Polyester and method for producing the same

Abstract

A polyester which is produced with a polymerization catalyst containing metals other than antimony and germanium as major metallic ingredients and which is reduced in filter clogging during molding, etc. The polyester contains at least one member selected from the group consisting of alkali metals, alkali metal compounds, alkaline earth metals, and alkaline earth metal compounds and at least one member selected from the group consisting of aluminum and compounds thereof, the contents of these satisfying the following relationships (1) and (2). [M] < 0.05 (1) [M] / [Al] C08G 63 / 84 0 84 0 2002 / 1 / 17 1486336 2004 / 3 / 31 100480300 2009 / 4 / 22 2009 / 4 / 22 2009 / 4 / 22 Toyobo Co., Ltd. Japan Nakajima Takahiro Gyobu Shoichi Tsukamoto Kenichi zhu dan 11021 The Patent Agency of the Chinese Academy of Sciences Inside the Chinese Academy of Sciences, No.52 Sanlihe Road, Fuwai, Beijing 100864 Japan 2001 / 1 / 18 10474 / 2001 Japan 2001 / 2 / 20 43106 / 2001 Japan 2001 / 2 / 20 43118 / 2001 Japan 2001 / 2 / 21 44629 / 2001 Japan 2001 / 2 / 22 47101 / 2001 Japan 2001 / 3 / 7 63902 / 2001 Japan 2001 / 4 / 3 104985 / 2001 Japan 2001 / 9 / 17 282044 / 2001 Japan 2001 / 9 / 28 302937 / 2001 Japan 2001 / 9 / 28 302938 / 2001 2003 / 7 / 17 PCT / JP2002 / 000266 2002 / 1 / 17 WO2002 / 057335 2002 / 7 / 25 Japanese

Description

technical field [0001] The present invention relates to a polyester polymerization catalyst, a polyester, and a method for producing polyester, and more particularly, to a polyester polymerization catalyst, polyester, and a method for producing polyester that can improve filter clogging during molding, etc. . Background technique [0002] Polyester, especially polyethylene terephthalate (hereinafter referred to as PET), has excellent mechanical and chemical properties and is used in various applications, for example, it can be applied to clothing, fibers for industrial resources, and packaging Formed products of various films or sheets, bottles or engineering plastics, etc. [0003] PET, in the industry, bis(2-hydroxyethyl) terephthalate is prepared by esterification or transesterification between terephthalic acid or dimethyl terephthalate and ethylene glycol, and then heated at high temperature It can be obtained by polycondensation using a catalyst under vacuum. Antimo...

AI Technical Summary

Problems solved by technology

Antimony trioxide is an inexpensive catalyst with excellent catalytic activity, but there is a problem of black ink or impurities in PET due to the precipitation of antimony metal during polycondensation

In addition, when used as a raw material for hollow molded products, etc., it is difficult to obtain hollow molded products with good transparency.

[0006] (2) Impurities in the polyester used for fiber will reduce the strength in the fiber, causing cover contamination during silk making or increase in filter pressure of the filter

Among them, chelates of aluminum such as aluminum acetylacetate are generally expensive, and the aluminum content in the compound is low, so it will cause the problem of high cost or the problem of low solubility in solvents such as ethylene glycol, which limits the problem of adding methods.

Aluminum hydroxide or aluminum alkoxide, which has the problem of low solubility into the system and thus low catalytic activity or the problem of producing insoluble impurities in the polyester

Chlorine-containing inorganic acid salts such as aluminum chloride have relatively excellent catalytic activity, but they have a problem of high corrosion to equipment or a large coloring of the obtained polymer.

[0018] On the other hand, examples of aluminum salts of carboxylic acids include aluminum acetate, basic aluminum acetate, aluminum lactate, and aluminum benzoate. These are generally inexpensive and have low corrosion resistance to equipment. However, due to their solubility in polyester Low, so it has an impact on catalytic activity, and at the same time, there is a problem of turbidity in the obtained polyester, and there are problems in using it as a catalyst

For example, it is disclosed in JP-A-10-324741 that the polyester using aluminum acetate as a catalyst has the problem that insoluble impurities are easily formed and the spinning properties are poor.

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