JPH04323246A - Indene polymer composition - Google Patents

Abstract

PURPOSE:To obtain a moldable indene polymer composition holding characteristics of an indene polymer. CONSTITUTION:An indene polymer composition improved in moldability is obtained by blending an indene polymer with a specific amount of a specified plasticizer. Thereby, the indene polymer composition, improved in transparency, heat resistance, low hygroscopicity and adhesion, having a low birefringence and excellent in moldability is obtained. As a result, the indene polymer can extensively be used as an optical material.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indene polymer composition that has excellent transparency, heat resistance, low moisture absorption, adhesion to metals, etc., and low birefringence. Due to the above properties, the polymer composition can be used as a molding material in various fields, and is particularly useful as an optical material for lenses, optical disk substrates, and the like.

0002

BACKGROUND OF THE INVENTION For the polymerization of indene, cationic polymerization or coordination polymerization using a vanadium catalyst or the like has been known (Japanese Patent Application Laid-open No. 1-167314). However, as mentioned above, only the manufacturing method is known, and despite its good optical properties, it is not used as an actual industrial molding material.

0003

[Problems to be Solved by the Invention] Although the glass transition point of indene polymer is high at 200°C or higher, when used as a molding material, it is extremely brittle and cannot be molded using general methods such as injection molding. there were. For this reason, indene polymers have not been used industrially, although they have various properties. Therefore, it has been desired to obtain a moldable indene polymer.

0004

[Means for solving the problem] Therefore, the present inventors
As a result of extensive research in order to obtain a moldable indene polymer that maintains the high heat resistance, transparency, and low water absorption properties of indene polymers, we found that injection The present invention was completed based on the discovery that a moldable indene polymer composition can be obtained and that the birefringence of molded pieces thereof is small.

That is, an object of the present invention is to provide an indene polymer composition that has excellent transparency, heat resistance, low moisture absorption, adhesion to metals, etc., and has low birefringence. The gist is that in an indene polymer composition comprising 60 to 95% by weight of an indene polymer and 5 to 40% by weight of a plasticizer, the plasticizer has a boiling point of 300°C or higher and a solubility parameter of 7.5 to 9. 8 [cal/cm3]1/2 and a pour point of 30°C or less.

The present invention will be explained in detail below. The indene polymer used in the present invention can be produced by various conventionally known methods. For example, in addition to cationic polymerization using boron trifluoride or tin tetrachloride, coordination polymerization using a Ziegler catalyst may also be used.

The indene polymer of the present invention includes an indene homopolymer, a copolymer with an α-olefin polymer, or a mixture mainly composed of these polymers. The α-olefin polymer used in the above copolymer includes ordinary low density polyethylene, high density polyethylene,
Examples include homopolymers such as polypropylene and polybutene, and copolymers thereof.

In the case of a copolymer with an α-olefin polymer or a mixture thereof, the content of the α-olefin polymer is preferably within a range that does not impair the properties of the indene homopolymer, and is usually 30% by weight or less, More preferably, it is 20% by weight or less. Indene polymer raw materials include indene and hydrocarbon groups having 1 to 6 carbon atoms in the indene ring.
A combination of seven molecules and a mixture thereof can also be used. Specifically, these monomers include 1-methylindene,
2-methylindene, 3-methylindene, 4,5,6
, 7-tetramethylindene and the like.

[0009] Catalysts used for cationic polymerization include:
Boron trifluoride, aluminum halide, tin tetrachloride, titanium tetrachloride, or as an adduct of these Lewis acids and electron donors, boron trifluoride, diethyl ether complex,
Tin tetrachloride, trichloroacetic acid complex, etc. are used. The solvent used for the polymerization reaction is methylene chloride, chloroform,
Halogenated hydrocarbons such as dichloroethane and chlorobenzene, or aromatic hydrocarbons such as benzene are used.

[0010] The polymerization temperature is -100°C to 50°C, and it is produced according to a conventional cationic polymerization recipe. The obtained polymer is washed with alcohol or alcohol containing hydrochloric acid to remove the catalyst. Further, examples of the method using coordination polymerization using a Ziegler catalyst include a method using a vanadium-containing catalyst. As a vanadium component, the general formula VO(OR)p Xq or V(OR)r
Xs (X: halogen, R is a hydrocarbon group having 1 to 22 carbon atoms, p, q: 0 to 3, p + q: 2 to 3, r, s: 0 to 4
, r+s: 3-4) can be used.

More specifically, VOCl3, VO(O-
C2H5)Cl2,VO(O-iso-C3H
7) Cl2, VO(O-n-C4H9)Cl2
,VO(O-C2H5)3,VOBr2,V
Cl4, VOCl2, VO(O-n-C4 H9
) 3 etc. can be exemplified. As the halogenated organoaluminum compound catalyst component,
A compound represented by the general formula AlXnR3-n (X: halogen, R: hydrocarbon group having 1 to 12 carbon atoms, n: 1 to 2) can be used.

Specifically, Al(C2H5)2Cl
, Al(C2 H5 )2 Br, Al(C4H9 )
2 Cl, Al2 (C2 H5 )3 Cl3 ,A
l2 (C4 H9 )3 Cl3 , Al2 (C2
H5)3Br3,Al(C2H5)Cl2
, Al(C3 H7 )Cl2 , Al(C4 H9
) Br2, etc. can be exemplified. When polymerizing indene using these two components, the usage ratio of the two components is Al
/V molar ratio of 1 or more, preferably 3 to 100.

In the polymerization of indene, it is possible to use indene as both a monomer and a solvent, and it is also possible to use an inert solvent. Hydrocarbons having 4 to 20 carbon atoms are used as this inert solvent, and specifically, pentane, hexane, heptane, octane, cyclohexane,
Benzene, toluene, xylene, etc. can be used.

The polymerization conditions are not particularly limited, but the polymerization temperature is -50 to 200°C, preferably -20 to 130°C.
Performed at °C. The indene polymer obtained as described above is essentially an amorphous highly transparent polymer. Moreover, the weight average molecular weight of the indene polymer is preferably in the range of 50,000 to 400,000 in terms of polystyrene. When the molecular weight is above the upper limit, birefringence is large, and when the molecular weight is below the lower limit, there is a problem in moldability.

[0015] The plasticizer to be added to the indene polymer has a boiling point of 300°C or higher and a solubility parameter of 7.5 to 7.5.
9.8 [cal/cm3] 1/2, and the pour point is 30
It is important that the aromatic compound has a temperature below ℃. Note that plasticizers with polar groups such as dioctyl phthalate and dinolyl phthalate are also effective in the present invention, but since the low water absorption of the indene polymer is impaired, they are not suitable for applications requiring low water absorption. More preferred are aromatic hydrocarbons consisting only of carbon and hydrogen as constituent elements.

Specific examples thereof include long-chain alkylbenzenes, long-chain alkylnaphthalenes, liquid styrene oligomers, and liquid nucleus-substituted styrene oligomers. Boiling point is 300℃
If it is less than that, it is not preferable because scattering occurs during molding. Furthermore, if the solubility parameter is outside the above range, the compatibility with the indene polymer will be poor, causing problems in moldability and transparency.

[0017] If the pour point is 30°C or higher, mixing will not be sufficient and the plasticizing effect will be insufficient, which is not preferable. The above plasticizer is added to the indene polymer in an amount of 5 to 40% by weight, preferably 15 to 30% by weight. The resulting composition has a glass transition temperature of 100 to 160°C, preferably 1
The temperature is 20-160°C.

The above-mentioned mixing is not particularly limited, but for example, after mixing the indene polymer powder with a liquid plasticizer, or after co-precipitating and drying a solution mixture of the two, an extruder, a blower, etc. Examples include a method of melt-kneading using a kneader such as a lavender plastograph or a Banbury mixer. In the present invention, the resin obtained as described above is usually mixed with a heat stabilizer and then molded. Examples of the heat stabilizer include hindered phenol heat stabilizers, sulfur heat stabilizers, phosphorus heat stabilizers, and the like. A combination of a hindered phenol heat stabilizer and a phosphorus heat stabilizer is preferred from the viewpoint of improving heat deterioration resistance.

The hindered phenol heat stabilizer employed in the present invention is tetrakis[methylene-3-(3
, 5-di-t-butyl-4-hydroxyphenyl)propionate methane, 3,9-bis[1,1-dimethyl-
2-{β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl)-2,4
, 8,10-tetraoxaspiro[5,5]undecane, 1,3,5-tris(3,5-di-t-butyl-4-
Hydroxybenzyl-s-triazine-2,4,6(1
H,3H,5H)-trione, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-
Examples include hydroxybenzyl)benzene and the like.

Further, as the phosphorus-based heat stabilizer, tetrakis(2,4-di-t-butylphenyl)-4,4'-biphenylene phosphonite, bis(2,6-di-t-butyl-4 -methylphenyl)pentaerythritol di-phosphite and the like. The suitable amount of each of these stabilizers added is 0.01 to 1% by weight.

There are no particular restrictions on the method of mixing these stabilizers with the resin composition of the present invention, but usually the resin and stabilizer are mixed using a ribbon blender, tumbler blender, Henschel mixer, etc., and then a Banbury blender is used. The mixture is melt-kneaded using a mixer, single-screw extruder, twin-screw extruder, etc., and formed into pellets. By injection molding the pellets thus obtained at 250 to 300° C., it is possible to obtain a molded article with excellent optical properties, heat resistance, low water absorption, adhesiveness, and a small birefringence. Further, other polymer additives may be added as necessary.

[0022]

[Examples] Next, the present invention will be further explained by Examples and Comparative Examples.
Although the present invention will be described in detail, the present invention is not limited to the following examples unless it exceeds the gist thereof. In addition, various physical properties in the following examples and comparative examples are limited by the following method. (2) Weight average molecular weight: Measured by gel permeation chromatography (GPC) in the same manner as polystyrene using THF as a solvent to determine the weight average molecular weight in terms of polystyrene.

■ Glass transition point (Tg): Du P
It was measured using a differential scanning calorimeter (DSC) model 9900 manufactured by on't. ■ Injection molding and birefringence measurement: Injection molding was performed using Nippon Steel's 0.
Cylinder temperature 200-280 using 1oz injection molding machine
The test was conducted at ℃ to obtain a test piece of 50 mm x 5 mm x 1.5 mm. Birefringence measurement was performed using a polarizing microscope, measuring 2 points from the edge of the specimen.
The 0 mm position was measured.

■Measurement of saturated water absorption rate: Measurement of saturated water absorption rate:
After being left at 50% RH for 2 weeks or more, measurements were performed using the following method. Moisture in polymers can be measured using a trace moisture measuring device (Karl Fischer coulometric titration meter) model CA-06 manufactured by Mitsubishi Chemical Corporation, a moisture vaporizer model VA-06 (manufactured by the same company), and Aquamicron AS/CS as a coulometric reagent. (manufactured by the same company). 1-2g of polymer heated to 150-250℃ in a heating furnace
The mixture was heated to 200 to 300 ml/min to drive out moisture with dry N2 gas, and the moisture was introduced into an electrolytic cell containing a coulometric reagent for coulometric titration.

■ Measurement of pour point: JIS K 2
Measured by 265. Example of producing indene polymer In a 500 ml flask purged with nitrogen, 40 g of indene was added.
Add 360 ml of dichloromethane, bring the internal temperature to -70°C, add 4.7 g of tin tetrachloride and 2.8 g of acetic acid trichloride, and -
The reaction was carried out at 70°C for 100 minutes.

The reaction solution was then poured into 1.5 liters of methyl alcohol, the precipitate was filtered off, and tetrahydrofuran,
The solution was redissolved and reprecipitated with methyl alcohol, and the precipitate was filtered off and washed with 300 ml of methyl alcohol. The yield is 39
It was g. The obtained polymer had a Tg of 202°C and a molecular weight of 145,000. Example 1 20% by weight of alkylbenzene oil (SAS-LH Nippon Oil Co., Ltd.) was mixed with the polyindene obtained in the production example to prepare bis(2,6-di-t-butyl-methylphenyl).
0.2 parts each of pentaerythritol diphosphite and 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene were added, and the mixture was heated at 23°C. Made into pellets.

The obtained pellets were injection molded using a 0.1 oz injection molding machine at a cylinder temperature of 260° C., and the birefringence and water absorption were measured. Example 2 The same procedure as in Example 1 was conducted except that dioctyl phthalate was used instead of the alkylbenzene oil.

Comparative Example 1 The same procedure as in Example 1 was carried out except that paraffin oil was used instead of the alkylbenzene oil. The pellet molded product was cloudy and the composition was brittle and crushed during molding, so no molded pieces could be obtained. Comparative Example 2 When the same procedure as in Example 1 was carried out without adding alkylbenzene oil, the molded piece was crushed during molding and no molded piece was obtained.

Comparative Example 3 Polystyrene pellets (HH, -200, Mitsubishi Kasei Polytec Co., Ltd.) were used instead of the pellets obtained in Example 1.
The same procedure as in Example 1 was carried out except that . The physical properties of the plasticizer used are summarized in Table 1, and the results of Examples and Comparative Examples are summarized in Table 2. The results show that the composition of Example 1 has a low water absorption and low birefringence, and the composition of Example 2 has a high water absorption.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Effect of the invention] Conventionally, indene polymers were rarely used due to moldability problems despite their excellent optical properties, but with the present invention, indene polymers have excellent birefringence and good moldability. Indene polymer molded products can be easily obtained. As a result, moldable indene polymer compositions with superior properties of indene polymers have become available for use in optical materials and a wide range of other applications.

Claims (2)

[Claims] Claim 1. An indene polymer composition comprising 60 to 95% by weight of an indene polymer and 5 to 40% by weight of a plasticizer, wherein the plasticizer has a boiling point of 300°C or higher and a solubility parameter of 7.5 to 40% by weight. 9.8 [cal/cm3] 1/
2, and is an aromatic compound having a pour point of 30° C. or lower. 2. An indene polymer composition, wherein the aromatic compound according to claim 1 is an aromatic hydrocarbon consisting only of carbon and hydrogen as constituent elements.