JP2005205599A - Method and apparatus for evaluating characteristics of thermoplastic elastomer, processing condition setting method, extrusion discharge amount control device and processing control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To estimate the extrusion processability of a thermoplastic elastomer with high reliability and to manufacture an extrusion molded product of high quality under the optimum extrusion processing condition. <P>SOLUTION: This apparatus for evaluating the characteristics of the thermoplastic elastomer is equipped with a viscoelasticity measuring instrument 1 for controlling the shearing force applied to the thermoplastic elastomer by changing vibration frequency and vibration amplitude to measure viscoelastic characteristics, an Ea arithmetic device 4 for calculating the Ea value of the thermoplastic elastomer according to the operational expression : η=Aexp(Ea/RT) (wherein a temperature and a gas constant at the time of measurement are respectively T and R, viscosity is η*(η) and apparent activation energy is Ea) and a G*r arithmetic device 8 for calculating a change rate G*r of complex elastic modulus G* from the ratio of the complex elastic moduli of two shearing regions. The extrusion processability of the thermoplastic elastomer and the mechanical physical properties of the extrusion molded product are estimated on the basis of the operation values of Ea and G*r. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a technique for evaluating mechanical properties and processability of a molded article made of a thermoplastic elastomer composition, and more particularly to a property evaluation method and a property evaluation device including mechanical properties and processability, and to the associated devices. The present invention relates to a processing condition setting method, an extrusion discharge amount control device, and a processing management method for a thermoplastic elastomer composition.

  In many fields, including automotive parts, building parts, and home appliance parts, heat that is a soft member similar to rubber and that has the same moldability as a thermoplastic resin without requiring a separate vulcanization molding step. Plastic elastomers are attracting attention.

  In addition to styrene, there are many types of thermoplastic elastomers such as vinyl chloride, olefin, polyester, polyamide, and urethane, and any thermoplastic elastomer can be used as a raw material. Even if it is a product, its quality, performance and processability are known to be greatly affected by variations in compound kneading.

  For example, the properties of cross-linked thermoplastic elastomers are generally largely governed by the molecular properties of the matrix phase (resin), the molecular properties of the domain (rubber particle) phase, the degree of crosslinking, the particle size of the rubber particle phase, and its uniformity. It is thought that.

  Even with thermoplastic elastomers of the same formulation and processing conditions, for example, moderate cross-linking always occurs during dynamic heat treatment, and the matrix phase (resin component) and domain phase (rubber component) are uniformly in the same state. It does not always exist. This is because the compound kneading state varies due to slight differences in the processing environment. Further, the processing variation of the compound greatly affects the workability in the next process, and also has a large effect on the final product.

  In recent years, thermoplastic elastomers are considered to have more complex physical properties and flow mechanisms than vulcanized rubber or thermoplastic resin. Therefore, the morphology evaluation technology (kneading state evaluation technology) and processing There is a need for sex assessment methods.

  Especially in the molding process using thermoplastic elastomer as a raw material, there is an increasing demand for reducing the defect rate and increasing the material yield, while maintaining high physical properties and producing high-quality molded products under optimal molding conditions. Therefore, there is a need for a method that can accurately evaluate the physical properties and workability of materials.

In the evaluation of the processability of conventional general thermoplastic elastomers, melt flow rate (hereinafter referred to as MFR) (JIS K7120) is used. For example, in Patent Document 1, molding of an olefin-based thermoplastic elastomer composition is used. Workability is evaluated by MFR.
JP 2003-82023 A

  However, since the evaluation by MFR is a method for evaluating the discharge amount at a constant load, detailed information on the extrusion processability depending on the kneading state of the thermoplastic elastomer composition, for example, the kneading state of the material, the extrusion discharge stability It is difficult to accurately grasp the properties, the discharge amount variability, the suitability of the cross-sectional shape in profile extrusion, the surface appearance of the extruded product, and the like.

  In addition, the above-mentioned MFR value is also used as a substitute evaluation of the kneading state by using physical properties evaluation by measurement of hardness, tensile permanent strain, tensile strength, maximum elongation, etc., as described above. As long as it is based on the MFR value, it is impossible to grasp in detail the kneading state greatly related to the physical properties of the molded product.

  Furthermore, as other evaluation methods, for example, there are a gel content determination method and a physical property evaluation method by a cyclohexane insoluble content measurement method, but the measurement takes time, and it is insufficient as a material evaluation (inspection) method requiring immediate effect.

  The present invention has been made by paying attention to such problems. In particular, the mechanical properties and molding processability of thermoplastic elastomers can be predicted with high reliability and in a short time, and the quality can be improved under optimum molding process conditions. It is an object of the present invention to provide a characteristic evaluation method and apparatus, a processing condition setting method, an extrusion discharge amount control device, and a processing management method that can manufacture an extruded product having a high height.

  The invention according to claim 1 controls the shearing force applied to the thermoplastic elastomer kneaded under predetermined kneading conditions by changing the vibration frequency and vibration amplitude within a predetermined temperature range, and reacts to the shearing force. A measurement step for obtaining a complex viscosity η * (η) of the thermoplastic elastomer and a complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates, and a temperature at the time of the measurement An Arrhenius type equation (Andrade) representing the temperature dependence of viscoelastic materials, where T and R are the gas constants, η is the viscosity, η * (η) is the complex viscosity, and Ea is the apparent activation energy. The step of calculating the apparent activation energy Ea of the thermoplastic elastomer based on the formula (1) and the ratio of the two complex elastic moduli G * obtained previously And a step of calculating a rate of change G * r (abbreviation of G * rate) of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property.

η = Aexp (Ea / RT) (1)
However,
Ea: Abbreviation for Activation Energy, apparent activation energy of compound viscosity (flow) (× 10 ⁻¹ KJ / mol)
Based on the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G *, the mechanical properties and extrusion processability of the extruded product made of a thermoplastic elastomer are evaluated. It is characterized by that.

  In this case, as described in claim 2, for each of a plurality of thermoplastic elastomers having the same composition and different kneading conditions, the apparent activation energy Ea and the complex elastic modulus G * that can be molded in the extrusion process It is desirable to set the permissible range of each change rate G * r in advance.

  Further, as described in claim 3, the mechanical properties are at least the hardness, tensile strength, and maximum elongation of an extruded product made of a thermoplastic elastomer, and at the same time, the moldability is claimed in the claims. 4. Extrusion that allows at least the average extrusion discharge amount of the thermoplastic elastomer during extrusion molding, the discharge amount variation rate, the appearance appearance of the extrusion molded product, and the cross-sectional shape of the extrusion molded product to be within the intersection, as described in 4 The screw rotation speed of the machine and the cross-sectional shape of the extruded product are either good or bad.

  The invention according to claim 5 is a thermoplastic elastomer characterized in that the technique according to claim 1 is grasped as a characteristic evaluation device and has the following requirements (a1) to (e1). It is a characteristic evaluation device.

  (A1) By changing the vibration frequency and vibration amplitude within a predetermined temperature range to control the shear force applied to the thermoplastic elastomer kneaded under a predetermined kneading condition, based on the stress that reacts to the shear force, Measuring means for determining the complex viscosity η * (η) of the thermoplastic elastomer and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates.

  (B1) Equations representing the temperature dependence of the viscoelastic material, where T and R are the temperature and gas constant at the time of the measurement, the viscosity is η, the complex viscosity is η * (η), and the apparent activation energy is Ea. First computing means for calculating an apparent activation energy Ea of the thermoplastic elastomer based on (1).

  (C1) Second computing means for calculating a rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously.

  (D1) Allowance of apparent activation energy Ea and change rate G * r of complex elastic modulus G * that can be molded in the extrusion molding process for a plurality of thermoplastic elastomers having the same composition and different kneading conditions Storage means with a preset range.

  (E1) The apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated by the first and second arithmetic means, the activation energy Ea stored in the storage means, and A determination means for evaluating the mechanical properties and molding processability of an extrusion-molded product made of a thermoplastic elastomer by individually comparing each allowable range of the change rate G * r of the complex elastic modulus G *.

  Examples of the thermoplastic elastomer applicable to the above characteristic evaluation include olefins, styrenes, urethanes, polyesters, vinyl chloride resins, polyamides, etc. A combination of a plurality of types may be used. Furthermore, as a crosslinked form, it is applicable to thermoplastic elastomers having a known structure such as a crosslinked type, a non-crosslinked type (simple blend type in which crosslinking is not performed), and a copolymerized type.

  As a matter of course, as the thermoplastic elastomer, those in which components according to various purposes are blended in addition to the matrix component are also applicable. Examples of components according to various purposes include foaming agents (including commonly used foaming agents, thermal expansion microcapsules, water-containing microcapsules, etc.), foaming aids, antioxidants, anti-aging agents, and heat stability. Agent, light stabilizer, ultraviolet absorber, neutralizer, lubricant, anti-fogging agent, anti-blocking agent, slip agent, dispersant, flame retardant, antistatic agent, conductivity-imparting agent, tackifier, cross-linking agent, cross-linking Auxiliaries, metal deactivators, molecular weight regulators, antibacterial / antifungal agents, fluorescent brighteners, sliding improvers, colorants such as carbon black and titanium oxide, metal powders such as ferrite, glass fibers, metals Inorganic fibers such as fibers, organic fibers such as carbon fibers and aramid fibers, composite fibers, glass balloons, glass flakes, asbestos, mica, calcium carbonate, talc, silica, calcium silicate, hydrotalcite, kao Emissions, clay, graphite, carbon nanotubes, fullerene, barium sulfate, fluororesin, filler such as polymer beads, a polyolefin wax, cellulose powder, rubber powder, regenerated rubber, a low molecular weight polymer and the like.

  The apparent activation energy Ea has a strong influence on the degree of dynamic cross-linking because it has a correlation with material properties such as strength and permanent set, in addition to cyclohexane insoluble components, especially in dynamically cross-linked thermoplastic elastomers. Conceivable. Therefore, the apparent activation energy Ea is considered to be an index for predicting mechanical properties and proved to be effective as a material management index.

  That is, in the thermoplastic elastomer of the same composition, the degree of progress of the dynamic cross-linking degree greatly affects the mechanical properties such as hardness, tensile set, tensile strength, maximum elongation, and the apparent activation energy Ea is This is a measure for evaluating the mechanical properties of extruded products made of thermoplastic elastomer.

  When the apparent activation energy Ea decreases, the degree of dynamic crosslinking increases, and therefore mechanical properties such as tensile set and tensile strength are improved. However, when the apparent activation energy Ea is too small, it indicates that the crosslinking is locally concentrated, and the surface appearance of the extrusion-molded product is deteriorated (occurrence of a so-called cross-linked gel called soot). .

  At the same time, the apparent activation energy Ea becomes a scale for evaluating the variation in the extrusion discharge amount of the thermoplastic elastomer. When the apparent activation energy Ea is large, the discharge amount variation is large, and conversely, when the apparent activation energy Ea is small, the discharge amount variation is small.

  That is, in the extrusion process, the material is transported by a screw in the process of moving in the order of feed zone → cylinder → head → base. In the process, various temperature histories are received from the charging of materials to the discharging. Therefore, a material that is easily affected by a viscosity due to a temperature change (a material having a large Ea) is likely to change in fluidity, and thus the extrusion fluidity is likely to vary due to a slight difference in the extrusion environment. This phenomenon occurs in the same way in the crosslinked type and the non-crosslinked type.

  For this reason, in the extrusion processability, when the apparent activation energy Ea is increased, the variation of the extrusion discharge amount is increased, and when the apparent activation energy Ea is too small, the crosslinking reaction is locally concentrated. As a result, it was found that the surface appearance of the extrusion-molded product was deteriorated and so-called blisters tend to occur. Therefore, by measuring the apparent activation energy Ea of the thermoplastic elastomer, the extrudability and mechanical properties can be evaluated.

  The change rate G * r of the complex elastic modulus G * indicates the dependence of the complex elastic modulus G * on the shear rate, and is obtained by quantifying it. In particular, since it is consistent with the form of the dispersed phase and the degree of phase separation in the electron microscope observation, the change rate G * r of the complex elastic modulus G * is considered to reflect the form of the dispersed phase and the degree of phase separation. It is done. When the degree of phase separation is poor, the change rate G * r of the complex elastic modulus G * tends to be low, and the surface gloss of the material is deteriorated due to the correlation with it, which is effective in managing the surface appearance.

  In general, for example, the gloss of a crosslinked type thermoplastic elastomer is likely to change due to a difference in morphology, and it was not easy to control it, but the change in the apparent activation energy Ea and complex elastic modulus G * By providing a management range for the rate G * r and controlling kneading, it is possible to determine a material with a stable gloss.

  That is, the rate of change G * r of the complex elastic modulus G * is a scale that represents the composite structure of a rubber-resin viscoelastic material. Therefore, the mechanical properties of the thermoplastic elastomer, that is, hardness, tensile set, tensile strength There is a correlation with the maximum elongation, etc., and its evaluation is also possible.

  On the other hand, when paying attention to the kneading state at the time of manufacturing the thermoplastic elastomer, for example, in the case of a dynamic cross-linking type thermoplastic elastomer, it is desirable that the cross-linking reaction proceeds after the rubber and the resin component are uniformly dispersed to some extent. The dynamic crosslinking treatment of the rubber has implications for immobilizing a structure in which the rubber is highly dispersed in a fine particle size in the olefin resin matrix, in addition to enhancing the properties of the rubber itself. For this reason, forming a stable morphology by taking a certain distance between dispersion and cross-linking is an important factor in formulation design.

  However, due to variations in the processing environment at the time of kneading, the timing of dispersion and crosslinking is not necessarily constant, and even if kneading is performed under the same conditions, it is common that a certain degree of variation occurs in the morphology.

  Accordingly, the uniformity and degree of crosslinking of the matrix phase (resin component) and domain phase (rubber component) of the dynamic cross-linking type thermoplastic elastomer also vary, and the matrix phase of the non-crosslinking type thermoplastic elastomer, etc. As a result, variations in the uniformity of the domain phase occur.

  Therefore, the evaluation of the kneading state at the time of manufacturing such a thermoplastic elastomer is also performed with the Ea value and the G * r value. That is, as described above, if both the Ea value and the G * r value are within the predetermined control range (setting range), it can be determined that the material is excellent in quality and excellent in extrudability. . This is because the morphology of the thermoplastic elastomer can be evaluated by both the Ea value and the G * r value, and as a result, the physical properties and extrusion processability of the material can be evaluated and managed. The detailed evaluation of the kneading state described can be performed simultaneously.

  The invention described in claim 6 includes the following steps (a2) to (d2) as a processing condition setting method for the thermoplastic elastomer based on the technique described in claim 1.

  (A2) By changing the vibration frequency and vibration amplitude in a predetermined temperature range to control the shear force applied to the thermoplastic elastomer kneaded under a predetermined kneading condition, based on the stress that reacts to the shear force, A measurement step for determining the complex viscosity η * (η) of the thermoplastic elastomer and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates.

  (B2) Equation representing the temperature dependence of the viscoelastic material, where T and R are the temperature and gas constant at the time of measurement, the viscosity is η, the complex viscosity is η * (η), and the apparent activation energy is Ea. A step of calculating an apparent activation energy Ea of the thermoplastic elastomer based on (1).

  (C2) A step of calculating a rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously.

  (D2) The apparent activation energy Ea previously obtained on the correlation data in which the correlation between the allowable width of the apparent activation energy Ea and the allowable width of the change rate G * r of the complex elastic modulus G * is predetermined. When the measured point position is designated with the value of the change rate G * r of the complex elastic modulus G *, the relative positional relationship between the intermediate point of the allowable width on the correlation data and the measured point position is set as the radial rate M. The process of calculating.

  The extrusion conditions for the thermoplastic elastomer are set based on the values of the apparent activation energy Ea, the change rate G * r of the complex elastic modulus G *, and the radial modulus M calculated in advance. To do.

  The dynamic system rate M will be described later.

  In this case, as set forth in claim 7, prior to setting the extrusion conditions of the thermoplastic elastomer, the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated previously are The extrudability of an extruded product made of a thermoplastic elastomer is compared by individually comparing the allowable ranges of the activation energy Ea and the change rate G * r of the complex elastic modulus G *. It is desirable to include a determination step for performing evaluation.

  In addition, as described in claim 8, each of the cases where extrusion molding is performed under specific extrusion processing conditions using a plurality of thermoplastic elastomers having the same composition and different kneading conditions is molded in the extrusion molding process. It is desirable that the allowable ranges of the possible apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * are set in advance.

  More preferably, as described in claim 9, on the condition that the evaluation result of the molding processability in the determination step is good, the allowable width of the apparent activation energy Ea and the change in the complex elastic modulus G * Specify the measurement point position with the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated on the correlation data in which the correlation with the allowable range of the rate G * r is predetermined. In this case, the step of calculating the relative positional relationship between the intermediate point of the allowable width on the correlation data and the position of the actual measurement point as the radial rate M, and based on the radial rate M, a specific extruded product is obtained. For the discharge amount calculation step for calculating the extrusion discharge amount of the thermoplastic elastomer suitable for extrusion molding, and for the extrusion molded product determined to have good extrudability by the determination means, the discharge amount calculation step is first performed. To the extrusion discharge amount calculated by It is desirable to Zui and a step of setting the extrusion processing conditions of the extruded product.

  In this case, as set forth in claim 10, in the step of setting the extrusion processing conditions, the correlation data between the preset radial velocity M and the screw rotation speed of the extruder, and the previously calculated radial velocity. It is assumed that the screw rotational speed corresponding to the calculated radial rate M is calculated by comparing with M.

  The invention according to an eleventh aspect captures the technique according to the sixth aspect as an extrusion discharge amount control device for a thermoplastic elastomer, and includes the following means (a3) to (h3). is there.

  (A3) By changing the vibration frequency and vibration amplitude within a predetermined temperature range to control the shear force applied to the thermoplastic elastomer kneaded under a predetermined kneading condition, based on the stress that reacts to the shear force, Measuring means for determining the complex viscosity η * (η) of the thermoplastic elastomer and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates.

  (B3) Equation representing the temperature dependence of the viscoelastic material, where T and R are the temperature and gas constant at the time of the measurement, the viscosity is η, the complex viscosity is η * (η), and the apparent activation energy is Ea. First computing means for calculating an apparent activation energy Ea of the thermoplastic elastomer based on (1).

  (C3) Second computing means for calculating the rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously.

  (D3) The apparent activation energy Ea previously calculated on the correlation data in which the correlation between the allowable width of the apparent activation energy Ea and the allowable width of the change rate G * r of the complex elastic modulus G * is predetermined. When the measured point position is designated with the value of the change rate G * r of the complex elastic modulus G *, the relative positional relationship between the intermediate point of the allowable width on the correlation data and the measured point position is set as the radial rate M. Third calculating means for calculating.

  (E3) Apparent activation energy Ea that can be molded in the extrusion process for each of the cases where extrusion molding is performed under specific extrusion conditions using a plurality of thermoplastic elastomers having the same composition and different kneading conditions And storage means in which the permissible ranges of the rate of change G * r of the complex elastic modulus G * are preset.

  (F3) The values of the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated by the first and second calculation means, the activation energy Ea stored in the storage means, and A determination means for evaluating the extrudability of an extruded product made of a thermoplastic elastomer by individually comparing each allowable range of the change rate G * r of the complex elastic modulus G *.

  (G3) Discharge amount calculating means for calculating an extrusion discharge amount of a thermoplastic elastomer suitable for extruding a specific extruded product based on the radial ratio M calculated by the third calculating means.

  (H3) Condition setting for setting the extrusion processing conditions of the extrusion-molded product based on the extrusion discharge amount calculated by the discharge amount calculation unit for the extrusion-molded product determined to have good extrudability by the determination unit means.

  In this case, as described in claim 12, the discharge amount calculating means includes the correlation data between the preset radial velocity M and the screw rotation speed of the extruder, and the previously calculated radial velocity M and And the above condition setting means gives the screw speed calculated earlier prior to the start of extrusion molding by the extruder to the extruder, while calculating the screw speed corresponding to the calculated radial rate M. It is supposed to be.

  Furthermore, the invention described in claim 13 captures the technique described in claim 6 as a process management method for a thermoplastic elastomer, and includes the following steps (a4) to (f4). .

  (A4) By changing the vibration frequency and vibration amplitude in a predetermined temperature range to control the shear force applied to the thermoplastic elastomer kneaded under a predetermined kneading condition, based on the stress that reacts to the shear force, A measurement step for determining the complex viscosity η * (η) of the thermoplastic elastomer and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates.

  (B4) The temperature and gas constants at the time of the above measurement are T and R, the viscosity is η, the complex viscosity is η * (η), the apparent activation energy is Ea, and the equation representing the temperature dependence of the viscoelastic material. A step of calculating an apparent activation energy Ea of the thermoplastic elastomer based on (1).

  (C4) A step of calculating a rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously.

  (D4) The apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated previously, and the preset change rate G * r of the activation energy Ea and the complex elastic modulus G * The determination process which evaluates the extrudability of the extrusion molded product which uses a thermoplastic elastomer as a raw material by comparing each of the allowable ranges individually.

  (E4) Correlation between the allowable width of the apparent activation energy Ea and the allowable width of the change rate G * r of the complex elastic modulus G * on condition that the evaluation result of the extrudability in the determination step is good. Is specified on the correlation data, when the measured point position is designated with the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * obtained previously, A step of calculating a relative positional relationship between the intermediate point of the allowable width and the measured point position as the radial rate M.

  (F4) A discharge amount calculation step of calculating an extrusion discharge amount of a thermoplastic elastomer suitable for extrusion molding a specific extrusion-molded product based on the moving radius ratio M.

  And while controlling an extruder so that it may become the extrusion discharge amount computed at the said discharge amount calculation process, when it determines with the shaping | molding process impossible at the said determination process, it changes the kneading | mixing conditions of a thermoplastic elastomer. It is characterized by.

  In this case, as described in claim 14, in the discharge amount calculating step, correlation data between a preset radial velocity M and the screw rotation speed of the extruder, and the previously calculated radial velocity M and And the number of screw rotations corresponding to the calculated radial rate M is calculated.

  More specifically, the dynamic system rate M in the inventions according to claims 6 to 14 is defined as follows. That is, for example, one of the values of the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * is designated as Ea in which the allowable width of one value is specified on the horizontal axis and the allowable width of the other value is specified on the horizontal axis. When an arbitrary point is plotted on the -G * r characteristic diagram, the distance between the intermediate point of the allowable area on the Ea-G * r characteristic diagram and the origin, and the distance between the arbitrary point and the origin Is defined as the dynamic rate M.

  It has been mentioned above that the internal structure of the thermoplastic elastomer can be positioned from both the apparent activation energy Ea and the rate of change G * r of the complex elastic modulus G *. From this, it is considered that the extrusion discharge amount can also be predicted from the relationship between both the Ea value and the G * r value correlated with the internal structure, and the radial rate calculated from both the Ea value and the G * r value. An index called M was defined. As a result, it is possible to determine whether or not the cross-sectional shape of the extrusion-molded product can be accurately extruded at the time of extrusion molding with the radial rate M derived from both the Ea value and the G * r value. It is possible to predict the extrusion discharge amount variability during extrusion molding, the surface appearance of the extrusion molded product, and the extrusion discharge amount. At the same time, since the M value, which is the radial rate, has a correlation with the extrusion discharge amount, it has been found that it is effective in predicting the screw rotation speed of the extruder.

  Thus, by using each value of Ea, G * r, and M as a predicted value of the extrusion processability of a thermoplastic elastomer, it is possible to produce a high-quality extruded product under optimum molding conditions. Become.

  According to the first to fifth aspects of the invention, in addition to mechanical properties such as hardness, tensile strength, and maximum elongation of an extruded product made of a thermoplastic elastomer, at least the average extrusion of the thermoplastic elastomer at the time of extrusion molding. Extrusion processability such as discharge rate, discharge rate variation rate, appearance appearance of extruded products, screw speed of extruder and cross-sectional shape of extruded products can be accurately predicted and evaluated with high reliability. It can contribute to the improvement of productivity and the quality improvement of the extruded product.

  Moreover, according to invention of Claims 6-14, the extrusion process conditions at the time of extruding the extrusion molded article which uses a thermoplastic elastomer as a raw material, ie, an extrusion discharge amount and the screw rotation speed of an extruder, are optimal values. Therefore, it is possible to contribute to the improvement of productivity and the quality of extruded products.

  Tables 1 and 2 show the results of the evaluation of the properties of a plurality of samples a to j of the thermoplastic elastomer having the same blending but different kneading conditions, that is, the extrusion processability and the mechanical properties, which are molding processability. Show.

  The material composition of each sample aj in Table 1 was made common at the following ratio.

(1) EPDM (ethylene / propylene / 5-ethylidene-2-norbornene three-dimensional copolymer) which is an olefin elastomer
: 100 phr
(2) PP (polypropylene): 70 phr
(3) Zinc stearate: 5 phr
(4) Paraffinic mineral oil: 60 phr
(5) Carbon black (FEF): 10 phr
(6) 2.5 dimethyl-2.5-di- (tert-butylperoxy) hexane as a crosslinking agent: 3 phr
(7) Divinylbenzene as a crosslinking aid: 1 phr
For sample preparation, the blended materials (1) to (5) above were put into a 0.6 L Banbury mixer and kneaded at a rotation speed of 50 to 100 rpm and a temperature of 190 ° C. as shown in Table 3, and then the largest side was Pelletized into 3-5 mm dice. Next, the above-mentioned materials (6) and (7) are blended into these pellets, that is, a solution in which the crosslinking agent (6) and the crosslinking assistant (7) are melt-dispersed is added, and the same direction rotating type Dynamic heat treatment was performed at a screw speed and temperature shown in Table 3 using a twin-screw extruder. Further, the obtained compound was pelletized to obtain thermoplastic elastomer samples a to j. Samples a to j were subjected to extrusion evaluation after being sufficiently dried.

  The dynamic heat treatment is a method of performing heat treatment while applying a shearing force, and a batch type or continuous type kneading apparatus such as a continuous type can be used. For example, open-type mixing rolls, closed-type mixers, batch-type melt-type kneaders such as kneaders, single-screw extruders, co-rotating continuous twin-screw extruders, counter-rotating continuous twin-screw extruders Etc. are the typical ones.

  In the columns of viscoelasticity of samples a to j in Tables 1 and 2, the apparent activation energy Ea, the change rate G * r of the complex elastic modulus G *, and the radial rate M are obtained as measurement results obtained by the method of the present invention. Are shown together with their target values and MFR values that are conventional indicators of fluidity.

  The calculation of the apparent activation energy Ea in Tables 1 and 2 is preferably performed using “RPA2000 manufactured by Alpha Technologies, Inc.” as a viscoelasticity measuring device, and is evaluated based on the temperature range and shear rate used during extrusion. Measurement and calculation were performed under the following conditions.

Measurement conditions Temperature: 180 ° C-200 ° C-220 ° C
Shear rate: 6.98 1 / s
(Distortion 14%, frequency 50 rad / s)
Calculation method: Arrhenius type (Andrade's formula)
η = Aexp (Ea / RT) (1)
However,
η: Viscosity Ea: Apparent activation energy (of flow) T: Temperature R: Gas constant

  The complex viscosity η * (η) of 180 ° C.-200 ° C.-220 ° C. is calculated from the above measurement conditions, and these are plotted in the above equation (1) to calculate Ea.

  Further, the rate of change G * r, which is the shear rate dependence of the complex elastic modulus G *, is desirably evaluated at the temperature used during extrusion, using “RPA2000 manufactured by Alpha Technologies, Inc.” as a viscoelasticity measuring device. Therefore, measurement and calculation were performed under the following conditions.

Measurement conditions Temperature: 200 ° C
Shear rate: (a) 10.0 1 / s
(Frequency 100 rad / s, distortion 10.04%)
(B) 19.8 1 / s
(Frequency 100 rad / s, distortion rate 19.95%)
The complex elastic modulus G * r at the shear rate (a) and (b) was plotted in the following equation (2) to calculate the rate of change G * r.

G * r (%) = {G *} of (b) / {G * r} of (a) × 100 (2)
Further, M in Tables 1 and 2 is defined as a radial rate (%) on the Ea-G * r characteristic, and was calculated as follows. That is, as shown in FIG. 6, if an extrusion molded product extruded with the material A is a B part, the target width of each value of Ea and G * r is Ea ₁ to Ea ₂ and G * r. _{When determined as 1 to} G * r ₂ , the middle point of the target width region determined by the values of Ea and G * r is set to M ₀ . When the distance from the intermediate point M ₀ to the origin is D ₀ , the radial rate M of an arbitrary point M ₁ (Ea _M1 , G * r _M1 ) is calculated by the following equation (3).

M = D ₁ / D ₀ × 100 (%) (3)
However,
D ₁ = {(G * r _M1 ) ² + (Ea _M1 ) ² } ^1/2
D ₀ = [{(Ea ₂ + Ea ₁ ) / 2} ² +
(G * r ₂ + G * r ₁ ) / 2} ² ] ^1/2
Tables 1 and 2 show the viscoelastic properties and fluidity (MFR value) as well as the mechanical properties, tensile set rate, and extrudability (extrusion processability) evaluation results.

  The MFR value, which is an index of fluidity in Tables 1 and 2, is a value at 230 ° C. × 2.16 kg load (g / 10 min) in accordance with JIS K7120.

  Among the mechanical properties, the hardness (durometer A hardness) is based on JIS K6253, and the tensile strength (MPa) and maximum elongation (%) are values based on JIS K6251.

  As for the tensile permanent set, a permanent set (%) at 20% elongation was measured using a JIS No. 3 dumbbell (sheet having a thickness of 2 mm) at 70 ° C. × 100 H.

  In addition, the average extrusion discharge amount of the extrudability evaluation items in Tables 1 and 2 is an average of 1 minute when extruded after adjusting the screw rotation speed to 70 rpm and the discharge temperature to 200 ° C. with a φ65 single screw extruder. The discharge amount (number of samples n = 50) is obtained.

  Similarly, the discharge amount variation rate (%) of the extrudability evaluation items in Tables 1 and 2 is the following formula (4): variation in the discharge weight per minute (number of samples n = 50) under the above-described extrusion conditions. It is what I have requested.

Discharge rate variation rate (%) = {(maximum discharge amount (g) −minimum discharge amount (g)) / average discharge amount (g)} × 100 (4)
The cross-sectional shape evaluation of the extrudability evaluation items in Tables 1 and 2 was performed as follows. First, when the screw rotation speed is 70 rpm in sample a (extruder having a diameter of 65), a die having an extrusion port shape that matches the shape shown in FIG. 7 is prepared. And arbitrary samples (compound-shaped thing) were put from the feed part, and the sample was collected from 15 minutes after the extrudate was extruded.

  In that case, the sample number n is set to n = 50, a sample for evaluating the discharge amount variation rate is collected every minute, and a sample for evaluating the extruded cross-sectional shape is collected from the 50 samples (the tenth, 25th and 50th). As a cross-sectional shape evaluation method, after the extrusion, it was quenched and hardened and cut, and the cross-sectional shape was measured. The shape determination is OK when all three cross sections are within the dimensional tolerances a to h (± 0.2 mm) in FIG. 7 (Note that the dimensions of each side in FIG. 7 are a = 6 mm, b = 2 mm, for example) , C = 11 mm, d = 11 mm, e = 3 mm, f = 7 mm, g = 7 mm, h = 4 mm).

  In addition, the adjustment screw rotation speed of the extrudability evaluation item in Tables 1 and 2 indicates whether or not there is a screw rotation speed at which the cross-sectional shape can be extruded within the dimensional tolerance. If not, “Adjustment difficulty” is displayed.

  Similarly, the evaluation of the surface appearance of the extrusion-molded product in the extrudability evaluation items in Tables 1 and 2 is a visual observation of the surface appearance of the extrusion-molded product extruded for the previous cross-sectional shape evaluation.

  The evaluation items of mechanical properties and extrusion moldability related to the apparent activation energy Ea in Tables 1 and 2 are hardness, tensile strength, maximum elongation as well as average extrusion discharge amount and discharge amount variation as described above. Rate and surface appearance evaluation of the extruded product.

  In addition, the evaluation items of mechanical properties and extrusion moldability related to the complex elastic modulus change rate G * r in Tables 1 and 2 are the hardness, tensile strength, maximum elongation, average extrusion discharge amount, adjusting screw as well. It is rotation speed and cross-sectional shape evaluation.

  Furthermore, the evaluation items of the extrusion moldability related to the radial rate M in Tables 1 and 2 are the average extrusion discharge amount, the adjusting screw rotation speed, and the cross-sectional shape evaluation.

  As apparent from Tables 1 and 2, samples a to which the apparent activation energy Ea, the change rate G * r of the complex elastic modulus, and the radial rate M all satisfy the target values obtained by the method of the present invention. In the case of e, the overall evaluation is all “◯ (good)”, while on the other hand, the samples f to j in which at least one of the Ea value, the G * r value, and the M value is outside the target value are all “ X (defect) ”.

  From this, it is possible to determine that the material is excellent in quality and excellent in extrudability if at least the values of Ea and G * r are both within the control range. This means that the compound morphology can be evaluated by the values of both Ea and G * r, and as a result, the mechanical properties and extrusion property of the material can be evaluated and managed.

  For example, in sample g, although the MFR value, which is the conventional determination method, is within the target range, the value of Ea is not within the target range, so there is a possibility that the appearance appearance of the extruded product deteriorates. It can be determined to be high. Further, even if the MFR value is within the target range as in sample i, since the value of G * r does not satisfy the target value, it can be determined that the mechanical properties of the material are deteriorated and the quality is deteriorated.

  In addition, it is possible to determine whether or not the cross-sectional shape can be accurately extruded with M derived from the correlation between the Ea value and the G * r value. Since the M value has a correlation with the screw rotation speed, the screw rotation speed is evaluated. It can also be used as an indicator. This can be easily understood from the fact that there is a close correlation as shown in FIG. 8 when plotting the adjusting screw rotation speed and the value of the radial rate M in Tables 1 and 2.

  As described above, the evaluation based on the apparent activation energy Ea and the change rate G * r of the complex elastic modulus of the present invention can obtain accurate information on the mechanical properties and extrusion processability (extrusion moldability) of the extruded product. Even if it is not extruded in the actual product shape, the characteristic evaluation can be performed with high accuracy in a short time by obtaining the Ea value and the G * r value. In particular, when the radial rate M having a correlation with the Ea value and the G * r value is used in combination, the effect becomes more remarkable.

  FIG. 1 shows an example of a more specific viscoelasticity testing apparatus for carrying out the method of the present invention. In FIG. 1, reference numeral 1 denotes a viscoelasticity measuring machine. The viscoelasticity measuring machine 1 controls a temperature chamber and a sample chamber in which a sample of a thermoplastic elastomer to be measured is accommodated, a vibration frequency and a vibration amplitude of the sample. A drive mechanism that applies a shearing force and a converter that detects reaction torque and converts it into an electrical signal are provided.

  Reference numeral 2 denotes an A / D converter that converts an analog signal corresponding to the reaction torque output from the viscoelasticity measuring device 1 into a digital signal. Reference numeral 3 denotes an information processing apparatus that stores a signal from the A / D converter 2 and performs processing by reading the stored data after the measurement is completed.

  4 of the information processing device 3 is an Ea arithmetic device, which calculates a complex viscosity η * (η) based on data (data corresponding to the reaction torque) stored in the output of the A / D converter 2. It has a function of calculating the apparent activation energy Ea from η * (η) based on the above-described equation (1).

  Reference numeral 5 denotes a storage device that stores in advance a range of Ea values that can be molded for each material (for example, target value ranges shown in Tables 1 and 2) as a setting range. 6 compares the setting range of the Ea value calculated by the Ea calculation device 4 and the Ea value stored in the storage device 5, and whether or not the mechanical properties of the material such as the discharge amount variability and the appearance appearance and the extrudability are appropriate An arithmetic device that performs the determination.

  Reference numeral 7 denotes a storage device that stores the calculation result of the calculation device 6 together with the calculation result of the Ea calculation device 4. 8 is G * for calculating the rate of change G * r of the complex elastic modulus G * from the data (data corresponding to the reaction torque) stored in the output of the A / D converter 2 based on the above-described equation (2). r arithmetic unit. Reference numeral 9 denotes a storage device that stores the calculation result of the G * r calculation device 8.

  A discharge amount control device 10 controls the extrusion discharge amount of the extruder based on the data stored in the storage devices 7 and 9. The discharge amount control device 10 is configured as shown in FIG. 2, for example.

  In FIG. 2, reference numeral 11 denotes a storage device that stores in advance, as setting ranges, the extrusion conditions for each material and the G * r range (for example, target value ranges as shown in Tables 1 and 2) for each extruded product. is there. Reference numeral 12 denotes an arithmetic device that performs a comparison determination between a G * r range (setting range) that can be molded based on information for each extrusion-molded product and the calculated value of G * r stored in the storage device 9. In the storage device 5 relating to the Ea value described above, the range (setting range) of the moldable Ea value for each material is stored, whereas in the storage device 11, the extrusion conditions for each material are stored. At the same time, a set range of G * r values that can be molded with respect to the material for each extruded product is stored in advance.

  Reference numeral 13 denotes an arithmetic unit that calculates the radial rate M based on the previous equation (3) based on the calculated values of Ea and G * r stored in the respective storage devices 7 and 9. Reference numeral 14 denotes an arithmetic unit that calculates an extrusion discharge amount based on the above-described radial rate M based on information for each extrusion-molded product. Reference numeral 15 denotes an arithmetic unit that sets various conditions in extrusion molding for each extrusion molding product according to the material to be used. Reference numeral 16 denotes an extrusion condition control device that determines the extrusion screw rotation speed, the extrusion temperature, and the die type that meet the conditions set by the arithmetic unit 15 and controls the extruder 20.

  Here, the flowchart for determining the value of the apparent activation energy Ea described above is, for example, as shown in FIG. This flowchart is executed as a program of the CPU of the viscoelasticity testing apparatus shown in FIGS.

In FIG. 3, first, as a preparation stage, a specific sample (here, for example, sample A) is set in a testing machine (viscoelasticity measuring machine 1 in FIG. 1) (step S ₁ ), and sample A and the viscoelasticity measuring machine are set. After preheating 1 (step S ₂ ), the test is started (step S ₃ ).

After starting the test, the tester control (steps S ₄ and S ₅ ) described on the right side of the flowchart and the data storage (steps S ₆ and S ₇ ) described on the left side are performed in parallel.

In step S ₄ , the viscoelasticity measuring device 1 of FIG. 1 inputs a shear force at an arbitrary temperature, vibration frequency, and vibration amplitude to the sample A, and detects the reaction output torque. This is performed until predetermined data collection is completed (step S ₅ ). In step S ₆ , the test collection data is A / D converted and stored in the storage device. This is performed until predetermined data collection is completed (step S ₇ ).

When the data collection is completed, in step S _8, reads the stored data, calculates the * complex viscosity eta (eta) from the output torque. Then, to calculate the activation energy Ea apparent performs operation based on equation (1) previously described in the next step S _9.

On the other hand, it calls the range (setting range) of the extrusion molded article formable Ea value previously stored for each (part be molded object) of each material in step S _10, in step S _11, Ea for Sample A Are compared with the settable range of the moldable Ea value for the sample A, and the extrusion processability evaluation for the sample A is performed.

As a result, if the calculated value of Ea is within the preliminarily stored moldable Ea value setting range, the extrudability of the sample A based on the Ea value is determined to be OK (Step S ₁₂ ). If the calculated value of Ea is out of the moldable setting range, the extrudability of the sample A based on the Ea value is determined to be NG (step S ₁₃ ). In this case, as described above based on the data in Tables 1 and 2, the Ea value of a specific thermoplastic elastomer and the mechanical properties of an extruded product made from the thermoplastic elastomer, that is, hardness and tensile strength, and There is a close correlation between the highest elongation, since it is possible to simultaneously predict, step S ₁₁ to S ₁₃ in the appropriateness determining simultaneously the mechanical properties and evaluation of extrusion processability of the sample a is performed at the same time become.

  On the other hand, a flowchart for determining the value of the rate of change G * r of the complex elastic modulus G * is, for example, as shown in FIG. This flowchart is executed as a CPU program of the viscoelasticity testing apparatus shown in FIGS.

In FIG. 4, first, as a preparation stage, sample A is set in a testing machine (viscoelasticity measuring machine 1 in FIG. 1) (step S ₁ ), sample A and the testing machine are preheated (step S ₂ ), and the test is started. (step S _3).

After starting the test, the tester control (steps S ₄ and S ₅ ) described on the right side of the flowchart and the data storage (steps S ₆ and S ₇ ) described on the left side are performed in parallel.

In step S ₄ , the viscoelasticity measuring device 1 of FIG. 1 inputs a shear force at an arbitrary temperature, vibration frequency, and vibration amplitude to the sample A, and detects the reaction output torque. This is performed until predetermined data collection is completed (step S ₅ ). In the step S ₆ is stored in the storage device test data A / D converter to. This is performed until predetermined data collection is completed (step S ₇ ).

When the data collection is completed, in step S _8, reads the stored data, calculates the complex modulus G * from the output torque. Then, at the next step S _9, it calculates the complex modulus G * change rate G * r on the basis of the equation (2) described above.

On the other hand, in step S _10, a set range of G * r values that can be molded and stored in advance for each molding condition (cross-sectional shape) of the extruded product (part to be molded) of each material is called, and step S ₁₁ , The calculated value of G * r for the sample A and the set range of the G * r value for a specific extrusion-molded product using the sample A as a raw material, for example, an extrusion-molded product (part) T, are collated. The evaluation judgment is performed.

As a result, if the calculated value of G * r is within the pre-stored G * r value setting range, the extrudability of sample A and extruded product (part) T by the G * r value is If it is determined to be OK (step S ₁₂ ) and the value is outside the preset range of the G * r value stored in advance, the extrudability of the sample A and the extruded product (part) T by the G * r value is It is determined as NG (step S ₁₃ ). In this case, as described above based on the data in Tables 1 and 2, the G * r value of a specific thermoplastic elastomer and the mechanical properties of an extruded product made from the thermoplastic elastomer, that is, hardness and tensile Since there is a close correlation between strength and maximum elongation and simultaneous prediction is possible, in steps S _{11 to} S ₁₃ , the mechanical properties of the sample A and the extruded product T are evaluated simultaneously with the evaluation of the extrusion processability. Suitability determination is performed at the same time.

  FIG. 5 shows a production management flowchart to which the present invention is applied.

First, in step S ₁ , the materials are kneaded under the set kneading conditions to obtain a kneaded material (here, sample A) (step S ₂ ). Then, for example, viscoelasticity measurement similar to that of FIGS. 3 and 4 is performed by the viscoelasticity measuring device 1 of FIG. 1 and data necessary for calculation of the Ea value and G * r value is collected (step S ₃ ). Then, calculates the activation energy Ea apparent based on the foregoing equation (1) in step S _4.

In step S _5, and compares the setting range of Ea value of the sample A which has been previously stored calculation value of Ea calculated in step S _4, performs the propriety determination of extrudability for the sample A. As a result, if the calculated value of Ea is within the preset Ea value setting range, it is determined that the extrusion processability of the sample A is OK (step S ₆ ), and in the next step S ₇ . The process proceeds to the calculation of the change rate G * r of the complex elastic modulus G *.

Next, the calculated value of G * r is collated with the set range of the G * r value of a specific extrusion molded product (here, referred to as part B) made of sample A stored in advance, performing suitability judgment extrusion of the component B to the sample a as a material (step S _8). That is, if the calculated value of G * r is within a preset G * r value setting range, it is determined that the extrudability of the part B made of the sample A is OK (step S). ₉ ).

Then, in step S ₁₀ that follows, to calculate the dynamic diameter ratio M on the basis of the equation (3) described above on the basis of the calculated value of Ea and G * r. Furthermore, M value stored in advance in advance samples A, component B in step S ₂₀ - with reference to the correlation data of the screw rotational speed, the optimum extrusion to extruded components B to the sample A and the material The screw rotation speed (extrusion discharge amount) of the machine is calculated (step S ₁₁ ). Then, the calculated screw rotation speed is input to the extruder (step S ₁₂ ), and extrusion molding is started (step S ₁₃ ). The above-mentioned correlation data of M value-screw rotation number is shown in FIG.

If it is determined in the previous step S ₈ that the calculated value of G * r for the part B made of the sample A is outside the preset G * r value setting range, extrusion processability of component B to the sample a and the material from that no other than to the determination unsuitable, in step S _14, G * r value other extrudate to the sample a as a material (parts) Compare with the setting range. As a result, if the calculated value of G * r for the sample A is within the set range of the G * r value of other parts made from the sample A, the sample A should be used for extruding other parts. The determination result is recorded (step S ₁₅ ).

Note that, in step S _5, it is determined that or if the calculated value of Ea for Sample A is determined to be outside the range, but the calculated value of G * r is outside the range in the step S ₁₄ In such a case, the property of the sample A itself is determined to be inappropriate, and an instruction to change the kneading conditions is issued.

  As described above, the thermoplastic elastomer is used as a raw material by using the apparent activation energy Ea, the change rate G * r of the complex elastic modulus G *, and the value of the radial modulus M, which enables accurate evaluation of the extrusion processability. It is possible to perform production management when extruding the extruded product.

Also, as shown in step S ₂₀ , by creating correlation data between the radial velocity ratio M and the screw rotation number in advance, it is possible to save the trouble of calculating the screw rotation number each time and start actual extrusion molding. The required setup time is greatly reduced.

  In addition, the viscoelasticity measuring device 1 of FIG. 1 can collect | require the data of the complex viscosity and complex elastic modulus in room temperature-230 degreeC, for example.

The block diagram for calculating apparent activation energy Ea and change rate G * r of complex elastic modulus G * by a viscoelasticity test. The block diagram which shows the principal part structure of FIG. The flowchart which shows an example of the process at the time of evaluating extrusion processability by the apparent activation energy Ea. The flowchart which shows an example of the process at the time of evaluating extrusion processability by change rate G * r of complex elastic modulus G *. The flowchart which shows an example of the process at the time of evaluating extrusion processability by apparent activation energy Ea, the rate of change G * r of the complex elastic modulus G *, and the radial rate M, and managing production. Explanatory drawing of the radial rate M defined by the correlation with apparent activation energy Ea and change rate G * r of complex elastic modulus G *. Explanatory drawing which shows the cross-sectional shape for extrusion cross-sectional shape evaluation as one of extrusion processability evaluation. The graph which shows the correlation with radial velocity M and screw rotation speed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Viscoelasticity measuring machine 2 ... A / D converter 3 ... Information processing apparatus 4 ... Ea arithmetic unit 5, 7, 9, 11 ... Storage device 6, 12, 13, 14, 15 ... Arithmetic unit 8 ... G * r Arithmetic unit 10 ... Discharge amount control unit 16 ... Extrusion condition control unit 20 ... Extruder

Claims (14)

The thermoplastic elastomer is controlled on the basis of the stress acting against the shearing force by controlling the shearing force applied to the thermoplastic elastomer produced under the predetermined kneading conditions by changing the vibration frequency and vibration amplitude within the predetermined temperature range. Measuring the complex viscosity η * (η) of the two, and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates;
The temperature and gas constants at the time of the above measurement are T and R, the viscosity is η, the complex viscosity is η * (η), the apparent activation energy is Ea, and the Arrhenius type equation representing the temperature dependence of the viscoelastic material. Calculating the apparent activation energy Ea of the thermoplastic elastomer based on (Andrade formula) (1);
η = Aexp (Ea / RT) (1)
However,
Ea: Abbreviation for Activation Energy, apparent activation energy of compound viscosity (flow) (× 10 ⁻¹ KJ / mol)
Calculating a rate of change G * r (abbreviation of G * rate) of the complex modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex modulus G * obtained previously; ,
Including
It is characterized in that the mechanical properties and extrusion processability of an extruded product made of a thermoplastic elastomer are evaluated based on the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G *. For evaluating the properties of thermoplastic elastomers.   For each of a plurality of thermoplastic elastomers having the same composition and different kneading conditions, the allowable range of the apparent activation energy Ea that can be molded in the extrusion process and the allowable range of the change rate G * r of the complex elastic modulus G * are set. 2. The method for evaluating characteristics of a thermoplastic elastomer according to claim 1, wherein the method is set in advance.   The method for evaluating the properties of a thermoplastic elastomer according to claim 1 or 2, wherein the mechanical properties are at least the hardness, tensile strength, and maximum elongation of an extruded product made of a thermoplastic elastomer.   The above extrusion processability is an extruder that can make at least the average extrusion discharge amount of the thermoplastic elastomer at the time of extrusion molding, the discharge amount variation rate, the appearance appearance of the extrusion molding product, and the cross-sectional shape of the extrusion molding product within the tolerance. The method for evaluating the properties of a thermoplastic elastomer according to any one of claims 1 to 3, wherein the screw rotational speed and the cross-sectional shape of the extruded product are good or bad. The thermoplastic elastomer is controlled on the basis of the stress acting against the shearing force by controlling the shearing force applied to the thermoplastic elastomer produced under the predetermined kneading conditions by changing the vibration frequency and vibration amplitude within the predetermined temperature range. Measuring means for determining the complex viscosity η * (η) and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates;
Equation (1) representing the temperature dependence of the viscoelastic material, where T and R are the temperature and gas constant at the time of the measurement, the viscosity is η, the complex viscosity is η * (η), and the apparent activation energy is Ea. A first calculating means for calculating an apparent activation energy Ea of the thermoplastic elastomer based on
A second computing means for calculating a rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously;
For each of a plurality of thermoplastic elastomers having the same composition and different kneading conditions, the allowable ranges of the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * that can be molded in the extrusion molding process are set in advance. Set storage means,
The apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated by the first and second calculating means, and the activation energy Ea and the complex elastic modulus stored in the storage means A determination means for evaluating the mechanical properties and molding processability of an extruded product made of a thermoplastic elastomer by individually comparing each allowable range of the change rate G * r of G *,
An apparatus for evaluating the characteristics of a thermoplastic elastomer, comprising: The thermoplastic elastomer is controlled on the basis of the stress acting against the shearing force by controlling the shearing force applied to the thermoplastic elastomer produced under the predetermined kneading conditions by changing the vibration frequency and vibration amplitude within the predetermined temperature range. Measuring the complex viscosity η * (η) of the two, and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates;
Equation (1) representing the temperature dependence of the viscoelastic material, where T and R are the temperature and gas constant at the time of the measurement, the viscosity is η, the complex viscosity is η * (η), and the apparent activation energy is Ea. Calculating the apparent activation energy Ea of the thermoplastic elastomer based on
A step of calculating a rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously;
On the correlation data in which the correlation between the allowable width of the apparent activation energy Ea and the allowable width of the change rate G * r of the complex elastic modulus G * is predetermined, the apparent activation energy Ea and the complex elasticity previously determined The step of calculating the relative positional relationship between the intermediate point of the allowable width on the correlation data and the measured point position as the radial rate M when the measured point position is designated with the change rate G * r value of the rate G *. When,
Including
A heat characterized by setting the extrusion conditions of the thermoplastic elastomer based on the values of the apparent activation energy Ea calculated above, the change rate G * r of the complex elastic modulus G *, and the radial modulus M. Processing conditions setting method for plastic elastomer. Prior to setting the extrusion conditions for thermoplastic elastomer,
Each of the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated previously, and the preset activation energy Ea and the change rate G * r of the complex elastic modulus G *, respectively. The processing of a thermoplastic elastomer according to claim 6, further comprising a determination step for evaluating the extrusion processability of an extruded product made of a thermoplastic elastomer as a raw material by individually comparing with an allowable range. Condition setting method.   Apparent activation energy Ea and complex elasticity that can be molded in the extrusion process for each of the cases where extrusion molding is performed under specific extrusion conditions using a plurality of thermoplastic elastomers having the same composition and different kneading conditions The method for setting processing conditions for a thermoplastic elastomer according to claim 7, wherein each allowable range of the rate of change G * r of the rate G * is set in advance. A correlation between the allowable width of the apparent activation energy Ea and the allowable width of the change rate G * r of the complex elastic modulus G * is determined in advance on the condition that the evaluation result of the extrudability in the determination step is good. In the correlation data, when the measured point position is designated with the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated previously, the allowable width on the correlation data is Calculating a relative positional relationship between the intermediate point and the measured point position as a radial rate M;
A discharge amount calculating step for calculating an extrusion discharge amount of a thermoplastic elastomer suitable for extruding a specific extruded product based on the radial rate M,
A step of setting the extrusion processing conditions of the extrusion-molded product based on the extrusion discharge amount previously calculated in the discharge amount calculation step for the extrusion-molded product determined to have good extrudability by the determination means; ,
The method for setting processing conditions for a thermoplastic elastomer according to claim 7 or 8, wherein   In the step of setting the extrusion process condition, the correlation data between the preset radial velocity M and the screw rotation speed of the extruder is compared with the previously calculated radial velocity M, and the calculated radial radius is checked. The method for setting processing conditions for a thermoplastic elastomer according to claim 9, wherein a screw rotation number corresponding to the rate M is calculated. The thermoplastic elastomer is controlled on the basis of the stress acting against the shearing force by controlling the shearing force applied to the thermoplastic elastomer produced under the predetermined kneading conditions by changing the vibration frequency and vibration amplitude within the predetermined temperature range. Measuring means for determining the complex viscosity η * (η) and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates;
Equation (1) representing the temperature dependence of the viscoelastic material, where T and R are the temperature and gas constant at the time of the measurement, the viscosity is η, the complex viscosity is η * (η), and the apparent activation energy is Ea. A first calculating means for calculating an apparent activation energy Ea of the thermoplastic elastomer based on
A second computing means for calculating a rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously;
On the correlation data in which the correlation between the allowable width of the apparent activation energy Ea and the allowable width of the change rate G * r of the complex elastic modulus G * is determined in advance, the apparent activation energy Ea and the complex elasticity previously calculated When the actual measurement point position is designated with the change rate G * r value of the rate G *, the relative positional relationship between the intermediate point of the allowable width on the correlation data and the actual measurement point position is calculated as the radial rate M. 3 computing means;
Apparent activation energy Ea and complex elasticity that can be molded in the extrusion process for each of the cases where extrusion molding is performed under specific extrusion conditions using a plurality of thermoplastic elastomers having the same composition and different kneading conditions Storage means in which each allowable range of the rate of change G * r of the rate G * is preset;
The apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated by the first and second calculating means, and the activation energy Ea and the complex elastic modulus G stored in the storage means A judging means for evaluating the extrudability of an extruded product made of a thermoplastic elastomer by individually comparing each allowable range of the change rate G * r of *, and
A discharge amount calculating means for calculating an extrusion discharge amount of a thermoplastic elastomer suitable for extruding a specific extrusion-molded product based on the radial ratio M calculated by the third calculation means;
Condition setting means for setting the extrusion processing conditions of the extruded product based on the extrusion discharge amount calculated by the discharge amount calculation means for the extrusion molded product determined to have good extrudability by the determination means;
A device for controlling an extrusion discharge amount of a thermoplastic elastomer, comprising: The discharge amount calculation means collates correlation data between a preset radial rate M and the screw rotation speed of the extruder with the previously calculated radial rate M, and calculates the calculated radial rate M. While calculating the screw rotation speed suitable for
12. The extrusion discharge amount control of a thermoplastic elastomer according to claim 11, wherein the condition setting means gives the extruder the screw rotational speed previously calculated prior to the start of extrusion molding by the extruder. apparatus. The thermoplastic elastomer is controlled on the basis of the stress acting against the shearing force by controlling the shearing force applied to the thermoplastic elastomer produced under the predetermined kneading conditions by changing the vibration frequency and vibration amplitude within the predetermined temperature range. Measuring the complex viscosity η * (η) of the two, and the complex elastic modulus G * of the thermoplastic elastomer in two shear regions having different shear rates;
Equation (1) representing the temperature dependence of the viscoelastic material, where T and R are the temperature and gas constant at the time of the measurement, the viscosity is η, the complex viscosity is η * (η), and the apparent activation energy is Ea. Calculating the apparent activation energy Ea of the thermoplastic elastomer based on
A step of calculating a rate of change G * r of the complex elastic modulus G * representing the shear rate dependence of the viscoelastic property based on the ratio of the two complex elastic modulus G * obtained previously;
Each of the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * calculated previously, and the preset activation energy Ea and the change rate G * r of the complex elastic modulus G *, respectively. A judgment process for evaluating the extrudability of an extruded product made of a thermoplastic elastomer as a raw material by individually comparing the allowable range;
A correlation between the allowable width of the apparent activation energy Ea and the allowable width of the change rate G * r of the complex elastic modulus G * is determined in advance on the condition that the evaluation result of the extrudability in the determination step is good. When the actual measurement point position is designated with the apparent activation energy Ea and the change rate G * r of the complex elastic modulus G * obtained previously on the correlation data, the allowable width on the correlation data is determined. Calculating a relative positional relationship between the intermediate point and the measured point position as a radial rate M;
A discharge amount calculating step for calculating an extrusion discharge amount of a thermoplastic elastomer suitable for extruding a specific extruded product based on the radial rate M,
Including
The extruder is controlled so as to be the extrusion discharge amount calculated in the discharge amount calculation step, and the kneading condition of the thermoplastic elastomer is changed when it is determined that the molding process is impossible in the determination step. The processing management method of thermoplastic elastomer.   In the discharge amount calculating step, correlation data between a preset radial rate M and the screw rotation speed of the extruder is compared with the previously calculated radial rate M, and the calculated radial rate M is checked. 14. The process management method for a thermoplastic elastomer according to claim 13, wherein a screw rotation number commensurate with is calculated.

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