JP2005239743A - Phenolic novolak resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a phenolic novolak resin which exhibits relaxed crystallinity resulting from a mesogen structure of biphenyl and is easy to handle at its low melting point. <P>SOLUTION: This phenolic novolak resin contains at least 65% of a compound represented by formula (2) (wherein (n) is 0) which is obtained by reacting a phenolic compound with one of isomers (excluding 4,4'-isomer) of formula (1) or a mixture of isomers of formula (1). In formula (1), X is a 1-4C alkoxyl group or a halogen group. In formula (2), R is hydrogen or a 1-4C alkyl group. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a phenol novolak resin obtained by reacting each isomer of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl or an isomer mixture of the compound with phenols. The phenol novolac resin of the present invention can be used as a raw material for epoxy resin curing agents, epoxidized novolac resins, urethane resins by isocyanate conversion, triazine resins, polyester resins, and the like.

Conventionally, regarding phenol novolak resins obtained by reacting isomers of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl or a mixture of isomers of the compounds with phenols, 4,4′-bisalkyl is used. A phenol novolac resin using a biphenyl derivative is disclosed (for example, see Patent Document 1 or 2). In the literature 1 or 2, a resin having a polymerization degree n = 0 is obtained, but it is assumed that it is due to a 4,4′-substituted type biphenyl skeleton, but the softening point of the resin exceeds 100 ° C. The workability is not enough.
Further, a phenol novolak condensate obtained by reacting each isomer of a bis (methoxymethyl) biphenyl compound or a mixture thereof with a phenol compound is disclosed (for example, see Patent Documents 3 and 4). Also in the literature 2 or 3, the glass transition temperature is as high as 130 ° C. or higher.
The biphenyl-crosslinked phenol novolac resin is a crystalline compound having a relatively high melting point (or glass transition temperature), and therefore requires a high temperature when used in various applications due to its high melting temperature. There is a problem in workability when used for each application, and a phenol novolac resin suitable for handling at a lower temperature is required.

Japanese Patent No. 3403178 JP 09-255603 A Japanese Patent Laid-Open No. 08-143648 Japanese Patent Laid-Open No. 11-071451

  An object of the present invention is to provide a phenol novolac resin that relaxes the crystallinity derived from the mesogenic structure of biphenyl and solves the ease of handling at a low melting point.

The subject of the present invention is
65% or more of n = 0 isomers of general formula (2) consisting of phenols and isomers of general formula (1) (excluding 4,4′-isomers) or isomer mixtures of general formula (1) It is solved by the contained phenol novolac resin.

（但し、Ｘは、炭素数１〜４までのアルコキシ基またはハロゲン基を示す。）

(However, X shows a C1-C4 alkoxy group or a halogen group.)

（但し、Ｒ−は水素または炭素数１〜４までのアルキル基を示す。）
好ましくは、
一般式（１）の異性体混合物とからなるフェノールノボラック樹脂により解決され、
さらに好ましくは、一般式（１）の異性体混合物が、少なくとも４、４’−体を４０〜７０モル％含有することからなるフェノールノボラック樹脂により解決される。
なお、ここで、４，４’−体とは、４，４’−ビス（アルコキシメチル）ビフェニルあるいは４，４’−ビス（ハロゲン化メチル）ビフェニルの総称をあらわし、２，４’−体とは２，４’−ビス（アルコキシメチル）ビフェニルあるいは２，４’−ビス（ハロゲ化メチル）ビフェニルの、２，２’−体は、２，２’−ビス（アルコキシメチル）ビフェニルあるいは２，２’−ビス（ハロゲ化メチル）ビフェニルの総称をそれぞれあらわす。

(However, R- represents hydrogen or an alkyl group having 1 to 4 carbon atoms.)
Preferably,
Solved by a phenol novolac resin consisting of an isomer mixture of general formula (1),
More preferably, the isomer mixture of the general formula (1) is solved by a phenol novolac resin comprising at least 4,4′-isomer in an amount of 40 to 70 mol%.
Here, the 4,4′-form is a generic name for 4,4′-bis (alkoxymethyl) biphenyl or 4,4′-bis (halogenated methyl) biphenyl, Is 2,4′-bis (alkoxymethyl) biphenyl or 2,4′-bis (halogenated methyl) biphenyl, and the 2,2′-form is 2,2′-bis (alkoxymethyl) biphenyl or 2,2 '-Bis (halogenated methyl) biphenyl is a generic term for each.

  The phenol novolac resin of the present invention is an amorphous resin, and can be kept at a softening point temperature of 70 ° C. or lower, has good workability for use in the above-mentioned applications, and each obtained resin. Exhibits excellent heat resistance, and also has a high level of water absorption, mechanical properties, adhesive properties, flame retardancy, and the like.

  The present invention is described in detail below.

  The phenols used in the present invention are phenols having one hydroxyl group in the benzene ring and derivatives thereof, and ordinary commercial products are used as they are. Examples of phenols other than phenol include metacresol, paracresol, xylenol, and trimethylphenol. Examples of xylenol include 2,3-xylenol and 2,4-xylenol. 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, and 3,5-xylenol isomers. These phenols can be used alone or in combination of two or more without any problem.

  Examples of the isomers of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl represented by the formula (1) of the present invention include, for example, 2,2′-isomer excluding 4,4′-isomer, Examples include 2,4′-isomers.

ここで、アルコキシ基は、炭素数が１〜４の脂肪族直鎖の炭化水素のアルコキシ基が好ましく、具体的には、メトキシ基、エトキシ基、プロポキシ基、ブトキシ基が挙げられ、取り扱いからメトキシ基が主に使用される。
ハロゲンとしては、フッ素、塩素、臭素、ヨウ素基が上げられるが、塩素が好ましく使用される。
また、上記ビス（アルコキシメチル）ビフェニルあるいはビス（ハロゲン化メチル）ビフェニルの混合物としては、例えば、４，４’−体を含む、２，２’−体、２，４’−体の各異性体からなる２種以上の異性体混合物を挙げることができる。

Here, the alkoxy group is preferably an aliphatic linear hydrocarbon alkoxy group having 1 to 4 carbon atoms. Specific examples include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. The group is mainly used.
Examples of the halogen include fluorine, chlorine, bromine and iodine groups, and chlorine is preferably used.
Examples of the mixture of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl include isomers of 2,2′-isomer and 2,4′-isomer, including 4,4′-isomer, for example. And a mixture of two or more isomers.

The isomer mixture of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl in the present invention is not particularly limited with respect to the combination and amount used, but the 4,4′-isomer is contained as a main component. The case is preferred.
Specifically, the 4,4′-form is 35 to 80 mol%, more preferably 40 to 70 mol%. If the ratio of the 4,4′-form is less than 40 mol%, the resulting resin may not exhibit sufficient heat resistance and flame retardancy, and the 4,4′- When the ratio of the body exceeds 80 mol%, the influence of crystallization appears strongly, resulting in poor workability.
In this case, the other isomers 2,2′-isomer and 2,4′-isomer are used in a proportion of 10 to 40 mol% for 2,2′-isomer and 5 to 40 mol for 2,4′-isomer. % Range is preferred.

A feature of the present invention is that a component having a polymerization degree n = 0 of a phenol novolak resin composed of phenols and isomers of the general formula (1) or a mixture thereof is 65% or more.
The component of n = 0 was obtained by measuring the obtained phenol novolac resin by gel permeation chromatographic analysis (GPC analysis), and the numerical value represents the area of the corresponding component as the area of all components. The value divided by the above is expressed in 100 minutes.
If the component of the phenol novolak resin having a degree of polymerization n = 0 is less than 65%, the influence of crystallinity may be exerted and workability may be hindered.

  In the present invention, the phenol novolac resin is produced by polycondensing phenols and bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl isomers or a mixture thereof in the presence of an acid catalyst, for example. be able to.

  The specific production conditions for the phenol novolac resin are as follows. For the blending ratio of the isomer mixture of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl, which is a crosslinkable group with phenol, The total amount of the bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl isomer may be at least 8 times mol. Preferably it is 9-50 times mole, More preferably, it is 10-30 times mole. When the amount is less than 8 times mol, crosslinking proceeds and a phenol novolac resin suitable for the purpose cannot be stably obtained. If it is too much, there are many unreacted raw materials, which is not economical.

  Examples of the acid catalyst used in the present invention include organic acids such as paratoluenesulfonic acid and dimethyl sulfate, and inorganic acids such as hydrochloric acid and sulfuric acid. The amount of the catalyst used is suitably in the range of 0.01 to 1% by weight with respect to the phenols. If the amount is too small, the reaction rate may be slow, and if it is too large, the reaction may proceed rapidly and it may be difficult to control the reaction.

  The reaction temperature varies depending on the phenols used and the blending ratio of each isomer of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl as a crosslinking group or a mixture thereof, but usually 50 to 200 ° C., preferably It is 70-180 degreeC, More preferably, it is 80-180 degreeC. If it is too low, polymerization does not proceed. If it is too high, it becomes difficult to control the reaction, and it becomes difficult to stably obtain the desired phenol novolac resin.

  The reaction time depends on the reaction temperature, but is usually within 10 hours.

  The reaction pressure is usually carried out under normal pressure, but it can also be carried out under slight pressure or reduced pressure.

  The phenol novolac resin obtained by the production method of the present invention exhibits excellent fluidity and curing characteristics as a curing agent such as an epoxy resin, and provides a cured resin product having excellent heat resistance. Moreover, it is a resin composition which can be suitably used as a raw material for an epoxidized novolac resin, a urethane resin by isocyanate conversion, a triazine resin, or the like.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In addition, a part shows a weight part.
Moreover, the content of the component and the analysis method of the resin are as follows.
(1) (Gel permeation chromatographic analysis: GPC measurement method)
Model: HLC-8220 Tosoh Co., Ltd. Column: TSK-GEL H type G2000H × L 4
1 G3000H x L
G4000H × L One measurement condition: Column pressure 13.5 MPa
Eluent: Tetrahydrofuran (THF) flow rate 1 ml / min
Temperature: 40 ° C
Detector Spectrophotometer (UV-8020) RANGE 2.56
WAVE LENGTH 254nm and RI
(2) Measurement of OH equivalent A sample of 2 to 3 g was acetylated with 1.25 g of acetic anhydride, and acetic acid after acetylation was titrated with potassium hydroxide to obtain an OH equivalent. (Acetylation method)
(3) Determined by the softening point ring and ball method.

Example 1
To a glass flask having a capacity of 2000 parts by volume equipped with a thermometer, a charging / distilling outlet and a stirrer, 940 parts (10 moles) of phenol, 2,2′-bis (methoxymethyl) biphenyl (abbreviated as 2,2′-BMMB) 87.1 parts (0.36 mol), 2,4′-bis (methoxymethyl) biphenyl (abbreviated as 2,4′-BMMB) 58.1 parts (0.24 mol), 4,4 ′ -96.8 parts (0.40 mol) of bis (methoxymethyl) biphenyl (abbreviated as 4,4'-BMMB) and 2.4 parts of 25% sulfuric acid aqueous solution were added, and the mixture was stirred at 120 ° C to 160 ° C. The reaction was carried out at 5 hours at 160 ° C. for 2 hours.
Thereafter, steaming was performed under a reduced pressure of 760 mmHg under steam conditions of 1.3 KPa and 160 ° C. for 2 hours. Thereafter, dehydration was performed at 1.3 KPa and 160 ° C. for 1 hour under a reduced pressure of 760 mmHg to obtain a phenol novolac resin. As a result of gas chromatography analysis (GC measurement), the free phenol component of the obtained phenol novolak resin was 0.2% by weight. As a result of gel permeation chromatography analysis (GPC measurement), the ratio of n = 0 isomers was 68%, and the average molecular weight was 497.
The softening point by the ring and ball method was 63 ° C.
Here, the physical properties of the obtained phenol novolac resin are shown in Table 1.

Example 2
Into a glass flask having a capacity of 2000 parts by volume equipped with a thermometer, a charging / distilling outlet and a stirrer, phenol 1688 parts (18 mol), 2,2′-bis (chloromethyl) biphenyl (2,2′-BCMB) and (Abbreviated) 30.1 parts (0.12 mol), 2,4′-bis (chlorinated methyl) biphenyl (abbreviated 2,4′-BCMB) 45.2 parts (0.18 mol), 4, 175.7 parts (0.70 mol) of 4′-bis (chlorinated methyl) biphenyl (abbreviated as 4,4′-BCMB) and 1.4 parts of 25% aqueous sulfuric acid solution were added, and the mixture was heated at 120 ° C. to 160 ° C. The reaction was allowed to proceed for 2 h at 160 ° C. for 5 h.
Thereafter, steaming was performed under a reduced pressure of 760 mmHg under steam conditions of 1.3 KPa and 160 ° C. for 2 hours. Thereafter, dehydration was performed at 1.3 KPa and 160 ° C. for 1 hour under a reduced pressure of 760 mmHg to obtain a phenol novolac resin. As a result of gas chromatographic analysis (GC measurement), the free phenol component of the obtained phenol novolac resin was 0.3% by weight. As a result of gel permeation chromatography analysis (GPC measurement), the ratio of n = 0 isomers was 75%, and the average molecular weight was 470.
The softening point by the ring and ball method was 61 ° C.
Here, the physical properties of the obtained phenol novolac resin are shown in Table 1.

Examples 3 and 4
The compounds shown in Table 1 were synthesized according to Example 1.
The physical properties of the obtained phenol novolac resin are also shown in Table 1.

Comparative Examples 1-3
The compounds shown in Table 1 were synthesized according to Example 1.
Furthermore, the physical property characteristic of the obtained phenol novolak resin was combined with Table 1, and was shown.

(Results of using the resin obtained in the present invention as a curing agent for epoxy resin)
Each phenol novolak resin in Table 1 (hydroxyl equivalent: 190 g / eq) was used.
Moreover, NC3000P (softening point 150 ° C., epoxy equivalent 272 g / eq) manufactured by Nippon Kayaku Co., Ltd. is used as the epoxy resin, and RD-8 manufactured by Tatsumori Chemical Co., Ltd. is used as the filler. Triphenylphosphine was used as a curing accelerator.
Each component in Table 1 is blended at the same equivalent ratio as the above epoxy resin, heated to 150 ° C., melt mixed, poured into a 150 ° C. mold (thickness 4 mm) after vacuum defoaming, and cured (150 ° C., After 3 hours curing, it was cured at 180 ° C. for 5 hours). Flame resistance was evaluated by a flame resistance test UL-94 vertical test (sample thickness 1.5875 mm (1/16 inch)).

GPC chart of Example 1

Claims (4)

65% or more of n = 0 isomers of general formula (2) consisting of phenols and isomers of general formula (1) (excluding 4,4′-isomers) or isomer mixtures of general formula (1) Contains phenol novolac resin.

(However, X shows a C1-C4 alkoxy group or a halogen group.)

(However, R- represents hydrogen or an alkyl group having 1 to 4 carbon atoms.)
  The phenol novolac resin according to claim 1, comprising a mixture of isomers of the general formula (1).   The phenol novolak resin according to claim 2, wherein the isomer mixture of the general formula (1) contains at least 4,4'-isomer in an amount of 35 to 80 mol%. The phenol novolac resin according to any one of claims 1 to 3, wherein a softening point temperature of the general formula (2) is 70 ° C or lower.

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