JPH03265651A - Aromatic polycarbonate resin composition - Google Patents

Abstract

PURPOSE:To prepare the title compsn. improved in resistance to heat and hydrolysis by compounding an arom. polycarbonate polymer with a phosphite compd. and a hindered phenol compd. CONSTITUTION:An arom. polycarbonate polymer [e.g. a polymer obtd. from a dihydric compd. such as 2,2-bis(4-hydorxyphenyl)propane] is compounded with a phosphite compd. (e.g. a compd. of formula I) and a hindered phenol compd. [e.g. a compd. of formula II (wherein R is a 1-30C hydrocarbon group)] to give the title compsn., which is excellent in resistance to heat and hydrolysis and useful in many application areas as an engineering plastic.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides an aromatic polycarbonate polymer with a specific phosphite compound and a specific hindered phenol compound that contribute to thermal stability. The present invention relates to a heat-resistant and stable aromatic polycarbonate resin composition.

BACKGROUND OF THE INVENTION Significant effort has been expended in preparing heat-stable polycarbonate compositions that are color stable at the high molding temperatures typically used to make polycarbonate molded articles. A large number of additives have been found to be very suitable for rendering polycarbonates heat and color stable. Particularly useful among these are triorganophosphites, such as those disclosed in US Pat. No. 3,305,520. Also, U.S. Patent Nos. 3,729,440 and 3,
No. 953,388 discloses thermally stable aromatic polycarbonates containing phosphinites and epoxy compounds. Additionally, U.S. Pat. No. 3,794,629 discloses chemically stable aromatic polycarbonates containing oxetane phosphites, and U.S. Pat. No. 3,978,020 describes thermally stable aromatic polycarbonates containing phosphonites and epoxy compounds. Polycarbonates are each disclosed.

(Problems to be Solved by the Invention) Conventionally, various phosphorus compounds, particularly phosphite compounds, have been added to improve the thermal stability of aromatic polycarbonates. However, these phosphites have adversely affected the hydrolytic stability of the resulting polycarbonate resin compositions.

(Means for Solving the Problems) The present inventors have discovered that an aromatic polycarbonate composition obtained by blending a specific phosphite compound and a specific hindered phenol compound into an aromatic polycarbonate polymer can be molded at high molding temperatures. There is no change even after exposure,
Furthermore, we have found a heat-resistant, stable aromatic polycarbonate resin composition with improved hydrolytic stability that does not cause a decrease in tensile strength or impact strength caused by a decrease in molecular weight.

The present invention provides: (1) An aromatic polycarbonate resin composition characterized in that a phosphite compound and a hindered phenol compound are blended into an aromatic polycarbonate polymer.

(2) The phosphite compound described in item 1 has the following structural formula (
A phosphite compound having I).

(3) The hindered phenol compound described in item 1 has the following structural formula (II).

(However, R represents a hydrocarbon group having 1 to 30 carbon atoms.) In the present invention, the aromatic polycarbonate polymer is prepared by using a divalent hydroxy compound represented by the general formula (III It can be produced by transesterification method or transesterification method.

1 (R1, R2, R3, R4 are hydrogen, a linear or branched alkyl group having 1 to 8 carbon atoms, or a phenyl group, and X is a halogen atom, n = o to 4, m = 1 to 4 ) Specific representative examples include the following compounds.

A divalent hydroxy compound classified into general formula (III) and 2,2-his-(4-hydroxyphenyl)propane.

2.2-bis-(4-hydroxyphenyl)butane, 2
, 2-bis-(4-hydroxyphenyl)-4-methylpentane, 2,2-bis-(4-hydroxyphenyl)
Octane, 4,4'-dihydroxy-2,2,2-triphenylethane, 2,2-bis-(3,5-dibromo4-hydroxyphenyl)propane, and the like.

Examples of divalent hydroxy compounds classified into general formula (IV) include 2,2-bis-(4-hydroxy-3-methylphenyl)propane, 2,2-bis=(4-hydroxy-3
-isopropylphenyl)propane, 2,2-bis-(
4-hydroxy3-see, butylphenyl)propane, 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)propane.

Examples include 2.2-bis-(4-hydroxy-3-tert-butylphenyl)propane. General formula (V
) as a divalent hydroxy compound classified as 1.1'
-bis-(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1'-bis-(4-hydroxyphenyl)-m-diisopropylbenzene, and the like. As a bisphenol classified as general formula (■),
1,1-bis-(4-hydroxyphenyl)cyclohexane is mentioned. Furthermore, the general formula (mL(IV), (
2 or 3 or more types selected from VL (Vl)
It is also possible to produce copolymerized polycarbonates in combination with hydric phenols. Furthermore, structural formula (I) used in the present invention is bis(2,6-sheetbutyl4-methylphenyl)pentaerythritol-di-phosphite and structural formula (III) is octadecyl-3-(3',5
'-di-t-butyl-4-hydroxyphenyl)propionate is preferred, and the amounts of these compounds added are o,
oi to 0.5% by weight, preferably 0.02 to 0.2
Weight%. If the amount of stabilizer added is less than this range, the deterioration prevention effect will be insufficient, and if the amount added exceeds this range, bleeding may appear in injection molded products, etc., and mechanical properties may deteriorate, so it is not preferable. . The method of mixing these stabilizers with the aromatic polycarbonate polymer is not particularly limited, but the polymer and stabilizer are usually mixed using a ribbon blender, tangler blender, Henschel mixer, etc., and then a Banbury mixer, - shaft extruder,
The mixture is melt-kneaded using a twin-screw extruder and formed into pellets.

The polymer obtained in this way is used in general engineering and as a plastic material, but especially for outdoor applications such as outdoor lighting equipment, window glass, fences, microwave ovens, etc.
Suitable as a material for applications that are exposed to high temperature and humidity, such as tableware, tanks, and transport pipes.

It can also be applied to heat-sensitive elements such as electric blankets and carpets, various hoses, tubes, hot melt adhesives, and the like.

The present invention will be described below with reference to Examples, but the present invention includes:
The invention is not limited to these examples.

(Example) Example 1 2.2-bis(4-hydroxyphenyl)propane 22
8 parts by weight, potassium borohydride (10'mo1% based on the charged dihydroxy compound), and 214 parts by weight of diphenyl carbonate were added, stirred at 1800C for 1 hour under nitrogen, and then gradually heated to 250°C. The pressure inside is also 2m
It was lowered to mHg. Continue to raise the temperature to 280'C10.5mm
Polycarbonate was obtained by reacting with Hg for 2 hours. This polycarbonate is almost colorless and transparent, and contains methylene and
The intrinsic viscosity [,] measured in chloride solution at 20 °C is 0.519 [rll = 1.11 × 10-' (
Mv) 0.82 [Encyclopedia of Polymer Science and Technology, Volume 10, Page 732, 1969, John Quiley and Sons, Inc. Encyclopedia of Polymer
5science and Technology V
ol 10 P732; John Wiley &
The average molecular weight Mv calculated using the formula 5ons Inc. (1969)] was 29.900. 254 g of the polycarbonate thus obtained) and a screw (2
, 6-di-t-butyl-4-methylphenyl)pentaerythritol-di-phosphite) 0.254 g (0.1% by weight based on the polymer) and octadecyl-3-(3'
, 0.254 g of 5'-di-t-butyl-4-hydroxyphenyl) propionate (0.1% by weight based on the polymer) was mixed in a tumbler blender (Matsui Seisakusho Niskabee 50; 5KB-50), and Axial extruder (Haakebuteller Product HBI System 90-HAA
KE Buchler Product HBI Sys
tem 90) to form a pellet.

In addition, as an evaluation of heat resistance, a heating rate of 10° in a nitrogen stream was used.
Thermal decomposition behavior was measured using a differential thermogravimetric analyzer (manufactured by Rigaku Denki Co., Ltd.) under conditions of C/min. Decomposition start temperature (T
ci) is 433°C1 the temperature at which the weight loss reaches 5% (T5
) is 472°C. The temperature at which the weight loss reaches 10% (TIO
) was 4908C.

In addition, in order to evaluate the hydrolysis resistance, 50%
Create a sheet of mm x 50 mm x 0.6 mm thick and 90'
The sample was suspended in a C1100%RH constant temperature and humidity bath to measure the decrease in molecular weight due to hydrolysis. 90°C1100%RH
After 30 days under (relative humidity) conditions, the molecular weight retention rate with respect to the initial molecular weight was 89.8%, and the appearance of the sheet was colorless and transparent, with no abnormalities observed.

Example 2 2.2-bis(4-hydroxyphenyl)propane 22
8 parts by weight to 0. IN was dissolved in an aqueous sodium hydroxide solution, 214 parts by weight of diphenyl carbonate and dichloromethane were added, and phosgene gas was introduced while stirring the mixture vigorously. The resulting viscous solution was separated and dichloromethane was distilled off from the dichloromethane solution, yielding almost colorless polycarbonate. This was further washed with methanol several times, and after drying, the viscosity average molecular weight was measured in the same manner as in Example 1. 'f;) (v = 28,000
Met. It was made into pellets in the same manner as in Example 1. Also,
The heat resistance and hydrolysis resistance were evaluated in exactly the same manner as in Example 1, and the results are shown in Table 1.

Example 3 A reaction was carried out under exactly the same conditions as in Example 1, with the addition of 4-dimethylaminopyridine (10-2 mo1% based on the charged dihydroxy compound) instead of sodium borohydride to obtain a polycarbonate. Further, in the same manner as in Example 1, the pellets were formed into pellets and their heat resistance and hydrolysis resistance were evaluated. The results are shown in Table 1.

Example 4 2.2-bis(4-hydroxyphenyl)propane 11
4 parts by weight (50 mol%), 170 parts by weight of 2,2-bis(4-hydroxy-3-t-butylphenyl)propane (
50 mol %) and imidazole (10-2 mol % based on the charged dihydroxy compound) were added, and the reaction was carried out under exactly the same conditions as in Example 1 to obtain a polycarbonate copolymer. The pellets were made into pellets in exactly the same manner as in Example 1, and the heat resistance and hydrolysis resistance were evaluated. Table 1 shows the results.
It was shown to.

(Comparative Example) Comparative Example 1 Bis(2,6-
Sheetbutyl-4-methylphenyl)pentaerythritol-di-phosphite and octadecyl-3-(3',
The pellets were made into pellets without adding 5'-di-t-butyl-4-hydroxyphenyl)propionate, and the heat resistance and hydrolysis resistance were evaluated. The results are shown in Table 1.

(Effects of the invention) As shown in the results in Table 1, by adding a specific phosphite compound and a specific hindered phenol compound to an aromatic polycarbonate polymer, the heat resistance and hydrolysis resistance of the resin composition obtained It has improved properties and can be used in various fields as an engineering plastic material.

Claims (3)

[Claims] (1) An aromatic polycarbonate resin composition characterized by blending a phosphite compound and a hindered phenol compound with an aromatic polycarbonate polymer. (2) The phosphite compound according to claim 1 has the following structural formula (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (3) The hindered phenol compound according to claim 1 has the following structural formula (II). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) (However, R represents a hydrocarbon group having 1 to 30 carbon atoms.)