JP6164929B2 - Vinyl ether resin compound containing carbonate skeleton - Google Patents

Description

  The present invention relates to a carbonate skeleton-containing vinyl ether resin compound.

  Since polyvinyl ether is excellent in flexibility, it is used in various adhesives, ink compositions, coating films, lubricating oils, electrical component materials, optical materials, and medical materials.

  Although the coating film containing polyvinyl ether has excellent flexibility, it has been difficult to maintain the strength for practical use. In order to improve the strength of a coating film containing polyvinyl ether, studies on the main chain structure of polyvinyl ether have been proposed.

  Patent Document 1 discloses a coating film containing a polyvinyl ether composition containing an ether skeleton. In general, a coating film containing a polyvinyl ether composition containing an ether skeleton has flexibility, hydrolysis resistance, and stretchability.

  Patent Document 2 discloses a polyvinyl ether composition containing an ester skeleton. The composition containing this ester skeleton has characteristics of toughness, heat resistance, and weather resistance when used in coating applications.

Japanese Patent No. 2843767 Japanese Patent No. 3115317

However, the coating film obtained by photocuring after applying the composition described in Patent Document 1 to a substrate has a problem that the elongation property is small and the strength of the film is small. This is presumably because the ether part of the ether skeleton of this composition has no strength.
Furthermore, when the cured product of this composition is polymerized to obtain strength, there is a problem that flexibility (flexibility) and elongation characteristics become insufficient.
In addition, the composition having an ester skeleton described in Patent Document 2 exhibits higher strength than a composition having an ether skeleton, but the strength of the coating film is not sufficient because the vinyl ether portion has flexibility. was there.
Furthermore, when the cured product of this composition is polymerized to obtain strength, there is a problem that flexibility (flexibility) and elongation characteristics become insufficient.

  The present inventor has developed a novel carbonate skeleton-containing vinyl ether resin compound in order to obtain a coating film having excellent elongation characteristics and strength. Furthermore, the present inventor has found that the resin compound has both excellent elongation characteristics and strength by using this resin compound for coating applications, and has completed the present invention.

  An object of the present invention is to provide a carbonate skeleton-containing vinyl ether resin compound having excellent elongation characteristics and strength when used in a coating film.

  As a result of earnest research to achieve the above problems, the present inventors have found that when the following carbonate skeleton-containing vinyl ether resin compound is used for a coating film, it has excellent elongation characteristics and strength at the same time. The present invention has been completed. That is, this invention includes the following aspects.

[1] A carbonate skeleton-containing vinyl ether resin compound represented by the formula (1).

［式（１）中、−Ｘ¹−、−Ｘ²−は、それぞれ独立に、−Ｃ_４Ｈ_８−、−Ｃ_２Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ₂Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ_２Ｈ_４ＯＣ_２Ｈ_４−、−Ｃ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６ＯＣ_３Ｈ_６−または式（２）の置換基を表す。式（１）中、−Ｚ−は、式（３）の置換基を表す。式（１）中、−Ｒ−は、炭素数３〜５０の直鎖状炭化水素基、分岐鎖状炭化水素基および環状炭化水素基からなる群より選ばれる少なくとも一つの炭化水素基を表す。−Ｒ−は、構成する原子にヘテロ原子を含んでもよい。また、ｎは、正の整数を表す。］

Wherein ^{(1), -X 1 -,} - X 2 - are each _{independently, -C 4 H 8 -, -} C 2 H 4 -, - C 2 H 4 OC 2 H 4 -, - C 2 _{H 4 OC 2 H 4 OC 2} H 4 -, - C 3 H 6 -, - C 3 H 6 OC 3 H 6 -, - C 3 H 6 OC 3 H 6 OC 3 H 6 - or formula (2) Represents a substituent. In formula (1), -Z- represents a substituent of formula (3). In formula (1), -R- represents at least one hydrocarbon group selected from the group consisting of a linear hydrocarbon group having 3 to 50 carbon atoms, a branched hydrocarbon group and a cyclic hydrocarbon group. -R- may contain a hetero atom in the constituent atoms. N represents a positive integer. ]

[2] Carbonate skeleton containing according to [1] obtained by reaction of carbonate diol represented by molecular formula (a), diisocyanate represented by molecular formula (b) and hydroxyl group-containing vinyl ether monomer represented by molecular formula (c) Vinyl ether resin compound.

［式（a）中、−Ｒ−は、炭素数３〜５０の直鎖状炭化水素基、分岐鎖状炭化水素基および環状炭化水素基からなる群より選ばれる少なくとも一つの炭化水素基を表す。−Ｒ−は、構成する原子の一部にヘテロ原子を含んでもよい。また、ｎは、正の整数を表す。］

[In the formula (a), -R- represents at least one hydrocarbon group selected from the group consisting of a linear hydrocarbon group having 3 to 50 carbon atoms, a branched hydrocarbon group and a cyclic hydrocarbon group. . -R- may contain a hetero atom as part of the constituent atoms. N represents a positive integer. ]

［式（c）中、−Ｘ−は、−Ｃ_４Ｈ_８−、−Ｃ_２Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ₂Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ_２Ｈ_４ＯＣ_２Ｈ_４−、−Ｃ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６ＯＣ_３Ｈ_６−または式（３）の置換基を表す。］

Wherein (c), -X- _{is, -C 4 H 8 -, -} C 2 H 4 -, - C 2 H 4 OC 2 H 4 -, - C 2 H 4 OC 2 H 4 OC 2 H 4 _{-, - C 3 H 6 -} , - C 3 H 6 OC 3 H 6 -, - , or a substituted group of the formula _{(3) - C 3 H 6} OC 3 H 6 OC 3 H 6. ]

[3] The carbonate skeleton-containing vinyl ether resin compound according to [1] or [2], wherein the weight average molecular weight is in the range of 700 to 50,000.

  ADVANTAGE OF THE INVENTION According to this invention, when used for a coating film, the carbonate skeleton containing vinyl ether-type resin compound which has the outstanding elongation characteristic and intensity | strength simultaneously can be provided.

  Hereinafter, the carbonate skeleton-containing vinyl ether resin compound of the present invention will be described in detail. In this specification, the carbonate skeleton-containing vinyl ether resin compound may be simply referred to as a resin compound.

  The resin compound of the present invention is a carbonate skeleton-containing vinyl ether resin compound represented by the formula (1).

［式（１）中、−Ｘ¹−、−Ｘ²−は、それぞれ独立に、−Ｃ_４Ｈ_８−、−Ｃ_２Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ₂Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ_２Ｈ_４ＯＣ_２Ｈ_４−、−Ｃ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６ＯＣ_３Ｈ_６−または式（２）の置換基を表す。式（１）中、−Ｚ−は、式（３）の置換基を表す。式（１）中、−Ｒ−は、炭素数３〜５０の直鎖状炭化水素基、炭素数３〜５０の分岐鎖状炭化水素基および炭素数３〜５０の環状炭化水素基からなる群より選ばれる少なくとも一つの炭化水素基を表す。−Ｒ−は、構成する原子にヘテロ原子を含んでもよい。また、ｎは、正の整数を表す。］

Wherein ^{(1), -X 1 -,} - X 2 - are each _{independently, -C 4 H 8 -, -} C 2 H 4 -, - C 2 H 4 OC 2 H 4 -, - C 2 _{H 4 OC 2 H 4 OC 2} H 4 -, - C 3 H 6 -, - C 3 H 6 OC 3 H 6 -, - C 3 H 6 OC 3 H 6 OC 3 H 6 - or formula (2) Represents a substituent. In formula (1), -Z- represents a substituent of formula (3). In the formula (1), -R- is a group consisting of a linear hydrocarbon group having 3 to 50 carbon atoms, a branched hydrocarbon group having 3 to 50 carbon atoms and a cyclic hydrocarbon group having 3 to 50 carbon atoms. It represents at least one hydrocarbon group selected from the above. -R- may contain a hetero atom in the constituent atoms. N represents a positive integer. ]

  The resin compound (1) of the present invention has two vinyl ether groups. Therefore, a coating film can be easily obtained by applying a resin composition containing the resin compound (1) of the present invention and a photopolymerization initiator to a substrate and then irradiating with light.

The resin compound (1) of the present invention comprises a carbonate diol represented by the following molecular formula (a), a diisocyanate represented by the molecular formula (b), and a hydroxyl group-containing vinyl ether monomer represented by the molecular formula (c). Obtained by reaction. In the reaction, when one hydroxyl group-containing vinyl ether monomer represented by the molecular formula (c) is used, -X ¹ -and -X ^2- in the formula (1) are the same in the resin compound (1) of the present invention. Become.

［式（a）中、−Ｒ−は、炭素数３〜５０の直鎖状炭化水素基、炭素数３〜５０の分岐鎖状炭化水素基および炭素数３〜５０の環状炭化水素基からなる群より選ばれる少なくとも一つの炭化水素基を表す。−Ｒ−は、構成する原子の一部にヘテロ原子を含んでもよい。また、ｎは、正の整数を表す。］

[In Formula (a), -R- consists of a C3-C50 linear hydrocarbon group, a C3-C50 branched hydrocarbon group, and a C3-C50 cyclic hydrocarbon group. Represents at least one hydrocarbon group selected from the group; -R- may contain a hetero atom as part of the constituent atoms. N represents a positive integer. ]

［式（c）中、−Ｘ−は、−Ｃ_４Ｈ_８−、−Ｃ_２Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ₂Ｈ_４−、−Ｃ_２Ｈ_４ＯＣ_２Ｈ_４ＯＣ_２Ｈ_４−、−Ｃ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６−、−Ｃ_３Ｈ_６ＯＣ_３Ｈ_６ＯＣ_３Ｈ_６−または式（３）の置換基を表す。］

Wherein (c), -X- _{is, -C 4 H 8 -, -} C 2 H 4 -, - C 2 H 4 OC 2 H 4 -, - C 2 H 4 OC 2 H 4 OC 2 H 4 _{-, - C 3 H 6 -} , - C 3 H 6 OC 3 H 6 -, - , or a substituted group of the formula _{(3) - C 3 H 6} OC 3 H 6 OC 3 H 6. ]

  Since the resin compound (1) of the present invention has a carbonate skeleton as shown by the molecular formula (a), it has high strength and high heat resistance. Also, as shown by the molecular formula (b), the diisocyanate having an isophorone skeleton. Since it has a structure, it has high strength, and furthermore, since it has a hydroxyl group-containing vinyl ether monomer structure as shown in the molecular formula (c), it has flexibility and fast curability.

The weight average molecular weight of the resin compound (1) used in the present invention, 7 98 50,000, it is preferably preferably from 7 98 10,000 range. When the resin compound (1) has a weight average molecular weight of 50,000 or more, the carbonate skeleton of the resin compound (1) increases the crystallinity and increases the viscosity. Therefore, during the production of the resin compound (1), the resin compound (1) Handling of 1) becomes difficult. The weight average molecular weight of the resin compound (1) used in the present invention can be calculated by a standard polystyrene conversion method using gel permeation chromatography (hereinafter abbreviated as GPC).

  The coating film obtained by applying a resin composition containing the resin compound (1) of the present invention and a photopolymerization initiator to a base material such as a polypropylene film and then photocuring has excellent elongation characteristics. And the strength of the coating film is high.

Photopolymerization initiators that can be suitably used in the present invention include, for example, arylsulfonium salt derivatives (Syracure UVI-6990, Syracure UVI-6974, manufactured by Dow Chemical Co., Ltd .; Adekaoptomer SP-150, ADEKATOPO manufactured by ADEKA, Inc. Mer-SP-152, Adekaoptomer SP-170, Adekaoptomer SP-172; CPI-100P, CPI-110P, CPI-110A, CPI-210S manufactured by San Apro Co., Ltd. TS-91, TS manufactured by Sanwa Chemical Co., Ltd. -01; BASF Irgacure PAG270, PAG290, GSID26-1; Lamberti Esacure 1187, Esacure 1188, etc.), allyl iodonium salt derivatives (Rhodia PHOTOINITIATOR 2074; BA Irgacure PAG250 manufactured by F Co., Ltd.), oxime sulfonic acid derivatives (Irgacure PAG103, PAG108, PAG121, PAG203, CGI725, CGI1905, CGI1906, CGI1906 manufactured by BASF), allene-ion complex derivative, diazonium salt derivative, triazine initiator And other acid generators such as halides.
In addition, since it shows excellent curability and can suppress the odor of the resulting coating film, photopolymerization initiators that can be used particularly preferably in the present invention are CPI-100P and CPI-110P manufactured by San Apro. (Diphenyl [4- (phenylthio) phenyl] sulfonium hexafluorophosphate), CPI-210S (phosphorus anion-containing triarylsulfonium salt), TS-91 (Tris (4-methylphenyl) sulfonium hexa) manufactured by Sanwa Chemical Co., Ltd. Fluorophosphate), Irgacure PAG290 manufactured by BASF, and PHOTOINITIATOR 2074 manufactured by Rhodia.

  The resin composition containing the resin compound (1) of the present invention may contain a vinyl ether monomer other than the resin compound (1). Such vinyl ether monomers include, for example, ethyl vinyl ether, n-butyl vinyl ether, i-butyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexane dimethanol monovinyl ether, n-propyl vinyl ether. , Isopropyl vinyl ether, isopropenyl ether-o-propylene carbonate, dodecyl vinyl ether, ethylene glycol monovinyl ether, diethylene glycol monovinyl ether, triethylene glycol monovinyl ether, octadecyl vinyl ether, ethylene glycol divinyl ether, diethylene glycol divinyl ether Ter, triethylene glycol divinyl ether, tetraethylene glycol divinyl ether, pentaethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, tripropylene glycol divinyl ether, 1,4-butanediol divinyl ether, hexanediol divinyl ether Is mentioned.

  The resin composition containing the resin compound (1) of the present invention has various resins, leveling agents, antifoaming agents, light stabilizers, antioxidants, ultraviolet absorbers, flame retardants, and polymerizations as long as the effects of the invention are not impaired. An inhibitor, an antistatic agent, a silane coupling agent, a sensitizer, and the like can be contained.

  The resin composition containing the resin compound (1) of the present invention becomes a coating film having elongation characteristics and a high film strength by being photocured after being applied to a substrate such as a polypropylene film. Therefore, the resin compound of the present invention is useful as a coating film.

  EXAMPLES Hereinafter, although an Example shows this invention concretely, this invention is not limited at all by these Examples.

  The weight average molecular weight (hereinafter abbreviated as Mw) of the resin compound of the present invention was calculated and obtained by a standard polystyrene conversion method using GPC. Mw is a differential refractometer (RI) with HLC-8220 GPC (manufactured by Tosoh Corporation) as a GPC analysis system apparatus and TSKgel SuperMultipore HZ-H (manufactured by Tosoh Corporation) connected in series as a column. (Established by Tosoh Corporation HLC-8220 apparatus) was obtained under the condition of a column temperature of 40 ° C. using tetrahydrofuran (flow rate 0.35 mL / min) as a mobile phase.

Example 1
[Synthesis of carbonate skeleton-containing vinyl ether resin compound]
In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 100 parts by mass of Plaxel CD205PL (manufactured by Daicel Corporation: polycarbonate diol), 92 parts by mass of isophorone diisocyanate, and 0.03 parts by mass of dibutyltin dilaurate were placed under stirring. The temperature of the contents of the reaction vessel was raised to 60 ° C. and reacted for 2 hours. Thereafter, 0.21 part by mass of dibutyltin dilaurate and 46 parts by mass of 4-hydroxybutyl vinyl ether (HBVE) were added, and the mixture was further reacted for 2 hours. The completion of the reaction was confirmed by taking out a part of the reaction solution and disappearing the 2250 cm ⁻¹ peak derived from isocyanate in the infrared absorption spectrum (IR). Thus, a resin compound that was a transparent liquid was obtained. The Mw of the resin compound was 2,100.

(Example 2)
[Synthesis of carbonate skeleton-containing vinyl ether resin compound]
In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 100 parts by mass of Kuraray polyol C-590 (manufactured by Kuraray Co., Ltd .: polycarbonate diol), 90 parts by mass of isophorone diisocyanate, 0.03 parts by mass of dibutyltin dilaurate, Under stirring, the temperature of the contents of the reaction vessel was raised to 60 ° C. and reacted for 2 hours. Thereafter, 0.17 parts by mass of dibutyltin dilaurate and 44 parts by mass of 4-hydroxybutyl vinyl ether (HBVE) were added, and the reaction was further continued for 2 hours. The completion of the reaction was confirmed by taking out a part of the reaction solution and disappearing the 2250 cm ⁻¹ peak derived from isocyanate in the infrared absorption spectrum (IR). Thus, the resin compound which is a transparent liquid was obtained. The Mw of the resin compound was 2,000.

(Comparative Example 1)
[Synthesis of a caprolactone diol compound having a vinyl ether group at the terminal]
In a reaction vessel equipped with a thermometer, a stirrer and a reflux condenser, 100 parts by mass of polycaprolactone diol (trade name PLACEL 210CP, manufactured by Daicel Corporation), 44.7 parts by mass of isophorone diisocyanate, and 0.01 parts by mass of dibutyltin dilaurate were added. While stirring, the temperature of the contents of the reaction vessel was raised to 60 ° C. and reacted for 2 hours. Thereafter, 0.09 parts by mass of dibutyltin dilaurate and 22.2 parts by mass of 4-hydroxybutyl vinyl ether were added, and the reaction was further continued for 2 hours. After cooling, a caprolactone diol compound that was a transparent liquid was obtained.
The completion of the reaction was confirmed by removing a part of the reaction solution and disappearing the 2250 cm ⁻¹ peak derived from isocyanate in the infrared absorption spectrum (IR). The Mw of the caprolactone diol compound was 3,200.

(Comparative Example 2)
[Synthesis of a polytetramethylene glycol compound having a vinyl ether group at the terminal]
In a reaction vessel equipped with a thermometer, a stirrer and a reflux condenser, 100 parts by mass of polytetramethylene glycol (trade name PTMG1000 manufactured by Mitsubishi Chemical Corporation), 44.4 parts by mass of isophorone diisocyanate, and 0.01 parts by mass of dibutyltin dilaurate The contents of the reaction vessel were heated to 60 ° C. with stirring and reacted for 2 hours. Thereafter, 0.09 parts by mass of dibutyltin dilaurate and 22.1 parts by mass of 4-hydroxybutyl vinyl ether were added and further reacted for 2 hours. After cooling, a polytetramethylene glycol compound that was a transparent liquid was obtained.
The completion of the reaction was confirmed by removing a part of the reaction solution and disappearing the 2250 cm ⁻¹ peak derived from isocyanate in the infrared absorption spectrum (IR). The Mw of the polytetramethylene glycol compound was 4,040.

(Comparative Example 3)
[Synthesis of a polypropylene glycol compound having a vinyl ether group at the terminal]
In a reaction vessel equipped with a thermometer, a stirrer and a reflux condenser, 100 parts by mass of polypropylene glycol (trade name Sannix PP-400, manufactured by Sanyo Chemical Co., Ltd.), 110 parts by mass of isophorone diisocyanate, and 0.04 parts by mass of dibutyltin dilaurate The contents of the reaction vessel were heated to 60 ° C. with stirring and reacted for 2 hours. Thereafter, 0.21 part by mass of dibutyltin dilaurate and 54 parts by mass of 4-hydroxybutyl vinyl ether were added and further reacted for 2 hours. After cooling, 264 parts by mass of a polypropylene glycol compound was obtained as a transparent liquid.
The completion of the reaction was confirmed by removing a part of the reaction solution and disappearing the 2250 cm ⁻¹ peak derived from isocyanate in the infrared absorption spectrum (IR). Mw of the polypropylene glycol compound was 1,700.

(Preparation of coating film)
The coating film is a composition obtained by blending a carbonate skeleton-containing vinyl ether resin compound of each example and a compound of each comparative example with a photopolymerization initiator (trade name CPI-210S, manufactured by San Apro Co., Ltd.) in the formulation shown in Table 1. Was prepared. Next, this composition was coated on a polypropylene film using an applicator having a coating thickness of 90 μm, cured using a high-pressure mercury lamp with an irradiation intensity of 160 W under the condition of an irradiation dose of 1000 mJ / cm ² , and then peeled off from the polypropylene film Thus, a coating film was prepared. The obtained coating film had a thickness of 70 to 80 μm.

(Tensile strength test)
According to JIS K7127, elongation (%) and strength (MPa) were measured under the condition of a tensile speed of 10 mm / min. The coating film was cut into a strip shape having a width of 15 mm to prepare a test piece. The elongation and strength of the test piece were measured under the condition that the distance between chucks was 25 mm.
A coating film having an elongation of 90% or more and a strength of 10 MPa or more was evaluated as ◯, and an elongation of less than 90% or a strength of less than 10 MPa was evaluated as x.

Table 1 shows the blending of the resin compounds of the examples and the compounds of the comparative examples, measured values of elongation (elongation) and strength of the coating film containing these compounds, and determination results.
According to the evaluation result of each Example shown in Table 1, it was confirmed that the resin coating film containing the resin compound of the present invention has both excellent elongation characteristics and strength.
On the other hand, as shown in the comparative example, the coating film containing the caprolactone diol compound has elongation characteristics but weak strength, and the coating film containing the polytetramethylene diisocyanate compound or the polypropylene glycol compound has elongation characteristics and strength, respectively. Therefore, the usefulness as a coating film is inferior.

  The carbonate skeleton-containing vinyl ether resin compound of the present invention is useful as a coating film because it has both elongation characteristics and strength.

Claims (2)

A resin composition comprising a carbonate skeleton-containing vinyl ether resin compound represented by formula (1) and a photoinitiator.

Wherein ^{(1), -X 1 -,} - X 2 - are each _{independently, -C 4 H 8 -, -} C 2 H 4 -, - C 2 H 4 OC 2 H 4 -, - C 2 _{H 4 OC 2 H 4 OC 2} H 4 -, - C 3 H 6 -, - C 3 H 6 OC 3 H 6 -, - C 3 H 6 OC 3 H 6 OC 3 H 6 - or formula (2) Represents a substituent. In formula (1), -Z- represents a substituent of formula (3). In formula (1), -R- represents at least one hydrocarbon group selected from the group consisting of a linear hydrocarbon group having 3 to 50 carbon atoms, a branched hydrocarbon group and a cyclic hydrocarbon group. -R- may contain a hetero atom in the constituent atoms. N represents a positive integer. ]

Carbonate skeleton-containing vinyl ether based on formula (1) obtained by reaction of carbonate diol represented by molecular formula (a), diisocyanate represented by molecular formula (b), and hydroxyl group-containing vinyl ether monomer represented by molecular formula (c) A resin composition comprising a resin compound and a photoinitiator.

[In the formula (a), -R- represents at least one hydrocarbon group selected from the group consisting of a linear hydrocarbon group having 3 to 50 carbon atoms, a branched hydrocarbon group and a cyclic hydrocarbon group. . -R- may contain a hetero atom as part of the constituent atoms. N represents a positive integer. ]

Wherein (c), -X- _{is, -C 4 H 8 -, -} C 2 H 4 -, - C 2 H 4 OC 2 H 4 -, - C 2 H 4 OC 2 H 4 OC 2 H 4 _{-, - C 3 H 6 -} , - C 3 H 6 OC 3 H 6 -, - , or a substituted group of the formula _{(3) - C 3 H 6} OC 3 H 6 OC 3 H 6. ]

Wherein ^{(1), -X 1 -,} - X 2 - are each _{independently, -C 4 H 8 -, -} C 2 H 4 -, - C 2 H 4 OC 2 H 4 -, - C 2 _{H 4 OC 2 H 4 OC 2} H 4 -, - C 3 H 6 -, - C 3 H 6 OC 3 H 6 -, - C 3 H 6 OC 3 H 6 OC 3 H 6 - or formula (2) Represents a substituent. In formula (1), -Z- represents a substituent of formula (3). In formula (1), -R- represents at least one hydrocarbon group selected from the group consisting of a linear hydrocarbon group having 3 to 50 carbon atoms, a branched hydrocarbon group and a cyclic hydrocarbon group. -R- may contain a hetero atom in the constituent atoms. N represents a positive integer. ]