JPH0517147Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a photoreaction device that generates a polymer through a photoreaction such as photopolymerization.

(Prior Art) Conventionally, this type of photoreaction device consists of a container containing a polymerization mixture consisting of, for example, vinyl monomers, additives, etc., and a plurality of ultraviolet lamps immersed in the polymerization mixture in the container. , and a stirrer installed in the center of the container to stir the polymerization mixture. Then, while stirring the polymerization mixture using a stirrer, the polymerization mixture is irradiated with light from a lamp to cause photopolymerization, thereby producing a uniform polymer.

This production of polymer by photopolymerization progresses from the vicinity of the outer periphery of the lamp, where the amount of light is large, accompanied by an increase in viscosity.

(Problems to be solved by the invention) However, in the conventional apparatus, the low-viscosity polymer mixture at the initial stage of photopolymerization is uniformly stirred by the stirrer, but as the photopolymerization progresses,
Since the viscosity increases to about 100,000 cP, only the vicinity of the stirring blade is stirred.

Therefore, as polymers are produced by photopolymerization, only the area near the stirrer is stirred, and the polymerization mixture near the lamp periphery is not stirred. As a result, photopolymerization progresses locally near the lamp periphery, resulting in a large molecular weight and high viscosity. There was a problem in that a polymer was produced and adhered to the outer surface of the lamp, and a polymer with non-uniform molecular weight was produced throughout.

Therefore, it may be possible to agitate the entire container by increasing the size of the stirring blade or by adding an additional stirrer, but this has the drawbacks of increased equipment cost and poor stirring efficiency.

The present invention was devised in view of such problems, and an object of the present invention is to provide a photoreaction device capable of producing a uniform polymer.

(Means for Solving the Problems) In order to solve the above problems, the present invention immerses a lamp into the reaction mixture in a container and irradiates it with light, and while stirring the reaction mixture, irradiates the reaction mixture with light that causes viscosity increase. In a photoreaction device that performs a reaction to produce a polymer,
A plurality of stirring blades for stirring the reaction mixture near the outer periphery of the lamp are arranged radially from the outer periphery of the lamp at a predetermined gap, and are provided so as to be able to rotate around the lamp.

(Example) Next, an example of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a photoreaction apparatus for photopolymerizing vinyl monomers, which roughly consists of a container 1, a lamp 2, a stirring blade 3, and a driving device 4 for the same.

The container 1 is made of stainless steel and opens upward.
Alternatively, the container body 5 is made up of an enameled container body 5, a lid 6 that covers the container body 5, and a jacket 7 provided on the outside of the container body 5. A support plate 8, which will be described later, is interposed between the container body 5 and the lid 6, and a seal gasket 9 is attached to each flange portion, and they are clamped and fixed together with a clamp 10. The jacket 7 is provided with a cooling water inlet 11 on the lower side and a cooling water outlet 12 on the upper side to allow cooling water to flow between the jacket 7 and the container body 5 to suppress heat generation due to photopolymerization heat. It's getting old. Note that if the amount of heat generated is below the allowable limit due to a small amount of treatment or a slow photopolymerization rate, it is not necessary to flow cooling water through the jacket 7, or the jacket 7 may be removed. good.

The lamp 2 is an ultraviolet lamp equipped with a water-cooled tube 13. The lamp 2 is an ultraviolet lamp equipped with a water-cooled tube 13, and is attached to a bush 14 made of tetrafluoroethylene (hereinafter referred to as the trade name Teflon) fixed to the center of the lid 6 from the outside. They are fitted and inserted into the container body 5. Here, the fitting portions of the inner surface of the bush 14 and the outer surface of the lamp 2 are tapered so that they are pressed together when they are fitted. Note that the lamp 2 does not necessarily include the water-cooled pipe 13.
It does not have to be the one with the attached one, and it can be selected according to the calorific value.

The stirring shaft 15 is in the shape of a tray with a flange made of Teflon, has a hole 16 at the bottom through which the lamp 2 passes, and has an annular reduction gear 17 fixed to the flange. The stirring shaft 15 is loosely fitted onto the outer surface of the bush 14, and is fitted into a fitting hole 18 provided in the center of the support plate 8, and is supported by a bearing 19 formed on the outer periphery of the fitting hole 18. It is supported and is rotatable coaxially with the axis of the lamp 2.

The stirring blades 3 are six strip plates made of stainless steel, and one end of each of the stirring blades 3 is radially attached to the stirring shaft 15 with mounting fittings 20 so as to be equally spaced in the circumferential direction. The other end hangs down to the lower end of the lamp 2 and is supported via a mounting bracket 22 by a Teflon annular support member 21 that fits into the lamp 2 . Here, the stirring blade 3 is located near the lamp 2, and a gap of approximately 2 mm to 30 mm is provided, although this varies depending on the size of the device. If the produced polymer has a high viscosity, the stirring power may be reduced by tilting the stirring blades 3 with respect to the direction of movement, or in the case of a large device, the stirring blades 3 may be placed at symmetrical positions among the six stirring blades 3. Considerations have been made, such as providing two stirring blades 3 near the inner wall of the container body 5 so that stirring is evenly performed not only in the vicinity of the lamp 2 but also over the entire container body 5. You can.

The drive device 4 includes a drive motor 23 , a pinion 25 provided on a transmission shaft 24 of the drive motor 23 , and a reduction gear 17 that meshes with the pinion 25 . The lamp 2 is designed to rotate around the outer periphery of the lamp 2.
26 is a bearing of the transmission shaft 24.

Note that 27, 28, 29, and 30 are screwed to the support plate 8 through the lid 6, and sealed with an O-ring 31, and each have an N ₂ inlet pipe, a polymerization mixture inlet, and a thermometer. It serves as a mounting seat and gas vent.

The photoreaction device having the above configuration is operated in a so-called batch type. That is, the clamp 10 is removed, a polymerization mixture consisting of a vinyl monomer, additives, etc. is poured into the container body 5, and the container is sealed. In the case of a small amount, it can flow in from the input port 28. Then, when the drive motor 23 is driven to rotate the stirring blade 3 and the lamp 2 emits light while stirring the polymerization mixture, photopolymerization progresses from the vicinity of the lamp 2 where the amount of light is large, and a polymer is generated. During this time, the lamp 2 and the container body 5 generate heat, so cooling water may be passed through the water cooling pipe 13 and the jacket 7 of the lamp 2 to cool them, if necessary. The produced polymer is removed by removing the clamp 10. Alternatively, a special outlet may be provided in the container body, and the produced polymer may flow out from the outlet.

Lamp 2 produced by rapid thickening through photopolymerization
The nearby high-viscosity polymer is stirred by the stirring blade 3 and mixed with the low-viscosity polymer near the inner wall of the container body 5. Therefore, the produced polymer near the outer periphery of the lamp 2 does not become extremely viscous and adhere to the lamp 2, and a polymer having a uniform molecular weight is produced throughout the entire container body 5.

That is, according to the photoreaction device according to the present invention,
Lamp 2 where photopolymerization progresses rapidly and the viscosity becomes high
By stirring and mixing near the container body 5, the high viscosity polymer is diffused to the low viscosity side near the inner wall of the container body 5, and local increase in viscosity and high molecular weight of the polymer is suppressed.

Note that the shape of the stirring blade 3 is not limited to that of the embodiment described above, and may be any shape such as a spiral shape. Further, a steady rest may be provided at the lower end of the stirring blade 3. Furthermore, the lower end of the lamp 2 is supported on the container body 5 to support both ends, and then
If this device is made horizontal, the capacity can be increased.

It goes without saying that the photoreaction device according to the present invention can be applied not only to photopolymerization of vinyl monomers as in the embodiments, but also to all photoreactions that involve thickening.

(Effects of the invention) As is clear from the above explanation, according to the invention, since the stirring blades are rotatably provided around the lamp, the highly viscous produced polymer near the lamp is stirred and diffused toward the inner wall of the container. However, since it is mixed with a low-viscosity produced polymer, it has the effect of suppressing local thickening and high molecular weight of the polymer near the lamp, and producing a uniform polymer.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a photoreaction device according to the present invention. 1... Container, 2... Lamp, 3... Stirring blade, 4
... Drive device, 15 ... Stirring shaft body.

Claims (1)

[Scope of utility model registration request] In a photoreaction device, a lamp is immersed in a reaction mixture in a container, irradiated with light, and while the reaction mixture is stirred, a photoreaction accompanied by thickening is performed to produce a polymer. A photoreaction device characterized in that a plurality of stirring blades for stirring are arranged radially at a predetermined gap from the outer periphery of a lamp, and are provided so as to be able to rotate around the lamp.