JPH05202182A - Injection molding of polycarbonate copolymer - Google Patents

Abstract

PURPOSE:To obtain injection moldings improved in surface characteristics (e.g. lubricating properties or abrasion resistance) while keeping transparency and mechanical characteristics (e.g. flexural or tensile characteristics) of polycarbonate. CONSTITUTION:The objective polycarbonate copolymer injection moldings are injection moldings from a polycarbonate-polysiloxane copolymer having a structural unit consisting of a dihydric phenol and a polysiloxane and being 0.1-20wt.% in a ratio of unit from polysiloxane. In the injection moldings, a concentration of polysiloxane unit in a surface layer whose depth from molding surface is <50Angstrom is 2 or more times that of polysiloxane unit in a core layer whose depth is >=50Angstrom .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polycarbonate injection-molded article having improved lubricity and abrasion resistance, and more particularly, polycarbonate having a concentration of siloxane constituent units in the surface layer higher than that in the core layer. -Injection molded articles of polysiloxane copolymers.

[0002]

2. Description of the Related Art Generally, silicone oil is added or polysiloxane is blended for surface modification of polycarbonate such as slipperiness and abrasion resistance. However, when a small amount is added, surface modification is insufficient. When mixed in a large amount, the compatibility with polycarbonate is poor, so the molded product becomes cloudy and the mechanical properties (bending, pulling, etc.) deteriorate,
In addition, there are drawbacks such that the surface characteristics cannot be maintained due to wear and detachment for long-term use.

[0003]

The present invention has solved these problems. That is, the present invention is represented by the following general formula
Molding obtained by injection molding of a polycarbonate-polysiloxane copolymer having the structural units represented by (A) and (B) and the proportion of the structural unit represented by (B) being 0.1 to 20% by weight. Polycarbonate co-weight which is a product and whose concentration of the structural unit (B) in the surface layer having a depth of less than 50Å from the surface of the molded product is more than twice the concentration of the structural unit (B) in the core layer having a depth of 50Å or more. Combined injection molded product

[0004]

[Chemical 3]

(In the formula, R _{1 to} R ₈ each represent hydrogen, a halogen or an alkyl group or an aryl group which may have a substituent, and R ₉ and R ₁₀ each have a hydrogen, a halogen or a substituent. Optionally represents an alkyl group or an aryl group, X is

[0006]

[Chemical 4]

Wherein R ₁₁ and R ₁₂ each represent hydrogen, halogen or an alkyl or aryl group which may have a substituent, or R ₁₁ and R ₁₂ are bonded together to form a carbocycle. Alternatively, it represents a group forming a heterocycle, and a represents a positive number of 1 or more. ). The proportion of the structural unit represented by (B) is preferably 1 to 20% by weight, and the structural units (A) and (B) are preferably those which are randomly repeated.

The structure of the present invention will be described below. The polycarbonate resin used in the present invention includes a dihydric phenol represented by the following general formula (1) and a polysiloxane represented by the general formula (2).

[0009]

[Chemical 5]

(In the general formula (1), X and R _{1 to} R ₈ are represented by the general formula (A)
And n is an integer of 1 to 1000. General formula
In (2), R ₉ and R ₁₀ each represent hydrogen, halogen or an optionally substituted alkyl group or aryl group, and Y
Is halogen, -R ₁₃ OH, -R ₁₃ COOH, -R ₁₃ NH ₂ , -R ₁₃ NH ₂ ,
Represents --SH 2, R ₁₃ represents a linear, branched or cyclic alkylidene group, an aryl-substituted alkylidene group or an aryl group, R ₁₄ represents an alkyl, alkenyl, aryl or aralkyl group, and m represents 0 or 1. Is obtained by copolymerizing) with phosgene, a carbonic acid ester, or a chloroformate, and is a polycarbonate-polysiloxane copolymer in which the proportion of the constitutional unit represented by the general formula (B) is 0.1 to 20% by weight. It is a polymer. When the proportion of the structural unit represented by the general formula (B) exceeds 20% by weight, the transparency decreases.
The proportion of the structural unit represented by (B) is preferably 1.0% by weight or more, and if it is less than 1.0% by weight, a sufficient polysiloxane concentration cannot be obtained on the surface and the surface characteristics tend to deteriorate.
The viscosity average molecular weight of the copolymer is preferably 15,000 to 50,000. When the viscosity average molecular weight is less than 15,000, the strength of the molded product is not sufficient, and when it exceeds 50,000, the productivity tends to decrease.

The dihydric phenol represented by the general formula (1) used as a raw material for the co-polycarbonate resin of the present invention includes bis (4-hydroxyphenyl) methane and bis (4
-Hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) ketone, 1,1-bis (4
-Hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A; BPA), 2,2-
Bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) cyclohexane (bisphenol Z
BPZ), 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 2,2-bis (4-hydroxy) -3-Bromophenyl) propane, 2,2-bis (4-hydroxy-3-
Chlorophenyl) propane, 2,2-bis (4-hydroxy-
Examples include 3,5-dimethylphenyl) propane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, and bis (4-hydroxyphenyl) diphenylmethane. Among them, 2,2-bis (4-hydroxyphenyl) propane and 1,1-bis (4-hydroxyphenyl) cyclohexane are particularly preferable.

Illustrating the polysiloxane of the general formula (2), for example,

[0013]

[Chemical 6]

(In the general formulas (3) to (9), R ₉ and R ₁₀ are each hydrogen, a halogen or an alkyl group which may have a substituent or an aryl group, which is the same as in the general formula (1). Indicates R ₁₄
Represents an alkyl, alkenyl, aryl, or aralkyl group, similar to Y in the general formula (2), n represents an integer of 1 to 1000, and b represents a positive integer. ), Etc. Among them, α, ω-bis [3- (o-hydroxyphenyl)
Propyl] Polydimethylsiloxane is particularly preferred.

The dihydric phenol represented by the general formula (2) is a phenol having an olefinically unsaturated carbon-carbon bond, preferably vinylphenol, allylphenol or isopropenylphenol, having a predetermined polymerization degree n. It can be easily produced by subjecting the terminal of a polysiloxane chain having a to a silanization reaction.

In the production of polycarbonate resin, a terminal stopper or a molecular weight modifier is usually used.
Examples of the terminal terminator include compounds having a monovalent phenolic hydroxyl group, and in addition to ordinary phenol, p-tertiary butylphenol, tribromophenol, etc., long-chain alkylphenol, aliphatic carboxylic acid chloride, and aliphatic carboxylic acid. , Hydroxybenzoic acid alkyl ester, hydroxyphenyl alkyl acid ester, alkyl ether phenol and the like. The amount used is 100 to 100 mol for all dihydric phenol compounds used.
The amount is 0.5 mol, preferably 50 to 2 mol, and it is naturally possible to use two or more compounds in combination. Further, a branching agent is added to the above dihydric phenol compound in an amount of 0.01
~ 3 mol%, especially 0.1-1.0 mol% can be used in combination to form a branched polycarbonate, and as the branching agent, phloroglysin, 2,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) can be used. ) Heptene-3,4,6-dimethyl-2,4,6-tri (4-
Hydroxyphenyl) heptene-2,1,3,5-tri (2-hydroxyphenyl) benzol, 1,1,1-tri (4-hydroxyphenyl) ethane, 2,6-bis (2-hydroxy-5-methyl) Benzyl) -4-methylphenol, polyhydroxy compounds exemplified by α, α ′, α ″ -tri (4-hydroxyphenyl) -1,3,5-triisopropylbenzene, and 3,
3-bis (4-hydroxyaryl) oxindole (=
Isatin bisphenol), 5-chloroisatin, 5,7-dichlorisatin, 5-bromoisatin and the like.

If desired, the polycarbonate resin used in the present invention may be blended with various additives known in the prior art, such as a reinforcing material, a filler, a stabilizer, an ultraviolet absorber, and the like. Examples include antistatic agents, lubricants, release agents, dyes, pigments, other flame retardants, and elastomers for improving impact resistance.

The injection-molded article in the present invention is molded by general injection molding. When the PC-polysiloxane copolymer is discharged, the injection molding method that involves shearing causes the transfer of polysiloxane to the surface, resulting in siloxane concentration on the extreme surface. The shear rate is 5 × 10 ³ to 5 × 10 ⁶ (1 / se
c) is preferred. If it is less than 5 × 10 ³ (1 / sec), the siloxane concentration will be insufficient, and if it exceeds 5 × 10 ⁶ (1 / sec), the necessary fluidity will not be obtained, and injection will tend to be difficult. The resin temperature is preferably 250 to 340 ° C from the viewpoint of heat resistance and fluidity.

The thickness of the injection molded product is usually 0.4-10.0 μm.
Is preferred. If the thickness is less than 0.4 μm, the strength of the molded product will be insufficient, and if it exceeds 10 μm, the moldability will be poor. In the injection-molded product of the present invention, the concentration of the structural unit (B) in the surface layer having a depth of less than 50 Å from the surface of the molded product is at least twice the concentration of the structural unit (B) in the core layer having a depth of 50 Å or more. However, when the proportion of the structural unit (B) is 1 to 20% by weight, the concentration of the structural unit (B) in the surface layer is preferably in the range of 2 to 100% by weight.

The composition analysis of the surface layer depth of the polycarbonate-polysiloxane copolymer injection-molded article of the present invention having a depth of less than 50 Å was carried out by using C-using ESCALAB MK2 manufactured by VGScientific.
Quantitation was performed for 1S, O-1S, and Si-2P. The conditions are C, C = C, CH, C-Si derived peaks for C (carbon),
CO-derived peaks at 286.1-286.2eV, 290.5-290.7e
Peak derived from carbonate bond (OCOO) of V, 291.7 to 29
A shakeup satellite peak due to the π-π ^* transition in the 2.3 eV unsaturated bond was detected. Regarding O (oxygen), peaks derived from C = O 2 at 532.2 to 532.3 eV, Si-O, and peaks derived from CO at 533.9 to 534.0 eV were detected. For Si (silicon), 102 eV -O-Si (CH ₃ ) _2-
The peak derived from O- (siloxane) was detected. ESCA measurement depth depends on atomic and electron energies 1
Average free process is 20Å for C, O and Si at 00-600eV
It is below, and the detection of atoms at a depth of 50Å or more is rarely performed. Therefore, ESCA measures siloxane concentrations with a surface layer depth of less than 50Å. In the analysis of the core layer having a surface layer depth of 50 Å or more, a comparison was made by measuring the part where the surface of 50 Å was shaved by performing argon etching on the surface.

[0021]

【Example】

Example 1 In 580 liters of 8.8% (W / V) aqueous sodium hydroxide solution, 91.2 kg of bisphenol A (BPA) and the dihydric phenol of the general formula (3) (wherein R ₉ and R ₁₀ are methyl groups, n = 41, b = 3 ortho bond) 5.95 kg (set so that the structural formula (B) is 5% by weight) and 100 g of hydrosulfite were added and dissolved. To this, 360 liters of methylene chloride was added, and pt-butylphenol (PTBP) was added while stirring at 15 ° C.
1.44 kg was added and then 53.0 kg of phosgene was bubbled in over 60 minutes. After the completion of blowing, vigorously stir to emulsify the reaction solution.After emulsification, add 100 mL of triethylamine,
Polymerization was performed by stirring for about 1 hour. The polymerization solution was separated into an aqueous layer and an organic layer, the organic layer was neutralized with phosphoric acid, and the washing solution was repeatedly washed with water until the pH became neutral, and then 470 liters of isopropanol was added to precipitate the polymer. It was The precipitate was filtered and then dried to obtain a white powdery polycarbonate-polysiloxane copolymer (PC-Si) resin. The obtained PC-Si resin was injection-molded by Meiki Co., Ltd. with a nozzle diameter of 3 mm and a resin temperature of 300.
℃, screw rotation speed 50r.pm (screw diameter 45mm),
Injection speed 1.6 cm / sec, maximum injection pressure 1400 Kg / cm ² , holding pressure 10
00Kg / cm ² , 127mm length, 12.7m width under the condition of injection time 15sec
An injection-molded product with m and thickness of 3.2 mm was prepared. The shear rate at this time was 9.8 × 10 ³ (1 / sec), with an injection rate of 26 cc / sec.
Met. The shear rate was calculated from the following formula. rω.a (shear rate) = 4 Q / πR ³ Q = volumetric flow rate extruded from the capillary (cm ³ ) R = capillary radius (cm) The results are shown in Table 1.

The concentration (wt%) of siloxane in the surface layer having a depth of less than 50Å from the surface of the injection-molded article and the concentration (wt%) of siloxane in the core layer having a depth of 50Å or more are quantitatively determined using the ESCA described above. (C-1S, O-1S, Si-2P). For the randomness of the molded product, the presence or absence of fibrous non-uniformity was examined by TEM observation. The wear resistance of the molded product was measured by a Taber wear test (load 1 kg, CS-17 wheel, toluene atmosphere, 24 hr) in terms of wear amount mg.

Example 2 The same as Example 1 except that 107.2 kg of bisphenol Z (BPZ) was used instead of BPA. The results are also shown in Table 1.

Example 3 Structural formula (B) from the dihydric phenol of the general formula (3) (R ₉ and R ₁₀ are methyl groups respectively, n = 41, b = 3 and ortho bond)
Example 1 except that the concentration of 1 was set to 1% by weight.
Same as. The results are also shown in Table 1.

Example 4 Structural formula (B) from the dihydric phenol of the general formula (3) (R ₉ and R ₁₀ are methyl groups respectively, n = 41, b = 3 and ortho bond)
Example 1 except that the concentration of was adjusted to 20% by weight.
Same as. The results are also shown in Table 1.

Example 5 The same as Example 1 except that the dihydric phenol of the general formula (3) used was a methyl group for R ₉ and R ₁₀ , n = 41 and b = 2 and a para bond. I chose The results are also shown in Table 1.

Example 6 Same as Example 1 except that R ₉ and R ₁₀ were each a methyl group, n = 101 and b = 3, and ortho-bonded as the dihydric phenol of the general formula (3). I chose The results are also shown in Table 1.

Example 7 As the dihydric phenol represented by the general formula (3), R ₉ is a methyl group,
The same procedure as in Example 1 was carried out except that R ₁₀ was a phenyl group, n = 41, b = 3 and ortho-bonded. The results are also shown in Table 1.

Example 8 Example 1 was repeated except that the dihydric phenol represented by the general formula (4) was a dihydric phenol having a methyl group for R ₉ and R ₁₀ and n = 41. I did the same. The results are also shown in Table 1.

Comparative Example 1 The procedure of Example 1 was repeated except that no dihydric phenol containing the siloxane of the general formula (2) was used. The results are also shown in Table 1.

Comparative Example 2 The procedure of Example 2 was repeated except that the dihydric phenol containing the siloxane of the general formula (2) was not used at all. The results are also shown in Table 1.

Comparative Example 3 R ₉ and R ₁₀ are methyl groups, n = 41 and b = 3, and an ortho-bonded dihydric phenol represented by the general formula (3) is a structural unit in a copolymer.
Example 1 except that (B) was used in an amount of 0.09% by weight.
Same as. The results are also shown in Table 1.

Comparative Example 4 R ₉ and R ₁₀ are methyl groups, n = 41 and b = 3, and an ortho-bonded dihydric phenol represented by the general formula (3) is a structural unit in a copolymer.
Same as Example 1 except that (B) was used in an amount of 25% by weight. The results are also shown in Table 1.

Comparative Example 5 A dihydric phenol represented by the general formula (3), in which R ₉ and R ₁₀ are methyl groups, n = 41 and b = 3 and ortho linkages, is added to the polycarbonate of Comparative Example 1 and the structural formula (B) is used. Was blended so that the ratio of was 5% by weight. The results are also shown in Table 1.

[0035]Table 1 monomer ViscosityFilm characteristics Formula (A) No Formula (B) No AverageSiloxane concentration OrchidAbrasion resistance Phenol^{* 1} Siloxane^{* 2} Molecular weight Depth 50 Å Not dam Pencil Wear amount of full surface layersex hardness mg weight% weight% Siloxane concentration(weight%) Fruit 1 BPA 95.0 5.0 3.0 × 10^Four 14 ○ 2H 13 Actual 2 BPZ 95.0 5.0 3.3 × 10^Four 15 ○ 2H 13 Actual 3 BPA 99.0 1.0 3.0 × 10^Four 5 ○ H 18 Actual 4 BPA 80.0 20.0 3.2 × 10^Four 43 ○ 3H 10 Actual 5 BPA 95.0 5.0 3.0 × 10^Four 12 ○ 2H 14 Actual 6 BPA 95.0 5.0 3.0 × 10^Four 15 ○ 2H 15 Actual 7 BPA 95.0 5.0 3.3 × 10^Four 12 ○ 2H 17 Actual 8 BPA 95.0 5.0 3.0 × 10^Four 16 ○ 2H 14 ratio 1 BPA 100.0 − 0.0 3.0 × 10^Four − ○ HB 32 ratio 2 BPZ 100.0 − 0.0 3.2 × 10^Four − ○ H 23 ratio 3 BPA 99.91 0.09 3.0 × 10^Four 0.5 ○ H 26 ratio 4 BPA 75.0 25.0 3.4 × 10^Four 56 x 3H 10 Ratio 5 BPA 95.0 ^{* 3} 5.0 3.0 × 10 ⁴ 9 × H 25 ^{* 1} BPA: Bisphenol A, BPZ: Bisphenol Z^{* 2} : R_9,R_TenAre methyl groups; n = 41, b = 3 and one ortho bond
Polysiloxane of general formula (3): R_9,R_TenAre methyl groups; n = 41, b = 2 and general para-bonds
Polysiloxane of formula (3): R_9,R_TenAre methyl groups; n = 101, b = 3 and ortho-bonded general
Polysiloxane of formula (3): R₉Is a methyl group_,R_TenIs a phenyl group; an ortho-bonded polysiloxane of the general formula (3): n = 41, b = 3: R_9, R_TenAre methyl groups; n = 41 in the general formula (4)
Xanthane^{* 3} A blend of monomers.

[0036]

INDUSTRIAL APPLICABILITY The injection-molded product of the polycarbonate-polysiloxane copolymer of the present invention has an extremely surface (surface layer depth 50Å
(Less than) selectively collects polysiloxane segments,
Since it is more than double that of the core layer with a depth of 50Å or more, even a small amount of polysiloxane can be used to unexpectedly modify the surface of a polycarbonate injection molded product (improve lubricity, abrasion resistance, etc.). . Further, the injection-molded product of the polycarbonate-polysiloxane copolymer of the present invention is free from white turbidity and has good transparency as compared with the injection-molded product prepared from a mixture of a polycarbonate resin and polysiloxane having the same concentration of polysiloxane, and a polycarbonate. It has the advantage that its mechanical properties (bending, pulling, etc.) are maintained.

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[Procedure amendment]

[Submission date] January 30, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 2

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0019

[Correction method] Change

[Correction content]

The thickness of the injection molded product is usually preferably 0.4 to 10.0 mm. If the thickness is less than 0.4 mm, the strength of the molded product will be insufficient, and if it exceeds 10 mm, the moldability will be poor. In the injection-molded product of the present invention, the concentration of the structural unit (B) in the surface layer having a depth of less than 50Å from the surface of the molded product is at least twice the concentration of the structural unit (B) in the core layer having a depth of 50Å or more. However, when the proportion of the structural unit (B) is 1 to 20% by weight, the concentration of the structural unit (B) in the surface layer is preferably in the range of 2 to 100% by weight.

Claims (7)

[Claims] 1. A constitutional unit represented by the following general formulas (A) and (B), wherein the proportion of the constitutional unit represented by (B) is 0.
A molded product obtained by injection molding a polycarbonate-polysiloxane copolymer in an amount of 1 to 20% by weight, the structural unit (B) in the surface layer having a depth of less than 50Å from the surface of the molded product.
Units in the core layer with a concentration of 50 Å or more (B)
Polycarbonate copolymer injection-molded product having a concentration of at least twice that of (In the formula, R _{1 to} R ₈ each represent hydrogen, a halogen or an alkyl group or an aryl group which may have a substituent, and R ₉ ,
R ₁₀ represents hydrogen, halogen or an alkyl group or aryl group which may have a substituent. X is Wherein R ₁₁ and R ₁₂ each represent hydrogen, halogen or an alkyl group or aryl group which may have a substituent, or R ₁₁ and R ₁₂ are bonded together to form a carbocycle or heterocycle. And a represents a positive number of 1 or more. ) 2. The molded product according to claim 1, wherein the molded product has a thickness of 0.4 to 10.0 μm. 3. The proportion of the constituent unit (B) in the polycarbonate-polysiloxane copolymer is 1 to 20% by weight, and the concentration of the constituent unit (B) in the surface layer having a depth of less than 50Å is 2 to 100% by weight. The molded article according to claim 1, which is 4. The viscosity average molecular weight of the polycarbonate-polysiloxane copolymer is 15,000 to 50,000.
Molded product described 5. A structural unit (A) derived from a dihydric phenol selected from the group consisting of 2,2-bis (4-hydroxyphenyl) propane and 1,1-bis (4-hydroxyphenyl) cyclohexane. The molded article according to claim 1, which is 6. The structural unit (B) is α, ω-bis [3- (o-
2. A molded article according to claim 1, which is hydroxyphenyl) propyl] polydimethylsiloxane. 7. The molded article according to claim 1, wherein the polycarbonate-polysiloxane copolymer is a random copolymer.