JPH03163160A - Stabilization of aromatic polycarbonate and its stabilized composition - Google Patents

Abstract

PURPOSE:To improve the hot water resistance of a composition by adding a phosphorous diester to an aromatic polycarbonate obtained by subjecting a crystalline aromatic polycarbonate prepolymer to solid state polymerization. CONSTITUTION:A stabilized aromatic polycarbonate composition is obtained by adding 0.0005-0.015 pt.wt. phosphorous diester (e.g. bis(nonylphenyl) hydrogenphosphite) to 100 pts.wt. highly crystalline aromatic polycarbonate (obtained by subjecting a crystalline aromatic polycarbonate prepolymer to solid state polymerization and having a number-average mol.wt. (Mn) of 4000-100000, a weight-average mol.wt. (Mw) of 10000-200000 and a mol.wt. distribution (Mw/Mn) of 2.35-2.45 at an Mw of about 28000. This composition is excellent in hot water resistance and shows a retention of the weight-average mol.wt. >=80% under the conditions of 105 deg.C and 300hr.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for stabilizing aromatic polycarbonate, which is an engineering plastic, particularly a method for improving hot water resistance, and a stabilized aromatic polycarbonate resin composition obtained thereby. related to things.

(Prior Art) Aromatic polycarbonates are generally synthesized by the phosgene method or the melt method, and are widely used as engineering plus books with excellent transparency, impact resistance, and self-extinguishing properties. However, the hot water resistance is not necessarily sufficient, and in order to improve this, a method using a phosphorus stabilizer and an epoxy compound or a silicone compound (for Jf) is used.
Reliance and Engineering (2nd edition) vo
l. 11. p665 (1985)) has been proposed.

However, it is known that phosphorus stabilizers, which are indispensable for polycarbonate melt molding 11), have a negative effect on hot water resistance. However, if the amount of phosphorus-based stabilizer is reduced or not used, there is a problem that the self-retention properties of the polycarbonate deteriorate during melt molding, resulting in poor hot water resistance.

On the other hand, a method of adding phosphorous acid diester as a phosphorus stabilizer is also known, and Japanese Patent Publication No. 37-137750 reports a composition of aromatic polycarbonate 1 to phosphorous acid diester. According to this, the preferable addition star is 0.02 to 100 parts by weight of polycarbonate.
5 parts by weight. Also, Machimun Sho 47-12993
A combination of an aromatic polycarbonate and a diethyl phosphite is also reported in the above publication. In this case, the preferable addition amount is 0.000 parts per 100 parts by weight of polycarbonate.
01 to 2.0 parts by weight, and in the examples Gi0.
It is in the range of 0.02 to 0.1 heavy tail. As mentioned earlier, these esdel phosphate thermal stabilizers (although they have a remarkable effect on the thermal stability of melt processing and molding 1t.5),
Extremely hot water resistance and steam resistance of molded products, or 1tlJ
There is a problem in that iJ heat aging has a negative effect on the six colors of polymers. These negative effects depend on the added star, and there was a problem in that the larger the amount added, the worse the coloration of the heat-reducing water-based Yaborimer. As mentioned above, polymers that are resistant to hot water during molding and are immersed in extremely hot water ↑4 have not been obtained to date using polycarbonate resin compositions synthesized by the conventional phosgene method or Mel 1 method. There wasn't.

(Problems to be Solved by the Invention) A new aromatic polycarbonate composition with excellent stability, especially highly hydrothermal (successful steam) properties, and a method for stabilizing the same. This is what we provide.

(Means for Solving the Problems) The present inventors have solved the above problems by adding diester phosphite, which is a minor sin unthinkable in the past, to aromatic polycarbonate synthesized by solid phase polymerization. He found that the problem could be solved, and based on this knowledge, he completed the present invention.

In the present invention, a crystalline aromatic polycarbonate brevolimer is solid-phase polymerized and 1-100 parts by weight of y''J group polycarbonate is prepared by solid-phase polymerization, and 0.0.
A method for stabilizing aromatic polycarbonate in which 100 parts by weight of aromatic polycarbonate and 0.0 parts by weight of diethyl phosphite are mixed. The present invention provides a stabilized aromatic polycarbonate composition having a double hook portion of 0.0005 to 0.015.

The following is a detailed reading of Masaaki Moto.

The terminal bowl of the crystalline young group polycarbonate-1 to prevolimer used in water defense consists of a hydro:1 sill base and an aur carbonate base. This combination of end groups has a particularly fast in-phase polymerization rate, with a ratio of 10:90 to 90:1.
0, especially a range of 20:80 to 80:20. If this range is exceeded, the solid phase polymerization rate will decrease.

The prebolimer is usually an aromatic polycarbonate mainly composed of bisphenol A units, and can be expressed by the following general formula.

X is -(Koichi R or ArO11, where R is an aru group and AI' is an aromatic residue. For example, ?G-{■= {sawa). Further, there is no particular restriction on the degree of crystallinity of the crystalline prepolymer of the present invention, but the degree of crystallinity is usually 5 to 55%.
The W! (X-ray diffraction method). If the degree of crystallinity is low, it will be easy to synthesize, and if it is too high, the polymerization rate will be slow.

Various methods can be used to produce the above-mentioned crystalline aromatic polycarbonate polymer powder, but a preferred method is to crystallize a non-grade prepolymer melt having a high specific surface area morphology with a corresponding molecular star. immersed in a solvent,
This is a method of crystallizing it and pulverizing it to create a powder.

Here, the molten material having a high specific surface area is in the form of a strand, a fiber, a fine particle, a film, or the like.

Solvents used for crystallization include, for example, chloromethane, methylene chloride, coform, carbon tetrachloride,
Chloroethane, dichloroethane (various types), trichloroethane (various types), 1.
Aliphatic halogenated hydrocarbons such as ethane (various types): chlorobenbin, dichlorobenzene, etc. Aromatic halogenated hydrocarbons such as CT benzene: ethers such as Te1-rahydrofuran, diochirin, etc. Methyl diquanoate, IM ethyl, etc. esters;
Examples include carbons such as ahitone and methyl alcohol ketone; aromatic hydrocarbons such as benvin, toluene, and xylene. These solvents are 1}ITII or J:
Two or more types may be mixed and used.

Among these, acetone is also preferred for synthesizing the prebolimer with a large surface area of the present invention.

It is also possible to use a mixture of water, methanol, etc. as a poor solvent with the above solvent.

The solid phase polymerization is carried out at a temperature above the glass transition humidity and below the melting point of the crystalline prepolymer, and is in the range of 150°C to 260°C. Below 150°C, the polymerization rate is slow;
If the temperature is higher than 0'C, the polymer powders will strongly fuse together, which is not preferable.

The same phase polymerization is carried out under reduced pressure conditions or inert gas flow conditions, and polymerization is carried out while removing condensation by-products such as aromatic monohydroxy compounds such as phenol or diaryl carbonate from the system.

Various methods are known as the process of homophase polymerization, and any of these methods can be used.

Examples include tumbler type, kiln type, paddle dryer type, screw conveyor type, vibrating type, fluidized bed type, fixed bed type, moving bed type, and the like.

The number average molecular weight of the aromatic polycarbonate obtained by solid phase polymerization is usually in the range of 4,000 to 100,000, and the weight average molecular weight is usually in the range of 10,000 to 200.
The range is 000.

Although the same phase polymerization can be carried out in the presence or absence of a catalyst, non-catalytic polymerization is preferred because the color, heat resistance, and hot water resistance of the polymer produced per gram are much better.

As the polymerization catalyst, various known transesterification catalysts used for polycarbonate or polyester can be used. Examples include alkali metal salts of bisphenol A, compounds of tin and lead, and the like.

Non-grade aromatic polycarbonate which is the starting material of the present invention
- There is no particular limitation on the method of synthesizing the prepolymer, and the prepolymer can be synthesized using the various methods described below.

One is bisphenol A'l by transesterification method.
Mel 1 of bisphenol and diaryl carbonate
・Synthesis by polymerization, one method is to interfacial polycondensate bis-71-nol and phosgun in the presence of an aromatic-hinohydroxy compound such as phenol Yata Liebbruch 1-nol as a terminal capper. , a method in which a condensate of bisphenol and diaryl carbonate at a ratio of 1:2 is synthesized in advance, and this is melt-polymerized with bisphenol.One method is to synthesize an excess of phosgun and 71-nor with respect to bisphenol in interfacial polycondensation. Examples include a method in which bisphenol is newly added to a phenyl carbonate-terminated polycarbonate oligomer obtained by the reaction and then melt-polymerized.

If a prebolimer is made by the transesterification method, it is possible to synthesize an aromatic polycarbonate containing no chlorine at all, and even if phosgene is used, the prebolimer used in this process is a low-molecular star. Therefore, it is easy to make the polymer from lees, and it is possible to obtain high purity material that does not actually contain chlorine compounds.

The aromatic polycarbonate 1 to used in the present invention is this J
: Compared to the Uniphosgene method, methylene chloride, bosgene, polymerization catalyst, by-product salt, etc. are not used in the process, and it is an extremely pure polymer that is not present in the product. It is a polymer that does not contain methylene chloride and free chlorine, which is one of the leading agents of corrosion. Furthermore, the aromatic polycarbonate of the present invention was analyzed for methylene chloride by gas chromatography and for free chlorine by potentiometric titration using a silver nitrate solution as a titrant, and both of these were below the detection limit. Generally speaking, since the polymer uses a solid phase polymerization method, the polymerization temperature is lower than that of the conventional melt method, and there are almost no side reactions such as branching that cannot be carried out by the melt method.

Therefore, the aromatic polycarbonate of the present invention is
Compared to the method, the molecular star component 711 is sharper.

Generally, as the molecular star becomes larger, the molecular diameter tends to become wider, and both the solid phase polymerization method and the Mel 1 method show the same tendency. At a critical average molecular weight tJ of around 28,000,
In the solid phase polymerization method, the molecular star fraction I1 expressed as MW/Mn
1 is MW/Mn=2. 35 ~2. 4
5, and in the melt method MW /Mn = 2.6 ~ 2
. Must be 8.

Solid-phase polymerization and molecular components are the most important.

1,',l + Y1 f of molecule 6 of IJ polymerized polycarbonate is usually fvlw = 16,000 [t. 'r
Mw /Mn = 2.20 ~ 2.25, MW = 25
,000, Mw /Mn = 2.30 to 2.40, and when MW = 28,000, MMw /Mn = 2.
．． 35 to 2.45.

Even in the current molecular fan, the molecular foot distribution of the solid-phase bonded polycarbonate 1- is more in the shape of the X-type than that of the melt-processed polycarbonate 1-. Therefore, the aromatic polycarbonate 1 to be used in the present defense is cleaner and free of impurities compared to the polymers produced by the Kosugun method, and is essentially thermostable as it is free of dissimilar bonds. It is a voluminous material with excellent properties.

Also, solid phase polymerized polycarbonate is a molecular field! 5 is sharp and has few oligomers.

Aromatic polycarbonate 1, which is the main component of Masaaki Moto's composition
- is a highly crystalline polymer with a high single-crystal melting point and a sharp melting point peak.
It is clearly distinguished from the aromatic polycarbonate 1.

Aromatic polycarbonate of the present invention] 1. Heating for solid state polymerization I1. 'Because the polymer is annealed to H,
The melting point measured with differential scanning thermal star SI (D SC) has increased, and the melting point peak is sharp.

Crystal melting point (DSC peak top) is 230'C~30
At 0°C, the half value rlJ of the melting point peak is 3 to 8°C.

DSC measurements were performed under the conditions of an inert atmosphere, a gastric temperature rate of 10°C/min, and 5 to 10 mg of sample crystals.

The phosphite diester used in the present invention is one in which the two water M atoms of monononite acid (+-f2P11o3) are replaced with a hydrocarbon!; , as an example, R-0 \ (in the formula R.R' l user base, aryl, and 1;
Sub-al=t-nylaryl is shown. 〉There is also phosphorous acid di-1 sdel.

In the above formula, examples of alkyl groups are Ebru base, Bubu nore base, A Kubu nore base, Sik] Kohe=1-Sinore fu, 2
Examples include edylhexyl base, decyl base, 1-ridecyl base, lauryl base, pentaerythritol base, and sudearyl base. Further, examples of the aryl base include a fluorine base, a naphthyl base, and the like.

As the alkyl 7 reel, [yo, 1 ~ lyl base, paratersiary butyl phenyl base, 2,4-diteryl/leabutyl phenyl base, 2,6-diteryl base, paraterciary dilphenyl base, paranonylphenyl base, Examples include enyl group, dinonylphenyl group, and the like.

Preferred specific examples include diphenylhydride [1 gunphosphite (R.R' triphenyl), bis(nonylphenyl)hydrogenbosphite (R.R' trinonylphenyl), and bis{2,4-ditertiarybutylphenyl}. Examples thereof include hydrogen phosph 7-1-, dicresyl hydrogen bosphite, bis(p-tertiarybutylphenyl)hydro-gonbosphite, bis{p-hexyphenyl}hydro-gunbosphite, and the like.

The phosphite diester used in the present invention includes, in addition to those represented by the above general formula, for example:
represents alkylene, arylene, or arylalkylene. ) Jesdel phosphite can also be used.

Furthermore, those represented by the general formula (R'' is the same as above) can also be used.

Among these phosphite diesters, aromatic diester phosphites are preferred. Particularly preferred examples include diphenylhydride gunphosphie 1-, bis(nonylphenyl)hydrogenphosphie 1-, bis(2,4-
Examples include di-t-petit-ruf-1-nyl)hydrogenphosph-f-i-1.

These phosphorous acid diesters may be used alone or in a mixture.

The addition loss of the phosphite diester used in the present invention is 0.
0005 to 0.015 times, more preferably o.
ooos~0. The range is 0.009 parts by weight. 0.
If it is less than 0.005 parts, the thermal stability will be poor, and if it is more than 0.015 parts, the hot water resistance (steam resistance) will be poor.

It is important to mix the aromatic polycarbonate and phosphite diester of the present invention uniformly.
It is preferable to homogenize the mixture in advance using a tumbler or the like.

The mixture is typically pelletized through an extruder to produce a homogeneous aromatic polycarbonate ffi compound.

Note that since the amount of phosphite diester added is small, the additive may be diluted in a solvent such as acetone, added to the polymer, and then the acetone may be removed by drying. The aromatic polycarbonate 1 composition of the present invention thus obtained has excellent hot water resistance;
Serious crime average molecular weight retention rate of 80% or more in time.

〔Effect of the invention〕

The resin composition stabilized by the stabilization method of the present invention is a composition consisting of a solid-phase polymerized aromatic polycarbonate and a phosphorous diester, and is compared to the aromatic polycarbonate of the conventional phosgene method and Yamelt method. It has excellent heat resistance and can be used as a variety of molding materials.
This guarantees excellent effects.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

The molecular weights are the average molecular star (hereinafter abbreviated as Mn) and the average double star molecular star (abbreviated as Mw) measured by gel permeation chromatography (GPC), and are the terminal groups in the prepolymer. The results were analyzed by high-performance liquid chromatography or NMR.The surface area was measured using a clear 1000 mm sample using Auresorb Model 210G-02 manufactured by Shimadzu Corporation.

The extrusion molding was performed using Modern Machinery's MJEC-10 copper extrusion molding machine, and the resin temperature was 300℃ and the mold was 90℃.
A STM No. 4 dumbbell was manufactured. The tensile test was conducted at 50 am/bin.

Example 1 A number average molecule of 14,100 synthesized from bisphenol A and diphenyl carbonate with a terminal hydroxyl group of 3
Crystalline prebolymer 11K with a surface area of 1.5 m/g having 4% and 1 to 66% terminal phenylcarbonate groups.
3 was subjected to solid phase polymerization using a tumbler type solid phase polymerization vessel as shown in 70.1). As a polymerization condition, a small amount of nitrogen is leaked into the system! At the same time, under a reduced pressure fl of 1 to 2 tOrr using a vacuum pump, the temperature was raised from 180°C to 220°C over 60.1 hours, and then the temperature was held at 220°C for 5 hours to carry out polymerization. As a result, Mn = 12 ,500, Mv =28
, 000 polymers were obtained.

This polymer had a melting point of 271°C and a half width of 4.3°C. A DSC unit is shown in FIG.

Bis(
Nonylphenyl) Hydrogunbosphite 0.39 was mixed in Henschel MIKI 1 NO, and then injection molded at 300'C to produce dumbbells. This dumbbell is 105
A hot water resistance test was carried out by immersing it in hot water at °C. The results are shown in Table 1.

Example 2 Aromatic polycarbonate 1 obtained in the same manner as Example 1
Example 1
I passed the index test J1 as a shrine. The results of severe hydrothermal death are shown in Table 1.

Example 3 In the same manner as in Example 1, 0.21 g of bis(nonylphinyl)hydrogunbosphi 1- was used instead of 0.3 g, mixed in Henshi 1 Lumigily, and then index molded and tested. Got a piece. Table 1 shows the results of a hydrothermal test on index-molded dumbbells.

Example 4 The procedure was carried out in the same manner as in Example 1, using 0.3 g of bis(2,4 ditersi 1!ributyl phenyl) hyde[1 gunbosphenyl] instead of bis(nonylphenyl>hydrogen phosphite I). An index test piece was obtained in the same manner as in Example 1. The results of the extreme hydrothermal test are shown in Table 1.

Comparative Example 1 Aromatic polycarbonate synthesized by the phosgene method [
Number average molecular MI0,800, double star average molecular dragon 28,0
00, methylene chloride residual i50 ppm (gas chromatographic analysis method>, free chlorine 12 ppm (potentiometric titration method using silver nitrate solution>, crystal melting point 229° C1 peak half value rl J 15° C.) was added to the powder ioKy with bis(
After mixing 0.39 g of (nonylphenyl)hydrogen phosphite in a Henschel Michilly, the mixture was extruded at 300'C to produce dumbbells. Hold this dumbbell at 105°C.
A hot water resistance test was conducted by immersing it in hot water. The results are shown in Table 1.

Comparative Example 2 Bis(nonyl phenyl) hydrogen bosphite 0.
0.0g instead of 3g. A dumbbell was produced in the same manner as in Example 1 except that 0.025 g was used. Table 1 shows the results of the hot water test I.

Comparative Example 3 An indexed or shaped dumbbell was assembled in the same manner as in Example 1, except that 4 g of bis{nonyl phenyl}bosphite was used instead of 0.3 g. Table 1 shows the hot water resistance test results.

? Example 5 Bisfurinole A and diphenylene carbonate l~j;
The number average molecule ffl4,200 synthesized by
A crystalline prepolymer with a surface area of 1.2 Trt/ta and having terminals of
■: 1-phase coupling was performed in the same manner as in Example 1 using a material containing ppm, Mn = 14,000, Mw
= 35,000 polymers were obtained. A hot water resistance test was conducted in the same manner as in Example 1, and the result was 300 1 AT u
The elongation at break after U was 91% and the molecular weight (MW) retention rate was 92%, which was good.

Comparative Example 4 Polycarbonate was synthesized by a melt method using bisphenol A and diphenyl carbonate. The catalyst was a bisphenol A notorium salt added to bisphenol A at a concentration of 5 ppIII/JIL. While removing phenol from the condensate, the polymerization temperature was gradually raised from 180'C until finally reaching 310'C. The number average molecular star of the obtained aromatic polycarbonate 1 is 10,500
, the double star average molecular loss is 28,300 and Mw /Mn is 2
．． It was 7. 0.0 kg of bis<nonylphenyl>hydrogen phosphite to 10 kg of this aromatic polycarbonate.
After mixing 3 g in a Henschel mixer, injection molding was performed at 300°C to produce dumbbells. Table 1 shows the physical property i/r value results.

(Margin below) 4.

[Brief explanation of the drawing]

FIG. 1 is a DSC sample of the polymer obtained in Example 1.

Claims (1)

[Claims] 1. 0.0005 to 0.015 parts by weight of a phosphorous diester is mixed with 100 parts by weight of an aromatic polycarbonate obtained by solid phase polymerization of a crystalline aromatic polycarbonate prepolymer. A method for stabilizing aromatic polycarbonate. 2. A stabilized aromatic polycarbonate composition comprising 100 parts by weight of aromatic polycarbonate and 0.0005 to 0.015 parts by weight of phosphorous acid diester. 3. The stabilized aromatic polycarbonate composition according to claim 2, wherein the aromatic polycarbonate is a highly crystalline aromatic polycarbonate.