JP2652338B2 - Method and apparatus for measuring pressure-volume-temperature characteristics of solidified material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pressure-volume-temperature characteristic (hereinafter referred to as P
It is called VT characteristics. The present invention relates to a method and an apparatus for measuring a thermosetting or thermoplastic synthetic resin, and particularly for measuring by an indirect method in which measurement is performed using a sample cell. And a method and apparatus.

[0002]

2. Description of the Related Art In research and development of three-dimensional woven fabric composite materials, etc., evaluation of PVT characteristics during curing of an epoxy resin used as a matrix is expected to provide important knowledge in optimizing a molding process. Although it can be done, there is no report on the PVT characteristics of the material that does not proceed with the curing reaction, because there is more difficulty with the measuring device and the measuring method due to the curing. Therefore, not only the epoxy resin, but also the PV
In order to know the T characteristic, it is necessary to develop a measuring means.

[0003] An apparatus for measuring the PVT characteristics of a material using a sample cell by an indirect method has been reported by Sato et al. There are reports (Ogisawa, 177 pages of proceedings of the 3rd Annual Meeting of the Japan Society of Plastics Processing). The sample cell in these devices encloses a single sample to be measured or a small liquid (for example, mercury) with a known compressibility and the sample, and uses the bellows to expand or contract the change in cell volume at the expected temperature and pressure. It was made measurable. The sample cell in the former device measures the increase in the internal volume of the cell as the extension of the bellows, and the sample cell in the latter device measures the increase in the internal volume of the cell as the contraction of the bellows. Also in this case, the tip of the rod attached to the movable part of the bellows is connected to the core of the differential transformer, and the displacement is measured.

When such an apparatus is used for measurement of PVT characteristics of a material which undergoes a curing reaction, such as a thermoplastic resin, which is solidified by cooling, or a thermosetting synthetic resin, the inner wall of a sample cell is required. After the resin is solidified or hardened, the resin solidifies, causing distortion and a change in the specific volume due to the Poisson effect, so that not only is it difficult to accurately measure the PVT characteristics, but also the sample cell There is a possibility that the cell cannot be reused or the cell is damaged.

[0005]

SUMMARY OF THE INVENTION The technical problem of the present invention is to provide a means for measuring the above-mentioned fearless PVT characteristics, and more specifically, even after the material to be measured has solidified. Without any distortion in it,
Accordingly, it is an object of the present invention to provide a method and an apparatus for measuring PVT characteristics, which enable accurate measurement of PVT characteristics and facilitate reuse of a sample cell.

[0006]

According to the method for measuring PVT characteristics of the present invention for solving the above-mentioned problems, basically, a sample which solidifies in a measurement process and a liquid having a small compressibility are placed in a sample cell. When measuring the pressure-volume-temperature characteristics from the change in the cell volume at the intended temperature and pressure, enclose the sample in a sample cell by enclosing the sample with a flexible polymer film. It is a feature. In the above method, the sample to be measured can be sealed in a bag made of a flexible polymer film and directly stored in the sample cell. Further, in the above method, the sample is accommodated in the cup portion of the sample capsule, a flexible polymer film sufficient to encapsulate the sample inside the cup portion is interposed, and then the cup portion is The cap portion is attached with a gap therebetween, and can be loaded into the sample cell.

On the other hand, a measuring apparatus according to the present invention for solving the above-mentioned problems includes a sample cell for enclosing a sample to be measured and a liquid having a small compressibility, and a change in the cell volume at a desired temperature and pressure. A measuring device for measuring pressure-volume-temperature characteristics, wherein a bag made of a flexible polymer film for sealingly storing a sample to be measured is provided in the sample cell. It is. In addition, the above-described measuring apparatus is configured such that a sample capsule for accommodating a sample to be measured is loaded in a sample cell, and the capsule is attached to the cup portion and the cup portion with a gap therebetween. A cap formed with a communication passage inside and outside of the capsule, and a cap formed by covering the cup with a flexible polymer film sufficient to cover a sample inside the cup. can do.

[0008]

In the above-described method and apparatus, the sample which is solidified in the measurement process is wrapped in a flexible polymer film or sealed with a bag made of the film, and the sample is put in the sample cell together with a liquid having a low compressibility. And the pressure-volume-temperature characteristics are measured from the change in the cell volume at the desired temperature and pressure. Even if the sample is solidified from a liquid state in the measurement process (the molten resin is solidified by cooling in the case of a thermoplastic resin, and cured by a reaction in the case of a thermosetting resin), it does not adhere to the inner wall of the sample cell, Since the specific volume does not change due to the Poisson effect due to distortion, accurate PVT characteristics can be measured, and the sample can be taken out of the sample cell while being covered with the flexible polymer film. Cell reuse is also facilitated.

When a sample is accommodated in a sample capsule and loaded into a sample cell, the sample is sealed in the sample cell because a flexible polymer film is provided on the cup portion of the capsule. Even if the sample floats upward due to the buoyancy of the liquid having a large specific gravity, the sample is not fixed to the sample cell or the inner wall of the capsule because it is covered by the flexible polymer film. for that reason,
Even if the sample solidifies from the liquid state in the measurement process, the specific volume does not change due to the distortion and the Poisson effect, enabling accurate measurement of PVT characteristics. Can be taken out of the capsule while being encapsulated, so that the sample cell and the capsule can be easily reused.

[0010]

FIG. 1 shows a first embodiment of a PVT characteristic measuring apparatus according to the present invention. This measuring device is for measuring the PVT characteristics of the solidified material from the change in the cell volume under the desired temperature and pressure conditions.
A sample cell 2 for enclosing a liquid having a higher specific gravity than the sample to be measured and a sample such as mercury and having a low compressibility is provided therein. The pressure vessel 1 has a pressure inlet 3 connected to a plunger pump 4 for maintaining the inside of the sample cell 2 in a pressurized state, and the pressure detected by a pressure sensor is fed back to the plunger pump 4 to control the pressure. A heating device 5 is provided around the pressure vessel 1 so as to be controllable and to control temperature conditions inside the pressure vessel 1.

The sample cell 2 has a cylindrical body 6 for accommodating therein a bag 16 made of a flexible polymer film containing a sample 25 to be measured and mercury 26 with a lid 8 closed. At the same time, the lower end is closed by the bellows 9, and the rod 10 connected to the movable part of the bellows 9 is led out downward, and the tip of the rod 10 is connected to the core 12 of the differential transformer 11 attached to the lower part of the pressure vessel 1. In this connection, the expansion and contraction displacement of the bellows 9 is measured as a change in the internal volume of the sample cell 2 due to the displacement of the core 12.

In order to detect the internal temperature of the pressure vessel 1, a thermocouple 15 inserted from above the pressure vessel 1 is connected to a pipe 13 erected at the center of the upper lid 8 of the sample cell 2.
, And the tip is brought into contact with the upper packing 14 in the lid 8. The sample cell 2
And the displacement of the core of the differential transformer are respectively recorded by a recorder and taken into a computer for analysis.

As shown in FIG. 2A, the bag 16 of the flexible polymer film can have an extremely general shape. Since it is desirable not to leave air inside, a shape having a narrower mouth portion is more preferable as illustrated in FIG. In addition, the opening of the bag 16 may be sealed by heat sealing, or by a chuck or any other method capable of maintaining airtightness.
Furthermore, the flexible polymer film may be a film that encloses the sample 25 without leaking without using it as a bag.

When the sample resin is a thermoplastic resin, the flexible polymer film has a melting point equal to or higher than the melting point of the sample resin, and is desirably the highest temperature among the intended measurement temperatures. A material having the above melting point is used. Also, when the sample resin is a thermosetting resin, it is preferable to use a material having a melting point higher than the highest temperature among the measurement temperatures, but until the time when the curing reaction of the resin proceeds and becomes infusible. Any material having a melting point that does not melt can be used without any problem.

Examples of the material of the flexible polymer film include polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, ethylene tetrafluoride hexafluoropropylene copolymer, and ethylene tetrafluoride perfluoroalkyl vinyl ether copolymer. Thermosetting resins such as polyimide and polyetherimide can be used in addition to thermoplastic resins such as coalescing, 6-nylon and 6,6-nylon.
The thickness of the flexible polymer film is not particularly limited,
Since it is desirable that the weight of the film is light,
mm or less is desirable. More preferably, it is 0.05 mm or less, and still more preferably 0.025 mm or less.

In the measuring device having the above configuration, P
When measuring the VT characteristics, first, a liquid sample 25 such as a thermosetting resin that is solidified in the measurement process is sealed with a bag 16 made of a flexible polymer film, or wrapped with the film, and To load. Next, the sample cell 2 is filled with the mercury 26 by sealing the other portions except for the inlet of the mercury 26 formed by the pipe 13 at the center of the lid 8. In this case, since the sample 25 is covered with the flexible polymer film, it does not adhere to the inner wall of the sample cell 2.

The sample cell 2 is set in a PVT measuring device after sealing the mercury inlet with an upper packing 14, and is heated at a desired temperature controlled by a heating device 5 and controlled by a plunger pump 4. The change in the internal volume of the sample cell 2 at the initial pressure is defined as
Differential transformer 1 through rod 10 attached to bellows
The specific volume of the sample 25 is measured by detecting the vertical displacement of the core 12, thereby measuring the PVT characteristics of the sample.

In the measurement process, when the sample is a thermoplastic resin, the sample is repeatedly melted and solidified every time the temperature of the sample exceeds the melting point, and when the sample is a thermosetting resin, the sample reacts at the curing temperature. However, even if such a sample is cured, it is encapsulated in the flexible polymer film and does not adhere to the inner wall of the sample cell 2, so that the cured sample has distortion. Does not occur and the specific volume does not change,
Accurate measurement of PVT characteristics becomes possible. Further, since the sample 25 can be taken out of the sample cell 2 while being covered with the flexible polymer film, the sample cell can be easily reused.

FIGS. 3 and 4 show the PVT of the first embodiment.
A second embodiment in which a sample capsule 20 for accommodating a sample 25 to be measured is used in a characteristic measuring apparatus is shown. This sample capsule 20
Consists of a cup portion 21 and a cap portion 22, which are formed of a thin metal, and a portion of the cap portion 22 (three places at equal intervals around the inside) is cut and raised inward to form an elastic protruding portion 23.
Is formed, and the elastic projection 23 is pressed against the peripheral surface of the cup 21 so that the cap 22 is
Is provided with a gap 24 interposed therebetween to secure a communication path inside and outside the capsule.

When this capsule 20 is used, FIG.
As shown in FIG. 7, a sample 25 is poured into the cup portion 21 and covered with the flexible polymer film 17 made of the above-mentioned material, and then the cap portion 22 is applied to encapsulate the sample. The capsule 20 is configured such that the edge of the cap portion 22 is engaged with the locking portion 7 on the inner surface of the cylindrical body 6 of the sample cell 2.
And loaded in the sample cell 2. The configuration and operation of the PVT characteristic measuring apparatus according to the second embodiment are the same as those according to the first embodiment except for the above-described points, and thus the same reference numerals are given and the description thereof is omitted.

In the capsule 20, the cup 2
1 is covered with a flexible polymer film 17, and the cap portion 2
2, the sample 25 accommodated in the cup 21 floats from the cup 21 due to buoyancy at the time of injecting the mercury 26 into the sample cell 2.
As shown in FIG. 3, it is wrapped in the polymer film 17 and does not flow out into the cap part 22 or the sample cell 2 of the capsule. Therefore, the specific volume does not change due to distortion in the cured sample, and accurate PV
It becomes possible to measure the T characteristic. According to this, FIG.
As shown in FIG.
When covering the sample 1, it is necessary to provide a margin so that the polymer film 17 can be encapsulated without substantially fixing the entire sample 25 to the capsule 20 in a state where the mercury 26 is injected as shown in FIG. There is.

[0022]

According to the method and apparatus for measuring PVT of the present invention described in detail above, the sample is covered with the flexible polymer film, so that even after the material to be measured is solidified, It will not be distorted, which will allow accurate measurement of PVT characteristics and facilitate the reuse of sample cells.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a PVT characteristic measuring apparatus according to the present invention.

FIGS. 2A and 2B are perspective views of a bag used in the PVT characteristic measuring device.

FIG. 3 is a sectional view showing a second embodiment of the PVT characteristic measuring device according to the present invention.

FIG. 4 is a sectional view of a capsule used in the PVT characteristic measuring device of the second embodiment.

[Explanation of symbols]

 2 sample cell 16 bag 17 flexible polymer film 20 capsule 21 cup part 22 cap part 24 gap 25 sample 26 mercury

Claims (5)

(57) [Claims] In a sample cell, a sample to be solidified in a measurement process and a liquid having a low compressibility are sealed, and a desired temperature,
In measuring the pressure-volume-temperature characteristic from the change in the cell internal volume due to the pressure, the sample is encapsulated by a flexible polymer film and housed in a sample cell. A method for measuring pressure-volume-temperature characteristics. 2. The method according to claim 1, wherein the sample to be measured is sealed in a bag made of a flexible polymer film and directly stored in a sample cell.
A method for measuring pressure-volume-temperature characteristics of a solidified material. 3. A sample cell which is solidified in a measurement process and a liquid having a higher specific gravity and a lower compressibility than the sample are sealed in a sample cell. -When measuring the temperature characteristics, the sample is accommodated in a cup portion of a sample capsule, and a flexible polymer film sufficient to encapsulate the sample inside the cup portion is interposed on the cup portion, A method for measuring pressure-volume-temperature characteristics of a solidified material, comprising: attaching a cap portion to a cup portion with a gap therebetween; and loading the cap portion into the sample cell. 4. A measuring apparatus comprising a sample cell for enclosing a sample to be measured and a liquid having a low compressibility, and measuring a pressure-volume-temperature characteristic from a change in the cell volume at a desired temperature and pressure. A device for measuring pressure-volume-temperature characteristics of a solidified material, wherein a bag made of a flexible polymer film for sealingly storing a sample to be measured is provided in the sample cell. 5. A pressure-volume-temperature characteristic comprising a sample cell for enclosing a sample to be measured and a liquid having a higher specific gravity and a lower compressibility than the sample, and a change in the cell volume at a desired temperature and pressure. In the measuring device for measuring the above, a sample capsule for accommodating a sample to be measured is loaded into the sample cell, and the capsule is attached to the cup portion and the cup portion with a gap therebetween. And a cap portion forming a communication passage between the inside and outside of the capsule. The cap portion was attached to the cup portion by interposing a flexible polymer film sufficient to encapsulate the sample inside the cup portion. An apparatus for measuring pressure-volume-temperature characteristics of a solidified material.