JP2012233030A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition that suppresses the occurrence of molding failure, such as short shot, in an obtained molding and has excellent flame retardancy.SOLUTION: The resin composition includes a thermoplastic polyester resin and/or a polycarbonate resin and a flame retardant and is used for injection molding, and satisfies conditions (1) to (3): (1) the viscosity at a temperature equal to or higher than HDT (heat deflection temperature)-50 (°C) and equal to or lower than HDT (°C) is equal to or more than 10(Pa s) and less than 10(Pa s); (2) the viscosity at a temperature equal to or higher than HDT+150 (°C) and equal to or lower than HDT+250 (°C) is equal to or more than 10(Pa s) and less than 10(Pa s); and (3) assuming the viscosity at HDT (°C) is N1 (Pa s) and the viscosity at HDT+150 (°C) is N2 (Pa s), relational expression (1), 0<N1-N2<10, is satisfied.

Description

  The present invention relates to a resin composition for injection molding mainly composed of a thermoplastic polyester resin and / or a polycarbonate resin.

  At present, thermoplastic resins such as polyester resins and polycarbonate resins and resin compositions thereof are used in containers, from the viewpoint of excellent molding processability, mechanical properties, heat resistance, weather resistance, appearance, hygiene and economy. It is used in a wide range of fields as molding materials for packaging films, home appliances, OA equipment, AV equipment, electrical / electronic parts, and automotive parts. For this reason, the amount of such a thermoplastic resin and molded product of the resin composition used is large, and is increasing year by year. Accordingly, the amount of molded processed products that have been used and discarded is increasing, which is a serious social problem.

  In recent years, laws such as “Act on the Promotion of Separate Collection and Recycling Related to Containers and Packaging (Container and Packaging Recycling Law)” and “Act on Promotion of Procurement of Environmental Goods by the Countries (Green Purchasing Law)” With successive enforcement, interest in material recycling technology for molded products of such thermoplastic resins and resin compositions has increased. In particular, there is an urgent need to establish a material recycling technology for PET bottles using polyethylene terephthalate (hereinafter also referred to as “PET”) resin, whose usage is rapidly increasing. In addition, with the widespread use of optical recording medium products (optical discs) made of polycarbonate (hereinafter also referred to as “PC”) resin such as CD, CD-R, DVD, and MD, they are discharged during molding. Studies have been made on methods of reusing mill ends and methods of reusing PC resin obtained after peeling off a reflective layer, a recording layer, etc. from an optical disc that has become waste.

When re-molding a resin obtained by pulverizing a molded product of PET resin such as used PET bottles collected from the market or PC resin such as an optical disk, especially when re-molding by injection molding, heat resistance and production In order to improve the properties, the crystallization speed of the resin is increased (for example, see Patent Document 1).
However, only by increasing the resin crystallization speed, there are problems such as molding defects such as short shots in the resulting molded product and problems in that the temperature margin during molding is narrow.
Here, the short shot refers to a molding defect that is molded in an incomplete shape state in an injection molding method and a part of the resulting molded product is missing.

  Further, when a thermoplastic resin such as a polyester resin or a polycarbonate resin and a resin composition thereof are used for a constituent member such as a home appliance or an OA device, it is required to have sufficient flame retardancy.

JP 2007-269019 A

  The present invention has been made in consideration of the above circumstances, and its purpose is to short-circuit the obtained molded product even when the regenerated polyester resin or polycarbonate resin is molded again by the injection molding method. An object of the present invention is to provide a resin composition that suppresses the occurrence of molding defects such as shots and has excellent flame retardancy.

The resin composition of the present invention is a resin composition for injection molding containing a thermoplastic polyester resin and / or a polycarbonate resin and a flame retardant,
The following conditions (1) to (3) are satisfied.
Condition (1): Viscosity in the range of temperature (HDT-50 [° C.]) or more and (HDT [° C.]) or less is 10 ¹ (Pa · s) or more and less than 10 ⁶ (Pa · s) (provided that “HDT” indicates the deflection temperature under load of the resin composition.
Condition (2): The viscosity in the range of temperature (HDT + 150 [° C.]) or more and (HDT + 250 [° C.]) is 10 ⁻² (Pa · s) or more and less than 10 ¹ (Pa · s).
Condition (3): When the viscosity at HDT [° C.] is N1 (Pa · s) and the viscosity at (HDT + 150 [° C.]) is N2 (Pa · s), relational expression (1); 0 <N1-N2 <10 ⁴ must be satisfied.

  The resin composition of the present invention is obtained through a gap passing treatment in which a molten polymer kneaded material containing a thermoplastic polyester resin and / or a polycarbonate resin and a flame retardant is passed through a slit having a gap distance of less than 5 mm. It is preferable that

  According to the resin composition of the present invention, when the resin composition contains a flame retardant and has a specific viscosity, the recycled polyester resin or polycarbonate resin is molded again by an injection molding method. However, in the obtained molded product, occurrence of molding defects such as short shots is suppressed, and excellent flame retardancy is obtained.

It is explanatory drawing which shows one structural example of the apparatus (die | dye) used for the specific clearance passage process for obtaining the resin composition of this invention, (a) is a perspective top view, (b) is P- It is Q line sectional drawing. It is a graph which shows the viscosity curve of the resin composition which concerns on Example 1 and Comparative Example 5.

  Hereinafter, the present invention will be described in detail.

(Resin composition)
The resin composition of the present invention is for injection molding containing at least a thermoplastic polyester resin and / or a polycarbonate resin and a flame retardant.
Hereinafter, the components of the resin composition of the present invention will be described in detail.

[Thermoplastic polyester resin and / or polycarbonate resin]
A thermoplastic polyester resin and / or a polycarbonate resin (hereinafter also referred to as “component (A)”) is the main component constituting the resin composition of the present invention.

(Thermoplastic polyester resin)
The thermoplastic polyester resin as the component (A) is not particularly limited, and a polyester resin (hereinafter also referred to as “recycled polyester resin”) obtained from a molded product that has been used and discarded. In addition, those obtained by polycondensation of a derivative having dicarboxylic acid or ester-forming ability and a diol or ester-forming derivative by a known method can also be used.

  Specific examples of the dicarboxylic acid for forming the thermoplastic polyester resin as the component (A) include, for example, terephthalic acid, isophthalic acid, orthophthalic acid, 2,2′-biphenyldicarboxylic acid, and 3,3′-biphenyldicarboxylic acid. Acid, 4,4'-biphenyl dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, bis (p-carboxyphenyl) ) Aromatic dicarboxylic acids such as methane, anthracene dicarboxylic acid, sodium 5-sulfoisophthalate, adipic acid, sebacic acid, succinic acid, azelaic acid, malonic acid, oxalic acid, dodecanedioic acid, etc. 1,3 -Cyclohexanedicarboxylic acid, 1,4-cyclohexane Alicyclic dicarboxylic acids and ester-forming derivatives thereof such as carboxylic acids (e.g. methyl ester, such as lower alkyl esters such as ethyl ester), and dicarboxylic acids derived from such. These can be used alone or in combination of two or more.

  Specific examples of the diol for forming the thermoplastic polyester resin as the component (A) include, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-propanediol, 1, 2 to 10 carbon atoms such as 4-butanediol, 2,3-butanediol, 1,6-hexanediol, 1,10-decanediol, neopentyl glycol, 2-methylpropanediol, 1,5-pentadiol, etc. Polyaliphatic diols such as aliphatic diol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, polyethylene having a molecular weight of 6000 or less such as diethylene glycol, polyethylene glycol, poly-1,3-propylene glycol, polytetramethylene glycol From alkylene glycol etc. Diols guiding the like. These can be used alone or in combination of two or more.

  The thermoplastic polyester resin as the component (A) constituting the resin composition of the present invention is 1 mol% or less based on the total structural units, for example, glycerin, trimethylolpropane, pentaerythritol, trimellitic acid, It may have a structural component derived from a trifunctional or higher functional monomer such as pyromellitic acid.

  A thermoplastic polyester resin is obtained by polycondensation of an aromatic dicarboxylic acid or a derivative having ester-forming ability and an aliphatic diol or a derivative having ester-forming ability from the viewpoint of further improving mechanical strength and flame retardancy. The aromatic polyester resin is preferably used.

  Specific examples of the thermoplastic polyester resin include, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polypropylene terephthalate, polyethylene naphthalate (PEN), polybutylene naphthalate, poly-1,4-cyclohexanedimethylene terephthalate. , Polycaprolactone, p-hydroxybenzoic acid-based polyester, polyarylate-based resin, and the like. Among these, PET and PEN using ethylene glycol as the diol component are particularly preferable from the viewpoint of balance of physical properties such as crystallization behavior, thermal properties, and mechanical properties.

The thermoplastic polyester resin as the component (A) preferably has an intrinsic viscosity of 0.5 to 1.5 dl / g, more preferably 0.65 to 1.30 dl / g.
When the intrinsic viscosity of the thermoplastic polyester resin is too low, sufficient impact resistance cannot be obtained, and chemical resistance may be lowered.
On the other hand, when the intrinsic viscosity of the thermoplastic polyester resin is excessive, the flow viscosity increases and the kneading temperature is set high in the (I) melting / kneading process described later, which affects other additives. There is a fear.
This intrinsic viscosity is a value when measured at 30 ° C. using a mixed solvent of phenol / tetrachloroethane (mass ratio: 1/1).

  The thermoplastic polyester resin as the component (A) preferably has a melting point of 180 to 300 ° C, more preferably 220 to 290 ° C, and a glass transition temperature of 40 to 200 ° C. It is preferable that it is a thing of 50-150 degreeC.

  The melting point of this thermoplastic polyester resin is measured using a differential scanning calorimeter “DSC7020” (manufactured by Seiko Instruments Inc.), and the melting point is a crystal that appears during temperature rise measurement by the differential scanning calorimeter. It shall mean the end point temperature of the melting endothermic peak.

The glass transition temperature of this thermoplastic polyester resin is measured using a differential scanning calorimeter “DSC7020” (manufactured by Seiko Instruments Inc.).
Specifically, 10 mg of a measurement sample (thermoplastic polyester resin) is precisely weighed to two digits after the decimal point and set in an aluminum pan. The reference uses an empty aluminum pan, performs heat-cool-heat temperature control at a measurement temperature of 0 to 200 ° C., a temperature increase rate of 10 ° C./min, and a temperature decrease rate of 10 ° C./min. Analysis is performed based on the data in Heat. The glass transition temperature in the present invention refers to the temperature of the portion where the base line changes stepwise. That is, the temperature at the intersection of a straight line that is equidistant from the straight line extending from each base line before and after the stepped portion and the curve of the stepped portion.

  (A) It is preferable that content of the thermoplastic polyester resin as a component is 10-80 mass% with respect to the resin composition whole quantity, More preferably, it is 10-70 mass%.

(Polycarbonate resin)
The polycarbonate resin as the component (A) is not particularly limited, and a polycarbonate resin obtained from a molded processed product that has been used and discarded (hereinafter also referred to as “recycled polycarbonate resin”) is used. Can do.
Moreover, as a polycarbonate resin as (A) component, what is obtained by reacting a bivalent phenol and a carbonate precursor can also be used. As a method for producing such a polycarbonate resin, a known method can be employed. For example, a method in which a carbonate precursor such as phosgene is directly reacted with a dihydric phenol (interfacial polymerization method), a dihydric phenol and diphenyl carbonate, or the like. For example, a method (solution method) in which a transesterification reaction with a carbonate precursor such as the above is carried out.

  Examples of the divalent phenol for forming the polycarbonate resin as the component (A) include hydroquinone, resorcin, dihydroxydiphenyl, bis (hydroxyphenyl) alkane, bis (hydroxyphenyl) cycloalkane, bis (hydroxyphenyl) sulfide, Bis (hydroxyphenyl) ether, bis (hydroxyphenyl) ketone, bis (hydroxyphenyl) sulfone, bis (hydroxyphenyl) sulfoxide, bis (hydroxyphenyl) benzene, and nuclei substituted with alkyl groups or halogen atoms Derivatives and the like can be used. Representative examples of particularly suitable dihydric phenols include 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane, 2, 2-bis {(3,5-dibromo-4-hydroxy) phenyl} propane, 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 4,4'-dihydroxydiphenylsulfone, bis {(3,5-dimethyl-4-hydroxy) phenyl} sulfone, etc. Alternatively, two or more kinds can be used in combination. Among these, it is particularly preferable to use bisphenol A.

  Examples of the carbonate precursor for forming the polycarbonate resin as the component (A) include diaryl carbonates such as diphenyl carbonate, ditoluyl carbonate and bis (chlorophenyl) carbonate, dialkyl carbonates such as dimethyl carbonate and diethyl carbonate, and phosgene. Carbonyl halides, dihaloformates of dihydric phenols, and the like can be used, but are not limited thereto. Of these, diphenyl carbonate is preferred. These carbonate precursors can also be used alone or in combination of two or more.

  As the polycarbonate resin, for example, 1,1,1-tris (4-hydroxyphenyl) ethane or 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane, which is a trifunctional or higher polyfunctional It may be a branched polycarbonate resin copolymerized with an aromatic compound or a polyester carbonate resin copolymerized with an aromatic or aliphatic bifunctional carboxylic acid. The polycarbonate resin may be a mixture obtained by mixing two or more kinds.

The polycarbonate resin as the component (A) preferably has a molecular weight of 10,000 to 40,000, more preferably 12,000 to 35,000 in terms of viscosity average molecular weight.
The viscosity average molecular weight of the polycarbonate resin is measured using “CBM-20Alite system” and “GPC software” (manufactured by Shimadzu Corporation).

The polycarbonate resin as the component (A) preferably has a glass transition temperature of 120 to 290 ° C, more preferably 140 to 270 ° C.
The glass transition temperature of the polycarbonate resin is measured in the same manner except that the measurement sample is changed to the polycarbonate resin in the above-described method for measuring the glass transition temperature of the thermoplastic polyester resin.

  (A) It is preferable that content of the polycarbonate resin as a component is 10-80 mass% with respect to the resin composition whole quantity, More preferably, it is 30-80 mass%.

  In the case where a thermoplastic polyester resin and a polycarbonate resin are used in combination as the component (A), the mass ratio is (thermoplastic polyester resin: polycarbonate resin) = (9: 1) to (1: 9). Preferably there is.

〔Flame retardants〕
The flame retardant contained in the resin composition of the present invention (hereinafter also referred to as “component (B)”) is a component constituting the resin composition of the present invention. An organic flame retardant such as an acid ester compound can be used.
As the phosphoric acid ester compound, for example, phosphorous acid, phosphoric acid, phosphonous acid, and esterified products of phosphonic acid can be used.

  Specific examples of the phosphite ester include, for example, triphenyl phosphite, tris (nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, and the like.

  Specific examples of the phosphate ester include, for example, triphenyl phosphate (hereinafter also referred to as “TPP”), tris (nonylphenyl) phosphate, tris (2,4-di-t-butylphenyl) phosphate, distearyl penta Erythritol diphosphate, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphate, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphate, tributyl phosphate, bisphenol A bis -Diphenyl phosphate and the like.

  Specific examples of the phosphonous acid ester include, for example, tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylenephosphonite.

  Specific examples of the phosphonic acid ester include, for example, dimethyl benzenephosphonate, benzenephosphonic acid ester, and the like.

  As the phosphoric acid ester compound, an esterified product of phosphorous acid, phosphoric acid and phosphonic acid is preferable, and a phosphoric acid ester is particularly preferable.

  It is preferable that content of (B) component is 0.1-20 mass% with respect to the resin composition whole quantity, More preferably, it is 1-10 mass%.

In the resin composition of the present invention, in addition to the components (A) and (B), other resin components and optional components can be blended as necessary within the range in which the object of the present invention is achieved. . Examples of other resin components include polyethylene resin and ABS resin. Moreover, as an arbitrary component, for example, a crosslinking agent (for example, phenol resin), pigment, dye, reinforcing material (glass fiber, carbon fiber, talc, mica, clay mineral, potassium titanate fiber, etc.), filler (titanium oxide) , Metal powder, wood powder, rice husk, etc.), heat stabilizer, oxidative degradation inhibitor, UV absorber, lubricant, mold release agent, crystal nucleating agent (eg GMA-MA-PE), plasticizer, flame retardant, charging Examples thereof include an inhibitor and a foaming agent.
It is preferable that content of another resin component is 0.1-20 mass% with respect to the resin composition whole quantity, More preferably, it is 1-10 mass%. Moreover, it is preferable that content of an arbitrary component is 0.01-10 mass% with respect to the resin composition whole quantity, More preferably, it is 0.1-5 mass%.

〔viscosity〕
The resin composition of the present invention satisfies the following conditions (1) to (3). In the following, “HDT” indicates the deflection temperature under load of the resin composition.
Condition (1): The viscosity in the range of temperature (HDT-50 [° C.]) or more and (HDT [° C.]) or less is 10 ¹ (Pa · s) or more and less than 10 ⁶ (Pa · s).
Condition (2): The viscosity in the range of temperature (HDT + 150 [° C.]) or more and (HDT + 250 [° C.]) is 10 ⁻² (Pa · s) or more and less than 10 ¹ (Pa · s).
Condition (3): When the viscosity at HDT [° C.] is N1 (Pa · s) and the viscosity at (HDT + 150 [° C.]) is N2 (Pa · s), relational expression (1); 0 <N1-N2 <10 ⁴ must be satisfied.
When the resin composition of the present invention satisfies the above conditions (1) to (3), even when the regenerated polyester resin or polycarbonate resin is molded again by the injection molding method, the obtained molded product has a short shot. Occurrence of molding defects such as is suppressed.

The deflection temperature under load (HDT) of the resin composition of the present invention is preferably 50 to 200 ° C, more preferably 60 to 190 ° C.
The deflection temperature under load (HDT) of this resin composition is measured in accordance with “JIS K7207”. Specifically, a length of 130 mm, a width of 13 mm, and a thickness of a pellet-like sample are measured by an injection molding method. A test piece of 6.5 mm is produced, and the test piece is obtained by measuring the thermal deformation temperature under a load of 4.6 kgf / cm ² .

The viscosity of the resin composition of the present invention is measured under the following measurement conditions using a viscoelasticity measurement system “ARES” (manufactured by Rheometric Science).
-Measurement conditions-
・ Distortion: 10%
・ Temperature: 300-50 ° C. (Cooling rate: 5 ° C./min)
・ Frequency: 10 rad / s
・ Gap: 1.5mm
・ Plate type: Parallel plate (diameter: 25mm)

  The viscosity of the resin composition of the present invention is adjusted by adjusting (I) the melting / kneading conditions in the melting / kneading treatment, (II) the gap passing treatment conditions in the gap passing treatment, etc. in the resin composition production method described later. Can be controlled.

[Method for producing resin composition]
The method for producing the resin composition of the present invention is not particularly limited, but a polymer mixture comprising at least (A) component and (B) component is (I) melted and kneaded to obtain a molten polymer kneaded product obtained. It is preferable that the product is obtained by passing through a gap passing treatment (II) described later, and then subjecting the polymer kneaded product to (III) cooling treatment. The resin composition thus obtained is made into a pellet by cutting with a pelletizer, for example, in order to facilitate the processing at the time of injection molding by the injection molding method.

(I) Melting / kneading treatment The melting / kneading treatment is performed, for example, by using an extruder. Such an extrusion kneader is not particularly limited, and a known extrusion kneader using a shearing force can be used. For example, a twin screw extrusion kneader “KTX30” (manufactured by Kobe Steel), “KTX46” ( Kobe Steel Corporation).
Melting / kneading conditions are not particularly limited. For example, the screw rotation speed is 50 to 1000 rpm, and the melting / kneading temperature is 150 to 500 ° C., for example.
The viscosity in the resin composition of the present invention can be controlled by appropriately adjusting the melting and kneading conditions.

(II) Gap passing treatment The gap passing treatment is performed by passing the molten polymer kneaded material through a slit having a gap distance of less than 5 mm after melting and kneading treatment.
The resin composition of the present invention is obtained through a gap passing treatment in which a gap distance is passed through a slit having a length of less than 5 mm, whereby the mechanical strength of the resin composition is improved.

In the resin composition of this invention, it is preferable that the said clearance passage process is obtained through 1 time or more, Preferably it is 2 times or more, More preferably, it passes 3 times or more.
The mechanical strength of the resin composition is remarkably improved as the number of gap passing treatments is increased. The upper limit of the number of times of the gap passing process is usually 1000 times. It is possible to reduce the number of times the gap passing process is performed after kneading with a single-screw or twin-screw kneader, for example, when the gap passing process is continuously performed with a device attached to the discharge port of the twin-screw kneader. Can reduce the number of times from 3 to 10 times.

The gap distance of the slit is less than 5 mm, preferably 1 to 3 mm. For example, in the case of using an apparatus having two or more slits, the gap distances are each independently less than 5 mm, and more preferably each is independently 1 to 3 mm.
When the gap distance of the slit is 5 mm or more, there is a possibility that high mechanical strength cannot be obtained in the resin composition.

  Hereinafter, as a specific example of the gap passing process, a method using an apparatus having two slits with a gap distance of less than 5 mm in series will be described.

FIG. 1 is an explanatory view showing one structural example of an apparatus (die) used for a gap passing process for obtaining the resin composition of the present invention, wherein (a) is a perspective plan view, and (b) is PQ. It is line sectional drawing.
This apparatus 10A includes a substantially rectangular parallelepiped housing, and includes an inflow port 5 for allowing an object to be processed to flow in and an outlet port 6 for discharging a processed object, and between the inflow port 5 and the discharge port 6. In the flow path of the object to be processed, two slits (2a, 2b) formed between two parallel planes are provided in series.
Immediately before each of the slits 2a and 2b, there are reservoir portions 1a and 1b having a cross-sectional area larger than that of the slits 2a and 2b.

  This device 10A uses the pushing force of the extrusion kneader as a driving force for moving the molten polymer kneaded material by connecting the inlet 5 to the discharge port of an extrusion kneader (not shown), The polymer kneaded material as a whole can be moved in the movement direction MD and can pass through the slits 2a and 2b. Thus, since apparatus 10A can be used by being connected to the discharge port of an extrusion kneader, it can also be called a die.

  The polymer kneaded material flows from the inflow port 5 into the pool portion 1a and spreads in the width direction WD. The polymer kneaded material filled in the reservoir 1a passes through the slit 2a and moves to the reservoir 1b, and then passes through the slit 2b and is discharged from the discharge port 6.

Gap distance x ₁ in the slit 2a is specifically a 3 mm, the gap distance x ₂ in the slit 2b is specifically a 3 mm.

In general, the distances y ₁ and y ₂ in the movement direction MD in the slits 2a and 2b are preferably independently 2 to 200 mm, more preferably 5 to 50 mm.
The distance y ₁ in the movement direction MD in the slit 2a is specifically 50 mm, and the distance y ₂ in the movement direction MD in the slit 2b is specifically 40 mm.

The distance z ₁ in the width direction WD in the slits 2a and 2b is usually preferably 10 to 500 mm, more preferably 50 to 300 mm, and specifically 250 mm.

In general, the maximum heights h ₁ and h ₂ in the pool portions 1a and 1b are preferably 3 to 150 mm, more preferably 5 to 100 mm, and specifically 50 mm.
In the present invention, the maximum height of the reservoir portion refers to the maximum height in a vertical section with respect to the width direction WD.

The distance m ₁ in the movement direction MD in the pool part 1a and the distance m ₂ in the movement direction MD in the pool part 1b may be 1 mm or more independently, preferably 2 mm or more, more preferably 5 mm from the viewpoint of efficiency. More preferably, it is 10 mm or more, specifically 100 mm. The upper limit of the distance m ₁ and m _2, is not particularly limited, the distance m ₁ and when m ₂ is too large, an extrusion kneading machine efficiency is connected to the inlet 5 with reduced It is necessary to increase the pushing force. Accordingly, the distances m ₁ and m ₂ are each preferably preferably 1 to 300 mm, more preferably 2 to 100 mm, and still more preferably 5 to 50 mm.

Sectional area S _2a of the slit 2a and the cross-sectional area S _2b of the ratio S _1a / S _2a and the slit 2b of the maximum cross-sectional area S _1a of the immediately preceding reservoir 1a and the maximum cross-sectional area S _1b of the immediately preceding reservoir 1b The ratio S _1b / S _2b is usually independently 1.1 or more, particularly 1.1 to 1000. From the viewpoint of more uniform mixing / dispersion, downsizing of the apparatus, and prevention of vent-up, 2 -100 is preferable, More preferably, it is 3-15.

The flow rate when the polymer kneaded material passes through the slit may be 1 g / min or more, preferably 10 to 5000 g / min, more preferably 10 to 500 g / min, as a value per 1 cm ² of the sectional area of the slit. is there.

In the present invention, the cross-sectional area means an area in a vertical cross section with respect to the moving direction MD.
In the present invention, the flow rate is measured by dividing the discharge amount (g / min) of the polymer kneaded material discharged from the discharge port by the cross-sectional area (cm ² ) of the gap.

The viscosity of the polymer kneaded product during the gap passing treatment is not particularly limited as long as the flow velocity during the gap passing is achieved, but is, for example, 1 to 10000 Pa · s, preferably 10 to 8000 Pa · s.
The viscosity of the polymer kneaded material is measured by a viscoelasticity measuring device “MARS” (manufactured by Harker).

  The pressure for moving the polymer kneaded material in the movement direction MD is not particularly limited as long as the flow velocity at the time of passing through the gap is achieved, but is preferably 0.1 MPa or more as the resin pressure indicated by the differential pressure from the atmospheric pressure. . The resin pressure is the pressure of the polymer kneaded material measured 1 mm or more inside from the resin discharge port in the slit, and is measured by directly measuring with a pressure gauge. The higher the pressure, the more effective, but if the resin pressure is too high, significant shearing heat is generated and the polymer may be decomposed. Therefore, the resin pressure is preferably 500 MPa or less, more preferably 50 MPa or less.

The temperature of the polymer kneaded product during the gap passing treatment is not particularly limited as long as the flow velocity during the gap passing is achieved, but is preferably 400 ° C. or lower because the polymer is decomposed at a high temperature exceeding 400 ° C. Further, the temperature of the polymer kneaded product during the gap passing treatment is preferably a temperature equal to or higher than the glass transition temperature (Tg) of the polymer because the resin pressure does not increase remarkably.
The temperature of the polymer kneaded product during the gap passing process can be controlled by adjusting the heating temperature of the apparatus for performing the process.
The viscosity of the resin composition of the present invention can be controlled by appropriately adjusting the temperature of the polymer kneaded product during the gap passing treatment.

(III) Cooling treatment The cooling treatment is not particularly limited, for example, a method of immersing the polymer kneaded material subjected to the gap passing treatment in water of 0 to 60 ° C, a method of cooling with a gas of -40 ° C to 60 ° C, It is performed by a method of contacting with a metal at -40 ° C to 60 ° C. Further, for example, the polymer kneaded material subjected to the gap passing treatment may be left as it is and cooled.

  The resin composition thus obtained is usually cut by a pelletizer in order to facilitate processing during injection molding by the injection molding method.

In order to obtain the resin composition of the present invention, a premixing process in which all components constituting the polymer mixture are mixed in advance may be performed prior to (I) the melting and kneading process.
In addition, after the premixing treatment, it is preferable to sufficiently dry the polymer mixture from the viewpoint of suppressing the hydrolysis reaction of the thermoplastic polyester resin before the (I) melting / kneading treatment.

  The production method for obtaining the resin composition of the present invention is not limited to the above embodiment, and various modifications can be made.

  According to the resin composition of the present invention, when the resin composition contains a flame retardant and has a specific viscosity, the recycled polyester resin or polycarbonate resin is molded again by an injection molding method. However, in the obtained molded product, occurrence of molding defects such as short shots is suppressed, and excellent flame retardancy is obtained.

  Hereinafter, specific examples of the present invention will be described, but the present invention is not limited thereto.

[Production Example 1 of Resin Composition]
The components shown in Table 1 were dry blended at a predetermined mass ratio using a V-type mixer, and the mixture was dried at 60 ° C. for 4 hours under reduced pressure using a vacuum dryer, and premixed. The dried mixture was charged from the raw material supply port of a twin-screw extrusion kneader “KTX30” (manufactured by Kobe Steel) and melted under the conditions of discharge rate: 30 kg / hour, resin pressure: 4 MPa, screw rotation speed: 250 rpm. A kneading process was performed. In this twin-screw extrusion kneader, the cylinder part is composed of nine blocks C1 to C9 for each temperature control block, the raw material supply port is provided in the C1 part, and the rotor and kneader are provided in the C3 part and the C7 part. A combination of screws is arranged, and a vent is installed at C8 part. Then, using the apparatus (die) having the configuration shown in FIG. 1, the polymer kneaded material in a molten state discharged from the twin-screw extrusion kneader is flown from the inlet (5) under the following gap passage processing conditions, Were passed through the slits (2a, 2b) and discharged from the discharge port (6) to perform a gap passing process. The polymer kneaded material discharged from the die was cooled by immersing it in water at 30 ° C., and was cut with a pelletizer to obtain a pellet-shaped resin composition [1].

-Gap passage processing conditions-
Slit gap distance: 3mm
Flow rate of polymer kneaded material: 20 kg / h
Resin pressure of polymer kneaded material: 8 MPa
Temperature of polymer kneaded material: 270 ° C

[Production Examples 2 to 12 of resin composition]
Other than having changed the kind of each component which comprises a resin composition, its content, and the screw rotation speed conditions in a melt-kneading process, and the temperature conditions of the polymer kneaded material in a clearance passage process according to what is shown in Table 1 Obtained resin compositions [2] to [12] in the same manner as in Production Example 1 of the resin composition.

In Table 1, “PET” in the component (A) is obtained from a PET bottle that has been used and discarded (inherent viscosity: 0.90 dl / g, melting point: 270 ° C., glass transition temperature: 76 ° C. “PEN” is “Teonex” (manufactured by Teijin Chemicals Limited) (melting point: 275 ° C., glass transition temperature: 118 ° C.), and “polycarbonate resin” is an optical disc that has been used and discarded. (Viscosity average molecular weight: about 15000, glass transition temperature: 148 ° C.).
“TPP” in the component (B) is “triphenyl phosphate” (manufactured by Daihachi Chemical Industry Co., Ltd.).
“Polyethylene resin” in other resin components is “Hi-Zex” (manufactured by Prime Polymer Co., Ltd.) “Phenolic resin” as a crosslinking agent in other optional components is “Sumilite resin” (manufactured by Sumitomo Bakelite Co., Ltd.), and “GMA-MA-PE” as a crystal nucleating agent is “bond first” (Sumitomo). Made by Chemical Co., Ltd.).

[Examples 1-5 and Comparative Examples 1-7]
The following evaluations (1) to (3) were performed using the obtained pellet-shaped resin compositions [1] to [12].

(1) Releasability After the resin compositions [1] to [12] are dried at 80 ° C. for 4 hours, a flat plate of 120 mm × 120 mm × 3 mm is used using an injection molding machine “J55ELII” (manufactured by Nippon Steel Works). The mold release property at the 10th shot was evaluated according to the following evaluation criteria. The conditions were a cylinder temperature of 280 ° C., a mold temperature of 40 ° C., and an injection pressure of 40 MPa. The results are shown in Table 2.
A: The occurrence of poor mold releasability is not observed in any of the 10 molded products.
B: Occurrence of defective releasability is observed in only one of the 10 molded products.
C: Out of 10 molded products, the occurrence of defective releasability is observed in 2 or more and 9 or less.
D: The occurrence of defective releasability is observed in all 10 molded products.

(2) Fluidity After the resin compositions [1] to [12] were dried at 80 ° C. for 4 hours, an injection molding machine “J55ELII” (manufactured by Nippon Steel Works) was used, and a rod flow test piece (channel thickness) The flow length was evaluated according to the following evaluation criteria at a thickness of 1 mm and a channel width of 8 mm. The conditions were a cylinder temperature of 280 ° C., a mold temperature of 40 ° C., and an injection pressure of 40 MPa. The greater the flow length, the better the fluidity and the lower the incidence of short shots. The results are shown in Table 2.
A: 100 mm or more B: 60 mm or more and less than 100 mm C: 20 mm or more and less than 60 mm (no problem in practical use)
D: less than 20 mm (practical problem)

(3) Charpy impact strength After the resin compositions [1] to [12] were dried at 80 ° C. for 4 hours, the cylinder set temperature was 280 ° C. using an injection molding machine “J55ELII” (manufactured by Nippon Steel). A 100 mm × 10 mm × 4 mm strip test piece was molded at a mold temperature of 40 ° C., a Charpy impact test (U notch, R = 1 mm) was performed in accordance with “JIS-K7111,” and evaluated according to the following evaluation criteria. . The results are shown in Table 2.
A: 42 kJ / m ² or more B: 32 kJ / m ² or more and less than 42 kJ / m ² C: 6 kJ / m ² or more and less than 32 kJ / m ² (no problem in practical use)
D: Less than 6 kJ / m ² (practical problem)

  FIG. 2 shows a graph of viscosity curves in the resin composition [1] according to Example 1 and the resin composition [10] according to Comparative Example 5.

1a, 1b Reservoir 2a, 2b Slit 5 Inlet 6 Discharge 10A Device (die)

Claims (2)

A resin composition for injection molding containing a thermoplastic polyester resin and / or a polycarbonate resin and a flame retardant,
A resin composition characterized by satisfying the following conditions (1) to (3).
Condition (1): Viscosity in the range of temperature (HDT-50 [° C.]) or more and (HDT [° C.]) or less is 10 ¹ (Pa · s) or more and less than 10 ⁶ (Pa · s) (provided that “HDT” indicates the deflection temperature under load of the resin composition.
Condition (2): The viscosity in the range of temperature (HDT + 150 [° C.]) or more and (HDT + 250 [° C.]) is 10 ⁻² (Pa · s) or more and less than 10 ¹ (Pa · s).
Condition (3): When the viscosity at HDT [° C.] is N1 (Pa · s) and the viscosity at (HDT + 150 [° C.]) is N2 (Pa · s), relational expression (1); 0 <N1-N2 <10 ⁴ must be satisfied.   It is obtained through a gap passing treatment in which a molten polymer kneaded material containing a thermoplastic polyester resin and / or a polycarbonate resin and a flame retardant is passed through a slit having a gap distance of less than 5 mm. The resin composition according to claim 1.