JPS62109826A - Production of surfactant-containing thermoplastic resin based masterbatch - Google Patents

Abstract

PURPOSE:To prevent slip in an extruder and obtain the titled masterbatch containing a surfactant having antistatic effect in a high concentration, by uniformly blending a liquid surfactant with a molten thermoplastic resin and melt extrusion molding the resultant mixture. CONSTITUTION:(A)20-95wt% anionic, cationic, amphoteric or nonionic sufactant, e.g. alkylbenzenesulfonic acid salt or betaine, and (B) 80-5wt% thermoplastic resin, e.g. polypropylene or polyurethane, are melt kneaded in a kneading machine, e.g. a kneader, e.g. at 150-280 deg.C, and uniformly blended. The resultant mixture is then changed into an extruder, fluidized by applying pressure and heat and extruded into a filamentary material of circular or square cross section, etc., molded, cut to a given length and granulated to afford the aimed masterbatch.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a method for producing a thermoplastic resin masterbatch containing a high concentration of a surfactant, particularly a surfactant having an excellent antistatic effect. The present invention relates to a method for producing a thermoplastic resin masterbatch containing a high concentration of an antistatic agent (hereinafter referred to as an "antistatic agent").

(b) Prior Art Conventionally, antistatic effects have been imparted to thermoplastic resin molded products to prevent staining due to adsorption of dust and the like. In order to impart an antistatic effect, a method of mixing an antistatic agent into a thermoplastic resin is adopted.

A thermoplastic resin molded product containing an antistatic agent is produced by purchasing a thermoplastic resin containing an antistatic agent and molding it into a predetermined shape. However, the current situation is that a thermoplastic resin containing an antistatic agent has a higher 11i than a raw material resin that does not contain an antistatic agent, and therefore the final molded product must also be more expensive.

Recently, attempts have been made to reduce the price of molded products by using a mixture of a masterbatch containing a high concentration of antistatic agent and a raw material resin (also called l#T resin). ing. Therefore, it is preferable that the amount of antistatic agent contained in the masterbatch is as large as possible. However, the amount of antistatic agent that can be contained is generally less than 20% by weight, and it has not been possible to obtain an amount of more than 20% by weight. This is done by putting a large amount of antistatic agent and thermoplastic resin separately into an extruder, melting them under heat and pressure in the extruder, mixing them, and then extruding them.
Because surging occurs due to slipping in some screws of the extruder, stable discharge cannot be obtained, and as a result, the granules cannot be granulated into a uniform shape and cannot be used as a masterbatch. That is, the advantage of a masterbatch, that is, the ability to mix the antistatic agent with the raw material resin to accurately mix the antistatic agent, cannot be achieved, and it becomes impossible to use it as a masterbatch.

For this reason, various methods have been attempted to obtain a masterbatch containing a higher concentration of antistatic agent.

For example, in JP-A No. 57-30746, a highly fluid thermoplastic resin is used as a masterbatch to prevent slippage in the extruder, and an antistatic agent is contained in a higher concentration. A method for producing a masterbatch is disclosed. However, the masterbatch obtained by this manufacturing method has a negative effect on the final molded product because the thermoplastic (H fat) blended in the masterbatch is extremely fluid compared to the commonly used raw material resin, and it is not as good as the raw material resin. It has the disadvantage that it takes a lot of effort to obtain a molded product with physical properties (such as strength).

(c) Problems to be Solved by the Invention Therefore, the present invention aims to prevent slippage in an extruder while using a thermoplastic resin with fluidity equivalent to that commonly used as a raw material resin. The present invention aims to provide a method for producing a masterbatch containing a higher concentration of surfactant.

(d) Means and operation for solving the problem, that is, the present invention is to charge the thermoplastic resin and the surfactant into the extruder instead of charging the thermoplastic resin and the surfactant separately and mixing them in the extruder. This relates to a method for producing a surfactant-containing thermoplastic resin masterbatch by preparing a composition in which a thermoplastic resin and a surfactant are uniformly mixed in advance and feeding the composition into an extruder. be.

The surfactants used in the present invention include fatty acid salts,
Anionic surfactants such as higher alcohol sulfate ester salts, alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl sulfonates, higher alcohol phosphate ester salts, secondary amine salts, ethanolamine ester salts, tetraalkylammonium salts, Pyridium 11 cationic surfactant, hetaine, amphoteric surfactant such as aminoalkyl sulfate ester salt, higher alcohol ethylene oxide adduct, fatty acid ethylene oxide adduct, higher alkylamine ethylene oxide adduct, glycerin heptanofatty acid ester, pentaerythritol fatty acid ester , sorbitol fatty acid ester, and other nonionic surfactants are used.

In the present invention, thermoplastic resins include polypropylene 1 polyethylene, ethylene-vinyl acetate copolymer, polystyrene, acrylonitrilo-styrene copolymer, acrylonitrilo-butadiene-styrene copolymer, and polymethyl methacrylate.

Polyacrylic ester, polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl acecool,
Polyvinylidene chloride, polyurethane.

Polyamide, polycarbonate, saturated polyester, polyacetal, polyphenylene oxide.

Polyphenylene ether, polysulfone, polyether sulfone, polyphenylene sulfide, etc. are used.

In the present invention, the fluidity (melt flow index) of the thermoplastic resin may be any level, but especially the melt flow index (JIS K7210 A method,
It is optimal when the temperature (220° C., 1 load 10 kg) is 80 g/10 minutes, more preferably 50 g/10 minutes or less. This has a melt flow index of 80g/1
When using a thermoplastic resin for more than 0 minutes, a masterbatch containing a high concentration of surfactant can also be obtained by a known method of charging the thermoplastic resin and surfactant into an extruder separately. This is because it is possible.

In order to obtain a molten composition in which a surfactant and a thermoplastic resin are uniformly mixed, the surfactant may be made into a liquid state and the thermoplastic resin may be made into a molten state and kneaded together. To make a surfactant into a liquid state, one that is liquid at room temperature can be used as is, but one that is solid at room temperature in the form of powder or flakes may be heated.

In order to melt the thermoplastic resin, heating may be performed at the melting temperature of the thermoplastic 4N resin. Therefore, various heating temperatures must be set depending on the type of thermoplastic resin.
It is usually in the range of 150 to 280°C.

In order to uniformly mix the surfactant and thermoplastic resin, a conventionally known kneading machine such as a kneader or a ribbon blender may be used. Surfactants and thermoplastics (H fats can be kept in a liquid or molten state when added to a kneading machine such as a kneader, or a heating device can be installed in a kneader etc. to make surfactants and thermoplastics in a solid state. A plastic resin may be charged and made into a liquid or molten state in a kneader or the like.When the surfactant is mixed with a molten thermoplastic resin, it is heated to about the melting temperature of the thermoplastic resin, for example, 240'. If the temperature exceeds C, there is a risk of ignition, so it is necessary to mix in an inert atmosphere.To create an inert atmosphere, fill the kneader with nitrogen gas, argon gas, etc. good.

The molten composition thus obtained may be cooled and solidified, if desired, to form a solid composition.

The solid composition may be in the form of a rod, or may be in the form of powder or granules so that it can be easily fed into an extruder.

In the present invention, it is optimal for the melt composition or the solid composition to have a blending ratio of 20 to 95% by weight of the surfactant and 80 to 5% by weight of the thermoplastic resin. This is due to the feature of the present invention that if the blending ratio of surfactant is less than 20% by weight, only a masterbatch containing a low concentration of surfactant can be obtained, but a masterbatch containing a high concentration of surfactant can be obtained. This is because they cannot demonstrate their full potential. However, it goes without saying that the present invention can also be employed when producing a masterbatch containing a surfactant at a low concentration.

After preparing a molten composition or a solid composition, it is put into an extruder, and in the extruder, pressure and, if necessary, heat are applied to make it fluid and extrusion processing is performed. When the molten composition is introduced into an extruder, heat may not be applied if the molten composition does not lose the desired fluidity in the extruder. Pressure and heat may need to be applied when the solid composition is introduced into the extruder or when the molten composition loses its desired fluidity in the extruder. The extruder used in the present invention refers to one equipped with a pressure section such as a screw or two plunger gears, and a molding section such as a die. Typically, it consists of a heating part that heats the molten composition or solid composition, a screw part that pressurizes and advances the composition, and a goo that molds the composition into a predetermined shape. In the present invention, since a composition in which a thermoplastic resin and a surfactant are uniformly mixed is prepared in advance before being charged into the extruder, the thermoplastic resin and the surfactant are mixed together in the extruder, especially in a part of the screw. The agent will not cause slip. For example, if a solid thermoplastic resin and a powder or liquid surfactant are separately charged into an extruder, the thermoplastic resin and surfactant may slip in the extruder, especially in a part of the screw. The discharge from the goo becomes unstable, making it impossible to obtain molded products of a certain shape.

The composition introduced into the extruder is given a certain shape by a die, and is formed into a filament having a circular or square cross section, for example. Then, it is immediately cooled and then cut into a predetermined length for granulation (obtaining granules of a predetermined shape) to obtain a masterbatch.

(e) Example Using the surfactant as an antistatic agent and the thermoplastic resin shown in Table 1, both were made into a liquid state and a molten state at each mixing temperature, and mixed uniformly to prepare a molten composition. did. Thereafter, the molten composition was cooled and solidified to obtain a solid composition. By putting this solid composition into an axle extruder (equipped with one screw) and extruding it, the mixing ratio of the antistatic agent and thermoplastic resin and the kneading properties as shown in Table 1 can be mastered. Got the batch. Furthermore, an attempt was made to extrude the molten composition by putting it into an extruder in its molten state without converting it into a solid composition, but the same results as those shown in Table 1 were obtained.

(Left below) Table 1-1 Table 1-2 Table 1-3 (Note) 1) MFI:, US X 7210A
method, temperature 220°C.

Measured with a load of 10kg.

2) Mixing ratio; (antistatic agent)/(antistatic + thermoplastic resin) X100 3) Kneadability: Determined by visual observation.

■... No S protrusion of the antistatic agent was observed on the surface.

○: Some oozing of the antistatic agent was observed on the surface.

Δ: Significant oozing of the antistatic agent was observed on the surface.

x: Discharge from the extruder is unstable and cannot be molded by extrusion 4) Hardness: According to JIS K 6301 method.

5) Relative viscosity: Based on JIS K 6810 method.

Next, as a comparative example, Example 1. 3. 7.12.14
Using a surfactant and thermoplastic resin corresponding to ゜15,
Separate twin screw extruder (equipped with two screws)
I tried extrusion processing by putting it in the. The results are shown in Table 2. Moreover, when the same axle-shaft extruder as in the example is used, the kneading property is further reduced by about 50%.

Table 2 1 Table 2 2 (Note) I), 2), 3> are the same as in Table 1.

As is clear from the above Examples and Comparative Examples, according to the Examples, a masterbatch containing a high concentration of surfactant (20% by weight or more) can be obtained, whereas in the Comparative Example, a masterbatch containing a surfactant at a high concentration (20% by weight or more) can be obtained. Only 7 stars of surfactant content can be obtained; if the content is higher than that, it becomes impossible to obtain a masterbatch with a certain shape using an extruder.

Next, as an application example, molded products were obtained by using the masterbatch obtained in the example and diluting the same type of resin as a raw material resin at the weight ratio shown in Table 3. Table 3 shows the physical properties of the molded product obtained.

Table 3 (Note) 6) Weight ratio: (surfactant)/(thermoplastic resin + raw material resin) A range of orders of magnitude is indicated.

8) Izotsu impact strength: Compliant with JIS-6871,
The unit is (kg-cm/cd).

As is clear from the above examples and application examples, the masterbatch according to the example can be used in the same way as a conventional masterbatch containing a low concentration of antistatic agent, and the physical properties of the obtained molded product are also satisfactory. It was possible.

(F) Effects of the Invention According to the method for producing a masterbatch according to the present invention, a masterbatch containing a high concentration (20 to 95% by weight) of a surfactant can be easily produced using a conventional extruder. can. Furthermore, since the surfactant that was conventionally mixed during extrusion processing is mixed with the thermoplastic resin before extrusion processing, even surfactants that could not be mixed during extrusion processing can be mixed and used. be able to.

Moreover, in the method according to the specific invention of the present application, after preparing the molten composition, the molten composition can be prepared as it is! :i (i.e. in a molten state), the process is streamlined compared to the method of solidifying the molten composition to obtain a solid composition and then immersing it in the extruder as in the second invention. It has the effect of being

Although the above description has mainly focused on the case where a surfactant (antistatic agent) having an antistatic effect is used, the present invention also applies to the use of other surfactants, such as a surfactant (illubricant agent) having a lubricating effect.
It can also be suitably used as a lubricant).

Claims (8)

[Claims] (1) A molten composition is prepared by uniformly mixing a liquefied surfactant and a molten thermoplastic resin, and then the molten composition is fed into an extruder in a molten state under the action of pressure. 1. A method for producing a surfactant-containing thermoplastic resin masterbatch, which comprises molding the masterbatch by extrusion processing, and then granulating it into a predetermined shape. (2) Melt flow index of thermoplastic resin (JI
S K 7210A method, temperature 220℃, load 10kg)
80 g/10 minutes or less, the method for producing a surfactant-containing thermoplastic resin masterbatch according to claim (1). (3) Melt flow index of thermoplastic resin (JI
S K 7210A method, temperature 220℃, load 10kg)
The method for producing a surfactant-containing thermoplastic resin masterbatch according to claim (2), wherein the amount is 50 g/10 minutes or less. (4) The molten composition contains 20 to 95% by weight of surfactant and 8
A method for producing a surfactant-containing thermoplastic resin masterbatch according to claim (1), which comprises 0 to 5% by weight of a thermoplastic resin. (5) After uniformly mixing the liquid surfactant and the molten thermoplastic resin to prepare a molten composition, the molten composition is solidified by cooling to form a solid composition;
A surfactant-containing thermoplastic resin characterized in that the solid composition is then put into an extruder in a solid state and extruded under the action of heat and pressure to form the solid composition, and then granulated into a predetermined shape. A method for producing a masterbatch. (6) Melt flow index of thermoplastic resin (JI
S K 7210A method, temperature 220℃, load 10kg)
80 g/10 minutes or less, the method for producing a surfactant-containing thermoplastic resin masterbatch according to claim (5). (7) Melt flow index of thermoplastic resin (JI
S K 7210A method, temperature 220℃, load 10kg)
The method for producing a surfactant-containing thermoplastic resin masterbatch according to claim (6), wherein the amount is 50 g/10 minutes or less. (8) The solid composition contains 20 to 95% by weight of a surfactant and 8
A method for producing a surfactant-containing thermoplastic resin masterbatch according to claim (5), which comprises 0 to 5% by weight of a thermoplastic resin.