JPH0363536A - Stress sensitive body - Google Patents

Abstract

PURPOSE:To allow the visual decision of a stress by effectively utilizing the color developability, under stretching stress, of polyarylene sulfide (PAS). CONSTITUTION:A fiber, cloth or film consisting of the PAS causes color development at a specific wavelength under the stretching stress. The PAS refers to a polymer having the -R-S-group (where R is phenylene, biphenylene, naphthalene, biphenylene ether or 1 to 6C lower alkyl substd. deriv. thereof) obtd. by bringing a polyhalo-substd. cyclic compd. having an unsaturation group between the adjacent ring atoms and alkaline metal sulfide into reaction in an org. polar rolvent as a repeating unit.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a novel stress sensing body made of polyarylene alphaide (hereinafter abbreviated as PS), and in particular, the present invention relates to a stress sensing body made of polyarylene alphaide (hereinafter abbreviated as PS). It concerns the sensing body.

<Prior Art> Conventionally, as a means for sensing or detecting tensile stress, a method called a strain gauge that converts stress into an electrical signal has been generally used.

However, this method has disadvantages such as limited use because it requires expensive equipment such as complicated electric circuits including amplifiers and the like in order to sense stress and use it for measurement.

<Problems to be Solved by the Invention> The present invention eliminates the need for a complicated and expensive electric circuit such as a strain gauge to sense tensile stress, and provides a stress sensing body that allows humans to visually determine stress. This is what I am trying to do.

Means for Solving the Problems The present inventors have arrived at the present invention by discovering that fibers, fabrics, or films made of PAS develop color at a specific wavelength under tensile stress.

That is, the present invention is a stress sensing body made of a PAS polymer, which changes the reflection intensity of light of a specific wavelength under tensile stress. Examples of the form of PAS include fibers, fabrics, and films.

In the present invention, PAS refers to a monoR-8- group (wherein R: It is a polymer having as a repeating unit phenylene, biphenylene, naphthalene, biphenylene ether or a lower alkyl substituted derivative thereof having 1 to 6 carbon atoms, and is typically described in detail in US Pat. No. 3,354,129. However, anything that can be included in PAS's Zessho is included in the scope of the present invention. In the present invention, polyphenylene sulfide (hereinafter referred to as PPS) in which R is a phenylene group is particularly preferred.

The cause of PAS exhibiting coloration at a specific wavelength under tensile stress is currently under active investigation, but no clear conclusion has been reached.

However, the fact that the reflected intensity of light of a specific wavelength changes can be confirmed by the method described later, and can be easily determined by human visual observation.

Coloring properties associated with changes in elongation stress are easily expressed in the form of fibers, fabrics, films, etc., and can be used in a wide variety of applications such as strings, belts, and tapes.

The color development of PAS under tensile stress is close to blue-green, and in terms of physical detection, a decrease in the reflectance of 630 mμ with a spectrophotometer is observed, which is easily seen with the naked eye.

Next, a method for manufacturing a stress sensor made of PAS of the present invention will be described. According to this method, the stress sensing body described above can be obtained, but the manufacturing method thereof is not limited to the following content.

PAS polymer with an intrinsic viscosity of 0.20 or more from 290 to 31
After melting at 0°C, it is spun and cooled to obtain an undrawn yarn.

The obtained undrawn yarn is drawn either continuously after spinning or after being wound up once. At this time, the 10th drawing roller is heated to a temperature above the glass transition point of PAS, and the 20th drawing roller is stretched 2 to 4 times and taken off, followed by the 20th drawing and 30th drawing. 150 while relaxing 1-10% between the
Heat-treated by contacting with a plate heated to ~200℃
Obtain AS drawn yarn.

In addition, a light stabilizer, an antioxidant, an antistatic agent, a dyeability improver, an adhesion improver, etc. may be added as necessary prior to melt spinning or during the process of manufacturing the stress sensor of the present invention. All of them can be used, except those that have a significant effect on the characteristics of the present invention depending on their formulation.

The PAS fiber thus obtained can be used as it is as a stress sensor. It is also possible to use it by making it into a filament by doubling or twisting it, or by processing it into a woven or knitted fabric. Further, any material obtained by forming short fiber nonwoven fabric or long fiber nonwoven fabric (so-called spunbond) using a known method, or by molding it into a film can also be used as a stress sensor.

Next, a method for measuring or evaluating each numerical value according to the present invention will be described.

(Intrinsic viscosity) PAII degree of 1-chloronaphthalene is 0.5 to 1 g/
Adjust the sample solution by dissolving it so that d f, 2
The solution viscosity is measured using an Oswald viscometer with an ice fall time of 6-7 seconds at a temperature of 0'C.

0.5g/cl and Ig using the same viscometer for measurement
The intrinsic viscosity is determined from the falling time of 20 ml of solution of /df. (Spectral Reflectance) The reflectance of the sample with respect to the standard sample in the visible range of 400 to 760 mμ is measured using a self-recording spectrophotometer (Hitachi EPR-2 type).

As described above, after processing PAS into fibers, fabrics, or films, it is possible to provide a sensor that can easily detect stress by utilizing color development in the visible range under tensile stress.

<Example> Example 1 A PPS chip with an intrinsic viscosity of 0.22 is used as a raw material, and a pore diameter of 0.3
After melt spinning at 300°C from a spinneret with 24 holes, it was wound up, and then stretched to 2.8 times with a 10-layer kept at 95°C and a 20th-layer at room temperature. 30th-
A 5% relaxation heat treatment was performed using a 200° C. hot plate provided between the roller and the roller to obtain a drawn filament of 70 denier×24 filaments. The spectral reflectance when the obtained drawn filament yarn was stretched under various stresses was calculated as
As shown in the figure. Furthermore, the relationship between the reflectance at 630 mμ and the stress is shown in FIG.

As is clear from FIGS. 1 and 2, when the stress sensing body of the present invention is stretched, the reflectance of a specific wavelength decreases.
The stress state of the sensor can be seen with the naked eye.

<Effects of the Invention> According to the present invention, by using a lightweight and inexpensive organic material called PAS, color development is easily observed in response to stretching stress, and it can be an effective means as a stress sensor.

[Brief explanation of drawings]

Figure 1 shows various types (40 kg/d, 50 kg/w
The relationship between the wavelength and spectral reflectance of the filament yarn under the stress of J) is shown. FIG. 2 shows the relationship between the stress of the filament yarn and the reflectance at 630 mμ.

Claims (1)

[Claims] Stress sensing body made of polyarylene sulfide polymer.