JPH10282088A - Method for measuring extent of gelation of polyvinyl chloride and residual grain size distribution - Google Patents

Abstract

PROBLEM TO BE SOLVED: To establish a method for measuring the extent of gelation of polyvinyl chloride and the residual grain size distribution conveniently and quantitatively without requiring skill for any worker by imparting a dynamical stimulus to the polyvinyl chloride. SOLUTION: A test piece produced by admixing polyvinyl chloride resin with a thermal stabilizer is imparted continuously and periodically with a dynamical stimulus at eight constant interval points for 1 Log using a viscoelasticity measuring unit in order to determine the modulus of elasticity and the loss tangent thereof at 170 deg.C, 0.01 Hz and the inclination of logarithmic plot of frequency-elasticity at 170 deg.C. Activation energy of the modulus of elasticity is also determined from the measurements of viscoelasticity. The measurements are substituted into expression I (G is the modulus of elasticity of a sample), expression II (T is the loss tangent of the modulus of elasticity of a sample), expression III (K is the inclination of logarithmic plot of frequency-elasticity of a sample) and expression IV (E is the activation energy of the modulus of elasticity of a sample) thus determining the extent of gelation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the degree of gelation of polyvinyl chloride and the distribution of residual particle diameters using a mechanical stimulus represented by a viscoelasticity measurement method.

[0002]

2. Description of the Related Art Polyvinyl chloride obtained by a general suspension polymerization method as a method for producing polyvinyl chloride is composed of sub-grains, agglomerates, and primary particles in the order of 100 μm to 300 μm outermost particles called grains. It is composed of a hierarchical particle structure including particles, domains, and microdomains. When it is subjected to molding, it is refined as needed by the history of heat and the shearing force of a processing machine during molding. However, in the final molded product of polyvinyl chloride, several μm
Particles of ~ 0.05 μm remain, and such residual particles cause an increase in the elastic modulus and melt viscosity during the molding process, and not only overload the processing machine, but also cause poor appearance of the molded product, Since the molded product that has been cooled and solidified acts as a structural defect, it may adversely affect final physical properties such as material strength characteristics of the molded product.

As a method of evaluating the gelation degree of polyvinyl chloride, 1) a polyvinyl chloride resin compound being formed is touched by hand, and the gelation degree is empirically evaluated based on the degree of elasticity. Method 2) Method of immersing the molded body in a solvent such as acetone and judging by the degree of holding of the shape of the molded body. 3) Melting of crystallites of polyvinyl chloride by DSC method. A method of calculating the degree of gelation from the relative amount ratio of the heat of fusion of unmelted microcrystals, and the like are known.

[0004]

However, each of the methods 1) and 2) is an extremely abstract evaluation scale, and it is necessary to express not only the problem that the evaluation order differs depending on the operator but also specific numbers. Can not do
There were problems with reproducibility and reliability. On the other hand, in the method 3), if the gelation has not progressed much, the amount of the recrystallized microcrystals is too small, and if the gelation has progressed extremely, the amount of the unmelted microcrystals is too small. And the resolution is poor.

An object of the present invention is to provide an elastic modulus, a loss tangent of elastic modulus, a frequency dependence of elastic modulus, and / or an elastic modulus of polyvinyl chloride obtained by using a mechanical stimulus represented by a viscoelasticity measuring method. The present invention provides a method for easily measuring the gelation degree and the residual particle size distribution of polyvinyl chloride from the activation energy and the like.

[0006]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, the results obtained by mechanical stimulation represented by a viscoelasticity measuring method have shown that the degree of gelation of polyvinyl chloride and The present inventors have found that they correspond well to the residual particle size distribution, and have completed the present invention.

That is, the present invention relates to a measuring method characterized by determining the degree of gelation or the distribution of the residual particle size by applying a mechanical stimulus to polyvinyl chloride.

Hereinafter, the present invention will be described in more detail.

The degree of gelation of polyvinyl chloride referred to in the present invention means that the undisintegrated or unmelted residual particles of polyvinyl chloride become smaller or smaller as kneading proceeds during the molding and processing of polyvinyl chloride. Say something about. In general, it is empirically known that polyvinyl chloride increases the gelling temperature as the molding temperature increases if the molding method is the same.

[0010] The term "remaining particle size distribution of polyvinyl chloride" as used in the present invention refers to the particle size distribution of polyvinyl chloride particles which remain undisintegrated or unmelted even when polyvinyl chloride is subjected to molding. .

In the present invention, the mechanical stimulus may be one generally known as a mechanical stimulus in measurement.
A typical example is mechanical stimulation by a viscoelasticity measurement method. The application form of the mechanical stimulus is arbitrary, and examples thereof include a shear vibration mode, a compression vibration mode, and an extension vibration mode.

In the present invention, the elastic modulus, the loss tangent of the elastic modulus, and the frequency of the elastic modulus of the polyvinyl chloride are measured to give a mechanical stimulus to the polyvinyl chloride and measure the gelation degree or the residual particle size distribution of the polyvinyl chloride. In order to obtain the dependence, the activation energy of the elastic modulus, and the like, it is also possible to use either a prototype or a commercially available viscoelasticity measuring device. Examples of commercially available viscoelasticity measuring devices include a viscoelasticity measuring device (trade name: MR500) manufactured by Rheology Co., Ltd.
A viscoelasticity measuring device (trade name: ARES) manufactured by Scientific Inc. is exemplified.

In order to carry out the measuring method of the present invention, a mechanical stimulus for obtaining the elastic modulus of elasticity of polyvinyl chloride, loss tangent of elastic modulus, frequency dependence of elastic modulus, activation energy of elastic modulus, etc. It is preferable to make the device not to slip between the polyvinyl chloride sample and the measuring jig when giving the value.
As a method of preventing the slip, for example, a method of pressing the sample with a constant stress during the measurement, a method of cutting a groove in the surface of the measurement jig, and the like can be mentioned.

The first measuring method of the present invention is a method for measuring the degree of gelation of polyvinyl chloride by applying a mechanical stimulus to the polyvinyl chloride. Here, the information used to measure the degree of gelation of polyvinyl chloride includes the elastic modulus of the polyvinyl chloride obtained by applying a mechanical stimulus to the polyvinyl chloride, the loss tangent of the elastic modulus, and the frequency of the elastic modulus. Dependency and activation energy of the elastic modulus can be cited.

In the present invention, the degree of gelation of polyvinyl chloride can be measured from the elastic modulus of the polyvinyl chloride obtained by applying a mechanical stimulus to the polyvinyl chloride. Here, since the elastic modulus of polyvinyl chloride to a mechanical stimulus has a tendency to decrease as gelation proceeds, it is possible to calculate the gelation degree of polyvinyl chloride from the magnitude of the elastic modulus. . The method of calculating the degree of gelation of the polyvinyl chloride is arbitrary, but as a simple method, for example, a sample in which the degree of gelation is changed in a wide range is prepared, and a mechanical stimulus is given to each sample, and The upper limit of the elastic modulus obtained by measuring the elastic modulus of the sample was determined to be 0% for the degree of gelation, and the lower limit elasticity was set to 100% for the degree of gelation. Method. In this method, the measured upper limit elastic modulus value (hereinafter, referred to as Gmax) is set to a gelling degree of 0%, and the lower limit elastic modulus value (hereinafter, referred to as Gmin) is set to a gelling degree of 10.
By setting it to 0%, it becomes possible to measure the degree of gelation of polyvinyl chloride as a relative evaluation by percentage according to the following formula (1).

Gelation degree (%) = (G−Gmin) / (Gmax−Gmin) × 100 (1) (where G represents the elastic modulus of the measurement sample.) The elastic modulus of polyvinyl chloride is , Obtained by dividing the response to a mechanical stimulus given to polyvinyl chloride by the strain to the stimulus.

In the present invention, when measuring the degree of gelation of polyvinyl chloride, the elastic modulus obtained from the mechanical stimulus is used in order to remove the influence of the thickness of the measurement sample and obtain a highly accurate measurement. Is preferably used.
Here, since the loss tangent of the elastic modulus of polyvinyl chloride to a mechanical stimulus tends to increase as gelation proceeds, the gelation degree of polyvinyl chloride is calculated from the magnitude of the loss tangent of the elastic modulus. It is possible to do. The method of calculating the degree of gelation of the polyvinyl chloride is arbitrary, but as a simple method, for example, a sample in which the degree of gelation is changed in a wide range is prepared, and a mechanical stimulus is given to each sample, and The loss tangent of the modulus of elasticity of the sample was measured. The loss tangent of the upper limit of the loss tangent of the elastic modulus obtained was 100% of the gelation degree, and the loss tangent of the lower limit of the elasticity was 0% of the gelation degree.
As a method, a method of calculating the degree of gelation using the loss tangent of the elastic modulus therebetween as a relative percentage is exemplified. In the method, the measured loss tangent value of the upper limit elastic modulus (hereinafter, Tma
It is called x. ) Is taken as the gelation degree of 100%, and the loss tangent value of the lower elastic modulus (hereinafter referred to as Tmin) is taken as the gelation degree of 0%.
Thus, the gelation degree of polyvinyl chloride can be measured as a relative evaluation by percentage according to the following equation (2).

Gelation degree (%) = (T−Tmin) / (Tmax−Tmin) × 100 (2) (where T represents the loss tangent of the elastic modulus of the measurement sample.) The loss tangent of the modulus of elasticity is obtained as the ratio of the storage modulus to the loss modulus obtained by applying periodic mechanical stimulation to polyvinyl chloride.

Further, in the present invention, in order to improve the measurement accuracy of the gelation degree of polyvinyl chloride, the frequency dependence of the elastic modulus obtained by applying different periodic mechanical stimuli to polyvinyl chloride is determined. Preferably, it is used. Here, as the frequency dependence of the elastic modulus, for example, a slope of a graph of a logarithmic plot of the frequency of the mechanical stimulus applied to the measurement sample and the obtained elastic modulus as shown in FIG. 1 can be used. Since the inclination tends to increase as the gelation of polyvinyl chloride proceeds, the gelation degree of polyvinyl chloride can be calculated from the magnitude of the frequency dependence of the elastic modulus.

The method of calculating the gelation degree of the polyvinyl chloride is arbitrary, but the frequency of the mechanical stimulus and the slope of the logarithmic plot of the obtained elastic modulus are used as the frequency dependence of the elastic modulus. If you have, as a simple way,
For example, a sample in which the degree of gelation is changed in a wide range is prepared, different periodic mechanical stimuli are applied to each sample, and the slope of a logarithmic plot of frequency-elastic modulus of each sample (frequency dependence of elastic modulus). The gelation degree can be calculated by setting the upper limit slope value of the slope obtained by measuring the gelation degree to 100% and the lower limit slope value to 0% gelation degree, and the slope between them as a relative percentage. In this method, the measured upper limit slope value (hereinafter, referred to as Kmax) is defined as 100% gelling degree, and the lower limit slope value (hereinafter, referred to as Kmin) is defined as 0% gelling degree. This allows the degree of gelation of polyvinyl chloride to be measured as a percentage relative evaluation.

Gelation degree (%) = (K−Kmin) / (Kmax−Kmin) × 100 (3) (where K represents the slope of a logarithmic plot of frequency-elastic modulus of the measurement sample) In, for example, when measuring the degree of gelation of polyvinyl chloride compounded with fillers such as fillers, except for the influence on the elastic modulus of the fillers and the like, measure the degree of gelation with high measurement accuracy Therefore, it is preferable to determine the degree of gelation from the activation energy of the elastic modulus. Here, the activation energy of the elastic modulus is obtained from the frequency dependence and the temperature dependence of the elastic modulus obtained by applying a mechanical stimulus to, for example, polyvinyl chloride under different frequency and temperature conditions as follows. You can ask. FIG. 1 shows an example of a plot of the frequency dependence of the elastic modulus. FIG. 2 shows an example of the temperature dependence of the elastic modulus in which the shift amount and the reciprocal of the measured temperature obtained from FIG. 1 are plotted. First, the frequency dependence of the elastic modulus shown in FIG. 1 is obtained by measuring the frequency dependence of the elastic modulus at regular temperature intervals, for example, every 10 ° C. Then, focusing on the elastic modulus at an arbitrary frequency measured at the second highest temperature of the measurement result, the elastic modulus value is shifted in the frequency direction so as to overlap the result of the next highest measurement temperature after the measurement temperature. This operation is sequentially performed from the high temperature side to determine the shift amount. By plotting the shift amount against the reciprocal of the absolute temperature, the temperature dependence of the elastic modulus shown in FIG. 2 can be obtained.
Then, the activation energy can be obtained from the slope by the following (4).

Activation energy (J / mol / K) = Slope × Gas constant (J / mol / K) ÷ Ln10 (4) Here, the activation energy of the elastic modulus changes with the progress of gelation of polyvinyl chloride. Because it tends to be smaller,
The gelation degree of polyvinyl chloride can be calculated from the activation energy of the elastic modulus. The method of calculating the degree of gelation of the polyvinyl chloride is arbitrary, but as a simple method, for example, a sample in which the degree of gelation is changed in a wide range is prepared, and a mechanical stimulus is given to each sample, and The activation energy of the elastic modulus of the sample was measured, and the activation energy at the upper limit of the activation energy of the elastic modulus obtained was defined as the degree of gelation of 0%, and the activation energy at the lower limit was defined as the degree of gelation of 100%. A method of calculating the degree of gelation using the activation energy of the ratio as a relative percentage is exemplified. In this method, the measured activation energy value of the upper limit elastic modulus (hereinafter, referred to as Emax) is defined as the degree of gelation of 0%, and the activation energy value of the lower limit elastic modulus (hereinafter, referred to as Emin) is defined as the degree of gelation. By setting it to 100%, it becomes possible to measure the degree of gelation of polyvinyl chloride as a percentage relative evaluation by the following equation (5).

Gelation degree (%) = (E−Emin) / (Emax−Emin) × 100 (5) (where E represents the activation energy of the elastic modulus of the measurement sample.) In the measurement method, the activation energy of the elastic modulus required by applying a mechanical stimulus to the polyvinyl chloride under different frequency and temperature conditions is different from the activation energy obtained by the mechanical stimulus on the lower frequency side. The second embodiment of the present invention is based on the frequency-dependent waveform of the activation energy of the elastic modulus, since the activation energy obtained by the mechanical stimulation on the side is more sensitive to the residual particles having a large particle diameter in the polyvinyl chloride. The particle size distribution of the residual particles in the polyvinyl chloride according to the invention can be determined.

In the present invention, the frequency of the different periodic mechanical stimuli to be applied when the mechanical stimulus is applied to the polyvinyl chloride to measure the gelling degree or the residual particle size distribution of the polyvinyl chloride is different from that of the polyvinyl chloride. It is also possible to use differently depending on the difference in gelation. When the residual particle diameter in polyvinyl chloride is relatively large, it is preferable to apply a mechanical stimulus having a small frequency to determine the elastic modulus. As the method, for example, the size of the residual particle size in polyvinyl chloride is estimated in advance by observation with an electron microscope or the like, and when the size of the residual particle size in polyvinyl chloride is in the range of 0.1 to 1 μm, It is preferable to measure the elastic modulus by applying a mechanical stimulus in the range of 10 ^-3 to 10 ^-1 Hz. On the other hand, the size of the residual particle diameter in polyvinyl chloride is 0.01 to 0.1 μm
If the range of, it is preferable to measure the elastic modulus gives mechanical stimulation range frequency of 10 ^-1 ~10 ² Hz.

In the measuring method of the present invention, the temperature at which a mechanical stimulus is applied to the polyvinyl chloride to measure the gelling degree or the residual particle size distribution of the polyvinyl chloride is not particularly limited as long as it does not deviate from the object of the present invention. It is not limited. Then, since there is no problem of deterioration of polyvinyl chloride during the measurement, and particularly stable measurement becomes possible, the
The measurement is preferably performed at 230 ° C., particularly preferably as close to the molding temperature as possible.

The polyvinyl chloride to be measured by the measuring method of the present invention is generally known as polyvinyl chloride, for example, vinyl chloride homopolymer, ethylene-vinyl chloride copolymer, vinyl acetate-chloride. Examples of the method include a vinyl copolymer, and the measurement method of the present invention is particularly suitable as a method for measuring polyvinyl chloride obtained by a suspension polymerization method. Further, various compounding agents such as a heat stabilizer, a lubricant, an antioxidant, and an ultraviolet absorber may be added to polyvinyl chloride.

Further, the measuring method of the present invention is applied to a general polyvinyl chloride molding machine such as a calender molding machine, an extrusion cast molding machine, a profile extrusion molding machine, a pipe molding machine, an injection molding machine and the like. Equipped as a special function of the molding machine, and used as an in-line automatic inspection system for the degree of gelation or residual particle size distribution at the time of forming and processing of polyvinyl chloride, thereby performing the molding of polyvinyl chloride while performing quality control It is also possible.

[0028]

EXAMPLES The measuring method of the present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Reference Example 1 Polyvinyl chloride (trade name: TH70, manufactured by Taiyo PVC Co., Ltd.)
0) 3 parts by weight of a heat stabilizer (trade name: T157, manufactured by Dainippon Ink Co., Ltd.) were added to 100 parts by weight,
1, 2, 5, 1 with an 8-inch test roll set to temperature conditions of 150 ° C., 150 ° C., 170 ° C., 190 ° C., and 200 ° C.
By kneading for 0 and 15 minutes, a plate-shaped molded body having a thickness of 1.1 mm under each kneading condition was obtained. However, 1
Under a kneading condition of 30 ° C. for 1 minute, a plate-like molded body could not be obtained. Further, at 210 ° C. or more, if kneaded for 1 minute or more, deterioration of polyvinyl chloride was observed, so that a plate-like molded product could not be obtained. Then, the obtained plate-like molded body was formed into a plate-like molded body having a thickness of 1.0 mm using a press machine to obtain a test piece.

Each of the obtained test pieces was subjected to a viscoelasticity measuring device (manufactured by Rheometric Scientific Co., Ltd.).
Temperature 170, 180, 190 using the trade name ARES)
° C, 1 Log at a frequency of 0.01 Hz to 15.5 Hz
The frequency dependence of the elastic modulus and the loss tangent of the elastic modulus were measured by continuously applying eight periodic mechanical stimuli at equal intervals.

From this measurement, the modulus of elasticity, the loss tangent of the modulus of elasticity at 170 ° C. and 0.01 Hz, the slope of the logarithmic plot of frequency-elasticity at 170 ° C., and the activation energy of each test piece were measured. I asked.

Here, since no test piece was obtained under the kneading conditions of 130 ° C. for 1 minute, the elasticity obtained by setting the degree of gelation of the test piece under the kneading conditions of 130 ° C. for 2 minutes to 0% was obtained. The modulus is defined as the upper limit elastic modulus value (Gmax), the elastic loss tangent is defined as the lower elastic modulus tangent value (Tmin), the slope is defined as the lower slope value (Kmin), and the activation energy is defined as the upper activation energy value (Emax). did. In addition, since the elastic modulus, the loss tangent of the elastic modulus, the slope, and the activation energy obtained from all the test pieces under the kneading conditions of 200 ° C. had the same values, the test pieces under the kneading conditions of 200 ° C. were gelated. By setting the degree of conversion to 100%, the obtained elastic modulus is reduced to a lower limit elastic modulus value (Gm
in), the loss tangent of the elastic modulus was defined as the loss tangent value (Tmax) of the upper elastic modulus, the slope was defined as the upper slope value (Kmax), and the activation energy was defined as the lower activation energy value (Emin).

Table 1 shows the upper and lower limits of the elastic modulus, the upper and lower limits of the loss tangent of the elastic modulus, the upper and lower limits of the slope, and the upper and lower limits of the activation energy. Is shown.

Example 1 Polyvinyl chloride resin (trade name: TH7, manufactured by Taiyo PVC Co., Ltd.)
100 parts by weight, 3 parts by weight of a heat stabilizer (trade name: T157, manufactured by Dainippon Ink Co., Ltd.) was added,
The mixture was kneaded with an 8-inch test roll set at a temperature of 10 ° C. for 10 minutes to obtain a transparent plate-shaped molded product having a thickness of 1.1 mm. The transparent plate-like molded body was formed into a 1.0 mm-thick transparent plate-like molded body using a press machine set at 170 ° C. to obtain a test piece.

The test piece was subjected to a viscoelasticity measuring device (ARES, manufactured by Rheometric Scientific Co., Ltd.).
At a temperature of 170, 180, 190 ° C. and a frequency of 0.0
By continuously providing eight periodic mechanical stimuli at equal intervals for 1 Log between 1 Hz to 15.5 Hz,
The frequency dependence of the elastic modulus and the loss tangent of the elastic modulus were measured.

From this measurement, the elastic modulus, the loss tangent of the elastic modulus at 170 ° C. and 0.01 Hz of each test piece, and the slope of the logarithmic plot of frequency-elastic modulus at 170 ° C. were determined. Are shown in Table 1.

The activation energy of the elastic modulus was determined by the following procedure using the measurement results of the viscoelasticity. FIG.
In the results of the elastic modulus measurement at 180 ° C. shown in FIG. 6, the frequency of interest, the elastic modulus at 0.01 Hz is shifted in the horizontal direction so as to overlap the viscoelastic curve at 190 ° C., and the shift amount is calculated. The elastic modulus of 0.011 Hz is shifted in the horizontal direction so as to overlap the previously shifted viscoelastic curve at 180 ° C., and the shift amount is obtained. Then, the obtained shift amount is plotted with respect to the reciprocal of the absolute temperature as shown in FIG. 2, and the activation energy for the frequency of interest is obtained from the above equation (4) from the slope. The frequency of interest for these operations was changed from 0.01 Hz to 1 Hz, and the activation energy for each frequency of interest was determined. Table 2 shows the activation energy of the elastic modulus at 0.01 Hz.

FIG. 3 shows the frequency dependence of the elastic modulus at 170 ° C.

FIG. 4 shows the frequency dependence of the activation energy.

These measurement results are calculated by the above equation (1),
Table 2 shows the gelation degree obtained by substituting (2), (3) and (5).

The frequency dispersion of the activation energy shown in FIG. 4 corresponds to the particle size and amount of the particles remaining in the polyvinyl chloride. Here, the low frequency side corresponds to the amount of the residual particles having a large particle diameter, and the high frequency side corresponds to the amount of the residual particles having a small particle diameter. In this example, since the average residual particle size is large, the frequency corresponding to the residual particle having the maximum frequency particle size is out of the measurement range, and thus the bottom of the residual particle size distribution is visible. The average particle diameter of the residual particles obtained by measuring the test piece with a scanning electron microscope was 360 nm.
Met.

Example 2 A resin composition having the same composition as in Example 1 was kneaded with an 8-inch test roll set at 180 ° C. for 10 minutes, and the thickness was 1.1 m.
m was obtained. 180 ° C
1.0mm thick using a press molding machine set to
Was obtained as a test piece.

Then, the same measurement as in Example 1 was performed.
The obtained measurement results are shown in FIGS.

Table 2 shows the gelation degree obtained by the same method as in Example 1.

Further, in the frequency dispersion of the activation energy shown in FIG. 4, the tail is visible because the average particle diameter of the residual particles is large, but the particle diameter is smaller than that in Example 1 and a peak is seen on the low frequency side. The average particle diameter of the remaining particles has been decreasing. The average particle size of the residual particles obtained by measurement with a scanning electron microscope was 210 nm.

Example 3 A resin composition having the same composition as in Example 1 was kneaded with an 8-inch test roll set at 190 ° C. for 10 minutes, and the thickness was 1.1 m.
m was obtained. This plate-like molded body is heated at 190 ° C.
1.0mm thick using a press molding machine set to
Was obtained as a test piece.

Then, the same measurement as in Example 1 was performed.
The obtained measurement results are shown in FIGS.

Table 2 shows the gelation degree obtained by the same method as in Example 1.

Further, the peak of the frequency dispersion of the activation energy shown in FIG. 4 starts to be seen on the low frequency side, and the size thereof is smaller than those of the first and second embodiments. The particle size is small and the amount is small. The average particle size of the residual particles obtained by measuring with a scanning electron microscope was 190 nm.

Reference Example 2 Polyvinyl chloride (manufactured by Taiyo PVC Co., Ltd., trade name: TH70)
0) 100 parts by weight of heat stabilizer (Nitto Kasei Co., Ltd.)
(Trade name: TVS8901) 3 parts by weight, internal lubricant (Henkel Hakusui Co., Ltd., product name Roxyol GH4) 2 parts by weight, external lubricant (Hoechst Co., Ltd., product name Hostalab)
0.3 parts by weight and 0.1 part by weight of an outer lubricant (trade name: Hi-wax 200PF, manufactured by Mitsui Petrochemical Co., Ltd.)
1, 2, 5, 1 with an 8-inch test roll set to temperature conditions of 0 ° C., 150 ° C., 170 ° C., 190 ° C., and 200 ° C.
By kneading for 0 and 15 minutes, a plate-shaped molded body having a thickness of 1.1 mm under each kneading condition was obtained. However, 1
Under a kneading condition of 30 ° C. for 1 minute, a plate-like molded body could not be obtained. Further, at 210 ° C. or more, if kneaded for 1 minute or more, deterioration of polyvinyl chloride was observed, so that a plate-like molded product could not be obtained. Then, the obtained plate-like molded body was formed into a plate-like molded body having a thickness of 1.0 mm using a press machine to obtain a test piece.

The same measurement as in Reference Example 1 was performed on this sample, and the elastic modulus, the loss tangent, the slope of a logarithmic plot of frequency-elastic modulus, and the maximum and minimum values of the activation energy were obtained.
Table 3 shows this value. When the composition is changed, the values of the elastic modulus, the loss tangent, and the slope of the logarithmic plot of the frequency-elastic modulus change greatly, whereas the maximum value and the minimum value of the activation energy hardly change.

Example 4 Polyvinyl chloride (trade name: TH70, manufactured by Taiyo PVC Co., Ltd.)
0) 100 parts by weight of heat stabilizer (Nitto Kasei Co., Ltd.)
3 parts by weight (trade name TVS8901), 2 parts by weight of an internal lubricant (trade name: Roxyol GH4, manufactured by Henkel Hakusui Co., Ltd.), external lubricant (trade name: Hostalab, manufactured by Hoechst Co., Ltd.)
0.3 parts by weight and 0.1 part by weight of an outer lubricant (trade name: Hi-wax 200PF, manufactured by Mitsui Petrochemical Co., Ltd.)
The mixture was kneaded with an 8-inch test roll set at 0 ° C. for 5 minutes to obtain a translucent plate-shaped molded product having a thickness of 1.1 mm. The translucent plate-shaped molded body was formed into a 1.0 mm-thick translucent plate-shaped molded body using a press machine set at 150 ° C. to obtain a test piece.

Then, the same measurement as in Example 1 was performed.
Table 3 shows the obtained measurement results.

Table 4 shows the gelation degree obtained by the same method as in Example 1.

Example 5 A resin composition having the same composition as in Example 4 was kneaded with an 8-inch test roll set at 170 ° C. for 5 minutes, and the thickness was 1.1 mm.
Was obtained. The translucent plate-like molded product was
1.0 mm thick using a press machine set at 0 ° C
And a test piece was obtained.

Then, the same measurement as in Example 1 was performed.
Table 3 shows the obtained measurement results.

Table 4 shows the gelation degree obtained by the same method as in Example 1.

[0058]

[Table 1]

[0059]

[Table 2]

[0060]

[Table 3]

[0061]

[Table 4]

[0062]

The measurement method of the present invention does not require any skill by any worker, and can easily and quantitatively measure the gelation degree and the residual particle size distribution of polyvinyl chloride.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for obtaining activation energy of an elastic modulus, and is an example of a result obtained by measuring a frequency dependence of an elastic modulus at each temperature.

FIG. 2 is an explanatory diagram of an operation for obtaining activation energy of an elastic modulus, and is an example in which a shift amount is plotted with respect to a reciprocal of a temperature.

FIG. 3 is an example of the result of measuring the frequency dependence of the elastic modulus of polyvinyl chloride.

FIG. 4 is an example of frequency dependence of activation energy of elastic modulus.

Claims (5)

[Claims] 1. A method for measuring the degree of gelation of polyvinyl chloride, wherein the degree of gelation is determined by applying a mechanical stimulus to the polyvinyl chloride. 2. A method for measuring the degree of gelation of polyvinyl chloride, wherein the degree of gelation is determined from an elastic modulus or a loss tangent of the elastic modulus obtained by applying a mechanical stimulus to the polyvinyl chloride. 3. The method according to claim 1, wherein the degree of gelation is determined from the frequency dependence of the elastic modulus obtained by applying mechanical stimuli of different frequencies to polyvinyl chloride. A method for measuring the degree of gelation of vinyl chloride. 4. A gelling degree is obtained from activation energy of an elastic modulus obtained from a temperature dependence of an elastic modulus obtained by applying a mechanical stimulus to polyvinyl chloride under different temperature conditions. A method for measuring the degree of gelation of polyvinyl chloride according to claim 1. 5. The residual particle size distribution based on the frequency dependence of the activation energy of the elastic modulus obtained from the temperature dependence of the elastic modulus obtained by applying a mechanical stimulus to polyvinyl chloride under different frequency and temperature conditions. A method for measuring the distribution of residual particle diameters in vinyl chloride, characterized by determining the particle size distribution.