JPH02199119A - Novel heat-resistant transparent resin - Google Patents

Abstract

PURPOSE:To obtain a heat-resistant transparent resin which can give a molding having a high transparency, sufficiently high mechanical properties and a low water absorptivity by using units comprising two specified kinds of tetrahydrofuran skeletons in a specified ratio and having a number-average MW in a specified range. CONSTITUTION:This resin is composed of 10-90mol% each of two kinds of repeating units comprising tetrahydrofuran skeletons of formulas I and II and having a number-average MW (in terms of the MW of PS) of 5000-20000 as determined by gel permeation chromatography. Thus, a resin which can give a molding having high heat resistance, sufficiently high mechanical properties, a relatively small water absorptivity and a small optical strain can be provided. This resin can be produced by well-known cationic polymerization of 2,3- dihydrofuran and 2,3-dihydro-2,2-dimethylfuran as starting materials in the presence of an initiator.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides various molded products that have excellent transparency, high heat resistance, sufficient mechanical properties, and low water absorption. The present invention relates to a resin having a tetrahydro-7-lane skeleton.

(Prior Art) It is known that a polymer having a tetrahydrofuran skeleton can be obtained from K by cationically polymerizing a 2.3-dihydrofuran derivative in the presence of an appropriate initiator. For example, Journal of Chemical 5oci.
ety.

1954, p. 3766, describes polymers obtained by cationic polymerization of KFi, 2,3-dihydrofuran, 2,3-dihydro-5-methylfuran, etc. with a boron initiator, and also in PolymerJour.
nal l vol. 6 p. 415 (1984) contains 2,3
-dihydrofuran, living cationic polymerization of 2,3-dihydro-5-methylfuran is described. However, these sentences # or.

Any other omniscient literature only states that a polymer having a tetrahydrofuran skeleton can be obtained by cationically polymerizing a 2,3-dihydrofuran derivative in the presence of an appropriate initiator; There is no mention of various physical properties such as mechanical properties and thermal properties of the resulting molded product.

[Problem to be solved by the invention]

The present inventors investigated poly(2゜3-tetrahydrofuran diyl), a polymer obtained by cationic polymerization of 2,3-dihydrofuran, and found that this polymer had excellent transparency and heat resistance. It has been found that various molded products made of dog meat and having excellent mechanical properties can be obtained. However, as a result of further detailed study, it was found that molded products obtained from this polymer have a relatively high water absorption rate.
It has been found that this method is not necessarily satisfactory for applications requiring low water absorption. This is because 2,3-dihydrofuran is relatively easier to produce than 2-hydroxytetrahydrofuran or 1,4-butanediol.

In order to further increase the practical value of this polymer.

A method of reducing the water absorption of such polymers is highly desired.

[Means to solve the problem]

As a result of intensive studies in view of the above objectives, the present inventors discovered that 2,3-dihydrofuran and 2,3-dihydro C1-2,
The present inventors have discovered that a polymer obtained by copolymerizing 2-dimethylfuran in an excessive proportion satisfies the above objects, and have completed the present invention. That is, according to the present invention, 1 consists essentially of two kinds of tetrahydrofuran skeletons represented by the following repeating unit 1 and repeating unit 3.
When the molecular weight is measured by gel permeation chromatography, the number average molecular weight in terms of polystyrene is 50.
A heat-resistant transparent resin having a molecular weight of 0.00 to 200,000 is provided.

unit! and... are each present in the range of 10 to 90 moles, preferably 20 to 80 moles. If the unit [ is smaller than 10%, the water absorption rate of the obtained molded product is large, and if the unit is larger than 90 mol, the mechanical strength of the molded product is not necessarily satisfactory. It's not at the level I can do it.

The resin of the present invention needs to have a molecular weight within the range of 5,000 to 200,000 in terms of polystyrene equivalent number average molecular weight when measured by gel permeation chromatography.

It is within the range of 10,000 to 150,000. When the molecular weight is less than 5,000, the mechanical strength of the obtained molded product is not necessarily sufficient (and when it is greater than 200,000, the moldability of the obtained resin is undesirable).

The resin of the present invention can be produced by known cationic polymerization using 2,3-dihydrofuran and 2,3-dihydro-2,2-dimethylfuran as starting materials in the presence of a suitable initiator. For example, 2,3-dihydro7rane (!:
2,3-dihydro 2,2-dimethylfuran is 10
It is used at a charging molar ratio within the range of /90 to 90/10. In normal cases, a polymer having a composition ratio almost the same as the ratio of the nine raw materials used is obtained. During production, 1. In the usual case, 2,3-dihydroplant 2.3-dihydro-2
, 2-dimethylfuran are charged into the reactor at the same time,
You can also prepare one first and then the other. K like this, unit! A polymer having two kinds of tetrahydrofuran skeletons represented by the unit (1) and (2) is obtained. The polymer may be a random polymer or a block polymer. The ratio of tetrahytomifuran units (unit I) to 2,2-dimethyltetrahydrofuran units (unit n) in the obtained polymer is 1, which can be easily determined using, for example, a nuclear magnetic resonance apparatus.

Specific examples of initiators used in producing the resin of the present invention include protonic acids such as hydroiodic acid, metal oxides such as chromium oxide and molybdenum oxide, iodine, bromine,
No-rogens such as iodine bromide.

Boron trifluoride, phosphorus trifluoride ether complex.

aluminum chloride, aluminum bromide, titanium tetrachloride,
Metal halides such as titanium tetrabromide, tin tetrachloride, iron trichloride, organometallic compounds such as ethylaluminum dichloride, diethylaluminum dichloride, diethylaluminum bromide, diethylzinc, triphenylmethylantimony hexachloride, triphenyl Examples include carbonium ion salts such as methyltin pentachloride. The initiator is 2
．． It is used in a range of 0.01 mol to 10 mol, preferably in a range of 0.05 mol to 2 mol, with respect to the 3-dihydro 7-ran brocade conductor.

The polymerization temperature is -200°C to 100°C.

Preferably, the temperature is selected from the range of -100°C to 50°C. The polymerization reaction is usually carried out using nitrogen or argon.

It is carried out under an inert gas atmosphere such as helium.

benzene, although the polymerization can also be carried out in the absence of a solvent.

Aromatic hydrocarbons such as toluene, xylene, and mesitylene, aliphatic hydrocarbons such as heptane, hexane, and octane, alicyclic member hydrogens such as cyclohexane and cyclooctane, and halogenated carbons such as methylene chloride, chloroform, and tetrachloroethylene. It is preferable to carry out the reaction in the presence of a solvent such as hydrogen in terms of removal of reaction heat and ease of handling of the resulting polymer.

In addition to the above solvents, diethyl ether, dibutyl ether, dioctyl ether, ethylene glycol dimethyl ether may be used depending on the initiator.

Ethers such as diethylene glycol, diethyl ether, and tetrahydrofuran, and methyl acetate.

The polymerization reaction may be carried out more efficiently by appropriately coexisting ketones such as ethyl acetate, isopropyl acetate, methylnato benzoate, acetone, methyl ethyl ketone, methyl isobutyl ketone, and the like. The reaction time is usually selected from a range of 1 second to 100 hours. After reaching the desired degree of polymerization, the reaction is stopped by a known method, and the resulting polymer is isolated and purified.

The resin of the present invention is a unit! and percentage of unit ■.

Alternatively, it usually has a glass transition temperature of 120° C. or higher, preferably 125° C. or higher, and has high heat resistance, although it varies depending on the molecule. As the number of units (■) increases, the glass transition temperature tends to increase.In addition, as the proportion of units (H) increases, the water absorption rate of the molded product obtained from the polymer also decreases. However, since the mechanical strength also tends to decrease, the optimum combination of unit I and unit ■ is selected depending on the application.

This is a raw material compound used in the present invention.

2.3-Dihydrofuran is produced by the dehydration reaction of 2-hydroxytetrahydrofuran or by 1.
It can be produced by dehydration and dehydrogenation of 4-butanediol. Also, 2,3-dihydro-2,2-
Dimethylfuran is produced by the dehydration reaction of 2,2-dimethyl-5-hydroxytetrahydrofuran, or by the dehydration reaction of 2-methyl-5-hydroxytetrahydrofuran.
It is produced by dehydration and dehydrogenation of 2,5-bentanediol.

As mentioned above, it is already known that poly(2,3-tetrahydrofuran diyl) can be obtained by cationically polymerizing 2,3-dihydrofuran. For example, Journal of Chemical 5oc
iety.

1954, 3766 pages, Polymer Journal
al l vol. 6 p. 415 (1984) or
Polymer Preprints Vol. 24, p. 317 (1983) describes cationic polymerization of 2,3-dihydrofuran and its derivatives. However, these prior documents.

Moreover, in any other known literature, there is no mention of the physical properties of molded articles derived from the obtained polymer. According to the studies of the present inventors, poly(2,
The molded product obtained from 3-tetrahydro7randiyl has sufficiently high mechanical properties such as 1 strength and 1 elastic modulus, has a relatively high glass transition temperature, is transparent, and has the potential to be industrially useful. It turns out that there is something. However, it has become clear that the molded product has a relatively high water absorption rate and is not necessarily suitable for applications requiring a low water absorption rate, such as optical applications such as lenses and diffraction gratings. .

In addition, the Journal of Chemica mentioned above
l 5ociety.

1954, p. 3766, 2,3-dihydro-2,2
- Polymers by cationic polymerization of dimethylfuran are also disclosed. However, in this case as well, no physical properties other than the softening temperature of the resulting polymer are mentioned.

2,3-dihydrofuran and 2,3-dihydro- of the present invention
There has been no description of a copolymer obtained by copolymerizing 2,2-dimethylfuran, and it is a novel polymer. A molded article obtained from a polymer obtained by copolymerizing 2,3-dihydrofuran and 2,3-dihydro-2,2-dimethylfuran has sufficient mechanical strength.

There has been no description or even suggestion that the water absorption rate is low. 2,3-dihydro-2,2
- Molded articles obtained from polymers obtained by cationic polymerization of dimethylfuran have low mechanical properties, and 2,3-dihydrofuran and 2,3-dihydro-2,2-dimethyl For the first time, by copolymerizing furan in an appropriate ratio.

Each molded product with high mechanical strength and low water absorption is obtained.

The resin molding of the present invention can be carried out by conventional melt molding or by conventional melt molding.

It can be processed into various molded products by cast molding using an appropriate solvent.

As can be seen from the examples below, the resin of the present invention has a very small photoelastic coefficient, and a molded article with small optical distortion can be obtained.

Taking advantage of the above-mentioned excellent features, the heat-resistant transparent resin of the present invention can be used in the following applications: Alternative 4) Various lenses for glasses, cameras, loupes, projection televisions, etc. 5) Optical disk player pickups, spectroscopic elements.

Diffraction gratings such as optical low-pass filters 6) Various optical elements such as prisms, optical waveguides, beam scatterers, etc. 7) Covers for automobile headlamps, rear lamps, etc. 8) Substrates for optical recording media such as optical disks and optical cards [Example] ] The present invention will be explained in more detail with reference to Examples below.

Note that the physical property values were measured according to the following method.

(2) Number average molecular weight and molecular weight distribution: Determined by GPC (polystyrene equivalent) K.

(2) Glass transition temperature: Measured by differential thermal analysis (in nitrogen, heating rate 10°C/min).

(i) Total light transmittance: Measured by a method according to ASTM D1003 on a plate formed to a thickness of 1 inch by heat pressing.

■ Photoelastic coefficient: Heat press Nyonyo 100 ■ × 20 cod × 1
(1) Soejima et al.'s method using a helium-neon laser as a light source (Komunshi Experimental Science, edited by the Polymer Experimental Science Editorial Committee of the Society of Polymer Science, Vol. 1O, p. 296 (1983))
) Kyoritsu Shuppan) Obtained in accordance with K.

■ Bending strength and bending elastic modulus: JIS for plates formed by heat press 100 x 20 ■XIIIK
Measured by a method similar to K7203.

(2) Saturated water absorption rate = Measured by determining the rate of weight increase when no time change in weight increase due to water absorption was observed in distilled water at 23°C.

Example 1 A glass container equipped with a stirring device and having a content of 9 IJ was sufficiently replaced with dry nitrogen, and then dehydrated toluene was added to the container.
．． 5j was charged, boron trifluoride was blown into the mixture until the concentration was 0.01 mol/J, and the mixture was cooled to -78°C.

1. Dehydrated 2,3-dihydrofuran was added to the solution while stirring.
A mixture of 9f (0.28 mol) and 2,3-dihydro-2,2-dimethylfuran 81f (0.83 mol) was gradually added over 20 minutes.

After continuing the reaction at this temperature for 48 hours, 1Qm# of a 1N methanol solution of aqueous ammonia was added to stop the polymerization.

Next, the solution was added dropwise into methanol 104, and a white product 409 was obtained by reprecipitation according to a conventional method. Number average molecular weight of the product tt gel permeation chromatography K! When determined by illumination, it was 61,300 in terms of polystyrene, and the molecular weight distribution was 1.69.

The product was dissolved in deuterated chloroform, and 5 Q Q M
Hz'HNMRK was measured at 1.2 pP.
ma 1.999m%3 and 8 pprn, area ratios are 48% and 34%, respectively.

Three absorptions of 18% were seen. Regarding these absorptions, absorption of 1.2 ppm is caused by the protons of the methyl group, absorption of 3.8 ppm is caused by the protons of methine and methylene adjacent to oxygen, and absorption of 1.9 ppm is caused by the protons of the remaining methine and methylene groups. peaks can be attached.

The infrared absorption spectrum of a cast film from a tetrahydrofuran solution of the product shows wave numbers of 910 cm and 1060 crR, as in the case of 2,3-dihydrofuran and U2,3-dihydro-2,2-dimethylfuran.
-” absorption due to -C-O-C- is observed, and 1
The absorption due to the double bond at 630 cm had disappeared.

From these results, the product has the following repeating unit 130
It was confirmed that the polymer represented by molti and repeating units [170 mol] was polymerized at the double bond in the ring without opening the five-membered ring, and the polymer obtained from the polymer The physical properties of the molded product are summarized in Table 1.

Example 2 In Example 1, instead of performing the reaction at -78°C for 48 hours, the reaction was performed at -50°C for 1 hour, and 2.3-
42 t (o, 6 mmol) and 58 t of dihydrofuran and 2,3-dihydro-2,2-dimethylfuran, respectively.
Polymerization was carried out under the same conditions as in Example 1 except that (0.60 mol) was charged. 95t of white product was obtained,
As a result of analysis by IH-NMR, the product was a polymer represented by the following repeating units of 148 molti and 1152 molti. The physical properties of the polymer and the molded article obtained are summarized in Table 1.

Example 3 In Example 1, methylene chloride was used instead of toluene, and 2,3-dihydrofuran and 2,3-dihydro-2
Polymerization was carried out under the same conditions as in Example 1, except that 68 t (0.97 mol) and 32 t (0.33 mol) of 2-dimethylfuran were charged, respectively. A white product of 63F was obtained, and analysis by 'H-NmRK confirmed that the core product was a polymer represented by the following repeating units of 173 mol and 127 mol.

The physical properties of the polymer and nine molded articles obtained from the polymer are summarized in Table 1.

Example 4 Except for charging 17 m of xane solution and charging 52 f (0.74 mol) and 48 t (0.49 mol) of 2.3-dihydrofuran and 2.3-dihydro-2,2-dimethylfuran, respectively. Polymerization was carried out under the same conditions as in Example ff1J1. A white product of 39f was obtained 1)1
-As a result of NMR analysis, the product is the following repeating unit! It was confirmed that the polymer was expressed by 60 moles and units [40 moles].

princess Table 1 summarizes their feelings of sadness.

Comparative Example 1 The same procedure as in Example 1 was carried out except that 1009 (1.0 mol) of 2,3-dihydro-2,2-dimethylfuran was prepared and 3-dihydrofuran was not prepared! pJl
Polymerization was carried out under the same conditions. A white product of 43j' was obtained, and as a result of analysis by 11(-NMR), it was confirmed that it was a polymer represented by a primary repeating unit.

Comparative Example 2 In Example 1, s2.3-dihydrofuran was converted to 93F (
Polymerization was carried out under the same conditions as in Example 1, except that 2,3-dihydro-2,2-dimethylfuran was not charged. A white product of 379 was obtained, and 1) 1-NMR confirmed that it was a polymer represented by the following repeating unit. 1 item book'1'a 1, number C ri 2゜↓
Bottom margin [Effect of the invention] The present invention provides a resin that has high heat resistance and sufficiently large mechanical properties, has a relatively low water absorption rate, and provides a transparent molded product with low optical distortion. be done.

This resin can be used in a variety of applications where transparency is required.

Patent applicant: RiRashi Co., Ltd.

Claims (1)

[Scope of Claims] 1) Consisting essentially of two types of tetrahydrofuran skeletons represented by the following repeating units, I and repeating unit II, each of which contains 10 mol% to 9 mol% of unit I and unit II.
A heat-resistant transparent resin which is present in an amount of 0 mol % and has a molecular weight within a range of 5,000 to 200,000 in terms of polystyrene equivalent number average molecular weight when measured by gel permeation chromatography. ▲There are mathematical formulas, chemical formulas, tables, etc.▼... I 2) I and II are each 25 mol% to 75 mol%
The heat-resistant transparent resin according to claim 1, which is within the range of.