JP7589575B2 - Quality control method for polymeric material, manufacturing method for resin composition, and quality control method for cable or tube - Google Patents

Description

The present invention relates to a polymeric material and a quality control method thereof, a method for producing a resin composition, a cable or tube and a quality control method thereof, and factory automation or a factory automation robot.

Conventionally, cables are known that use polyester elastomers containing organic high molecular weight silicone polymers as the material for the insulation that covers the outer periphery of the conductor (see Patent Document 1). According to the cable described in Patent Document 1, silicone has low affinity with other substances, prevents adhesion between surfaces, and provides releasability, which improves the surface slippage between the insulated core wires. When the cable is subjected to stress such as bending or twisting, the twisted insulated core wires can move smoothly relative to each other, which ultimately contributes to improving the bending and twisting life. Furthermore, by improving the slippage between the insulated core wires, the flexibility of the cable itself can also be improved.

In addition, polyester elastomers containing organic high molecular weight silicone polymers are less expensive than fluororesins such as ethylene tetrafluoroethylene (ETFE), which have traditionally been used as insulating materials with excellent surface slipperiness, helping to reduce cable manufacturing costs.

JP 2008-218061 A

However, when silicone is blended with a polymeric material such as polyester elastomer, the silicone content of the blended polymeric material may not match the blending ratio of the raw materials, and the desired slipperiness may not be obtained. For this reason, it is desirable to evaluate the actual slipperiness of the surface of an insulator that uses a polymeric material containing silicone.

The object of the present invention is to provide a quality control method for polymeric materials that can evaluate the surface slipperiness of polymeric materials that contain silicone as a lubricant, a method for producing a resin composition that utilizes this quality control method for polymeric materials, a cable or tube and a quality control method thereof, and factory automation or a factory automation robot.

The present invention aims to solve the above problems by providing a quality control method for a polymeric material, comprising a measurement step of irradiating a polymeric material containing silicone as a lubricant with a laser and measuring the Raman spectrum, and an evaluation step of evaluating the lubricity of the surface of the polymeric material based on the intensity of the peak in the Raman spectrum that is attributable to molecular vibrations derived from the silicone.

The present invention also aims to solve the above problems by providing a quality control method for a cable or tube having an insulator made of a polymeric material containing silicone as a lubricant, the method evaluating the lubricity of the surface of the insulator using the above-mentioned quality control method for polymeric materials.

In order to solve the above problems, the present invention also provides a method for producing a resin composition, which comprises forming a resin composition using a polymeric material containing silicone as a lubricant, the surface slipperiness of which has been evaluated by the above-mentioned method for quality control of polymeric materials.

In addition, in order to solve the above-mentioned problems, the present invention provides a polymeric material made of polyethylene containing silicone as a lubricant, which satisfies at least one of the following conditions: a first condition that, in a Raman spectrum obtained by irradiating a laser, the ratio of the peak height of a first peak attributed to Si-O stretching vibration of the silicone to the peak height of a third peak attributed to _CH2 rolling vibration of the polyethylene is 0.043 or more; a second condition that the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more; a third condition that the ratio of the peak height of a second peak attributed to C-Si-C stretching vibration of the silicone to the peak height of the third peak is 0.014 or more; and a fourth condition that the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more.

In order to solve the above problems, the present invention also provides a cable or tube equipped with an insulator made of the above polymer material.

In order to solve the above problems, the present invention also provides a factory automation or a factory automation robot equipped with the above cable or tube.

The present invention provides a quality control method for polymeric materials that can evaluate the surface slipperiness of polymeric materials that contain silicone as a lubricant, a method for producing a resin composition that utilizes this quality control method for polymeric materials, a cable or tube and a quality control method thereof, and factory automation or a factory automation robot.

FIG. 1 is a radial cross-sectional view of a cable for an FA robot, which is an example of a cable according to the present embodiment. FIG. 2 is a graph showing the Raman spectra of polyethylene containing no silicone and polyethylene containing silicone added at levels ranging from 0.99 to 6.54 wt %. Fig. 3(a) is a graph showing an enlargement of the vicinity of peak A1 and peak A2 in the Raman spectrum shown in Fig. 2. Fig. 3(b) is a graph showing an enlargement of the vicinity of peak A3 in the Raman spectrum shown in Fig. 2. 4A is a graph showing the relationship between the ratio of the peak height of peak A1 to the peak height of peak A3 (peak height ratio) and the concentration of silicone added. FIG. 4B is a graph showing the relationship between the ratio of the integrated intensity of peak A1 to the integrated intensity of peak A3 (integral intensity ratio) and the concentration of silicone added. 5A is a graph showing the relationship between the ratio of the peak height of peak A2 to the peak height of peak A3 (peak height ratio) and the concentration of silicone added. FIG. 5B is a graph showing the relationship between the ratio of the integrated intensity of peak A2 to the integrated intensity of peak A3 (integral intensity ratio) and the concentration of silicone added. Fig. 6(a) is a graph showing the relationship between the peak height ratio of peak A1 and the surface static friction coefficient of polyethylene to which 0 to 6.54 mass % of silicone has been added, measured under temperature conditions of 25° C., 50° C., and 75° C. Fig. 6(b) is a graph in which the range of peak height ratios of 0 to 0.2 in Fig. 6(a) is enlarged, and includes a straight line showing 0.351, which is the static friction coefficient of ETFE, measured under a temperature condition of 25° C. Fig. 7(a) is a graph showing the relationship between the integrated intensity ratio of peak A1 and the static friction coefficient of the surface of polyethylene to which 0 to 6.54 mass % of silicone has been added, measured under temperature conditions of 25° C., 50° C., and 75° C. Fig. 7(b) is a graph in which the range of integrated intensity ratios of 0 to 0.4 in Fig. 7(a) is enlarged, and includes a straight line showing 0.351, which is the static friction coefficient of ETFE, measured under a temperature condition of 25° C. Fig. 8(a) is a graph showing the relationship between the peak height ratio of peak A2 and the surface static friction coefficient of polyethylene to which 0 to 6.54 mass % of silicone has been added, measured under temperature conditions of 25° C., 50° C., and 75° C. Fig. 8(b) is a graph in which the range of peak height ratios of 0 to 0.08 in Fig. 8(a) is enlarged, and includes a straight line showing 0.351, which is the static friction coefficient of ETFE, measured under a temperature condition of 25° C. Fig. 9(a) is a graph showing the relationship between the integrated intensity ratio of peak A2 and the static friction coefficient of the surface of polyethylene to which 0 to 6.54 mass % of silicone has been added, measured under temperature conditions of 25° C., 50° C., and 75° C. Fig. 9(b) is a graph in which the range of integrated intensity ratios of 0 to 0.08 in Fig. 9(a) is enlarged, and includes a straight line showing 0.351, which is the static friction coefficient of ETFE, measured under a temperature condition of 25° C.

[Embodiment]
(Quality control method for polymeric materials)
Polymer materials such as polyester elastomers containing silicone as a lubricant have excellent surface slip properties and can be used, for example, as insulating materials for cables or tubes used in factory automation (FA), FA robots, medical ultrasound probes, etc.

The quality control method for polymeric materials according to this embodiment uses Raman scattering measurement to enable evaluation of the surface slipperiness in a non-destructive, non-contact manner while preserving the original state of the polymeric material.

The quality control method for polymeric materials according to this embodiment includes, for example, a measurement step of irradiating a polymeric material containing silicone as a lubricant with a laser and measuring the Raman spectrum, and an evaluation step of evaluating the lubricity of the surface of the polymeric material based on the intensity of the peak in the Raman spectrum that is attributed to molecular vibration derived from silicone. Here, the intensity of the peak in the Raman spectrum in this embodiment means the peak height or integrated intensity.

The slipperiness of the surface of a polymeric material depends on the concentration of silicone, and the intensity of the peaks in the Raman spectrum attributable to molecular vibrations derived from silicone changes depending on the silicone content of the polymeric material, so the slipperiness of the surface of the polymeric material can be evaluated based on this intensity. In particular, the peak attributable to the Si-O stretching vibration of silicone (referred to as the first peak) and the peak attributable to the C-Si-C stretching vibration of silicone (referred to as the second peak) are easy to read as changing in intensity depending on the silicone content of the polymeric material, so in the above evaluation process, it is preferable to evaluate the slipperiness of the surface of the polymeric material based on at least one of the intensity of the first peak and the intensity of the second peak.

The first peak is a peak having a maximum intensity in the range of 460 cm ^-1 to 520 cm ^-1 in the Raman spectrum. The second peak is a peak having a maximum intensity in the range of 700 cm ^-1 to 720 cm ^-1 in the Raman spectrum. The positions of the first and second peaks may shift within the above wavenumber range depending on the temperature of the polymer material during measurement.

If the polymeric material contains contaminants containing Si, such as mud, the intensity of the first or second peak described above may increase due to the Si contained in the contaminant, and the slipperiness of the surface of the polymeric material may not be accurately evaluated. Even in this case, it is unlikely that both the first and second peaks will change depending on the amount of Si contained in the contaminant, so by making an evaluation based on both the first and second peaks, the slipperiness of the surface of the polymeric material according to the silicone content can be accurately evaluated.

In addition, by investigating in advance the correlation between the intensity of the peaks attributable to molecular vibrations derived from silicone, such as Si-O stretching vibrations and C-Si-C stretching vibrations, and the concentration of silicone in the polymer material, it is possible to determine the specific concentration of silicone in the polymer material from the intensity of the peaks attributable to molecular vibrations derived from silicone.

In addition, when the polymer material is polyethylene, in the above evaluation step, as a criterion for the intensities of the first and second peaks, for example, a peak (referred to as the third peak) attributable to the _CH2 rolling vibration of polyethylene, among the peaks attributable to molecular vibrations derived from the polyethylene base material, can be used. That is, the slipperiness of the surface of the polymer material can be evaluated based on at least one of the ratio of the intensity of the first peak to the intensity of the third peak in the Raman spectrum and the ratio of the intensity of the second peak to the intensity of the third peak. The third peak has a maximum intensity in the range of 1150 cm ^-1 to 1200 cm ^-1 .

Specifically, for example, when evaluating the slipperiness of the surface of a polymeric material based on the intensity of the first peak, the slipperiness of the surface of the polymeric material can be evaluated based on at least one of the results of whether the ratio of the peak height of the first peak to the peak height of the third peak is 0.043 or more, and whether the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more.

The inventors have confirmed that when the ratio of the peak height of the first peak to the peak height of the third peak is 0.043 or more, or when the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more, the static friction coefficient of the surface of polyethylene (25-50°C) as a polymer material is equal to or less than the static friction coefficient of the surface of ETFE (25°C), and excellent slip properties are exhibited.

When evaluating the slipperiness of the surface of a polymeric material based on the intensity of the second peak, the slipperiness of the surface of the polymeric material can be evaluated based on at least one of the results of whether the ratio of the peak height of the second peak to the peak height of the third peak is 0.014 or more, and whether the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more.

The inventors have confirmed that when the ratio of the peak height of the second peak to the peak height of the third peak is 0.014 or more, or when the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more, the static friction coefficient of the surface of polyethylene (25-50°C) as a polymer material is equal to or less than the static friction coefficient of the surface of ETFE (25°C), and excellent slip properties are exhibited.

Here, the integrated intensity and peak height of the first to third peaks are calculated using a peak profile obtained by fitting analysis using statistical distribution functions such as a Pseudo-Voigt function, a Lorentz function, and a Gaussian distribution function, and are obtained after background correction of the peak profile. The background correction is performed to remove the influence of background thought to be caused by unavoidable light such as emitted fluorescence, Rayleigh and Mie scattered light originating from the irradiated laser light, and disturbing light other than the irradiated laser light, which is not caused by the molecular structure of the polymer material and silicone, and is performed by subtracting the background profile (baseline) obtained by fitting analysis using a polynomial function, a spline function, etc. from the above-mentioned peak profile. The integral range when calculating the integrated intensity of the first to third peaks is the range between the two intersection points of the above-mentioned peak profile and the background profile.

The ratio of the peak height of the first peak to the peak height of the third peak, the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak, the ratio of the peak height of the second peak to the peak height of the third peak, and the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak each reach their upper limit when silicone is added to the polymer material up to the limit.

In the Raman scattering measurement in the quality control method of the polymer material according to the present embodiment, the spot diameter of the laser irradiated on the surface of the polymer material is the measurement area, so that evaluation can be performed within a micro area with a diameter of 1 μm or less (for example, 0.4 to 1.0 μm). In other words, not only average information on the magnitude of the silicone concentration of the polymer material, but also information for each micro area can be obtained. Therefore, for example, it is possible to clarify the disproportionation state due to the aggregation of silicone in the polymer material, and it is possible to manage the quality of the polymer material to a higher degree. Note that the aforementioned value is not the limit value for the laser spot diameter. In principle, the laser spot diameter is determined by the wavelength of the laser light source and the numerical aperture of the objective lens. Therefore, when a Raman spectroscopic analysis is performed on the polymer material according to the present embodiment using a laser with a shorter wavelength and an objective lens with a larger numerical aperture, it becomes possible to measure even smaller micro areas of less than 0.4 μm.

(Polymer materials)
According to the present embodiment, a polymer material having excellent surface slipperiness can be provided by selecting a polymer material having excellent surface slipperiness from polymer materials whose surface slipperiness has been evaluated by the above-mentioned quality control method for polymer materials.

The polymeric material according to the present embodiment is, for example, a polymeric material made of polyethylene containing silicone as a lubricant, and satisfies at least one of the following conditions in a Raman spectrum obtained by irradiating a laser: a first condition that the ratio of the peak height of the first peak to the peak height of the third peak is 0.043 or more; a second condition that the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more; a third condition that the ratio of the peak height of the second peak to the peak height of the third peak is 0.014 or more; and a fourth condition that the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more.

(Quality control method for cables or tubes)
According to this embodiment, as a quality control method for a cable or tube having an insulation made of a polymeric material containing silicone as a lubricant, a method for evaluating the lubricity of the surface of the insulation can be provided by the above-mentioned quality control method for the polymeric material.

This cable or tube quality control method makes it possible to control the quality of cables or tubes for which surface smoothness is important, such as cables or tubes used in factory automation, factory automation robots, medical ultrasound probes, etc.

Figure 1 is a radial cross-sectional view of a cable 1 for an FA robot, which is an example of a cable according to this embodiment. The cable 1 includes a linear conductor 10 covered with multiple insulators 11, a pressure winding tape 12 wrapped around the conductor 10 covered with a bundle of multiple insulators 11, a braided shield 13 provided around the pressure winding tape 12, and a sheath 14 provided around the braided shield 13.

The conductor 10 is made of a conductor such as copper. The number of conductors 10 included in the cable 1 is not particularly limited and is set appropriately depending on the application of the cable 1. As described above, the insulator 11 is made of a polymer material containing silicone as a lubricant. The pressure winding tape 12 is made of a resin tape or the like. The braided shield 13 is made of a braided conductor or the like. The sheath 14 is made of polyvinyl chloride (PVC) or the like.

If the surface of the insulator 11 has excellent slipperiness, the insulator 11 can move easily inside the cable 1, which increases the resistance of the insulator 11 to bending and twisting of the cable 1 and also increases the flexibility of the cable 1.

When diagnosing insulation exposed on the surface of a cable or tube (e.g., insulation 11 exposed from the end of cable 1), the cable or tube can be set in the Raman scattering measurement device in its original state and measurements can be performed non-destructively. When diagnosing insulation not exposed on the surface of a cable or tube, for example, the cable or tube is cut open and measurements are performed.

In addition, by using a gun-type Raman scattering measurement device that allows the laser irradiation part and scattered light receiving part to be freely moved, it is possible to measure cables or tubes in their original state, even if the cables or tubes are difficult to measure using normal measurement devices, such as unprocessed long cables or tubes.

(cable or tube)
According to this embodiment, it is possible to provide a cable or tube having an insulator made of the above-mentioned polymer material and having an excellent surface slipperiness of the insulator. This cable or tube can be obtained by selecting a cable or tube having an excellent surface slipperiness of the insulator from cables or tubes whose surface slipperiness of the insulator has been evaluated by the above-mentioned cable or tube quality control method. Also, this cable or tube can be obtained by forming an insulator using a polymer material having an excellent surface slipperiness selected from polymer materials whose surface slipperiness has been evaluated by the above-mentioned polymer material quality control method.

The cable or tube according to this embodiment is, for example, a polymeric material made of polyethylene containing silicone as a lubricant, and is provided with an insulator made of a polymeric material that satisfies at least one of the following conditions: a first condition that the ratio of the peak height of the first peak to the peak height of the third peak in a Raman spectrum obtained by irradiating a laser is 0.043 or more; a second condition that the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more; a third condition that the ratio of the peak height of the second peak to the peak height of the third peak is 0.014 or more; and a fourth condition that the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more.

(Devices and systems equipped with cables or tubes)
According to this embodiment, it is possible to provide devices and systems such as FA, FA robots, and medical ultrasonic probes, which are provided with the above-mentioned cable or tube having an insulating surface with excellent slipperiness.

(Method for producing resin composition)
According to an embodiment of the present invention, a resin composition can be produced by using a polymer material whose quality has been controlled by the above-mentioned quality control method for a polymer material. According to this method for producing a resin composition, a polymer material having excellent surface slip properties can be selected and used as a material for the resin composition.

The form of the resin composition is not particularly limited as long as it contains a polymeric material, and can be applied to, for example, fibers made of polymeric material woven into fibers made of thread-like materials processed and molded from transition elements, precious metals such as gold, silver, and platinum, and carbon, or to films made of polymeric material laminated on a base material made of a material with a large coefficient of friction, such as ceramics or metal materials that are subject to significant wear during sliding.

(Effects of the embodiment)
According to the above embodiment, by using Raman scattering measurement, it is possible to evaluate the slipperiness of the surface of a polymer material containing silicone as a lubricant and to control its quality. In addition, it is possible to evaluate the slipperiness of the surface of an insulator made of a polymer material containing silicone as a lubricant, such as a cable or tube, and to control its quality. In addition, it is possible to manufacture a resin composition containing a polymer material having excellent surface slipperiness by utilizing this quality control method for polymer materials.

In addition, by implementing quality control of this polymer material and cable or tube, it is possible to provide a polymer material with excellent surface slipperiness, a cable or tube with an insulator with excellent surface slipperiness, and even factory automation or a factory automation robot equipped with the cable or tube.

The quality control method for polymer materials, the quality control method for cables or tubes, and the manufacturing method for resin compositions according to the above-mentioned embodiments can also be applied to material development using materials informatics (MI), which analyzes data using machine learning, artificial intelligence (AI), etc.

In addition, similar to the quality control method for polymeric materials according to the above embodiment, Raman scattering measurement can also be used to control the quality of polymeric materials to which fine particles made of fluororesins such as PTFE or fine particles made of inorganic substances such as oxides and metals have been added and dispersed, and silicone slipping layers such as silicone rubber with fine particles containing Si dispersed therein.

A sheet of polyethylene was prepared as a polymeric material containing silicone as a lubricant, and Raman scattering measurements were performed. The Raman scattering measurements were performed using Nanophoton's RAMANforce Standard VIS-NIR-HS under the following measurement conditions: laser wavelength 532 nm, spectrometer entrance slit width 50 μm, diffraction grating groove count 300 gr/mm, ND filter laser maximum light amount to attenuated light amount ratio (attenuation ratio) 250/255, objective lens magnification, numerical aperture (NA), and theoretical measurement diameter 5 times, 0.15, and 2.2 μm, respectively, and counting time 1 second x 20 cycles. The Raman scattering measurements were performed in an environment with a temperature of 20°C (average value of two-point measurements in the analysis room), a humidity of 28 RH% (average value of three-point measurements in the analysis room), and normal pressure (so-called atmospheric pressure).

2 is a graph showing Raman spectra of polyethylene containing no silicone and polyethylene containing silicone added at 0.99 to 6.54 mass %. In this Raman spectrum, peak A1 having a maximum intensity in the range of 460 cm ^-1 to 520 cm ^-1 is a peak assigned to the Si-O stretching vibration of silicone, peak A2 having a maximum intensity in the range of 700 cm ^-1 to 720 cm ^-1 is a peak assigned to the C-Si-C stretching vibration of silicone, and peak A3 having a maximum intensity in the range of 1150 cm ^-1 to 1200 cm ^-1 is a peak assigned to the _CH2 rocking vibration of polyethylene.

Figure 3(a) is a graph showing an enlargement of the vicinity of peak A1 and peak A2 in the Raman spectrum shown in Figure 2. As shown in Figures 2 and 3(a), the intensity of both peak A1, which is assigned to the Si-O stretching vibration of silicone, and peak A2, which is assigned to the C-Si-C stretching vibration of silicone, increases with increasing silicone addition concentration. Figure 3(b) is a graph showing an enlargement of the vicinity of peak A3 in the Raman spectrum shown in Figure 2.

Figure 4(a) is a graph showing the relationship between the ratio of the peak height of peak A1 to the peak height of peak A3 (peak height ratio) and the concentration of silicone added. Figure 4(b) is a graph showing the relationship between the ratio of the integrated intensity of peak A1 to the integrated intensity of peak A3 (integral intensity ratio) and the concentration of silicone added.

The following Table 1 shows the peak height ratio and integrated intensity ratio of peak A1 for each concentration of silicone added, which are related to the numerical values of each plot point in Figures 4(a) and (b), as well as the peak height and integrated intensity of peak A1 and peak height and integrated intensity of peak A3 for each concentration of silicone added, which were used to calculate them.

Figure 5(a) is a graph showing the relationship between the ratio of the peak height of peak A2 to the peak height of peak A3 (peak height ratio) and the concentration of silicone added. Figure 5(b) is a graph showing the relationship between the ratio of the integrated intensity of peak A2 to the integrated intensity of peak A3 (integral intensity ratio) and the concentration of silicone added.

The following Table 2 shows the peak height ratio and integrated intensity ratio of peak A2 for each concentration of silicone added, which are related to the numerical values of each plot point in Figures 5(a) and (b), as well as the peak height and integrated intensity of peak A2 and peak height and integrated intensity of peak A3 for each concentration of silicone added, which were used to calculate them.

Figure 6(a) is a graph showing the relationship between the peak height ratio of peak A1 and the surface static friction coefficient of polyethylene containing 0 to 6.54 mass% silicone, measured under temperature conditions of 25°C, 50°C, and 75°C.

Figure 7(a) is a graph showing the relationship between the integrated intensity ratio of peak A1 and the surface static friction coefficient for polyethylene containing 0 to 6.54 mass% silicone, measured under temperature conditions of 25°C, 50°C, and 75°C.

Figure 8 (a) is a graph showing the relationship between the peak height ratio of peak A2 and the surface static friction coefficient for polyethylene containing 0 to 6.54 mass% silicone, measured under temperature conditions of 25°C, 50°C, and 75°C.

Figure 9 (a) is a graph showing the relationship between the integrated intensity ratio of peak A2 and the surface static friction coefficient for polyethylene containing 0 to 6.54 mass% silicone, measured under temperature conditions of 25°C, 50°C, and 75°C.

Here, the method for measuring the static friction coefficients in Figures 6(a), 7(a), 8(a), and 9(a) will be described. These static friction coefficients were measured using a friction and wear tester based on Orientec's "EMF-3-F," in accordance with a test method conforming to Japanese Industrial Standard JIS K 7218. The measurement format was ring-on-ring (circular sliding with ring-shaped samples in contact with each other), and the radius "r" of the ring-shaped sample was 11.4 mm. The measurement conditions were a load "W" of 0.8 kgw, a rotational peripheral speed of 10 mm/s, and a test time of 1 min.

Then, "F" (torque) was measured at a point where the distance "R" from the center of the ring-shaped sample was 100 mm, and the friction coefficient at the time when the maximum force F (maximum torque) was measured during the test time was defined as the "static friction coefficient μ." The formula used to derive the static friction coefficient μ is shown below as Equation 1.

The following Table 3 shows the relationship between the peak height ratio and integrated intensity ratio of peak A1, the peak height ratio and integrated intensity ratio of peak A2, and the static friction coefficient measured under temperature conditions of 25°C, 50°C, and 75°C, which relate to the numerical values of each plot point in Figures 6(a), 7(a), 8(a), and 9(a).

Figure 6(b) is a graph in which the range of peak height ratios from 0 to 0.2 in Figure 6(a) is enlarged, and includes a straight line indicating 0.351, which is the static friction coefficient of ETFE measured under a temperature condition of 25°C. As shown in Figure 6(b), the static friction coefficient of silicone-containing polyethylene decreases as the temperature decreases, and when the peak height ratio of peak A1 is approximately 0.043 or more, the static friction coefficient of silicone-containing polyethylene at 50°C or less becomes equal to or less than the static friction coefficient of ETFE at 25°C.

Figure 7(b) is a graph that expands the range of integrated intensity ratios from 0 to 0.4 in Figure 7(a), and includes a straight line indicating 0.351, which is the static friction coefficient of ETFE measured under temperature conditions of 25°C. As shown in Figure 7(b), the static friction coefficient of silicone-containing polyethylene decreases as the temperature decreases, and when the integrated intensity ratio of peak A1 is approximately 0.1 or more, the static friction coefficient of silicone-containing polyethylene at 50°C or less becomes equal to or less than the static friction coefficient of ETFE at 25°C.

Figure 8(b) is a graph enlarging the range of peak height ratios from 0 to 0.08 in Figure 8(a), and includes a straight line indicating 0.351, which is the static friction coefficient of ETFE measured under a temperature condition of 25°C. As shown in Figure 8(b), the static friction coefficient of silicone-containing polyethylene decreases as the temperature decreases, and when the peak height ratio of peak A2 is approximately 0.014 or more, the static friction coefficient of silicone-containing polyethylene at 50°C or less becomes equal to or less than the static friction coefficient of ETFE at 25°C.

Figure 9(b) is a graph showing an enlarged range of the integrated intensity ratio of 0 to 0.08 in Figure 9(a), including a straight line indicating 0.351, which is the static friction coefficient of ETFE measured under a temperature condition of 25°C. As shown in Figure 9(b), the static friction coefficient of silicone-containing polyethylene decreases as the temperature decreases, and when the integrated intensity ratio of peak A2 is approximately 0.011 or more, the static friction coefficient of silicone-containing polyethylene at 50°C or less becomes equal to or less than the static friction coefficient of ETFE at 25°C.

(Summary of the embodiment)
Next, the technical ideas grasped from the above-described embodiment will be described by using the reference numerals and the like in the embodiment. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiment.

[1] A quality control method for a polymeric material, comprising: a measuring step of irradiating a polymeric material containing silicone as a lubricant with a laser and measuring the Raman spectrum; and an evaluation step of evaluating the lubricity of the surface of the polymeric material based on the intensity of a peak in the Raman spectrum that is attributable to molecular vibrations derived from the silicone.

[2] The quality control method for a polymer material described in [1] above, in which the evaluation step evaluates the slipperiness of the surface of the polymer material based on at least one of the intensity of a first peak in the Raman spectrum that is attributed to the Si-O stretching vibration of the silicone and the intensity of a second peak in the Raman spectrum that is attributed to the C-Si-C stretching vibration of the silicone.

[3] The quality control method for a polymer material described in [2] above, wherein the polymer material is polyethylene, and in the evaluation step, the slipperiness of the surface of the polymer material is evaluated based on at least one of the ratio of the intensity of the first peak to the intensity of the third peak assigned to the _CH2 rolling vibration of the polyethylene in the Raman spectrum and the ratio of the intensity of the second peak to the intensity of the third peak.

[4] The quality control method for a polymeric material according to the above [3], wherein the first peak is a peak having a maximum intensity in the range of 460 cm ^-1 or more and 520 cm ^-1 or less in the Raman spectrum, the second peak is a peak having a maximum intensity in the range of 700 cm ^-1 or more and 720 cm ^-1 or less in the Raman spectrum, and the third peak is a peak having a maximum intensity in the range of 1150 cm ^-1 or more and 1200 cm ^-1 or less in the Raman spectrum.

[5] The quality control method for a polymeric material described in [3] or [4] above, in which in the evaluation step, the slipperiness of the surface of the polymeric material is evaluated based on at least one of the results of whether the ratio of the peak height of the first peak to the peak height of the third peak is 0.043 or more and whether the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more.

[6] The quality control method for a polymeric material according to any one of [3] to [5] above, in which in the evaluation step, the slipperiness of the surface of the polymeric material is evaluated based on at least one of the results of whether the ratio of the peak height of the second peak to the peak height of the third peak is 0.014 or more and whether the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more.

[7] A quality control method for a cable (1) or tube having an insulation (11) made of a polymeric material containing silicone as a lubricant, the quality control method for the cable (1) or tube evaluating the lubricity of the surface of the insulation (11) by the quality control method for polymeric material described in any one of [1] to [6] above.

[8] A method for producing a resin composition, comprising forming a resin composition using a polymeric material containing silicone as a lubricant, the surface slipperiness of which has been evaluated by the quality control method for polymeric materials described in any one of [1] to [6] above.

[9] A polymeric material made of polyethylene containing silicone as a lubricant, which satisfies at least one of the following conditions: a first condition that the ratio of the peak height of a first peak attributed to Si-O stretching vibration of the silicone to the peak height of a third peak attributed to _CH2 rolling vibration of the polyethylene in a Raman spectrum obtained by irradiating a laser is 0.043 or more; a second condition that the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more; a third condition that the ratio of the peak height of a second peak attributed to C-Si-C stretching vibration of the silicone to the peak height of the third peak is 0.014 or more; and a fourth condition that the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more.

[10] A cable (1) or tube equipped with an insulator (11) made of the polymer material described in [9] above.

[11] Factory automation or a factory automation robot equipped with the cable (1) or tube described in [10] above.

Although the embodiments and examples of the present invention have been described above, the present invention is not limited to the above embodiments and examples, and various modifications are possible within the scope of the gist of the invention. Furthermore, the embodiments and examples described above do not limit the invention related to the claims. It should also be noted that not all of the combinations of features described in the embodiments and examples are necessarily essential to the means for solving the problems of the invention.

REFERENCE SIGNS LIST 1 cable 10 conductor 11 insulator 12 pressure winding tape 13 braided shield 14 sheath

Claims (6)

a measuring step of irradiating a polymer material made of polyethylene containing silicone as a lubricant with a laser and measuring a Raman spectrum;
an evaluation step of evaluating the slipperiness of the surface of the polymer material based on the intensity of a first peak attributable to the Si-O stretching vibration of the silicone and the intensity of a third peak attributable to the CH2 rolling vibration _of the polyethylene in the Raman spectrum;
Including,
In the evaluation step, the slipperiness of the surface of the polymer material is evaluated based on at least one of the results of whether or not a ratio of the peak height of the first peak to the peak height of the third peak is 0.043 or more and whether or not a ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.1 or more.
Quality control methods for polymeric materials. the first peak is a peak having a maximum intensity in the range of 460 cm ⁻¹ or more and 520 cm ⁻¹ or less in the Raman spectrum ,
The third peak is a peak having a maximum intensity in the range of 1150 cm ⁻¹ or more and 1200 cm ⁻¹ or less in the Raman spectrum.
The method for quality control of a polymeric material according to claim 1 . a measuring step of irradiating a polymer material made of polyethylene containing silicone as a lubricant with a laser and measuring a Raman spectrum;
an evaluation step of evaluating the slipperiness of the surface of the polymer material based on the intensity of a second peak attributable to the C-Si-C stretching vibration of the silicone and the intensity of a third peak attributable to the CH2 rolling vibration of the polyethylene in the Raman spectrum _;
Including,
In the evaluation step, the slipperiness of the surface of the polymer material is evaluated based on at least one of the results of whether or not a ratio of the peak height of the second peak to the peak height of the third peak is 0.014 or more and whether or not a ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.011 or more.
Quality control methods for polymeric materials. The second peak is at 700 cm in the Raman spectrum. ^-1 Over 720cm ^-1 The peak with the maximum intensity is within the following range:
The third peak is at 1150 cm in the Raman spectrum. ^-1 Over 1200cm ^-1 The peak with the maximum intensity is within the following range:
The method for quality control of a polymeric material according to claim 3. A quality control method for a cable or tube having an insulation made of a polymeric material consisting of polyethylene containing silicone as a lubricant, comprising the steps of:
The method for quality control of a polymer material according to any one of claims 1 to 4 , wherein the slipperiness of the surface of the insulator is evaluated.
A method for quality control of cables or tubes. A method for producing a resin composition comprising: evaluating the slipperiness of a surface by the method for quality control of a polymer material according to any one of claims 1 to 4 ; and forming a resin composition using a polymer material made of polyethylene containing silicone as a lubricant.
A method for producing a resin composition.

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