Production of polymer composition

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field]

The present invention relates to a method for producing a polymer composition made of a thermoplastic resin containing clay.

【0002】

[Previous technology]

Clay has been dispersed and mixed to improve the characteristics of the resin, but since the compatibility between resin and clay is low, various improvement measures have been taken in the past when dispersing and mixing the two. There is.

【0003】

As a specific example, there is a method in which clay is organically formed into organic clay, which is added and mixed with a polyamide such as nylon 6 together with a swelling agent and a dispersant composed of a monomer such as caprolactam to obtain a composite material (special fairness). 7-47644). There is also a method of kneading organic clay organicated with secondary ammonium with resin and rubber (Special Table 6-504810). There is also a method of kneading the organic clay and the thermoplastic resin under a high shearing force (Japanese Patent Laid-Open No. 9-217012).

【0004】

In addition, as a method of dispersing non-organized clay in a resin, there is a method of mixing a solution of polyamic acid in a basic solvent and an aqueous dispersion of non-organized clay (Japanese Patent Laid-Open No. 9-208822). This method utilizes the fact that polyamide, which is a precursor of polyimide, dissolves in a basic aqueous solution. In addition, a method of introducing water vapor into a mixture of non-organized clay and resin and kneading it (Japanese Patent Application No. 8-331520) has been proposed.

【0005】

The clay-containing resin produced by each of the above methods has improved properties such as the mechanical strength of the resin being enhanced by the clay, and can be used as a new material.

【0006】

[Problems to be solved]

However, in the above-mentioned conventional method, the non-organized clay can be dispersed in a resin having a high affinity with water, for example, polyvinyl alcohol, polyamic acid, polyacrylic acid, etc., but thermoplasticity having a low affinity with water. Dispersion in resins was difficult, and it was difficult to produce materials based on these resins. In addition, if pre-organized clay is used, it can be dispersed in a thermoplastic resin that has a low affinity for water, but the method using organic clay requires a step of organicizing the clay in advance, so that the manufacturing cost and manufacturing cost are increased. It is not very preferable from the viewpoint of simplicity of the manufacturing process.

【0007】

In addition, when the material produced by the conventional method is heated, there is a problem that clay agglutination occurs. That is, the conventional material did not have very high thermal stability. Due to this problem, conventional materials are difficult to heat melt mold.

【0008】

The present invention has been made in view of the above-mentioned conventional problems, and a method for producing a polymer composition having high thermal stability in a dispersed state of clay while clay is uniformly and finely dispersed in various thermoplastic resins. It is what we are trying to provide.

【0009】

[Means for Solving Problems]

The invention according to claim 1 is to prepare a solvent containing water or a proton donor, clay, a clay dispersant, and a thermoplastic resin, and bring them into contact with each other at a temperature equal to or higher than the melting temperature of the thermoplastic resin. The method for producing a polymer composition is characterized by the above.

【0010】

The operation of the present invention will be described. Clay has a layered structure as described later, and Al in the layered structure³⁺Trivalent ions such as Fe²⁺It can be slightly negatively charged by being replaced with a divalent ion such as. Therefore, clay is easily dispersed in water or a solvent containing a proton donor.

【0011】

Therefore, when a solvent containing water or a proton donor comes into contact with clay, the water or solvent intervenes between the layers of the layered structure constituting the clay, the layers of the clay are expanded, and the chemical bond between the layers of the clay is weakened. .. Therefore, the clay is uniformly dispersed in water or a solvent.

【0012】

Further, in the present production method, the thermoplastic resin, the solvent containing water or a proton donor, the clay, and the clay dispersant are contacted at a temperature equal to or higher than the melting point of the thermoplastic resin. That is, since the thermoplastic resin comes into contact with water or a solvent containing a proton donor in a softened state, the solvent containing water or a proton donor is dispersed in the thermoplastic resin, or the molten thermoplastic resin is water or The solvent forms an emulsion.

【0013】

After that, the water or solvent becomes steam and creates a high pressure atmosphere. The chemical bonds between the layers of the clay whose high-pressure atmosphere has become weak are broken, the vapor of water or solvent is allowed to escape from the layers, and instead a thermoplastic resin which has been melted to obtain fluidity is introduced between the layers. At this time, since the layers of the clay have already expanded, the introduction of the thermoplastic resin is carried out smoothly. That is, the clay is finely dispersed in the thermoplastic resin while losing its layered structure.

【0014】

Then, the clay dispersant improves the compatibility between the thermoplastic resin and the clay, and uniformly disperses the clay. Furthermore, since the clay dispersant neutralizes the charge of the clay after the water and the like are exhausted, it is possible to prevent the clay from agglomerating due to electrical suction. As a result, a dispersed state of clay having excellent thermal stability is obtained.

【0015】

As described above, according to the production method of the present invention, there is provided a method for producing a polymer composition and a polymer composition in which clay is uniformly and finely dispersed in various thermoplastic resins and the clay is in a dispersed state and has high thermal stability. can do.

【0016】

Next, the details of the present invention will be described. The solvent containing water or a proton donor is not particularly limited, and for example, water, methanol, ethanol, propanol, diethylene glycol, ethylene glycol, propylene glycol, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol monoacetylate. , Ethylene glycol diacetylate, polyethylene glycol, polypropylene glycol and the like. The solvent containing water or the proton donor may contain a solvent other than water or the proton donor.

【0017】

Next, the clay (clay mineral) is a silicate mineral having a layered structure, and a large number of sheets (some are tetrahedral sheets composed of silicic acid, some are octahedral sheets containing Al, Mg, etc.). It is a substance having a layered structure in which () is laminated.

【0018】

Further, in the present invention, as clay, for example, montmorillonite, saponite, hectorite, byderite, stephensite, nontronite, vermiculite, halloysite, mica, fluorinated mica, kaolinite, pyrophyllite and the like can be used. Moreover, it may be a natural product or a synthetic product.

【0019】

Next, as the clay dispersant, a low molecular weight compound having a molecular weight of 10 to 1,000 or a high molecular weight compound having a molecular weight of 1,000 to 10,000,000 can be used. Compounds with a molecular weight of 10 or less may volatilize when the molten resin is added, and compounds with a molecular weight of more than 10,000,000 may become too viscous during melting, making uniform mixing impossible. The details of the clay dispersant will be described later.

【0020】

The above-mentioned thermoplastic resin is not particularly limited as long as it is a thermoplastic polymer compound, but in particular, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyethylene terephthalate, polybutylene terephthalate, polystyrene, ABS resin (acrylonitrile-butadiene-styrene). Copolymer resin), AS resin (acrylonitrile-styrene copolymer resin), polymethylmethacrylate, polyamide, polyacetal, polycarbonate, polyphenylene sulfide, polyphenylene ether, polyether ether ketone, polysulfone, polyether sulfone, polyamideimide, polyetherimide , Thermoplastic polyimide, natural rubber, isoprene rubber, chloroprene rubber, styrene rubber, nitrile rubber, ethylene-propylene rubber, butadiene rubber, styrene-butadiene rubber, butyl rubber, epichlorohydrin rubber, acrylic rubber, urethane rubber, fluororubber, silicone rubber, etc. Is preferably used. By using these thermoplastic resins, it is possible to obtain a polymer composition in which clay is more uniformly dispersed.

【0021】

Next, the mixing ratio of "solvent containing water or proton donor", "clay", "clay dispersant", "thermoplastic resin" and the like in the present invention will be described. The amount of the clay added in the production method of the present invention is preferably 0.1 to 300 parts by weight with respect to 100 parts by weight of the thermoplastic resin. Thereby, a polymer composition having a well-balanced physical characteristics can be provided. If it is less than 0.1 parts by weight, the rigidity and gas blocking property of the polymer composition may decrease. If it exceeds 300 parts by weight, the impact resistance of the polymer composition may decrease.

【0022】

The amount of the solvent containing water or the proton donor is preferably 0.01 to 1000 parts by weight with respect to 1 part by weight of the clay. As a result, the clay can be reliably and uniformly dispersed in the thermoplastic resin. Further, since the added water or solvent evaporates while the thermoplastic resin is cooled, it is possible to prevent the water or solvent from remaining in the polymer composition. If it is less than 0.01 parts by weight, the degree of swelling of the clay may be insufficient and the clay may not be uniformly dispersed in the thermoplastic resin. On the other hand, when the amount exceeds 1000 parts by weight, the swelling state of the clay is the same as when the amount exceeds 1000 parts by weight, but water or a solvent may remain in the polymer composition.

【0023】

Next, the amount of the solvent containing water or the proton donor added is more preferably 0.1 to 500 parts by weight with respect to 1 part by weight of the clay. If it is less than 0.1 parts by weight, the pressure created by water or solvent vapor is low, and high kneading force may be required to evenly disperse the clay in the thermoplastic resin. It is necessary to devise, and there is a risk of high cost. If it exceeds 500 parts by weight, the temperature of the thermoplastic resin may drop below the melting temperature and solidify due to the latent heat of vaporization due to the evaporation of the solvent. As a result, the clay and the thermoplastic resin may not be kneaded.

【0024】

The amount of the solvent containing water or the proton donor is most preferably 1 to 200 parts by weight with respect to 1 part by weight of the clay. If it is less than 1 part by weight, the pressure created by the solvent vapor is low, and it may take a long kneading time for the clay to disperse in the thermoplastic resin, which may reduce the productivity. If it exceeds 200 parts by weight, a large amount of heat is required to supplement the latent heat of vaporization caused by the solvent, and the amount of heat applied during manufacturing must be increased, which may increase the cost.

【0025】

The amount of the clay dispersant added is preferably 1 to 5000 parts by weight with respect to 100 parts by weight of clay. As a result, uniform dispersion of clay and improvement of thermal stability can be achieved. If the amount added is less than 1 part by weight, the dispersant does not spread to all the clays, so that a sufficient effect may not be obtained. If it exceeds 5000 parts by weight, it may be deposited on the surface of the polymer composition without being adsorbed or bonded to the clay surface.

【0026】

Further, the amount of the clay dispersant added is more preferably 5 parts by weight or more with respect to 100 parts by weight of the clay. If it is less than 5 parts by weight, the amount of adsorption and binding to the clay surface is not sufficient, and uniform dispersion may not be achieved depending on the type of resin. The amount of the clay dispersant added is most preferably 10 to 1000 parts by weight with respect to 100 parts by weight of the clay. If it is less than 10 parts by weight, the amount of adsorption and binding to clay is not sufficient, and even if it is uniformly dispersed, sufficient thermal stability may not be achieved depending on the type of resin. If the amount is more than 1000 parts by weight, some of the clay is not adsorbed or bonded, which may lead to deterioration of the physical properties of the polymer composition.

【0027】

Next, a method of contacting the "solvent containing water or a proton donor", "clay", "clay dispersant", and "thermoplastic resin" in the present invention will be described. In the present invention, a polymer composition is produced by mutual contact between a thermoplastic resin in a molten state, the above-mentioned solvent containing water or a proton donor, clay, and a clay dispersant. In the present invention, the timing of addition of the solvent containing water or the proton donor needs to be at or before the coexistence of the molten thermoplastic resin, clay, and clay dispersant. ..

【0028】

It is preferable to prepare a clay water slurry in which clay is previously dispersed in water or a solvent containing a proton donor, dissolve or disperse the clay dispersant in this slurry, and then contact the clay with the thermoplastic resin. Alternatively, it is preferable to mix the clay dispersant with the thermoplastic resin in the molten state in advance, and add the mixture of both to the above dispersion liquid (a liquid in which clay is dispersed in water or a solvent). In particular, when the clay dispersant is anionic, ion exchange with ions in the clay may occur and the dispersion in water may be insufficient, so the latter method is more preferable.

【0029】

Alternatively, the thermoplastic resin, clay, and clay dispersant may be mixed, heated, and then a solvent containing water or a proton donor may be added. In this case, it is preferable to add water or a solvent after the melt of the thermoplastic resin and the clay or clay dispersant are sufficiently kneaded.

【0030】

Therefore, the water or solvent may coexist with the clay or clay dispersant before the thermoplastic resin is melted, or may be added to the melt after the thermoplastic resin is melted. Further, water or a solvent may be added when the clay, the clay dispersant and the thermoplastic resin are heated to a temperature higher than the melting temperature, or when the melt is kneaded after heating. Alternatively, clay swelled with a solvent may be mixed with a thermoplastic resin and then heated. Alternatively, clay that has been swollen with a solvent after melting the thermoplastic resin may be press-fitted.

【0031】

A specific example will be described. 1) Mix the pellets of the thermoplastic resin with clay and clay dispersant in a dry state, and heat to a temperature higher than the melting temperature of the thermoplastic resin. Water or solvent is injected in the process of melting and flowing the thermoplastic resin. The water or solvent is volatilized in the subsequent steps.

【0032】

2) Mix clay swelled with water or solvent, clay dispersant and thermoplastic resin pellets, and heat to a temperature higher than the melting temperature of the thermoplastic resin. Then, water or solvent volatilizes in the process of melting and flowing the thermoplastic resin. 3) Heat the thermoplastic resin above the melting temperature. In a state where the thermoplastic resin is melted and flowing, the clay dispersant and the clay swollen in water or a solvent are press-fitted into the melted thermoplastic resin.

【0033】

Further, the contact between the thermoplastic resin and the clay or clay dispersant can be carried out by kneading the two. This kneading can be performed by stirring the thermoplastic resin, which has been heated to a melting temperature or higher and is in a molten state, with clay and a clay dispersant. For this stirring, for example, as shown in FIG. 1 described later, a twin-screw kneader for stirring by rotating two screws (rotating shafts) can be used.

【0034】

When a twin-screw kneader (see FIG. 1 described later) is used, the ratio (L / D) of the shaft length (L) to the screw diameter (D) is preferably 10 to 50. If it is less than 10, the stirring power of the twin-screw kneader is small, and it may be difficult to stir efficiently. On the other hand, the larger the L / D, the larger the stirring force can be obtained, but if it exceeds 50, the silicate layer itself constituting the clay may be broken finely and the gas barrier property of the obtained polymer composition may not be improved. There is. The rotation speed of the screw is preferably 100 to 2500 rpm. If it deviates from this range, it may be difficult to stir efficiently.

【0035】

Further, when adding the clay dispersed in water or a solvent to the thermoplastic resin, it is preferable to positively apply pressure to the clay and press-fit it into the thermoplastic resin. The reason is that the water and solvent that intervened between the silicate layers of the clay evaporate due to the heat of the thermoplastic resin, so if no pressure is applied, the water between the layers before the thermoplastic resin intervenes between the clay layers. This is because the solvent evaporates, the swelling effect between these layers disappears, and the thermoplastic resin may not be introduced between the layers. As a method of press-fitting the clay, for example, there is a method of press-fitting the clay into a thermoplastic resin by a liquid feed pump.

【0036】

Further, the contact between the clay dispersed in the solvent and the thermoplastic resin is performed in an environment having a temperature equal to or higher than the melting temperature of the thermoplastic resin. As a result, the thermoplastic resin melts to obtain fluidity, and the clay is dispersed. It should be noted that "above the melting temperature of the thermoplastic resin" differs depending on the type of the thermoplastic resin. Further, it is preferable that the upper limit of the "temperature above the melting temperature of the thermoplastic resin" is the temperature at which the thermoplastic resin does not deteriorate.

【0037】

When the clay, clay dispersant, and thermoplastic resin are brought into contact with each other in the above temperature environment, they may be heated. In this case, it is desirable to keep the clay in a closed state because high pressure steam can be obtained. The closed state is a state in which water or a solvent can be turned into steam by heating to create a high-pressure atmosphere, for example, an internal state of a twin-screw kneader or the like.

【0038】

As in the invention of claim 2, the clay dispersant is preferably made of a substance having a function of being adsorbed or bonded to the clay surface. By adsorbing or binding the clay dispersant to the clay surface, the compatibility between the clay and the thermoplastic resin can be improved. Therefore, it is possible to prevent the layers of clay from shrinking in the thermoplastic resin and forming an aggregated state. Examples of the substance having a function of being adsorbed or bonded to the clay surface include a substance having a functional group and a structure having an affinity with the clay surface as described later.

【0039】

Next, as in the invention of claim 3, the clay dispersant is preferably at least one selected from the substances (1) to (4) described below. (1) A compound having a functional group having an affinity for the clay surface. (2) Metal salt of sulfonic acid, metal salt of phosphonic acid, metal salt of carboxylic acid. (3) Onium salt. (4) Water-soluble polymer. These substances can sufficiently exert an action as a clay dispersant (dispersing clay uniformly and finely in a thermoplastic resin).

【0040】

Examples of the functional group of the compound according to (1) include an acid anhydride group, a carboxylic acid group, a hydroxyl group, a thiol group, an epoxy group, a halogen group, an ester group, an amide group, a urea group, a urethane group, an ether group and a thioether. Examples thereof include functional groups such as a group, a sulfonic acid group, a phosphonic acid group, a nitro group, an amino group, an oxazoline group, an imide group, a cyano group, an isocyanate group and a cyano group. Examples thereof include aromatic rings such as a benzene ring, a pyridine ring, a pyrrole ring, a furan ring and a thiophene ring.

【0041】

Specific examples of (2) above include alkyl sulfonates such as sodium dodecyl sulfonate, alkyl aryl sulfonates such as sodium alkylbenzene sulfonate, aryl sulfonates such as sodium benzene sulfonate, and sodium dodecyl phosphonate. Alkylphosphonates such as, alkylarylphosphonates such as sodium alkylbenzenephosphonate, arylphosphonates such as sodium benzenephosphonate, and the like.

【0042】

Further, as the metal in the metal salt, sodium, potassium, calcium, magnesium, aluminum and the like are preferable.

【0043】

Specific examples of the onium salt according to (3) include ammonium salts such as octyl ammonium chloride, octyl ammonium bromide, dodecyl ammonium chloride, dodecyl ammonium bromide, otatadecyl ammonium chloride, octadecyl ammonium bromide, and aminododecanoate. Examples include phosphonium salts.

【0044】

Further, by using the water-soluble polymer according to (4), not only the above-mentioned effects but also a polymer composition in which clay is uniformly and finely dispersed in a thermoplastic resin having a low affinity for water such as polypropylene and polycarbonate. You can get things.

【0045】

Specific examples of (4) include polyoxyalkylene ethers such as polyethylene glycol and polypropylene glycol, polyoxyaryl ethers such as polyoxyethylene phenol ether, polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, and hirodoxypropyl cellulose. , Cellulose derivatives such as carboxymethyl cellulose, lignin derivatives such as lignin sulfonic acid, chitosan derivatives such as chitosan hydrochloride and the like. Further, polyvinyl sulfonic acid, polyvinyl benzyl sulfonic acid, polyvinyl phosphonic acid, polyvinyl benzyl phosphonic acid, polyacrylic acid and the like can be mentioned.

【0046】

Further, even if it is a substance other than this, it can be used as the clay dispersant according to the present claim as long as it is a substance satisfying the above conditions.

【0047】

Next, in the polymer composition obtained from the present invention, a solvent containing water or a proton donor, clay, a clay dispersant, and a thermoplastic resin are prepared, and these are prepared at a temperature equal to or higher than the melting temperature of the thermoplastic resin. It is characterized in that it is produced by contacting at the temperature of. In the same manner as described above, since the clay is mixed with the melted resin in a state where the cohesive force of the clay is weakened by water, the clay is uniformly and finely dispersed in various thermoplastic resins regardless of the affinity with water. A polymer composition having high thermal stability in a dispersed state of clay can be obtained.

【0048】

Further, in the polymer composition produced in this manner, the uniformly and finely dispersed clay binds the molecular chains of the thermoplastic resin, so that even if the amount of clay dispersed is very small, other fillers and the like are reinforced. Clay exerts a large reinforcing effect that cannot be achieved with materials, and can exert high mechanical strength. In particular, it is possible to obtain a polymer composition having excellent mechanical properties such as strength and elastic modulus, thermal properties such as heat resistance, thermal deformation temperature and low temperature embrittlement temperature, and gas shielding property.

【0049】

Therefore, the obtained polymer composition is lightweight and has high rigidity, and can be used as a structural material for mobile bodies such as those for automobiles and aircraft. In addition, the application is not limited to these, and any field can be used as long as the above-mentioned excellent properties can be utilized.

【0050】

Further, since the polymer composition according to the present invention has high thermal stability in the dispersed state of clay, its characteristics (excellent in mechanical properties, etc.) even when the polymer composition is melted and molded after being manufactured. ) Will not be lost. Therefore, it can be greatly utilized as a material having excellent moldability.

【0051】

BEST MODE FOR CARRYING OUT THE INVENTION

Example 1 A method for producing a polymer composition according to an example of an embodiment of the present invention and the obtained polymer composition will be described with reference to FIG. To explain the outline of the production method of this example, water, clay, a clay dispersant, and a thermoplastic resin are prepared and brought into contact with each other at a temperature equal to or higher than the melting temperature of the thermoplastic resin to form a polymer composition. obtain.

【0052】

Next, the details of the manufacturing method of this example will be described. First, polycarbonate (GE Plastic Lexan 131,) was prepared as a thermoplastic resin. Particulate Na-montmorillonite was prepared as clay. In addition, sodium dodecanesulfonate was prepared as a clay dispersant (Sample 1 of Example 2).

【0053】

As shown in FIG. 1, a twin-screw kneader 1 having two screws 6 and 7 inside a cylinder 9 was prepared. The twin-screw kneader 1 stores a hopper 91, 92, 93 for charging the thermoplastic resin 910, clay 920, and clay dispersant 930 into the cylinder 9, a heater 94 for heating the thermoplastic resin, and water 950. It has a tank 95 and a molding port 96 provided at the rear of the cylinder 9. The water 950 in the tank 95 was press-fitted from the press-in port 952 by the liquid feed pump 951. In addition, a vent 98 was provided to suck and remove water.

【0054】

The amounts of the thermoplastic resin, clay, and clay dispersant added into the cylinder 9 were 9.7 kg / hour, 0.3 kg / hour, and 0.15 kg / hour, respectively. In addition, water 950 is 70 kg / cm by the liquid feed pump 951.²A moderate pressure was applied, and a liquid volume of 7.0 g / min was press-fitted into the cylinder 9.

【0055】

The diameters of screws 6 and 7 were 3.0 cm, the diameter of cylinder 9 was 9.0 cm, and their length was 135 cm. The rotation speed of screws 6 and 7 was set to 100 rpm. The temperature of the heater 94 was 270 ° C. The molding port 96 was opened in a square shape having a size of 0.5 mm × 2 mm.

【0056】

Next, the thermoplastic resin 910 was put into the hopper 91 on the upstream side, and the clay 920 was put into the hopper 92 on the downstream side. In addition, clay dispersant 930 was put in the hopper 93 on the most downstream side. Next, the valves 911,921,931 provided in the outlet pipes of the hoppers 91,92,93 were opened, and the thermoplastic resin 910, clay 920, and clay dispersant 930 were charged into the cylinder 9.

【0057】

Then, the thermoplastic resin was extruded to the downstream side of the cylinder 9 while being kneaded with clay and clay dispersant in a dry state by the rotation of screws 6 and 7. These kneaded products were heated to 300 ° C by a heater 94 to melt the thermoplastic resin.

【0058】

When the melt consisting of the molten thermoplastic resin, clay, and clay dispersant was pushed further downstream by the screw, the melt was kneaded with water 950 press-fitted from the press-in port 95. Since the temperature of the melt is 270 ° C, water gasifies when it comes into contact with the melt and is uniformly dispersed in the melt at the molecular level.

【0059】

The melt was eventually extruded from the molding port 96 of the cylinder 9 and molded into a sheet having a thickness of 0.5 mm. The molded body 4 was carried to the take-up roller 971 by the conveyor 97, and was wound into a roll by the take-up roller 971. The molded body 4 gradually dissipated heat while being carried to the take-up roller 971. In addition, most of the water contained in the molded product was sucked from the vent 98 and evaporated during transportation by the conveyor 97. From the above, a molded product 4 made of a polymer composition was obtained.

【0060】

By the way, Na-montmorillonite has a layered structure composed of a large number of silicate layers laminated. When the molded product 4 obtained by the production method of this example was observed with a transmission electron microscope, the layered structure of montmorillonite collapsed, and 1 to 5 silicate layers having a thickness of about 1 nm were laminated in each of the polycarbonate. It was found that it was evenly dispersed.

【0061】

Further, as shown in Example 2 (Tables 1 to 3) described later, the polymer composition of this example is more than a simple polycarbonate molded product or a molded product made of polycarbonate in which clay is not uniformly dispersed. However, it was found that the tensile elastic modulus, tensile strength, and elongation were large, and the thermal stability was also excellent.

【0062】

In the production of the polymer composition of this example, the thermoplastic resin, clay, and clay dispersant are mixed and heated in a dry state to form a melt in which the thermoplastic resin is in a molten state, and then water is added. Kneaded.

【0063】

Water expands the layers of the layered structure that makes up the clay, and then the water evaporates to form a high-pressure state, while the water escapes from the layers of the clay and instead the thermoplastic resin enters the layers, and the clay has a layered structure. Breaks apart and disperses in the thermoplastic resin. At this time, the clay dispersant adsorbs and binds to the clay surface and works to improve the compatibility between the clay and the resin. Therefore, when the clay is dispersed in the thermoplastic resin, the clay layers shrink to form a condensed state. It is possible to prevent the clay from being dispersed.

【0064】

As a result, the clay can be dispersed in the thermoplastic resin at a certain distance. That is, uniform dispersion of clay is realized. Furthermore, even after the solvent such as water is exhausted, the dispersant is on the clay side, works to neutralize the charge of the clay, and prevents the clay from agglomerating by electrical suction, so the dispersed state of the clay is thermally stable. Excellent in sex.

【0065】

As described above, according to the production method of this example, it is possible to provide a method for producing a polymer composition in which clay is uniformly and finely dispersed in various thermoplastic resins and the clay is in a dispersed state and has high thermal stability. it can.

【0066】

Example 2 In this example, the performance of various polymer compositions prepared by the production method as shown in Example 1 was evaluated together with a comparative sample. Each sample will be described. Sample 1 is prepared by the same material and method as in Example 1. Sample 2 is the same as Sample 1 except that the clay dispersant was changed to dodecyl ammonium chloride (input amount 0.075 kg / hour). Sample 3 is the same as Sample 1 except that the clay dispersant was changed to polyvinyl alcohol (input amount 0.15 kg / hour).

【0067】

In sample 4, nylon 6 (1015B manufactured by Ube Kosan) was used as a thermoplastic resin at an input amount of 9.85 kg / hour, Na-montmorillonite was used as a clay at an input amount of 0.15 kg / hour, and dodecyl was used as a clay dispersant. Sodium sulfonate was used at an input of 0.15 kg / hour. The kneading temperature was 240 ° C. Others are the same as the production method shown in the first embodiment. Sample 5 is the same as Sample 4 except that the clay dispersant was changed to dodecyl ammonium chloride (input amount 0.035 kg / hour). Sample 6 is the same as Sample 4 except that the clay dispersant was changed to polyvinyl alcohol (input amount 0.075 kg / hour).

【0068】

In Sample 7, polypropylene (Mitsubishi Chemical MA2) was used as a thermoplastic resin at an input rate of 9.5 kg / hour, Na-montmorillonite was used as a clay at an input rate of 0.5 kg / hour, and dodecane sulfonic acid was used as a clay dispersant. Sodium was used at an input rate of 0.3 kg / hour. The kneading temperature was 200 ° C. Others are the same as in the first embodiment. Sample 8 is the same as Sample 7 except that the clay dispersant was changed to dodecyl ammonium chloride (input amount 0.1 kg / hour). Sample 9 is the same as Sample 7 except that the clay dispersant was changed to polyvinyl alcohol (input amount 0.2 kg / hour).

【0069】

The method for producing sample 10 is as follows. A clay water slurry was prepared by dispersing 300 g of Na-montmorillonite, which is clay, in 9700 g of water. Then, the thermoplastic resin polycarbonate (GE plastic Lexan 131) was added to the cylinder from the hopper of the twin-screw kneader as shown in Fig. 1 at an input amount of 10.0 kg / hour, and the clay dispersant sodium dodecanesulfonate was similarly added. The mixture was charged at a loading rate of 0.15 kg / hour, kneaded by heating, and melted. Then, the clay water slurry was injected from the injection port of the twin-screw kneader at an input amount of 10 kg / hour, and further melt-kneaded. From the above, the polymer composition of Sample 10 was obtained.

【0070】

Sample 11 is the same as Sample 10 except that the clay dispersant sodium dodecanesulfonate was changed to an input amount of 0.3 kg / hour. Sample 12 is the same as Sample 10 except that the clay dispersant was changed to dodecyl ammonium chloride and the input amount was 0.075 kg / hour. Sample 13 is the same as Sample 10 except that the clay dispersant was changed to polyvinyl alcohol and the input amount was 0.15 kg / hour.

【0071】

The method for producing sample 14 is as follows. A clay water slurry was prepared by dispersing 150 g of Na-montmorillonite, which is clay, in 9850 g of water. Then, nylon 6 (1015B manufactured by Ube Kosan Co., Ltd.), which is a thermoplastic resin, was charged into a cylinder from the hopper of a twin-screw kneader as shown in Fig. 1 at an input amount of 9.85 kg / hour, and similarly, the clay dispersant sodium dodecanesulfonate was added. The mixture was charged at a loading rate of 0.15 kg / hour, kneaded by heating, and melted. Then, the clay water slurry was injected from the injection port of the twin-screw kneader at an input amount of 10 kg / hour, and further melt-kneaded. From the above, the polymer composition of Sample 14 was obtained.

【0072】

Sample 15 is the same as Sample 14 except that the input amount of the clay dispersant sodium dodecanesulfonate was changed to 0.3 kg / hour. Sample 16 is the same as Sample 14 except that the clay dispersant was changed to dodecyl ammonium chloride and the input amount was 0.075 kg / hour. Sample 17 is the same as Sample 14 except that the clay dispersant was changed to polyvinyl alcohol and the input amount was 0.15 kg / hour.

【0073】

The method for producing sample 18 is as follows. A clay water slurry was prepared by dispersing 500 g of Na-montmorillonite, which is clay, in 9500 g of water. Then, polypropylene (Mitsubishi Chemical MA2), a thermoplastic resin, was charged into a cylinder from the hopper of a twin-screw kneader as shown in Fig. 1 with an input amount of 9.5 kg / hour), and the clay dispersant sodium dodecanesulfonate was added in an amount of 0.2. It was charged at kg / hour, kneaded by heating and melted. Then, the clay water slurry was injected from the injection port of the twin-screw kneader at an injection amount of l0 kg / hour, and further melt-kneaded. From the above, the polymer composition of Sample 18 was obtained.

【0074】

Sample 19 is the same as Sample 18 except that the clay dispersant was changed to 0.45 kg / hour in the amount of sodium dodecanesulfonate. Sample 20 is the same as Sample 18 except that the clay dispersant was changed to dodecyl ammonium chloride and the input amount was 0.25 kg / hour. Sample 21 is the same as Sample 18 except that the clay dispersant was changed to polyvinyl alcohol and the input amount was 0.3 kg / hour.

【0075】

The manufacturing method of sample 22 is as follows. A clay water slurry was prepared by dispersing 300 g of Na-montmorillonite as clay and 150 g of sodium dodecanesulfonate as a clay dispersant in 9700 g of water. Then, the thermoplastic resin polycarbonate was poured into a cylinder from the hopper of the twin-screw kneader as shown in FIG. 1 at an injection amount of 10 kg / hour, and the mixture was heated and kneaded to melt. Then, the clay water slurry containing the clay dispersant was charged from the injection port of the twin-screw kneader at an input amount of 10 kg / hour, and further melt-kneaded. From the above, the polymer composition of Sample 22 was obtained.

【0076】

Sample 23 is the same as Sample 22 except that the input amount of the clay dispersant sodium dodecanesulfonate was changed to 300 g. Sample 24 is the same as Sample 22 except that the clay dispersant is changed to 300 g of polyvinyl alcohol.

【0077】

The manufacturing method of sample 25 is as follows. A clay water slurry was prepared by dispersing 150 g of Na-montmorillonite as clay and 75 g of sodium dodecanesulfonate as a clay dispersant in 9850 g of water. Then, nylon 6 of the thermoplastic resin was charged from the hopper of the twin-screw kneader shown in FIG. 1 at an input amount of 10 kg / hour, and was heated and kneaded to melt. Then, the clay water slurry containing the clay dispersant was injected from the injection port of the twin-screw kneader at an input amount of 10 kg / hour, and further melt-kneaded. From the above, the polymer composition according to the sample 25 was obtained.

【0078】

Sample 26 is the same as Sample 25 except that the clay dispersant sodium dodecanesulfonate was changed to 300 g. Sample 27 is the same as Sample 25 except that the clay dispersant polyvinyl alcohol was changed to 300 g.

【0079】

The method for producing sample 28 is as follows. A clay water slurry was prepared by dispersing 500 g of Na-montmorillonite as clay and 250 g of sodium dodecanesulfonate as a clay dispersant in 9500 g of water. Then, polypropylene (Mitsubishi Chemical MA2), a thermoplastic resin, was charged at an input rate of 10 kg / hour from the hopper of the twin-screw kneader shown in Fig. 1, and heat-kneaded to melt. Then, the clay water slurry containing the clay dispersant was injected from the injection port of the twin-screw kneader at an input amount of 10 kg / hour, and further melt-kneaded. From the above, a polymer composition was obtained.

【0080】

Sample 29 is the same as Sample 28 except that the amount of the clay dispersant sodium dodecanesulfonate was changed to 500 g. Sample 30 is the same as Sample 28 except that the clay dispersant was changed to 225 g of polyvinyl alcohol.

【0081】

Next, each comparative sample will be described. Comparative sample C1 is a thermoplastic resin polycarbonate. Comparative sample C2 was melted by charging the thermoplastic resin polycarbonate at an input rate of 9.7 kg / hour and the clay Na-montmorillonite at an input rate of 0.3 kg / hour from the hopper in the twin-screw kneader shown in Fig. 1. It is a polymer composition prepared by kneading.

【0082】

Comparative sample C3 was prepared as follows. 300 g of clay Na-montmorillonite was dispersed in 9700 g of water to obtain a clay water slurry. Next, in the twin-screw kneader shown in FIG. 1, the thermoplastic resin polycarbonate was charged from the hopper at an input amount of 10 kg / hour, and the mixture was heated and kneaded to melt. Then, the clay water slurry was injected from the injection port of the twin-screw kneader at an injection amount of l0 kg / hour, and further melt-kneaded. As a result, a polymer composition for comparative sample C3 was obtained.

【0083】

Comparative sample C4 is nylon 6 of a thermoplastic resin. For the comparative sample C5, the thermoplastic resin nylon 6 was charged at a charge of 9.85 kg / hour and the clay Na-montmorillonite was charged at a charge of 0.15 kg / hour in the twin-screw kneader shown in Fig. 1 and melt-kneaded. And made. Comparative sample C6 is polypropylene, which is a thermoplastic resin. Comparative sample C7 was melt-kneaded in the twin-screw kneader shown in FIG. 1 by charging polypropylene, which is a thermoplastic resin, at an input rate of 95 kg / hour and Na-montmorillonite, which is clay, from a hopper at an input rate of 0.5 kg / hour.

【0084】

Comparative sample C8 was prepared as follows. 500 g of clay Na-montmorillonite was dispersed in 9500 g of water to prepare a clay water slurry. Next, in the twin-screw kneader shown in FIG. 1, polypropylene, which is a thermoplastic resin, was charged from a hopper at an input amount of 10 kg / hour, and was heated and kneaded to melt. Then, the clay water slurry (10 kg / hour) was injected from the injection port, and further melt-kneaded. As a result, a polymer composition for comparative sample C8 was obtained.

【0085】

Next, a method for evaluating the performance of these samples and comparative samples will be described. First, the amount of clay in each sample and comparative sample was measured by the method, and is shown in Tables 1 to 3.

【0086】

The dispersed state of clay was evaluated as follows by observation with an optical microscope and a transmission electron microscope, and is shown in Tables 1 to 3. : Dispersion at the nano level, 1 to 5 layers of sheets that make up clay. : Dispersion at the nano level, 1 to 10 layers of sheets that make up clay. Δ: Submicron level dispersion. ×: Dispersion (aggregation) above the micron level .

【0087】

In addition, the mechanical properties were evaluated by a tensile test. This tensile test was performed according to JIS K 7113 at a measurement temperature of 25 ° C and a head speed of 5 mm / min. The tensile elastic modulus, tensile strength, and elongation were measured by this test and are shown in Tables 1 to 3.

【0088】

The following tests were conducted for thermal stability. 10 g of each sample and comparative sample were weighed, placed in a heating cylinder having a diameter of 2 cm and melted, and then the shaft was brought into contact with the surface of the melted sample and the comparative sample. This shaft was rotated at 50 rpm for 5 minutes. After that, the sample and the comparative sample were taken out from the cylinder, and the dispersed state of the clay was observed with an optical microscope and a transmission electron microscope. The observation results were evaluated as follows and are shown in Tables 1 to 3. O: Dispersed at the nano level without change. Δ: Submicron level agglutination. ×: There is agglutination of micron level or higher.

【0089】

Here, Samples 1 to 3, Samples 10 to 13, and Samples 23 to 24 are polymer compositions containing polycarbonate prepared by the production method according to the present invention. Comparative sample C1 is a simple polycarbonate resin, and comparative samples C2 and C3 are polycarbonate resins containing clay, but no clay dispersant is used in the production.

【0090】

As can be seen from Tables 1 to 3, Samples 1 to 3, Samples 10 to 13, and Samples 23 to 24 according to the present invention have a much higher tensile elastic modulus and tensile strength as compared with Comparative Sample C1 which is a simple polycarbonate resin. The growth was found to be equal to or greater than that. Moreover, since it is excellent in thermal stability and the dispersed state of clay does not change even after heating and melting, it is found that the above characteristics are not lost even if each of these samples is prepared and then heat-molded. It was.

【0091】

On the other hand, it was found that the clay was not finely dispersed in the comparative sample C2, the tensile elastic modulus was about the same as that of the comparative sample C1, and the tensile strength and elongation were lower than this. In addition, the comparative sample C3 has excellent tensile modulus and the like immediately after production as well as the sample according to the present invention, but is inferior in thermal stability because clay aggregates at the submicron level after heating and melting. I found out.

【0092】

Samples 4 to 6, samples 14 to 17, and samples 25 to 27 are polymer compositions containing nylon 6 produced by the production method according to the present invention, and comparative sample C4 is simply nylon 6, comparative sample. C5 is nylon 6 containing clay, but no clay dispersant is used in the production. As can be seen from the table, it was found that the sample according to the present invention had a larger tensile elastic modulus, tensile strength, and elongation than the comparative sample C4. It was also found that the comparative sample C5 was inferior to the comparative sample C5 of nylon 6 alone in the above performance.

【0093】

Samples 7 to 9, samples 18 to 21, and samples 28 to 30 are polymer compositions containing polypropylene produced by the production method according to the present invention. Comparative samples C6 are simply polypropylene, and C7 and C8 are simple polypropylene. No clay dispersant is used in the production. As can be seen from the table, it was found that the sample according to the present invention had a significantly superior tensile elastic modulus, excellent tensile strength and elongation, and excellent thermal stability. It was found that the comparative sample C7 was inferior to the comparative sample C6 of polypropylene alone in the above performance. Further, it was found that the comparative sample C8 exhibited the same performance as that of the present invention in terms of the above performance, but was inferior in thermal stability.

【0094】

From the above, it was found that in the polymer composition produced by the production method according to the present invention, clay was uniformly and finely dispersed in various thermoplastic resins, and this dispersed state was excellent in thermal stability. .. Further, it was found that the polymer composition according to the present invention exhibits the same or better performance in tensile elastic modulus, tensile strength, and elongation than the composition of the thermoplastic resin alone.

【0095】

[table 1]

<img file="JP2000239397A_D0001.tif" />【0096】

[Table 2]

<img file="JP2000239397A_D0002.tif" />【0097】

[Table 3]

<img file="JP2000239397A_D0003.tif" />【0098】

[Effect of the invention]

As described above, according to the present invention, it is possible to provide a method for producing a polymer composition in which clay is uniformly and finely dispersed in various thermoplastic resins and the clay is in a dispersed state and has high thermal stability.

[Simple explanation of drawings]

[Figure 1]

The explanatory view which shows the structure of the twin-screw kneader in Embodiment 1.

[Explanation of symbols]

910 ... Thermoplastic resin, 920 ... Clay, 930 ... Clay Dispersant, 950 ... Wed,