JPS6011748B2 - Manufacturing method for extruded products - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing an extrusion molded product.

More specifically, the present invention relates to a method for stably extruding aromatic polyester, which has a low melt viscosity and is difficult to extrude. Conventionally, aromatic polyesters, particularly polyethylene terephthalate, have been used in various applications such as fibers, films, injection molded products, etc. due to their excellent mechanical properties, chemical resistance, dimensional stability, etc.

However, such aromatic polyesters usually have a low melt viscosity, and when trying to manufacture molded products by extrusion molding, phenomena such as dripping occur. I couldn't use it. On the other hand, in order to improve the melt viscosity of aromatic polyester, attempts have been made to obtain a polymer with a high degree of polymerization using solid phase polymerization or a polymerization accelerator, or to copolymerize with a branching agent, etc., to improve the apparent melt viscosity. Various methods have been developed, but all of them have problems in that they do not have sufficient melt viscosity or require the production of special polymers. The present inventor focused on this point,
As a result of intensive research into a method for producing extrusion molded products using aromatic polyester that has a normal low melt viscosity,
We have arrived at the present invention. That is, in the present invention, when molding an aromatic polyester by extrusion molding, 0.05 to 5% by weight of a jeboxy compound and 0.05 to 3% by weight of {B] of the periodic table are added to the aromatic polyester. This is a method for producing an extrusion molded product, characterized in that one or more selected from Group IA metals, Group OA metals, and compounds thereof are added.

The aromatic polyester used in the present invention is a polyester containing an aromatic dicarboxylic acid as a main acid component, and examples of the aromatic dicarboxylic acid include terephthalic acid,
Examples include isophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenylene dicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenoxychetane dicarboxylic acid, etc., and glycol components include, for example, ethylene glycol, trimethylene glycol, and tetramethylene glycol. , neoventrene glycol,
Hexamethylene glycol, cyclohexane dimethylol, tricyclodecane dimethylol, 2,2-bis(4
, B-hydroxyethoxyphenyl)propane, 4,4
'-bis(8-hydroxyethoxy)diphenylsulfone, diethylene glycol, and the like.

"The above aromatic polyester may include oxyacids such as p-oxybenzoic acid, aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, or pentaerythritol, trimethylolpropane, trimellitic acid, pyro Polyfunctional compounds such as mellitic acid, monofunctional compounds such as benzoic acid, to the extent that the polymer is substantially linear,
It may be copolymerized. The aromatic polyester most preferably used in the present invention includes polyethylene terephthalate, polyethylene 2,6 naphthalene dicarboxylate, and modified polyethylene obtained by copolymerizing these with a third component of 50 mol% or less, more preferably 30 mol% or less. Examples include terephthalate and modified polyethylene 2,6-naphthalene dicarpoxylate.

The intrinsic viscosity of such aromatic polyester is preferably 0.
4 or more, more preferably 0.5 or more. Further, the upper limit is preferably 1.0 or less. The epoxy compound used as a wind component in the present invention is a compound having two epoxy groups in one molecule, for example, 2,2-bis(4
-hydroxyphenyl) propane diglycidyl ether, ethylene glycol diglycidyl ether, diglycidyl phthalate, dicyclobentadiene diepoxide, 3,4-epoxy 6-methylcyclohexylmethyl, 3,4-epoxy 6-methylcyclohexane carboxylate, 3,4-epoxycyclohexylmethyl,
Examples include 3,4-epoxycyclohexane carboxylate and vinylcyclohexene jepoxide.

These can be used in combination of -type or two or more types. The amount of the jepoxy compound added is 0.05 to 5% by weight based on the aromatic polyester. If the amount is less than 0.05% by weight, it will be difficult to achieve the object of the present invention, and phenomena such as dripping will occur during molding.

Moreover, if it exceeds 5% by weight, gelation will occur violently, making it impossible to mold or reducing the mechanical strength of the molded product, which is not preferable. The preferable addition amount is 0.1 to 4
% by weight, especially from 0.5 to 3% by weight. In the present invention, 'B
) As the component, one or more selected from the group consisting of Group IA metals, Group OA metals of the Periodic Table, and compounds thereof are used.

Examples of the metal include lithium, sodium, potassium, magnesium, calcium, and strontium. Examples of the metal compound include organic acid salts, inorganic acid salts, alcoholates, phenolates, hydrides, and oxides of the above metals. As a more specific example,
Lithium acetate, sodium acetate, potassium acetate, magnesium acetate, calcium acetate, calcium propionate, magnesium butyrate, sodium caprylate, sodium caprate, magnesium laurate, calcium stearate, potassium stearate, calcium syristate, calcium benzoate, terephthal acid potassium,
calcium carbonate, sodium bicarbonate, sodium carbonate,
Examples include sodium ethoxide, potassium phenoxide, calcium oxide, sodium oxide, and magnesium oxide. {The amount of component B' added is 0.05 to 3% by weight based on the aromatic polyester. If it is less than 0.05% by weight, it is not preferable because the same problem will occur if the amount of wind component is too small, and if it exceeds 3% by weight, the mechanical properties of the obtained molded product will deteriorate. It is undesirable that it may be colored or colored.

The preferred amount added is 0.1 to 2% by weight, particularly 0.2 to 1.
It is 5% by weight. In the present invention, a molded article is produced by melting the aromatic polyester and then extruding the melt, but it is necessary to add and coexist the above-mentioned D component and 'B' component at the stage of melting the aromatic polyester. It is.

Therefore, in carrying out the present invention, it is possible to use the following method. 1 Aromatic polyester, arc component, and [B-component] at low temperature (for example, 150 qo or less)
After mixing (for example, sprinkling both components), the mixture is subjected to extrusion molding.

2 Sprinkle the other component onto the aromatic polyester obtained by mixing either the breast component or the 'B' component while melting the polymer, or add the other component to the melting zone where the aromatic polyester is melted. Extrusion molding while feeding.

3. The aromatic polyester, the wind component, and the 'B} component are separately combined and molded in the melting zone of an extrusion molding machine.

In the above, aromatic polyester, sheath component and [B'
The temperature at which the components are melted and mixed is preferably in the range from the melting point of the aromatic polyester to 330 qo, and when the melting point of the polyester is less than 200 qo, it is preferably from about 200 oo to 330 qo. According to the method of the present invention, even if aromatic polyester, which normally has problems such as dripping and is difficult to extrude, can be easily extruded.
The molded product obtained has sufficient characteristics of ordinary aromatic polyester and can be used for various purposes. For example, the extrusion molding method of the present invention can be applied to molding pipes, sheets, parisons, etc. The parison can then be applied to so-called direct blow molding, in which bottles and containers are molded by blowing gas or liquid.
The present invention will be explained below with reference to Examples. Note that the netting degree in the examples is a value expressed by the following formula. Necking degree=1-(outer diameter of necking part/outer diameter of non-necking part) If this value is 0, it means that no necking has occurred at all.

The degree of necking is preferably 0.23 or less. If the degree of necking becomes extremely large, the parison will be cut due to drawdown, and even if this does not occur, necking will cause unevenness in the diameter and thickness of the parison, making it impossible to put it into practical use. In addition, during implementation, all parts are parts by weight, [3
] is 1. in orthochlorophenol. Satoshi/d is the intrinsic viscosity measured at a temperature of 35° C. at that concentration.

Examples 1 to 5 and Comparative Examples 1 and 2 polymers were dried with hot air at 160 qo for 3 hours, using a 3-way extruder equipped with an extrusion die (outer diameter 2 wide?, inner diameter 14?) at the tip. supply temperature (L), compression section (T2), metering section (L)
, and the parison was extruded by setting the die (L) at the temperatures shown in Table 1.

In order to quantitatively show the degree of drawdown of the parison at that time, the degree of necking was measured when the parison length was 10 to 12 arcs. Next, the parison was covered with bottle-shaped split molds from both sides, and an air pressure of 6 kg/G was applied in a conventional manner to form a bottle with a diameter of about 50 C.

The results are summarized in Table 1.

The above polymer polyethylene terephthalate is
A material with a softening point of 26〆0, [3]=0.76 was used.

Table 1 Polyethylene terephthalate bottle molding Examples 6 to 8 and Comparative Example 3 Extrusion dies of Examples 1 to 5 with an outer diameter of 1
The pipe was changed to a horizontal one with an inner diameter of 6 sails, and the extrudate was immediately passed through a water bath to form a pipe.

The results are shown in Table 2. Table 2 Pipe molding of polyethylene terephthalate The pipes that were successfully formed had substantially uniform outer diameter and wall thickness.

In addition, those with poor pipe formation had significant unevenness in wall thickness. Comparative Examples 4 and 5 Parisons were extruded in the same manner as in Example 1, except that the molded product composition shown in Table 3 was used, and the degree of netting was measured when the parison length was 10 to 12 arcs.

Next, a bottle was molded in the same manner as in Example 1.

The results are shown in Table 3.

Table 3 Comparative Example of Bottle Molding of Polyethylene Terephthalate 6,7 A pipe was molded in the same manner as in Example 6, except that the ingredients in Table 4 were used as the ingredients.

Claims (1)

[Claims] 1 When molding aromatic polyester by extrusion molding, (A) 0.05 to 5
wt% diepoxy compound and (B) 0.05-3 wt%
A method for producing an extrusion molded product, which comprises adding one or more selected from Group IA metals, Group IIA metals, and compounds thereof of the Periodic Table.