KR101690835B1 - Diol monomer, its polycarbonate and article containing the same - Google Patents

Abstract

(상기 R₁, R₂, R₃, R₄, R₅ 및 R₆은 각각 수소 또는 탄소수 1~10의 알킬기이다)로 표시되는 화합물, 이를 포함하여 중합된 폴리카보네이트 및 물품에 관한 것이다.
본 기재에 따르면, 폴리카보네이트에 적용 시 분자량 감소 효과는 적으면서도 내열도 향상 효과가 큰 신규한 단량체와 이를 포함하고 경제적으로 제조될 수 있으며, 기계적 물성이 우수하면서도 내열성이 뛰어난 폴리카보네이트 및 물품을 제공하는 효과가 있다. The present disclosure relates to diol monomers, polycarbonates thereof, and articles containing them, and more particularly to diol monomers,
[Chemical Formula 1]

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms), polycarbonates and articles thereof polymerized therewith.
According to the present invention, there is provided a novel monomer having a small effect of decreasing the molecular weight when applied to polycarbonate and having a high heat resistance improving effect, and polycarbonate and article having excellent heat resistance, which can be produced economically and have excellent mechanical properties. .

Description

FIELD OF THE INVENTION [0001] The present invention relates to a diol monomer, a polycarbonate thereof, and an article containing the same. BACKGROUND ART [0002]

The present invention relates to a diol monomer, a polycarbonate thereof and an article containing the same, and more particularly to a novel monomer having a small effect of reducing molecular weight when applied to polycarbonate and having a high heat resistance improvement effect, Polycarbonate having excellent mechanical properties and excellent heat resistance, and articles containing the same.

The polycarbonate resin is produced by condensation polymerization of an aromatic diol such as bisphenol A and a carbonate precursor such as phosgene and has excellent impact strength, numerical stability, heat resistance, transparency, and the like. And so on.

In order to apply this polycarbonate resin to various fields in recent years, many attempts have been made to obtain desired physical properties by copolymerizing aromatic diols having two or more different structures and introducing monomers having different structures into the main chain of the polycarbonate.

Studies have been made to produce polycarbonate resins having particularly high heat resistance. However, when the heat resistance of the polycarbonate resin is improved, the mechanical properties and optical properties thereof are greatly deteriorated.

Korean Patent Publication No. 2007-0036091

In order to solve the problems of the prior art as described above, the present invention relates to a novel monomer having a small effect of decreasing molecular weight when applied to polycarbonate and having a high heat resistance improvement effect, and it can be economically produced, It is an object of the present invention to provide a polycarbonate excellent in heat resistance and an article including the polycarbonate.

These and other objects of the present disclosure can be achieved by all of the present invention described below.

In order to achieve the above object,

[Chemical Formula 1]

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms).

The present invention also provides a polycarbonate polymerized with a carbonate precursor and a diol monomer represented by the above formula (1).

The present disclosure also provides an article made from the polycarbonate.

As described above, according to the present invention, when a polycarbonate is applied to a polycarbonate, a novel monomer having a small effect of decreasing the molecular weight and having a high heat resistance improvement effect can be produced economically, and a poly It is effective to provide carbonates.

1 is a ¹ H NMR spectrum of the diol monomer prepared in Example 1. Fig.
2 is a ¹ H NMR spectrum of the diol monomer prepared in Example 2. Fig.

Hereinafter, the present invention will be described in detail.

The compounds of the present invention are represented by the following formula

[Chemical Formula 1]

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms).

As another example, each of R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ is hydrogen or an alkyl group having 1 to 3 carbon atoms. As another example, R ₂ , R ₃ and R ₄ are hydrogen, and R ₁ , R ₅ and R ₆ are alkyl groups having 1 to 10 carbon atoms or 1 to 3 carbon atoms. As another example, the R ₁ , R ₂ , R ₃ , R ₄ , R _5, and R ₆ may all be hydrogen. When applied to polycarbonate within the above range, the effect of reducing the molecular weight is small and the heat resistance is greatly increased.

The compound represented by Formula 1 may be, for example, a diol monomer used in the production of polycarbonate.

The compound represented by Formula 1 may be prepared by esterification of 4-hydroxybenzoic acid with a compound represented by Formula 2 under an acid or base catalyst.

(2)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms).

The polycarbonate of the present invention comprises a carbonate precursor,

[Chemical Formula 1]

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms).

The polycarbonate may be, for example, a polycarbonate polymerized by further including an aromatic diol monomer different from the diol monomer in the carbonate precursor and the diol monomer represented by the formula (1).

The monomer represented by Formula 1 may be, for example, 1 to 98% by weight, 5 to 50% by weight, or 10 to 40% by weight based on 100% by weight of the sum of the diol monomer and carbonate precursor.

The polycarbonate includes, for example, from 10% by weight to less than 100% by weight of the diol monomer represented by Formula 1, and from 0% by weight to 90% by weight of the aromatic diol monomer based on 100% by weight of the total amount of the diol monomer. Within this range, there is an effect of maintaining excellent mechanical properties and transparency inherent to polycarbonate and excellent heat resistance.

As another example, the polycarbonate is polymerized in an amount of more than 0 to 100% by weight of the diol monomer represented by the formula (1) and 0 to 100% by weight of the aromatic diol monomer based on 100% by weight of the total amount of the diol monomer , While maintaining the original mechanical properties and transparency of the polycarbonate within this range, it has an excellent heat resistance.

As another example, the polycarbonate may contain 1 to 60% by weight of the monomer represented by Formula 1, 25 to 85% by weight of the aromatic diol monomer, and 10 to 70% by weight of the carbonate precursor, based on 100% by weight of the sum of the diol monomer and carbonate precursor %. ≪ / RTI >

As another example, the polycarbonate may include 10 to 40% by weight of the monomer represented by Formula 1, 30 to 70% by weight of the aromatic diol monomer, and 20 to 60% by weight of the carbonate precursor based on 100% by weight of the sum of the diol monomer and carbonate precursor %. ≪ / RTI >

The carbonate precursor may be, for example,

[Chemical Formula 4]

(X ₁ and X ₂ are each independently a halogen, haloalkyl, halocycloalkyl, haloaryl, alkoxy or haloalkoxy group), and the effect of imparting the intrinsic properties of the polycarbonate within this range is have.

As another example, the carbonate precursor may be selected from the group consisting of dimethyl carbonate, diethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate, diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, di- And may be at least one member selected from the group consisting of carbonate, bis (diphenyl) carbonate, phosgene, triphosgene, diphosgene, bromophosgene and bishaloformate, preferably triphosgene or phosgene, And the like.

The carbonate precursor is, for example, 1 to 98% by weight, 5 to 50% by weight, or 10 to 40% by weight based on 100% by weight of the total amount of the diol monomer and carbonate precursor. Within this range, the carbonate polycarbonate precursor have.

Examples of the aromatic diol monomer include bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) ether, bis (4- hydroxyphenyl) sulfone, bis Bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) ketone, 1,1- Bis (4-hydroxyphenyl) cyclohexane (bisphenol Z), 2,2-bis (4-hydroxyphenyl) butane, 1,1- Propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy- Bis (3-hydroxyphenyl) propyl] polydimethylsiloxane is used as a catalyst for the polymerization of the polyfunctional (meth) acrylate monomer, 1-bis (4-hydroxyphenyl) It may be at least one member selected from the group true luer, preferably from bisphenol A, in which case the effect of increasing the fluidity of the polycarbonate.

The aromatic diol monomer is, for example, 1 to 98% by weight, 30 to 95% by weight, or 40 to 90% by weight based on 100% by weight of the total amount of the diol comonomer and the carbonate precursor. Within this range, the essential characteristics of the polycarbonate It is effective.

The polycarbonate may be polymerized by further including a molecular weight modifier.

The molecular weight regulator is, for example, mono-alkylphenol.

Examples of the mono-alkylphenol include p-tert-butylphenol, p-cumylphenol, decylphenol, dodecylphenol, tetradecylphenol, hexadecylphenol, octadecylphenol, eicosylphenol, docosylphenol and triacontyl Phenol, and is preferably para-tert-butylphenol. In this case, the effect of controlling the molecular weight is large.

The molecular weight modifier may be included in an amount of 0.1 to 10 parts by weight, 0.3 to 6 parts by weight, or 0.5 to 5 parts by weight based on 100 parts by weight of the total amount of the diol monomer. Within this range, a target molecular weight can be obtained.

The polycarbonate may have a glass transition temperature of 140 to 250 ° C, 145 to 237 ° C, or 150 to 200 ° C and a weight average molecular weight of 10,000 to 100,000 g / mol, 12,000 to 80,000 g / mol, or 14,000 to 70,000 g / mol. Within this range, the heat resistance of the polycarbonate is increased while maintaining the mechanical properties and optical properties inherent in the polycarbonate.

The polycarbonate may have, for example, a heat resistance (HDT) of 120 to 230 ° C, 130 to 230 ° C, or 135 to 200 ° C, and an excellent balance of physical properties within this range.

The polycarbonate is, for example,

(3)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms, n is 0 to 445, and m is 1 to 225) Carbonate.

As another example, n is an integer of 10 to 90, or an integer of 25 to 75, and m is an integer of 10 to 90, or an integer of 25 to 75, for example. Within this range, the mechanical properties, All of these have excellent effects.

The article of the present invention is characterized by containing the above polycarbonate.

The polycarbonate of the present invention can be, for example, an interfacial polymerization method. In this case, the polycarbonate can be polymerized at a low temperature under atmospheric pressure, and the molecular weight can be easily controlled.

The interfacial polymerization method may be, for example, a method of reacting a diol monomer, a carbonate precursor and a molecular weight modifier in the presence of an acid binder and an organic solvent.

The interfacial polymerization method may include, for example, pre-polymerizing, then adding a coupling agent, and then polymerizing again. In this case, a high molecular weight polycarbonate resin can be obtained.

The other materials used in the interfacial polymerization are not particularly limited as far as they can be used for polymerization of polycarbonate, and the amount thereof can also be adjusted as needed.

The acid binding agent is, for example, an alkali metal hydroxide such as sodium hydroxide, potassium hydroxide or the like or an amine compound such as pyridine.

The organic solvent is not particularly limited as long as it is a solvent used for polymerization of polycarbonate. For example, halogenated hydrocarbons such as methylene chloride and chlorobenzene may be used.

The interfacial polymerization may be carried out, for example, in the presence of a tertiary amine compound such as triethylamine, tetra-n-butylammonium bromide or tetra-n-butylphosphonium bromide, a quaternary ammonium compound or a quaternary phosphonium compound Further promoters may be used.

The reaction temperature of the interfacial polymerization is, for example, 0 to 40 ° C, and the reaction time is 10 minutes to 5 hours, for example. The pH during the reaction may be maintained at 9 or more or 11 or more.

The molecular weight regulator may be added before the initiation of polymerization, during the initiation of polymerization or after initiation of polymerization, for example.

The molded article of the present invention is characterized by containing the polycarbonate.

The molded article may be, for example, an injection molded article.

The molded article may further include at least one selected from the group consisting of an antioxidant, a heat stabilizer, a photostabilizer, a plasticizer, an antistatic agent, a nucleating agent, a flame retardant, a lubricant, an impact modifier, a fluorescent whitening agent, .

The molded product can be produced, for example, by mixing the polycarbonate resin and additives such as an antioxidant of the present invention well using a mixer, extruding the mixture into an extruder to prepare pellets, drying the pellets well And injecting the mixture into an injection molding machine.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention within the scope and spirit of the following claims, Such variations and modifications are intended to be within the scope of the appended claims.

[Example]

Example 1

≪ Preparation of diol monomer corresponding to formula (1) >

(1) Preparation of 4-acetoxybenzoyl chloride

80 g of 4-acetoxybenzoic acid was diluted with 2.2 equivalents of methylene chloride (MC) solvent to make a cloudy solution, and 1 to 3 drops of dimethylformamide was added thereto as a catalyst, followed by stirring at room temperature. At the same time as stirring, 58.92 g of oxalyl chloride was added slowly at room temperature, and 2.3 equivalents of the mixture were stirred for 1 to 2 hours. The remaining oxalyl chloride and methylene chloride solvent were removed through a rotary evaporator to obtain 88.1 g of liquid 4-acetone benzoyl chloride.

(2) Preparation of 4- (1- {4 - [(4-acetoxybenzoyl) oxy] phenyl} cyclohexyl) phenyl 4-acetoxybenzoate

54 g of commercially available BPZ (Bisphenol Z), 1 equivalent of 159 g of pyridine was diluted with 10 equivalents of stirring at room temperature. Thereafter, 88.1 g of the synthesized 4-acetoxybenzoyl chloride, 2.2 equivalents, was added slowly and the mixture was refluxed and stirred at 110 ° C for 3 to 4 hours. After confirming the disappearance of BPZ through thin plate chromatography (TLC), water was added to terminate the reaction. The organic layer was separated by extraction with ethyl acetate, 1N hydrochloric acid and distilled water, and residual water remaining in the organic layer was removed through magnesium sulfate, and the organic layer was removed by filtration. The solvent was removed from the obtained organic layer using a rotary evaporator. The solvent-removed material was recrystallized from ethyl acetate and methanol to give 4- (1- {4- [(4-acetoxybenzoyl) oxy] phenyl} cyclohexyl) phenyl 4-acetoxybenzoate as a white solid The obtained 4- (1- {4 - [(4-acetoxybenzoyl) oxy] phenyl} cyclohexyl) phenyl 4-acetoxybenzoate was confirmed by ¹ H NMR .

(3) Preparation of 4- (1- {4 - [(4-hydroxybenzoyl) oxy] phenyl} cyclohexyl) phenyl 4-hydroxybenzoate (HB-BPZ)

106.77 g of 4,4'-cyclohexylidene bisphenol bis (4-acetoxybenzoate) synthesized as described above was stirred in an ethanol solvent to prepare a mixed solution, and sodium methoxide diluted in a 25% methanol solvent ≪ / RTI > and 2.1 eq. Was added slowly at 0 < 0 > C. After stirring for 10 to 20 minutes, presence or absence of the reaction was confirmed by thin plate chromatography (TLC). When it was judged that the reaction was completed, 36.8 g of 35% aqueous hydrochloric acid solution was added at 0 ° C to obtain 4- Phenyl} cyclohexyl) phenyl 4-hydroxybenzoate, that is, the compound corresponding to the formula (1) was obtained in a yield of 91%, 98%, and the obtained 4- ( 1- {4 - [(4-Hydroxybenzoyl) oxy] phenyl} cyclohexyl) phenyl 4-hydroxybenzoate was confirmed by ¹ H NMR. (4H, m), 6.992 ppm (4H, m), and 7.147 ppm (4H, m) as the peak of ¹ H NMR (500 MHz, CDCl 2) ⑤ 7.389 ppm (4H, m), ⑥ 7.959 ppm (4H, m), and ⑦ 10.493 ppm (2H, s).

≪ Preparation of polycarbonate >

HB-BPZ (n = 1) was used to perform interfacial polymerization by triphosgene reaction with bisphenol A to prepare a high heat resistant polycarbonate copolymer.

Specifically, 230 g of H ₂ O, 23 g of BPA (bisphenol A), 7 g of HB-BPZ (10 mol) corresponding to the formula (1) were added to a 500 ml main reactor equipped with a nitrogen purge and a condenser and maintained at room temperature with a circulator 0.6 g of PTBP (p-tert-butylphenol), 50 g of NaOH and 114 g of MeCl ₂ were added and stirred for about 10 to 20 minutes.

16 g of triphosgene and 114 g of MeCl ₂ were added to a 250 ml round bottom flask and triphosgene was dissolved. The dissolved triphosgene solution was slowly added to the main reactor in which the BPA solution was dissolved. After the addition, triethylamine (TEA) 6 g (5 wt% in MC) was added thereto. The reaction pH was maintained at 11-13. The pH was dropped to 1 to 2 by the addition of HCl to terminate the reaction over time to allow sufficient reaction to take place. Then, stirring was stopped to separate the polymer layer and the water layer. Then, the water layer was removed, and pure H ₂ O was added again, and the water was washed 3 to 5 times. When the water was completely washed, only the polymer layer was extracted, and polymer crystals were obtained by reprecipitation using a non-solvent using methanol, acetone, n-hexane, H ₂ O, or the like. The obtained polycarbonate was measured for its molecular weight by GPC using a PC Standard, and it was confirmed that the weight average molecular weight was 54,000 g / mol.

≪ Preparation of injection specimen &

0.050 part by weight of tris (2,4-di-tert-butylphenyl) phosphite, and octadecyl-3- (3,5-di-tert- 0.030 part by weight of pentaerythritol tetrastearate and 0.030 part by weight of pentaerythritol tetra stearate were pelletized by using a twin-screw extruder with a vent of 30 mm in diameter. The pellets were molded into a cylinder temperature of 300 占 폚 and a mold temperature of 300 占 폚 using a JSW N-20C injection molding machine And injection molded at 90 ° C.

Example 2

Except that BPTMC (4,4 '- (3,3,5-trimethylcyclohexylidene) diphenol: Bisphenol TMC) was used in place of BPZ in Example 1, polycarbonate and An injection specimen thereof was prepared. The polycarbonate produced had a weight average molecular weight of 55,000 g / mol. The diol monomer (HB-BPTMC) corresponding to Formula 1 prepared here was confirmed by ¹ H NMR. The ¹ H NMR (500MHz, CDCl2) peak (δ) is ① 0.348ppm (3H, m), ② 0.954ppm (6H, m), ③ 1.034ppm (1H, m), ④ 1.047ppm (1H, m), (1H, m), (9H, m), (8H), (8H), (8H) m), 7.38 ppm (4H, m), 7.8915 ppm (4H, m), and 13.680 ppm (2H, s).

Example 3

Polycarbonate and its injection sample were prepared in the same manner as in Example 1 except that 20 mol% of HB-BPZ was used instead of 10 mol% of HB-BPZ in Example 1. The polycarbonate produced had a weight average molecular weight of 54,000 g / mol.

Example 4

Polycarbonate and its injection sample were prepared in the same manner as in Example 1, except that 30 mol% of HB-BPZ was used instead of 10 mol% of HB-BPZ in Example 1. The polycarbonate produced had a weight average molecular weight of 53,000 g / mol.

Comparative Example 1

Except that diol monomer corresponding to the formula 1 was not used and BPA (bisphenol A) was added in an amount corresponding to the amount of the diol monomer in the above Example 1 to obtain the polycarbonate and the injection specimen therefor . It was confirmed that the weight average molecular weight of the polycarbonate at this time was 50,000 g / mol.

[Test Example]

The properties of the polycarbonate injection specimens prepared in Examples 1 to 4 and Comparative Example 1 were measured by the following methods, and the results are shown in Table 1 below.

Impact strength: measured at 23 占 폚 according to ASTM D256 (1/8 inch, Notched Izod).

Transparency: Visually inspected, it was evaluated as transparent, translucent, and opaque.

* Weight average molecular weight (g / mol): Measured with a PC standard using an Agilent 1200 series.

* Flowability (MI): Measured according to ASTM D1238 (300 ° C, condition of 1.2 kg).

* Repeating unit: Measured by ¹ H-NMR using Varian 500 MHz.

* Glass transition temperature: Measured using DSC Q100 (TA Instruments).

Heat resistance (HDT, ° C): Measured according to ASTM D648.

division Impact strength Glass transition temperature transparency Flowability Mw HDT Example 1 87 156 ○ 6 54,000 136 Example 2 90 166 ○ 5 55,000 146 Example 3 89 162 ○ 6 54,000 142 Example 4 91 168 ○ 4 53,000 148 Comparative Example 1 85 145 ○ 7 50,000 125

As shown in Table 1, the polycarbonates (Examples 1 to 4) of the present invention had the same transparency and the like as those of the conventional polycarbonate (Comparative Example 1), but were excellent in mechanical properties and had excellent heat resistance I could.

Claims (15)

(1)
[Chemical Formula 1]

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms)
compound. The method according to claim 1,
R ₂ , R ₃ and R ₄ are hydrogen and R ₁ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms.
compound. The method according to claim 1,
Wherein the compound is a diol monomer used in the production of polycarbonate
compound. Carbonate precursor and the following formula 1
[Chemical Formula 1]

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms).
Polycarbonate. 5. The method of claim 4,
Wherein the polycarbonate is polymerized by further including an aromatic diol monomer different from the diol monomer in the carbonate precursor and the diol monomer represented by Formula 1
Polycarbonate. 6. The method of claim 5,
The polycarbonate is polymerized in an amount of 10 to 100% by weight of the monomer represented by the formula (1) and 0 to 90% by weight of the aromatic diol monomer based on 100% by weight of the total of the diol monomers. To
Polycarbonate. 5. The method of claim 4,
The carbonate precursor is represented by the following chemical formula 4
[Chemical Formula 4]

(Wherein X ₁ and X ₂ are each independently a halogen, a haloalkyl group, a halocycloalkyl group, a haloaryl group, an alkoxy group or a haloalkoxy group)
Polycarbonate. 6. The method of claim 5,
The aromatic diol monomer may be at least one selected from the group consisting of bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfone, bis Bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) ketone, 1,1- , Bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) cyclohexane (bisphenol Z), 2,2- Bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, (4-hydroxyphenyl) -1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane and α, ω-bis [3- (ο-hydroxyphenyl) propyl] polydimethylsiloxane Characterized in that at least one member selected from the group
Polycarbonate. 5. The method of claim 4,
Characterized in that the polycarbonate is further polymerized by further comprising a molecular weight regulator
Polycarbonate. 10. The method of claim 9,
Wherein the molecular weight regulator is a mono-alkylphenol
Polycarbonate. 10. The method of claim 9,
Wherein the molecular weight modifier is contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the total of the diol monomers
Polycarbonate. 5. The method of claim 4,
Wherein the polycarbonate has a weight average molecular weight of 10,000 to 100,000 g / mol and a glass transition temperature of 140 to 250 ° C
Polycarbonate. 5. The method of claim 4,
The polycarbonate has a heat resistance (HDT) of 120 to 230 ° C
Polycarbonate. 9. The method of claim 8,
The polycarbonate may be represented by the following general formula
(3)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are each hydrogen or an alkyl group having 1 to 10 carbon atoms, n is 0 to 445, and m is 1 to 225) Featured
Polycarbonate. Characterized in that it comprises the polycarbonate of any one of claims 4 to 14
article.

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