JPS58113214A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a highly transparent resin composition of excellent heat and moisture absorption resistance, having a moderate refractive index, by carrying out a copolymerization, in the presence of a catalyst, of each specific amount of cyclohexyl methacrylate, styrene, methacrylic acid etc. CONSTITUTION:The objective resin composition of a refractive index 1.51- 1.57 can be obtained by mixing the following three components, i.e. (A) 20- 80wt% of cyclohexyl methacrylate, (B) 0.5-70wt% of styrene, and (C) 1.5- 20wt% of at least one sort of compound selected from methacrylic acid, acrylic acid, methacrylamide and acrylamide, incorporating the resultant mixture with a catalyst (e.g. t-butyl peroxy-2-ethyl hexanoate) and homogeneously stirring followed by carrying out a copolymerization. USE:Optical plastics, lenses for glasses, cameras, automobile lamps, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resin composition that is excellent in heat resistance and scuffing resistance, and has a moderate refractive index and excellent transparency.

In recent years, flexible plastics have been used to make lenses for mirrors, cameras, and automobile lamps, as well as inorganic materials with special shapes that are difficult to process, and Fresnel lenses. Demand for optical materials such as lenses, wrench accessories, i-ikp prism matte lenses, etc. has been expanding.

This is because the light weight and excellent workability of plastics has been recognized, and plastic materials have become widely used in the field of optical materials from the viewpoint of energy and labor savings (cost reductions).

However, there are some difficulties in using plastic materials, such as heat resistance, moisture absorption, and g/! It is recognized that there is a need to improve performance without further modification in terms of properties, mechanical properties, etc.

Typical transparent resins currently used as such light-emitting materials include polymethyl methacrylate, polycyclohexyl methacrylate, CR-noodles, POIF carbonate, and polystyrene, each of which has a viscosity of 1.41% at room temperature.
Because it has a refractive index of 1.51, IJo, 1.58, and 1.19.

As mentioned above, this type of resin has a refractive index of 1.41-
1. il () low refractive index region, 1.58-1.511
Most of the materials exhibit a refractive index in one of the high refractive index regions, and it is desired to develop an optical material having a refractive index in a range between the two.

Such an intermediate region OJ can also be obtained by copolymerization of styrene and methyl methacrylate, for example. However, in this resin composition, polymethyl methacrylate inherently has high hygroscopicity. As a result, under severe humidity conditions, resin moldings subjected to precision IFK processing may easily deform or cause fluctuations in the refractive index, which may affect optical performance. It is desired to develop a resin with less carbon and AII properties.

On the other hand, the heat deformation temperature of plastic ivy is much lower than that of inorganic materials, and it is no exaggeration to say that the use of plastics is expanding as the resistance to 0 and 1 is increasing.

In this way, studies have been made to improve heat resistance from the 1m point, and for example, in the specification of d1 German Public H Patent No. 223@8,
Siku-aq-syl metatarylate and styrene and anhydride! A Rhein 1mO copolymer has been proposed.

Addition of maleic anhydride certainly improves heat deformation resistance, but if polymerization is completed in a reactor using a heavy metal method, a copolymer with a non-uniform composition will be produced. A resin with the desired transparency cannot be obtained, and there are problems in using it as an optical material.

In view of the current situation, the present inventors have developed a method for producing a resin composition that has a refractive index of 1.51 to 1.57, has high transparency, moisture absorption resistance, and heat resistance, and can be used as an optical material. As a result of extensive research, we have selected from a group of water-soluble monomers consisting of V-terhexyl methacrylate and styrene as the main components, and methacrylic acid, acrylic methacrylic acid, and acrylamide. It was discovered that a copolymer resin composition can have extremely excellent properties by mixing monomers with a suitable weight range and copolymerizing them. Ta.

That is, the present invention provides (A) cyclohexyl methacrylate) 20 to 80 weight (9) styrene O,S to 70 weight (cut) methacrylic acid, acrylic acid, methacrylic acid,
A refractive index of 1.51 to 1.5% obtained by copolymerizing a mixture of at least one acrylamide of 1.1 to 20% by weight in the presence of a polymerization catalyst. This is a resin composition of s7.

%, water-soluble monomers are added as a copolymer composition to improve heat resistance, but the 1 lil property is sufficiently low, the heat resistance is sufficiently improved, and the beautiful resin composition is free from cloudiness and cloudiness. It is worth noting that things can be obtained.

Among the main monomers of the water-soluble monomer group, methacrylic acid and acrylic acid show equivalent properties and can be arbitrarily resolved into cyclohexyl methacrylate, styrene monomer mixture,
Produces a transparent copolymer.

As the mixing ratio of these unsaturated carboxylic acids increases, the heat resistance of the resulting copolymer improves.

On the other hand, as the mixing ratio of unsaturated carboxylic acid increases, the am property of the obtained copolymer increases little by little, but if the amount of unsaturated carboxylic acid added is less than The resulting copolymer exhibits sufficiently low IlIl property.

By the way, when a copolymer body containing an unsaturated carboxylic acid is thermally formed, a dehydration reaction occurs between adjacent carboxyl groups, and bubbles due to water vapor may be generated inside the laminated resin.

The #iI phenomenon caused by ζO becomes more pronounced as the amount of unsaturated carboxylic acid added increases, but as long as the amount of unsaturated carboxylic acid added is 6 weight or less, there is virtually no problem and heat formation is possible. It is.

However, if the amount of unsaturated carboxylic acid added is less than 12% by weight, a heating molding machine equipped with a vent hole is used.
It is preferable to prepare the product without removing the volatile components generated.

However, if the amount of unsaturated carboxylic acid added is 12 weight or more, heat forming is performed), but rather it is preferable to carry out cast iron polymerization into the shape to be layered.

On the other hand, regarding the monomers in this class II monomer group, methacrylic acid and acrylamide O unsaturated amide,
Cyclohexyl methacrylate, styrene monomer mixture 1
Since there is a limit to the solubility of 1 to 11, it is preferable to use 0, which is less than 10% by weight, but even then, a sufficient improvement in heat resistance can be expected.

These methano 9 contain acids, acrylic acid, methacrylamide,
Monomers in the water-soluble monomer group consisting of atarylamide may be used alone or in combination, and in the sense of improving thermal decomposition, acrylic It is preferable to contain a small amount of an acrylic monomer such as at or acryl-ad.

Therefore, as the content of hexyl methacrylate increases, the mechanical strength of the resulting Kyodo metal body decreases. Target strength aS
If the tatami is used, the content of cyclohexyl methacrylate should be less than or equal to 100% by weight, preferably 100% by weight. Best used below.

However, it goes without saying that the monomer eIlll gold composition is generally determined by the refractive index of the resulting resin.

The refractive index of the resulting resin composition can be approximated by the sum of the product of the refractive index of the homopolymer of the constituent monomers and its composition ratio.

Therefore, it is preferable that the mixed composition of the monomers be selected based on a comprehensive evaluation of heat resistance, mechanical strength, refractive index, and hygroscopicity.

Next, we investigated the impurities contained in the monocyclohexyl methacrylate monomer and the heat deformation resistance of the resulting resin composition.
It contains about 0.5 weight of cyclohexanol, which is purified and transferred to Shifutan to reduce the content of Φnanol to 0.0.
The heat deformation temperature of the resin obtained by polymerizing monomers with a weight of 1% or less was improved by about 4°C.

Therefore, it has been found that when heat resistance is required, it is better to subject silica methacrylate to such a pretreatment.

In addition to cyclohexyl methacrylate, styrene, methacrylic acid, acrylic acid, methacrylamide, and acrylamide, the monomers to be copolymerized include acrylic esters and methacrylates in an amount not exceeding 0.1 weight, preferably not exceeding 5 weight. Acid esters, α-methylstyrene, acrylonitrile, and methacrylic ax) may also be blended.

Hereinafter, the present invention will be specifically explained based on examples. In addition, in 1 in Examples, parts represent parts by weight.

Also, the heat resistance deformation temperature 1L Hirom 8TM-Di48, the maximum weight is the load ti A8TM-D-7H-131? , Shokuko Matsun Anti JI8-z-stzs, 11 water rate is A
8TM-D-! 170-+I3,) k door-index

Example 1 The content of cyclohexanol, an impurity, was reduced to less than 1 pp'xa by rectification. Diterhexyl methacrylate (hereinafter referred to as lll1 cyclohexyl methacrylate) was 47.1%, and styrene was 47.1%. s part, methanol & sm, tert-butyl peroxy S/type etherhexanoate 04i11 as a heavy metal initiator, 0.2 part of octyl mercaptan as a chain transfer agent, and 0.2 part of a mold release agent.
005 parts of fireflies, stirred uniformly, and injecting the composition into a cell formed by two tempered glass plates facing each other at a distance of 1 m and sealed with a GV vinyl chloride gasket,
It was immersed in warm water at 65° C. for 34 hours to polymerize and harden. Next, heat treatment was performed for 3 hours in an air heating furnace at 110°C,
Complete polymerization and form a circle. After cooling, the cell was removed to obtain a colorless and transparent resin plate with a thickness of about 1 m. This was used as a test piece for physical property II.
I made a determination. The results are as shown in Table IK.
It had excellent performance as an optical material.

Table 1 Next, the resulting resin plate was crushed and molded at 250°C using an extrusion molding machine with a vent hole, but no foaming was observed in the molded product.

Example 2 4s parts of purified cyclohexyl methacrylate, 4 parts of styrene
5 parts of methacrylic and 0 parts of tert-butyl peroxy 2-ethylhexanoate as a polymerization initiator.
After adding 4 parts of octyl mercaptan as a chain transfer agent and stirring uniformly, the composition was polymerized, except that polyester films were used on the surfaces of two opposing glass plates. The reaction was carried out under the same polymerization conditions as above, and a colorless and transparent resin plate was obtained. The physical properties were measured using this as a test piece, and the results are shown in Table 2.

Next, after pulverizing the resin plate obtained here, extrusion molding with a vent hole was performed at ms''ess·°C, but no foaming was observed in the molded product.

Example 1 All polymerization conditions were the same as in Example except that 42.5 parts of purified cyclohexyl methacrylate, 43.5 parts of styrene, and 15 parts of methacrylic acid were mixed, and 0.2 part of lauryl peroxide was added as a polymerization initiator. A colorless and transparent resin plate without any reaction was obtained. This was used as a test piece with physical properties of 0 all
The results of the determination are shown in Table 1.

Table 3 Example 4 45 parts of purified cyclohexyl methacrylate, 4 parts of styrene
Part S and 10 parts of acrylic acid were mixed, and the same catalyst and reaction conditions were used as in Example 1 to obtain a colorless and transparent resin plate. The physical properties were measured using this as a test piece, and the results are shown in Table 4.
In copolymerizing a composition consisting of 5 parts and 8 parts of methacrylic acid, a transparent resin plate was obtained by using the same catalyst and polymerization conditions as in Example 1.

The physical properties were measured using this as a test piece, and the results are as shown in Table SK.

Implementation side number: 49 parts of purified fluorohexyl methacrylate, 4 parts of styrene
In copolymerizing a composition consisting of Part Ia and 2 parts of acrylic acid, a transparent side plate was obtained using the same catalyst and polymerization conditions as in Example 1. The physical properties were measured using this as a test piece, and the results are shown in Table IK.

Example 1 49 parts of purified cyclohexyl methacrylate, 4 parts of styrene
In copolymerizing a composition consisting of 9 parts of methacrylamide and 2 parts of methacrylamide, the catalyst and polymerization conditions were all the same as in Example 1 to obtain a transparent residue resin plate.The physical properties were measured using this as a test piece. Company, the notice shown in Table SK.

Example 8 Purified Schiff-hexyl methacrylate 47. In copolymerizing a composition consisting of part s, 47.5 parts of styrene, 15 parts of methacrylic acid, and 1 part of acrylic acid, the same catalyst and polymerization conditions as in Example 1 were used to obtain a transparent resin plate. Using this as a test piece, the physical properties were determined to be 0. The results are as shown in Table 5. A transparent resin plate was obtained by copolymerizing a composition consisting of 1 part of acrylamide using the same catalyst and polymerization conditions as in Example 1. The physical properties were measured using this as a test piece, and the results were clearly inaccurate.

Comparative Example 1 After polymerizing 110 parts of purified sulfur methacrylate, a transparent resin plate without ζ was obtained using the same catalyst and polymerization conditions as in Example 1.

Using this as a test piece, the physical properties were measured at tIPζ, and as a result,
The strength of the piece was tso Kg/ai and it was extremely brittle, and the heat deformation temperature was as low as @4°C.

Comparative example = 50 parts of purified cyclohexyl methacrylate, styrene g
In copolymerizing the composition consisting of part o, all catalysts and polymerization conditions were used in the same manner as in Example 1 to obtain a transparent resin plate. As a result of measuring the physical properties using this as a test piece, it was found that the heat resistance deformation temperature was as low as fd°C.

Comparative Example 3 Purified cyclohexyl methacrylate a & parts, styrene I
A transparent resin plate was obtained by copolymerizing a composition consisting of s@ and 980 parts of methacrylic using the same VC mixture, catalyst, and polymerization conditions as in Example 1.

Using this as a test piece, we measured its physical properties and found that the bending strength was sio Kg/ai, and the heat distortion temperature expansion was 130.
Although the temperature was satisfactory at 5°C, the water absorption rate was high at 2.51.

Comparative Example 4 45 parts of purified cyclohexyl methacrylate, 4 parts of methylef
When a composition consisting of 5 parts of maleic anhydride and 10 parts of maleic anhydride was copolymerized using the same method, catalyst, and polymerization conditions as in Example 1, the resulting resin plate was cloudy and could not be fully exposed to light. The transmittance was as low as 5at-.

Comparative Example 2 The polymerization inhibitor (methoquinone) contained in commercially available cyclohexyl methacrylate was removed by simple distillation, and the resulting fraction (cyclohexyl methacrylate) was analyzed. Detected 0 When copolymerizing a composition consisting of 745 parts of cyclohexyl methacrylate AS#Styrene and 10 parts of methacrylic #, all the paper, catalyst and polymerization conditions were carried out in the same manner as in Example Yuki. Got the board. When the heat distortion temperature was measured using this as a test piece, it was 1.SC, which was 4°C 1! compared to the case where purified cyclohexyl methacrylate was used (Example 1). 90 Patent Applicant Asahi Kasei Kogyo Co., Ltd. Procedural Amendment (Voluntary) February 1982 Commissioner of the Japan Patent Office Haruki Shimada L. Case Indication 1984 Patent Application No. 2098f
iO No. 2 Name of the invention Resin composition a Relationship with the case of the person making the amendment Patent applicant 1-2-6-Tun Dojimahama, Kita-ku, Osaka-shi, Osaka Prefecture Subject of amendment ll1i The "detailed description of the invention" in Book IIA - Contents of amendment (1) [150 to 4/
am"J is corrected to [11001147ca month.

(2) "Example 1" on page 16, line 14 is corrected to "Example 2 JK.

(3) “Example 1” on page 17, line 3 of the same page was replaced with “Example 2.”
JK correct.

that's all 124-

Claims (1)

[Scope of Claims] (4) Shita ■ to middle syl metatarylate - weight one (
1) Styrene e, i - weight - (0 methacrylic acid, acrylic acid, methacrylic acid, atta 9 to amide) of 1.5 to 1.5 to 1.5 weight - heavy metal catalyst A resin composition having a refractive index of 1.il-1,17 obtained by co-electrolytic etching in the presence of