JPH11158245A - Polyurethane having fluorene skelton - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a stiff and chemically stable polyurethane showing thermal stability (high glass transition temperature) and film forming ability. SOLUTION: A polyurethane has a repeating unit shown by the formula described below and weight average molecular weight of 2,000-200,000 (wherein R is an alkylene group, a phenylene group which may include an alkyl group or a xylylene group which may include an alkyl group). The polyurethane is obtained by making 9,9-bis[4-(2-hydroxypropoxy)phenyl]-fluorene react with a diisocyanate in the presence or absence of a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyurethane and a method for producing the same.

[0002]

2. Description of the Related Art Polyurethane is used as a transparent conductive film, an organic semiconductor, an organic superconductor and a photosensitive material in the electric and electronic industries; optical lenses such as automobile lenses, CD pickup lenses and Fresnel lenses, and projection television screens. , As a material for a film such as a retardation film, plastic optical fiber, optical disc substrate, and the like; and in the fields of paints, fibers, synthetic leather, and the like, for example, tires, belts, packings, gears,
Widely used as a material for shoe soles.

[0003] Polyurethanes are obtained by the reaction of polyester glycols or polyether glycols with diisocyanates. As typical polyester glycols, those having a molecular weight of about 1500 to 3000 obtained from ethylene glycol and the like and adipic acid and the like are used, and as the diisocyanate, tolylene diisocyanate and the like are used.

In the reaction of polyester glycol or polyether glycol with diisocyanate, the diisocyanate is excessively reacted to synthesize a high molecular weight prepolymer having isocyanate groups at both ends, and furthermore, diamine, amino alcohol, Glycol is added to extend the chain length and to carry out an intermolecular crosslinking reaction. Polyurethanes have different physical properties depending on the type of raw materials, cross-linking conditions, etc., but generally have excellent oil resistance and abrasion resistance, but have the disadvantage of low heat resistance, and also have a film forming ability.
A material having a high refractive index suitable as an optical material is not widely known.

The present inventor has proposed a polyurethane having a fluorene skeleton as a rigid and chemically stable polyurethane having heat resistance and film forming ability (Japanese Patent Application Laid-Open No. Hei 8 (1994)).
-3260 publication).

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel polyurethane having a fluorene skeleton which is rigid and chemically stable, has a film forming ability with further improved heat resistance. An object of the present invention is to provide a novel polyurethane having a high refractive index suitable as an optical material.

[0007]

The polyurethane of the present invention has a repeating unit represented by the following formula (1) and has a weight average molecular weight of 2,000 to 300,000, preferably 30.
It is in the range of 00 to 50,000. If the weight average molecular weight is too high, the film forming ability tends to decrease. The polyurethane of the present invention is, for example, about 50 to 150 ° C.,
It has a glass transition point of about 120 ° C.

[0008]

Embedded image

In the formula (1), R represents an alkylene group (preferably an alkylene group having 1 to 10 carbon atoms, more preferably 2 to 8 carbon atoms, usually a linear alkylene group), an alkyl group (eg a methyl group) A phenylene group (for example, a toluylene group, specifically, a toluylene group represented by the following formula (2)) or an xylylene group (for example, a formula (3) Represents a xylylene group represented by

[0010]

Embedded image

The polyurethane of the present invention is, for example, 9,9-bis (4- (2-hydroxypropoxy) phenyl) -fluorene (hereinafter referred to as “BPP”) represented by the following formula (4).
F ") and a diisocyanate represented by the formula (5): OCN-R-NCO. In the formula (4), R has an alkylene group (preferably an alkylene group having 1 to 10 carbon atoms, more preferably 2 to 8 carbon atoms, usually a linear alkylene group) and an alkyl group (for example, a methyl group). (For example, a toluylene group, specifically, a toluylene group represented by the formula (2)) or an alkyl group (for example, a methyl group)
A xylylene group (for example, represents a xylylene group represented by the formula (3)).

[0012]

Embedded image

BPPF can be produced, for example, by reacting fluorenone with phenoxypropanol. Fluorenone and phenoxypropanol can be reacted, for example, by using sulfuric acid and thiol as catalysts.

The diisocyanates include, for example, ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate (hereinafter referred to as "HDI"), heptamethylene. Diisocyanate, octamethylene diisocyanate, toluylene diisocyanate (hereinafter referred to as "TDI"), xylylene diisocyanate (hereinafter referred to as "XDI") and the like can be used.

The polyurethane of the present invention can be produced efficiently by reacting about equimolar amounts of BPPF with diisocyanates. BPPF and diisocyanates can be reacted in the presence or absence of a solvent. This reaction can be completed usually by mixing BPPF and diisocyanates and, for example, stirring at a temperature of about 60 to 150 ° C. for 1 to 10 hours as needed. As for the reaction between BPPF and diisocyanates, a prepolymer having isocyanate groups at both ends is synthesized by reacting the diisocyanates in excess, and the chain length is further reduced by adding diamine, amino alcohol, glycol and the like. At the same time, the intermolecular crosslinking reaction can be performed.

The solvent is not particularly restricted but includes, for example, benzene, toluene, chlorobenzene,
o-Dichlorobenzene, dimethylformamide, dimethylacetamide, dimethylsulfoxide and the like can be used. By reacting BPPF with isocyanates in the absence of a solvent, to produce a polyurethane having higher heat resistance, for example, a polyurethane having a glass transition point of about 50 to 100 ° C, particularly about 65 to 95 ° C. Can be.

Although chlorobenzene is used as a solvent, a polyurethane having a high molecular weight can be used, although it depends on the type of isocyanate. For example, when HDI is used as the isocyanate, 40
Polyurethanes having a weight average molecular weight of at least 00, especially at least 5,000, more preferably at least 6,000, usually at most 10,000, can be produced. If TDI is used, it should be 20,000 or more, especially 30,000 or more, and even 40
Polyurethanes of 000 or more, usually 50,000 or less can be produced.

After reacting the BPPF with the diisocyanates, the resulting polyurethane can be recovered by conventional means, for example, by removing the solvent and the like, if necessary, and filtering. The recovered polyurethane can be isolated and purified by conventional means, for example, by washing with an ether solvent such as diethyl ether or a lower aliphatic alcohol solvent such as methanol.

The polyurethane of the present invention can be dissolved in various solvents, for example, N, N-dimethylformamide (DMF), tetrahydrofuran (THF), acetone and the like. A solution obtained by dissolving the polyurethane of the present invention in a solvent is applied to the surface of the base material, and the solvent is removed.
A film comprising the polyurethane of the present invention can be formed. According to the polyurethane of the present invention, 1.50
Or more, preferably 1.55 or more, more preferably 1.6
A film having the above refractive index can be formed.

[0020]

The novel polyurethane having a fluorene skeleton according to the present invention has heat resistance (specifically, a high glass transition point) and film-forming ability, and is rigid and chemically stable.

[0021]

EXAMPLES (1) Production of BPPF A mixture of 18.0 g (0.1 mol) of fluorenone, 60.8 g (0.4 mol) of 1-phenoxy-2-propanol and 0.1 g of β-mercappropionic acid was added to a mixture of 65%.
While stirring at a temperature of 16 ° C., 16 mL of 96% sulfuric acid was added dropwise thereto. After further stirring at 65 ° C. for 4 hours, the mixture was mixed with 1 part of distilled water.
00 mL was added and cooled to room temperature. The precipitate was collected by filtration to give a crude product. The crude product was purified by silica gel chromatography using 1: 1 hexane / ethyl acetate. 35.6 g of white solid product (BPPF)
(76.4% yield) was obtained.

The results of 1H-NMR analysis of the obtained product are shown in FIG. 1 and below, and the results of IR analysis are shown below. 1H-NMR (CDCl3) δ (ppm): 1.24 (d, 6H, -CH3), 1.
83 (s, 4H, -OH), 3.70-3.88 (m, 4H, -OCH2-), 4.13-4.16 (m, 2
H, -CH <), 6.75 (d, 4H, arom.), 7.11 (d, 4H, arom.), 7.25-7.3
7 (m, 6H, arom.), 7.75 (d, 2H, arom.). IR (KBr): 3400,1180
(-OH), 2871,1448,1375 (-CH3), 1246,1037 (arom.-O-CH
2), 824,748,730 cm-1 (arom.). (2) Production of polyurethane Example 1 4.67 g (10.0 mmol) of BPPF was mixed with 1.78 g (10.0 mmol) of tolylene diisocyanate (TDI).
l) was mixed at 80 ° C under a nitrogen atmosphere to obtain a uniform and transparent solution, and then heated to 100 ° C. After reacting at 100 ° C. for 4 hours, it was cooled to room temperature. The obtained crude product was washed three times with diethyl ether to obtain a product. The resulting product was identified as a polyurethane by IR. The results are shown below. The weight average molecular weight of the obtained polyurethane measured by gel permeation chromatography (GPC) was 3,800, and the glass transition point measured by scanning differential thermal analysis (DSC) was 104.0 ° C.
Met. IR (KBr): 2981,2873,1450 (-CH2-), 1731 (-NHC
OO-), 1219,1055 (arom.-O-CH2), 825,748cm-1 (aro
m.). Example 2 Internal volume 3 equipped with a reflux condenser having a drying tube and a stirrer
4.67 g of BPPF (10.
0 mmol) and 1.78 g (10.0 mmol) of TDI dissolved in 100 mL of chlorobenzene, the mixture was stirred at 100 ° C. for 4 hours, and chlorobenzene was evaporated. The obtained crude product was washed three times with diethyl ether to obtain a product.

The obtained product was analyzed by 1H-NMR (CDCl
According to 3) and IR, it was identified as polyurethane. 1H
FIG. 1 shows the results of -NMR and the results of IR are shown below.
The weight average molecular weight of the obtained polyurethane measured by GPC was 6,600, and the glass transition point measured by DSC was 117.2 ° C. IR (KBr): 2935,2873,14
55 (-CH2-), 1737 (-NHCOO-), 1214,1050 (arom.-O-CH2), 8
Example 3 1.68 g of hexamethylene diisocyanate (HDI) instead of 1.78 g (10.0 mmol) of TDI
A product was obtained in the same manner as in Example 1 except that 0.0 mmol) was used. The resulting product was identified as a polyurethane by IR. The results are shown below. The weight average molecular weight of the obtained polyurethane measured by GPC was 7,200, and the glass transition point measured by DSC was 76.1 ° C.
Met. IR (KBr): 2940,2858,1455 (-CH2-), 1711 (-NHCOO-), 1240,
1045 (arom.-O-CH2), 825,748 cm-1 (arom.). Example 4 HDI instead of 1.78 g (10.0 mmol) of TDI
Example 2 except that 1.68 g (10.0 mmol) was used.
A product was obtained in the same manner as described above. The resulting product was identified as a polyurethane by IR. The results are shown below. The weight average molecular weight of the obtained polyurethane measured by GPC was 42700, and the glass transition point measured by DSC was 104.0 ° C. IR (KBr): 2929,2858,14
50 (-CH2-), 1721 (-NHCOO-), 1240,1045 (arom.-O-CH2-),
825,748 cm-1 (arom.). Example 5 Instead of 1.78 g (10.0 mmol) of TDI, XDI
Example 2 except that 1.92 g (10.0 mmol) was used.
A product was obtained in the same manner as described above. The resulting product was identified as a polyurethane by IR. The weight average molecular weight of the obtained polyurethane measured by GPC was 3,370, and the glass transition point measured by DSC was 90.3 ° C.

(3) Film formation test Each of the polyurethanes (white solids) obtained in each of the examples was treated at room temperature with various solvents such as DMF and T
Dissolved in HF and acetone. For example, 0.1 g of the polyurethane obtained in each example was added to 10 ml of THF.
After uniformly flowing the solution dissolved in on a glass board,
When the THF was removed, a transparent film was formed in each case. In the analysis by IR in Examples 1 to 4,
The film thus formed was used.

The refractive indexes of the films formed using the polyurethanes obtained in Examples 2, 4 and 5 are shown in Table 1 together with the weight average molecular weight (Mw) and the glass transition point (Tg) of the polyurethane. For comparison, the results are shown for a polyurethane produced using 2.2-bis (4- (2-hydroxyethoxy) phenyl) fluorene instead of BPPF. Comparative Example 1 used TDI as a diisocyanate, Comparative Example 2 used HDI, and Comparative Example 3 used XDI.
DI was used. The refractive index was measured using Sodium D line having a wavelength of 589.3 nm with diiodomethane as a solution using an Abbe refractometer 4T manufactured by Atago Co., Ltd.

[0026]

[Table 1]

[Brief description of the drawings]

FIG. 1 is a chart showing 1H-NMR measurement results of BPPF used in each Example and polyurethane produced in Example 2.

Claims (3)

[Claims] 1. A polyurethane having a repeating unit represented by the following formula (1) and having a weight average molecular weight in the range of 2,000 to 300,000. In the formula (1), R represents an alkylene group, a phenylene group having an alkyl group, or a xylylene group having an alkyl group. Embedded image 2. 9,9-bis (4- (2-hydroxypropoxy) phenyl) -fluorene and OCN-R-NC
The method for producing a polyurethane according to claim 1, wherein the diisocyanate represented by O is reacted in the presence or absence of a solvent. R represents an alkylene group, a phenylene group that can have an alkyl group, or a xylylene group that can have an alkyl group. 3. The process for producing a polyurethane according to claim 2, wherein 9,9-bis (4- (2-hydroxypropoxy) phenyl) -fluorene is reacted with diisocyanates in the absence of a solvent.