JP4885652B2 - Method for evaluating permeability of fluid through material containing resin, method for treating material containing biodegradable resin, material containing biodegradable resin, and biodegradable resin molded article - Google Patents

Description

  The present invention relates to a method for evaluating fluid permeability through a material containing a resin, a method for treating a material containing a biodegradable resin, a material containing a biodegradable resin, and a biodegradable resin molded article.

  In recent years, from the viewpoint of environmental protection, it has been proposed to use biodegradable resins that can be decomposed by microorganisms for daily consumer goods such as cosmetic containers. On the other hand, as for the material of the container and the packaging material, the substance contained in the container and the substance to be packaged are oxidized by oxygen in the air and absorb or adsorb moisture in the air. Therefore, it is required to reduce deterioration. For this reason, it is desired that the material of the container and the packaging material are materials having performance (gas / moisture barrier properties) for blocking oxygen and moisture in the air from permeating into the container. However, the conventional biodegradable resin has low performance for blocking permeation of oxygen and moisture in the air, and it is not preferable to use the conventional biodegradable resin for containers and packaging.

  Therefore, in order to improve the gas / water barrier property of the material containing the biodegradable resin, a nanocomposite in which a minute additive is dispersed in the biodegradable resin has been proposed. For example, Patent Document 1 discloses a biodegradable gas barrier material comprising a polyester having lactic acid as a main repeating unit and a swellable layered silicate. In a nanocomposite in which a minute additive is dispersed in such a degradable resin, the minute additive dispersed in the biodegradable resin indicates that oxygen and moisture in the air permeate the biodegradable resin. Inhibit. In this way, the gas / water content of the nanocomposite in which the minute additive is dispersed in the degradable resin due to the ability of the minute additive dispersed in the biodegradable resin to block the permeation of oxygen and moisture in the air. The barrier property can be improved.

  However, in a nanocomposite in which a minute additive is dispersed in a biodegradable resin, the minute additive dispersed in the biodegradable resin prevents oxygen and moisture in the air from permeating through the biodegradable resin. Therefore, the gas / water barrier property of the biodegradable resin itself is not improved.

In Non-Patent Document 1, a nylon / clay composite test product in which montmorillonite is blended with nylon-6 is used to conduct a heat aging test with a heating temperature of 100 ° C. and a heating time of up to 240 hours. The result of the measurement of tan δ _max is disclosed as the dynamic viscoelasticity performed on the test product after finishing the above.

  In addition, in order to improve the gas / water barrier property of the biodegradable resin, a biodegradable resin in which the crystallinity of the biodegradable resin is adjusted by heat-treating the biodegradable resin has also been proposed. Here, the crystallinity of the biodegradable resin means the ratio of crystal parts to the whole biodegradable resin. That is, when the biodegradable resin is heated to a temperature higher than the crystallization temperature of the biodegradable resin and then cooled, the biodegradable resin crystallizes. Oxygen and moisture in the air relatively easily permeate the amorphous part of the biodegradable resin, but cannot easily permeate the crystal part where the molecules are densely and regularly arranged. Thus, by heat-treating the biodegradable resin, the ratio of crystal parts in the biodegradable resin can be increased, and the gas / water barrier property of the biodegradable resin can be improved.

  However, the gas / moisture barrier properties of the biodegradable resin, which is improved by adjusting the crystallinity of the biodegradable resin, largely depend on the conditions of the crystallization treatment for crystallizing the biodegradable resin. The correlation between the crystallinity of the functional resin and the gas / water barrier property of the biodegradable resin is not high. That is, even if the biodegradable resin has the same crystallinity, the gas / moisture barrier properties of the biodegradable resin may differ greatly. Therefore, in practice, it is insufficient to evaluate the gas / water barrier property of the biodegradable resin by the crystallinity of the biodegradable resin.

  Furthermore, Patent Document 2 discloses that at least one amide repeating unit selected from the group consisting of a metaxylylene adipamide unit, a metaxylylene isophthalamide unit, and a metaxylylene terephthalamide unit is added to the entire resin. A tensile mode under the condition that the water absorption of the amorphous part at 25 ° C. and 100% relative humidity is 8% by weight or less, the frequency is 10 Hz, and the strain is 0.05%. A polyamide resin excellent in gas barrier properties is disclosed, characterized in that the activation energy of β relaxation in the temperature dispersion spectrum of dynamic viscoelasticity measured in (1) is 18 kJ / mol or less.

However, the prior art disclosed in Patent Document 2 provides a polyamide resin excellent in gas barrier properties, and discloses a technology for improving gas / moisture barrier properties of a material containing a general biodegradable resin. It does not disclose a technique for evaluating the gas / moisture barrier properties of a material containing a general biodegradable resin. In particular, there is no disclosure or suggestion of a technique for improving or evaluating a gas / water barrier property of a material containing a biodegradable resin such as polylactic acid.
JP 2002-338996 A JP-A-9-95532 Polymer Preprints, Japan Vo. 53, no. 2 (2004) pages 3652 to 3653

  One of the objects of the present invention is to provide a method for evaluating the permeability of a fluid through a material containing a resin, which can more appropriately evaluate the permeability of a fluid that passes through the material containing a resin. .

  Another object of the present invention is to provide a method for treating a material containing a biodegradable resin, which can more appropriately reduce the permeability of a fluid that passes through the material containing the biodegradable resin.

  Yet another object of the present invention is to provide a material comprising a biodegradable resin in which the permeability of the permeating fluid is more appropriately reduced.

  Still another object of the present invention is to provide a biodegradable resin molded article in which the permeability of a fluid to be permeated is more appropriately reduced.

A first aspect of the present invention includes a resin characterized in that the permeability of a fluid that permeates the material containing the resin is evaluated using loss tangent by dynamic viscoelasticity measurement of the material containing the resin. This is a method for evaluating the permeability of a fluid through a material.

A reference example is a method for treating a material containing a biodegradable resin, wherein the material containing the biodegradable resin is heated at a temperature of 90 ° C. or higher and 140 ° C. or lower for 5 minutes or longer, preferably 30 minutes or longer. is there.

A second aspect of the present invention is a material containing a biodegradable resin, the loss tangent by dynamic viscoelasticity measurement of the material containing the biodegradable resin at the α transition point of the material containing the biodegradable resin Is a material containing a biodegradable resin, characterized by being 0.2 or less.

A third aspect of the present invention is a material containing a biodegradable resin, the loss tangent by dynamic viscoelasticity measurement of the material containing the biodegradable resin at the α transition point of the material containing the biodegradable resin Is a material containing a biodegradable resin, characterized by being 0.2 or less.

A fourth aspect of the present invention is a biodegradable resin molded article obtained by molding a material containing a biodegradable resin according to the second aspect of the present invention or the third aspect of the present invention. It is.

  According to the first aspect of the present invention, there is provided a method for evaluating the permeability of a fluid through a material containing a resin, which can more appropriately evaluate the permeability of a fluid that passes through the material containing a resin. Can do.

According to the reference example , it is possible to provide a method for treating a material containing a biodegradable resin, which can more appropriately reduce the permeability of a fluid that passes through the material containing the biodegradable resin.

According to the 2nd or 3rd aspect of this invention, the material containing the biodegradable resin by which the permeability | transmittance of the fluid which permeate | transmits was reduced more appropriately can be provided.

According to the fourth aspect of the present invention, it is possible to provide a biodegradable resin molded body in which the permeability of the fluid that permeates is appropriately reduced.

  Next, embodiments of the present invention will be described with reference to the drawings.

  The first embodiment of the present invention evaluates the permeability of a fluid that permeates a material containing a resin using a loss tangent of the material containing a resin in a method for evaluating the permeability of a fluid through a material containing a resin. It is characterized by that.

  Here, the material containing the resin may be a material composed only of the resin, or may be a composition containing the resin and additives other than the resin. The resin may be a single resin or a combination of a plurality of resins. The resin is not particularly limited, and may be a biodegradable resin or a non-biodegradable resin. Examples of the biodegradable resin include polyester resins such as polylactic acid, polyesteramide resins, polyester carbonate resins, polysaccharides (polysaccharides), polypeptides, lignin, and derivatives thereof. Examples of additives include known organically modified clay minerals, additives, antioxidants, heat stabilizers, ultraviolet absorbers, lubricants, antistatic agents, flame retardants, crystallization accelerators, endblockers, and A filler etc. are mentioned. The known organically modified clay mineral is obtained by replacing at least one of the inorganic cations of the clay mineral with an organic cation, and by dispersing the organically modified clay mineral in the resin-containing material, Fluid permeability can be reduced.

  The fluid that permeates the resin is a gas or a liquid and is not particularly limited, and examples thereof include oxygen and moisture in the air.

  The loss tangent of the resin-containing material is measured using a known dynamic viscoelasticity measuring device, for example, as described in Japan Industrial Standards Committee TRK0005 "Plastics-Determination of transition temperature by dynamic mechanical properties". It is measured by a known measurement method. In other words, the loss tangent of the resin-containing material is tested when the dynamic viscoelasticity measuring device holds the specimen of the resin-containing material with a clamp and applies a sinusoidal strain to the specimen of the resin-containing material. This is a tangent tan δ of the phase difference δ between the stress generated in the test piece and the sinusoidal strain applied to the test piece.

  The loss tangent tan δ of the material including the resin represents the viscous component of the stress generated in the material including the resin with respect to the elastic component of the stress generated in the material including the resin. Therefore, when the elastic component of the stress generated in the material containing resin increases, the value of the loss tangent tan δ of the material containing the resin decreases, and when the viscous component of the stress generated in the material containing the resin increases, the loss of the material containing the resin The value of tangent tan δ increases.

  On the other hand, when the mobility of the molecules constituting the resin-containing material decreases, the molecules constituting the resin-containing material are closely arranged, and the elastic component of the stress generated in the resin-containing material increases, thereby including the resin. The value of the loss tangent tan δ of the material is expected to be small. Conversely, when the mobility of the molecules that make up the resin-containing material is improved, the molecules that make up the resin-containing material are sparsely arranged, increasing the viscous component of the stress generated in the resin-containing material, The value of the loss tangent tan δ of the contained material is expected to increase.

  In addition, when the mobility of molecules constituting the resin-containing material is lowered, the molecules constituting the resin-containing material are closely arranged, and the fluid permeability through the resin-containing material is considered to decrease. On the contrary, when the mobility of the molecules constituting the resin-containing material is improved, the molecules constituting the resin-containing material are arranged sparsely, and the fluid permeability through the resin-containing material is considered to increase.

  Therefore, when the value of the loss tangent tan δ of the material containing the resin is small, the permeability of the fluid through the material containing the resin is decreased, and when the value of the loss tangent tan δ of the material containing the resin is large, the permeability through the material containing the resin is reduced. The fluid permeability is expected to increase.

The present inventor found that the correlation between the loss tangent of the resin-containing material and the fluid permeability through the resin-containing material indicates that the crystallinity of the resin-containing material and the fluid permeability through the resin-containing material are It was discovered that the correlation was higher. The crystallinity of the material containing the resin is the ratio of the crystal part in the entire material containing the resin, which is composed of a crystal part and an amorphous part, and corresponds to the crystal part obtained by a known X-ray structural analysis. From the area of the narrow peak and the area of the narrow peak corresponding to the amorphous part,
Crystal part = (Narrow peak area) / {(Narrow peak area) + (Wide peak area)}
Is a value calculated according to In other words, the present inventor believes that the fluid permeability through the resin-containing material reflects the proportion of crystal parts in the entire resin-containing material, rather than the crystallinity of the resin-containing material. Has been found to be properly evaluated by using the loss tangent of the resin-containing material, which reflects the mobility of the molecules that make up.

  Therefore, according to the first embodiment of the present invention, the loss tangent of the resin-containing material is used to evaluate the permeability of the fluid that passes through the resin-containing material. It is possible to provide a method for evaluating the permeability of a fluid through a material including a resin, which can more appropriately evaluate the permeability.

  In the first embodiment of the present invention, the loss tangent of the material containing the resin preferably includes the resin at the phase transition point of the material containing the resin. The loss tangent of the material.

  The loss tangent tan δ of the material containing the resin varies depending on the temperature of the material containing the resin. That is, because the mobility of molecules that make up the resin-containing material varies depending on the temperature of the material that contains the resin, the loss of the material that contains the resin reflects the mobility of the molecules that make up the resin-containing material. The tangent tan δ also varies depending on the temperature of the material containing the resin.

  In particular, when the temperature of the material containing the resin is changed, a phase transition such as glass transition, crystallization, softening, or melting may occur in the material containing the resin. When a phase transition such as a glass transition occurs in a material containing a resin, the mobility of molecules constituting the resin-containing material is greatly changed, so that the arrangement of molecules constituting the material containing the resin is also greatly changed. As a result, the ratio of the elastic component and the viscous component of the stress generated in the material containing the resin changes rapidly, and the value of the loss tangent tan δ of the material containing the resin also varies greatly.

The inventor surprisingly found that the loss tangent tan δ _max of the resin-containing material at the phase transition point of the resin-containing material is such that the crystallinity of the resin-containing material and the fluid permeability through the resin-containing material. It was discovered that the correlation may be higher. Note that the phase transition point of a material including a resin is a temperature at which a phase transition occurs in the material including the resin. The present inventor found that the loss tangent tan δ _{max of the} material containing the resin at the temperature at which the phase transition occurs is higher than the crystallinity of the material containing the resin measured at room temperature, and the fluid permeability through the material containing the resin at room temperature. And found that there is a high correlation.

  Based on the discovery of this inventor, by using the loss tangent of the resin-containing material at the phase transition point of the resin-containing material as the loss tangent of the resin-containing material, the permeability of the fluid that passes through the resin-containing material is used. May be more appropriately evaluated.

  In particular, since the loss tangent of the resin-containing material at the phase transition point of the resin-containing material is an extreme value of the loss tangent of the resin-containing material with respect to the temperature of the resin-containing material, it is easier and more accurate. It is obtained by. That is, by using the loss tangent of the resin-containing material at the phase transition point of the resin-containing material as the loss tangent of the resin-containing material, the permeability of the fluid that passes through the resin-containing material can be made easier and more It may be possible to evaluate with high accuracy.

  In the first embodiment of the present invention, in the method for evaluating fluid permeability through a resin-containing material, preferably, the loss tangent of the resin-containing material at the phase transition point of the resin-containing material includes the resin. It is the loss tangent of the material including the resin at the α transition point of the material.

When the temperature of the material containing the resin is changed, the material containing the resin at the α transition point where the glass transition occurs in the material containing the resin (the main chain of the resin molecules constituting the material containing the resin moves). The value of the loss tangent tan δ is an extreme value. For example, when the temperature of the material containing the resin is increased, the value of the loss tangent tan δ of the material containing the resin becomes the maximum value tan δ _max at the α transition point.

  The inventor surprisingly found that the loss tangent of the resin-containing material at the alpha transition point of the resin-containing material correlates with the crystallinity of the resin-containing material and the fluid permeability through the resin-containing material. I found it higher than. That is, the inventor believes that the loss tangent of the material containing the resin at the temperature at which the glass transition occurs is higher than the crystallinity of the material containing the resin measured at room temperature, and the fluid permeability through the material containing the resin at room temperature. And has a high correlation.

  Based on the discovery of this inventor, by using the loss tangent of the resin-containing material at the α transition point of the resin-containing material as the loss tangent of the resin-containing material, the permeability of the fluid that passes through the resin-containing material is used. Can be evaluated more appropriately.

  In particular, since the loss tangent of the resin-containing material at the α transition point of the resin-containing material is an extreme value of the loss tangent of the resin-containing material with respect to the temperature of the resin-containing material, it is easier and more accurate. It is obtained by. That is, by using the loss tangent of the resin-containing material at the α transition point of the resin-containing material as the loss tangent of the resin-containing material, the permeability of the fluid that passes through the resin-containing material can be made easier and more It can be evaluated with high accuracy.

  In the first embodiment of the present invention, in the method for evaluating fluid permeability through a resin-containing material, preferably, the loss tangent of the resin-containing material at the α transition point of the resin-containing material is 0.2. Including determining whether or not: Here, the loss tangent of the resin-containing material at the α transition point of the resin-containing material is generally larger than zero. Since the α transition point of the resin-containing material is the glass transition point of the resin-containing material, the stress generated in the resin-containing material is generally not only the elastic component at the α-transition point of the resin-containing material. , Including its viscous components. Therefore, the loss tangent of the material including the resin at the α transition point of the material including the resin generally does not become zero.

  By determining whether the loss tangent of the resin-containing material at the α transition point of the resin-containing material is 0.2 or less, the permeability of the fluid that passes through the resin-containing material is within an allowable range. It is often possible to evaluate whether or not. That is, if the loss tangent of the resin-containing material at the α transition point of the resin-containing material exceeds 0.2, the permeability of the fluid that passes through the resin-containing material is too high, and the material containing the resin is In many cases, it is difficult to suppress the permeation of the permeating fluid. On the other hand, when the loss tangent of the resin-containing material at the α transition point of the resin-containing material is 0.2 or less, the permeability of the fluid that passes through the resin-containing material is within an allowable range, and the resin Suppression of fluid permeation through the material containing the resin by the containing material is often also appropriate.

  In the first embodiment of the present invention, in the method for evaluating fluid permeability through a resin-containing material, the loss tangent of the resin-containing material at the α transition point of the resin-containing material is preferably 0.16. Including determining whether or not: By determining whether the loss tangent of the resin-containing material at the α transition point of the resin-containing material is 0.16 or less, the permeation of the fluid that passes through the resin-containing material is sufficiently suppressed. It is often possible to evaluate whether or not. That is, when the loss tangent of the resin-containing material at the α transition point of the resin-containing material is 0.16 or less, the permeability of the fluid that passes through the resin-containing material is low and depends on the material containing the resin. In many cases, suppression of permeation of a fluid that permeates a material including a resin is also sufficient.

  In the first embodiment of the present invention, in the method for evaluating fluid permeability through a resin-containing material, the resin-containing material preferably contains a biodegradable resin. In this case, the permeability of the fluid that permeates the material containing the biodegradable resin can be more appropriately evaluated using the loss tangent of the material containing the biodegradable resin.

  In the first embodiment of the present invention, the biodegradable resin preferably includes polylactic acid in the method for evaluating fluid permeability through a resin-containing material. In this case, the permeability of the fluid that permeates the material containing polylactic acid can be more appropriately evaluated using the loss tangent of the material containing polylactic acid.

In particular, by determining whether the loss tangent of the material containing polylactic acid at the α transition point of the material containing polylactic acid is 0.2 or less, the permeability of the fluid that passes through the material containing polylactic acid is reduced. It can be evaluated whether it is within the allowable range. For example, whether or not the permeability of oxygen that permeates a material containing polylactic acid is approximately 120 ml · mm ⁻¹ · m ⁻² · MPa ⁻¹ · day− ¹ or less, and permeates the material that contains polylactic acid. It is possible to evaluate whether or not the moisture transmission rate is 18% or less in terms of 3 years. Further, by determining whether or not the loss tangent of the material containing polylactic acid at the α transition point of the material containing polylactic acid is 0.16 or less, the permeation of the fluid that passes through the material containing polylactic acid is It can be evaluated whether or not it is sufficiently suppressed. For example, the permeability of oxygen that permeates the material containing polylactic acid is approximately 40 ml · mm ⁻¹ · m ⁻² · MPa ⁻¹ · day− ¹ or less, and the material that contains polylactic acid permeates. It is possible to evaluate whether or not the moisture transmission rate is 10% or less in terms of 3 years. In addition, the permeability of oxygen that permeates the material containing polylactic acid per unit area (1 m ² ) and unit thickness (1 mm) when oxygen is applied to the sheet of material containing polylactic acid at a pressure of 1 MPa for one day. The volume (ml) of oxygen that permeates the sheet of material containing polylactic acid. In addition, the permeability of water that permeates the material containing polylactic acid is the ratio of the water that permeates out of the bottle in 3 years (%) when filling a bottle with an internal volume of 130 ml containing polylactic acid and a thickness of 1.1 mm. ).

  According to a second embodiment of the present invention, in the method for treating a material containing a biodegradable resin, the material containing the biodegradable resin is heated at a temperature of 90 ° C. or more and 140 ° C. or less for 5 minutes or more, preferably 30 minutes or more. It is characterized by doing.

  By heating the material containing the biodegradable resin at a temperature of 90 ° C. or higher and 140 ° C. or lower for 5 minutes or longer, preferably 30 minutes or longer, the material containing the heated biodegradable resin was heated at the α transition point. The loss tangent of the material containing the biodegradable resin can be made 0.2 or less. As a result, the permeability of the fluid that permeates the material containing the heated biodegradable resin is within an acceptable range, and the permeation of the fluid that permeates the material that contains the heated biodegradable resin is heated. The material containing the biodegradable resin can be more appropriately suppressed.

  Therefore, according to the second embodiment of the present invention, the material containing the biodegradable resin is heated at a temperature of 90 ° C. or higher and 140 ° C. or lower for 5 minutes or more, preferably 30 minutes or more. It is possible to provide a method for treating a material containing a biodegradable resin, which can more appropriately reduce the permeability of a fluid that permeates the containing material.

In the case where the treatment for heating the material containing the biodegradable resin is not performed, the loss tangent of the material containing the biodegradable resin at the α transition point of the material containing the biodegradable resin is approximately 1 or more. Further, for example, the oxygen permeability of a material containing a biodegradable resin that has not been heat-treated is about 200 ml · mm ⁻¹ · m ⁻² · MPa ⁻¹ · day− ¹ .

  In the method for treating a material containing a biodegradable resin according to the second embodiment of the present invention, preferably, the material containing the biodegradable resin is treated at a temperature of 120 ° C. or higher and 140 ° C. or lower for 5 minutes or more, preferably 30. Heat for more than a minute.

  By heating the material containing the biodegradable resin at a temperature of 120 ° C. or higher and 140 ° C. or lower for 5 minutes or longer, preferably 30 minutes or longer, the material containing the heated biodegradable resin was heated at the α transition point. The loss tangent of the material containing the biodegradable resin can be made to be 0.16 or less. As a result, the permeability of the fluid that permeates the material containing the heated biodegradable resin is lowered, and the permeation of the fluid that permeates the material that contains the heated biodegradable resin is reduced. It becomes possible to suppress sufficiently by the material containing.

In the method for treating a material containing a biodegradable resin according to the second embodiment of the present invention, preferably, the biodegradable resin contains polylactic acid. In this case, the material containing polylactic acid is heated at a temperature of 90 ° C. or higher and 140 ° C. or lower for 5 minutes or longer, preferably 30 minutes or longer, so that the heated polylactic acid-containing material is heated at the α transition point. The loss tangent of the material containing polylactic acid can be made 0.2 or less. Further, the permeability of oxygen permeable material comprising polylactic acid, generally ^{120ml · mm -1 · m -2 ·} MPa -1 · day ^-1, and the transmittance of the moisture transmitted through a material comprising polylactic acid Can be reduced to 18% or less in terms of 3 years. Furthermore, by heating the material containing polylactic acid at a temperature of 120 ° C. or higher and 140 ° C. or lower for 5 minutes or longer, preferably 30 minutes or longer, the heated polylactic acid at the α transition point of the heated polylactic acid-containing material. The loss tangent of the material containing can be made to be 0.16 or less. Further, the permeability of oxygen permeable material comprising polylactic acid, generally ^{40ml · mm -1 · m -2 ·} MPa -1 · day ^-1, and the transmittance of the moisture transmitted through a material comprising polylactic acid Can be reduced to 10% or less in terms of 3 years.

  The third embodiment of the present invention is a material containing a biodegradable resin, and the loss tangent of the material containing the biodegradable resin at the α transition point of the material containing the biodegradable resin is 0.2 or less. It is characterized by being.

  According to the third embodiment of the present invention, since the loss tangent of the material containing the biodegradable resin at the α transition point of the material containing the biodegradable resin is 0.2 or less, the permeability of the permeating fluid It is possible to provide a material containing a biodegradable resin in which is more appropriately reduced.

  In the material containing the biodegradable resin according to the third embodiment of the present invention, preferably, the loss tangent of the material containing the biodegradable resin at the α transition point of the material containing the biodegradable resin is 0.16 or less. It is. In this case, it is possible to provide a material containing a biodegradable resin in which the permeability of the permeating fluid is more effectively reduced.

In the material containing the biodegradable resin according to the third embodiment of the present invention, preferably, the biodegradable resin contains polylactic acid. In this case, a material containing polylactic acid in which the permeability of the permeating fluid is more appropriately reduced can be provided more reliably. For example, when the loss tangent of the material containing polylactic acid at the α transition point of the material containing polylactic acid is 0.2 or less, the permeability of oxygen that passes through the material containing polylactic acid is approximately 120 ml · mm ^−1. · ^m -2 · ^{MPa -1} · day ^-1 or less either, and the transmittance of the moisture transmitted through a material comprising polylactic acid may be 18% or less in 3 years terms. Further, when the loss tangent of the polylactic acid-containing material at the α transition point of the polylactic acid-containing material is 0.16 or less, the permeability of oxygen passing through the polylactic acid-containing material is approximately 40 ml · mm ^−1. · ^m -2 · ^{MPa -1} · day ^-1 or less either, and the transmittance of the moisture transmitted through a material comprising polylactic acid may be less than 10% in three years terms.

  According to a fourth embodiment of the present invention, in the material containing the biodegradable resin, the material containing the biodegradable resin is heated at a temperature of 90 ° C. or higher and 140 ° C. or lower for 5 minutes or longer, preferably 30 minutes or longer. It is characterized by being obtained.

  According to the fourth embodiment of the present invention, the material containing the biodegradable resin heats the material containing the biodegradable resin at a temperature of 90 ° C. or higher and 140 ° C. or lower for 5 minutes or more, preferably 30 minutes or more. Therefore, it is possible to provide a material containing a biodegradable resin in which the permeability of the fluid to be permeated is more appropriately reduced.

  In the material containing the biodegradable resin according to the fourth embodiment of the present invention, the material containing the biodegradable resin is preferably a material containing the biodegradable resin at a temperature of 120 ° C. or higher and 140 ° C. or lower. It is obtained by heating for 30 minutes or more, preferably 30 minutes or more. In this case, it is possible to provide a material containing a biodegradable resin in which the permeability of the permeating fluid is more effectively reduced.

In the material containing the biodegradable resin according to the fourth embodiment of the present invention, preferably, the biodegradable resin contains polylactic acid. In this case, a material containing polylactic acid in which the permeability of the permeating fluid is more appropriately reduced can be provided more reliably. For example, when the material containing polylactic acid is obtained by heating the material containing polylactic acid at a temperature of 90 ° C. or higher and 140 ° C. or lower for 5 minutes or longer, preferably 30 minutes or longer, the material containing polylactic acid is transmitted. The oxygen permeability is approximately 120 ml · mm ⁻¹ · m ⁻² · MPa ⁻¹ · day ⁻¹ or less, and the moisture permeability that permeates the material containing polylactic acid is 18 in terms of 3 years. % Or less. Furthermore, when the material containing polylactic acid is obtained by heating the material containing polylactic acid at a temperature of 120 ° C. or higher and 140 ° C. or lower for 5 minutes or more, the permeability of oxygen that passes through the material containing polylactic acid is: It is approximately 40 ml · mm ⁻¹ · m ⁻² · MPa ⁻¹ · day ⁻¹ or less, and the moisture permeability that permeates the material containing polylactic acid may be 10% or less in terms of 3 years.

  The fifth embodiment of the present invention is obtained by molding a material containing the biodegradable resin according to the third aspect of the present invention or the fourth embodiment of the present invention in a biodegradable resin molded body. It is characterized by. The material containing the biodegradable resin is molded by a known molding method such as injection molding, blow molding, extrusion molding, vacuum molding, pressure molding, and inflation molding. The biodegradable resin molded product is not particularly limited, and can be widely used as a consumer product including a cosmetic container.

  According to the fifth embodiment of the present invention, the biodegradable resin molded body is obtained by molding a material containing the biodegradable resin according to the third aspect of the present invention or the fourth embodiment of the present invention. Therefore, it is possible to provide a biodegradable resin molded body in which the permeability of the permeating fluid is more appropriately reduced.

(1) Preparation of polylactic acid resin composition As shown in Table 1, a composition obtained by dispersing an organically modified clay mineral in polylactic acid (average molecular weight: 160,000, melting point: 170 ° C., Nature Works 4032DK) A sheet was obtained by press molding under the conditions of a temperature of 195 ° C. and a pressure of 10 MPa. The dimensions of this sheet were 5 mm (width) × 35 mm (length) × 1.0 mm (thickness). Sheets prepared from the above polylactic acid compositions were heated for 5 minutes, 30 minutes, and 90 minutes under conditions of a pressure of 3 MPa and a temperature of 90 ° C. to obtain Samples 1, 2, and 3, respectively. Samples 4, 5, and 6 were obtained by heating for 5 minutes, 30 minutes, and 90 minutes, respectively, under conditions of a pressure of 3 MPa and a temperature of 120 ° C. Moreover, it heated for 5 minutes, 30 minutes, and 90 minutes on the conditions of the pressure of 3 Mpa, and the temperature of 140 degreeC, and obtained the samples 7, 8, and 9, respectively. In addition, in order to improve the gas barrier property of polylactic acid that prevents permeation of oxygen through polylactic acid, the organically modified clay mineral dispersed in polylactic acid is compared with synthetic fluorine mica (ME-100 manufactured by Co-op Chemical). It was an organically modified clay mineral added with 25% by weight of dodecylmethyldihydroxyethylammonium.

（２）試料の酸素透過度の測定
上記のようにして得られた試料１〜９のシートについての酸素透過度を測定した。試料１〜９のシートについての酸素透過度の測定には、ＭＯＣＯＮ社製の酸素ガス透過度測定装置ＯＸ−ＴＲＡＮ２／２０を使用した。なお、試料１〜９のシートの酸素透過度は、２５℃の温度、５０％の相対湿度、及び１ＭＰａの圧力の条件下で、試料１〜９のシートに酸素を１日間適用して、測定した。ここで、試料のシートの酸素透過度は、試料のシートに１日間１ＭＰａの圧力で酸素を適用したとき、単位面積（１ｍ^２）及び単位厚さ（１ｍｍ）当たりの試料のシートを透過する酸素の体積（ｍｌ）を表す。得られた試料１〜９のシートの酸素透過度（ｍｌ・ｍｍ^−１・ｍ^−２・ＭＰａ^−１・日^−１）を表２に示す。

(2) Measurement of oxygen permeability of sample The oxygen permeability of the sheets of Samples 1 to 9 obtained as described above was measured. An oxygen gas permeability measuring device OX-TRAN 2/20 manufactured by MOCON was used for measuring the oxygen permeability of the sheets of Samples 1 to 9. The oxygen permeability of the sheets of samples 1 to 9 was measured by applying oxygen to the sheets of samples 1 to 9 for one day under the conditions of a temperature of 25 ° C., a relative humidity of 50%, and a pressure of 1 MPa. did. Here, the oxygen permeability of the sample sheet is defined as oxygen permeating the sample sheet per unit area (1 m ² ) and unit thickness (1 mm) when oxygen is applied to the sample sheet at a pressure of 1 MPa for one day. Represents the volume (ml). Table 2 shows the oxygen permeability (ml · mm ⁻¹ · m ⁻² · MPa ⁻¹ · day ⁻¹ ) of the obtained sheets of Samples 1 to 9.

表２に示すように、ポリ乳酸組成物から作製したシートを加熱する温度及び時間によって、試料１〜９のシートの酸素透過度が異なることがわかった。

As shown in Table 2, it was found that the oxygen permeability of the sheets of Samples 1 to 9 was different depending on the temperature and time for heating the sheet prepared from the polylactic acid composition.

(3) was measured loss tangent tan [delta _max at α transition point of the sheet of the loss tangent tan [delta _max sample 1-9 obtained as the above measurement of the α transition point of the sample. A viscoelasticity measuring device (TA Instruments, ARES) was used to measure the loss tangent tan δ _max at the α transition point of the sheets of Samples 1 to 9. In the measurement of the loss tangent tan δ _max for the sheets of Samples 1 to 9, torsional strain in the range of ± 0.05% was given to the sheets of Samples 1 to 9 at a frequency of 1 Hz. Moreover, the temperature of the sheet | seat of the samples 1-9 was increased every 5 degreeC from -50 degreeC to 150 degreeC. Thus, the loss tangent tan δ for the sheets of Samples 1 to 9 at each temperature was measured, and the temperature dependence curve of the loss tangent tan δ for the sheets of Samples 1 to 9 was measured. The temperature at which the temperature dependence curve of the loss tangent tan δ for the obtained sheets of the samples 1 to 9 becomes a maximum is the α transition point, and the temperature dependence of the loss tangent tan δ for the obtained sheets of the samples 1 to 9 The maximum value in the sex curve was defined as the loss tangent tan δ _max at the α transition point. Table 3 shows loss tangent tan δ _max at the α transition point of the obtained sheets of Samples 1 to 9.

図１は、試料のシート１〜９についてのα転移点における損失正接ｔａｎδ_ｍａｘ及び酸素透過度の関係を示す図である。図１の横軸は、試料のシート１〜９についてのα転移点における損失正接ｔａｎδ_ｍａｘを表し、図１の縦軸は、試料のシート１〜９についての酸素透過度（ｍｌ・ｍｍ^−１・ｍ^−２・ＭＰａ^−１・日^−１）の値を示す。

FIG. 1 is a graph showing the relationship between the loss tangent tan δ _max and the oxygen permeability at the α transition point for the sheets 1 to 9 of the sample. The horizontal axis in FIG. 1 represents the loss tangent tan δ _max at the α transition point for the sample sheets 1 to 9, and the vertical axis in FIG. 1 represents the oxygen permeability (ml · mm ⁻¹⁾ for the sample sheets 1 to 9. -The ^{value of} m- ² * MPa- ¹ * day- ¹ ) is shown.

As shown in FIG. 1, the smaller the loss tangent tan δ _{max at} the α transition point for the sample sheets 1 to 9, the smaller the oxygen permeability for the sample sheets 1 to 9. The square R ² of the correlation coefficient between the loss tangent tan δ _max and the oxygen permeability at the α transition point for the sample sheets 1 to 9 is 0.63, and the α transition point for the sample sheets 1 to 9 The correlation between the loss tangent tan δ _max and the oxygen permeability was high. Therefore, it was confirmed that the oxygen permeability of the material containing polylactic acid can be appropriately evaluated by the loss tangent tan δ _{max at} the α transition point of the material containing polylactic acid.

Further, as shown in FIG. 1, when the loss tangent tan δ _{max at} the α transition point for the sample sheets 1 to 9 is 0.2 or less, the oxygen permeability for the sample sheets 1 to 9 is 120 ml · mm. ^-M - ² * MPa- ¹ * day- ¹ or less. That is, when the loss tangent tan δ _{max at} the α transition point of the material containing polylactic acid is 0.2 or less, the oxygen permeability of the material containing polylactic acid is 120 ml · mm · m ⁻² · MPa ⁻¹ · day. ^-1 or less was confirmed.

Furthermore, as shown in FIG. 1, when the loss tangent tan δ _{max at} the α transition point for the sample sheets 1 to 9 is 0.16 or less, the oxygen permeability for the sample sheets 1 to 9 is approximately 40 ml · mm · m ⁻² · MPa ⁻¹ · day− ¹ or less. That is, when the loss tangent tan δ _{max at} the α transition point of the material containing polylactic acid is 0.16 or less, the oxygen permeability of the material containing polylactic acid is approximately 40 ml · mm · m ⁻² · MPa ⁻¹ · It was confirmed that it was below day- ¹ .

(4) Measurement of crystallinity of sample The crystallinity of the sheets of Samples 1 to 9 obtained as described above was measured. An X-ray diffractometer (JDX-350, JOEL) using CuKα rays was used to measure the crystallinity of the sheets of Samples 1 to 9. About the sheet | seat of the samples 1-9, the X-ray-diffraction pattern in the range whose angle between the direction of the X-ray which injects into a sample and the direction of the angle of the X-ray diffracted by a sample is 5 degrees-30 degrees was obtained. In the X-ray diffraction patterns of the sheets of Samples 1 to 9, the angle between the X-ray direction incident on the sample and the X-ray angle direction diffracted by the sample is in the vicinity of 16 ° with a narrow width overlapping each other. Peaks and broad peaks were obtained. The narrow-width peak and the wide-width peak that are overlapped with each other are separated by a known peak separation method, the narrow-width peak is designated as the peak of diffraction X-rays from the crystal part in the sample, and the broad-width peak is designated. Was designated as the peak of diffracted X-rays from the amorphous part of the sample. Then, the areas of the narrow peak and the wide peak separated from each other are calculated, and the crystallinity in the sample is calculated.
Crystallinity = (Narrow-width peak area) / {(Narrow-width peak area) + (Wide-width peak area)} × 100
It was calculated according to the formula of Table 4 shows the crystallinity of the obtained sheets of Samples 1-9.

図２は、試料のシート１〜９についての結晶化度及び酸素透過度の関係を示す図である。図２の横軸は、試料のシート１〜９についての結晶化度を表し、図２の縦軸は、試料のシート１〜９についての酸素透過度（ｍｌ・ｍｍ^−１・ｍ^−２・ＭＰａ^−１・日^−１）の値を示す。

FIG. 2 is a diagram showing the relationship between the crystallinity and oxygen permeability for sample sheets 1-9. 2 represents the crystallinity of the sample sheets 1 to 9, and the vertical axis of FIG. 2 represents the oxygen permeability (ml · mm ⁻¹ · m ⁻² · The value of MPa- ¹ * day- ¹ ) is shown.

  The correlation between the crystallinity and the oxygen permeability for the sample sheets 1 to 9 in FIG. 2 was hardly observed. Therefore, it was confirmed that it is inappropriate to evaluate the oxygen permeability of the material containing polylactic acid based on the crystallinity of the material containing polylactic acid.

(1) Preparation of polylactic acid resin composition A composition obtained by dispersing an organically modified clay mineral in polylactic acid (average molecular weight: 160,000, melting point: 170 ° C., Nature Works 4032DK) Using ASB Machine Co., Ltd., ASB-50TH), melting at a cylinder set temperature of 200 ° C., filling in a 10 ° C. mold, cooling for 10 seconds to obtain a 5 mm thick preform (bottomed barison). It was. After heating this preform with hot air of 120 ° C., it was put into a mold set at a temperature of 40 ° C. and blow-molded under conditions of pressure air of 3.5 MPa, with an internal volume of 130 ml and a thickness of 1.1 mm. A bottle as a sample was prepared.

  As shown in Table 5, the bottles were heated at 90 ° C. for 3 hours, 16 hours, and 48 hours to obtain Samples 10, 11, and 12, respectively. Similarly, the sample bottles were heated at 120 ° C. for 3 hours, 16 hours, and 48 hours to obtain Samples 13, 14, and 15, respectively. Moreover, the bottle used as a sample was heated on the conditions of the temperature of 140 degreeC for 3 hours, 16 hours, and 48 hours, and the samples 16, 17, and 18 were obtained, respectively.

（２）試料の水分透過率の測定
上記のようにして得られた試料１０〜１８のボトルについての水分透過率を測定した。試料１０〜１８のボトルにそれぞれ水を充填し、試料１０〜１８のボトルの重量を測定した後、温度２５℃及び相対湿度５０％の恒温槽内で２８日間静置し、静置後に再度試料１０〜１８のボトルの重量を測定することにより、試料１０〜１８のボトルの重量減少率を求めた。ここで、試料のボトルの水分透過率は、試料のボトルの２８日間の重量減少率を３９．１倍（≒３６５日×３年／２８日）することにより、３年換算水分透過率（％）として算出した。得られた試料１０〜１８のボトルの３年換算水分透過率（％）を表６に示す。

(2) Measurement of moisture permeability of sample The moisture permeability of the bottles of Samples 10 to 18 obtained as described above was measured. After filling each bottle of Samples 10-18 with water and measuring the weight of the bottles of Samples 10-18, they were allowed to stand in a constant temperature bath at a temperature of 25 ° C. and a relative humidity of 50% for 28 days. The weight reduction rate of the bottles of Samples 10 to 18 was determined by measuring the weights of the 10 to 18 bottles. Here, the moisture permeability of the sample bottle is obtained by multiplying the weight reduction rate of the sample bottle for 28 days by 39.1 times (≈365 days × 3 years / 28 days), and converted to a three-year equivalent moisture permeability (% ). Table 6 shows the water permeability (%) in terms of 3 years of the obtained bottles of Samples 10 to 18.

表６に示すように、ポリ乳酸を加熱する温度及び時間によって、熱処理されたポリ乳酸の水分透過率が異なることがわかった。

As shown in Table 6, it was found that the water permeability of the heat-treated polylactic acid differs depending on the temperature and time for heating the polylactic acid.

(3) was measured loss tangent tan [delta _max at α transition point of the bottle loss in α transition point of the sample tangent tan [delta _max of the measurement sample 10 to 18 obtained as described above. The measurement was performed by the method of Example 1 described above. Table 7 shows loss tangent tan δ _max at the α transition point of the obtained bottles of Samples 10 to 18.

図３は、試料のボトル１０〜１８についてのα転移点における損失正接ｔａｎδ_ｍａｘ及び３年換算水分透過率の関係を示す図である。図３の横軸は、試料のボトル１０〜１８についてのα転移点における損失正接ｔａｎδ_ｍａｘを表し、図３の縦軸は、試料のボトル１０〜１８についての３年換算水分透過率（％）の値を示す。

FIG. 3 is a graph showing the relationship between the loss tangent tan δ _{max at} the α transition point and the three-year equivalent water permeability for the bottles 10 to 18 of the sample. The horizontal axis in FIG. 3 represents the loss tangent tan δ _max at the α transition point for the sample bottles 10 to 18, and the vertical axis in FIG. 3 represents the three-year equivalent water permeability (%) for the sample bottles 10 to 18. Indicates the value of.

As shown in FIG. 3, the smaller the loss tangent tan δ _{max at} the α transition point for the sample bottles 10 to 18, the smaller the three-year equivalent water permeability for the sample bottles 10 to 18. Further, the square R ² of the correlation coefficient between the loss tangent tan δ _{max at} the α transition point and the three-year equivalent water permeability for the sample bottles 10 to 18 is 0.92, and the sample bottles 10 to 18 The correlation between the loss tangent tan δ _{max at the} α transition point and the three-year equivalent water permeability was very high. Therefore, it was confirmed that the water permeability of the material containing polylactic acid can be appropriately evaluated by the loss tangent tan δ _{max at} the α transition point of the material containing polylactic acid.

Also, as shown in FIG. 3, when the loss tangent tan δ _{max at} the α transition point for the sample bottles 10 to 18 is 0.2 or less, the three-year equivalent water permeability for the sample bottles 10 to 18 is 18% or less. That is, when the loss tangent tan δ _{max at} the α transition point of the material containing polylactic acid is 0.2 or less, it is confirmed that the three-year equivalent moisture permeability of the material containing polylactic acid is 18% or less. It was.

Furthermore, as shown in FIG. 3, when the loss tangent tan δ _{max at} the α transition point for the sample bottles 10 to 18 is 0.16 or less, the three-year moisture permeability for the sample bottles 10 to 18 is 10 % Or less. That is, it was confirmed that when the loss tangent tan δ _{max at} the α transition point of the material containing polylactic acid is 0.16 or less, the oxygen permeability of the material containing polylactic acid is 10% or less.

(4) Measurement of crystallinity of sample The crystallinity of the bottles of Samples 10 to 18 obtained as described above was measured. The measurement was performed by the method of Example 1 described above. Table 8 shows the crystallinity of the obtained bottles of Samples 10 to 18.

図４は、試料のボトル１０〜１８についての結晶化度及び３年換算水分透過率の関係を示す図である。図４の横軸は、試料のボトル１０〜１８についての結晶化度を表し、図４の縦軸は、試料のボトル１０〜１８についての３年換算水分透過率（％）の値を示す。

FIG. 4 is a diagram showing the relationship between the degree of crystallinity and the three-year equivalent water permeability for the sample bottles 10 to 18. The horizontal axis of FIG. 4 represents the degree of crystallinity of the sample bottles 10 to 18, and the vertical axis of FIG. 4 represents the value of the three-year equivalent moisture permeability (%) for the sample bottles 10 to 18.

The square R ² of the correlation coefficient between the crystallinity of the sample bottles 12 to 30 in FIG. 4 and the three-year equivalent water permeability is 0.58, and the crystallinity of the sample bottles 10 to 18 is Although the correlation with the 3-year equivalent water permeability was recognized to some extent, the correlation coefficient between the loss tangent tan δ _{max at} the α transition point and the 3-year equivalent moisture permeability shown in FIG. Was lower. Therefore, rather than evaluating the moisture permeability of the material containing polylactic acid according to the crystallinity of the material containing polylactic acid, the loss tangent tan δ _{max at} the α transition point of the material containing polylactic acid is used. It was confirmed that it is more appropriate to evaluate moisture permeability.

  Although the embodiments and examples of the present invention have been specifically described above, the present invention is not limited to these embodiments and examples, and these embodiments and examples of the present invention are not limited thereto. Can be changed or modified without departing from the spirit and scope of the present invention.

It is a figure which shows the relationship between the loss tangent tan-delta _max in the alpha transition point about the sheet | seats 1-9 of a sample, and oxygen permeability. It is a figure which shows the relationship between the crystallinity degree about the sheet | seats 1-9 of a sample, and oxygen permeability. It is a figure which shows the relationship between the loss tangent tan-delta _max in the alpha transition point about the bottles 10-18 of a sample, and a moisture permeability. It is a figure which shows the relationship between the crystallinity degree about the bottles 10-18 of a sample, and a moisture permeability.

Claims (11)

Evaluation of fluid permeability through a resin-containing material using loss tangent by dynamic viscoelasticity measurement of the resin-containing material to evaluate the permeability of the fluid that passes through the resin-containing material Method. The loss tangent of the material containing the resin by dynamic viscoelasticity measurement is the loss tangent of the material containing the resin at the phase transition point by dynamic viscoelasticity measurement of the material containing the resin. The evaluation method of the permeability | transmittance of the fluid through the material containing resin as described in 4. Loss tangent by dynamic viscoelasticity measurement of material containing resin at phase transition point of material containing resin is loss tangent by dynamic viscoelasticity measurement of material containing resin at α transition point of material containing resin The method for evaluating the permeability of a fluid through a material containing a resin according to claim 2. The method includes determining whether or not a loss tangent by dynamic viscoelasticity measurement of the material containing the resin at the α transition point of the material containing the resin is 0.2 or less. The evaluation method of the permeability | transmittance of the fluid through the material containing resin as described in 4. The method includes determining whether or not a loss tangent of the material containing the resin at the α transition point of the material containing the resin by a dynamic viscoelasticity measurement is 0.16 or less. The evaluation method of the permeability | transmittance of the fluid through the material containing resin as described in 4. The method for evaluating fluid permeability through a material containing a resin according to any one of claims 1 to 5, wherein the material containing the resin contains a biodegradable resin. The method of evaluating fluid permeability through a material containing a resin according to claim 6, wherein the biodegradable resin contains polylactic acid. The material containing the biodegradable resin is subjected to heat treatment at a temperature of 90 ° C or higher and 140 ° C or lower for 5 minutes or more, and evaluation of fluid permeability through the resin-containing material according to claim 6 or 7. Method. The method for evaluating fluid permeability through a material containing a resin according to claim 8, wherein the material containing the biodegradable resin is heat-treated at a temperature of 120 ° C. or more and 140 ° C. or less for 5 minutes or more. The method for evaluating fluid permeability through a material containing a resin according to claim 6 or 7, wherein the material containing the biodegradable resin is heat-treated at a temperature of 90 ° C or higher and 140 ° C or lower for 30 minutes or longer. . The method for evaluating fluid permeability through a material containing a resin according to claim 8, wherein the material containing the biodegradable resin is heat-treated at a temperature of 120 ° C. or higher and 140 ° C. or lower for 30 minutes or more.

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