JP2011202094A - Flame-retardant resin composition and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant resin composition obtained by mixing and kneading a resin material, comprising cellulose-based resin and polycarbonate resin mutually incompatible, and a flame retardant, wherein the flame retardant can be contained in the cellulose-based resin at 25% or more based on the entire additive amount.SOLUTION: The method of manufacturing the flame-retardant resin composition by mixing and kneading the resin material, comprising the cellulose-based resin and polycarbonate resin mutually incompatible, and the flame retardant includes: a master batch manufacturing process in which a master batch in which the flame retardant is dispersed to the cellulose-based resin is manufactured; and a flame retardant moving process in which the manufactured master batch is mixed and kneaded with the flame retardant by a kneader 10 so that the flame retardant in the cellulose-based resin can move to the polycarbonate resin, and the moving amount is controlled.

Description

  The present invention relates to a flame retardant resin composition and a method for producing the same, and in particular, when a flame retardant is melt-kneaded into a mutually incompatible cellulose resin and a polycarbonate resin, the compatibility with the flame retardant is low. The present invention relates to a technique for containing a flame retardant at a high concentration in a cellulose resin.

  Petroleum synthetic resins such as polyethylene resins, polypropylene resins, vinyl chloride, polyamides, polystyrene resins, and PET (polyethylene terephthalate) resins are widely used as raw materials for melt molding such as injection molding raw materials and extrusion molding raw materials.

Although some of the daily necessities such as containers and films and industrial products made of such petroleum-based synthetic resins are recycled, most of them are disposed of by incineration or landfilling, thereby reducing global warming. This leads to the emission of a large amount of CO ₂ which is considered as a causative substance. Against this background, the idea of carbon neutral that does not further increase CO ₂ into the atmosphere has started to be emphasized, and substitution to a material synthesized by changing the resin material from a petroleum raw material to a natural raw material is progressing. In particular, polylactic acid resins fermented and synthesized from corn and sugarcane as raw materials have excellent mechanical properties and are most widely used. In addition, corn fermentation uses ethanol obtained as part of fuel as an alternative to gasoline.

  However, corn as a raw material grows livestock as agricultural feed or is used for food by humans. If the amount of use increases in the future, it may cause food shortages. However, there is an opinion that strictly speaking, there is no problem because edible corn is different from corn for resin raw materials. However, production in granaries such as the United States and Australia has been affected by drastic drought of corn, which can be attributed to climate change, which is thought to be due to global warming, and the impact of speculative transactions. It is also possible that there will be a problem that the distribution amount is insufficient.

  From such a background, a resin derived from a natural raw material using a non-edible raw material is required. Among these, cellulosic materials have been used for a long time, and there is no problem in supply. In addition, it has already been used in large quantities as a display material, has a sufficient track record as a normal polymer material, and has problems such as insufficient heat resistance of polylactic acid and hydrolysis in a use environment. Cellulosic resins may be solved. Therefore, there is a possibility that the application can be expanded to fields where polylactic acid resin has not been available so far.

  However, since the cellulose resin has a high melt viscosity and low fluidity, it is difficult to use it alone as a molding material, and the impact strength is weaker than that of a petroleum resin. Therefore, it is also important to change the physical properties of the cellulose resin according to the application by adding a petroleum resin having characteristics not found in the cellulose resin. Moreover, the molded article by melt molding is used for various flame retardant applications, and flame retardancy is required even when a cellulose resin is used as a molding material.

  From such a background, a flame retardant resin composition in which a cellulose resin (natural raw material), a polycarbonate resin (petroleum raw material) and a flame retardant are melt-kneaded with a kneader to add the characteristics of the polycarbonate resin to the cellulose resin. Things are being manufactured.

  However, since the cellulose resin has low compatibility with the flame retardant, it is contained in a large amount on the polycarbonate resin side when melt-kneaded, and is not sufficiently contained on the cellulose resin side. Thereby, there exists a problem that flame retardance sufficient as a flame retardant resin composition cannot be exhibited.

  Examples of techniques for incorporating a flame retardant into a resin include Patent Document 1 and Patent Document 2. In Patent Document 1, it is said that the dispersibility of the flame retardant is improved by blending the flame retardant after heating and melting the thermoplastic resin, and then melt-kneading. Moreover, patent document 2 makes a phosphazene compound (D) in a composition by making it the composition structure of a polyester resin (A), a polycarbonate resin (B), a polyester elastomer resin (C), and a phosphazene compound (D). It is said that it can be uniformly dispersed.

JP-A-8-109269 JP 2006-307178 A

  However, when a flame retardant resin composition is produced by melt-kneading a resin material of a cellulose resin and a polycarbonate resin that are incompatible with each other and a flame retardant, the methods of Patent Document 1 and Patent Document 2 are applied. However, when the compatibility between the flame retardant and the cellulose resin is low, the ratio of the flame retardant contained in the cellulose resin is reduced. In order to exhibit sufficient flame retardancy in a flame retardant resin composition containing a cellulose resin, a flame retardant is contained in the cellulose resin in the flame retardant resin composition in an amount of 25% or more of the total amount added. It is desirable that

  The present invention has been made in view of such circumstances. In a flame-retardant resin composition obtained by melt-kneading a resin material of a cellulose resin and a polycarbonate resin that are incompatible with each other and a flame retardant, cellulose Since flame retardant can be contained in the resin based on 25% or more of the total amount added, the flame retardant resin composition capable of achieving a remarkable quality improvement that has not been achieved in particular in flame retardancy and its production It aims to provide a method.

  In order to achieve the above object, the flame retardant resin composition of claim 1 is a flame retardant resin obtained by melt-kneading a resin material of a cellulose resin and a polycarbonate resin that are incompatible with each other and a flame retardant. In the composition, the flame retardant resin composition has a composition ratio of cellulose resin 60 to 80 parts by mass and flame retardant 10 to 50 parts by mass with respect to 100 parts by mass of the polycarbonate resin, and the flame retardant resin composition. The said flame retardant is contained in 25% or more of the whole addition amount in the said cellulose resin of a thing, It is characterized by the above-mentioned.

  By blending 60 to 80 parts by mass of the cellulose resin with respect to 100 parts by mass of the polycarbonate resin, it is possible to improve fluidity, dimensional accuracy, etc. at the time of molding of the flame retardant resin composition containing the cellulose resin. it can. In addition, the total amount of the flame retardant is 10 to 50 parts by mass, but there is no problem, but it is difficult for the flame retardant resin composition to increase the content in the cellulose-based resin having low compatibility with the flame retardant. It becomes important for improving flammability.

  According to the present invention, since the flame retardant is contained in the cellulosic resin of the flame retardant resin composition in an amount of 25% or more of the total addition amount, the flame retardant is not particularly achieved in the past. Quality can be improved.

  The more preferable content of the flame retardant in the cellulosic resin is 30% by mass or more of the total addition amount, and particularly preferably 34% by mass or more of the total addition amount.

  In the composition of the present invention, the flame retardant is preferably a phosphate ester or a condensed phosphate ester.

  Phosphoric acid esters or condensed phosphoric acid esters have a plasticizing function with respect to cellulosic resins, so that flame retardants are easily compatible with cellulosic resins, while improving fluidity and reducing unmelted materials. it can. As the phosphate ester, for example, triphenyl phosphate, or as the condensed phosphate ester, for example, 1,3 phenylenebis (PX-200) can be preferably used.

  In order to achieve the above object, a method for producing a flame retardant resin composition according to claim 3 is a master batch production process for producing a master batch in which a flame retardant is mixed and dispersed in a cellulose resin, and the produced master. A batch and the polycarbonate resin are melt-kneaded with a kneader so that the flame retardant in the cellulose-based resin shifts to the polycarbonate resin, and includes a flame retardant transition control step for controlling the amount of the transition. It is characterized by that.

  The inventor melts and kneads a masterbatch in which a flame retardant is mixed and dispersed only in a cellulose resin and a polycarbonate resin, and makes it difficult to transfer the flame retardant of the master batch to the polycarbonate resin during the melt kneading. It was found that a flame retardant resin composition containing 25% or more of the total amount of flame retardant in the resin can be produced. In this case, since the cellulose resin and the polycarbonate resin are incompatible resins with each other, and the flame retardant is compatible with the cellulose resin and the polycarbonate resin, the flame retardant separated from the cellulose resin is compatible with the polycarbonate resin. It is considered that it will shift.

  The present invention has been made based on such knowledge, and in the master batch manufacturing process, a master batch in which a flame retardant is mixed and dispersed only in a cellulose resin is manufactured, and when this master batch and a polycarbonate resin are melt-kneaded. The flame retardant made it difficult to migrate from the cellulose resin to the polycarbonate resin. And in the flame retardant transfer control process, the flame retardant separated from the cellulosic resin is transferred by being dissolved in the polycarbonate resin.

In the flame retardant transition control step, 270 ° C. highest softening temperature component of the softening temperature or more of the barrel temperature of the kneader the composition components below a shear rate of 30 sec ^-1 or more 436Sec ^-1 or less, a residence time It is preferable to control to 10 seconds or more and 180 seconds or less. However, the softening temperature of the cellulose resin is the softening temperature in the composition containing the flame retardant.

  Thus, after sufficient melt-kneading, the amount of the flame retardant added to the cellulose resin in the flame retardant resin composition so that the flame retardant does not shift from the cellulose resin to the polycarbonate resin too much. Since it can be made to contain 25% or more of the whole, the remarkable quality improvement which could not be achieved conventionally in a flame retardance can be aimed at. It should be noted that the amount of transfer of the flame retardant is preferably determined in advance by a preliminary test or the like in relation to the amount of transfer and the three conditions of the kneader barrel temperature, kneading speed, and residence time in the barrel.

  In the production method of the present invention, it is preferable that in the master batch production process, the cellulose resin and the flame retardant are melt-mixed and mixed and dispersed.

  Thereby, the masterbatch of the cellulose resin in which the flame retardant is mixed and dispersed at a high concentration can be produced.

  In the production method of the present invention, the flame retardant is preferably a phosphate ester or a condensed phosphate ester.

  Since the phosphate ester has a plasticizing function with respect to the cellulose resin, the flame retardant is easily compatible with the cellulose resin, and the unmelted material can be reduced. As the phosphate ester, for example, triphenyl phosphate can be suitably used.

  According to the present invention, in a flame-retardant resin composition obtained by melt-kneading a resin material of a cellulose resin and a polycarbonate resin that are incompatible with each other and a flame retardant, the flame retardant is added to the cellulose resin. Since it can be contained in an amount of 25% or more of the total amount, it is possible to achieve a remarkable quality improvement that has not been achieved in the past especially in terms of flame retardancy.

Explanatory drawing explaining the structure of the biaxial kneader which is a kneading machine used for the manufacturing apparatus of the cellulose resin composition of this invention. Explanatory drawing explaining the screw segment structure of a kneading part Table comparing Example and Comparative Example Figure showing the relationship between the content of triphenyl phosphate in polycarbonate resin and the glass transition temperature of polycarbonate resin

  Hereinafter, preferred embodiments of a flame retardant resin composition and a production method thereof will be described in detail with reference to the accompanying drawings.

  The method for producing a flame retardant resin composition of the present invention is mainly composed of a master batch production process for producing a master batch in which a flame retardant is mixed and dispersed in a cellulose resin, and the produced master batch and a polycarbonate resin in a kneader. The flame retardant in the cellulosic resin is melt-kneaded so that the flame retardant is transferred to the polycarbonate resin, and the flame retardant transfer control step for controlling the transfer amount is included.

  Thereby, a flame retardant can be contained in 25% or more of the whole addition amount in the cellulose resin of a flame retardant resin composition. Therefore, the remarkable quality improvement which was not able to be achieved in the flame retardance can be achieved. More preferably, the flame retardant content in the cellulose resin is 30% by mass or more, and particularly preferably 34% by mass or more.

  Although it does not specifically limit as a cellulose resin in this Embodiment, Diacetyl cellulose (DAC), a triacetyl cellulose (TAC), a cellulose acetate butyrate (CAB), and a cellulose acetate propionate (CAP) can be used preferably.

  Moreover, as a flame retardant, phosphate ester, for example, a triphenyl phosphate, can be used conveniently. The phosphate ester has a plasticizing function with respect to the cellulosic resin, so that the flame retardant is easily compatible with the cellulosic resin, and it is possible to improve fluidity and reduce unmelted material.

  In the master batch production process, a uniaxial kneader, a biaxial kneader, a kneader, a mixer and the like can be used, but it is particularly preferable to use a biaxial kneader. The master batch produced by the biaxial kneader is preferably discharged into a strand form from a die and then cut into master batch pellets.

  In the flame retardant transfer control step, the master batch and the polycarbonate resin are melt-kneaded with a kneader. As the kneader, a uniaxial kneader or a biaxial kneader can be used, but a biaxial kneader is particularly preferable.

  FIG. 1 is a schematic view showing the configuration of a twin-screw kneader. 1A is a side view, and FIG. 1B is a top view showing a twin screw.

  As shown in FIG. 1, two screws 14 and 14 are juxtaposed inside the barrel 12 of the twin-screw kneader 10, and each screw 14 and 14 is rotated by a motor (not shown). The two screws 14 and 14 may be rotated in the same direction or in different directions, but are preferably rotated in the same direction.

  A raw material supply port 16 is opened on the upper surface of one end side in the barrel longitudinal direction of the biaxial kneader 10, and a raw material charging hopper 18 is provided in the raw material supply port 16. The inside of the barrel 12 is divided into a transport zone 20, a kneading zone 26, and a pressure increase / discharge zone 28 in order from the hopper 18 side. In FIG. 1B, the kneading zone 26 is indicated by a square.

  Temperature adjusting means (not shown) for adjusting the temperature of each zone 20, 26, 28 is provided outside the barrel 12 constituting each zone 20, 26, 28. The temperature can be adjusted individually. As the temperature adjusting means, an electric heater or a jacket through which hot water and cold water flow can be suitably used.

  A screw element called a double thread or a single thread is provided on the screw shaft in the transport zone 20 and the pressure increase / discharge zone 28.

  On the other hand, as shown in FIGS. 2A and 2B, a plurality of screw elements called elliptical kneading disks 14B are set at equal intervals on the screw 14 in the kneading zone 26. And the rotational azimuth | direction phase of the kneading disk 14B provided in the two screws 14 and 14 is set so that it may differ continuously or periodically. The case where the phase difference is continuously shifted and the phase shift direction is forward with respect to the resin discharging direction is referred to as forward kneading as shown in FIG. The kneading disk 14B has a twist angle that twists in the same direction as the rotation direction and is sequentially shifted, and the twist angle is set to about 45 °, for example. Then, the corresponding kneading disks 14B are driven to rotate while maintaining the positional relationship in which the rotation period is shifted by 90 ° as shown in FIG.

  Also, the one where the phase difference is opposite to the resin discharge direction is called reverse kneading (not shown), and the one that is shifted periodically but has no conveying ability is neutral kneading. (Not shown). As a result, a shearing action between the surfaces of the kneading disk 14B and a dispersing action due to the turning back effect by the discontinuous kneading disk 14B are generated, and the raw materials are dispersed and mixed. In addition, the arrow of FIG. 2 (A) shows the movement of a raw material.

Further, in the twin-screw kneader 10 having the above structure, 270 ° C. highest softening temperature component of the softening temperature or more of the barrel temperatures composition material or less, it is preferable to 30 sec ^-1 or more 436Sec ^-1 or less shear rate . However, the softening temperature of the cellulose resin is the softening temperature in the composition containing the flame retardant. In general, in the twin-screw kneader 10, the barrel temperature and the shear rate are highest in the kneading zone 26, and can be rephrased as the barrel temperature and the shear rate in the kneading zone 26. Moreover, the residence time in the twin-screw kneader 10 is controlled to 10 seconds or more and 180 seconds or less.

  When the barrel temperature in the kneading zone 26 exceeds 270 ° C., the flame retardant in the master batch in which the flame retardant is mixed and dispersed in the cellulosic resin is easily transferred to the polycarbonate resin. In addition, since the cellulose resin is vulnerable to heat, it is easily colored yellow. A more preferable temperature is 240 ° C. or lower. On the other hand, when the barrel temperature is lower than the softening temperature of the component having the highest softening temperature among the composition materials, melt kneading cannot be sufficiently performed, and the quality of the flame-retardant resin composition itself cannot be ensured. However, the softening temperature of the cellulose resin is the softening temperature in the composition containing the flame retardant.

On the other hand, when the shear rate of the kneading zone 26 exceeds 436 sec ⁻¹ , the flame retardant in the masterbatch easily moves to the polycarbonate resin. In addition, since the cellulose resin is weak against heat, it is easily colored yellow by shearing heat generation. On the other hand, if the shear rate is less than 30 sec ⁻¹ , melt kneading cannot be performed sufficiently, and the quality of the flame retardant resin composition itself cannot be ensured. The shear rate here was calculated based on the clearance D of the kneading disk 14B in FIG.

  Moreover, when the residence time in the twin-screw kneader 10 exceeds 180 seconds, the flame retardant in the masterbatch is easily transferred to the polycarbonate resin. A more preferable residence time is 120 seconds or less, and particularly preferably 60 seconds or less. On the other hand, if the residence time is less than 10 seconds, melt-kneading cannot be sufficiently performed, and the quality of the flame-retardant resin composition itself cannot be ensured.

  The measurement of the residence time of the twin-screw kneader 10 is performed by, for example, putting blue resin colored blue, for example, directly above the screw 14 from the hopper 18 during the operation of the twin-screw kneader 10 and setting the charging time to 0 second. And And the strand extruded from the die attached to the tip of the biaxial kneader 10 is sampled every 10 seconds to measure the bluish color, and the sampling time of the bluest strand is defined as the residence time in the biaxial kneader 10 To do.

  Therefore, within the range of the above three transition amount control conditions, a transition that can contain 25% or more of the total amount of the flame retardant in the cellulose resin of the flame retardant resin composition by a preliminary test or the like. The amount control condition may be obtained.

  Including the flame retardant contained in the cellulosic resin of the flame retardant resin composition produced in the examples satisfying the production method of the flame retardant resin composition of the present invention and the comparative example not satisfying The percentage of the total amount added was examined. In addition, the quality of the flame-retardant resin composition produced was examined. As the quality, three items of flame retardancy, unmelted material, and coloring were evaluated.

[material]
Polycarbonate resin (PC), cellulose acetate (AC), which is a cellulosic resin, and triphenyl phosphate (TPP), which is a flame retardant having a plasticizing function, have the following composition ratios in both Examples and Comparative Examples. The raw material was adjusted as follows.
-Polycarbonate resin (PC) ... 50 parts by mass-Cellulose acetate (AC) ... 35 parts by mass-Triphenyl phosphate (TPP) ... 15 parts by mass [Test]
In the embodiment, a master in which cellulose acetate and triphenyl phosphate are melt-kneaded using a twin-screw kneader, discharged in a strand form from a die, and then cut to mix and disperse triphenyl phosphate in cellulose acetate. Batch pellets were produced. And this master batch pellet and polycarbonate resin were melt-kneaded with the biaxial kneader 10 shown in FIG.

  In the comparative example, the polycarbonate resin, cellulose acetate, and triphenyl phosphate were directly melt-kneaded by the biaxial kneader 10 shown in FIG.

In both the examples and the comparative examples, the conditions of the biaxial kneader 10 were a barrel temperature of 220 ° C., a shear rate of 260 sec ⁻¹ , and a residence time of 40 seconds.

[Evaluation items for flame retardant resin composition]
<Flame retardance test: UL94-V>
A test piece of a flame retardant resin composition having a length of 127 mm, a width of 12.7 mm, and a thickness of 1.6 mm was formed by injection molding of the flame retardant resin composition described in the examples, and the test piece was flame retardant. It used as a test piece of a property test. UL94-V is the most basic flammability test for plastic parts and the like, and the degree of combustion of the test piece is examined by applying a flame of a gas burner to a test piece having a specified size. The grades are 5VA, 5VB, V-0, V-1, V-2, and HB in descending order of flame retardancy. The flame retardance of V-1 or higher is regarded as acceptable (O), and V- A flame retardance of 2 or less was regarded as rejected (x).

<Unmelted material test>
If the number of unmelted materials in the strand discharged from the strand die (after cooling) was 2 or less per 10 cm of strand, it was determined to be acceptable (◯), and more than 2 was regarded as unacceptable (x). The unmelted material can be confirmed as a protrusion protruding on the surface when the composition is touched by hand. In addition, in the case of x to ◯ in the evaluation, it indicates that there are cases where the test passes and a case where the test fails.

<Coloring test>
When the yellow index (YI value) of the flame retardant resin composition described in the examples is 50 or less, it is evaluated as ◯, and when it exceeds 50, it is evaluated as ×.

[Test results]
The test results are shown in the table of FIG.

<Flame retardant content in cellulosic resin>
As can be seen from the table in FIG. 3, in the example, the content of triphenyl phosphate contained in the cellulosic resin in the flame-retardant resin composition produced was 34.2% of the total amount added. It was. The content rate of 34.2% in this example sufficiently satisfies 25% or more, which is a desired value for causing the flame retardant resin composition containing the cellulose resin to exhibit sufficient flame retardancy.

  In contrast, in the comparative example, the content of triphenyl phosphate contained in the cellulosic resin was 22.7% of the total addition amount, and the desired value of 25% was not achieved.

  As can be seen from the comparison between the above examples and comparative examples, the present invention provides a flame retardant resin composition obtained by melting and kneading a flame retardant into a mutually incompatible cellulosic resin and a polycarbonate resin. A flame retardant can be contained in 25% or more of the total addition amount in a cellulose resin having low compatibility.

  Thereby, the remarkable quality improvement which could not be achieved conventionally especially in the flame retardance was able to be aimed at.

  In addition, the content rate of the triphenyl phosphate in a cellulose resin was computed as follows using the glass transition temperature (Tg) derived from a polycarbonate resin. Hereinafter, the calculation method will be described in the case of the embodiment.

In calculating, the following three points are preconditions. That is,
I) Since polycarbonate resin and cellulose acetate are incompatible resins with each other, Tg derived from polycarbonate resin and Tg derived from cellulose acetate are not affected by melt-kneading.

  II) FIG. 4 shows the relationship between the triphenyl phosphate blending ratio and the Tg of the polycarbonate resin when the blending amount of the triphenyl phosphate in the polycarbonate resin is changed, and there is a linear relationship.

  III) The total amount of added triphenyl phosphate remains in the flame retardant resin composition which is the final composition.

And based on the said premise, it computed as follows. That is,
A) Tg derived from the polycarbonate resin in the flame-retardant resin composition produced was determined by differential scanning calorimetry (DSC measurement). The measurement result was 77.0 ° C. as shown in the table of FIG.

  B) Next, the mass% of triphenyl phosphate contained in the polycarbonate resin was determined from the conversion formula shown in FIG. 4, Y = −0.2169X + 33.192. The result was 16.5% by mass as shown in the table of FIG.

  C) Next, the mass% of triphenyl phosphate contained in cellulose acetate was calculated as follows.

  That is, the above 16.5% by mass is the ratio of the mass part of triphenyl phosphate to the total value of the mass part of polycarbonate resin and the mass part of triphenyl phosphate, so that the remaining 83.5% of 16.5% by mass is 83.5%. The mass% is 50 parts by mass of the polycarbonate resin shown in the composition column of the table of FIG. Therefore, the total mass part of the polycarbonate resin and the triphenyl phosphate contained therein is 59.9 parts by mass from (Formula 1).

50 / (1-0.165) ... Formula 1
Moreover, since 50 mass parts among said 59.9 mass parts is polycarbonate resin, the triphenyl phosphate contained in polycarbonate resin will be 9.9 mass parts.

  D) Next, since the total amount of triphenyl phosphate added from the column of the composition in the table of FIG. 3 is 15 parts by mass, 5.1 parts by mass obtained by subtracting 9.9 parts by mass from 15 parts by mass Becomes part by mass of triphenyl phosphate contained in cellulose acetate.

  E) Next, 5.1 parts by mass of the triphenyl contained in the cellulose acetate based on the total value of the parts by mass of triphenyl phosphate and the parts by mass of cellulose acetate from the formula 2 When converted to the mass% of phosphate, it becomes 12.8 mass% in the table of FIG.

[5.1 / (35 + 5.1)] × 100 Formula 2
Moreover, when 5.1 parts by mass is converted into the ratio of triphenyl phosphate contained in cellulose acetate according to Formula 3, it is 34.2% in the table of FIG. And this numerical value means that the content rate of the flame retardant contained in the cellulosic resin in the produced flame retardant resin composition is 34.2% of the total amount added.
(5.15 / 15) × 100 Formula 3
For the comparative example, the ratio of triphenyl phosphate contained in the cellulose acetate is 22.7% in the table of FIG. 4 by calculating in the same manner as in the above example.

<Quality evaluation of manufactured flame-retardant resin composition>
As can be seen from the table in FIG. 3, in the examples, the flame retardancy was evaluated as V-0, the unmelted product was evaluated as ○, and the coloring was evaluated as ○, and all items passed.

  On the other hand, in the comparative example, the flame retardancy is an evaluation of V-2, the unmelted product is an evaluation of × to ○, and the coloring is an evaluation of ○, and in particular, the flame retardancy is considerably inferior to the examples. It became. The reason for this is considered that the comparative example has a considerably lower triphenyl phosphate content in the cellulosic resin than the examples, as described above.

  DESCRIPTION OF SYMBOLS 10 ... Kneading machine (biaxial kneader), 12 ... Barrel, 14 ... Screw, 14A ... Screw shaft, 14B ... Kneading disk, 16 ... Raw material supply port, 18 ... Hopper, 20 ... Conveying zone, 26 ... Kneading zone, 28 ... Pressure increase / discharge zone

Claims (6)

In a flame-retardant resin composition formed by melt-kneading a resin material of a cellulose resin and a polycarbonate resin that are incompatible with each other, and a flame retardant,
While the flame retardant resin composition is a composition ratio of cellulose resin 60 to 80 parts by mass and flame retardant 10 to 50 parts by mass with respect to 100 parts by mass of the polycarbonate resin,
The flame retardant resin composition, wherein the flame retardant resin composition contains 25% or more of the flame retardant in the cellulose resin of the flame retardant resin composition.   The flame retardant resin composition according to claim 1, wherein the flame retardant is a phosphate ester. A master batch production process for producing a master batch in which a flame retardant is mixed and dispersed in a cellulose-based resin;
A flame retardant transition control step for melt-kneading the produced master batch and the polycarbonate resin with a kneader so that the flame retardant in the cellulose resin migrates to the polycarbonate resin and controls the amount of migration. And a method for producing a flame retardant resin composition. In the flame retardant transfer control step, the barrel temperature of the kneader is set to the softening temperature of the component having the highest softening temperature among the composition components (however, the softening temperature of the cellulose resin is the softening temperature in the composition containing the flame retardant). to) more than 270 ° C. or less, a shear rate of 30 sec ^-1 or more 436Sec ^-1 or less, the flame-retardant resin composition according to claim 3, wherein the controlling the residence time 180 seconds or less 10 seconds or more Production method.   5. The production of a flame retardant resin composition according to claim 3, wherein in the master batch production step, the cellulose resin is melted, and the flame retardant is mixed and dispersed in the melted cellulose resin. Method.   The method for producing a flame retardant resin composition according to claim 3 or 4, wherein the flame retardant is a phosphate ester.

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