JP3428749B2 - Method for regenerating aromatic polycarbonate resin - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for remanufacturing a resin composition using an unnecessary compact disc material, and more particularly to a method for remanufacturing a resin composition excellent in fluidity, impact resistance and heat resistance. Is. Compact discs are used by many users, and the volume produced is increasing year by year. Therefore, there are an increasing number of unnecessary compact discs that are no longer used, compact discs that are returned from retailers, and so-called compact discs that should be reproduced, such as defective products that occur during production. It is being appreciated.

The present invention seeks to recycle an unnecessary compact disc from the viewpoint of effective use of resources and environmental protection.

[0003]

2. Description of the Related Art Conventionally, as a method of recycling a compact disc molded from an aromatic polycarbonate resin,
Aluminum film, ink, attached to the compact disc,
A method of removing the UV coating film and reusing the resin of the substrate has been considered. However, as a method for removing these aluminum film, ink, UV coating film, etc., a physical method such as a method for polishing cutting glass on the surface of a compact disc, a method for compressing by vibration, or a chemical method using acid, alkali or the like is available. It's possible, but all were expensive and uncommon. Also, if the aluminum film, ink, UV coating film, etc. adhering to the compact disc are not removed and crushed and used as they are, the aromatic polycarbonate resin which is the substrate is thermally decomposed when staying in the extruder for a long time, and the viscosity average The molecular weight is lowered and the mechanical properties of the resin are lowered. As a result, there is a problem that the heat-deteriorated product is mixed into the product when the brand of the resin is changed and the yield is reduced.

[0004]

DISCLOSURE OF THE INVENTION The present invention is a method for regenerating an aromatic polycarbonate resin composition having excellent fluidity, impact resistance and heat resistance using an unnecessary compact disc material molded from an aromatic polycarbonate resin. To provide.

[0005]

The object of the present invention is (A)
Compact disc material whose substrate is an aromatic polycarbonate resin 1 to 99% by weight (a component) and (B) an aromatic polycarbonate resin having a viscosity average molecular weight of 17,000 to 60,000 99 to 1% by weight (b component) This is achieved by a method for regenerating an aromatic polycarbonate resin composition, characterized in that the resin regenerated by melt-kneading the substantially resin composition has a viscosity average molecular weight of 16,500 to 35,000. This recycling method is less laborious than conventional methods and can be recycled at low cost, and the aromatic polycarbonate resin resin composition recycled by this recycling method has fluidity, impact resistance, and heat resistance. Is excellent.

The compact disc material (component a) in which the (A) substrate used in the present invention is an aromatic polycarbonate resin is a so-called defective product, returned product, or recovery product which is generated from any route from the production of the compact disc to its sale. A compact disc that is no longer needed. The compact disc material to be regenerated may be roughly crushed in advance, or may be in a disc-like shape as it is. Further, an aluminum film, ink, a UV coating film or the like may be attached. Compact disc material (10
The amount of aromatic polycarbonate in (0% by weight) is 90% by weight or more, preferably 95% by weight or more, more preferably 9% by weight or more.
It is 9% by weight or more.

The aromatic polycarbonate resin used for the substrate of the compact disc material is derived from dihydric phenol. It is usually obtained by reacting a dihydric phenol with a carbonate precursor by a solution method or a melting method. Examples of the dihydric phenol used here include 2,2-bis (4-hydroxyphenyl) propane (hereinafter abbreviated as bisphenol A), bis (4-hydroxyphenyl) methane, and 2,2-bis (4-hydroxy). −
3,5-Dimethylphenyl) propane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4
Bis (4-hydroxyphenyl) alkane such as -hydroxy-3-methylphenyl) propane and bis (4-)
Examples thereof include hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) alkane is preferable, and bisphenol A is particularly preferable. Further, examples of the carbonate precursor include carbonyl halide, diaryl carbonate, haloformate and the like, and specific examples thereof include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol and a mixture thereof. In producing the aromatic polycarbonate resin, the above dihydric phenols may be used alone or in combination of two or more kinds. Further, an appropriate molecular weight regulator, branching agent, catalyst for accelerating the reaction and the like can also be used. It is no problem to mix two or more of the aromatic polycarbonate resins thus obtained. Usually, the viscosity average molecular weight is 14,000 to 16,0.
Those of about 00 are generally used.

The term "viscosity average molecular weight" as used herein means an average molecular weight M obtained from the following relational expression using [η] obtained by using methylene chloride as a solvent at 20 ° C.

[Η] = 1.23 × 10 ⁻⁴ M ^0.83 On the other hand, (B) the viscosity average molecular weight of the present invention is 17,000 to 6
The aromatic polycarbonate resin (component (b)) of 10,000 is derived from a dihydric phenol. It is usually obtained by reacting a dihydric phenol with a carbonate precursor by a solution method or a melting method. The dihydric phenol used here is, for example, 2,2-bis (4-hydroxyphenyl) propane (hereinafter abbreviated as bisphenol A), bis (4
-Hydroxyphenyl) methane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 1,
1-bis (4-hydroxyphenyl) ethane, 2,2-
Examples thereof include bis (4-hydroxyphenyl) alkane such as bis (4-hydroxy-3-methylphenyl) propane and bis (4-hydroxyphenyl) sulphone, and bis (4-hydroxyphenyl) alkane is preferable, and among them, Bisphenol A is particularly preferred. Also,
Examples of the carbonate precursor include carbonyl halide, diaryl carbonate, haloformate and the like, and specific examples include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol and a mixture thereof.
In producing the aromatic polycarbonate resin of component a and component b, the dihydric phenol may be used alone or in combination of two or more. Further, the aromatic polycarbonate resin of the component a and the component b is preferably a polycarbonate resin from the same type of dihydric phenol, and particularly preferably a polycarbonate resin from bisphenol A. Appropriate molecular weight regulators, branching agents, catalysts for accelerating the reaction and the like can be used in such resins. Two or more of the aromatic polycarbonate resins thus obtained may be mixed.

The aromatic polycarbonate resin which is the component b of the present invention may be in the form of pellets, powder or a mixture thereof.

The viscosity average molecular weight of the aromatic polycarbonate resin as the component b is 17,000 to 60,000, preferably 20,000 to 50,000, and more preferably 23,000 to 40,000. When the total amount of the a component and the b component is 100% by weight, the ratio of the b component is 1 to
It is 99% by weight. It is preferably 10 to 90% by weight, more preferably 20 to 80% by weight. If it is less than 1% by weight, the molecular weight of the aromatic polycarbonate resin composition regenerated by the method of the present invention decreases, resulting in insufficient heat resistance and impact resistance. On the other hand, if it exceeds 99% by weight, the molecular weight becomes too high and the fluidity becomes insufficient.

Examples of the phosphorous acid ester of the component c-1 used in the present invention include triphenyl phosphite, distearyl pentaerythritol diphosphite, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl). ) Phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl-monophenyl phosphite, dioctyl-monophenyl phosphite, diisopropyl-
Monophenyl phosphite, monobutyl-diphenyl phosphite, monodecyl-diphenyl phosphite, monooctyl-diphenyl phosphite, bis (2,6-
Di-tert-butyl-4-methylphenyl) pentaerythritol-di-phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octylphosphite, bis (nonylphenyl) pentaerythritol diphosphite A bis (2,4-di-tert-butylphenyl) -4,4-diphenylenephosphonite or other triester of phosphorous acid or a diester in which the ester moiety is substituted with an alkyl group, a phenyl group, an alkylaryl group, or the like, These are monoesters, and these may be used alone or in combination of two or more kinds. Of these, trisnonylphenyl phosphite and distearyl pentaerythritol diphosphite are preferable.

Examples of the c-2 component phosphoric acid ester used in the present invention include tributyl phosphate, trimethyl phosphate, tricresyl phosphate, triphenyl phosphate, trichlorophenyl phosphate, triethyl phosphate, diphenyl cresyl phosphate,
Examples thereof include diphenyl monoorthoxenyl phosphate, tributoxyethyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate, and the like, which may be used alone or in combination of two or more kinds. Of these, triphenyl phosphate and trimethyl phosphate are preferable.

The amount of the phosphorous ester of the c-1 component and / or the phosphoric ester of the c-2 component used in the present invention is 0.005 when the total amount of the a component and the b component is 100 parts by weight.
2.0 parts by weight. The amount is preferably 0.008 to 1.8 parts by weight, more preferably 0.01 to 1.5 parts by weight.
By blending the phosphite ester and / or the phosphoric acid ester, the thermal stability of the regenerated aromatic polycarbonate resin composition is improved and the decrease in the viscosity average molecular weight can be suppressed. The amount of this c-1 component and / or c-2 component is 0.005
If it is less than parts by weight, the effect on the thermal stability is small, and if it exceeds 2.0 parts by weight, the physical properties (impact resistance, rigidity, etc.) of the regenerated resin composition are adversely affected.

The composition of the present invention can be molded as it is,
Further, a coloring agent may be added. If the compact disc to be played has an aluminum film, the aluminum film will shine and give a beautiful metallic appearance. In particular, it is preferable to use a dye-based coloring agent in order to obtain a transparent and beautiful metallic appearance. In addition, the composition of the present invention may contain an effective amount of additives within a range that does not impair the purpose. For example,
Other stabilizers, impact modifiers, release agents, ultraviolet absorbers, antistatic agents, flame retardants, plasticizers, lubricants and the like may be added.

In the present invention, a method for melt-kneading the resin composition from the components a and b and optionally c-1 and / or component c-2 is a single-screw extruder, a twin-screw extruder,
A generally used one such as a pressure kneader can be used. Particularly preferred is a twin-screw extruder with a vent,
It is preferable that the vent can be evacuated. In this case, it is preferable that the compact disk material (component a) whose substrate (A) is an aromatic polycarbonate resin is pulverized to have a particle diameter of 30 mm or less. If it is not pulverized, it becomes difficult to supply it to an extruder or the like used when melt-kneading. However, the particle size here means the major axis of the pulverized product. The raw materials to be used may be mixed in advance with a tumbler, a blender, a Nauter mixer, a Banbury mixer, a kneading roll or the like, or may be independently supplied using a measuring machine.

The recycling method of the present invention intends to recycle unnecessary compact discs from the viewpoint of effective utilization of resources and environmental protection. The aromatic polycarbonate resin composition regenerated by this method is flowable. Excellent in heat resistance and impact resistance. The aromatic polycarbonate resin composition of the present invention is useful for parts such as OA parts, home appliances, audio parts, and miscellaneous parts.

[0018]

Examples 1 to 6 and Comparative Examples 1 and 2 The present invention will be further described with reference to the following examples. After mixing the components listed in Table 1 with a tumbler in the proportions listed in Table 1, melt-kneading at a cylinder temperature of 280 ° C. while evacuating the vents using a single-screw extruder with a vent having a diameter of 30 mmφ (VSK30 type, Central Machinery Works) and extruding. Pelletized. This pellet at 120 ℃
After drying for 5 hours, injection molding machine [Sumitomo Heavy Industries S480 /
150] and the resin composition before melt extrusion were evaluated by the following methods. The evaluation results are shown in Table 2.

Viscosity average molecular weight: 5 g of resin before melt extrusion and after 10 minutes residence in an injection molding machine was added with 10 methylene chloride.
It was dissolved in 0 g, measured using an Ostwald viscometer, and calculated by the formula described on page 4 of the specification. Reduction rate of molecular weight: (MW2-MW1) / MW1 × 100
(%) Here, MW1 is a viscosity average molecular weight before melt-kneading, and MW2 is a viscosity average molecular weight after staying for 10 minutes in an injection molding machine. Flowability: Melt flow rate Measured under conditions of a load of 2.16 kgf and a temperature of 280 ° C. according to JIS K-7210. Impact strength with Izod notch: thickness of measured test piece 3.2
mm and measured according to ASTM D-256. Deflection temperature under load: Measured according to JIS K-7207 under a load of 18.5 kgf / cm ² . Appearance: visually determined. Transparent: A test piece with a thickness of 5 mm is placed on a black character so that the character can be read. A little metallic: The character can be read faintly, but the surface is metallic. Metallic: The surface has a metallic luster. No letters are visible.

The symbols showing the components shown in Table 1 are as follows. <Component a> CD: Compact disc material [Product] The substrate is bisphenol A with a viscosity average molecular weight of 15,000.
Aromatic polycarbonate, the amount of which is 99.6% by weight in a compact disc. Diameter of aluminum film attached 1
Compact disc material with an average particle size of 6 mm obtained by pulverizing a 20 mm compact disc with a pulverizer. <Component b> PC-1: Bisphenol A aromatic polycarbonate resin powder (viscosity average molecular weight: 24,000) PC-2: Bisphenol A aromatic polycarbonate resin pellet (viscosity average molecular weight: 30,000) PC-3: Bisphenol A aromatic polycarbonate resin pellets (viscosity average molecular weight: 15,000) <c-1 component> Stabilizer: trimethyl phosphate <coloring material> Perinone red dye [Plastread 8370, Arimoto Chemical Industry Co., Ltd.]

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

According to the present invention, there is provided a method for reusing waste compact discs formed of an aromatic polycarbonate resin which is labor-saving and low in cost. From the standpoint of environmental protection, it is excellent for recycling unnecessary compact discs. Further, it becomes possible to provide a regenerated resin composition of an aromatic polycarbonate resin excellent in fluidity, impact resistance, and heat resistance, which is regenerated by the recycling method in a metallic tone, and an industrial effect of the present invention. Is exceptional.

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Claims (2)

(57) [Claims] 1. A compact disc material whose substrate (A) is an aromatic polycarbonate resin is 1 to 99% by weight (component a) and (B) has a viscosity average molecular weight of 17,000 to 60,
000 aromatic polycarbonate resins 99-1% by weight
The viscosity average molecular weight of the resin regenerated by melt-kneading the resin composition substantially consisting of (b component) is 16,500 to 35,
000, and a method for regenerating an aromatic polycarbonate resin composition. 2. When the total amount of the component a and the component b according to claim 1 is 100 parts by weight, (C) the phosphite ester (c-1)
Component) and / or phosphoric acid ester (c-2 component) is 0.0
The method for regenerating an aromatic polycarbonate resin composition according to claim 1, wherein the resin composition is in a range of 05 to 2.0 parts by weight.