JPH01254726A - Thermosetting resin composition and molding thereof - Google Patents

Abstract

PURPOSE:To obtain the title cokpositionfree from developing volume change, strain, sink marks, cracks, etc., when cured, by incorporating a specific urethane (meth)acrylate-contg. radically polymerizable vinyl monomer with each specified amount of an organic peroxide and specific reaction product. CONSTITUTION:The objective thermosetting resin composition can be obtained by incorporating (A) 100 pts.wt. of a solution of a radically polymerizable vinyl monomer containing >=30wt.% of urethane (meth)acrylate produced by reaction of a diisocyanate compound, a dihydroxy organic compound and a hydroxyl group-contg. (meth)acrylate in succession is incorporated with (B) 0.01-10 pts.wt. of an organic peroxide and (C) 0.1-10 pts.wt. of a reaction product from an acrylic compound and a diisocyanate compound. Curing of said composition in a mold at 30-200 deg.C will produce, in high yield, a transparent, optically isotropic molded product of uniform thickness suitable as an optical card, etc.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a thermosetting resin composition capable of producing transparent molded products without volume change, distortion, sink marks, cracks, etc. during curing; and its molding method. These are used for optical cards, optical disks, etc.

[Prior art and problems to be solved by the invention] Conventionally,
By adding a crosslinking agent to a radically polymerizable vinyl monomer and curing it using a radical polymerization initiator,
BACKGROUND OF THE INVENTION It is well known to produce molded articles of thermosetting resins. For example, molded articles of unsaturated polyester resin are manufactured by curing the resin using a radical polymerization initiator. Furthermore, JP-A No. 61-207408 describes a method for obtaining a disk substrate by mixing a polyfunctional monomer in styrene and subjecting it to radical formation, and the amount of the polyfunctional monomer added is It is disclosed that if the ratio exceeds 30 wt.6, the shrinkage becomes large and it is impossible to obtain an optically isotropic substrate.

When manufacturing such transparent thermosetting resin molded products, one of the major problems in improving the molding accuracy is that the volume change (volume shrinkage) of the resin material during curing is large. Distortion, sink marks, cracks, and other phenomena that occur with

In order to prevent the occurrence of these phenomena, various methods are being used to reduce the shrinkage of thermosetting resins during curing.

For example, for unsaturated polyester resins, a method of blending a thermoplastic resin (see British Patent No. 936,351) has been proposed.

However, this method has limitations in terms of compatibility between the thermosetting resin material and the thermoplastic resin, and 11? Problems arise in that the physical properties of the cured product change later or phase separation occurs.

It is also known that the effect of volume shrinkage during curing can be reduced depending on the type of crosslinking agent, but this effect is generally small.

It is also known that the influence of volume shrinkage during curing can be reduced depending on conditions such as curing speed, curing temperature, and amount of initiator. That is, by slowing down the curing speed by slowing down the thermal decomposition of the initiator, by lowering the curing temperature to avoid rapid decomposition of the initiator, and by reducing the amount of initiator, radical curing is prevented. By molding, the effect of volumetric shrinkage during curing can be reduced. However, the effect is not sufficient.

On the other hand, when a thermosetting resin is molded into a plate shape by a casting method, the molded product shrinks in the vertical and lateral directions. At this time, if the molded product is a thick plate, sink marks due to shrinkage do not occur much.

However, when the molded product is a thin plate with a thickness of 1 mm or less, lateral shrinkage becomes large and sink marks occur, making it extremely difficult to mold a thin plate with a uniform thickness with a good yield.

Therefore, an object of the present invention is to provide a thermosetting resin composition that has extremely little effect on volume change during curing and that can produce transparent and optically isotropic molded products that are free from distortion, sink marks, cracks, etc. Our goal is to provide the following.

Another object of the present invention is to form a thermosetting resin composition that has the above-mentioned properties and can be molded with a high yield into a thin plate having a thickness of 1 mm or less and having no distortion, sink marks, cracks, etc. The purpose is to provide a method for forming objects.

[Means to Solve the Problem] As a result of intensive research, the inventors of the woodworks have found ways to reduce the amount of initiator and to Completely different from the conventional means mentioned above, which lowers the curing temperature to slow down the rate of thermal decomposition of the initiator, the amount of initiator can be halved by adding a specific reaction product to a specific radically polymerizable vinyl hexamer solution. By molding under short time conditions,
It has been found that a thin plate having a thickness of 1 mm or less can be obtained with a good yield and has a uniform thickness and is completely free from so-called sink marks.

The present invention was made based on the above findings.

(a) By sequentially reacting the following three components [1] to [3], 1
1) To 100 parts by weight of a radically polymerizable vinyl monomer solution containing urethane methacrylate or urethane acrylate in an amount of 3QBIH or more, add hydroxy group-containing methacrylate or hydroxy group-containing acrylate (b) organic 0.01 to 10 parts by weight of peroxide (c) Reaction product of the following [1] and [2] ■ Acrylic compound ■ Thermosetting resin obtained by adding 0.1 to 10 parts by weight of diisocyanate compound A composition is provided.

The present invention also provides a method for molding the thermosetting resin composition, which comprises curing the thermosetting resin composition in a mold at a temperature range of 30 to 200°C. It provides:

Hereinafter, the thermosetting resin composition of the invention will be described in detail.

Examples of the radically polymerizable vinyl monomer that constitutes component (a) of the thermosetting resin composition of the present invention include styrene, vinylpyridine, vinylcarbazole, butadiene,
Acrylates such as acrylonitrile, methyl acrylate, ethyl acrylate, isopropyl acrylate, alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate,
Examples include dialkyl fumarate esters such as dicyclohexyl fumarate and diynebutyl fumarate.

Further, urethane methacrylate or urethane acrylate, which is another component of component (a) of the present invention, can be obtained as follows.

First, (1) a diisocyanate compound and (2) a dihydroxy organic compound are reacted.

The above diisocyanate compound (1) is preferably a so-called aliphatic diincyanate compound having an NGO group on an aliphatic carbon, such as xylylene diisocyanate or hexamethylene diisocyanate I.

In addition, as the dihydroxy organic compound mentioned above, bisphenol A, aromatic halokene am of bisphenol A, etc.
body, bisphenol S, hydroquinone, ethylene glycol, furopylene gellicol, bentanediol,
Hexanediol.

1.4-dihydroxycyclohexane, butanediol, hydroxyphenethyl alcohol.

1.2-Benzenedimetatool, l, 3-benzenedimetatool, l, 4-benzenedimetatool, bis(4-
Examples include hydroxyphenyl)methane, bis(2-hydroxyphenyl)methane, and bis(4-hydroquinecyclohexyl)propane.

The amount of the above diisocyanate compound and dihydroxy organic compound is NCO group 10H group (molar ratio) = 1
The range is preferably from 1.5 to 3, particularly from 1.5 to 3.

Next, the reaction product of (1) the diisocyanate compound and (2) the dihydroxy organic compound described above is reacted with (1) the hydroxy group-containing methacrylate or hydroxy group-containing acrylate to obtain urethane methacrylate or urethane acrylate.

The hydroxyl group-containing methacrylates or hydroxyl group-containing acrylates include 2-hydroxyethyl methacrylate-1., 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 12-hydroxybutyl methacrylate, and 3-hydroxybutyl methacrylate.

4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 6-hydroxyethyl acrylate, 4-hydroxycyclohexyl methacrylate, 4-hydroxyphenyl methacrylate, 3-hydroxyphenyl methacrylate, diethylene glycol monomethacrylate, triethylene glycol monomethacrylate, dipropylene Glycol monomethacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxypropyl acrylate, 3-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, 5-
Hydroxypentyl acrylate, 6-hydroxyhexyl acrylate, 4-hydroxycyclohexyl acrylate, 4-hydroxypheco acrylate, 3-
Hydroxyphenylacryle-1.

Examples include diethylene glycol monoacrylate, triethylene glycol monoacrylate, and diprobylene glycol monoacrylate.

The reaction between the reaction product of the above compound (1) and the compound (2) and the compound (2) above causes the hydroxyl group of the compound (2) to react.

This is to react with the excess NGO group in the reaction between the compound (1) and the compound (2), and the amount of the compound (1) used is NCO group in the reactant/OH group in the compound (molar ratio) = 0.5 ~
2.0.4'F is preferably in the range of 0.8 to 1.2.

All of the above reactions are generally carried out at a temperature of 10°C to 10°C, preferably 20°C to 70°C. Also,
A catalyst can be used in the reaction to speed up the reaction rate. Such catalysts include organotin compounds such as dibutyltin dilaurate.

Catalysts that generally promote the urethane reaction, such as dibutyltin dioctanoate, organic zinc, and the like, can be used, and the amount used is preferably about 10 to 200 P, P, 11- for the entire reaction system. In addition, as a reaction solvent, (a) of the present invention is used.
As the radically polymerizable vinyl monomer which is a constituent component of the component, the same ones as those exemplified above can be used.

The radically polymerizable vinyl monomer solution which is component (a) of the present invention is prepared by adding urethane methacrylate or urethane acrylate obtained as described above to the radically polymerizable vinyl monomer in an amount of 30% by weight or more, preferably 60% by weight or less.
It was dissolved at a concentration of ~40% by weight. If the amount of urethane methacrylate or urethane acrylate is less than 30% by weight, the solution may separate into two layers, which is not preferable.

In the above-mentioned synthesis reaction of urethane methacrylate or urethane acrylate, when the radically polymerizable vinyl monomer is used as a reaction solvent, the obtained reaction solution is used as it is as the radically polymerizable vinyl monomer solution of component (a) of the present invention. can do. In this case, the solution of the radically polymerizable vinyl monomer (reaction solution) containing the obtained reaction product is usually 50 to 5000 cps.
It is a colorless and transparent solution with a moderate viscosity. This reaction solution can be diluted with the radically polymerizable vinyl monomer, if necessary.

Further, the organic peroxide which is the component (b) of the thermosetting resin composition of the present invention is preferably one represented by the following structural formula. At this time, other radical initiators can be used in combination.

CH3-C-0-0-C-R OH3 (In the above formula, R represents an alkyl group having 1 to 20 carbon atoms.) As the peroxide, the alkyl group represented by R in the above structural formula, ( , methyl group, isobutyl group (, isobutyl group, ■-methyl-pentyl group). Preferred peroxides include perbutyl A, perbutyl Pv, barbutyl 0, perbutyl L, perbutyl IB, etc. As for the structure, PerhexaC (
Peroxides sold under the trade name of Kuchiki Yushi (trade name) can be used.

2.Use 1i) of the pervolatized product is 0.01 to 10 parts by weight per 100 parts by weight of the radically polymerizable vinyl monomer solution.
Parts by weight, preferably 0.05 to 5 parts by weight, more preferably 0.2 to 3 parts by weight.

If the amount of peroxide is less than 0.011 iL parts, the polymerization rate will be low and a molded article with sufficient strength will not be obtained.

If the amount exceeds 10 parts by weight, the polymerization rate will be too high and cracks will occur in the molded product.

Component (c) in the present invention is effective in preventing sink marks during curing.

(The acrylic compound D is -OH group.

-Methacrylate containing -NH2 group, -OH group.

Acrylates containing -Nl (2 groups), specifically, methacrylates containing -OH groups and -NH2 groups include hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate.

3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, 3-aminopropyl methacrylate, 2-aminopropyl methacrylate, 4-aminobutyl methacrylate, ethylene glycol monomethacrylate, diethylene glycol monomethacrylate,
Examples include propylene glycol monomethacrylate and triethylene glycol monomethacrylate.

Examples of acrylates containing -OH and -NH2 groups include hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 3-hydroxybutyl acrylate, 3-aminopropyl acrylate, and ethylene glycol monoacrylate.

These include diethylene glycol monoacrylate, propylene glycol monoacrylate, 3-N-methylaminopropyl acrylate, and the like.

As the diisocyanate compound that can be used here, the same compound as the diisocyanate mentioned above can be used. In this reaction, -OH group/-NCO group, -amitsuno,%/-NCO
The molar ratio of the groups is from 0.2 to 0.8, preferably from 0.4 to 0,
React in the range of 6.

This reaction is carried out using the above-mentioned radically polymerizable vinyl monomer as a solvent, and optionally in the presence of the above-mentioned urethanization catalyst at a temperature of 20 to 100°C, preferably 40 to 70°C, and 0.1 to 3 A reaction product is obtained by reacting for a period of time. The obtained reaction product is not isolated,
Can be used as a solution.

Add the above reaction product to the solution containing the curing agent.
i to 10% by weight, preferably 0.3 to 5% by weight.

Subsequently, various surfactants can be added as release agents if necessary. JI) of surfactant is 10~
5000 p, p, m, preferably 50-2000
p, p, 111. amount is used.

The thermosetting resin composition of the present invention comprising the above-mentioned components (a), (b) and (c) can be molded, for example, as follows.

By heating and curing the thermosetting resin composition of the present invention in a mold such as a glass cell using a spacer made of soft polyvinyl chloride that is commonly used for molding this type of thermosetting resin, Molded products can be obtained.

The curing temperature varies depending on the decomposition rate of the peroxide used, but is usually 30 to 200°C, preferably 50 to 150°C.
It is. The curing time is not particularly limited, but is preferably 5 minutes to 5 hours, more preferably 30 minutes to 3 hours.

In addition, during curing, a peroxide decomposition catalyst such as a transition metal compound usually used in curing this type of thermosetting resin, such as organic acid Cobalt 342 or cobalt alcoholate, may also be used. can.

The molding method of the thermosetting resin composition of the present invention is not limited to the above-mentioned method, and the curing temperature and curing time conditions are set within the above ranges to form this type of 8-curable resin composition. It can be molded by a method conventionally used for molding.

Furthermore, by adding a photosensitizer or a photopolymerization initiator, the thermosetting resin composition of the present invention can be polymerized (cured) by light such as ultraviolet rays to obtain a molded article. It can also be cured by radiation, heat, etc., and molded products can be obtained.

[Example] Examples will be specifically shown below.

Example 1 2.5 g of methyl methacrylate was taken into a 5 g glass flask, and 6 moles (1165 g) of xylylene diisocyanate were dissolved therein.

Next, as a catalyst, dibutyltin dilaure-1.0.17g
Then, the reaction system was heated to 50°C.
Then, 3 moles of bisphenol A were gradually added. Since it generated heat, it was added while cooling, and after the addition was completed, the reaction was carried out at 60°C for 4 hours. Next, after cooling the reaction system to 45°C, 3 moles of 2-hydroxypropyl methacrylate was gradually added dropwise. 60" while cooling as it causes an exothermic reaction.
I kept it at C. After completion of the dropwise addition, the reaction was allowed to proceed for 4 hours. The obtained methyl methacrylate-1 solution is hereinafter referred to as dope.

Subsequently, the mixture was allowed to cool down to room temperature and then stored overnight. Next, 4-methoxyphenol'e? aM's 1000p, p, m,
Only added.

(1) To remove dust and the like from the solution, it was filtered under pressure through a filter with a hole diameter of 5p. Viscosity in solution is 560
It was cps. Dope with methyl methacrylate-1.
of methyl methacrylate/reaction product by adding
The ¥ ratio was set to 55/45.

To this dope, Perbutyl peroxide (manufactured by NOF Corporation) was added in an amount of 0.3% by weight based on the solution and dissolved.

Next, an additive for preventing sink marks was synthesized as follows.

84.9 g of xylylene diisocyanate was dissolved in 150 g of 4-methyl methacrylate for addition of Hikekarl, and then 20 mg of dibutyltin dilaurate was added and dissolved as a catalyst. Heating was performed with stirring, and when the temperature inside the reaction system reached 60°C, 2-
65.0 g of hydroxypropyl methacrylate was gradually added dropwise.

After completion of the dropwise addition, the mixture was allowed to react at the same temperature for 3 hours.

The additive for preventing sink marks obtained as described above was added in an amount of 1.5% by weight to the dope and dissolved.

Furthermore, as a release agent, 5% of phosphate ester additives were added.
00 P, P,! I+, added. 33mM of dope containing these additives was injected into a glass plate of 30cm x 30cm and 6mm thick with a polyvinyl chloride gasket attached, and after air was removed, the V was closed and the glass plate was fixed around it.

This glass cell was then heated at 80°C for 1 hour and at 120°C.
The material was heated and cured for 1 hour to form a plate. The board was a 0.4 mm homogeneous board with no sink marks that were observed in the past. Table 1 shows the physical properties of the plate.

Examples 2 to 3 In place of the peroxide barbutyl used in Example 1, 0.75% by weight of Perbutyl 0 was added to the dope obtained in the same manner as in Example 1. C to 0
．． Example it--Repeated except that 3ifi% was used.

The obtained board had good uniformity with no sink marks. The results are shown in Table 1.

Example 4 In the dope obtained in the same manner as in Example 1, 0.0% perbutyl PV was added instead of the peroxide perbutyl ether used in Example 1.
7% by weight was used, and the curing conditions were 70°C for 1 hour and 100'C! Example 1 was repeated except that the temperature was 120° C. for 1 hour. The physical properties of the obtained plate are
Shown in the table.

Examples 5, 6.7 The amount of the reaction product of 2-hydroxypropyl methacrylate and xylylene diisocyanate added to the dope obtained in Example 1 for preventing sink marks was changed from the amount of the reaction product of 2-hydroxypropyl methacrylate and xylylene diisocyanate used in Example 1
, 5% by weight, 0.5% by weight in Example 5, 3.0% by weight in Example 6, and 6.0% by weight in Example 7.
In addition, Example 1 was repeated. The results are shown in Table 2.

Comparative Example 1 Example 1 was repeated except that the reaction product of 2-hydroxypropyl methacrylate and xylylene diisocyanate for anti-sink mark IL was not added to the dope.

The results are shown in the m2 table.

(Left below) Examples 8 to 11 Instead of the reaction product of 2-hydroxypropyl methacrylate and xylylene diisocyanate used for sink mark prevention in Example 1, in Example 8 the molar ratio of hydroxyethyl methacrylate and xylylene diisocyanate was used. l:1
Example 9: 1.2% by weight of the reaction product of
In Example 1O, the reaction product of 2-hydroxypropyl acrylate and xylylene diisocyanate in a molar ratio of 1:1 was 1.5% by weight based on the dope, and in Example 1O, the reaction product of 2-hydroxypropyl acrylate and xylylene diisocyanate in a molar ratio of 1:1 was used. Example 1 except that 2.0% by weight of the product was added to the dope, and in Example 11, 2.5% by weight of a reaction product of 3-human mixibutyl methacrylate and xylylene diisocyanate in a molar ratio of 1:1 was added. repeated.

The evaluation of the obtained plates is shown in Table 3.

(Leaving space below) Examples 12 to 14 In Example 12, 2-hydroxypropyl methacrylate and xylylene diisocyanate were used in Example 12 in place of the reaction product of 1:1 molar ratio of 2-hydroxypropyl methacrylate and xylylene diisocyanate used to prevent sink marks. 1.3% by weight of the reaction product of a 1:1 molar ratio of methacrylate and hexamethylene diisocyanate; in Example I3, 2% of the reaction product of a 1:1 molar ratio of methacrylate and hexamethylene diisocyanate; Example 1 was repeated except that in Example 14, 1.2% by weight of a reaction product of 2-hydroxypropyl methacrylate and tolylene diisocyanate in a molar ratio of 1:1 was added. The physical properties of the obtained thin plate are
Shown in the table.

(Left below) Example 15 Example 1 was repeated except that 2.5 JJ of styrene monomer was used instead of 2.5 M of methyl methacrylate. The physical properties of the obtained plate are shown in Table 5.

Examples 16 to 18 In place of bisphenol A in Example 1, Example 1
6, 3 mol of 1,6-hexanediol, Example 17
Example 1 was repeated except that 3 moles of 1,4-butanediol were used, and in Example 18, 3 moles of bisphenol S were used. The physical properties of the obtained plate are shown in Table 5.

Examples 19 to 21 Instead of 2-hydroxypropyl methacrylate used for dope synthesis in Example 1, hydroxyethyl methacrylate was used in Example 19, 2-hydroxypropyl acrylate] was used in Example 20, and Example 21 So 3-
Example 1 was repeated except that hydroxybutyl methacrylate was used.

The physical properties of the obtained plate are shown in Table 5.

[Effects of the Invention] The thermosetting resin composition of the present invention makes it possible to obtain molded articles free from distortions, sink marks, cracks, etc. caused by changes in volume during curing.

Further, according to the method of molding a thermosetting resin of the present invention using the thermosetting resin composition of the present invention, the thickness is uniform and there is no occurrence of distortion, sink marks, cracks, etc., and the thickness is 1 mm or less. of? One plate can be molded with good yield.

These materials are suitably used for optical cards, disks, and the like.

Patent applicant: Ube Industries Co., Ltd.

Claims (2)

[Claims] (1) (a) To 100 parts by weight of a radically polymerizable vinyl monomer solution containing 30% by weight or more of urethane methacrylate or urethane acrylate obtained by sequentially reacting the following three components [1] to [3], [1] Diisocyanate compound [2] Dihydroxy organic compound [3] Hydroxy group-containing methacrylate or hydroxy group-containing acrylate (b) 0.01 to 10 parts by weight of organic peroxide, (c) Reaction of the following [1] and [2] A thermosetting resin composition containing 0.1 to 10 parts by weight of product [1] acrylic compound [2] diisocyanate compound. (2) (a) To 100 parts by weight of a radically polymerizable vinyl monomer solution containing 30% by weight or more of urethane methacrylate or urethane acrylate obtained by sequentially reacting the following three components [1] to [3], [1] Diisocyanate compound [2] Dihydroxy organic compound [3] Hydroxy group-containing methacrylate or hydroxy group-containing acrylate (b) 0.01 to 10 parts by weight of organic peroxide, (c) Reaction of the following [1] and [2] Product [1] Acrylic compound [2] Thermosetting resin composition prepared by adding 0.1 to 10 parts by weight of a diisocyanate compound and curing it in a mold at a temperature range of 30 to 200°C. A method for molding a resin composition.