Table 2]

Comparative Example 3 Since Si is not combined, the activity is low.
Comparative Example 4 Since the average electronegativity is <9, the thermal stability of the polymer is poor.
[0058]
【The invention's effect】
According to the present invention, an active ingredient controlled to have a preferable Lewis acid basicity by combining an appropriate Lewis acidic element and an appropriate Lewis basic element is highly dispersed by silicon, for producing a highly active polyester. Since a catalyst can be provided and a polyester having excellent characteristics can be produced with good productivity by using this catalyst, the industrial value of the present invention is high.

Claims (7)

A catalyst for producing a polyester containing at least one atom selected from a silicon atom, a Lewis acidic element, and at least one atom selected from a Lewis basic element, the atom selected from a Lewis acidic element and a Lewis base A silicon compound having an average electronegativity calculated from the electronegativity of each atomic ion of an atom selected from sex elements of 9 to 15 and being an alkoxide, titanium, zirconium, hafnium, iron, cobalt as a Lewis acidic element , A compound of at least one element selected from the group consisting of aluminum, gallium and tin , and a Lewis basic element selected from the group consisting of sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, zinc and cerium At least one element Each or a mixture of hydrolyzate catalyst for polyester production which is characterized in that it is obtained by using the compounds.   The Lewis acidic element compound and the Lewis basic element compound are compounds selected from the group consisting of hydroxide, nitrate, halide, carbonate, carboxylate, alkoxide, and acetylacetonate, respectively. Item 2. The catalyst for producing polyester according to Item 1.   The polyester production catalyst according to claim 1 or 2, wherein the catalyst is a product obtained by hydrolyzing a silicon compound, a Lewis acidic element compound, and a Lewis basic element compound in the presence of coexistence.   The electronegativity of atomic ions of Lewis acidic elements is greater than 10, and the electronegativity of atomic ions of Lewis basic elements is 10 or less. catalyst. The catalyst for producing a polyester according to any one of claims 1 to 4 , comprising titanium as a Lewis acidic element and magnesium or zinc as a Lewis basic element. The ratio (atomic ratio) of the total amount of Lewis acidic element and Lewis basic element to silicon element is 80:20 to 5:95, for producing a polyester according to any one of claims 1 to 5 catalyst. Requested as a catalyst for polyester production in the production of polyester by polycondensation of a dicarboxylic acid component mainly composed of an aromatic dicarboxylic acid or an ester-forming derivative thereof and a diol component through an esterification reaction or a transesterification reaction Item 7. A method for producing a polyester, wherein the catalyst for producing a polyester according to any one of items 1 to 6 is used.