JPS5962609A - Manufacture of flame retardant acrylic resin molded article - Google Patents

Abstract

PURPOSE:To obtain the titled molded article in high productivity, without lowering the physical properties, by supplying methyl methacrylate, alpha-methylstyrene, styrene and unsaturated acids together with a flame retardant continuously into the space formed by the gaskets running between a pair of endless belts, and polymerizing the monomer mixture in the space. CONSTITUTION:A pair of endless belts 1, 1' are placed opposite to each other interposing a gap therebetween. A forming space is formed by the opposite faces of the belts 1, 1' and the gaskets 7, 7' running in accordance with the movement of the belts and sandwiched between the belts. A monomer mixture composed of 40-80wt% of methyl methacrylate monomer or its prepolymer, 1-15wt% of alpha-methylstyrene, 5-15wt% of styrene, 5-15wt% of maleic anhydride, and 1- 15% of methacrylic acid, and proper amounts of a halogen-containing flame retardant and a polymerization initiator, is supplied to the front end of the forming space, and polymerized continuously in the space. The polymer plate 12 is taken out of the apparatus from the outlet end.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a flame-retardant acrylic resin molded product having a high degree of flame retardancy and excellent physical properties. Regarding the manufacturing method. More specifically, 9 the present invention provides methacrylic rPl fl, α-
Methylstyrene, styrene.

A flame-retardant acrylic system with excellent physical properties due to continuous casting of a polymerization base consisting of a resin atomized from maleic anhydride and methacrylic acid, a halogen-containing flame retardant, and a polymerization initiator. The present invention relates to a method for producing an IVJ resin molded product.

Acrylic resin is a thermoplastic resin whose main component is methyl methacrylate, and is used as lighting materials and signboards due to its exceptional transparency, excellent weather resistance, good mechanical properties, and surface heat resistance. Although it is widely used as a display material, a building material, an electrical equipment material, etc., it is flammable, so its field of use is limited.

It is already known that flame retardancy can be imparted to acrylic resins by adding certain organic phosphate esters, but these organic phosphate esters generally have a plasticization rate of 7iJ, and the acrylic resin obtained It has the drawbacks that it significantly lowers the heat distortion temperature of the resin molded product and also significantly lowers the mechanical strength of the resin molded product. In addition, the added flame retardant V greatly increases the water absorption of the final composition, so when this flame retardant board is used outdoors, the sheet absorbs water and forms creases. This was often the cause of product complaints.

Moreover, it is required to exhibit the flame retardant effect by minimizing the amount of the flame retardant 7 added.

Although many studies have been conducted in this regard, no satisfactory results have yet been obtained.

The present inventors have carried out intensive testing to improve the above-mentioned drawbacks of conventional flame-retardant acrylic resins, and as a result, we have determined that the base polymer has been changed to the conventional flame-retardant acrylic resin alone9 or methyl methacrylate and methacrylate resin. Methyl methacrylate with a specific composition in place of acrylic resin consisting of acid.

α-Methylstyrene, styrene + 2fi, ':r Consisting of water malein V and methacrylic l crotch (Otsukiji +
M'1'') and a halogen-containing flame retardant are continuously polymerized in the presence of a polymerization initiator, resulting in a molded product with a t lower than that of conventional flame-retardant acrylic resin.
h+v.

The present invention was achieved based on the discovery that flammability can be imparted and that the production method is economically advantageous.

In other words, the gist of the present invention is to provide a gasket that is sandwiched between the opposing surfaces of two endless belts that run opposite each other with a certain gap between them and the gasket that runs following the running of the belts. In the molding space formed by
Methyl Styrene 7]-15J amount, Methyl Styrene 5 to 15 double threshold.

Maleic anhydride 5-15'i Ginchi and methacrylic acid 1
A resin composition consisting of ~15 parts by weight, a halogen-containing flame retardant, and a polymerization raw material are supplied at the same time as the polymerization starts, and are continuously polymerized inside the molded wall, and are formed into a plate shape from the downstream end. The present invention provides a method for producing an acrylic resin molded article with high flammability, characterized by extracting a polymer.

The methacrylic ester component that makes up the molded product of the present invention has the optical properties inherent to sigma-1 fat.

It is a necessary component to maintain weather resistance or mechanical properties, and its amount is used in the resin material in a range of 40 to 88% by weight.If the stitch used is less than 40M, the above special properties will be lost. C1. Moreover, when the amount of nails exceeds 88%, the effect of improving fIj thermal properties and flame retardancy becomes small.

In addition, the α-methylstyrene component constituting the molded product is one of the components that improves the heat resistance and heat resistance of the resulting molded product, and is one of the components that improves the heat resistance and heat resistance of the molded product. It is preferably used in a range of 3 to 1 OM%. 1 layer +71
If it is less than 15% by weight, heat resistance will not be sufficient, and if it exceeds 15% by weight, mechanical properties and productivity will decrease.

In addition, the steel component that makes up the molded product is not a component that directly improves the heat resistance and flame retardance of the molded product, but
Co-TI of α-methylstyrene and maleic anhydride, which are heat resistance-improving ingredients (indirectly improves heat resistance by increasing synthetic skin responsiveness, and at the same time has a significant effect on improving productivity at °C). Moreover, it has extremely favorable effects on improving the mechanical properties, coloration properties, and molding processability of the obtained molded product. The external effects were shown.As styrene stool fragments, 5 to 15% of resin particles were used.
It is necessary to have a caretaker, and if it is less than 5% by weight, productivity will be poor.

If it exceeds 15 vehicles, it will be heat resistant and efficient! There is a tendency for the level of agency to decline.

In addition, the anhydrous maleic component constituting the molded product has the effect of increasing the copolymerization reactivity of α-methylstyrene and the effect of improving the heat resistance of the molded product by interacting with styrene.
The proportion used should range from 5 to 15% by weight of the resin material, preferably from 10 to 15% by weight. If the usage rate is less than 5% by weight, productivity and heat resistance will be poor;
When the amount exceeds 5N, mechanical properties and heat resistance deteriorate.

Furthermore, the methacrylic acid component constituting the molded product has a great effect on improving flame retardancy and heat resistance, and its usage ratio is 1 to 15% by weight of the resin material.

Preferably 3~], OIi amount ratio, more preferably 5~7
This is related to N quantity. If the usage ratio is less than IN#%, the effect of improving flame retardancy '16, J: and heat resistance will be small.

If it exceeds 15% by weight, the haze value of the molded product becomes thicker, and the water absorption rate increases, resulting in adverse effects on physical properties.

The above are the two essential components constituting the molded product of the present invention and their usage ratios, but they also affect productivity, heat resistance, and flame retardance of the final molded product.

Considering the overall balance of resin properties such as mechanical properties, optical properties, and processability, the number of moles of α-methylstyrene is α, and the number of moles of styrene is β.

and where the number of moles of maleic anhydride is r.

m The blending ratio of α-methylstyrene, styrene, and manic anhydride in the fatty material (α + β)/γ is 1.1 to 1
．． It is most desirable to be in a relationship of indulgence equal to 5. When the blending ratio is less than 1.1, mechanical properties, water resistance, and chemical properties tend to be low.
In a range greater than 5, there is a tendency for thermal properties to decrease by 1Iiiit.

In the present invention or depending on the purpose of use, acrylic acid, acrylated methyl, and ethyl (meth)acrylate are used within the scope of the present invention.

Other copolymerizable monomers such as (meth)acrylic butyl, vinyl acetate or divinylbenzene.

Triallyl cyanurate, triallyl in cyanurate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate.

A polyfunctional crosslinking monomer such as trimethylolpropane trimethacrylate is added to the resin material within a range of 200% by weight or less.
More than one species may be further blended and copolymerized.

In the present invention, one part or all of methacrylic acid, which is one component of the copolymerization, may be substituted with one other organic acid, such as acrylic acid or maleic acid, if necessary.

Although it is possible to replace the unsaturated fermented acid with a saturated organic acid such as methacrylic acid, methacrylic acid as used in the present invention has better flammability.

The effect of surface 1 thermal properties is significant.

The flame retardant used in Europe for forming the molded product of the present invention is halogen-containing condensation)! It is a halogen-containing flame retardant such as a monoacid ester or a halogenated polyphosphonate. As the halogen-containing condensed phosphorus ester, chlorinated polybosphate is the best, and even the former of chlorinated polyphosphate is i;
The i'i-containing first generation is 5 to 30 weights 11φ, preferably 10 to
It is desirable that the flame retardancy is 20 to 40 and the chlorine content is 20 to 40.

Examples of chlorinated polyphosphates include CR-505 and CR-509 produced by Daihe Chemical Industry Co., Ltd.
, CR-511 and CR-513, Vylor Schiff produced by Kashima Kogyo Co., Ltd., and APR-THIOI produced by Asahi Glass Co., Ltd., and the like. Among these, CR-509 is effective when used in the present invention. 7.1: Regarding CR-509.

Although its exact structure is unknown, it is a chlorine-containing condensed phosphoric acid ester having a phosphorus-carbon bond, and its chlorine content at λt is 26.0%, and its phosphorus content is 14.0%.

In addition, non-logenated polyphosphonates, chlorinated polyphosphonates, and chlorinated polyphosphonates which are also used in the present invention are preferable, and among them, Phosgard C, which is produced by Monsanto Company in the United States, is also called -22-R and has the following formula: are particularly effective.

The amount of the above-mentioned nitrogen-containing, j11r, and combustion agent used in the present invention cannot be determined unconditionally depending on the degree required for the product, but it is usually 3 to 40% by weight, more preferably 10% by weight based on the resin molding. ~ 30 Jigage Section. If the amount of flame retardant is less than 3 times, it is not sufficient in terms of imparting flame retardant properties, and -1:
If the content exceeds 40% by weight, physical properties tend to deteriorate significantly, such as heat resistance decreasing and water absorption increasing.

The production method of the present invention includes a resin material comprising the above-mentioned methyl methacrylate monomer or a partial polymer thereof, α-methylstyrene, styrene, maleic anhydride 6, and methacrylic acid, the above-mentioned flame retardant, and a required amount of After adding a polymerization initiator to prepare a polymerization raw material, the polymerization raw material is sandwiched between the opposing surfaces of two endless belts that face each other with a certain gap and run at °C while the belts run. The gasket is supplied from the upstream end to the molding space formed by the gasket running following the gasket, and the gaskets are continuously overlapped inside the molding space.

This is a method for removing a plate-shaped polymer from the downstream end.

The method for preparing the polymerization raw material in the method of the present invention may be, but is not particularly limited to, 9 for example adding a flame retardant to the above-mentioned monomer mixture. or after dissolving the flame retardant in said monomer mixture.

A radical polymerization initiator in an amount of 0.01 to 1% by weight is added and heated at 50 to 150°C, preferably 65 to 100°C for a certain period of time, or the above-mentioned other monomers are added to the methyl methacrylate partial polymer. It can be made into a liquid or syrup by mixing and dissolving the components and the flame retardant, or by dissolving the methyl methacrylate polymer or its copolymer and the flame retardant in a mixture of methyl methacrylate and other monomers. The resin material is prepared and then a polymerization initiator is added to the resin material.
C0,01-1. OM quantity, preferably 0.02~0.
In addition, in the method of the present invention or in the resin material, the component composition of the polymer portion and the component composition of the monomer mixed portion may be different.

Although the viscosity of the polymerization raw material is not particularly limited, it is preferably about 300 to 10,000 centivoise (cp) (zo° C.) since it is injected onto the belt surface from an injection device. “If the viscosity of the polymerization raw material is too low, there is a risk that the polymerization raw material will leak from the gasket or the injection end of the belt, and if the viscosity of the polymerization raw material is too high, it may be difficult to inject onto the belt or the piping may leak. There are difficulties in handling such as the risk of polymerization within the container.

The polymerization raw material containing the flame retardant prepared as described above is then injected from an injection device located at one end of the endless belt into a molding space surrounded by both the upper and lower belts and the gasket. The polymerization raw material injected into the belt advances as the endless belt runs, and reaches the first polymerization zone (5).
It is heated to 0 to 95°C to polymerize and harden, and then heat-treated in the second polymerization zone at 100 to 160°C, leaving a residual amount of 0°C.
9, the endless belt is cooled, separated from the endless belt from the other end, and taken out as a plate-shaped product of about 0.5 to 30 mm. The polymerization time is 10 to 90 minutes in total in the first polymerization zone and the second polymerization zone. Moreover, the running speed of the endless belt is 0.5 to 4.
0m7 minutes is suitable.

In the method of the present invention, it is necessary for the polymerization raw materials injected into the opposing endless belts to enter the second polymerization zone in a state in which most of them are polymerized and cured in the first polymerization zone. The choice is very important.

In the method of the present invention, suitable known radical bonding initiators can be used, examples of which include azobisisobutyronitrile, 2,2'-azobis-2,4-
An azobis-based catalyst for dinotylvaleronitrile nato, lauroyl peroxide.

Pennzoyl peroxide, bis(:3.5.5-)
Examples include trimethylhexanoyl) oxide 1, diasilver oxide catalysts, and carbonate catalysts such as bis(4-t-butylcyclohexyl) peroxydicarbonate. Suitable polymerization initiators in the present invention include those whose decomposition temperature at a half-life of 10 hours is 30 to 90°C, preferably 40 to 80°C.Among them, 2,2'-azobis-2,4-dimethyl Valeronitrile, azobisisobutyronitrile, bis(
Particularly preferred are 3,5,5-1-limethylhexanoyl) peroxide and bis(4-1-butylcyclohexyl)peroxydicarbonate.

In the method of the present invention, it is also possible to use other known combustion agents in combination, if desired.

Further, additives such as an ultraviolet absorber, a mold release agent, a heat stabilizer, a plasticizer, a lubricant, an antistatic agent, 9 a foaming agent, 9 a dispersant, and 2 a coloring agent may be added as necessary. Additionally, aluminum hydroxide and magnesium hydroxide.

Glass fibers, inorganic fillers such as glass powder 1, powdered metals, carbon black, etc. can also be added.

Briefly, a continuous plate-making apparatus used in the method of manufacturing a sheet-like product which is a flame-retardant acrylic resin molded product of the present invention will be explained based on the drawings.

FIG. 1 shows an example for implementing the present invention. However, the continuous plate making apparatus used in the present invention is not limited to the apparatus shown in the drawings.

In the m1 diagram, (1) and (r) are endless belt belts, and the belt material is generally a metal belt made of steel or stainless steel.

These metal belts are carefully polished and, in some cases, plated to obtain a fine note of surface appearance. The thickness of the metal belt is 0, 1~3 rnrtr g
Vc O, preferably 5 to 2 mvt.

The belt is a raw pulley (2), (32 years old 6 years old (2'),
(3') and is given a predetermined tension. In the example shown in Fig. 1, hydraulic cylinders are provided at the main goose +7 (2) and (2'), and by changing the oil pressure, the tension of the belt is changed5. Methods of adjusting belt tension using springs or other mechanical methods are also known.

Although it is preferable that the belt tension be as high as possible in order to improve the belt configuration and improve the sheet thickness accuracy, the belt tension is generally operated at 3 to 15 ky/kg. - The belt is moved by driving the main pulley (3'). The belt is the main pulley (2) and (3).

The meandering can be adjusted by adjusting the angles of (2') and (3'). The meandering of the belt can also be adjusted by changing the angle of the rolls (4+, (4')) in contact with the back side of the belt or the rolls (5) provided on the return side of the belt (not shown). This shows the raw material supply process.

Monomers or partial polymers mixed with catalysts and other auxiliaries are generally fed at a constant flow rate using a metering pump. (6) is an injection device for supplying this liquid polymerization raw material to the space of the opposing belt. (7),
A gasket (7') is sandwiched between the opposing belts and runs following the running of the belts to prevent leakage of the raw material for polymerization to the outside of the belts. The gasket used is one manufactured using soft polyvinyl chloride, polyethylene/vinyl ethylene/acetate copolymer, polyurethane, or other materials.

(J, (4') shows a group of rolls with opposing belts supported from the back side.The rolls are placed in front of the polymerization zone and in the polymerization zone, where the 9M synthetic raw material passes through the space formed by the opposing belts and gaskets. It must be arranged to such an extent that no leakage occurs to the outside.

The belt flexes between adjacent rolls due to the liquid pressure of the polymerization raw material, the repulsive force of Gaskent, etc., but as this flexure increases, sheet thickness accuracy deteriorates.

Force generation 1 between the belt and the gasket
-Polymerization raw material leaks through the filter.

In some cases, outside air may enter through the rinsing gap and form bubbles in the sheet. A way to solve these problems is to suppress the deflection of the belt to a minimum, but it is desirable to narrow the roll spacing and increase the belt tension. That is, it is desirable that the distance ril# between the centers of adjacent rolls be approximately 20 to loOcm.

The rolls are set so that even when the polymerization raw material polymerizes and shrinks, it moves with the polymerization raw material and does not move away from the back surface of the belt.

(81, (8') shows a spray device a for heating a belt installed in the polymerization zone J by applying water leakage to it.The temperature of the hot water is set to any temperature below 100'C. However, in order to avoid increasing the size of the continuous polymerization apparatus and to increase productivity, it is preferable to polymerize as quickly as possible, and generally a temperature of about 50 to 95"C is used. (9) .

(9') requires a far-infrared heater provided in the second polymerization zone to heat the sheet to 100°C or higher, usually 100 to 160°C, in order to remove residual monomers.

A far-infrared heater is an effective heating means for raising the temperature of the sheet. In order to effectively utilize the amount of heat generated by the heater, it is generally covered with a thermal tact along with the belt. Once heated, the sheet passes through a heat-retaining duct so that it is maintained at the required temperature for the required time. To obtain an appropriate temperature profile, multiple far-infrared heaters can be installed as appropriate, or air can be blown into the thermal tact.

Another method 1 is also possible, for example by providing a hot air stove.

(10) and (11) indicate cooling or warming zones for cooling the sheet passed through the second polymerization zone under suitable conditions.

(12) is a sheet manufactured through the process described in 2.
Show me 4.

The method of the present invention makes it possible to continuously and highly productively make fresh flowers from flame-retardant acrylic yarn ladle moldings with excellent flame retardancy.
Koshi 2. Furthermore, in the conventional cell casting method using glass, it is not possible to produce raw n7k, but the raw j:n of long sheets and wide 11-coated sheets is industrially extremely advantageous.

With the method of the present invention, il, j, et al. A1. Rotl'14 flammable vinyl acrylic yarn (IJ1 resin molded product is made of methyl methacrylate pomopolymer or methacrylic resin used in conventional W'Jpt, 'vAB, and acrylic' resins). By using the above-mentioned resin raw material of the present invention in place of the acupuncture points of 1-kemethyl and methacrylic acid, and adding a)-logen-containing flame retardant to this, the same retardant can be obtained. It has been shown that the flame retardance of the flame retardant resin is significantly improved when compared to conventional flame retardant acrylic resins.

The acrylic resin molded product produced by the method of the present invention has excellent flammability (LRD) and physical properties, so it can be used as building materials, electrical equipment materials, signboards, glazing/glazing materials, lighting materials, etc. Useful for applications.

Hereinafter, the present invention will be explained in more detail with reference to Examples, but these are merely illustrative examples of the present invention and are not intended to limit the present invention in any way.

In Example 6, parts represent weight parts 1% and weight T (%).

In addition, physical property evaluation in Examples was measured based on the following method.

Combustion test Using the vertical method in accordance with the U.S. UL standard 5ubject 94, for a set of 5 samples (1) Burning duration (seconds) after the first 10 seconds of flame contact
and (2) the combustion duration (seconds) after the second 10-second flame contact was measured.

Example 1 In a 3000ff1 cylindrical vertical reaction tank equipped with a heating jacket, a cooling jacket, a condenser, and a vertical stirrer, 76.5% of methyl methacrylate, 3.5% of α,-methylstyrene, 10% of styrene, and anhydrous were added. maleic acid 1
1000 ml of a monomer mixture consisting of 0% was charged and heated. When the temperature of the monomer mixture was raised to 80°C, 0.25 q6 of "'''C2,2''C2,2'-azobis-2,4lonitrile was added to the monomer mixture as a polymerization initiator. It was stirred for 1 hour. The monomer mixture starts a gas reaction.

The saturation temperature was reached by the heat of polymerization, and after 15 minutes had passed since reflux started from the condenser and 1 polymerization initiator was added, the temperature was rapidly cooled until the viscosity at 20°C was 2.
A sill-like partial polymer having a conversion/unconversion rate of 610 cp, %,' was obtained.

7 parts of methacrylic acid, 20 parts of C) ζ=509 (chlorinated polyphosphate, manufactured by Daihe Kagaku Kogyo Co., Ltd.), Aerosolol OT, to 73 parts of the siliculate partial polymer prepared as described above. (dioctyl sulfosuccine)
1000 ppm and additional polymerization initiator Tojimata Tribonox 36 (bis(3,5,5-trimethylhexanoyl) peroxide, manufactured by Nouri Co., Ltd.) at a ratio of 0.4% to the resin component. and stirred to dissolve. This polymerization raw material obtained was then degassed under reduced pressure to give a finished product with a thickness of 27 g.
Belt clearer shown in Figure 1 with stainless steel belt of 7 m+ till 200 tnrn: /s 3 mm &
80° C. for 30 minutes, then removed]: (Heat-polymerized at 6° C. for 3 minutes, plate thickness 3 mm) A resin plate was obtained.

A combustion test was also conducted on this 1i fat plate. The results are shown in Table 1.

The obtained 'tWf resin plate had good transparency and a haze value (measured by ASTM Dlo()3) of 1.5 inches.

Table 1 Comparative Example 1 Only methyl methacrylate monomer was charged into the same cylindrical vertical reaction tank as in Example 1 and heated. After the temperature of the monomer was raised to 80°C, it was used as a polymerization initiator.
0.065% of 2,2'-azobis-2.4leronitrile based on the monomer was added and stirred. The monomers started a superposition reaction and reached a saturation temperature due to the heat of polymerization, and reflux started from the condenser. After 8 minutes had passed from the time when the polymerization initiator was added, the monomers were rapidly cooled. A siliculate partial polymer having a viscosity at 20"C of 1800 cp and a g-unconversion rate of 22% was obtained.

Methacrylic acid 7R (S, crt-50920
1000 pprn of Aerosolol OT and 2,2'-azobis-2,4-dimethylvaleronitrile as an additional polymerization initiator were added at a ratio of 0.083% to the resin component, and stirred. Dissolved. Next, the obtained polymerization raw material was degassed under reduced pressure, then poured into the same continuous polymerization apparatus as in Example 1 with the belt clearance set to 3 mm, and heated at 74°C for 3 minutes and then at 136°C. Heat and polymerize for 3.5 minutes to make a 3 mm thick resin plate.

A combustion test similar to that in Example 1 was conducted on this resin plate, and the results are shown in Table 2.

Table 2 Comparing Tables 1 and 2, it is found that 1. The flame-retardant acrylic resin board of the present invention is compared to the conventional flame-retardant acrylic resin board whose base polymer is a copolymer of methyl methacrylate and methacrylic acid. It is also found that its flame retardancy is very excellent.

Example 2 The viscosity at 20°C was 3570 in the same manner as Comparative Example 1.
A silica partial polymer of methyl methacrylate of cp was prepared, and 25.6 parts of α-methylstyrene and 73 parts of styrene were added to 502.6 parts of the silica partial polymer.
ffL IJ' contains 73 parts of hydromaleic acid, 70 parts of methacrylic acid, 200 parts of CR-509, Aerosolol OTI part, 363.2 parts of Trigonox and Acrivera) VH
(Mitsubishi Rayon Co., Ltd., polymethyl methacrylate powder)
55.8 parts were added and dissolved. Next, the obtained polymerization raw material was degassed under reduced pressure and injected into the continuous polymerization apparatus of Example 1 in which the belt clearance was set to 3 mm.
A resin plate having a thickness of 3 mrn was obtained by heating and polymerizing at 136° C. for 33 minutes and 3.5 minutes at 136° C. The transparency of this plate was good.

A combustion test was conducted on this resin plate, and the first and second combustion durations were measured.

However, the time was 2 seconds or less in all cases, and the flame retardancy was good.

Comparative Example 2 Methyl methacrylate monomer was added to the siliculate partial polymer of methyl methacrylate of Example 2 with a viscosity of 3570 cp to adjust the viscosity to ↓100 cp 73
0 parts to ゛C, methacrylic acid 70 parts, CR-5092
00 parts of Aerosolol OTI and 0.664 parts of 2,2'-azobis-2,4-dimethylvaleronitrile were added, stirred, and dissolved. Next, the obtained polymerization raw material was degassed under reduced pressure to reduce the belt clearance to 3 mm (
(The mixture was poured into the continuous polymerization apparatus set up in Example 1, and heated and polymerized at 74°C for 33 minutes and then at 136°C for 3.5 minutes to obtain a resin plate with a thickness of 3 mu.

A combustion test similar to that in Example 2 was conducted on this resin plate, and the results are shown in Table 3.

Table 3 Comparison of Example 2 and Comparative Example 2 (Table 3) shows that 1 the flame-retardant acrylic resin board of the present invention is different from that of the conventional flame-retardant resin board whose base polymer is a copolymer of methyl methacrylate and methacrylic acid. It is clear that the flame retardance is much superior to that of acrylic resin plates.

Example 3 8m α-methylstyrene z was added to 604 parts of the siliculate partial polymer of methyl methacrylate prepared in Example 2.
, 79 parts of styrene, 79 parts of maleic anhydride, 60 parts of methacrylic acid, 150 parts of CR-509, Aerosol OTI
After adding and dissolving 3.4 parts of 2.2'-azobis-(2,4-dimethylnocleronitrile), a resin plate having a thickness of 3 mm was obtained in the same manner as in Example 2.

When a combustion test was conducted on this resin plate, the maximum combustion duration in the first test was 2.3 seconds, and the maximum combustion duration in the second test was 4.8 seconds.

Example 4 Example 10 In a cylindrical vertical reaction tank, 76.5% of methyl methanoate and 3.5% of α-methylstyrene were added.

A monomer mixture 1000-e consisting of 10% styrene and 10% maleic anhydride was charged and heated. After the monomer mixture was heated to 80°C, it was used as a polymerization initiator (2,
0.25 parts of 2'-azobis-2,4-dimethylvaleronitrile was added to the monomer mixture and stirred. The monomer mixture started the polymerization reaction, reached a saturation temperature due to the polymerization heat, began to reflux from the condenser, and after 15 minutes had passed from the time when the 2M polymerization initiator was added, it was rapidly cooled.
A silubular partial polymer having a viscosity of 2490 cp at 20°C and a polymerization conversion of 30 was obtained.

To 73 parts of the siliculate partial polymer prepared in the above manner, 1 part of methacrylic acid (73 parts, Phosgard C-22-
R (chlorinated polyphosphonate.

Moas 7 Co., Ltd. 20 parts of IJri, 1000 ppm of dioctyl sulfosuccinate as a release agent and Tribonox 36 (bis(3,5,
5-) Limethylhexanoyl) peroxide (manufactured by Kayaku Nouri Co., Ltd.) was added at a ratio of 0.4% to the resin component and dissolved by stirring. The resulting polymerization raw material was then degassed under reduced pressure and poured into the continuous polymerization apparatus of Example 1, in which the belt clearance was set to 3 mm.

The mixture was heated and polymerized at 80° C. for 30 minutes and then at 136° C. for 3 minutes to obtain a flame-retardant acrylic resin plate having a thickness of 3 mm.

A combustion test was conducted on this resin plate. The results are shown in Table 4.

Table 4 For comparison, the same procedure as in Comparative Example 1 was carried out except that only methyl methacrylate monomer was used instead of the monomer mixture of methyl methacrylate, α-methylstyrene, styrene, and maleic anhydride. The viscosity at 20℃ is 175
0cp.

A silalag-like partial hybrid product with a polymerization conversion rate of 21% was prepared,
Using this silarag-like partial compound.

A resin plate containing Phosgard C-22-R with a plate thickness of 3 mm was obtained in exactly the same manner as in the case of the silica plate using the above monomer mixture.

A combustion test was conducted on this board, and the results are shown in Table 5.
show.

Table 5

[Brief explanation of drawings]

FIG. 1 is a side view of the entire device showing an example for implementing the present invention, (], ), (1') are endless belts, (2), (2'), (3), (3 ') represents the main pulley, (5) represents the injection device, (7) and (7') represent the gasket, and (12) represents the seat.

Claims (6)

[Claims] (1) A gasket is formed in the molding space by the opposing surfaces of two endless belts that face each other with a certain gap and run at ℃, and the gasket that runs following the belts while being sandwiched between the two belts. From the upstream end, 40 to 80 layers of methyl methacrylate or a partial polymer thereof. α-methylstyrene 1-15 t2. Styrene 5-15
Weight: 5-15% maleic anhydride and 1-15% methacrylic acid. A polymerization raw material consisting of a resin material, a nitrogen-containing flame retardant, and a polymerization initiator is supplied, and these are continuously polymerized inside the molding space. A method for producing a flame-retardant acrylic resin molded product, characterized by taking out a plate-shaped polymer from a downstream end. (2) The flame-retardant acrylic according to claim (1), wherein the halogen-containing flame retardant is at least one selected from halogen-containing condensed phosphoric acid esters and halogenated polyphosphonates. A method for producing a type 1XJ resin molded product. (3) Production of a flame-retardant acrylic resin molded product according to claim (1), wherein the M intermediate initiator is 2,2'-azobis-2,4-dimethylvaleronitrile. Method. (4) The method for producing a flame-retardant acrylic resin molded article according to claim (1), wherein the polymerization initiator is bis(3,5,5-trimethylhexanoyl) peroxide. (5) Production of a flame-retardant acrylic resin molded product according to claim (1), wherein the polymerization initiator is bis(4-t-butyl7talohexyl)baroxydicarbonate. Method. (6) The viscosity of the polymerization raw material is 300~. 10. A method for producing a flame-retardant acrylic resin molded product according to claim 1, characterized in that the molded product has a temperature of 10,100 centivoids (at 20° C.).