WO2013035891A2

WO2013035891A2 - Radically polymerizable compound and radically curable composition

Info

Publication number: WO2013035891A2
Application number: PCT/JP2012/073554
Authority: WO
Inventors: Yasuyuki Oyama; Hirofumi Inoue
Original assignee: Showa Denko K.K.
Priority date: 2011-09-09
Filing date: 2012-09-07
Publication date: 2013-03-14
Also published as: TW201326231A; JP6039322B2; JP2013067792A; WO2013035891A3; WO2013035891A8

Abstract

The present invention provides a radically curable composition comprising a radically polymerizable compound (polyallyl ester compound) containing terminal groups represented by formulae (1) and (2) (in formula (1), X¹ represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group) and having a structure represented by formula (3) (in the formula, R¹ and R² independently represent an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X² represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group; and n and m represent an arbitrary positive integer); and having a number average molecular weight of 500 to 50,000. The cured product obtained by curing the radically curable composition of the present invention possesses flexibility and handleability while maintaining high transparency and heat resistance.

Description

DESCRIPTION

Radically Polymeri zable Compound and Radically Curable Composition

TECHNICAL FIELD

The present invention relates to a radically polymerizable compound and a radically curable

composition. Specifically, a radically polymerizable compound having an allyl ester structure and a carbonate structure within a molecule; a method for producing the same; a curable composition containing the radically polymerizable compound; and optical materials being excellent in transparency and heat resistance as well as having flexibility and handleability, which are obtained by curing the curable composition.

BACKGROUND ART

Conventionally, a cured product obtained by polymerizing and curing a polyallyl ester compound

containing multiple, allyl ester structures in a molecule is excellent in transparency and heat resistance, and has been used for optical materials, electronics, artificial marble, decorative laminates and an anti-cracking agent for unsaturated polyester resin. For example, EP 1331494 (Patent Document 1) discloses an optical lens using a polyaAlyl ester compound, U.S. Patent No. 7,989,563

(Patent Document 2) discloses a film using polyallyl ester compound and JP-A-2010-84008 (Patent Document 3) discloses a resin composition comprising a polyallyl ester compound as an essential ingredient and a semiconductor device using the same, respectively.

In order to respond to the demand for higher functionality, downsizing, thinner size and reduction in weight in electronics represented by mobile phones and thin-screen televisions, resin members have started to overtake glass members in optical materials used in the electronics .

Heat resistance and transparency near to those of glass, and the characteristics of being lighter in weight and more difficult to break compared to glass are required for resin used as a substitute for glass.

As resin used for the above purpose, polyethylene terephthalate , polycarbonate and the like are known. However, the grass transition temperature of the resin is about 70°C and 140°C, respectively, and it cannot be said that the heat resistance of the resin is

sufficient, which has limited their usefulness.

Although the cured product obtained by

polymerizing and curing a polyallyl ester compound has higher heat resistance and transparency compared to polyethylene terephthalate and polycarbonate, it cannot be said that the cured product has sufficient flexibility depending on the use, and there has been a strong demand for resin having moderate flexibility in addition to transparency and heat resistance.

As a method for improving the flexibility of a thermosetting resin, it has been attempted to incorporate a highly flexible structure represented by a polyether structure and the like into a molecular chain, to add core-shell rubber (e.g. JP-A-2011-5773 : Patent Document 4) and to incorporate a thermoplastic resin (e.g. JP-A- 2010-202862: Patent Document 5). However, decrease in light resistance and transparency, reduction in

handleability due to increase in viscosity, and the like have become a problem.

PRIOR ART DOCUMENTS

[Patent Documents]

[Patent Document 1] EP 1331494

[Patent Document 2] U.S. Patent No. 7,989,563

[Patent Document 3] JP-A-2010-84008

[Patent Document 4] JP-A-2011-57734

[Patent Document 5] JP-A-2010-202862

DISCLOSURE OF THE INVENTION

[Problems to be Solved by the Invention]

An objective of the present invention is to provide a resin composition which can attain flexibility while maintaining high transparency, heat resistance and handleability of the cured product obtained by curing a polyallyl ester compound.

[Means to Solve the Problem]

As a result of intensive study to solve the above problem, the present inventors have found that the flexibility of the cured product obtained by polymerizing a polyallyl ester compound and a polyallyl carbonate compound can be improved while maintaining the

transparency, heat resistance and handleability by copolymerizing the compounds with a radically polymerizable compound having a specific structure; and have accomplished the present invention.

That is, the present invention is shown in [1] to [14] below.

[1] A radically polymerizable compound containing terminal groups represented by formula (1)

(in the formula, X¹ represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group) and formula (2)

having a structure represented by formula

(in the formula, R¹ and R² independently represent an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X² represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group; and n and m represents an arbitrary positive integer) ; and having a number average molecular weight of 500 to 50,000.

[2] The radically polymeri zable compound as described in [1] above further having a structure

represented by formula (4)

(in the formula, R³ represents an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X³ represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group; and q represents an arbitrary positive integer) .

[3] The radically polymeri zable compound as described in [1] or [2] above, wherein X¹, X² and X³ independently represent a cycloalkylene group represented by any of formulae (5), (6) and (7).

(5) (6) (7)

[4] The radically polymeri zable compound as described in any of [1] to [3] above, wherein at least member of R¹, R² and R³ is an alkylene group having 1 to carbon atoms and having an alkyl branch.

[5] The radically polymeri zable compound as described in any of [1] to [4] above, wherein R¹ and R² are 1,6-hexylene group or 2 -methyl- 1 , 5-pentylene group.

[6] The radically polymerizable compound as.

described in any of [1] to [4] above, wherein R¹ and R² are nonylene group.

[7] The radically polymerizable compound as

described in [1] above represented by formula (8), wherein R¹ represents R⁴, R² represents R⁵, and X¹ and X² are 1,4- cyclohexylene group

(in the formula, R⁴ and R⁵ independently represent -(CH₂)₆- or - (CH₂) ₂CH (CH₃) (CH₂)₂-, and n and m represent an arbitrary positive integer) .

[8] A radically curable composition comprising a radically polymerizable compound containing terminal groups represented by formula (1)

and having a structure represented by formula (3)

(in the formula, R¹ and R² independently represent an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X² represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group; and n and m represent an arbitrary positive integer) ; and having a number average molecular weight of 500 to 50,000; a radically polymeri zable compound having allyloxycarbonyl group

(CH₂=CH-CH₂-0-CO-) or allyloxycarbonyloxy group (CH₂=CH- CH₂-0-C0-0-) at its terminal; and a radical polymerization initiator.

[9] The radically curable composition as described in [8] above, wherein a radically polymeri zable compound having allyloxycarbonyl group at its terminal is a

condensate of dicarboxylic acid diallyl ester and/or dicarboxylic acid diallyl ester and polyalcohol.

[10] A method for producing the radically

polymeri zable compound described in any one of [1] to [6] above by subjecting a compound represented by formula (10)

(in the formula, X⁴ represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group) and polycarbonate diol to transesterification in the presence of a catalyst.

[11] The method for producing a radically

polymerizable compound as described in [10] above, wherein the catalyst is at least one member selected from the group consisting of tetraisopropoxy titanium, tetrabutoxy titanium, dibutyltin oxide, dioctyltin oxide, hafnium acetylacetonate and zirconium acetylacetonate .

[12] The method for producing a radically

polymerizable compound as described. in [10] or [11] above, wherein the reaction is performed at a temperature lower than 180°C.

[13] An optical material obtained by curing the radically curable composition described in [8] above.

[14] An optical film, optical sheet, optical

waveguide, optical lens, optical encapsulant, optical adhesive or light guide plate using the optical material described in [13] above.

EFFECTS OF THE INVENTION

Use of the radically polymerizable compound of the present invention enables provision of a curable composition which can attain flexibility and handleability while maintaining high transparency and heat resistance of the cured product obtained by curing a polyallyl ester compound which has been conventionally known as being excellent in heat resistance and transparency. BRIEF DESCRIPTION OF DRAWINGS

[Fig. 1] ¹H-NMR spectrum of radically polymerizable compound A prepared in Example 1

[Fig. 2] ¹³C-NMR spectrum of radically polymerizable compound A prepared in Example 1

[Fig. 3] IR spectrum of radically polymerizable compound

A prepared in Example 1

[Fig. 4] i-H-NMR spectrum of radically polymerizable compound B prepared in Example 2

[Fig. 5] ¹³C-NMR spectrum of radically polymerizable compound B prepared in Example 2

[Fig. 6] IR spectrum of radically polymerizable compound

B prepared in Example 2

[Fig. 7] i-H-NMR spectrum of radically polymerizable compound C prepared in Example 3

[Fig. 8] ¹³C-NMR spectrum of radically polymerizable compound C prepared in Example 3

[Fig. 9] IR spectrum of radically polymerizable compound

C prepared in Example 3

[Fig. 10] ¹H-NMR spectrum of radically polymerizable compound D prepared in Example 4

[Fig. 11] ¹³C-NMR spectrum of radically polymerizable compound D prepared in Example 4

[Fig. 12] IR spectrum of radically polymerizable compound D prepared in Example 4

EMBODIMENT FOR CARRYING OUT THE INVENTION

Hereinafter, the embodiment of the present invention is described.

Radically polymerizable compound: The radically polymerizable compound used the present invention is a compound having a terminal group represented by formula (1) and formula (2)

(in the formula, X¹ represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group) and a structure represented by formula (3)

(in the formula, R¹ and R² independently represent an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X² represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group; and n and m represent an arbitrary positive integer) ; and having a number average molecular weight of 500 to 50,000.

Also, the radically polymerizable compound of the present invention may further have a structure represented by formula (4)

(in the formula, R³ represents an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X³ represents a cycloal kylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a

substituent group; and q represents an arbitrary positive integer) .

The number average molecular weight of the radically polymeri zable compound of the present invention is 500 to 50,000, preferably 1,000 to 10,000 and more preferably 1,500 to 5,000. The number average molecular weight is a value in terms of polystyrene measured by gel permeation chromatography (GPC) . When the number average molecular weight is less than 500, it may reduce the effect of imparting flexibility. When the number average molecular weight exceeds 50,000, it increases the

viscosity of the radically polymeri zable compound and decreases handleability . Also, it reduces the

compatibility with a polyallyl ester compound, which may raise the possibility of haze of the cured product.

In formula (3), n and m are an arbitrary positive interger. The molecular weight of the radically polymerizable compound of the present invention has a distribution wherein the number average molecular weight becomes 500 to 50,000. The n and m values indicate such a number of repeating units as to make the number average molecular weight fall within the above-mentioned range. Accordingly, the n and m values cannot be defined unambiguously, but n is 1 to 1500, preferably 1 to 1,000 and more preferably 1 to 500. Similarly, m is 1 to 1,700, preferably 1 to 330 and more preferably 1 to 180.

In formula (4), q is an arbitrary positive integer. For the same reason as in the case of n and m, the q value cannot be unambiguously defined but is 1 to 1,500, preferably 1 to 1,000 and more preferably 1 to 500.

In formulae (1), (2) and (3), X¹, X² and X³ represent a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a

substituent group. Although it is preferable that X¹, X² and X³ are the same but they may be different from each other.

The method for producing the radically polymerizable compound of the present invention is to be described later, and dicarboxylic acid diallyl ester containing a structure of X¹, X² and X³ is used as a part of the raw materials. When one kind of dicarboxylic acid diallyl ester is used as a raw material, X¹, X² and X³ will be the same and when different kinds of dicarboxylic acid diallyl esters are used, X¹, X² and X³ may be different from each other in some cases. X² may be different

depending on each of the unit structures in formula (3) which are contained in the radically polymerizable

compound as many as number "m" .

As the cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group

represented by X¹, X² and X³, a cycloalkylene group having 6 to 8 carbon atoms is preferable from the viewpoint of the balance between heat resistance, transparency and handleability . The cycloalkylene group having 5 to 10 carbon atoms may be monocyclic or may have more than one cyclic structure as in bicycloalkylene group. As a cycloalkylene group having 5 to 10 carbon atoms, preferred are cyclohexylene group, norbornylene group and

bicyclodecylene group from the viewpoint of heat

resistance.

Examples of a substituent group of

cycloalkylene group having 5 to 10 carbon atoms include alkyl group such as methyl group and ethyl group.

Specific examples of cycloalkylene group having 5 to 10 carbon atoms which may contain a substituent group include 1 , 2-cyclopentylene group, 1 , 3 -cyclopentylene group, 1 , 2-cyclohexylene group, 1 , 3-cyclohexylene group, 1 , 4-cyclohexylene group, methylcyclohexylene group, dimethylcyclohexylene group, cycloheptylene group, 1- ethylcyclopentylene group, cyclooctylene group,

cyclononylene group, cyclodecylene group, bicyclodecylene group, norbornylene group and cyclohexanedimethylene group. Among these, 1 , 2-cyclohexylene group, 1,3- cyclohexylene group, 1 , 4-cyclohexylene group, norbornylene group and bicyclodecylene group are preferable because a cured product being excellent in heat resistance can be obtained. 1 , 2-cyclohexylene group, 1 , 3-cyclohexylene group, 1 , 4-cyclohexylene group and norbornylene group are still more preferable because the radically polymeri zable compound produced thereof has a relatively low viscosity and high handleability. 1 , 2 -cyclohexylene group, 1 , 3-cyclohexylene group and 1 , 4 -cyclohexylene group are represented by the following formulae (5), (6) and (7), respectively.

(5) (6) (7)

As alkylene group having 2 to 10 carbon atoms which may have a substituent and is represented by X¹, X² and X³, alkylene group having 2 to 8 carbon atoms is preferable from the viewpoint of versatility.

Examples of the substituent of alkylene group having 2 to 10 carbon atoms include alkyl group such as methyl group and ethyl group.

Specific examples of alkylene group having 2 to 10 carbon atoms which may have a substituent include ethylene group, propylene group, butylene group, pentylene group, hexylene group, heptylene group, octylene group, nonylene group and decylene group. Among these, ethylene group, propylene group, butylene group and octylene group are preferable from the viewpoint of versatility.

R¹ and R² in formula (3) independently represent alkylene group having 2 to 20 carbon atoms which may have an alkyl branch.

The alkylene structure of R¹ and R² is derived from carbonate diol, which is one of the materials of the radically polymeri zable compound of the present invention.

R^xs which are contained in formula (3) as many as n may be the same with or different from each other. If there are several kinds of alkylene groups corresponding to R¹ and R² in carbonate diol ( copolymerization type) as a raw

material, it results in the presence of several kinds of R^ls .

The alkylene group having 2 to 20 carbon atoms which may have an alkyl branch is preferably alkylene group having 2 to 10 carbon atoms from the viewpoint of the balance between the flexibility and handleability of the cured product thereof, and alkylene group having 4 to 9 carbon atoms is more preferable. As an alkyl branch, alkyl group having 1 to 3 carbon atoms is preferable.

There may be two or more of alkyl branches.

Examples of alkylene group represented by R¹ and R2 include those having a linear structure and a branched structure.

Specific examples of linear alkylene group include ethylene group, propylene group, butylene group, pentylene group, hexylene group, heptylene group, octylene group, nonylene group and decylene group. Among these, butylene group, hexylene group and nonylene group are preferable .

Specific examples of alkylene group having a branched structure, i.e. alkylene group having 2 to 20 cabon atoms which has an alkyl branch, include methyl ethylene group, 1-methyl-propylene group, 2-methyl- propylene group, 2-ethyl-3-propylpropylene group, 2-ethyl- 2 -butylpropylene group, 1-methylpentylene group, 2- methylpentylene group, 3-methylpentylene group, 2,4- dimethylpentylene group and 1-methyloctylene group.

The structure of R³ in formula (4) representing alkylene group having 2 to 20 carbon atoms which may have an alkyl branch is derived from alkylene diol as an

optional raw material of the radically polymerizable compound of the present invention. Specific examples of R³ include the same those in the case of as the alkylene group having 2 to 20 carbon atoms which may have an alkyl branch represented by R¹ and R² as mentioned above.

Furthermore, it is preferable that at least one of R¹, R² and R³ is alkylene group having a branched

structure. By making R¹, R² or R³ have a branched

structure, it becomes possible to suppress the

crystallinity of the radically polymerizable compound to thereby lower the viscosity and melting point, which enables improvement of the handleability of the radically polymerizable compound. Among the alkylene groups having a branched structure, 2-methyl-propylene group, 2-ethyl-2- butylpropylene group, 2-methylpentylene group, 3- methylpentylene group, 2 , 4-dimethylpentylene group and 2- methyloctylene group are particularly preferable.

The ratio of the alkylene groups having a branched structure to the total amount of alkylene groups represented by R¹, R² and R³ in the radically polymerizable compound of the present invention is preferably 10 mol% or more, and more preferably 30 mol% or more.

When X¹ and X² are 1 , 4 -cyclohexylene group and

R¹, R² or R³ are hexylene group or 2-methylpentylene group, the radically polymerizable compound of the present .

invention is represented by formula (8)

When X¹ and X² are 1 , -cyclohexylene group and R¹, R² or R³ are nonylene group which may have an alkyl branch, the radically polymerizable compound of the

present invention is represented by formula (9)

(in the formula, R⁶ and R⁷ independently represent -(CH₂)₉- or - (CH) ₂CH (CH₃) (CH₂)₆-, and n and m represent an arbitrary positive integer) .

Production method of a radically polymerizable compound:

The radically polymerizable compound of the present invention can be produced by subjecting the

compound represented by formula (10)

(in the formula, X⁴ represents cycloal kylene group having 5 to 10 carbon atoms which may have a substituent or alkylene group having 2 to 10 carbon atoms which may have a substituent) and polycarbonate diol to

transesterification in the presence of a catalyst while distilling away allyl alcohol generated as a by-product.

Examples of cycloalkylene group having 5 to 10 carbon atoms which may have a substituent or alkylene group having 2 to 10 carbon atoms which may have a

substituent represented by X⁴ include the same group as the examples of the cycloalkylene group having 5 to 10 carbon atoms which may have a substituent or alkylene group having 2 to 10 carbon atoms which may have a

substituent represented by X¹, X² and X³. X⁴ can be

appropriately selected depending on the structures

represented by formulae (1), (3) and (4) as the target substance. X⁴ is not limited to one kind and several kinds of compounds represented by formula (10) can be used.

Specific examples of the compound represented by formula (10) include diallyl 1,2- cyclohexanediacrboxylate , diallyl 1,3- cyclohexanedicarboxylate , diallyl 1,4- cyclohexanedicarboxyate , diallyl

endomethylenetetrahydrophthalate , diallyl

methyltetrahydrophthalate , diallyl decahydronaphthalate , diallyl 5-norbornene-2 , 3-dicarboxylate, diallyl adipate, diallyl succinate and diallyl maleate. Two or more of these compounds can be used in combination as needed. The compound is not limited to the above mentioned specific examples.

Polycarbonate diol used for producing the radically polymeri zable compound is represented by formula (11) .

In the formula, R¹ and R² independently

represent alkylene group having 2 to 20 carbon atoms as mentioned above (as in the case of formula (3) ) .

As described above, it is more preferable that at least one of R¹ and R² is alkylene group having a branch in the radically polymerizable compound of the present invention. Among the alkylene group having a branch, the one not having a branch at the terminal carbon is

particularly preferable. In polycarbonate diol derived from alkylene group not having a branch at the terminal, all the hydroxyl groups in a molecule become a primary hydroxyl group, which can increase the reaction rate of transesterification and is preferable from the viewpoint of productivity. When the alkylene group has a

substituent at the terminal, it decreases the reaction rate and therefore reduces the productivity. Specific examples of alkylene group having a branch and not having a branch at the terminal carbon include 2-methyl-propylene group, 2-ethyl-2-butylpropylene group, 2-methylpentylene group, 3-methylpentylene group, 2 , -dimethylpentylene group and 2 -methyloctylene group.

Two or more kinds of polycarbonate diol may be used in combination as needed. Polycarbonate diol is not limited to the above-mentioned specific examples.

Polycarbonate diol used for the reaction is generally a condensate produced by transesterification of a carbonate compound such as dimethyl carbonate, diphenyl carbonate and ethylene carbonate with diol, which is an aggregate of oligomers having different molecular weight, and has a molecular weight dist ibution.

The number average molecular weight of

polycarbonate diol used for the radically polymerizable compound of the present invention is preferably 300 to 10,000, and more preferably 500 to 3,000. When the average molecular weight is low, it makes it difficult to exhibit various properties derived from the polycarbonate structure such as heat resistance and ductility. When the average molecular weight is high, polycarbonate diol becomes solid and needs heating when used, which decreases workability. Also, it may lead to a problem such as haze of the cured product when a radically polymerizable compound which is synthesized using the polycarbonate diol is mixed with a polyallyl ester compound and cured.

When the radically polymerizable compound of the present invention has a structure represented by formula (4), alkylene diol as well as polycarbonate diol may be used as diol. Specific examples of alkylene diol include ethylene glycol, propylene glycol, 1,3-propane diol, 2-methyl-l, 3-propane diol, 2-ethyl-2-butyl-l , 3- propane diol, 1,3-butane diol, 1,4-butane diol, neopentyl glycol, 1,5-pentane diol, 2 , 4-dimethyl-l , 5-pentane diol, 3-methyl-l , 5-pentane diol, 1,6-hexane diol, 1,8-octane diol, 2-methyl-l, 8-octane diol and 1,9-nonane diol.

The molar ratio in feed between the compound represented by formula (10) and polylcarbonate diol is preferably 1.1:1 to 6:1 and more preferably 1.5:1 to 3:1.

When alkylene diol is used in combination, the molar ratio in feed between the compound represented by formula (10) and alkylene diol is preferably 1.1:1 to 6:1 and more preferably 1.5:1 to 3:1.

As a catalyst for transesterification, a conventionally-known transesterificatxon catalyst can be used. Specific examples thereof include alkali metal;

alkaline earth metal, and oxide and salt of weak acid thereof; Mn, U, Zn, Cd, Zr, Pb, Ti, Co, Sn and oxide, hydroxide, inorganic acid salt, alcoholate and organic acid salt thereof; and organic tin compounds such as dibutyl tin oxide, dioctyl tin oxide, dibutyl tin

dichloride. Among these, tetraiosopropoxy titanium, tetrabutoxy titanium, dibutyl tin oxide, dioctyl tin oxide, hafnium acetylacetonate and zirconium

acetylacetonate are preferable. Dibutyl tin oxide and dioctyl tin oxide are still more preferable.

The amount of catalyst used varies depending on the activity of the catalyst, and a catalyst is used in such an amount that can distil away allyl alcohol at an appropriate rate. Generally, a catalyst is used in an amount of 0.0001 to 1 mass%, and preferably about 0.001 to 0.5 mass% to diallyl ester compound represented by formula (10) .

The reaction temperature during the production process of the radically polymerizable compound of the present invention is preferably 180°C or less and more preferably 170°C or less, and still more preferably 160°C or less. The higher reaction temperature can reduce the reaction time but may lead to problems such as coloring and increase of the by-product amount. As an embodiment of the reaction, it is preferable to carry out the reaction while removing the allyl alcohol generated as a by-product out of the

reaction system by conducting the reaction under reduced pressure, with use of an appropriate solvent, etc. in order to accelerate the progress of the reaction.

Radically curable composition:

The radically curable composition of the

present invention (to be abbreviated as "composition of the present invention") is a composition containing the above-mentioned radically polymerizable compound of the present invention, a radically polymerizable compound having allyloxycarbonyl group (CH₂=CH-CH₂-0-CO-, which may be referred to as "allyl ester group") or

allyloxycarbonyloxy group ( CH₂=CH-CH₂-0-CO-0- , which may be referred to as "allyl carbonate group") at its terminal, and a radical polymerization initiator as essential ingredients. The composition of the present invention may contain other radically polymerizable compounds, a

reactive diluent (low-molecular weight monomer), a solvent and various additives (to be described later) other than the essential ingredients. The composition of the present invention can be prepared by mixing each of the above- mentioned components.

Specific examples of the radically

polymerizable compound having allyloxycarbonyl group at its terminal include diallyl ester compounds such as diallyl phthalate, diallyl terephthalate , diallyl

isophthalate , diallyl 1, 2-cyclohexanedicarboxylate, diallyl 1 , 3-cyclohexanedicarboxylate and diallyl 1,4- cyclohexanedicarboxylate ; and allyl ester oligomers obtained by transesterification of the above diallyl ester compounds and polyalcohol.

Specific examples of the radically

polymerizable compound having allyloxycarbonyloxy group at its terminal include allyl carbonate compounds represented by diethylene glycol bisallyl carbonate.

As a radically polymerizable compound having allyloxycarbonyl group or allyloxycarbonyloxy group at its terminal, preferred is a compound having an aliphatic structure or an alicyclic structure, and specific examples thereof include diallyl 1 , 2 -cyclohexanedicarboxylate diallyl 1 , 3-cyclohexanedicarboxylate, diallyl 1,4- cyclohexanedicarboxylate ; allyl ester oligomers obtained by transesterification of the above alicyclic diallyl ester compounds and polyalcohol; and diethylene glycol bisallyl carbonate.

Preferred polyalcohol used as a raw material of the above-mentioned allyl ester oligomer is polyalcohol having 2 to 20 carbon atoms. Examples of the bivalent alcohol include ethylene glycol, propylene glycol, 1,3- propane diol, 1,3-butane diol, 1,4-butane diol, neopenthyl glycol, hexamethylene glycol, 1 , 4 -cyclohexane dimethanol, 2-methyl-l , 3-propane diol and 3-methyl-l , 5-pentane diol. Specific examples of trivalent or higher polyalcohol include glycerin, trimethylolpropane , trimethylolethane , ditrimethylolpropane , pentaerythritol , dipentaerythritol and D-sorbitol. A mixture of two or more of the

polyalcohol can also be used. The polyalcohol is not limited to the above-mentioned specific examples.

The ratio by mass between the radically

polymerizable compound of the present invention and a radically polymerizable compound having allyloxycarbonyl group (or allyloxycarbonyloxy group) at its terminal is preferably 0.1-50:99.9-50, more preferably 0.5-30:99.5-70 and still more preferably 1-20:99-80. When the ratio by mass of the radically polymerizable compound of the present invention is too low, it cannot provide enough improvement in flexibility, while when the ratio by mass of the radically polymerizable compound of the present invention is too high, there is possibility of lowering the transparency and heat resistance inherent to the cured product obtained by polymerization of a radically

polymerizable compound having allyloxycarbonyl group (or allyloxycarbonyloxy group) .

Examples of the radical polymerization

initiator include organic peroxide, photopolymeri zat ion initiators and azo compounds.

Examples of organic peroxide include ketone peroxides such as methylethyl ketone peroxide,

methylisobutylketone peroxide and cyclohexanone peroxide; diacyl peroxides such as dibenzoyl peroxide, didecanoyl peroxide and dilauroyl peroxide;

dialkyl peroxides such as dicumyl peroxide, t-butylcumyl peroxide and di-t-butyl peroxide;

peroxyketals such as 1 , 1-di ( t-hexylperoxy) -3 , 3 , 5- trimethylcyclohexane , 1, 1-bis (t-hexylperoxy) cyclohexane, 1 , 1-di-t-butylperoxycyclohexane and 2,2-di(t- butylperoxy) butane ; alkylperoxy esters such as t-butylperoxypivalate , t- butylperoxy-2-ethylhexanoate , t-butylperoxyisobutyrate , di-t-butyIperoxyhexahydroterephthalate , di-t- butylperoxyazelate , t-butylperoxy-3 , 5, 5- trimethylhexanoate , t-hexylperoxy-2-ethylhexanoate ,

1,1,3, 3-tetramethylbutylperoxy-2-ethylhexanoate, t- butylperoxyacetate , t-butylperoxybenzoate , di-t- butylperoxytrimethyladipate , t- hexylperoxyisopropylmonocarbonate , t-butylperoxylaurate , and t-hexylperoxybenzoate ;

peroxycarbonates such as diisopropylperoxydicarbonate , di- sec-butylperoxydicarbonate, and t-butylperoxyisopropyl carbonate .

Examples of a photopolymeri zat ion initiator include acetophenone derivatives such as acetophenone , 2, 2-dimethoxy-2-phenylacetophenone, diethoxyacetophenone , 1-hydroxy-cyclohexylphenylketone, 2-methyl-l- [4- (methylthio) phenyl] -2-morpholinopropanone-l , 2-benzyl-2- dimethylamino-1- (4-morpholinophenyl) -butanone-1, and 2- hydroxy-2 -methyl-l-phenylpropane-1-one ;

benzophenone derivatives such as benzophenone , 4,4'- bis (dimethylamino) benzophenone, 4- trimethylsilylbenzophenone and 4-benzoyl- ' - methyldiphenyl sulfide;

benzoin derivatives such as benzoin, benzoinethylether , benzoinpropylether , benzoini sobutylether and

benzoinisopropylether;

methylphenylglyoxylate , benzoindimethylketal , and 2,4,6- trimethylbenzoyldiphenylphosphineoxide .

Examples of azo compounds include azo compounds such as 2 , 2 ' -azobisisobutyronitrile , 2,2'- azobisisovaleronitrile and dimethyl 2,2'- azobisisobutyrate .

Two or more of these radical polymerization initiators may be used may be used in combination.

The addition quantity of the polymerization initiator varies depending on the curing temperature, composition ratio of the radically curable composition, and type and amount of the additives and cannot be flatly defined. Generally, it is preferred that the amount be

0.01 to 10 parts by mass based on 100 parts by mass of the total amount of radically polymerizable components in the radically curable composition of the present invention, particularly preferably 0.1 to 5 parts by mass. If the addition quantity of the radical polymerization initiator is less than 0.01 parts by mass, it may lead to insufficient polymerization and curing. Adding the radical polymerization initiator in an amount exceeding 10 parts by mass is

undesirable in consideration for the cost.

The polymerization temperature (curing

temperature) may be appropriately determined according to the type of the radical polymerization initiator. In case of UV polymerization, room temperature may be employed. In case of heat polymerization, it is preferable that the polymerization (curing) temperature be determined

appropriately according to the decomposition temperature of the radical polymerization initiator and generally, the temperature is selected within the range of from 30 to 180 °C. The temperature may be gradually changed in

conducting polymerization (curing). The radically curable composition of the present invention may use various known additives such as ultraviolet absorbing agents, antioxidants, releasing agents, colorants, flow modifiers, leveling agents and inorganic filers.

Specific examples of ultraviolet absorbing agents include triazoles such as 2- ( 2 ' -hydroxy-tert- butylphenyl ) benzotria zole , benzophenones such as

2 , 4 -dihydroxybenzophenone , and salicylates such as 4-tert- butylphenyl salicylate.

The blending ratio of the ultraviolet absorbing agent varies depending on the kinds and amounts of the other ingredients, and generally it is preferred that the amount be 0.01 to 2 parts by mass based on 100 parts by mass of the total amount of radically polymerizable

components in the radically curable composition of the present invention, more preferably 0.03 to 1.7 parts by mass and most preferably 0.05 to 1.4 parts by mass. When the amount of the ultraviolet absorbing agent is less than 0.01 parts by mass, a desired effect cannot be achieved, while the amount exceeding 2 parts by mass is undesirable in consideration for the cost.

Examples of the antioxidants include phenol antioxidants such as 2 , 6-di-tert-butyl-4 -methylphenol , tetrakis- [methylene-3- ( 3 ' , 5 ' -di-tert-buty1 - 4 -hydroxyphenyl ) propionate ] methane , sulfur antioxidants such as dilauryl-3 , 3 ' -thiodipropionate , phosphorous antioxidants such as tris nonylphenyl phosphite, and hindered amines such as bis - ( 2 , 2 , 6 , 6-tetramethyl-4 - piperidinyl) sebacate.

The blending ratio of the antioxidant varies depending on the kinds and amounts of the other

ingredients, and generally it is preferred that the amount be 0.01 to 5 parts by mass based on 100 parts by mass of the total amount of radically polymerizable components in the radically curable composition of the present invention, more preferably 0.05 to 4 parts by mass and most preferably 1 to 3 parts by mass. When the amount of the antioxidant is less than 0.01 parts by mass, a desired effect cannot be achieved, while the amount exceeding 5 parts by mass is undesirable in consideration for the cost.

Examples of the releasing agent include stearic acid, butyl stearate, zinc stearate, amide stearate, fluorine compounds and silicone compounds.

The blending ratio of the releasing agent varies depending on the kinds and amounts of the other ingredients, and generally it is preferred that the amount be 0.01 to 2 parts by mass based on 100 parts by mass of the total amount of radically polymerizable components in the radically curable composition of the present invention, more preferably 0.03 to 1.7 parts by mass and most preferably 0.05 to 1.4 parts by mass. When the amount of the releasing agent is less than 0.01 parts by mass, a desired effect cannot be achieved, while the amount exceeding 2 parts by mass is undesirable in consideration for the cost.

Examples of the colorants include organic pigments such as anthraquinone pigment, azo bigment, carbonium pigment, quinoline pigment, quinoneimine

pigment, indigoid pigment and phthalocyanine pigment; and organic dyes such as azoic dye and sulfide dye; and

inorganic pigments such as titanium yellow, iron oxide yellow, zinc yellow, chromium orange, molybdenum red, cobalt purple, cobalt blue, cobalt green, chromium oxide, titanium oxide, zinc sulfide and carbon black. The blending ratio of the colorant is not particularly

limited .

The radically curable composition of the present invention can be molded by being mixed with inorganic filler and inorganic fiber as needed. Specific examples of the inorganic filler include calcium

carbonate, clay, aluminum hydroxide, talc, mica, silica and glass beads, and the inorganic filler is not limited to the examples. Specific examples of inorganic fiber include glass fiber and carbon fiber, and the inorganic fiber is not limited to the examples.

The radically curable composition of the present composition can be molded by cast molding,

compression molding, transfer molding, injection molding and protrusion molding.

In the case of cast molding, a method of adding a radical polymerization initiator to the composition, injecting the resulting composition into a mold fixed by elastomeric gasket and a spacer through the use of a production line, and curing the composition by heat in an oven can be employed. The mold to be used is preferably made of glass or metal.

EXAMPLES

The present invention is to be described in more details referring to Examples and Comparative

Examples, but the present invention will not be limited thereto.

Various properties of the radically polymerizable compounds prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were measured as described below.

[Hazen units]

The Hazen units of the radically polymerizable compound were measured according to JIS K0071 by

comparison with the standard solution using a colorimetric tube.

[Number average molecular weight]

Apparatus used: Gel permeation chromatography (GPC) system SIC-480II manufactured by SHOWA DENKO K.K.

Column: Columns for gel permeation chromatography

(GPC): K-801, K-802 and K-802.5 manufactured by SHOWA DENKO K.K.

Detector: RI-201H manufactured by SHOWA DENKO K.K.

Eluant : chloroform

Measurement method: 100 μΐ of the sample dissolved in chloroform was introduced to the column in which the temperature is adjusted to 40°C, to thereby measure the number average molecular weight in terms of polystyrene. [ ¹ H-NMR, ¹³C-NMR]

Apparatus used: JEOL EX-400 (400 MHz), manufactured by JEOL, LTD.

Measurement method: measured by dissolving samples in deuterated chloroform and using tetramethylsilane as internal standard. [FT-IR]

Apparatus used: Spectrum GX, manufactured by PerkinElmer, Inc .

Measurement method: measured by liquid membrane technique using a KBr plate

[Handleability] : The sample which was liquid and flowable at 25°C was graded o, while the sample which was not flowable was graded x.

[Viscosity]

Apparatus used: TVE-20H, manufactured by Toki Sangyo Co., Ltd.

Measurement method: measured at a liquid temperature of 25°C using a cone-plate viscometer and a rotor No. 1°34' x R24.

Various properties of the cured products prepared in Examples 5 to 8 and Comparative Examples 5 to 9 were measured as described below.

[Degree of yellowness of the cured product]

Apparatus used: Color meter ZE6000 manufactured by Nippon Denshoku Industries Co., Ltd.

Measurement method: The yellow index (YI) of the cured plate 50 millimeters long, 50 millimeters wide and 3 millimeters thick was measured according to ASTM E313 (C light source/2" field of vision).

[Haze of the cured product]

Apparatus used: Turbidity meter NDH2000 manufactured by Nihon Denshoku Industries Co., Ltd.

Measurement method: measured according to JIS K7136, using the sample plate 50 millimeters long, 50 millimeters wide and 3 millimeters thick of the cured product

[Total light transmittance ]

Measurement method: measured according to JIS K7361-1, using the sample plate 50 millimeters long, 50 millimeters wide and 3 millimeters thick of the cured product

[Coefficient of linear thermal expansion]

Apparatus used: Thermo mechanical analyzer TMA/SS7100, manufactured by SII Nanotechnology Inc.

Measurement method: Applying pressure of 4.0 kPa to the sample plate 8 millimeters long, 8 millimeters wide and 3 millimeters thick of the cured product, the plate was heated from 30°C to 260°C at a heating rate of 5°C/min., cooled to 30°C, and heated again from 30°C to 260°C at a heating rate of 5°C/min. The coefficient of linear

thermal expansion was determined from the amount of thickness change of the sample plate.

[Pencil hardness]

The pencil hardness of the sample plate 50 millimeters long, 50 millimeters wide and 3 millimeters thick of the cured product was measured according to JIS- K6894. [Bending test (flexural strength, elastic modulus, fracture strain) ]

Apparatus used: Universal tester AG-1 manufactured by Shimadzu Corporation

Measurement method: Three point bending test was

conducted according to JIS K7171 using a sample plate (60 mm x 25 mm x 3 mm) with a distance of 48 mm provided between the fulcrums at a test rate of 1 mm/min. Example 1: Radically polymerizable compound (A)

400 g of diallyl 1 , -cyclohexanedicarboxylate , 800 g of polycarbonate diol (UH-100 manufactured by Asahi Kasei Corp., number average molecular weight: 1000, alkylene group: 1,6-hexylene group, positive integer n in formula (11) is 1 to 153) and 1.0 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 160°C to carry out the reaction. Allyl alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa, and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was about six hours. After cooling, the reaction liquid was taken out to obtain 1052 g of radically polymerizable compound (A) .

The obtained radically polymerizable compound was liquid at room temperature, wherein Hazen units was 10, viscosity at 25°C was 15000 mPa-s and number average molecular weight in terms of polystyrene was 3407. As a result of ¹³C-NMR measurement of radically polymerizable compound (A) , a peak derived from -OCOO- group was confirmed at 5=155.5 ppm. From the measurement result of gel permeation chromatography (GPC) , positive integer m in formula (3) was within the range from about 1 to 64.

1H-N R spectrum, ¹³C-NMR and IR spectrum of radically polymerizable compound (A) are respectively shown in Figures 1, 2 and 3.

Example 2: Radically polymerizable compound (B)

400 g of diallyl 1 , 4 -cyclohexanedicarboxylate ,

800 g of polycarbonate diol (C1015N manufactured by

Kuraray Co., Ltd., number average molecular weight: 1000, alkylene group: 1,9-nonylene group, 2 -methyl-1 , 8 -octylene group, linear/branched=15/85 (mol/mol), positive integer n in formula (11) is 1 to 116) and 0.4 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 160°C to carry out the reaction. Allyl

alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa, and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was about eight hours. After cooling, the reaction liquid was taken out to obtain 1067 g of radically polymerizable compound (B) .

The obtained radically polymerizable compound was liquid at room temperature, wherein Hazen units was 30, viscosity at 25°C was 10000 mPa · s and number average molecular weight in terms of polystyrene was 4197. As a result of ¹³C-NMR measurement of radically polymerizable compound (B) , a peak derived from -OCOO- group was confirmed at 5=155.3 ppm. From the measurement result of gel permeation chromatography (GPC) , positive integer m in formula (3) was within the range from about 1 to 79.

!H-NMR spectrum, ¹³C-NMR spectrum and IR

spectrum of radically polymerizable compound (B) are respectively shown in Figures 4, 5 and 6.

Example 3: Radically polymerizable compound (C)

400 g of diallyl 1 , -cyclohexanedicarboxylate ,

400 g of polycarbonate diol (C590 manufactured by Kuraray Co., Ltd., number average molecular weight: 500, alkylene group: 1,6-hexylene group, 2-methyl-l , 5-pentylene group, linear/branched=l 0 / 90 (mol/mol), positive integer n in formula (11) is 1 to 76) and 0.4 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 160°C to carry out the reaction. Allyl alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa, and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was about seven hours. After cooling, the reaction liquid was taken out to obtain 751 g of radically polymerizable compound (C) .

The obtained radically polymerizable compound was liquid at room temperature, wherein Hazen units was 15, viscosity at 25°C was 3300 mPa · s and number average molecular weight in terms of polystyrene was 2067. As a result of ¹³C-NMR measurement of radically polymerizable compound (C) , a peak derived from -OCOO- group was confirmed at 6=155.2 ppm. From the measurement result of gel permeation chromatography (GPC) , positive integer m in formula (3) was within the range from about 1 to 68.

!H- MR spectrum, ¹³C-NMR spectrum and IR

spectrum of radically polymeri zable compound (C) are respectively shown in Figures 7, 8 and 9.

Example 4: Radically polymeri zable compound (D)

400 g of diallyl 1, 4-cyclohexanedicarboxylate,

400 g of polycarbonate diol (UH-100 manufactured by Asahi Kasei Corp., number average molecular weight: 1000, alkylene group: 1,6-hexylene group, positive irfteger n in formula (10) is 1 to 153), 46 g of 3-methyl-l , 5- pentanediol (manufactured by Wako Pure Chemical

Industries, Ltd.) and 1.0 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 160°C to carry out the reaction. Allyl

alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa, and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was about six hours. After cooling, the reaction liquid was taken out to obtain 751 g of radically polymeri zable compound ( D) .

The obtained radically polymeri zable compound was liquid at room temperature, wherein Hazen units was 25, viscosity at 25°C was 5200 mPa · s and number average molecular weight in terms of polystyrene was 2302. As a result of ¹³C-NMR measurement of radically polymerizable compound (D), a peak derived from -0C00- group was

confirmed at 5=155.3 ppm.

¹H-NMR spectrum, ¹³C-NMR spectrum and IR

spectrum of radically polymerizable compound (D) are respectively shown in Figures 10, 11 and 12.

Comparative Example 1: Radically polymerizable compound (E)

300 g of diallyl 1 , 4-cyclohexanedicarboxylate ,

75 g of 1 , 2-propylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.75 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 180°C to carry out the reaction. Allyl alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was about 20 hours. After cooling, the reaction liquid was taken out to obtain 291 g of radically polymerizable compound (E) .

The obtained radically polymerizable compound was semisolid at room temperature. The number average molecular weight in terms of polystyrene of the compound was 1805.

Comparative Example 2: Radically polymerizable compound (F)

300 g of diallyl 1, 4-cyclohexanedicarboxylate, 75 g of 3-methyl-l , 5-pentanediol (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.75 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 180°C to carry out the reaction. Allyl alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was about five hours. After cooling, the reaction liquid was taken out to obtain 241 g of radically polymerizable compound ( F) .

The obtained radically polymerizable compound was liquid at room temperature and had a viscosity of 19800 mPa · s at 25°C. The number average molecular weight in terms of polystyrene of the compound was 2606.

Comparative Example 3: Radically polymerizable compound (G)

144 g of diallyl 1 , 4 -cyclohexanedicarboxylate ,

277 g of polytetramethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.; average molecular weight: 1000) and 0.35 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 180°C to carry out the reaction. Allyl alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was about four hours. After cooling, the reaction liquid was taken out to obtain 371 g of radically polymerizable compound (G) .

The obtained radically polymerizable compound was liquid at room temperature and had Hazen units of 35, a viscosity of 3130 mPa-s at 25°C, and a number average molecular weight in terms of polystyrene of the compound of 3647.

Comparative Example 4: Radically polymerizable compound (H)

144 g of diallyl 1 , -cyclohexanedicarboxylate , 277 g of polypropylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.; average molecular weight: 1000, diol type) and 0.36 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to

180°C to carry out the reaction. Allyl alcohol generated as the reaction progresses was distilled away. The

reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa and was

terminated at the point when the theoretical amount of allyl alcohol was distilled away. The reaction time was 18 hours. After cooling, the reaction liquid was taken out to obtain 815 g of radically polymerizable compound (H) .

The obtained radically polymerizable compound was liquid at room temperature and had and had Hazen units of 35, a viscosity. of 4500 mPa · s at 25°C, and a number average molecular weight in terms of polystyrene of the compound of 3728. Synthesis Example 1: Polyallyl ester compound (a)

500 g of diallyl 1 , -cyclohexanedicarboxylate , 59 g of trimethylolpropane (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.5 g of dioctyltin oxide were charged in a three-neck flask and heated by oil bath adjusted to 180°C to carry out the reaction. Allyl alcohol generated as the reaction progresses was distilled away. The reaction was performed while the pressure was gradually reduced from ordinary pressure to 1.4 kPa and was terminated at the point when the theoretical amount of allyl alcohol was distilled away. After cooling, the reaction liquid was taken out to obtain 472 g of polyallyl ester compound (a) .

The results of Examples 1 to 4 and Comparative Examples 1 to 4 are shown in Table 1.

Table 1

Examples 5 to 8 and Comparative Examples 5 to 9:

Polyallyl ester compound (a), a radically polymerizable compound and a radical polymerization initiator (PERHEXYL I manufactured by NOF Corporation; t- hexylperoxyisopropyl monocarbonate) were charged in a 100 ml polyethylene container at the composition ratio (ratio by mass) shown in Table 2 and stirred with a glass rod to be uniformly mixed under room temperature to thereby prepare a radically curable composition. The radically curable composition was poured into a mold 15 centimeters wide, 20 centimeters high and 3 millimeters thick,

comprising two glass plates and spacers made of silicone rubber strands, placed in a circulating hot air oven and heated at 90°C for one hour. Subsequently, the

temperature was elevated to 130°C for two hours and the composition was heated at 130°C for one hour. After finishing the curing, the mold was removed and the

composition was subjected to curing at 160°C for one hour to obtain a plate-shaped cured product. The cured product was cut into a predetermined size using a diamond cutter and subjected to the above various measurements. The results are shown in Table 2.

Table 2

As shown in Table 2, use of the radically polymeri zable compound of the present invention made it possible to obtain a cured product having flexibility while maintaining various properties such as heat

resistance, transparency and light resistant inherent to a polyallyl ester compound.

When a compound having an ether strucure or an alkylene strucure generally used for the purpose of imparting flexibility was introduced in the composition, significant decrease in transparency and decrease in handleability of the cured product were observed.

Claims

1. A radically polymeri zable compound containing terminal groups represented by formula (1)

having a structure represented by formula

(in the formula, R¹ and R² independently represent an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X² represents a cycloalkylene group having 5 to 10 carbon atoms which may have a. substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group; and n and m

represents an arbitrary positive integer) ; and having a number average molecular weight of 500 to 50,000.

2. The radically polymeri zable compound as claimed in claim 1 further having a structure represented by formula (4)

3. The radically polymeri zable compound as claimed in claim 1 or 2, wherein X¹, X² and X³

independently represent a cycloalkylene group represented by any of formulae (5) , (6) and (7) .

(5) (6) (7)

4. The radically polymeri zable compound as claimed in claim 1 or 2, wherein at least one member of R¹, R² and R³ is an alkylene group having 1 to 4 carbon atoms and having an alkyl branch.

5. The radically polymeri zable compound as claimed in claim 1, wherein R¹ and R² are 1,6-hexylene group or 2-methyl-l , 5-pentylene group.

6. The radically polymeri zable compound as claimed in claim 1, wherein R¹ and R² are nonylene group.

7. The radically polymeri zable compound as claimed in claim 1 represented by formula (8), wherein R¹ represents R⁴, R² represents R⁵, and X¹ and X² are 1,4- cyclohexylene group

(in the formula, R⁴ and R⁵ independently represent - (CH₂)₆- or - (CH₂) ₂CH (CH₃) (CH₂)₂-, and n and m represent arbitrary positive integer) .

8. A radically curable composition comprising radically polymeri zable compound containing terminal groups represented by formula (1)

and having a structure represented by formula (3)

(in the formula, R¹ and R² independently represent an alkylene group having 2 to 20 carbon atoms which may have an alkyl branch; X² represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group; and n and m represent an arbitrary positive integer) ; and having a number average molecular weight of 500 to 50,000; a radically polymeri zable compound having allyloxycarbonyl group (CH₂=CH-CH₂-0-CO-) or allyloxycarbonyloxy group (CH₂=CH- CH₂-0-C0-0-) at its terminal; and a radical

polymerization initiator.

9. The radically curable composition as claimed in claim 8, wherein a radically polymerizable compound having allyloxycarbonyl group at its terminal is a condensate of dicarboxylic acid diallyl ester and/or dicarboxylic acid diallyl ester and polyalcohol.

10. A method for producing the radically

polymeri zable compound claimed in any of claims 1 to 6 by subjecting a compound represented by formula (10)

(in the formula, X⁴ represents a cycloalkylene group having 5 to 10 carbon atoms which may have a substituent group or an alkylene group having 2 to 10 carbon atoms which may have a substituent group) and polycarbonate diol to transesterificat ion in the presence of a

catalyst .

11. The method for producing a radically

polymerizable compound as claimed in claim 10, wherein the catalyst is at least one member selected from the group consisting of tetraisopropoxy titanium,

tetrabutoxy titanium, dibutyltin oxide, dioctyltin oxide, hafnium acetylacetonat e and zirconium acetylacet onat e .

12. The method for producing a radically

polymerizable compound as claimed in claim 10 or 11, wherein the reaction is performed at a temperature lower than 180°C.

13. An optical material obtained by curing the radically curable composition claimed in claim 8.

14. An optical film, optical sheet, optical waveguide, optical lens, optical encapsulant, optical adhesive or light guide plate using the optical material claimed in claim 13.