JP4248482B2 - Sample measuring device - Google Patents

Description

The present invention relates to a sample measuring device for measuring material properties, and more particularly to a composite sample measuring device for measuring various physical properties such as material viscosity, PVT characteristics, and thermal conductivity.

In recent years, development of high-quality materials has become an urgent issue, and attention has been focused on how to perform material property evaluation of a sample (sample) in a small amount in a short time. Usually, viscosity measurement is roughly classified into a capillary type viscosity measuring device and a rotary viscometer. In order to measure the melt viscosity, it is necessary to change the temperature and the deformation (strain) speed. In particular, in a capillary type viscosity measuring apparatus, it is extruded in one direction, and a large amount of sample is required for each measurement condition. On the other hand, a rotational viscometer can measure a relatively small amount of sample, but has a limit in deformation speed (up to about 1000 s ⁻¹ ). In addition, since the melt viscosity measuring device and the PVT measuring device are independent stand-alone formats, it takes a long time measurement and a lot of labor to obtain the material property data necessary for understanding the molding process. .

(1) It is an object of the present invention to provide a sample measuring apparatus capable of performing a plurality of measurements in a short time using the same sample.
(2) Alternatively, the present invention is to provide a sample measuring apparatus capable of measuring with a small amount of sample.
(3) Alternatively, the present invention is to provide a composite sample measuring apparatus capable of performing a plurality of types of measurements in a short time using the same sample.
(4) Alternatively, an object of the present invention is to provide a scalable composite type sample measuring apparatus capable of performing a plurality of types of measurements.

The present invention includes a measurement channel through which a sample moves, a first cylinder chamber and a second cylinder chamber that are arranged at both ends of the measurement channel and communicate with the measurement channel, and a first piston that moves in the first cylinder chamber. A second piston that moves in the second cylinder chamber, at least two pressure sensors that are arranged along the measurement channel and measure the pressure in the measurement channel, and a third cylinder that communicates with the first cylinder chamber A chamber, and a third piston and a fourth piston that move in the third cylinder chamber , the sample in the measurement channel is pressed by the first piston and the second piston and moved along the measurement channel, and at least The pressure of the sample in the measurement channel is measured by two pressure sensors , the communication between the first cylinder chamber and the third cylinder chamber is interrupted by the third piston or the fourth piston, and the third piston and the fourth piston are used. 3rd cylinder chamber Pressing the sample, in the sample measuring apparatus.

(1) Sample measuring device The sample measuring device mainly measures characteristics of an organic material such as plastic, and includes a measurement channel, a first cylinder chamber and a second cylinder chamber communicating with the measurement channel, A first piston that moves in the one cylinder chamber, a second piston that moves in the second cylinder chamber, and a plurality of pressure sensors that measure the pressure in the measurement flow path are provided. For example, as shown in FIGS. 1 to 2, the sample measuring apparatus includes a measurement channel 11 in which a sample moves, a first cylinder chamber (for example, an upper cylinder chamber) 23 that communicates with the measurement channel 11, and a first channel. Two cylinder chambers (for example, a lower cylinder chamber) 33, a first piston (for example, an upper piston) 21 that moves in the upper cylinder chamber 23, and a second piston (for example, a lower piston) that moves in the lower cylinder chamber 33 31 and a plurality of pressure sensors 5, 5, 5 for measuring the pressure in the measurement flow path 11. The upper piston 21 and the lower piston 31 are moved in the upper cylinder chamber 23 and the lower cylinder chamber 33, the sample in the measurement channel 11 is flowed upward or downward, and the sample is moved along the measurement channel 11. . At that time, the pressure of the sample in the measurement channel is measured by the pressure sensors 5, 5, 5. Since the sample can be repeatedly moved upward or downward, a plurality of measurements can be performed in a short time using the same sample. In the sample measuring device, the measurement flow path 11 is slit-shaped (thin strip-shaped) to reduce the internal volume, so that even a small amount of sample can be measured.

In addition, the sample measuring apparatus includes a third cylinder chamber (lateral cylinder chamber) 43 in a direction intersecting the lower cylinder chamber 33 and a third piston (for example, a left cylinder) disposed to face the lateral cylinder chamber 43. Chamber) 41 and a fourth piston (for example, a right cylinder chamber) 42 may be provided. Thereby, the sample used in the measurement of the measurement channel 11 is guided to the lateral cylinder chamber 43 and pressed by the left piston 41 and the right piston 42 to measure the characteristics of the sample under the pressurization condition and temperature condition. Can do. By adopting such a structure, the same sample can be used to measure multiple types of characteristics in a short time and with a simple operation, and a scalable composite type sample measuring device should be obtained. Can do.

(2) Measurement flow path The measurement flow path 11 is preferably one that allows a small amount of sample to pass as smoothly as possible. For this purpose, the measurement flow path 11 has a slit shape such as a thin strip-shaped space, a strip-shaped space, a thin rectangular parallelepiped space, or a thin and long plate-shaped space. That is, the slit shape is a space specified by the slit gap 111, the slit width 112, and the slit flow path length 113, and the slit gap 111 is extremely smaller than the slit width 112 and the slit flow path length 113. It is short, and the slit channel length 113 forms the channel direction. The slit gap 111 and the slit width 112 form the shape of the cross section (opening) of the measurement flow path 11 to be an elongated rectangle. The wide surface of the measurement channel 11 is a surface formed by the slit width 112 and the slit channel length 113. The slit shape is a shape in which the number of samples existing in the space is reduced as much as possible. For example, the number of samples in the slit shape is less than half, or even less than one third, compared to a measurement channel having a circular cross section. Is. In other words, the measurement channel 11 has a thin and long plate shape, the thickness (slit gap 111) is much shorter than the plate width (slit width 112), and the plate length (slit channel length). 113) forms a space longer than the plate width (slit width 112). In forming the measurement channel 11, for example, as shown in FIG. 3, a pair of blocks are bonded to each other, and the measurement channel 11 (strip-shaped gap) is provided between them to produce a measurement channel block (slit die) 1. To do. The measurement channel 11 penetrates the measurement channel block 1 to form the measurement channel 11. The slit shape of the measurement channel 11 is, for example, a slit gap 111 (plate thickness) 0.4 mm, a slit width 112 (plate width) 9 mm, and a slit channel length 113 (plate length) 50 mm. Conventionally, a sample of about 20 cc was required for one measurement, but the measurement can be performed with a small amount of sample of 8 to 10 cc by the slit-shaped measurement channel.

(3) Pressure Sensor The pressure sensor 5 is a device that measures the pressure of the sample in the measurement channel 11, and measures at least two locations along the measurement channel 11. In FIG. 2, three pressure sensors 5, 5, 5 are arranged at three locations along the vertical direction of the measurement channel block 1. The pressure measurement unit of each pressure sensor 5 is embedded in the measurement channel block 1 and faces the wide surface of the measurement channel 11 having a wide slit (the surface formed by the slit width 112 and the slit channel length 113). The pressure of the sample at each location of the measurement flow path 11 can be measured. Thereby, since the pressure sensor 5 contacts the sample of a wide area, it can measure a pressure correctly.

(4) Temperature control device and temperature measurement device The temperature control device and the temperature measurement device are not shown in the figure, but the temperature control device is partially provided on the measurement channel block 1, the upper cylinder 22, the lower cylinder 32, the flange 34, and the like. Install a temperature measuring device. The temperature control device controls the temperature of the sample, and the temperature measurement device measures the temperature of the sample. When the temperature control device is attached to the measurement channel block 1, for example, a heater and a control device that controls the current flowing to the heater are used. The heater covers all one block, and current is supplied to the heater to perform temperature control. The temperature measurement device uses a thermocouple thermometer, for example, and inserts it into a small hole formed in the measurement channel block 1 to measure the temperature.

(5) Upper cylinder chamber and lower cylinder chamber, upper piston and lower piston The upper cylinder chamber 23 and the lower cylinder chamber 33 are disposed in communication with the upper and lower portions of the measurement flow path 11. The upper cylinder chamber 23 communicates with the measurement flow path 11 by attaching the upper cylinder 22 to the upper end of the measurement flow path block 1 as shown in FIGS. The lower cylinder chamber 33 communicates with the measurement flow path 11 by attaching the lower cylinder 32 to the lower end of the measurement flow path block 1. The measurement channel block 1 is disposed between the upper cylinder 22 and the lower cylinder 32, and the flange 24 protrudes in the outer peripheral direction of the lower portion of the upper cylinder 22 and the flange 34 protrudes in the outer peripheral direction of the upper portion of the lower cylinder 32. Is fixed with bolts 12, 12, 12, 12, the upper cylinder chamber 23, the measurement flow path 11 and the lower cylinder chamber 33 can be fixed integrally. When the upper cylinder chamber 23 or the lower cylinder chamber 33 is circular, the diameter is, for example, 3.6 mm.

  The upper piston 21 moves in a liquid-tight manner on the inner wall surface of the upper cylinder chamber 23 so that the sample does not leak. The lower piston 31 moves in a liquid-tight manner on the inner wall surface of the lower cylinder chamber 33 so that the sample does not leak. It is preferable that the upper piston 21 and the lower piston 31 can move to a position that is substantially in contact with the end of the measurement channel 11 of the measurement channel block 1.

When the upper piston 21 and the lower piston 31 move upward in each cylinder chamber, the sample moves upward in the measurement channel 11. When the upper piston 21 and the lower piston 31 move downward in each cylinder chamber, the sample moves downward in the measurement channel 11. By moving the upper piston 21 and the lower piston 31 upward or downward in synchronization, the sample can be smoothly moved upward or downward many times. Since the piston can be moved at a high speed or a low speed, the deformation speed of the sample can be arbitrarily specified, and dynamic measurement is possible.

(6) Lateral cylinder chamber, left piston and right piston The lateral cylinder chamber 43 is disposed so as to intersect the upper cylinder chamber 23 or the lower cylinder chamber 33. The lateral cylinder chamber 43 may be integrally formed in the upper cylinder 22 or the lower cylinder 32, or may be formed separately as a lateral cylinder. In FIG. 1 to FIG. 2, the lateral cylinder chamber 43 is formed integrally with the upper portion in the lower cylinder 32 and communicates with the lower cylinder chamber 33. The horizontal cylinder chamber 43 and the lower cylinder chamber 33 are arranged orthogonally. The diameter of the horizontal cylinder chamber 43 is, for example, 3.6 mm.

  The left piston 41 and the right piston 42 are disposed opposite to each other in the horizontal cylinder chamber 43, and slide the inner wall surface of the horizontal cylinder chamber 42 in a liquid-tight manner so that the sample does not leak through the horizontal cylinder chamber 43. Move to move. At least one of the left piston 41 and the right piston 42 crosses the intersecting lower cylinder chamber 33 and can further move in the lateral cylinder chamber 43. Further, at least one of the left piston 41 and the right piston 42 crosses the lower cylinder chamber 43 and can block communication between the lower cylinder chamber 33 and the lateral cylinder chamber 43.

  The left piston 41 and the right piston 42 can press the sample in the lateral cylinder chamber 43 and can apply arbitrary pressure to the sample. Although not shown, a temperature control device that controls the temperature of the sample in the horizontal cylinder chamber 43 and a temperature measurement device that measures the temperature are arranged, and a volume measurement device that measures the volume of the sample in the horizontal cylinder chamber And a pressure measuring device for measuring the pressure. As the volume measuring device, for example, a position measuring device that measures the relative position of the left piston 41 and the right piston 42 or a displacement measuring device that measures the displacement of the third piston or the fourth piston can be used. As the pressure measuring device, for example, a load cell attached to the left piston 41 or the right piston 42 can be used. With these measuring devices, the PVT (pressure, specific volume, temperature) behavior of the sample can be measured, and a composite sample measuring device can be obtained. Further, the thermal conductivity of the sample can be measured using a temperature control device or a temperature measurement device. As described above, the sample measuring apparatus can perform various measurements by providing chambers and ports in the measurement flow path block 1, the upper cylinder 22, the lower cylinder 32, and the like, and has expandability. In addition, the sample measuring apparatus can move the sample to any position because the measurement channel 11, the upper cylinder chamber 23, the lower cylinder chamber 33, the lateral cylinder chamber 43, and the like communicate with each other. It is possible to minimize the waste of the sample.

Although the horizontal cylinder chamber 43 is not shown in the drawing, a plurality of the horizontal cylinder chambers 43 may be provided as necessary and arranged so as to intersect with the upper cylinder chamber 23 or the lower cylinder chamber 33, respectively. The directional cylinder chamber 43 is arranged so as to intersect the upper cylinder chamber 23 and the lower cylinder chamber 33, and a plurality of pistons are used, and a plurality of chambers and ports are provided to shorten a plurality of characteristics using the same sample. It can be easily measured in time, and simultaneous measurement such as heat conduction measurement can be performed in addition to viscosity measurement and PVT measurement.

(7) Measurement of shear viscosity As a method of measuring the viscosity of a sample, for example, first, the lower piston 31 is moved to the lowest position, and the upper piston 21 is also moved to the lowest position. A sample is put through the hole 35 (communication with the lower cylinder 32) in the upper part of the lower cylinder 32 and stored in the chamber of the lower cylinder 32. Thereafter, the lower piston 31 is moved upward, the pressure is detected by the pressure sensor 5 in the measurement flow path (slit) 11, and the upper piston 21 is linked and moved upward (the upper piston 21 and the lower piston 31 are linked). Move) and finally move to the top. At that time, there is a hole in a part of the upper cylinder chamber, and a small amount of sample and air are discharged.

  Next, the upper piston 21 and the lower piston 31 are linked and moved downward to move the sample downward in the measurement channel 11. The pressure P of the sample at each position in the measurement channel 11 at that time is measured by the pressure sensors 5, 5, and 5. The pressure difference ΔP of the sample at the spaced position of the measurement channel 11 is obtained. The flow rate Q of the sample is calculated from the shape of the measurement channel 11 and the moving speeds of the lower piston 31 and the upper piston 21.

  From the shape of the measurement channel 11 and the measured pressure P, the shear stress σ (Pa) of the sample is calculated by the following equation 1. In Formula 1, t is the thickness (mm) of the measurement flow path 11, and as an example, t = 0.4 mm. L is the distance (mm) along the measurement flow path 11 of the two pressure sensors 5, 5, and as an example, the distance L between the upper and lower pressure sensors is 30 mm. ΔP is a pressure difference (Pa) measured by a pressure sensor separated by a distance L.

The strain rate (time derivative of γ) (1 / s) is calculated by the following equation 2. In Equation 2, w is the width (mm) of the measurement channel, and as an example, w = 9 mm. Q is the flow rate of the sample (mm ³ / s).

Further, the shear viscosity η (Pas) is calculated by the following formula 3 and is obtained from the formulas 1 and 2. In this way, the shear viscosity η can be easily measured by flowing the sample through the measurement channel 11 and measuring the pressure of the sample.

Next, by simultaneously moving the upper piston 21 and the lower piston 31 upward, the upper piston 21 and the lower piston 31 can be moved in both the upward and downward directions, and the shear viscosity can be measured many times. In addition, by making the measurement channel 11 into a slit shape, the amount of sample (sample amount) can be reduced, and when the temperature is variable, the temperature rise time can be shortened, and measurement in a short time is possible. It is possible to prevent thermal degradation of the sample as much as possible. In addition, dynamic measurement is possible by controlling the temperature of the sample and the flow rate. In addition, with such a configuration, high-speed deformation can be easily performed at a strain deformation speed of up to 3000 s ⁻¹ . In addition, since an actual measurement device (unit) is very small, it can quickly respond to a temperature change and can easily change the temperature.

(8) Measurement of PVT characteristics PVT characteristics can be measured using the lateral cylinder chamber 43 and the left and right pistons 41 and 42. In order to introduce the sample into the horizontal cylinder chamber 43, first, the lower piston 31 is lowered below the horizontal cylinder chamber 43. In this state, the sample is introduced into the lateral cylinder chamber 43. At that time, the amount of the sample introduced into the lateral cylinder chamber 43 can be adjusted by the position of the lower piston 31 and the position of the upper piston 21. Further, the amount of the sample introduced into the lateral cylinder chamber 43 can be adjusted even at the distance between the left piston 41 and the right piston 42 facing each other. The amount of the sample is, for example, 0.5 cc.

When the left piston 41 and the right piston 42 are held at a predetermined interval and the left piston 41 and the right piston 42 are moved to one side in the lateral cylinder chamber 43, the state shown in FIG. In the state of FIG. 2, the left piston 41 blocks communication between the lower cylinder chamber 33 and the lateral cylinder chamber 43 and can confine a predetermined amount of sample in the lateral cylinder chamber 43. A predetermined pressure can be applied to the sample by the relative movement control of the left piston 41 and the right piston 42, and the volume of the sample can be controlled. The temperature of the sample can be controlled and the temperature can be measured. By these controls, the displacement of the piston when the temperature and pressure are changed can be measured, and the specific volume, that is, the PVT characteristic can be obtained from the displacement. As the measurement mode, it is possible to change the pressure at the same temperature (pressure change mode), change the temperature at the same pressure (temperature change mode), and the like. The sample can be measured and dynamic measurement becomes possible.

  Examples will be described below.

(1) Measuring method The sample used was isotactic polypropylene (PP) (manufactured by Idemitsu Petrochemical Co., F704NP, MI = 6.8) with clear material properties such as molecular weight, molecular weight distribution, and stereoregularity.

Viscosity can be measured easily in a relatively short time while changing the strain rate and temperature using the specific apparatus described above with reference to FIGS. The strain rate was changed from 10 to 2000 s ⁻¹ and the temperature was changed from 200 ° C. to 220 ° C. The PVT measurement was performed in a temperature change mode in which the temperature was changed from 220 ° C. to 40 ° C. under an equal pressure of 10 MPa to 150 MPa.

(2) Measurement result As a result of the measurement, the shear viscosity characteristics of the sample are shown in FIG. The horizontal axis in FIG. 4 indicates the strain rate (1 / s), and the vertical axis indicates the shear viscosity (Pas). FIG. 4 shows curves at 200 ° C. and 220 ° C. The viscosity in the strain rate region shows shearing properties, and at a high strain rate (2000 s ⁻¹ ), the viscosity difference between 200 ° C. and 220 ° C. is very small. Moreover, as a result of measuring under the same conditions with an existing capillary type viscometer (manufactured by Toyo Seiki Co., Ltd.), the same viscosity behavior was exhibited and the viscosity values were almost the same. In the 400 μm-thick measurement channel 11, it was suggested that the viscosity data is not different from the measurement data using a normal capillary die.

The result of the PVT measurement is shown in FIG. The horizontal axis in FIG. 5 represents temperature (° C.), and the vertical axis represents specific volume (cm ³ / g). FIG. 5 shows curves with pressures of 10 MPa, 50 MPa, 100 MPa, and 150 MPa. At a pressure of 10 MPa, the specific volume begins to decrease, that is, the density starts from about 130 ° C. These are density increases due to crystallization, and this temperature corresponds to the crystallization start temperature. It can be seen that as the pressure increases, the crystallization temperature shifts to the higher temperature side. This tendency is the same as the conventionally known behavior and shows the effectiveness of the sample measuring apparatus.

Thus, this sample measuring apparatus can measure shear viscosity and PVT using a small amount of sample of about 10 g.

External view of the sample measuring apparatus of the present invention Sectional view of the sample measuring apparatus of FIG. External view of measurement channel block in FIG. Shear viscosity characteristics of isotactic polypropylene (PP) Characteristic diagram of PVT measurement of isotactic polypropylene (PP)

Explanation of symbols

1 ... Measurement channel block 11 ... Measurement channel 111 / Slit gap 112 / Slit width 113 / Slit channel length 12 / Bolt 21 / Upper piston 22 / Upper cylinder 23 / Upper cylinder chamber 24 · · Flange 31 · · Lower piston 32 · · Lower cylinder 33 · · Lower cylinder chamber 34 · · Flange 35 · · Hole 41 · · Left piston 42 · · Right piston 43 · · Lateral cylinder chamber 5 · · · Pressure sensor

Claims (4)

A measurement channel through which the sample moves; and
A first cylinder chamber and a second cylinder chamber which are arranged at both ends of the measurement channel and communicate with the measurement channel;
A first piston that moves within the first cylinder chamber; a second piston that moves within the second cylinder chamber;
At least two pressure sensors arranged along the measurement channel and measuring the pressure in the measurement channel;
A third cylinder chamber communicating with the first cylinder chamber;
A third piston and a fourth piston that move in the third cylinder chamber ;
The sample in the measurement channel is pressed and moved along the measurement channel by the first piston and the second piston, the pressure of the sample in the measurement channel is measured by at least two pressure sensors ,
A sample measuring device that blocks communication between the first cylinder chamber and the third cylinder chamber by the third piston or the fourth piston and presses the sample in the third cylinder chamber by the third piston and the fourth piston . The sample measurement apparatus according to claim 1,
A sample measurement device comprising a temperature control device for controlling the temperature of the sample and a temperature measurement device for measuring the temperature . The sample measurement apparatus according to claim 1,
A sample measuring device comprising a pressure measuring device for measuring the pressure applied to the sample in the third cylinder chamber . The sample measurement apparatus according to claim 1 ,
A sample measuring device comprising a displacement measuring device for measuring the displacement of the third piston or the fourth piston.

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