KR810001399B1 - Process for the continuous casting of liquid polymerizable compositions - Google Patents

Abstract

A copolymer syrup from Me methacrylate(I) and acrylate esters contg. bis(4-tertbutylcyclohexyl)peroxydicarbonate(II) is continuously charged to a space between 2 endless belts and 2 tubular gaskets, passed through heating areas at<100oC and 100oC and cooled to give a continious transparent sheet. Thus, a syrup from 3:97 mixt. of Et acrylate and I contg. 0.001 % azobisisobutyronitrile and 20 % copolymer(III) was mixed with 0.3% II, degassed and charged to an app. described above, heated 11.4 min at 80oC and 4.9 min at 120oC to give a 30-mm sheet of III contg. 0.43% risidual monomer.

Description

Continuous polymerization method of polymerizable liquid composition

1 is a graph showing the relationship between the amount of the dialkylperoxy dicarbonate (expressed in molar parts per 100 parts by weight of syrup) and the temperature of the hydrothermal synthesis zone in the scope of the present invention;

2 to 4 are graphs showing the relationship between the preferred amount of dialkylperoxy dicarbonate (expressed in molar parts per 100 parts by weight of syrup) and the temperature of the hydrothermal polymerization zone under certain conditions.

5 shows (1) and (2) moving belts, (3) (4) (5) and (6) pulleys, (7) supports, (8) rollers, and (A) to (D) Are hydrothermal polymerization zones, (D) to (E) are heat treatment zones, and (E) to (F) are longitudinal side views of a continuous polymerization apparatus for carrying out the present invention as cooling zones.

The present invention provides a polymerizable composition, which is a fluid obtained by dissolving a dialkylperoxy dicarbonate as a polymerization initiator in a syrup of methyl methacrylate, into a space between two moving belts to continuously polymerize the composition to form a plate-shaped methacryl. It relates to a continuous polymerization method for producing a resin polymer.

The cell casting method using a pair of tempered glass plates to polymerize methyl methacrylate to produce excellent methacrylic resin polymers such as transparency, gloss and weather resistance is known as a general method. However, this method is a container assembly injection, container disassembly and batch type, which is therefore almost manually performed to increase the manpower and manufacturing cost.

Therefore, the continuous casting method is developed in a way that can be substituted for the cell casting method by studying the rationalization of the present invention, and is now usefully implemented in the industry.

Continuous casting methods are disclosed, for example, in US Patents 2500728 and 3872197, UK Patents 1168083, and Canadian Patents 824582. This method supplies (1) a polymerizable composition of methyl methacrylate and a polymerization initiator to the space between two moving belts positioned up and down, and (2) methacrylic acid as hot water in the process of moving the belt. It is a step of polymerizing (main polymerizing) methyl, heat-treating with hot air or far-infrared heater to complete the polymerization, and (3) removing the produced tubular polymer from the other end of the belt.

However, since this method requires a large amount of equipment for increasing the manufacturing cost of the methacryl resin plate, a high-efficiency polymerization procedure to be completed in a short time has been desired.

In order to efficiently produce a desired methacryl resin plate having a high commercial value by the continuous polymerization method, it is required to satisfy the following five requirements.

(1) When the thickness of the plate polymer produced is 3mm or less, the main polymerization time should be within 20 minutes, suitably within 15 minutes, and the heat treatment time should be within 10 minutes.

(2) Bubbles should not be formed in the plate polymer during main polymerization or heat treatment. That is, no bubbles should be present in the prepared plate-like polymer.

(3) The content of residual monomer in the prepared plate polymer should be 1.5% by weight or less.

In other words, the heat deformation temperature of the plate polymer should be high.

(4) The plate polymer should be able to be melt adhesive and at the same time excellent in solvent resistance.

(5) Bubbles should not form when the prepared plate polymer is heated at 180 ° C for 30 minutes.

That is, no heating bubbles should be generated.

As for (1), since the polymerization equipment of this method requires a large investment, the high production capacity is a condition that the continuous polymerization method requires.

Regarding (2), the presence of bubbles in the plate-shaped polymer significantly lowers the merchandise value, so it is necessary to select suitable polymerization conditions in which bubbles are not generated during the main polymerization or heat treatment.

Regarding (3), when the amount of the residual monomer exceeds 1.5% by weight, the heat deformation temperature is lowered and the creep characteristics are poor, which is not preferable.

Therefore, in order to lower the content, it is necessary to properly select the conditions for heat treatment and main polymerization.

Regarding (4), the plate-shaped methacryl polymer is to be adhered by a solvent, such as dichloromethane, in its adhesion processing.

At the same time, the polymer value should be excellent in solvent resistance because its commodity value is damaged by the generation of heat generated by the solvent.

As for (5), the plate-shaped methacryl polymer is usually heated and processed by the bending process or the vacuum forming method, so that if the temperature at which the polymer starts to foam when heated is low, bubbles are generated during heating and the product value of the polymer is lowered.

Therefore, the plate polymer should not bubble when heated at 180 ° C. for 30 minutes.

In order to simultaneously and accurately carry out polymerization conditions that simultaneously satisfy the five requirements described above, the inventors of the present invention use a polymerization initiator, for example, 2,2'-azobis (2), which is substantially used in a continuous polymerization method under various polymerization conditions. , 4-dimethylvaletonitrile) (hereinafter referred to as "ADVN") and lauroyl peroxide (hereinafter referred to as "LPO"), for example, plate-shaped methylacryl having a thickness of 3 mm or less As a result of the polymerization, it was found that the requirements (2) (3) (4) and (5) were simultaneously met by extending the main polymerization time to 30 to 40 minutes.

However, when the thickness of the plate polymers using ADVN or LPO is, for example, 3 mm or less, in order to shorten the condition of (1), that is, the main polymerization time to within 20 minutes and suitably within 15 minutes. The following problems are eliminated.

Increasing the amount of ADVN or LPO resulted in the presence of bubbles due to polymerization in the prepared plate polymer, or heating bubbles at a temperature of 180 ° C. or lower to obtain a desired plate polymer having satisfactory quality.

In addition, instead of increasing the amount of ADVN or LPO used, the temperature due to the hydrothermal polymerization zone is increased in the same manner as described above. I could not get it.

As described above, it was found that in the continuous polymerization method, five requirements were not simultaneously satisfied using a conventional polymerization initiator. Therefore, even if the thickness of the plate polymer is, for example, 3 mm or less, the total polymerization time required for the main polymerization and the heat treatment is Japanese Patent Publication No. As is well known in 16713/1973, 16993/1973 and 16994/1973, it did not shorten within 30 to 60 minutes.

It is an object of the present invention to provide a continuous polymerization method that can satisfy the above five requirements simultaneously.

Another object of the present invention is to provide a continuous casting method for producing a plate-like polymer having a low cost and excellent quality.

Another object of the present invention is to provide a polymerizable liquid composition obtained by dissolving dialkylperoxy dicarbonate as a polymerization initiator in a syrup of methyl methacrylate having a polymer content of 15 to 35% by weight between two moving belts. It is to provide a continuous casting method of injecting into the space and then polymerizing the composition to produce a plate-shaped methacryl polymer with high performance.

Other objects and advantages will be apparent from the description below.

According to the invention R is an alkyl or alkoxy alkyl group having from 4 to 10 carbon atoms

Expression:

Of a polymerizable liquid composition obtained by dissolving a polymerization initiator (hereinafter referred to as &quot; initiator A &quot;) in a syrup of methyl methacrylate having a polymer content of 15 to 35% by weight between the two up and down moving belts and these belts. Continuously fed into a space surrounded by successive cascades of the two belts, the two belts moving in the same direction at the same speed, these gaskets being provided on each side of the belt at least one in close contact with both belts Then, these belts are driven through the hydrothermal polymerization zone to polymerize the composite, and the amount of the initiator A (expressed in the water quantity relative to 100 parts by weight of the syrup) is related to the temperature (° C) of this zone. 5 points marked at 1 degree:

^{Ⅰ (2 × 10 -5, 90} ), Ⅱ (1.5 × 10 -3, 90), Ⅲ (1.5 × 10 -3, 60), Ⅳ (1.8 × 10 -4, 60) and Ⅴ (2 × 10 ^{- 5,} completing the polymerization hayeoseo drives the belt through a heat treatment zone to include in the surrounding area by a straight line passing through each point of 85) and then formed in a continuous polymerization process, characterized in that that contains a plate-like polymer in the other end of the belt will be.

In addition, according to the present invention, the main polymerization time is shortened as follows according to the thickness of the plate polymer.

That is, the thickness of 3 mm or less is less than 20 minutes, the thing of 3 mm or more and 4 mm is 25 minutes, and the thing of 4 mm or more and 6 mm is 30 minutes or less.

In addition, the residual monomer can also be 1.5% by weight or less in a short time for heat treatment. The syrup of methyl methacrylate which is the main component in the present invention has a content of polymer of 15 to 35% by weight, suitably 20 to 30% by weight.

As a suitable thing of the viscosity of this syrup, 5 poise or more is good at 25 degreeC.

When the content of the polymer in the syrup is 15% by weight or less, the yield of the plate polymer is lowered.

For example, when the thickness of the plate is 3 mm or less, it is difficult to produce a plate-shaped methacryl polymer having good desired quality within 20 minutes of the main polymerization time.

Because of this, it is impossible to further reduce the main polymerization time to 15 minutes or less.

In addition, when the polymer content is more than 35% by weight, the viscosity of the syrup becomes high, making it difficult to supply the syrup to the space between the two moving belts, which is not preferable.

The viscosity of the syrup is preferably 5 poise or more at 25 ° C.

Syrups having a viscosity of less than 5 poise have a tendency to generate bubbles due to the polymerization when the main polymerization time is shortened, and also to lower the quality of the produced plate-like polymer, especially the temperature at which foaming starts due to heating.

On the other hand, since the syrup with high viscosity becomes difficult to supply to space, the upper limit of a viscosity is normally up to 100 poise.

That is, a suitable syrup is 15 to 35 weight% of polymerization rates, and it is good to use the thing of the viscosity of 5-100 poise at 25 degreeC.

When the syrup used in the present invention contains a monomer copolymerizable with methyl methacrylate other than methyl methacrylate which is the main component in the syrup, the content of the monomer is 30% by weight or more relative to the total weight of the syrup Should not exceed

Other monomers include C ₂ -C ₈ methacrylic acid alkyl esters, styrene, halogens and alkyl derivatives thereof, vinyl acetate, acrylonitrile and their derivatives, and C ₁ -C ₈ acrylic acid alkyl esters.

Among them, alkyl esters of acrylic acid are suitable for increasing the temperature at which heat foaming starts when the main polymerization time is shortened.

Suitable examples of the alkyl acrylate ester of C ₁ -C ₈ include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, secondary-butyl acrylate, tert-butyl acrylate, Hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, and octyl acrylate.

Of these, methyl acrylate and ethyl acrylate are particularly suitable. The amount of the alkyl acrylate ester is effectively used in the range of 0.5 to 15% by weight based on the total weight of the syrup.

Moreover, it unexpectedly discovered that content of the residual monomer of a plate-shaped polymer can be made into 1.5 weight% or less by the heat treatment of surprisingly short time by containing alkyl acrylate.

In addition, in the present invention, as long as the amount within the range that can achieve the object of the present invention, various additives such as heat stabilizers, ultraviolet absorbers, colorants, plasticizers, mold release agents and fillers may be selected and contained in the syrup as necessary.

In order to manufacture the syrup of 15-35 weight% of polymers of methyl methacrylate used for this invention, it carries out by the following process.

(1) Methyl methacrylate or methyl methacrylate and a mixture of the above-mentioned monomers copolymerizable with methyl methacrylate and a mixture containing the above-mentioned additives and fillers are partially polymerized to achieve the required polymerization rate and composition.

(2) Methyl methacrylate or the mixture described above is partially polymerized, and then monomers, additives and fillers copolymerizable with methyl methacrylate described above are added to form a polymerization rate and composition required.

(3) The monomers described above are obtained by polymerizing the mixture described above and dissolving the resulting polymer in methyl methacrylate or a methyl methacrylate containing additive and filler which can be copolymerized with methyl methacrylate or a mixture of methyl methacrylate. The polymerization rate and composition are achieved.

Suitable examples of initiator A used in the present invention include di-n-butylperoxy dicarbonate, diisobutyl peroxydicarbonate, di-tert-butyl peroxy dicarbonate, dicyclohexyl peroxy dicarbonate, di 2-ethylhexyl peroxy dicarbonate, di-ethoxyethyl peroxy dicarbonate, di-3methoxybutyl peroxy dicarbonate and bis (4-tert-butyl cyclohexyl) peroxy dicarbonate, which are solely Or these can be used in combination with 2 or more types of these.

Of these, di-tert-butyl peroxy dicarbonate and bis (4-tert-butyl cyclohexyl) peroxy dicarbonate are suitable.

Also, in view of ease of handling and safety workability, the plasticizers and diluents which are difficult to react with the initiator A are used together with the initiator A in a weight of 10 times or less with respect to the initiator A. For example, dibutyl phthalate, dioctyl phthalate, dioctyl phthalate, and the like are included.

Diluents include, for example, mineral oil, toluene and the like. The appropriate range of the amount of the initiator used and the temperature of the hydrothermal polymerization zone are the relationship between the amount used (expressed in molar parts per 100 parts by weight of the syrup) and the temperature (° C.) in five points in Fig. 1: I (2 × 10 ^{−). 5,} through the 90), ⅱ (1.5 × 10 -3, 90), ⅲ (1.5 × 10 -3, 60), ⅳ (1.8 × 10 -4, 60) and ^{ⅴ (2 × 10 -5, 85} ) It should be decided appropriately to be done simultaneously in the enclosed area.

In this way, the above five conditions are met simultaneously to obtain a target plate-like polymer.

In general, if the final plate polymer has a relatively large thickness, foaming by polymerization is more likely to occur due to the heat of polymerization, so that a suitable region within the range of the use-temperature in FIG. 1 is to reduce the amount and at the same time lower the temperature. That is, when the thickness of a polymer is small, it means that superposition | polymerization which reduces generation | occurrence | production of a bubble by polymerization heat and a high polymerization rate is performed. In this way, suitable polymerization conditions are changed in the region of FIG. 1 according to the thickness of the plate-like polymer as follows.

(1) When the thickness is 3 mm or less, a suitable condition is the relationship between the amount of starting agent A (expressed in molar parts per 100 parts by weight of the syrup) and the temperature of the hot water polymerization zone. × 10 ^-5 , 90), II (1.5 × 10 ^-3 , 90), III (1.5 × 10 ^-3 , 65), IV (2.5 × 10 ^-4 , 65), and V (3 × 10 ^-5 , 85 This is done simultaneously in the enclosed area by a straight line passing through five points.

(2) When the thickness is 3 mm or more and 4 mm or less, the relationship between the amount of the initiator A, which indicates the appropriate conditions in mole copies, and the temperature is 5 points in Fig. 3: I (3 × 10 ⁻⁵ , 90), Surrounded by straight lines passing through II (1.5 × 10 ^-3 , 85), III (1.5 × 10 ^-3 , 60), IV (2.5 × 10 ^-4 , 60) and V (3 × 10 ^-5 , 85) To be done simultaneously in the domain.

(3) When the thickness is 4 mm or more and 6 mm or less, the relationship between the temperature and the amount of the initiator A, which is expressed in terms of moles, is five points in Fig. 4: I (2 × 10 ^-5,90 ), II Area enclosed in a straight line through (1.5 × 10 ^-3 , 80), III (1.5 × 10 ^-3 , 60), IV (1.8 × 10 ^-4 , 60) and V (2 × 10 ^-5 , 85) It's done at the same time.

In Figs. 1 to 4, the straight line I-II shows an upper limit of the temperature intersecting with the above-mentioned amount of the initiator A, but in the higher region, bubbles due to polymerization are generated in the plate-like polymer.

The straight line II-III has shown the upper limit of the usage-amount of the initiator A with respect to heat foaming, when the plate-shaped polymer is heated at 180 degreeC for 30 minutes.

The straight lines III-IV, IV-V and V-I show the lower limit of the temperature intersecting with the usage amount of the initiator A, but in the lower region, the tubular polymer of interest is not obtained within the predetermined main polymerization time.

The enclosed regions of the lines I-II, II-III, III-IV, IV-V and V-I of Figs. 1 to 4 form an enclosed region showing the relationship between the amount of use and the temperature, but the polymerization state is If it is under the conditions of the range, the polymerizable liquid composition of the present invention may be polymerized to easily obtain a plate-like polymer.

In FIG. 1 thru | or FIG. 4, the quantity of the initiator A is shown by the logarithmic scale. In addition, the main polymerization of the polymerizable liquid composition was carried out in a state where the relationship between the amount of the initiator A and the hydrothermal polymerization zone temperature was simultaneously shown in the region of FIG. 1, and then the residual heat in the plate-like polymer when the heat treatment was performed at 110 to 115 ° C. The content of the monomer is reduced to 1.5% or less by weight in a very short time, thereby obtaining a desired plate-like polymer having high heat deformation temperature and excellent solvent resistance.

Other polymerization with initiator A in order to reduce the content of residual monomer in an amount within a range in which foaming does not lower below 180 ° C and foaming does not occur when the temperature at which the polymerization initiators other than initiator A are finally started is foamed. You may select and use an initiator together.

The amount of other initiator used with initiator A is usually 2 × 10 ⁻⁴ parts or less as water relative to 100 parts by weight of the syrup.

In general, free base initiators may be used as a combination initiator, but among them, lauroyl peroxide and tertiary are used in order to further reduce the content of residual monomers and to prevent the formation of polymerization foam without lowering the temperature at which it starts to heat foam. Butyl peroxy pivalate is advantageously used.

The production apparatus used in the present invention is generally known as a double-belt Kenvey, and the tubular polymer of interest is obtained by operating this apparatus as follows.

Space between the moving belts by rotating two moving belts in the upper and lower position relations at the same speed and the same speed, and moving at least one continuous gasket on both sides of the moving belts in contact with both moving belts. After sealing, the polymerizable liquid composition is continuously supplied into the space, and the polymerizable liquid composition is continuously fed through the hydrothermal polymerization zone and the heat treatment zone where the composition is polymerized, and the plate-like polymer is continuously produced from the other end between the moving belts.

This apparatus has the following mechanism.

The first is a mechanism for maintaining a close contact between the belt and the gasket, and at the same time adjusting the distance between the belts to the required thickness of the plate polymer to maintain this distance. It is a device of an apparatus that violently conforms to the change of melt resulting from polymerization of a composition.

In addition, as the material of the moving belt, metal rotating bands such as steel or stainless steel rotating bands are preferable. These metal bands can also be used by coating it with a plastic film. If this plastic film has a shape-side surface, the surface of the manufactured plate-like polymer will be taken in this shape. When using a metal band, the thickness of the band is preferably 0.1 to 3 mm, preferably 0.5 to 2 mm.

The polymerizable liquid composition is heated together with the moving belt to heat from the outside of the moving belt to polymerize the polymerizable liquid composition, but the heating zone is divided into a hydrothermal polymerization zone and a heat treatment zone. In the hydrothermal polymerization zone, the hot water is showered on the outside of the moving belt or heated by moving the moving belt during hot water heating. The hot water temperature may be constant throughout the hydrothermal polymerization zone, or may be changed stepwise or continuously. Also good.

The polymerizable liquid composition of the present invention polymerizes the hydrothermal polymerization zone while traveling with the above-mentioned moving belt, and is usually polymerized at 80 to 90% by weight, with the remainder being polymerized in the hydrothermal treatment zone. Therefore, since most of the polymerization reactions take place in the hydrothermal polymerization zone, polymerization in this zone is generally referred to as main polymerization.

The above-mentioned polymerizable liquid composition drives the heat treatment zone along with the above-described moving belt after the hydrothermal polymerization zone, in which hot air is emitted to the outside of the moving belt or heated by a far-infrared heater.

The heat treatment temperature may be constant throughout the heat treatment zone, or may be performed stepwise or continuously.

The above-mentioned polymerizable liquid composition of the present invention is sufficiently completed until exiting the heat treatment zone.

In this way, the above-mentioned polymerizable liquid composition is supplied to the space between the moving belts and is sufficiently polymerized while traveling through the hydrothermal polymerization zone and the heat treatment zone together with the moving belts, and the plate-like polymer at the other end between the moving belts. It is preferable to cool the sample by lifting it and installing a cooling zone after the heat treatment zone to lift the plate polymer. It is preferable to cool so that the temperature of the plate-shaped polymer at the time of lifting is 100 degrees C or less, suitably 90 degrees C or less, As a cooling method, the method of spraying cold water or cold air to the outside of the above-mentioned moving belt by a shower or exposing it to cold air. Or ice-cooling at room temperature.

An example of the manufacturing apparatus used for this invention is demonstrated in detail according to drawing.

In FIG. 5, the pair of pulleys (3) and (4) and the pair of pulleys (5) and (6) apply tension to the moving belts (1) and (2), respectively, and pulleys (4) and (6). ) Is driven at the same circumferential speed to drive the moving belts 1 and 2, and the polymerizable liquid composition and the cask are continuously drawn from the openings between the pulleys 3 and 5 provided at one end. The plate-like polymer is lifted from the opening between the pulleys 4 and 6 provided at the other end.

In FIG. 5, the lower axle shift belt is longer than the axle shift belt, and the position of the hydrothermal polymerization zone, heat treatment zone and cooling zone installed between point A (starting point of main polymerization) and point F (end point of cooling zone). Indicates.

That is, the area between points (A) and (D) is a hydrothermal polymerization zone, the area between points (D) and (E) is a heat treatment zone, and the area between points (E) and (F) is Cooling zone. The moving belts 1 and 2 travel through these zones in the order described above.

And the moving belts (1) and (2) run from the point (A) to the point (B) inclined in a straight line at a position where the point (A) is higher than the point (B) with respect to the horizontal, and at the point (B) Up to C), the vehicle travels in a curved shape, and the moving belt indicates that the position of the point F runs from the point C to the point F in a straight line higher than the position of the point C. .

A non-rotating support 7 having a frame structure from point A to point B supports the up and down moving belt and also maintains the distance from the shanghai east belt at the required length. From point B to point F, these two belts are supported as a group of rollers 8 so that they can be easily adjusted to the volume change of the polymerizable liquid composition.

Although an example of the manufacturing apparatus used in the present invention has been described in detail, this manufacturing apparatus is not limited to this, and it is of course used by those known as manufacturing apparatus for the continuous casting method.

For example, the running pattern of two upper and lower belts between the inlet port (which feeds into the space between the moving belts of the polymerized liquid composition) and the outlet port (removing the produced plate polymer) can be horizontal or inclined in a straight line. Or it may be natural curving. In addition, a device for maintaining a predetermined amount of the above-described composition may be installed in the inlet.

As a cast used in the present invention, a plastic string is generally used. As the plastic, flexible plastics such as soft polyvinyl chloride, polyethylene, polypropylene, ethylene acetate-vinyl copolymer, ethylene-propylene rubber, natural rubber and other rubbers are used. Among them, polyvinyl chloride is particularly useful, in which soft polyvinyl chloride is usually used and containing 100 parts by weight of polyvinyl chloride and 0 to 170 parts by weight of a plastic material (for example, dioctylphthalate) is useful. do. The shape of the gas gasket may be square, rectangular or circular in cross section, but in general, a gas gasket such as a hollow pipe is suitable.

The invention is illustrated by the following examples, which are not intended to limit the invention.

In the examples,% is% by weight unless otherwise specified. The test in the Example was performed as follows.

The heat deflection temperature was measured in accordance with JIS K 6718, and the foaming due to polymerization determined the presence or absence of bubbles by visual observation of the obtained tubular polymer. Foaming by heating was carried out by heating the obtained plate-like polymer in a circulating hot stove for 30 minutes at 180 ° C. and then visually determining the presence of bubbles.

The reduced viscosity was measured by a 0.1% chloroform solution of the polymer at 25 ° C. and the residual monomer was measured by gas-liquid chromatography by dissolving the plate polymer in methylene chloride.

Example 1

The polymerization is carried out using the continuous polymerization apparatus shown in FIG. This device has the following structure.

The horizontal distance between point A (hydrothermal polymerization start point) and point B is 2,900 mm, using a movable belt of stainless steel upper and lower polished with a mirror width of 500 mm and a thickness of 0.6 mm, and a passage between these two points. Is inclined in a straight line at an angle of 3 ° to the horizontal, both belts are supported by the non-rotating support of the frame structure, and the horizontal distance between the points B and C is 2240 mm, and the passage between these two points is It is curved in a concave shape with a radius of curvature of 25,423 mm, and both belts are supported by rollers from point (B) to point (C).

The horizontal distance between point (C) and point (F) is 4860 mm, the passage between these two points is inclined in a straight line at an angle of 2.1 ° with respect to the horizontal, and both belts are at point (C). It is supported by rollers.

The horizontal distance between point (A) and point (F) is divided into three zones of 10,000 mm.

The first zone (AD, 6240 mm) is a hydrothermal polymerization zone for heating with hot water at 85 ° C. for heating, the second zone (DE, 2670 mm) is a heat treatment zone for heating with hot air at 120 ° C. for heating, and The third zone (EF, 1090 mm) is a cooling zone with cold wind for cooling.

A pipe-like soft polyvinyl chloride containing a polymerizable liquid composition and 55% of dioctylphthalate is continuously supplied to the space between both belts at the inlet on the point (A) to prepare the composition as follows.

0.001% of azobisisobutyronitrile was added to methyl methacrylate containing 3% ethyl acrylate and polymerized at 80 ° C. 0.3% bis in 20% of the syrup of polymer with a viscosity of 13 poise at 25 ° C. (4-tert-Butylcyclohexyl) peroxy carbonate (this syrup is dissolved in (containing 0.75 × 10 ⁻³ mole parts of the above-mentioned peroxy dicarbonate) based on 100 parts by weight of the syrup, and the resulting syrup Is degassed under reduced pressure.

Initial tensions of 5 kg / mm 2 and 4 kg / mm 2 are applied to the upper and lower belts, respectively, and these belts are driven at a speed of 545 mm / min. The distance between the two belts in the zone A-B is adjusted so that the plate polymer produced has a thickness of 3 mm. The syrup is polymerized by passing through the hydrothermal polymerization zone and the heat treatment zone, cooled in the cooling zone and drawn off at the other end of the belt. This product obtains a product of polymethyl methacrylate without plate-shaped transparent polymeric foam having a thickness of about 3 mm. At this time, the polymerization time in the hydrothermal polymerization zone and the heat treatment zone was very short and took 11.4 minutes and 4.9 minutes, respectively. The obtained product has the following properties.

The reduced viscosity of 1.35 dl / g, the residual monomer of 0.43% and the heat distortion temperature were 102 ° C. The foaming due to heating was not seen. There was no change in the surface even when the obtained product was exposed to ethyl acetate vapor for 1 hour.

Example 2

Polymerization of the syrup was prepared as follows using the apparatus used in Example 1. To methyl methacrylate containing 3% ethyl acrylate, 0.001% of azobisisobutyronitrile was added and polymerized at 80 ° C, and 0.45% in a syrup of 15% with a viscosity of 7 poise at 25 ° C. Of bis (4-tert-butylcyclohexyl) peroxy carbonate (this test contains 1.13 × 10 ⁻³ mole parts of the above-mentioned peroxy dicarbonate based on 100 wt.% Of syrup) and the resulting syrup Degassing under reduced pressure.

At this time, the temperature of the heat treatment zone is maintained at 120 ° C., but the temperature and speed of the hydrothermal polymerization zone and the moving speed of the belt in Example 1 are shown in Table 1 as follows.

TABLE 1

The resulting product had a plate-like transparent polymethyl methacrylate having a thickness of about 3 mm and in which foaming did not occur during polymerization despite a short polymerization time. In addition, these products do not cause foaming due to heating.

Example 3

The polymerization of the syrup was prepared by supplying a syrup to the apparatus of Example 1, wherein the temperature of the hydrothermal polymerization zone and the heat treatment zone were 85 ° C and 125 ° C, respectively.

0.001% of azobisisobutyronitrile was added to butyl acrylate containing a suitable 2-ethylhexyl acrylate and polymerized at 80 ° C. to obtain a syrup having a polymerization rate of 25% at a viscosity of 20 poise at 25 ° C. Dissolve 0.3% of bis (4-tert-butyl cyclohexyl) peroxydicarbonate in a syrup (the syrup contains 0.75 × 10 ⁻³ of peroxydicarbonate in molar parts per 100 parts by weight of the syrup) Then, the resulting syrup is depressurized.

The results are shown in Table 2 below.

TABLE 2

The obtained product of the plate-like transparent polymethylacrylate having a thickness of about 3 mm was not able to see the polymerization foam and the heating foam even after the polymerization for a short time.

Example 4

Preparation of syrup 4-1:

Methyl methacrylate containing 3% ethyl acrylate is added to a polymerization reactor equipped with a reflux condenser, nitrogen-introducing tube, thermometer and stirrer. The reactor was replaced with a nitrogen gas atmosphere, and then the monomer was heated to 90 DEG C while stirring, and 0.08% of 2,2'-azobis (2,4-dimethylvaleronitrile) was added thereto. The temperature rise by the heat of polymerization is soon known.

The reaction mixture is kept at 100 to 102 캜 under reflux for 10 minutes and then cooled. The syrup thus obtained has a viscosity of 20 poises and a polymerization rate of 25% at 25 ° C.

Preparation of Syrup 4-2:

Methyl methacrylate is added to the polymerization reactor, and 0.1% of 2,2'-azobis (2,4-dimethylvaleronitrile) is added thereto. The mixture is polymerized under reflux to obtain a syrup having a viscosity of 40 poise and a polymerization rate of 30% at 25 ° C.

Preparation of syrup 4-3:

Methyl methacrylate containing 5% ethyl acrylate was added to the polymerization reactor, and 0.1% 2,2'-azobis (2,4-dimethylvaleronitrile) was added thereto at 90 占 폚. The mixture was refluxed to polymerize to obtain a syrup having a viscosity of 40 poise and a polymerization rate of 30% at 25 ° C. It is dissolved in each syrup obtained for an appropriate amount of bis (4-tert-butyl cyclohexyl) peroxy dicarbonate and then degassed under reduced pressure.

The degassed syrup was fed to the apparatus used in Example 1 to carry out polymerization, but the temperatures of the hydrothermal polymerization zone and the heat treatment zone were changed from those in Example 1, and the results are shown in Table 3. The product obtained has a thickness of about 3 mm and a plate-like transparent polymethyl methacrylate having no foaming during the polymerization despite the short polymerization time. They also had no air bubbles due to heating.

TABLE 3

Example 5

Methyl methacrylate was added to the polymerization reactor used in Example 4, and 0.08% of 2,2'-arbis (2,4-dimethylvaleronitrile) was added at 90 ° C and the mixture was polymerized under reflux to give 25 A syrup is obtained with a viscosity of 20 poises and a polymerization rate of 25% at &lt; RTI ID = 0.0 &gt;

Dissolve 0.03% of lauroyl peroxide and 0.15% of bis (4-tert-butyl cyclohexyl) peroxy dicarbonate in this syrup (the resulting syrup is 0.38x10 ^-3 moles per 100 parts by weight of syrup). Negative peroxy dicarbonate, followed by degassing under reduced pressure.

The degassed syrup was fed to the apparatus used in Example 1, and polymerization was carried out by driving a moving belt at a rate of 529 mm / min while maintaining the hydrothermal polymerization zone and the heat treatment zone at 90 ° C and 120 ° C, respectively. The time required for polymerization in the former and latter zones is very short, reaching 11.8 and 5.0 minutes, respectively.

The resulting product has a thickness of about 3 mm to give a tubular transparent polymethyl methacrylate product without foaming. The product had a reduced viscosity of 1.75 dl / g, a residual monomer of 1.10%, and no foaming due to heating. The heat deformation temperature was 101 ° C.

Example 6

25% of methacrylic resin (sumitox Chemical Co., Ltd. product name (sumipex-B MH)) is dissolved in methyl methacrylate to obtain a syrup having a viscosity of 10 poise at 25 DEG C. An appropriate amount of ethyl acrylate is then obtained. Or methyl acrylate is added, and then bis (4-tert-butyl cyclohexyl) peroxydicarbonate is dissolved in the resulting syrup in the amounts shown in Table 4 (expressed in molar parts relative to 100 parts by weight of syrup). Then, it is degassed under reduced pressure.

This degassed syrup was fed to the apparatus used in Example 1, and the hydrothermal polymerization zone and the heat treatment zone were maintained at 85 ° C and 125 ° C, respectively, and the polymerization was carried out by driving the moving belt at various speeds shown in Table 4. The results are shown in Table 4. The time required for polymerization in the zones before and after and the latter is very short as shown in Table 4.

The obtained product has a thickness of about 3 mm and a product of methyl transparent pulley methacrylate, which does not foam during polymerization despite a short polymerization time. There was also no foaming due to heating.

TABLE 4

Example 7

In the syrup obtained in Example 4 (Syrup No. 4-2), 0.06% of lauroyl peroxide and 0.1% of bis (4-tert-butyl cyclohexyl) peroxy dicarbonate (the resultant syrup is the weight of the syrup Per 100 parts of water, containing 0.25 × 10 ⁻³ of peroxy dicarbonate) is dissolved, followed by degassing under reduced pressure. The degassed syrup is fed to the apparatus used in Example 1, and polymerization is carried out by driving a moving belt at a rate of 543 mm / min while the hydrothermal polymerization zone and the heat treatment zone are maintained at 90 ° C and 120 ° C, respectively.

In the former and latter zones, the polymerization time is very short, reaching 11.5 and 4.9 minutes, respectively. The resulting product obtains a plate-like transparent polymethyl methacrylate having a thickness of about 3 mm and containing no bubbles. This product has the following properties.

A reduced viscosity of 2.05 dl / g, a content of 0.86% of residual monomer and no foaming due to heating, were at a heat deflection temperature of 103 ° C.

Example 8

Methyl methacrylate containing 5% ethyl acrylate was added to the polymerization reactor used in Example 4, and 0.08% of 2,2'-azobis (2,4-dimethylvaleronitrile) was added thereto at 90 占 폚. do. The mixture is polymerized under reflux to obtain a syrup having a viscosity of 20 poises and a polymer content of 25% at 25 ° C.

0.3% bis (4-tert-butyl cyclohexyl) peroxy dicarbonate in this syrup (the resulting syrup contains 0.75 × 10 ⁻³ mole parts peroxy dicarbonate by weight of syrup) Is dissolved and degassed under reduced pressure. The degassed syrup is fed to the apparatus used in Example 1, and the polymerization is carried out by driving the moving belt at various speeds while maintaining the hydrothermal polymerization zone and the heat treatment zone at 85 ° C and 125 ° C, respectively. The results are shown in Table 5.

TABLE 5

The resulting product obtained a product of plate-like transparent polymethyl methacrylate having a thickness of about 3 mm and containing no bubbles. It was also clear from Table 5 that there was no foaming due to heating and no problem in quality even if the polymerization time was shortened.

Example 9

25% of methacrylic resin (registered trademark sumipex-B MH of Sumitomo Chemical Co., Ltd.) is dissolved in methyl methacrylate, and then 3% ethyl acrylate is added to this to obtain a syrup. An appropriate amount of bis (4-tert-butylcyclohexyl) peroxy dicarbonate is dissolved in this syrup and subsequently degassed under reduced pressure. The degassed syrup is fed to the apparatus used in Example 1 and the distance between the belts in the zones A-B is adjusted to produce a plate-like polymer with a thickness of 4 mm.

The polymerization is carried out by driving the moving belt at various speeds and by changing the temperature of the hydrothermal polymerization zone and the heat treatment zone. The results are shown in Table 6. The resulting product has a thickness of about 4 mm and becomes a sheet-like transparent polymethyl methacrylate that does not foam during polymerization with a short polymerization time, even if it is thick. There was also no foaming due to heating.

TABLE 6

Example 10

An appropriate amount of bis (4-tert-butyl cyclohexyl) peroxy dicarbonate is dissolved in the syrup obtained in Example 8 and then degassed under reduced pressure. The degassed syrup is fed to the apparatus used in Example 1 and then the distance between the belts in zones A-B is adjusted to produce a plate polymer having a thickness of 5 mm.

The belt is driven at various speeds to effect polymerization at varying temperatures in the hydrothermal polymerization zone. The results are shown in Table 7. The resulting product has a thickness of about 5 mm and obtains a flat, transparent methyl methyl methacrylate free of foaming during the polymerization even if thick. There was also no foaming due to heating.

TABLE 7

Example 11

To a syrup obtained in Example 5 was a 50% dibutyl phthalate solution of 0.12% di-tert-butyl peroxy dicarbonate (this syrup produced was 0.26 × 10 ⁻³ mole parts peroxy to 100 parts by weight of the syrup Containing dicarbonate), followed by degassing under reduced pressure. The degassed syrup is fed to the apparatus used in Example 1, and polymerization is carried out by driving a moving belt at a rate of 378 mm / min while maintaining the hydrothermal polymerization zone and the heat treatment zone at 85 ° C and 120 ° C, respectively.

In the former and latter zones the polymerization times are 16.5 minutes and 7.1 minutes, respectively. The resulting product has a thickness of about 3 mm and a plate-shaped transparent polymethyl methacrylate free of bubbles. This product has the following properties. It had a reduced viscosity of 2.39 dl / g, a residual monomer content of 1.22 and a heat deflection temperature of 102 ° C. without foaming due to heating, and the product did not show any change even when exposed to the vapor of ethyl acetate for 1 hour.

Example 12

Examples 5 to the syrup obtained in a 0.03% peroxide-tau work di-secondary dissolved in 50% dibutyl phthalate solution of 0.14% of butyl di-carbonate, FER oxy (per 100 parts by weight of the syrup 0.30 × 10 ^-3a Molar part of peroxy dicarbonate), followed by degassing under reduced pressure. The degassed syrup is fed to the apparatus used in Example 1, where the distance between the moving belts is adjusted to produce a plate-like polymer with a thickness of 5 mm.

The polymerization is carried out by driving the moving belt at a rate of 297 mm / min, during which the hydrothermal polymerization zone and the heat treatment zone are maintained at 75 ° C. and 130 ° C., respectively. The resulting product has a plate-like transparent polymethyl methacrylate having a thickness of about 5 mm and containing no bubbles. This product has the following properties.

The reduced viscosity of 1.79 dl / g, the content of the residual monomer of 0.60%, and no foaming due to heating, and the heat distortion temperature of 103 ° C were 103 ° C.

Example 13

In a syrup obtained in Example 5, 0.18% of a 50% dibutyl phthalate solution of di-secondary-butyl peroxy dicarbonate was dissolved (0.38 × 10 ⁻³ mol parts peroxy dicarbonate based on 100 parts by weight of the syrup). And degassing under reduced pressure.

The degassed syrup was fed to the apparatus used in Example 1 and the distance between the moving belts was adjusted to produce a plate-like polymer having a thickness of 5 mm in which the hydrothermal polymerization zone and the heat treatment zone were 70 ° C. and 120 ° C., respectively. The polymerization is carried out by driving the moving belt at a speed of 271 mm / min while maintaining the temperature of 271 mm / min. The product obtained obtains a plate-like transparent polymethyl methacrylate having a thickness of about 5 mm and containing no bubbles. This product has the following properties.

The reduced viscosity of 1.61 dl / g, the residual monomer content of 0.55% and no foaming due to heating, and the heat deformation temperature were 103 ° C.

Example 14

In a syrup obtained in Example 4 (syrup No. 4-2), 0.14% of a 50% toluene solution of diisobutyl peroxy dicarbonate was dissolved (0.30 × 10 ⁻³ mole parts Per Oxy dicarbonate), followed by degassing under reduced pressure. The degassed syrup is supplied to the apparatus used in Example 1, and polymerization is carried out by driving the moving belt at a rate of 520 mm / min while the hot water polymerization zone and the heat treatment zone are maintained at 85 ° C and 130 ° C, respectively.

In the former and latter zones the polymerization times were 12 and 5.13 minutes, respectively. The obtained product has a plate-like transparent polymethyl methacrylate having a thickness of about 3 mm and containing no bubbles. This product has the following properties.

The residual monomer content of 1.06%, no foaming due to heating, the heat distortion temperature was 101 ° C, and no change was observed on the surface when the product was exposed to ethyl acetate vapor for 1 hour.

Example 15

In a syrup obtained in Example 4 (Syrup No. 4-3), a 50% dioctyl phthalate solution of 0.52% di-2-ethylhexyl peroxy dicarbonate was dissolved (0.75x10 for 100 parts by weight of syrup). ^-3 mol parts of peroxy dicarbonate), followed by degassing under reduced pressure. The degassed syrup is supplied to the apparatus used in Example 1, and polymerization is carried out by driving a moving belt at a rate of 780 mm / min while maintaining the hydrothermal polymerization zone and the heat treatment zone at 85 ° C and 130 ° C, respectively.

The polymerization times in the former and latter zones are 8 minutes and 3.42 minutes, respectively. The obtained product has a plate-like transparent methacrylic acid polymethyl methacrylate having a thickness of about 3 mm and containing no bubbles. This product has the following properties.

It has a reduced viscosity of 1.50 dl / g, a residual monomer content of 0.66%, no foaming due to heating, a heat deflection temperature of 95 ° C., and no change on the surface when the product was exposed to ethyl acetate vapor for 1 hour.

Example 16

27.5% of methacryl resin (registered trademark Sumiqex-BVMH of Sumitomo Chemical Co., Ltd.) is dissolved in methyl methacrylate. Then, a suitable amount of a 50% toluene solution of di-iso-butyl peroxy dicarbonate is dissolved therein and then degassed under reduced pressure.

The degassed syrup is supplied to the apparatus used in Example 1, and the polymerization is carried out by changing the temperature of the hydrothermal polymerization zone and the heat treatment zone by driving the belt moving speed. The results are shown in Table 8. The obtained product obtained a plate-like transparent polymethyl methacrylate having a thickness of about 3 mm and containing no bubbles. In addition, air bubbles were not generated due to heating.

TABLE 8

Reference Example 1

An appropriate amount of lauroyl peroxide is dissolved in the syrup obtained in Example 8 and subsequently degassed under reduced pressure. The degassed syrup is supplied to the apparatus used in Example 1, and polymerization is carried out by variously driving the moving speed of the belt while maintaining the hydrothermal polymerization zone and the heat treatment zone at 80 ° C and 120 ° C, respectively. A plate polymer having a thickness of about 3 mm shown in Table 9 was obtained.

As apparent from Table 9, when the polymerization was carried out in a short time using lauroyl peroxide as the initiator, the shorter the polymerization time, the more polymerized foaming occurred, and any foaming due to heating was also observed.

TABLE 9

Reference Example 2

A suitable amount of 2,2'-azobis (2-4-dimethylvaleronitrile) is dissolved in the syrup obtained in Example 4 (Syrup No. 4-1), and then degassed under reduced pressure. The degassed syrup is supplied to the apparatus used in Example 1, and the hydrothermal polymerization zone and the heat treatment zone are maintained at 80 ° C and 120 ° C, respectively, to effect polymerization by varying the speed of movement of the belt. A plate-like polymer having a thickness of about 3 mm shown in Table 10 is obtained.

As apparent from Table 10, when the polymerization was carried out in a short time using 2,2'-azobis (2,4-dimethylvaleronitrile) as an initiator, the shorter the polymerization time, the more polymerized foam appeared and Foaming was also seen in either case.

TABLE 10

Reference Example 3

25% of methacrylic resin (registered trademark Sumiqex-B MH of Sumitomo Chemical Co., Ltd.) is dissolved in methyl methacrylate, and 3% of methyl acrylate is added thereto to obtain a syrup. Bis (4-tert-butylcyclohexyl) peroxy dicarbonate is dissolved in this syrup, and then degassed under reduced pressure. The degassed syrup is supplied to the apparatus used in Example 1, and polymerization is carried out at various temperatures in the hydrothermal polymerization zone and the heat treatment zone. A plate-like polymer having a thickness of about 3 mm shown in Table 11 is obtained.

As apparent from Table 11, when the amount of the initiator was larger than the range of the present invention, the polymerization time was shortened by that amount, but no polymerization foam was produced, but foaming due to heating appeared.

On the other hand, even if the amount of the initiator is within an appropriate range, polymerization foaming occurs, and at the same time, when the temperature of the hydrothermal polymerization zone exceeds the range of the present invention, the polymerization becomes incomplete, and the content of the residual monomer is greatly increased, which is undesirable. Can not do it.

TABLE 11

Reference Example 4

25% of methacryl resin (registered trademark Sumiqex-B MH of Sumitomo Chemical Co., Ltd.) is dissolved in methyl methacrylate to obtain a syrup. Then, bis (4-tert-butyl cyclohexyl) peroxydicarbonate is dissolved in this syrup, followed by degassing under reduced pressure. The degassed syrup is supplied to the apparatus used in Example 1, and polymerization is carried out by varying the temperature of the hydrothermal polymerization zone, and the polymerization is carried out by controlling the belt movement speed so as not to cause polymerization foaming. The results are shown in Table 12.

As for the obtained product, neither the plate-shaped polymethyl methacrylate product of about 3 mm thickness could see foaming by superposition | polymerization foam or heating. However, as apparent from Table 12, when the amount of the initiator is less than the range of the present invention, even if the amount of the initiator is within a suitable range, the polymerization time is long, which results in a disadvantage of lowering productivity.

TABLE 12

Reference Example 5

A mixture of methyl methacrylate and 0.001% azobisisobutyronitrile was polymerized at 80 ° C and 50% of di-tert-butyl peroxy dicarbonate was added to a syrup of 8.4% of the polymer at a viscosity of 2 poise at 25 ° C. 0.23% of a% dibutyl phthalate solution is dissolved (comprising 0.49 × 10 ⁻³ moles of peroxy dicarbonate based on 100 parts by weight of the syrup), followed by degassing under reduced pressure. The degassed syrup was supplied to the apparatus used in Example 1, and polymerization was carried out by driving the moving speed of the belt at a speed of 312 mm / minute while maintaining the hydrothermal polymerization zone and the heat treatment zone at 85 ° C and 130 ° C, respectively.

In this polymerization, the polymerization time of the former and latter zones was very long, requiring 20 minutes and 8.6 minutes, respectively, but the polymerization of the hydrothermal polymerization zone proceeded inadequately, resulting in foaming in the heat treatment zone. I could not get it.

Reference Example 6

In a syrup obtained in Example 5, 0.94% of a 50% dibutyl phthalate solution of di-tert-butyl peroxy dicarbonate was dissolved (containing 2.01 × 10 ⁻³ mol parts peroxy dicarbonate based on 100 parts by weight of the syrup). Then, deaeration is carried out under reduced pressure. The degassed syrup was supplied to the apparatus used in Example 1, and polymerization was carried out by driving the speed of the moving belt at 780 mm / min while maintaining the hot water polymerization zone and the heat treatment zone at 85 ° C and 130 ° C, respectively.

In the former and latter zones the polymerization time took minutes, 8 minutes and 3.4 minutes. The obtained product obtained plate-shaped polymethyl methacrylate having a thickness of about 3 mm, but had the following properties. That is, the reduced viscosity of 0.66 dl / g, the residual monomer content of 1.17%, and the heat deformation temperature were 103 ° C. The product contained no foam by polymerization, but foamed by heating.

Reference Example 7

Dissolve 0.47 of 50% dibutyl phthalate of di-tert-butyl peroxy dicarbonate in the syrup obtained in Example 5 (containing 100 × 10 ⁻³ mole parts per 100 parts by weight of syrup), and then continue to depressurize Degassing under The degassed syrup is fed to the apparatus used in Example 1, and the polymerization is carried out by driving the moving belt at a rate of 312 mm / min while maintaining the hydrothermal polymerization zone and the heat treatment zone at 55 ° C and 130 ° C, respectively.

In the former and latter zones, the polymerization time took 20 minutes and 8.6 minutes, respectively, but the polymerization did not proceed sufficiently in the former zone, causing foaming in the latter zone to obtain a satisfactory plate polymer having a thickness of about 3 mm. I could not.

Claims (1)

expression,

A polymerizable liquid composition obtained by dissolving a polymerization initiator represented by the following in a syrup of methyl methacrylate having a polymerization rate of 15 to 35% by weight is carried out at the same speed in two consecutive moving belts in the vertical direction. The vehicle is run in a state in which at least one continuous gas gasket is brought into contact with both moving belts on both sides of the moving belt and continuously supplied to the enclosed space between the moving belts, and the moving belt is driven to pass through the hydrothermal polymerization zone. The relationship between the amount of the initiator (in moles per 100 parts by weight of the syrup and the temperature of the zone) and the temperature of the zone was found in five points in Fig. 1: I (2 × 10 ⁻⁵ , 90) and II (1.5 × 10). ^-3 , 90), Ⅲ (1.5 × 10 ^-3 , 60), IV (1.8 × 10 ^-4 , 60), V (2 × 10 ^-5 , 85) in the area formed by connecting the points in a straight line Drive the belt through the heat treatment zone to complete the polymerization and then Continuous Polymerization of the polymerizable liquid composition which contains water as that in the other end of the belt method (provided wherein R is an alkyl or alkoxyalkyl group having from 4 to 10 carbon atoms).

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