JP2016087975A - Flow analyzer with resin viscosity calculation function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow analyzer with a resin viscosity calculation function for a development support device for performing simulation analysis of a behavior when a resin accompanying a plurality of curing reactions is injected to a mold to be molded, which has such a resin viscosity calculation function as to accurately calculate a change of the viscosity of the resin, and accordingly accurately grasp resin flow behavior in the mold and can find out an appropriate molding condition, a mold cavity shape, the number of injection ports, the arrangement and the like, on the side of the flow analysis.SOLUTION: A flow analyzer is configured to: measure a heat quantity of a resin, and measure a synthetic heat generation curve of a first heat generation curve exhibiting a curing reaction by polymerization and a second heat generation curve exhibiting a curing reaction by crystallization (S10); separate (calculate) the synthetic heat generation curve into the first and second heat generation curves, and calculate a degree α of cure of the resin, based on the first heat generation curve (S12); multiply initial viscosity of the resin by a value related to the calculated degree α of cure to calculate a viscosity ηp by polymerization of the resin (S16); and input the viscosity ηp to a development support device (S18).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a flow analysis apparatus having a resin viscosity calculation function, and more specifically, a computer-aided development support apparatus (Computer Aided Engineering) that analyzes a behavior of a resin injected into a mold cavity through a computer simulation. The present invention relates to a flow analysis apparatus having a resin viscosity calculation function.

  As a device that supports the development of mold design, product design, etc. through computer simulation, the resin flow behavior in the mold during molding using the finite element method, finite volume method, difference method, boundary element method, etc. Simulation technology is already widely used for resin parts.

  In order to perform the simulation, it is necessary to input resin physical properties to a computer in advance. Necessary resin physical properties include viscosity, thermal conductivity, specific heat, density, and the like. Viscosity is an important physical property that significantly affects the flow behavior.

  By the way, in the molding, there is a process in which a monomer is shaped with a chemical reaction (crosslinking, polymerization, etc.) while pouring into a mold controlled at a high temperature or after pouring. For example, molding using a thermosetting resin such as an epoxy resin involves a curing reaction by crosslinking. In order to obtain a reliable analysis result, the resin flow behavior in the mold must be simulated after a viscosity curve fitting equation that accurately matches the viscosity changing with time while producing a reaction is input to the computer.

  In the simulation using a resin with a curing reaction, the viscosity changes in a complicated manner. Therefore, as described in Patent Documents 1 and 2 below, the flow behavior of a fluid resin is analyzed using a finite element method or the like. It is known to do.

JP 2003-068776 A JP 2014-058049 A

  The technologies described in Patent Documents 1 and 2 are widely used only for thermosetting resins that cause one kind of curing reaction such as epoxy resins, but some resins cause two kinds of curing reactions. To do. For example, in the synthesis of nylon 6 using ε-caprolactam as a raw material monomer, two types of curing reactions, polymerization as the first curing reaction (short time side) and crystallization as the second curing reaction (long time side), are performed. Arise. Therefore, the techniques described in Patent Documents 1 and 2 cannot cope with such a resin having a plurality of curing reactions.

  Therefore, the object of the present invention is to solve the above-mentioned problems, and to analyze the behavior when a resin with a plurality of curing reactions is injected into a mold cavity and molded through a computer simulation, the resin viscosity for a development support apparatus In a flow analysis device with a calculation function, the viscosity change of the resin is accurately calculated, so the flow analysis side accurately understands the flow behavior of the resin in the mold cavity, and appropriate molding conditions, mold cavity shape, injection An object of the present invention is to provide a flow analysis apparatus having a resin viscosity calculation function that makes it possible to find out the number and arrangement thereof.

  In order to solve the above-described problems, in claim 1, the development is performed to analyze the behavior when a resin containing a resin raw material component that causes a plurality of reactions is injected into a mold cavity and molded through a computer simulation. In the flow analysis apparatus having a resin viscosity calculation function for a support apparatus, a first exotherm indicating a curing reaction due to polymerization in m seconds after the start of temperature rise by measuring the differential scanning calorific value of the resin to be injected into the mold cavity. A synthetic exothermic curve measuring means for measuring a synthetic exothermic curve composed of a curve and a second exothermic curve showing a curing reaction by crystallization after n (n> m) seconds, and the measured synthetic exothermic curve is First and second heat generation curve separating means for separating (calculating) the first heat generation curve and the second heat generation curve, and the degree of cure α of the resin based on the separated first heat generation curve. A degree-of-curing calculation means, a viscosity calculating means for calculating the viscosity ηp due to the polymerization of the resin by multiplying the initial viscosity of the resin by a value related to the calculated degree of curing α, and the polymerization of the calculated resin And an input means for inputting the viscosity ηp by the development support apparatus.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 2, the first and second exothermic curve separation means measure the differential scanning calorific value of the resin and o (o> n ) Measuring an endothermic curve due to crystal melting after 2 seconds, separating (calculating) the second exothermic curve based on the measured endothermic curve, and subtracting the separated second exothermic curve from the synthetic exothermic curve. Thus, the first heat generation curve is separated.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 3, the first and second exothermic curve separating means raise the temperature to the synthetic exothermic curve in the measurement of the differential scanning calorific value of the resin. Later, after cooling, the temperature was raised again and the endothermic curve was measured.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 4, the viscosity calculation means calculates a crystallinity degree Xc of the resin based on the separated second heat generation curve, and the degree of cure. The viscosity ηp due to polymerization of the resin calculated from α is multiplied by the value related to the calculated crystallinity Xc to calculate the viscosity ηpc due to polymerization and crystallization of the resin, and the input means The viscosity ηpc resulting from polymerization and crystallization of the resin was configured to be input to the development support device.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 5, the viscosity change measuring means for measuring the viscosity change curve of the resin, and the equation (1) based on the measured viscosity change curve Viscosity correction means for correcting so as to improve the fitting accuracy of viscosity ηp due to polymerization of the calculated resin by changing a plurality of parameters, and the input means, the viscosity ηp due to polymerization of the corrected resin is It was configured to input to the development support device.

  In the flow analysis apparatus having the resin viscosity calculation function according to claim 6, the viscosity change measuring means for measuring the viscosity change curve of the resin, and the equation (1a) based on the measured viscosity change curve Viscosity correction means for correcting so as to further improve the fitting accuracy of viscosity ηpc due to polymerization and crystallization of the calculated resin by changing a plurality of parameters, and the input means includes the polymerization of the corrected resin The viscosity ηpc resulting from crystallization was input to the development support apparatus.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 7, the first and second heat generation curve separating means synthesize the separated first heat generation curve and second heat generation curve again. A verification means for verifying whether or not it matches the synthetic heat generation curve is provided.

  In the flow analysis apparatus having the resin viscosity calculation function according to claim 1, the differential scanning calorific value of the resin to be injected into the mold cavity is measured to indicate a curing reaction by polymerization after m seconds from the start of temperature increase. A synthetic exothermic curve synthesized with the first exothermic curve and a second exothermic curve showing a curing reaction by crystallization after n (n> m) seconds is measured, and the measured synthetic exothermic curve is defined as a first exothermic curve. The resin is separated into the second heat generation curve, the degree of cure α of the resin is calculated based on the separated first heat generation curve, and the initial viscosity of the resin is multiplied by the value related to the calculated degree of cure α, resulting from the polymerization of the resin. Since the viscosity ηp is calculated and the calculated viscosity ηp due to the polymerization of the resin is input to the development support device, it is possible to appropriately calculate the change in viscosity of the resin that causes multiple curing reactions. In mold cavity It is possible to accurately grasp the flow behavior of the resin and find appropriate molding conditions, mold cavity shape, number of injection ports and their arrangement, and the like.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 2, the differential scanning calorific value of the resin is measured to measure an endothermic curve due to crystal melting after o (o> n) seconds from the start of temperature rise, The second heat generation curve is separated based on the measured endothermic curve, and the first heat generation curve is separated by subtracting the second heat generation curve separated from the combined heat generation curve. The first and second heat generation curves can be easily separated (or calculated).

  In the flow analysis apparatus having the resin viscosity calculation function according to claim 3, the first and second exothermic curve separating means temporarily raise the temperature to the synthetic exothermic curve in the measurement of the differential scanning calorific value of the resin. After cooling, the temperature is increased again to measure the endothermic curve. In addition to the above effects, the exothermic curve due to polymerization and crystallization and the endothermic curve due to crystal melting should be measured separately. It is also possible to increase the degree of freedom of testing.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 4, the degree of crystallinity Xc of the resin is calculated based on the separated second heat generation curve, and the polymerization of the resin calculated from the degree of cure α is performed. By multiplying the viscosity ηp by the value related to the calculated crystallinity Xc, the viscosity ηpc due to polymerization and crystallization of the resin is calculated, and the calculated ηpc due to polymerization and crystallization of the resin is input to the development support device. Since it is configured, it is possible to more appropriately calculate the viscosity change of the resin that causes multiple curing reactions, and the flow analysis side accurately grasps the flow behavior of the resin in the mold cavity, and more appropriate molding conditions, The mold cavity shape, the number of injection ports and their arrangement can be found.

  In the flow analysis apparatus having the resin viscosity calculation function according to claim 5, the viscosity change curve of the resin is measured, and the calculation is performed by changing a plurality of parameters of the formula (1) based on the measured viscosity change curve. In addition to the effects described above, the viscosity change due to the polymerized resin is corrected so that the fitting accuracy of the viscosity ηp due to the polymerization of the resin is improved and the viscosity ηp due to the polymerization of the corrected resin is input to the development support device. It can be calculated more appropriately.

  In the flow analysis apparatus having a resin viscosity calculation function according to claim 6, the viscosity change curve of the resin is measured, and the calculation is performed by changing a plurality of parameters of formula (1a) based on the measured viscosity change curve. The ηpc fitting accuracy due to polymerization and crystallization of the corrected resin is corrected to be further improved, and the corrected ηpc due to polymerization and crystallization of the resin is input to the development support apparatus. In addition, the change in viscosity can be calculated more appropriately.

  The flow analysis apparatus having a resin viscosity calculation function according to claim 7 is configured to verify whether or not the separated first heat generation curve and second heat generation curve are combined again to match the combined heat generation curve. In addition, when the degree of coincidence is insufficient, the separation can be corrected. Therefore, in addition to the above effects, the viscosity change can be calculated more appropriately.

It is explanatory drawing which shows the process from the product design performed using the flow analysis apparatus which has a viscosity calculation function which concerns on 1st Example of this invention to mass production. It is a flowchart which shows the process of the apparatus shown in FIG. It is a data figure which shows the measurement result of the whole calorie | heat amount curve obtained by the process of FIG. FIG. 3 is a data diagram showing calculation results of a first heat generation curve and a second heat generation curve separated from a combined heat generation curve obtained by the process of FIG. 2. It is a data figure which shows the measurement result of the synthetic | combination exothermic curve and endothermic curve obtained by the process of FIG. FIG. 3 is a data diagram showing a result of verifying whether or not the first heat generation curve and the second heat generation curve separated from the combined heat generation curve obtained by the process of FIG. It is a data figure which shows the measurement result and calculation result of the viscosity obtained by the process of FIG. It is a flowchart which shows the process of the flow analysis apparatus which has a viscosity calculation function based on 2nd Example of this invention. It is a data figure which shows the measurement result and calculation result of the viscosity obtained by the process of FIG.

  Hereinafter, an embodiment for carrying out a flow analyzing apparatus having a viscosity calculating function according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is an explanatory view showing steps from product design to mass production performed using a flow analysis apparatus having a viscosity calculation function according to the first embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes a flow analysis device having a viscosity calculation function, and the device 10 is configured as a device for a development support device (CAE) 12, more specifically as a device constituting a part of the development support device 12. The The development support apparatus 12 includes a computer, and stores an interactive simulation program 16 for analyzing the resin flow behavior in the mold 14.

  The mold 14 includes an upper mold 14a and a lower mold 14b, and a cavity 14c is formed therebetween. The resin 14 is injected (filled) into the cavity 14c from an injection path formed in the upper mold 14a by an injection machine 14d. The resin 20 is made of a monomer obtained by mixing a plurality of reactive raw resin components. The cavity 14c is connected to a decompression pump 14e so as to be decompressed (evacuated).

  The development support device (computer) 12 includes a display 12a and an input means 12b such as a keyboard and a mouse, and is molded by injecting the resin 20 into the mold cavity 14c, more specifically, molding such as RTM (Resin Transfer Molding) method. The behavior at the time of performing is analyzed through simulation by the stored interactive program 16.

  The flow analysis apparatus 10 having the viscosity calculation function shares the development support apparatus 12 and the simulation program 16, and the DSC analyzer 22 for measuring the DSC (Differential Scanning Calorimetry) of the resin 20, The measurement result from the rheometer 24 for measuring the viscosity is sent. The development support apparatus 12 may use two or more computers and send the results of calculating the viscosity change by a computer for resin viscosity calculation function to another computer for flow analysis for analysis. Further, the DSC analyzer 22 and the rheometer 24 specifically measure the heat quantity and viscosity of the sample of the resin 20 to be injected into the mold cavity 14c.

  Specifically, the flow analysis is performed as part of the process from product design to mass production, and the designer (engineer) inputs data via the input device 12b and follows the instructions stored in the program 16 in an interactive format. A product model 26 is designed.

  In CAE, when a product is manufactured using the mold 14, the designer first designs the product model 26 in the product design process, and uses the created product model 26 to mold the mold model 28 in the mold design process. To design.

  Next, the designer creates mold machining data using the created mold model 28, uses the data to produce the mold 14 using the NC machining apparatus 30, and uses the produced mold 14. Then, the product 32 is manufactured by performing molding such as the RTM method.

  FIG. 2 is a flow chart showing processing of the flow analysis apparatus 10 having a viscosity calculation function, and FIGS. 3 to 7 are explanatory diagrams showing measurement results such as heat generation curves obtained thereby. 2 is executed by the development support apparatus (computer) 12.

  In the following description, DSC (differential scanning calorie) is measured using the DSC analyzer 22 while heating the resin 20 at a constant heating rate condition, for example, 4 ° C./min in S10, and two kinds of curing reactions occur. An exothermic curve a and an endothermic curve d when crystal melting occurs are measured. Specifically, the resin 20 is composed of a mixture of ε-caprolactam, a catalyst, a polymerization initiator and the like that are solid granular at room temperature as a raw material monomer for nylon 6.

  FIG. 3 shows the measurement results. As shown in the figure, the endotherm due to the melting and liquefaction of the monomer at around 70 ° C. is caused by heat generation due to polymerization (first heat generation curve b) and heat generation due to crystallization (second heat generation curve c) at around 120 to 170 ° C. However, an endotherm (endothermic curve d) due to melting and liquefaction of polymer crystals was observed at around 200 to 220 ° C.

  It should be noted that in this calorimetric curve measurement, even in the caloric curve measurement in which the temperature of the resin is raised to the heat generated by crystallization (second exothermic curve c), and then once cooled, the temperature is raised again at around 200 to 220 ° C. The endotherm (endothermic curve d) was observed.

  In FIG. 3, since the horizontal axis indicates the temperature when heated at a constant rate of temperature increase, the exothermic curve a is the first that occurs on the short time side that precedes in time (in other words, m seconds after the start of temperature increase). And the exothermic curve b of the second curing reaction (crystallization) that occurs on the long time side (in other words, n (n> m) seconds after the start of temperature increase). Composed of a synthetic heat generation curve.

  Molding must be performed within a range of molding conditions (the size of the molded product, the temperature of the resin 20, and the temperature of the mold 14) that allow the resin 20 to reach the end in the mold cavity 14c. That is, since it is necessary to complete the flow (injection) within a range in which sufficient fluidity is ensured in the resin 20, the viscosity curve fitting for the simulation does not increase the viscosity sufficiently. In this case, the accuracy on the low viscosity (short time) side where the curing reaction has not sufficiently progressed becomes important. The first embodiment was made paying attention to this point.

  Therefore, the combined heat generation curve a measured in S12 is separated into the first heat generation curve b and the second heat generation curve c, and the curing degree α (t) is calculated from the first heat generation curve b and the like. FIG. 4 shows the separated first heat generation curve b and second heat generation curve c.

  The separation will be described. As described above, the low temperature side of the synthetic exothermic curve a undergoes a curing reaction due to polymerization, and the high temperature side undergoes a curing reaction due to crystallization. Separated (calculated) from the exothermic curve c.

  That is, the amount of heat generated by crystallization as the second curing reaction (the amount of heat generated by the second heat generation curve c) is recognized on the higher temperature side (in other words, o (o> n) seconds after the start of temperature increase). It is theoretically equal to the endothermic amount due to melting of the formed crystal (endothermic amount of the endothermic curve d). Accordingly, when the area of the combined heat generation curve a is S, the area of the first heat generation curve b is S1, the area of the second heat generation curve c is S2, and the area of the heat absorption curve d is S3, the second heat generation curve a is shown in FIG. The area S2 of the exothermic curve c is equal to the area S3 of the endothermic curve d.

  In calculating the area S3 of the endothermic curve d, in the measurement of the calorific value curve, the temperature of the resin is raised to the heat generated by crystallization (second exothermic curve c), then cooled once, and the temperature is raised again. You may employ | adopt the endotherm (endothermic curve d) seen by a measurement.

  The first and second heat generation curves b and c are separated using distribution curves (Gaussian distribution, Cauchy distribution, etc.) used in statistics. In the case of the example, the Gaussian distribution shown in Equation 1 was used (μ: average value, σ: standard deviation). That is, the second heat generation curve c is calculated by using a Gaussian distribution curve having different half widths on the left and right so that the area S2 is equal to S3, and the calculated second heat generation curve c is subtracted from the combined heat generation curve a. A first exothermic curve b was calculated. Since these curve shapes are often not symmetrical, distribution curves having different half widths on the left and right may be used.

  Thus, in S12, the measured combined heat generation curve a is separated into the first heat generation curve b and the second heat generation curve c.

  More specifically, the DSC analyzer 22 is used to measure the differential scanning calorific value of the resin 20, and the first exothermic curve b and n (n>) due to polymerization, which is the first curing reaction that occurs m seconds after the start of temperature increase. m) A synthetic exothermic curve a consisting of a second exothermic curve c due to crystallization, which is a second curing reaction occurring after 2 seconds, and an endothermic curve d due to crystal melting occurring after o (o> n) seconds are measured. Next, the combined heat generation curve a is separated into a first heat generation curve b and a second heat generation curve c. First, the area S2 (heat generation amount) of the second heat generation curve c is equal to the area S3 (heat absorption amount) of the endothermic curve d, and the high temperature side of the combined heat generation curve a and the second heat generation curve c as shown in FIG. A distribution curve (Equation 1-1) is set so that the high temperature side substantially matches, and the second heat generation curve c is calculated. Further, the first heat generation curve b is calculated by subtracting the calculated second heat generation curve c from the combined heat generation curve a. By this procedure, the first heat generation curve b and the second heat generation curve c are separated.

  In the process of S12, the curing degree α (t) is then calculated from the calculated first heat generation curve b and the like.

  Formula 2-1 (predetermined formula (1)) in Formula 2 shows a viscosity curve fitting formula for obtaining the viscosity ηp (t) using the degree of cure α (t) or the like. The initial viscosity ηtp (T, γ dot) of Formula 2-1 is obtained from Formula 2-2, and the curing reaction rate dα / dt is expressed by Formula 2-3.

  In Equation 2, ηp: viscosity due to polymerization of resin, ηtp: initial viscosity, t: time, T: temperature, γ dot: shear rate, αgel: degree of cure at the gel point, α: degree of cure, E1, E2, E3, F1, C1, C2, C3, A1, A2, m, and n are reaction viscosity parameters of the resin.

  In this way, the degree of cure α (t) based only on polymerization is calculated from the first exothermic curve b and Equation 2-3. By applying Formula 2-3 to these data, the optimum values of each parameter such as A1, A2, E1, E2, m, and n can be obtained.

  In the process of S12, after separating the combined heat generation curve a into the first and second heat generation curves b and c, the separated first heat generation curve b and second heat generation curve c are again represented as shown in FIG. A combined exothermic curve a ′ is generated by synthesis, and it is verified whether or not it matches the measured synthetic exothermic curve a (shown in FIG. 3).

  In the flow chart of FIG. 2, the process then proceeds to S14, where the rheometer 24 is used to measure the change over time in the viscosity data of the resin 20 under the conditions of isothermal heating and constant shear rate. FIG. 7 shows the change over time of the measured viscosity data.

  Next, in S16, the degree of cure α (t) calculated from the separated first heat generation curve b using Equation 2-3 in Equation 2 is substituted into Equation 2-1 (predetermined Equation (1)), and the resin The viscosity ηp (t) due to polymerization of 20 is calculated. Formula 2-1 generally calculates the viscosity ηp (t) due to polymerization of the resin 20 cured by polymerization by multiplying the initial viscosity ηtp (T, γ dots) by a value related to the calculated degree of cure α. Configured to do.

  At this time, A 1, A 2, C 1, and E 2 of Formula 2 (Formulas 2-1 to 2-2, 2-3) so that the viscosity curve calculated by Formula 2-1 matches the actual measurement data shown in FIG. Viscosity curve fitting (curve fitting) is performed by determining parameters such as C2, C3, E1, E2, E3, F1, m, and n.

  FIG. 7 shows the results of viscosity curve fitting according to the example. In the figure, the solid line is the measured value, and the broken line is the fitting value calculated from the first heat generation curve b. For reference, fitting values calculated from the first exothermic curve b and the second exothermic curve c (shown later in the second embodiment) are also shown by a one-dot chain line. In the case shown in FIG. 7, since the temperature of the resin 20 is as low as 110 ° C. and only the first curing reaction has occurred, it has been confirmed that the fitting value agrees well with the measured value over time.

  Next, in S18, the calculated viscosity ηp (t) due to the polymerization of the resin is input to the development support device 12, and the resin flow behavior in the mold cavity 14c is analyzed through a computer simulation.

  Since this embodiment is configured as described above, the viscosity change of the resin 20 that causes a plurality of curing reactions can be calculated appropriately, and the flow behavior of the resin in the mold cavity 14c can be accurately grasped on the flow analysis side. Therefore, it is possible to find appropriate molding conditions, mold cavity shape, number of injection ports and their arrangement, and the like.

  FIG. 8 is a flow chart similar to FIG. 2 showing the processing of the flow analyzing apparatus 10 having the viscosity calculating function according to the second embodiment of the present invention.

  In addition, since the structure of the flow analysis apparatus 10 which has the viscosity calculation function which concerns on 2nd Example is not different from 1st Example shown in FIG. 1, description is abbreviate | omitted.

  In the first example, the viscosity curve was fitted so that the low viscosity (short time) side of the condition where the viscosity slowly increased at a relatively low temperature (the curing reaction did not proceed sufficiently) matched. Even under conditions where the viscosity increases rapidly at a high temperature (the curing reaction proceeds sufficiently), it is necessary to predict when the low viscosity can be secured, so not only the low viscosity (short time) side but also the high It is desirable that the viscosity curve can be fitted on the viscosity (long time) side.

  Therefore, in the second embodiment, the viscosity curve is obtained by using the first exothermic curve b due to polymerization, which is a curing reaction occurring on the short time side, and the second exothermic curve c due to crystallization, which is the curing reaction occurring on the long time side. Fitting was performed.

  Referring to the flowchart of FIG. 8, the processing from S100 to S106 is performed in the same manner as the processing from S10 to S16 in the flowchart of FIG. A degree of conversion Xc (t) is calculated.

  That is, when the second exothermic curve c is crystallized, the formula 2 cannot be used as it is, so the crystallinity Xc (t) is used as an alternative to the curing degree α (t). The crystallinity Xc (t) was calculated from the generalized Abram formula 3-1 shown in Equation 3 (ρc: crystal part density, ρl: amorphous part density, G: nucleus growth rate, N: nucleation frequency. V: crystal volume).

  The spherulite size r necessary for calculating the crystal volume V is expressed by the formula 3-3, and the nucleus growth rate G and the nucleation frequency N are expressed by the formulas 3-4 to 3-6 (Tm: melting point, Tg: glass transition). Point, C1, C2: WLF constant, C3, C4, Gc, Nc: resin parameter).

  As described above, in the second embodiment, the second exothermic curve c and the equation are calculated as in the first embodiment, the degree of cure α (t) by only the polymerization is calculated from the first exothermic curve b and the equation 2-3. The crystallinity degree Xc (t) by crystallization was calculated from 3-1. By applying the equation shown in Equation 3 to these data, the optimum values of each parameter such as the nucleus growth rate G, nucleation frequency N, spherulite size r, crystal volume V, resin parameters C3, C4, Gc, and Nc can be obtained. . Known values are used for the crystal part density ρc, the amorphous part density ρl, the melting point Tm, the glass transition point Tg, and the WLF constants C1 and C2.

  In addition, a new viscosity curve fitting formula has been devised. That is, since the second curing reaction occurs during or after the change of the viscosity due to the first curing reaction, the second curing reaction is added to the viscosity obtained by the viscosity change formula 2-1 by the first curing reaction. Devised a formula. Equation 4 shows the equation.

  In Equation 4, ηpc: viscosity due to resin polymerization and crystallization, ηp: viscosity due to resin polymerization, Xcmax: maximum crystallinity, Xc: crystallinity, t: time, E4, F2 are reaction viscosity parameters of the resin .

  In S108, the degree of cure α (t) calculated using the separated first heat generation curve b and Equation 2-3, and the second heat generation curve c and Equation 3-1, which are calculated, are used. The viscosity ηpc (t) due to polymerization and crystallization of the resin 20 is calculated from the obtained crystallinity Xc (t) using Equation 4-1 (predetermined equation (1a)) of Equation 4. In general, Equation 4-1 can be obtained by multiplying the viscosity ηp (t) of the resin 20 cured by polymerization by a value related to the calculated crystallinity Xc, thereby polymerizing and crystallizing the resin 20 cured by crystallization. It is comprised so that the viscosity (eta) pc (t) by may be calculated.

  FIG. 9 shows the result of viscosity curve fitting according to the second embodiment. In FIG. 9, as in FIG. 7, the solid line represents the measured value, the broken line represents the fitting value ηp (t) calculated from the first heat generation curve b, and the alternate long and short dash line represents the first heat generation curve b and the second heat generation curve c. The fitted value ηpc (t) is shown.

  Compared to the first embodiment, in the case of the second embodiment, since the temperature is raised to a relatively high temperature of 140 ° C., the crystallization, which is the second curing reaction, is also progressing. Although the fitting value ηp (t) due to the reaction alone deviates from the measured value over time, it should be confirmed that the fitting value ηpc (t) due to the first curing reaction and the second curing reaction is in good agreement with the measured value. I was able to.

  Next, in S110, the calculated viscosity ηpc (t) due to polymerization and crystallization of the resin is input to the development support apparatus 12, and the resin flow behavior in the mold cavity 14c is analyzed through a computer simulation.

  Since the second embodiment is configured as described above, the viscosity change of the resin 20 that causes two or more types of curing reactions can be calculated more appropriately, and the flow behavior of the resin in the mold cavity 14c can be calculated on the flow analysis side. By grasping with high accuracy, it is possible to find appropriate molding conditions, mold cavity shape, number of injection ports and their arrangement, and the like.

  As described above, in the first and second embodiments of the present invention, a computer simulation of the behavior when the resin 20 containing a resin raw material component that causes a plurality of reactions is injected into the mold cavity 14c and molded. In the flow analysis apparatus 10 having a resin viscosity calculation function for the development support apparatus 12 to be analyzed through, the differential scanning calorific value of the resin 20 to be injected into the mold cavity 14c is measured, and m seconds after the start of temperature increase. Synthetic exothermic curve measurement for measuring a synthetic exothermic curve a synthesized from a first exothermic curve b showing a curing reaction by polymerization and a second exothermic curve c showing a curing reaction by crystallization after n (n> m) seconds. Means (DSC analyzers 22, S10, S100) and first and second heat generation curves for separating the measured combined heat generation curve a into the first heat generation curve b and the second heat generation curve c. Separation means (S12, S102), a degree of cure calculation means (S12, S102) for calculating the degree of cure α (t) of the resin 20 based on the separated first heat generation curve b, The initial viscosity ηtp (t) is multiplied by a value related to the calculated degree of cure α, and more specifically, the viscosity ηp (t) due to polymerization of the resin 20 is calculated based on a predetermined formula (1). Since it is configured to include a viscosity calculating means (S16, S106) and an input means (S18, S110) for inputting the calculated viscosity ηp (t) due to polymerization of the resin to the development support apparatus 12, a plurality of curings are provided. The viscosity change of the resin causing the reaction can be calculated appropriately, the flow analysis side accurately grasps the flow behavior of the resin in the mold cavity, and appropriate molding conditions, mold cavity shape, number of injection ports and their arrangement Etc. Can be found.

  The first and second exothermic curve separating means (S12, S102) measure the differential scanning calorific value of the resin 20 to obtain an endothermic curve d due to crystal melting after o (o> n) seconds from the start of temperature rise. Measuring and separating the second heat generation curve c based on the measured heat absorption curve d, and subtracting the separated second heat generation curve c from the combined heat generation curve a to obtain the first heat generation curve b. Since it is configured to be separated, the first and second heat generation curves b and c can be easily separated (or calculated) in addition to the effects described above.

  Further, the first and second exothermic curve separating means (S12, S102), in the measurement of the differential scanning calorific value of the resin 20, after raising the temperature to the synthetic exothermic curve a, once cooling it and then increasing again. In addition to the effects described above, it is possible to separately measure the exothermic curve due to polymerization and crystallization and the endothermic curve due to crystal melting in addition to the above effect. Can increase the degree of freedom.

  The viscosity calculating means (S16, S106) calculates the crystallinity Xc (t) of the resin 20 based on the separated second heat generation curve c, and is calculated from the degree of curing α (t). Multiplication of the resin 20 by the viscosity ηp (t) by a value related to the calculated crystallinity Xc, more specifically, the polymerization and crystallization of the resin 20 based on a predetermined formula (1a). And the input means (S18, S110) are configured to input the calculated viscosity ηpc (t) due to polymerization and crystallization of the resin to the development support device 12. It is possible to calculate more appropriately the viscosity change of the resin that causes multiple curing reactions, and accurately understand the flow behavior of the resin in the mold cavity on the flow analysis side, more appropriate molding conditions, mold cavity shape The number of inlets and It can be found the arrangement or the like.

  Further, a viscosity change measuring means (rheometer 24, S14, S104) for measuring a viscosity change curve of the resin 20, and a plurality of parameters of the equation (1) are changed based on the measured viscosity change curve, Viscosity correcting means (S16, S106) for correcting the calculated viscosity ηp (t) due to polymerization of the resin to improve the fitting accuracy is provided, and the input means (S18, S110) is the corrected polymerization of the resin. Since the viscosity ηp (t) is input to the development support apparatus 12, in addition to the effects described above, the viscosity change can be calculated more appropriately.

  Further, the viscosity change measuring means (rheometer 24, S104) for measuring the viscosity change curve of the resin 20 and the plurality of parameters of the equation (1a) are changed based on the measured viscosity change curve. And a viscosity correction means (S108) for correcting the viscosity ηpc (t) resulting from the polymerization and crystallization of the resin to further improve the fitting accuracy, and the input means (S110) includes the polymerization and crystallization of the corrected resin. Since the configuration is such that the viscosity ηpc (t) resulting from the conversion is input to the development support device 12, in addition to the effects described above, the viscosity change can be calculated more appropriately.

  Further, the first and second heat generation curve separating means (S12, S102) again synthesize the separated first heat generation curve b and the second heat generation curve c to determine whether or not they match the combined heat generation curve a. In addition to the effects described above, the viscosity change can be calculated more appropriately because the verification means (S12, S102) is provided.

  In the above examples, synthesis of nylon 6 by polymerization of ε-caprolactam and crystallization thereof were taken as examples, and exothermic curves were separated by two curing reactions of polymerization and crystallization. When measurement is possible independently, a synthetic exothermic curve resulting from three or more exothermic reactions can be separated using the same separation (calculation) method.

  The same applies to the case where the combined endothermic curve is separated using an independent heat generation curve. It goes without saying that the raw materials and chemical reactions that occur are not limited to these. The apparatus configuration is not limited to the disclosed one.

  10 Flow Analysis Device with Viscosity Calculation Function, 12 Development Support Device (Computer), 12a Display, 12b Input Means, 14 Mold, 14a Upper Mold, 14b Lower Mold, 14c Cavity, 14d Injection Machine, 20 Resin, 22 DSC Analysis 24 rheometer

Claims (7)

  In the flow analysis apparatus having a resin viscosity calculation function for a development support apparatus that analyzes a behavior when injecting a resin containing a resin raw material component in which a plurality of reactions occur into a mold cavity through a computer simulation, A first exothermic curve showing a curing reaction by polymerization after m seconds from the start of temperature rise by measuring the differential scanning calorie of the resin to be injected into the mold cavity, and curing by crystallization after n (n> m) seconds A synthetic exothermic curve measuring means for measuring a synthetic exothermic curve synthesized with a second exothermic curve indicating a reaction; and a first for separating the measured synthetic exothermic curve into the first exothermic curve and the second exothermic curve. A second exothermic curve separating means; a curing degree calculating means for calculating the degree of curing α of the resin based on the separated first exothermic curve; and the calculated initial viscosity of the resin. Viscosity calculating means for calculating the viscosity ηp due to polymerization of the resin by multiplying a value related to the degree of cure α, and input means for inputting the calculated viscosity ηp due to polymerization of the resin to the development support device A flow analysis apparatus having a resin viscosity calculation function.   The first and second exothermic curve separating means measure a differential scanning calorie of the resin, measure an endothermic curve due to crystal melting after o (o> n) seconds from the start of temperature rise, and measure the endothermic curve. The resin viscosity according to claim 1, wherein the second heat generation curve is separated based on the first heat generation curve, and the first heat generation curve is separated by subtracting the separated second heat generation curve from the combined heat generation curve. Flow analysis device with calculation function.   The first and second exothermic curve separating means, in measuring the differential scanning calorific value of the resin, after raising the temperature to the combined exothermic curve, once cooling, then raising the temperature again and measuring to the endothermic curve The flow analysis apparatus having a resin viscosity calculation function according to claim 2.   The viscosity calculating means calculates a crystallinity degree Xc of the resin based on the separated second exothermic curve, and calculates the crystallinity degree calculated from the resin polymerization viscosity ηp calculated from the curing degree α. The viscosity ηpc due to polymerization and crystallization of the resin is calculated by multiplying the value related to Xc, and the input means inputs the calculated viscosity ηpc due to polymerization and crystallization of the resin to the development support device. A flow analysis apparatus having a resin viscosity calculation function according to claim 2 or 3.   Viscosity change measuring means for measuring the viscosity change curve of the resin, and correcting the calculated viscosity ηp due to polymerization of the resin by changing a plurality of parameters of the formula (1) based on the measured viscosity change curve 4. The resin viscosity calculation function according to claim 1, further comprising: a viscosity correction unit configured to input the viscosity ηp due to polymerization of the corrected resin to the development support device. A flow analysis apparatus.   Viscosity change measuring means for measuring the viscosity change curve of the resin, and changing the plurality of parameters of the formula (1a) based on the measured viscosity change curve, the calculated viscosity due to polymerization and crystallization of the resin 5. The resin viscosity calculating function according to claim 4, further comprising a viscosity correcting means for correcting ηpc, wherein the input means inputs the corrected viscosity ηpc due to polymerization and crystallization of the resin to the development support apparatus. A flow analysis apparatus. The first and second heat generation curve separating means includes verification means for recombining the separated first heat generation curve and the second heat generation curve to verify whether or not they match the combined heat generation curve. A flow analysis apparatus having a resin viscosity calculation function according to any one of claims 1 to 6.

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