JPH10122827A - Optical measuring method and optical measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and quickly determine the angular distribution dependence of the scattered light intensity of scattered light from a polymer, and particularly to easily and quickly average the dispersion particles in the polymer. Provided are an optical measurement method and an optical measurement device capable of measuring a particle diameter. The present invention relates to an optical measurement method and an optical measurement device that irradiates a polymer with intermittent light having a certain wavelength and obtains the angular distribution dependence of the scattered light intensity of the scattered light from the polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for irradiating a polymer with intermittent light having a certain wavelength and detecting the same wavelength component as the radiated light from among the scattered light from the polymer. The present invention relates to an optical measurement method and an optical measurement device for determining the angle distribution dependence of the scattered light intensity of light, and further relates to the dispersion particles present in the polymer from the angle distribution dependence of the scattered light intensity of the obtained scattered light. It is suitable for an optical measuring method and an optical measuring device for measuring the average particle diameter of the above. It is particularly suitable as a polymer for measuring the average particle diameter of a compounding additive in a polyvinyl chloride molded article, polyvinyl chloride residual particles, and the like.

[0002]

2. Description of the Related Art In general, polymer particles, especially resin moldings, contain residual particles of these polymers, compounding agents, and the like. May occur.

[0003] In particular, polyvinyl chloride obtained by the suspension polymerization method has a particle size of 100 µm or more called grain.
Sub-grains, agglomerates, primary particles, domains, and micro-domains are formed in a hierarchical particle structure from the outermost particles of 300 μm in order, and when subjected to molding, the heat history of the processing machine during molding and Finer as needed based on the shearing force history. However, particles of several μm to 0.05 μm which could not be collapsed and refined at the time of molding remain in the final molded article of polyvinyl chloride, and such residual particles act as structural defects. The final physical properties such as material strength properties may be adversely affected.

[0004] Further, the dispersion state of a polymer alloy containing different kinds of macromolecules is greatly affected by physical properties, and it is important to grasp the dispersion state. Conventionally, methods for measuring the average particle size of the dispersed particles present in these polymers include: 1) breaking the polymer molded body below the glass transition temperature of the polymer, depositing the fractured surface with platinum-palladium, After vapor deposition, the deposited film on the surface is separated from the molded body sample to make a replica consisting only of the deposited film, the replica sample is observed and photographed with a transmission electron microscope, and the result is image-analyzed to average the dispersed particles. Method for calculating particle diameter, 2) Breaking the polymer molded body below the glass transition temperature of the polymer, depositing the fractured surface with gold, observing and photographing the fractured surface with a scanning electron microscope, and imaging the result as an image Analytical method to calculate the average particle diameter of dispersed particles 3) Ultra-thin sections are cut out from a polymer molded body using a microtome, and then stained with osmium or rutenuic acid, and then transmitted electron microscope. How to calculate the average particle diameter of the dispersed particles observed and photographed the results and image analysis,
Etc. are known.

[0005]

However, in any of the above-mentioned methods, it is necessary not only to have a very high level of skill but also to go through a complicated analysis procedure, which requires a great deal of labor for the measurement. Had occurred.

SUMMARY OF THE INVENTION It is an object of the present invention to be able to easily and quickly determine the angular distribution dependence of the scattered light intensity of scattered light from a polymer, and particularly to measure the average particle diameter of polymer dispersed particles. It is an object of the present invention to provide an optical measurement method and an optical measurement device which can solve the problems of the conventional method and can easily and quickly measure the average particle diameter of dispersed particles in a polymer.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, irradiate a polymer with light and obtain the angular distribution dependence of the scattered light intensity of the scattered light after irradiation. Was found to be effective, and the present invention was completed.

That is, the present invention irradiates a polymer with intermittent light having a predetermined wavelength, detects the same wavelength component as the irradiated light from among the scattered light from the polymer, and detects the scattered light of the scattered light. It is characterized by determining the angular distribution dependence of the intensity,
Further, the present invention relates to an optical measuring method and an optical measuring device, wherein the average particle diameter of dispersed particles present in a polymer is measured from the angle distribution dependence of the scattered light intensity of the obtained scattered light.

Hereinafter, the present invention will be described in detail.

The polymer in the present invention is a general polymer, for example, a polymer, a polymer alloy or a molded product thereof, particles, powder, pellets, and a molten state. As the polymer, for example, polyvinyl chloride, ethylene-vinyl chloride copolymer,
Vinyl chloride resin such as vinyl acetate-vinyl chloride copolymer, polyolefin resin such as polyethylene, polypropylene, ethylene-propylene copolymer, ABS, SB
S, SEBS, styrene polymers such as methyl methacrylate-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, nylon-6, nylon-6
6, polyamides such as nylon-46, polyesters such as polybutylene terephthalate, polyethylene terephthalate and polyethylene naphthalate, polyphenylene sulfide, LCP and the like. Examples of the polymer alloy include polymer alloys of the above polymers, modified PPO, polyurethane-polyvinyl chloride, polybutylene terephthalate-polycarbonate, ABS-
Polycarbonate and the like can be mentioned.

The dispersed particles in the present invention are particles existing in a polymer, and include, for example, polymer particles such as undisintegrated polymer fine particles, domains due to blending of polymers, and gel components due to deterioration or the like. And compounding agents such as heat stabilizers, light stabilizers, coloring agents, and fillers.

The present invention is particularly effective for measuring the particle size of undisintegrated residual particles or compounding agents in polyvinyl chloride in which dispersed particles are likely to exist in a polymer.

The optical measuring method and the optical measuring apparatus according to the present invention will be described with reference to the light scattering measuring apparatus shown in FIGS. 1 and 2, but the present invention is not limited to those shown in the drawings. .

The apparatus shown in FIG. 1 is a side view of one example of the optical measuring apparatus of the present invention for measuring the angular distribution dependence of the scattered light intensity of the scattered light and the average particle diameter of the dispersed particles.

The apparatus shown in FIG. 2 is an upper view of an example of the optical measuring apparatus of the present invention for measuring the angular distribution dependence of the scattered light intensity of the scattered light and the average particle diameter of the dispersed particles.

In the present invention, the light irradiated to the polymer is:
This is intermittent light of a certain wavelength, and is used as intermittent light of a certain wavelength, for example, by cutting light of a certain wavelength emitted from a light source with a light chopper or the like.

In the present invention, it is preferable that intermittent light having a certain wavelength be used as needed depending on the size of the residual particles in the polymer. That is, in a polymer containing relatively large dispersed particles, using a light source of light having a constant wavelength having a long wavelength,
For a polymer containing relatively small dispersed particles, it is preferable to use a light source of light having a short wavelength and a constant wavelength. For example, the size of the dispersed particles in the polymer is 0.01 μm to 0.1 μm.
In this case, a short-wavelength laser having a wavelength of less than 0.4 μm, an excimer laser, or the like can be used as a light source. When the size of the dispersed particles is 0.1 to 10 μm, it is preferable to use a visible light source having a constant wavelength in the range of 0.4 to 0.8 μm, for example, a commercially available laser light source, A helium-neon laser (wavelength: 0.633 μm; manufactured by Uniface Co., Ltd.) can be used. When the size of the dispersed particles is 10 μm or more, an infrared laser having a wavelength of 1 μm or more, YAG
A laser or a carbon dioxide gas laser having a wavelength of 9 to 11 μm can be used as a light source. A commercially available light chopper may be used.

In the present invention, the polymer is irradiated with the above-described intermittent light having a certain wavelength, and the same wavelength component as the irradiated light is detected from among the scattered light from the polymer, whereby the scattering is performed. The angle distribution dependence of the scattered light intensity of the light can be determined, and the average particle size of the dispersed particles present in the polymer can be determined from the angle distribution dependence of the scattered light intensity of the scattered light.

In the present invention, by detecting the same wavelength component as the irradiated light from among the scattered light from the polymer, stray light due to multiple reflections in the apparatus or external light is detected as in ordinary light scattering measurement. By removing noise without being adversely affected by noise light or the like, the scattered light intensity of scattered light from only the polymer can be measured at a high S / N (signal / noise) ratio, and the measurement accuracy can be improved. . Then, in order to detect the same wavelength component as the light irradiated from the scattered light from the polymer, it is preferable to use a lock-in amplifier. For example, a lock-in amplifier manufactured by NF Circuit Design Block Co., Ltd. can be used.

In order to determine the angle distribution dependence of the scattered light intensity of the scattered light, a light receiver with a rotating table can be used. The light receiver having the scattered light intensity is, for example, a photodiode or a photomultiplier. A photomultiplier tube, a light counter, or the like can be used. When the average particle diameter of the dispersed particles in the polymer is large and the scattered light intensity is strong, a photodiode is preferable. On the other hand, when the average particle diameter of the dispersed particles in the polymer is small and the scattered light intensity is small, a photomultiplier or an optical counter is preferable. In addition, the turntable on which the optical receiver is mounted,
It is preferable that the angle can be set every 0.1 ° from 0 ° to 180 °, and a manual turntable or an automatic turntable driven by a pulse motor can be used.

In the present invention, the range of the scattering angle of the scattered light to be measured is arbitrarily determined by the target polymer or dispersed particles. For example, the primary particles of polyvinyl chloride or the aggregate thereof are 1 μm to 10 of remaining molded body
In a polymer having dispersed particles having a particle diameter of 1 μm, the angle is preferably 1 ° to 20 °, such as 0.1 μm to 1 μm, such as a molded article in which domains of polyvinyl chloride finer than the primary particles or aggregates thereof remain.
For a polymer having m dispersed particles, an angle range of 5 ° to 50 ° is preferable. Furthermore, 0.1% of a molded body or the like in which micro-domains of fine polyvinyl chloride or aggregates thereof exist.
For polymers having dispersed particles of μm to 1 μm, 30 ° to
70 ° is suitable.

In the present invention, the scattered light intensity I of the scattered light is
And the angle variable q relating to the scattering angle θ is q = (4π /
λ) sin (θ / 2), and plotting the reciprocal of the square root of the scattered light intensity I against the square of the angle variable q (hereinafter referred to as “Debye plot”; FIG. 3), thereby scattering the scattered light. The angle distribution dependence of light intensity is required.

Further, in the present invention, the average particle size of the dispersed particles in the polymer can be obtained from the intercept A and the slope B and the device constant C of the above-mentioned Debye plot according to the general formula (1). Here, the apparatus constant C can be determined by measuring using a standard sample such as polystyrene latex in which the dispersed particle diameter is clear and the dispersed particle diameter is monodisperse.

Average particle diameter of dispersed particles = C * (B / A) ^1/2 (1) In the optical measuring method and the optical measuring device according to the present invention, the angle distribution dependence of the scattered light intensity of the scattered light. Alternatively, it is preferable to use an arithmetic processing unit for obtaining the average particle diameter of the dispersed particles from the angle dependence.

[0025]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 A helium-neon laser 2a having a wavelength of 0.633 μm (trade name: HN-550P, manufactured by Nippon Kagaku Engineering Co., Ltd.) was used as a light source to convert light from the light source into light having an intermittent constant wavelength. Light chopper 5a, scattered light intensity measurement light receiver 10, lock-in amplifier 11 (manufactured by NF Circuit Design Block Co., Ltd., trade name: single-phase lock-in amplifier 5600), detector goniometer 8a
(Manufactured by Nippon Kagaku Engineering Co., Ltd.), pulse motor controller 8b for driving the goniometer (manufactured by Nippon Kagaku Engineering Co., Ltd.), quarter-wave plate 3, Gram-Thompson-type polarizing element 4, sample holding stage 6, pinhole 9 Angular distribution dependence of the scattered light intensity of the scattered light, the angle distribution dependence of the scattered light intensity of the scattered light, and the average of the dispersed particles in the polymer. An optical measuring device for particle size measurement was prepared. Here, the personal computer 12 reads the intercept and the slope when the reciprocal of the square root of the scattered light intensity I is devi-plotted with respect to the square of the angle variable q, and obtains the average of the dispersed particles from the apparatus constant C and the above equation (1). This is an arithmetic processing unit that also performs programming for calculating the particle diameter.

FIG. 1 is a side view of the optical measuring device.

FIG. 2 shows an upper view of the optical measuring device.

The device constant C of the optical measuring device determined by using polystyrene latex having an average particle size of 0.1 μm as a standard sample was 225 [nm ⁻¹ ].

Example 2 Polyvinyl chloride resin (manufactured by Taiyo PVC Co., Ltd., trade name: TH-
1000) 100 parts by weight, stabilizer (manufactured by Nitto Kasei Co., Ltd.)
N2000E) 4 parts by weight of the blended polyvinyl chloride composition were kneaded with an 8-inch test roll set at 150 ° C. for 10 minutes to obtain a 1.1 mm thick translucent plate-like molded product. This plate-like molded product was molded into a transparent plate-like molded product having a thickness of 1.0 mm using a press molding machine set at 150 ° C.

The scattered light for 10 seconds at each scatter angle was set for this plate-like molded body using the measuring apparatus of Example 1 at a scatter angle of 10 ° to 40 ° and an angle step interval of 0.5 °. The average value of the intensity was obtained, and the scattered light intensity I was obtained.

FIG. 3 shows the angle distribution dependence of the scattered light intensity of the obtained scattered light as a Debye plot of the reciprocal of the square root of the scattered light intensity I with respect to the square of the angle variable q.

The average particle diameter of the particles dispersed in the plate-like molded product was 0.43 μm, and the required work process for this measurement was 10 minutes.

Example 3 100 parts by weight of methyl methacrylate-styrene copolymer (manufactured by Nippon Steel Chemical Co., Ltd., trade name: MS-600), and methyl methacrylate-butadiene-styrene copolymer (manufactured by Nippon Synthetic Rubber Co., Ltd.) 2.5% by weight of the product (trade name # 61) was prepared in the same manner as in Example 2 to obtain a plate-like molded product.

Using the measuring apparatus of Example 1, the obtained plate-like molded body was used to measure the scattering light intensity for 10 seconds at each scattering angle with the scattering angle in the range of 15 ° to 40 ° and the angle step interval of 1 °. An average was obtained, and a scattered light intensity of 1 was obtained.

FIG. 3 is a Debye plot of the reciprocal of the square root of the scattered light intensity I with respect to the square of the angle variable q.

This plate-like molded product had an average particle size of 0.31 μm.
m of methyl methacrylate-butadiene-styrene copolymer particles were dispersed therein, and the required operation process for this measurement was 10 minutes.

Comparative Example 1 An ultrathin section sample was cut out from the plate-like molded product obtained in Example 2 using a microtome, stained with rutenic acid for 24 hours, and the sample was scooped up with a copper mesh and observed with a transmission electron microscope. And took a picture. The photograph is converted to an image analyzer (trade name TVIP-, manufactured by Nippon Avionics Co., Ltd.).
4100) and the analysis software "Image Command 41"
Image analysis was performed using 98 ″ to calculate the average particle size of the dispersed particles.

The average particle size of the particles dispersed in the plate-like molded product was 0.45 μm, and the required operation process for this measurement was 3 days.

[0040]

According to the present invention, the dependence of the intensity of scattered light on the angular distribution and the average particle size of the dispersed particles in the polymer can be measured simply, quickly and accurately.

[Brief description of the drawings]

FIG. 1 is a side view of an optical device according to the present invention.

FIG. 2 is a top view of an optical device according to the present invention.

FIG. 3 is a Debye plot of the reciprocal of the square root of the scattered light intensity I with respect to the square of the angle variable q showing the angular distribution dependence of the scattered light intensity of the scattered light obtained in Example 2 and Example 3.

[Explanation of symbols]

1: Optical bench 2a: Helium-neon laser 2b: Stabilized power supply for laser output 3: Quarter-wave plate 4: Gram-Thompson-type polarizing element 5a: Light chopper (frequency 280 Hz) 5b: Light chopper frequency controller 6: Sample Holding stage 7: Sample 8 a: Goniometer for rotating the receiver 8 b: Pulse motor controller for driving the goniometer 9: Pinhole 10: Receiver for measuring scattered light intensity 11: Lock-in amplifier 12: Personal computer for measurement control and data analysis 13 : Scattering angle θ 14: Square root of reciprocal of scattering intensity I 15: Square of angle variable q

Claims (5)

[Claims] 1. A polymer is irradiated with intermittent light having a certain wavelength,
An optical measurement method comprising detecting a component having the same wavelength as that of light irradiated from among scattered light from a polymer, and determining an angle distribution dependency of a scattered light intensity of the scattered light. 2. The optical system according to claim 1, wherein the average particle size of the dispersed particles present in the polymer is determined from the angular distribution dependence of the scattered light intensity of the scattered light according to claim 1. Measuring method. 3. The method according to claim 1, wherein the polymer is a molded article of polyvinyl chloride, and the dispersed particles are residual particles of polyvinyl chloride contained in the molded article of polyvinyl chloride and / or a compounding agent. 3. The optical measurement method according to 1 or 2. 4. A light source for emitting light of a certain wavelength to determine the angular distribution dependence of the scattered light intensity of the scattered light, a light chopper for converting incident light from the light source to intermittent light of a certain wavelength, and a polymer. An optical measuring device comprising a light scattering measuring device for detecting, with a lock-in amplifier, the same wavelength component as that cut by a light chopper among scattered lights from the light source. 5. The apparatus according to claim 4, further comprising an arithmetic processing unit for obtaining an average particle diameter of the dispersed particles present in the polymer from the dependence of the intensity of the scattered light on the angular distribution. Optical measuring device.