JP2011069682A - Method and apparatus for observing state change in crystalline resin - Google Patents

Abstract

The present invention provides an observation method and an observation apparatus for a state change of a crystalline resin, which can easily and easily observe a state change in which a crystalline resin in a molten state is crystallized and solidified.
A monitoring method of the state change of the crystalline resin of the present invention, a laser light was irradiated L ₁ in the crystalline resin that state change to the solidified state from the molten state, the laser light passing through the crystalline resin create an image based on the L _2, to observe a state change of the crystalline resin by the image.
[Selection] Figure 1

Description

  The present invention relates to a crystalline resin state change observation method and an observation apparatus for observing a state change in which a crystalline resin in a molten state is crystallized and solidified.

General-purpose plastics such as polyethylene (hereinafter referred to as “PE”), polypropylene (hereinafter referred to as “PP”), polystyrene (hereinafter referred to as “PS”), and polyvinyl chloride (hereinafter referred to as “PVC”) are inexpensive and easy. Therefore, it is widely used as a material for various daily necessities such as bags, various packages, various containers, sheets, etc., industrial parts such as automobiles and electricity, daily necessities, and miscellaneous goods.
On the other hand, general-purpose plastics have drawbacks such as insufficient mechanical strength and low heat resistance, and are therefore often not suitable for machine products such as automobiles and electrical / electronic / information products.
In contrast, engineering plastics such as polyethylene terephthalate (hereinafter referred to as “PET”), polycarbonate (hereinafter referred to as “PC”), polyamide, and polyoxymethylene are excellent in mechanical strength and heat resistance.
However, engineering plastics are expensive and have a disadvantage that they have a large environmental load because they emit a large amount of carbon dioxide in the life cycle assessment and are difficult or impossible to recycle monomers.
Therefore, it is required to improve the mechanical properties and heat resistance of general-purpose plastics. As a method for improving the mechanical properties and heat resistance of general-purpose plastics, it has been proposed to use a crystal having a significantly increased crystal ratio (crystallinity) in PP or PE (Patent Document 1).

International Publication WO2008 / 108251 Specification

The inventors adjusted the molten crystalline resin sheet to a temperature not lower than the crystallization temperature and not higher than the melting point, and rolled and cooled with a pair of rolls at a position where the molten state changed from the molten state to the crystallized state, thereby causing a large elongation strain. As a result, it was found that a highly crystalline crystal can be formed.
However, since there has been no known method for observing a change in the crystalline resin state from the molten state to the crystallized state, it is necessary to accurately grasp the position (solid-liquid interface) where the crystalline state changes from the molten state. Was difficult. For this reason, data on the degree of crystallinity of the obtained crystal and the generation conditions at that time are accumulated, and the position where the crystal changes from the molten state to the crystallized state is estimated, which is inefficient and lacks accuracy. It was. For this reason, it has been difficult to put the method for forming the above highly crystalline crystal into practical use.
Accordingly, an object of the present invention is to provide an observation method and an observation apparatus for a state change of a crystalline resin, which can easily and easily observe a state change in which a molten crystalline resin is crystallized and solidified.

In conventional common sense, when laser light is emitted between a pair of rolls, reflection occurs on the surface of the roll, and it has been thought that accurate information cannot be obtained even when light passing between the rolls is observed.
However, as a result of investigations by the present inventors, a laser beam that has passed through the state change portion of the crystalline resin is received by the imaging unit, an image is formed, and the image is observed, so that the molten crystalline resin is obtained. It has been found that the change in the state of crystallizing and solidifying can be easily observed.

That is, the present invention includes the following configurations.
[1] A laser beam is incident on a crystalline resin that is changing from a molten state to a solidified state, an image is created based on the laser beam that has passed through the crystalline resin, and the state change of the crystalline resin is performed based on the image. A method for observing a change in the state of a crystalline resin, characterized in that
[2] The state change of the crystalline resin generated between the rolling rolls when the molten crystalline resin sheet is rolled with a pair of rolling rolls is observed according to [1] Observation method of state change of crystalline resin.
[3] An apparatus for observing a change in state of a crystalline resin for observing a change in state in which the crystalline resin in a molten state is crystallized and solidified.
A laser light generating unit that emits laser light from a laser light emitting unit toward a portion where the state of the crystalline resin is changing, and an imaging unit that receives the laser light that has passed through the portion where the state of the crystalline resin is changing An apparatus for observing a change in the state of a crystalline resin, comprising:
[4] It is attached to a forming apparatus including a pair of rolling rolls for rolling a crystalline resin sheet in a molten state so as to observe the crystalline resin between the pair of rolling rolls. ] The observation apparatus of the state change of crystalline resin as described in above.

  According to the observation method and the observation apparatus for the state change of the crystalline resin of the present invention, it is possible to easily and simply observe the state change in which the crystalline resin in the molten state is crystallized and solidified.

It is a figure which shows typically the side surface of one embodiment of the observation apparatus of this invention. It is a figure which shows the state change part in the observation apparatus shown in FIG. 1, Comprising: It is sectional drawing at the time of cut | disconnecting a rolling roll horizontally. It is a figure which shows typically an example of the image obtained by imaging the data acquired with the imaging unit.

One embodiment of an observation apparatus (hereinafter abbreviated as an observation apparatus) for the state change of the crystalline resin of the present invention will be described.
FIG. 1 shows an observation apparatus according to this embodiment. The observation apparatus 1 according to the present embodiment is attached to a forming apparatus including a pair of rolling rolls 60 and 60 for rolling the molten crystalline resin sheet S, and the molten crystalline resin sheet S is rolled into the rolling rolls 60 and 60. This is an observation device for observing a state change in which a crystalline resin in a molten state is crystallized and solidified between the rolling rolls 60 and 60 when rolled and cooled by.
This observation apparatus 1 emits a laser beam L ₁ toward a portion A of the crystalline resin between the rolling rolls 60 where the state is changing (hereinafter referred to as “state changing portion A”, see FIG. 2). a laser beam generating unit 10, an imaging unit 20 for imaging by receiving the laser beam L ₂ having passed through the state change part a, a computer 40 for processing imaging data obtained by the imaging unit 20, an image of a computer 40 And an image display unit 50 for displaying the processing result. In the present embodiment, the laser beams L ₁ and L ₂ travel straight from the laser beam generation unit 10 to the imaging unit 20.

Further, in the observation apparatus 1 of the present embodiment, a polarizing plate 31 for adjusting the intensity of the laser light L ₁ emitted from the laser light generation unit 10 is provided between the laser light generation unit 10 and the state change portion A. Is provided.
Between the state change unit A and the imaging unit 20, the focus adjustment lens 32 that adjusts the focus of the laser light L ₂ that has passed through the state change unit A, and the intensity of the laser light L ₂ that has passed through the focus adjustment lens 32. A polarizing plate 33 for adjusting the above is provided.
By adjusting the intensities of the laser beams L ₁ and L _{2 with} the polarizing plates 31 and 33 and adjusting the focus of the laser beam L ₂ with the focus adjustment lens 32, the observation accuracy can be improved.

Laser beam generating unit 10 in this embodiment includes a laser light generator 11, and a laser beam emitting unit 12 for emitting the laser light L ₁ generated by the laser light generator 11. As the laser beam generator 11, a helium-neon laser, a semiconductor laser, a YAG laser, a carbon dioxide laser, or an excimer laser can be applied. Since the laser beam has high straightness and can pass through a narrow place, it is suitable for the present invention for observing a narrow portion.
Imaging unit 20 is disposed in front of the emission direction of the laser beam L ₁ emitted from the laser beam emitting unit 12, the laser beam L ₂ having passed through the focusing lens 32 and the polarizing plate 33, built-in image sensor ( (Not shown). As the imaging unit 20, for example, a CCD camera, a CMOS camera, or the like is appropriately selected and used according to the wavelength of the laser beam.
As the image display unit 50, a liquid crystal display device, a CRT, or the like is used.

An observation method using the observation apparatus 1 will be described.
In the observation method of this embodiment, first, laser light is generated by the laser light generation unit 11 of the laser light generation unit 10.
The laser beam L ₁ is emitted from the laser beam emitting unit 12 so as to be parallel to the rotation axis of the pair of rolling rolls 60 and 60 and pass between the rolling rolls 60 and 60.
Then, to adjust the intensity of the laser beam L ₁ through a laser beam L ₁ to the polarizer 31, the laser beam L ₁ having an adjusted intensity to be incident on the state change part A between the rolling rolls 60, 60.
In state change part A, part of the molten crystalline resin sheet S between the rolling rolls 60, 60 is transmitted through the laser light L _1, part of the crystalline state (solidification state) to scatter the laser light L _1. Therefore, the light amount of the laser beam L ₂ having passed through the state change part A increases at a portion of the molten state, less the portion of the crystalline state.

Next, the laser light L ₂ that has passed through the state change portion A is passed through the focus adjustment lens 32 and the polarizing plate 33 and then received by the imaging unit 20. Then, the data acquired by the imaging unit 20 is imaged by the computer 40, and the processing result is displayed by the image display unit 50 and observed.

Examples of the crystalline resin constituting the crystalline resin sheet S to which the above observation method can be applied include polyalkylene, polyamide, polyether, and liquid crystal polymer. Specifically, polyolefins such as polyethylene, isotactic polypropylene, syndiotactic polypropylene, and poly-4-methylpentene, or crystalline ethylene / propylene copolymers, polyamides such as nylon 6, nylon 66, and nylon 12, and polybutylene. Polyesters such as terephthalate and polyethylene terephthalate, syndiotactic polystyrene, polyphenylene sulfide, polyether ether ketone, wholly aromatic polyester, polytetrafluoroethylene, polyvinylidene fluoride, and other fluorine resins, polyethylene succinate, polybutylene succinate, etc. Aliphatic polyester, polylactic acid, polyvinyl alcohol, polyacetal, polyether nitrile and the like. However, it is not limited to these resins.
These crystalline polymers may be used alone, or may be used in combination with the same type and different molecular weights, or may be used in combination with an amorphous polymer.
When isotactic polypropylene is used, the stereoregularity by mmmm is preferably 95% or more, and more preferably 97% or more, in that higher rigidity can be obtained.
It is preferable that the crystalline resin sheet S is melted while being adjusted to a crystallization temperature or higher and a melting point or lower.

In the observation method using the observation apparatus 1, the light amount of the laser beam L ₂ having passed through the portion of the molten lot, because the light amount of the laser beam L ₂ having passed through the part of the crystalline state is small, in the obtained image The melted portion becomes bright and the crystalline portion becomes dark. Therefore, it is possible to easily and simply observe the state change of the crystalline resin from the obtained image, and it is possible to grasp the position and situation of the state change. Further, according to this method, it is possible to observe a change in the state of the crystalline resin even at a very small portion between the rolling rolls 60 and 60.

FIG. 3 schematically shows an example of an image obtained by imaging the data acquired by the imaging unit 20. This example shows a state change part when a molten polypropylene sheet is supplied downward and rolled between rolling rolls 60 and 60 (roll rotation speed 90 m / min, roll temperature 140 ° C.) with a roll interval of 200 μm. This is an example in which A is observed.
The rolled polypropylene sheet supplied to the rolling rolls 60, 60 changes from a molten state to a crystallized state during rolling. The portion where the status change has occurred in the image observed by the observation apparatus 1, as shown in FIG. 3, have become less as the amount of the laser beam L ₂ having passed through the polypropylene sheet is directed from top to bottom in FIG. Eventually, the laser beam is not transmitted at all. Since the boundary between the part that transmits the laser beam and the part that does not transmit is the solid-liquid interface, the position where the molten state changes to the crystallized state can be easily and easily grasped by observing this image. .

Note that the present invention is not limited to the above embodiment. For example, in the present invention, the polarizing plates 31 and 33 and the focus adjustment lens 32 may not be provided.
Moreover, the state change part may not be between the rolling rolls 60 and 60, and should just be a part and its periphery which change to a crystalline state from a molten state at the time of shape | molding crystalline resin.
The traveling directions of the laser beams L ₁ and L ₂ may be bent using a reflecting mirror.

DESCRIPTION OF SYMBOLS 1 Observation apparatus 10 Laser light generation unit 11 Laser light generation part 12 Laser light emission part 20 Imaging unit 31, 33 Polarizing plate 32 Focus adjustment lens 40 Computer 50 Image display unit 60 Roll A State change part S Crystalline resin sheet

Claims (4)

  A laser beam is incident on the crystalline resin that is changing from a molten state to a solidified state, an image is created based on the laser beam that has passed through the crystalline resin, and a change in the state of the crystalline resin is observed using the image. A method for observing a change in the state of a crystalline resin.   2. The crystalline resin according to claim 1, wherein a state change of the crystalline resin occurring between the rolling rolls is observed when the molten crystalline resin sheet is rolled with a pair of rolling rolls. Method for observing state changes. An apparatus for observing a state change of a crystalline resin that observes a state change in which a crystalline resin in a molten state is crystallized and solidified.
A laser light generating unit that emits laser light from a laser light emitting unit toward a portion where the state of the crystalline resin is changing, and an imaging unit that receives the laser light that has passed through the portion where the state of the crystalline resin is changing An apparatus for observing a change in the state of a crystalline resin, comprising:   4. The apparatus according to claim 3, wherein the apparatus is attached to a forming apparatus including a pair of rolling rolls for rolling the crystalline resin sheet in a molten state so as to observe the crystalline resin between the pair of rolling rolls. An observation device for the state change of crystalline resin.

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