JPH05295099A - Production of high-molecular weight aliphatic polyester - Google Patents

Abstract

PURPOSE:To obtain the subject polymer good in physical properties and moldability, useful as e.g. a molding material by reaction at a specified temperature of a polyfunctional isocyanate with a polymer produced by polymerization between a glycol, aliphatic dicarboxylic acid and trifunctional oxycarboxylic acid in the presence of a catalyst. CONSTITUTION:Firstly, (A) a polyester of >=10000 in number-average molecular weight is prepared by reaction between a glycol component, an aliphatic (including alicyclic) dicarboxylic acid (anhydride) component and a trifunctional oxycarboxylic acid component in the presence of at lest one kind of substance selected from alkoxides of at least one kind of metal selected from zinc, lead, cobalt, iron, zirconium, manganese, antimony, tin, cerium and germanium, organic acid lead salts, oxides and chelate compounds. Then, (B) in such a molten state at a temperature higher than the melting point of this polyester, 0.1-3 pts.wt. of a polyfunctional isocyanate is incorporated in 100 pts.wt. of the polyester to carry out reaction, thus obtaining the objective high-molecular weight aliphatic polyester with a combination of excellent physical properties and the melt viscosity needed for its molding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a high molecular weight aliphatic polyester which can be used for various purposes including molded articles.

[0002]

2. Description of the Related Art Conventionally, since the thermal stability of an aliphatic polyester is insufficient, the molecular weight (number average, the same applies hereinafter) has been limited to about 15,000. It is known that even if various reactions such as esterification and deglycolization are carried out in an attempt to further increase the molecular weight, the reaction for lowering the molecular weight due to thermal decomposition takes precedence and the molecular weight is rather lowered. Thus, it has been extremely difficult to increase the molecular weight of the aliphatic polyester. However, the aliphatic polyester having the above-mentioned molecular weight obtained by the conventional method has not reached the desired level at all even if it has practical physical properties such as strength. The inventors of the present invention have conducted studies to increase the molecular weight of the aliphatic polyester as much as possible to give the aliphatic polyester practicality, and as a result, a glycol compound and a dicarboxylic acid (or an acid anhydride thereof) component alone are the only metal compound. It was reconfirmed that it is extremely difficult to achieve the purpose even if a catalyst is used in combination.
The present invention solves the above-mentioned conventional problems and has both excellent physical properties and a melt viscosity required for molding, and is a high molecular weight aliphatic polyester applicable to various fields such as films, molded products and fibers. It is an object of the present invention to provide a manufacturing method of.

[0003]

As a result of intensive studies, the present inventors were able to solve the above-mentioned conventional problems. That is, the present invention provides (A) (1) glycol component,
(2) Aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) component, (3) trifunctional oxycarboxylic acid component, (4) zinc, lead, cobalt, iron, zirconium, manganese, A polyester having a number average molecular weight of 10,000 or more (reacted in the presence of at least one kind of alkoxide, organic acid salt, oxide or chelate compound of at least one metal selected from the group consisting of antimony, tin, cerium and germanium ( a),
(B) In the molten state above the melting point of the polyester (a), 0.1 to 3 parts by weight of a polyvalent isocyanate is added per 100 parts by weight of the polyester.
A method for producing a high molecular weight aliphatic polyester is provided.

The present invention will be described in more detail below. As a result of the study, the present inventors have used not only a glycol component and a dicarboxylic acid (or an acid anhydride thereof) component but also a trifunctional oxycarboxylic acid component in the reaction system, and further added zinc, lead, cobalt, iron, By reacting at least one kind of alkoxide, organic acid salt, oxide or chelate compound of at least one metal selected from the group consisting of zirconium, manganese, antimony, tin, cerium and germanium, the conventional It was found that a high molecular weight aliphatic polyester having a molecular weight of 20,000 or more can be obtained by the method, which is difficult to achieve. Molecular weight 20,0
When it was 00 or more, it was thought that it could be sufficiently used as a molded article depending on the composition, but the strength was not yet sufficient as a film. Therefore, in order to impart practical properties to the film, 0.1 to 3 parts by weight of a polyvalent isocyanate may be reacted with 100 parts by weight of the polyester in a molten state at a melting point of the desired polyester or higher. It was found to be effective, and the present invention could be completed.

The glycol component that can be used in the present invention is not particularly limited, but for example, ethylene glycol, propylene glycol, butanediol 1,
3, butanediol 1,4, 3-methylpropanediol 1,3, neopentyl glycol, diethylene glycol, dipropylene glycol, 3-methylpentanediol 1,5, hexanediol 1,6,1,4-cyclohexanedimethanol, Examples thereof include hydrogenated bisphenol A, bisphenol A ethylene oxide adduct (each 1 mol adduct), and ethylene glycol and butanediol 1,4 are particularly suitable for the present invention. Further, a monoalkylene epoxide such as ethylene oxide or propylene oxide can be used instead of the glycol component.

The aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) component used in the present invention is, for example, succinic acid, adipic acid, suberic acid, azelaic acid, dodecanedioic acid (or those acids). Anhydride), tetrahydrophthalic anhydride, hexahydrophthalic anhydride and the like. For example, an aromatic dicarboxylic acid (or an acid anhydride thereof) such as terephthalic acid and isophthalic acid may be used in combination as long as it does not hinder the use such as a biodegradable molded article.

The glycol component and the aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) component may be used in substantially equimolar proportions, but preferably the glycol component is 15 moles. It is preferable to use it in excess within a range not exceeding mol%.

The trifunctional oxycarboxylic acid component that can be used in the present invention includes the following two types. (I) A type having one hydroxyl group and two carboxyl groups in the molecule. (Ii) A type having two hydroxyl groups and one carboxyl group in the molecule. Although any of the above trifunctional oxycarboxylic acid components can be used, the malic acid represented by the following formula is particularly useful in the present invention from the viewpoint that a commercial product is easily available at low cost.

[0009]

[Chemical 1]

The use ratio is 0.5 to 5 mol% per 100 mol% of the aliphatic (including cycloaliphatic) dicarboxylic acid (or its acid anhydride) component. If it is less than 0.5 mol%, the effect of the addition becomes small, while if it exceeds 5 mol%, the risk of gelation during the reaction increases remarkably. The most suitable range is 1 to 3 mol%.

The polyester (a) is generally synthesized by esterification and deglycolization of the above components. The conditions include, for example, the esterification reaction
It can be performed at a temperature of 180 to 230 ° C. for 5 to 16 hours. In this case, the acid value is preferably 30 or less. The deglycol reaction is performed at a temperature of 180 to 230 ° C. for 2 to 16 hours at a pressure of 1 Torr or less, and for the deglycol reaction, zinc, lead, cobalt, iron, zirconium, manganese, as a catalyst,
It is preferable to use a compound of at least one metal selected from the group consisting of antimony, tin, cerium and germanium, such as alkoxide, organic acid salt, oxide and chelate compound. The proportion of the catalyst used is 0.01 to 0.5 parts by weight per 100 parts by weight of polyester (a). The reaction with the following polyisocyanates reduces the molecular weight.
In order to obtain a practical high-molecular-weight aliphatic polyester of 20,000 or more, the number average molecular weight of the polyester (a) obtained as described above needs to be 10,000 or more. Desirably, the molecular weight of the polyester (a)
When it is 20,000 or more, the molecular weight can be increased to 30,000 or more by the reaction with the polyvalent isocyanate, and the molecular weight of 20,0 which was difficult by the conventional ordinary esterification and deglycol reaction
High molecular weight aliphatic polyesters of 00 or higher can be produced.

Number average molecular weight 1 obtained as described above
Polyvalent isocyanate is added to the polyester (a) having a molecular weight of 20,000 or more, preferably 20,000 or more in order to further increase the molecular weight. The polyvalent isocyanate that can be used is
It may be those which are generally commercially available and is not particularly limited, but for example, hexamethylene diisocyanate, and its trimer, isophorone diisocyanate, tolylene diisocyanate mixture, 2,4-tolylene diisocyanate, Diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, and the like, in particular, hexamethylene diisocyanate, aliphatic such as isophorone diisocyanate, cycloaliphatic polyvalent isocyanates, polyester It is useful because it does not significantly change the yellow color. The amount of these polyvalent isocyanates added is 0.1 to 3 parts by weight, preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the polyester (a). If the addition amount of the polyvalent isocyanate is less than 0.1 part by weight, the meaning of adding the polyvalent isocyanate is not actually recognized, and if it is more than 3 parts by weight, the risk of gelation becomes high. It is desirable that the addition is carried out under the condition that the polyester is in a uniformly molten state, does not contain a solvent, and can be easily stirred. The high-molecular-weight aliphatic polyester containing a urethane bond of the present invention can be used in combination with a light and heat stabilizer, a filler, a reinforcing material, a coloring agent, waxes, etc., as the case requires. .

[0013]

EXAMPLES In order to facilitate understanding of the present invention, examples will be shown below. Examples 1 to 10 Ethylene glycol 21 was placed in a 1 l separable flask equipped with a stirrer, a fractionating condenser, a thermometer, and a gas introduction tube.
0 g, 354 g of succinic acid, 8 g of malic acid, and the following various metal compounds were added as Examples 1 to 10, respectively. Example 1 Zinc acetate 1.5 g Example 2 Lead acetate 1.5 g Example 3 Cobalt acetylacetonate 2 g Example 4 Iron acetylacetonate 2 g Example 5 Zirconium acetylacetonate 2 g Example 6 Manganese acetate 1.5 g Example 7 Antimony trioxide 1.5 g Example 8 Tin octylate 2 g Example 9 Cerium acetate 1.5 g Example 10 Germanium oxide 2 g Then, as the conditions for esterification, the above Examples 1 to 1 were used.
In both cases, the esterification was carried out at 200 to 205 ° C. in a nitrogen stream to give an acid value of 5 to 10 under a reduced pressure of 0.5 to 0.7 Torr.
The deglycol reaction was performed at 15 to 220 ° C. for 3 hours. To each polyester (a) 300g obtained, 205 ~ 21
In the molten state at 0 ° C, 3.6 g of hexamethylene diisocyanate was added. In both cases, the viscosity increased rapidly, but no gelation occurred. The number average molecular weight and weight average molecular weight of the obtained high molecular weight aliphatic polyester of the present invention were measured. Further, the high molecular weight aliphatic polyester of the present invention was press-molded to form a film, and the film strength (tensile strength) of the film having a thickness of 50 μ and uniaxially stretched 3 times was measured. The results are shown in Table 1. The number average molecular weight of the polyester (a) before reacting with hexamethylene diisocyanate was also measured. The results are also shown in Table 1.

Comparative Example 1 Example 1 above without the use of any malic acid and catalyst.
An attempt was made to produce polyester in the same manner as in No. 10, but the number average molecular weight of the polyester (a) was 6,600.

Comparative Example 2 A high molecular weight aliphatic polyester was produced in the same manner as in Examples 1 to 10 except that 2 g of zirconium acetylacetonate was used as a catalyst without using malic acid, and various molecular weights were measured. Further, a uniaxially stretched film was produced in the same manner as in Examples 1 to 10, and the strength thereof was measured. The results are shown in Table 1. As shown in Table 1, it is clear that by using malic acid and various compounds in combination, high molecular weight can be achieved, and further high physical properties have been achieved by melting reaction of polyvalent isocyanate.

[0016]

[Table 1]

The molecular weight was measured by GPC. The conditions are as follows. Model used Shodex GPC SYSTEM-11 (Showa Denko) Eluent 5mM CF ₃ COONa / HFIP (Hexafluoroisopropanol) Column Sample column HFIP-800P HFIP-80M × 2 Reference column HPIP-800R × 2 Column temperature 40 ° C Flow rate 1.0 ml / min Detector Shodex RI Standard PMMA (Shodex STANDARD M-75)

[0018]

The present invention provides a method for producing a high molecular weight aliphatic polyester which has both excellent physical properties and melt viscosity required for molding and which can be applied to various fields such as films, molded articles and fibers. It

Claims (2)

[Claims] 1. An (A) (1) glycol component, (2) an aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) component, (3) a trifunctional oxycarboxylic acid component, 4) At least one kind of alkoxide, organic acid salt, oxide or chelate compound of at least one kind of metal selected from the group consisting of zinc, lead, cobalt, iron, zirconium, manganese, antimony, tin, cerium and germanium. Number average molecular weight 1 by reacting in the presence
(B) adding 0.1 to 3 parts by weight of a polyvalent isocyanate per 100 parts by weight of the polyester in a molten state above the melting point of the polyester (a). And
Method for producing high molecular weight aliphatic polyester. 2. The proportion of the trifunctional oxycarboxylic acid component used is 0.5 to 5 mol% per 100 mol% of the aliphatic (including cycloaliphatic) dicarboxylic acid (or acid anhydride thereof) component. The method of claim 1.