JPH04328151A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain an epoxy resin composition, excellent in water and fouling resistance, moistureproofness, mold releasability, etc., while maintaining bulk characteristics such as mechanical strength and chemical resistance by blending an epoxy resin with a fluorine-containing block copolymer. CONSTITUTION:An epoxy resin composition is obtained by blending 100 pts.wt. epoxy resin with (A) 0.1-40 pts.wt. fluorine-containing block copolymer, composed of (A) structural units derived from a compound expressed by formula I [R1 is H or methyl; R2 is formula II [(p) is 1-10], etc.; Rf is formula III [(m) is 0-10; (n) is 1-16], etc.} and (B) structural units composed of a polymer part derived from a compound expressed by formula IV [R3 is H or methyl; R4 is COOR5 (R5 is H, formula V, etc.)] and 10-70wt.% polymer part composed of units expressed by formula VI (R8 is H or methyl) at (70/30)-(10/90) weight ratio of the components (A/B). The molar ratio of fluorine atoms to carbon atoms in the epoxy resin composition is 0.4-2.5.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to epoxy resin compositions used in inks and coating materials for electronic components, various electrical insulating materials such as encapsulating materials for semiconductor devices, and various heavy-duty anticorrosion paints. . More specifically, the presence of a high concentration of fluorine-containing groups on the surface of films and molded objects formed from epoxy resin compositions maintains the excellent bulk properties of epoxy resins, such as mechanical properties and heat resistance. However, the present invention relates to an epoxy resin composition that can exhibit surface properties such as water resistance and moisture resistance, as well as stain resistance and mold releasability based on fluorine-containing groups.

0002

[Prior Art] Epoxy resins have excellent properties in terms of mechanical strength, heat resistance, chemical resistance, adhesiveness, etc. These properties are used to manufacture electronic components, composite materials, paints, and adhesives. It is widely used. However, due to the relatively high surface free energy, the surface is more compatible with foreign materials. Therefore, from the viewpoint of mold releasability, it exhibits physical properties that can be said to be disadvantageous, and also has the disadvantage of being susceptible to contamination due to its tendency to adsorb organic substances. Furthermore, since it contains a hydroxyl group (OH group), it has a high affinity for water, and there are also problems in terms of water resistance and moisture resistance.

[0003] In order to solve this drawback, attempts have been made to modify the skeleton of the epoxy resin or to blend it with other resins depending on the application. Attempts have also been made to improve the above problems by adding fluorine compounds, silicon compounds, and the like. The present inventors also discovered that by using a fluorine-containing block copolymer as a surface modifier in JP-A No. 60-22410,
We propose that the functions of fluorine-containing groups can be imparted to the surface of materials.

0004

[Problems to be Solved by the Invention] However, in any of the above methods, it is difficult to improve only the surface properties while maintaining the bulk properties of the epoxy resin, and the surface modification effect and the sustainability of the modification effect are difficult to achieve. There are problems in that the epoxy resin is insufficient or the properties of the epoxy resin are deteriorated, and improvements are desired.

[0005] Also, the present inventors' proposal, JP-A-60
Although Publication No. 22410 describes a method that can impart the functions of fluorine-containing groups to the material surface, it does not provide sufficient water resistance, moisture resistance, stain resistance, or release properties while maintaining the bulk properties of the epoxy resin. In order to impart moldability, it was necessary to optimize the composition of the block copolymer, and this was at a stage that required further investigation.

The present invention has been made to solve these problems, and its purpose is to improve the water resistance and moisture resistance based on the fluorine-containing group while maintaining the bulk properties inherent to epoxy resin. In addition, it has stain resistance,
The object of the present invention is to provide an epoxy resin composition that can exhibit surface properties such as mold releasability.

[0007]

[Means for Solving the Problems] As a result of various studies, the present inventors have found that the above characteristics are achieved by a polymer portion having a specific composition that has excellent compatibility and chemical reactivity with an epoxy resin, and a fluorine-containing portion having a specific composition. The present invention was completed based on the discovery that this can be achieved with an epoxy resin composition containing a fluorine-containing block copolymer composed of a polymer portion.

That is, the first invention of the present invention provides an epoxy resin composition containing an epoxy resin and the following fluorine-containing block copolymer, wherein the content of the fluorine-containing block copolymer is 100% of the epoxy resin. The amount of fluorine is 0.1 to 40 parts by weight based on the epoxy resin composition, and the fluorine was measured with an X-ray photoelectron analyzer under the condition that the escape angle of photoelectrons from the surface of the object was 90 degrees on the surface of the object formed from the epoxy resin composition. The molar ratio of atoms to carbon atoms is 0.4~
2.5 is adopted.

Fluorine-containing block copolymer: A structural unit (A) consisting of a structural unit (A) derived from the above chemical formula 1, a polymer portion derived from the above chemical formula 2, and a polymer portion having the above chemical formula 3 as a unit. B), the proportion of the polymer portion having chemical compound 3 as a unit in the structural unit (B) is 10 to 70% by weight, and the proportion of the structural unit (A)/structural unit (B) is 70% by weight. A fluorine-containing block copolymer having a ratio of /30 to 10/90.

Further, in the second invention, the fluorine-containing block copolymer according to the first invention contains at least 40% by weight of a polymer portion derived from the above chemical formula 1 and 60% by weight of a polymer portion derived from the above chemical formula 2. A structural unit (A) consisting of % or less,
It consists of a structural unit (B) consisting of a polymer part derived from the above chemical formula 2 and a polymer part having the above chemical formula 3 as a unit, and the proportion of the polymer part having chemical formula 3 as a unit in the structural unit (B) is 10 to 70% by weight, and the weight ratio of structural unit (A)/structural unit (B) is 70/30 to 10/90.

Next, each component of the present invention will be explained. First, the structural unit (A) in the block copolymer of the present invention will be explained. In the process of forming films and molded products from the epoxy resin composition of the present invention, the fluorine-containing block copolymer is efficiently oriented on the surface, so that fluorine-containing groups are present in a high concentration on the surface, and the fluorine-containing groups Surface properties such as water resistance, moisture resistance, stain resistance, and mold releasability are developed based on

For this purpose, the structural unit (A) is
Alternatively, it is essential that the polymer consists of 40% by weight or more of a polymer derived from the above chemical formula 1 and 60% by weight or less of a polymer portion derived from the above chemical formula 2. If the structural unit (A) is composed of less than 40% by weight of the polymer portion derived from Chemical Formula 1, the above-mentioned function based on the fluorine-containing group will be insufficient.

In the above formula 1, if p and m exceed 10, the properties derived from the fluorine-containing group will decrease, which is not preferable. Furthermore, a uniter in which n and l exceed 16 is not preferred because it is not easy to synthesize and the properties derived from the fluorine-containing group are not necessarily good. p is 1 to 4, m is 0 to 4, n and l are 1
~10, and the terminal of the fluorine-containing group is -CF3
It is further preferable that

As the monomer represented by the above formula 1, the following can be used.

[0015]

[Chemical formula 4] CF3(CF2)7CH2CH2OCOCH=
H2,

[0016]

[Chemical formula 5] CF3CH2OCOCH=CH2,

0017
]

[Chemical formula 6] CF3(CF2)4CH2CH2OCOC(C
H3)=CH2,

[0018]

[Chemical formula 7](CF3)2CF(CF2)6(CH2)3O
COCH=CH2,

[0019]

[Chemical formula 8] (CF3)2CF(CF2)10(CH2)3OCOC
(CH3)=CH2,

[0020]

[Chemical formula 9] CF3(CF2)4CH(CH3)OCOC(
CH3)=CH2,

[0021]

[Chemical formula 10]

[0022]

[Chemical formula 11] CF3CH2OCH2CH2OCOCH=C
H2,

[0023]

[Chemical formula 12]C2F5(CH2CH2O)2CH2OCO
CH=CH2,

[0024]

[Chemical formula 13](CF3)2CFO(CH2)5OCOCH
=CH2,

[0025]

[Chemical formula 14] CF3(CF2)4OCH2CH2OCOC
(CH3)=CH2,

[0026]

[Chemical formula 15] C2F15CON (C2H5) CH2OCO
C(CH3)=CH2,

[0027]

[Chemical formula 16] C2F5CON (C2H5) CH2OCOC
H=CH2,

[0028]

[Chemical formula 17] CF3(CF2)2CON(CH3)CH(CH3)C
H2OCOCH=CH2,

[0029]

[Chemical formula 18]H(CF2)6C(C2H5)OCOC(C
H3)=CH2,

[0030]

[Chemical formula 19]H(CF2)8CH2OCOCH=CH2,

[0031]

[Chemical formula 20]H(CF2)4CH2OCOCH=CH2,

[0032]

[Chemical formula 21]H(CF2)6CH2OCOC(CH3)=
CH2,

[0033]

[C22]

[0034]

[Chemical formula 23] CF3(CF2)7SO2N(CH3)CH2CH2O
COCH=CH2,

[0035]

[Chemical formula 24] CF3(CF2)7SO2N(CH3)CH2CH2O
COC(CH3)=CH2,

[0036]

[Chemical formula 25] CF3(CF2)7SO2N(CH3)(C
H2) 10OCOCH=CH2,

[0037]

[C26]C2F5SO2N(C2H5)CH2CH2
OCOC(CH3)=CH2,

[0038]

[Chemical formula 27] CF3(CF2)7SO2N(CH3)(C
H2) 4OCOCH=CH2,

[0039]

[C28]C2F5SO2N(C3H7)CH2CH2
OCOC(CH3)=CH2,

[0040]

[C29]C2F5SO2N(C2H5)C(C2H5
)HCH2OCOCH=CH2, Next, the monomer represented by the above chemical formula 2 may be used to constitute the structural unit (A), and is also an essential component to constitute the structural unit (B). . Specifically, the monomer represented by chemical formula 2 is methyl acrylate and/or methyl methacrylate [hereinafter ((
Collectively called methyl meth)acrylate. The same applies below], ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate,
tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, (meth)acrylate Benzyl acid, (meth)acrylic acid-N,N
-(meth)acrylic acid ester such as dimethylaminoethyl, (meth)acrylic acid hydroxylethyl ester,
Hydroxy esters of (meth)acrylic acid such as (meth)acrylic acid hydroxypropyl ester, (meth)acrylic acid-3-chloro-2-hydroxypropyl ester, (meth)acrylic acid triethylene glycol ester, (meth)acrylic acid Polyethylene glycol and polypropylene glycol esters of (meth)acrylic acid such as acid dipropylene glycol ester, aromatic vinyl type monomers such as styrene, vinyltoluene, α-methylstyrene, vinyl formate, vinyl acetate, and vinyl propionate. , carboxylic acid vinyl esters such as vinyl stearate, (meth)acrylamide, N-methylol (
meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-(meth)acryloylmorpholine, 2
Examples include vinyl monomers containing an amide group such as -acrylamide-2-methylpropanesulfonic acid, (meth)acrylic acid, and itaconic acid. One or more of these monomers may be appropriately selected and used.

Next, the structural unit (B) in the block copolymer of the present invention will be explained. The structural unit (B) consists of a polymer portion derived from the above chemical formula 2 and a polymer portion having chemical formula 3 as a unit. This structural unit (B) exhibits compatibility with the epoxy resin and chemical reactivity with curing agents such as amine compounds and acid anhydride compounds, which will be described later, to maintain the bulk properties of the epoxy resin. Furthermore, it is essential for preventing the fluorine-containing groups from falling off on the surface and maintaining the above-mentioned properties attributed to the fluorine-containing groups on the surface for a long period of time.

The proportion of chemical compound 3 in the structural unit (B) is 10
~70% by weight. If it does not reach 10% by weight, the compatibility and chemical reactivity between the block copolymer and the epoxy resin will decrease, and the mechanical strength of the epoxy resin will decrease, especially in cases where the amount of the block copolymer in the composition is high. . Further, the fixation of the fluorine-containing groups on the surface becomes insufficient, and the sustainability of the modification effect decreases. On the other hand, when the amount exceeds 70% by weight, the compatibility between the block copolymer and the epoxy resin becomes good, but on the other hand, the surface orientation of the block copolymer decreases, and the expression of functions based on fluorine-containing groups becomes insufficient. Become.

Furthermore, the structural unit (B) is composed of the above-mentioned chemical formula 2 as an essential component, thereby exhibiting compatibility with the epoxy resin and surface orientation of the block copolymer. Next, the structural unit (
The weight ratio of A) and structural unit (B) is 70/30 to 10/
It is 90. If the proportion of the structural unit (A) exceeds 70% by weight, the compatibility with the epoxy resin and chemical reactivity will decrease, which is undesirable. In addition, the ratio of structural units (A) is 10
When the amount is less than % by weight, the function of fluorine derived from the structural unit (A) cannot be sufficiently expressed on the surface of a film or molded product formed from the epoxy resin.

Next, a method for producing the fluorine-containing block copolymer of the present invention will be explained. As a manufacturing method, from the viewpoint of ease of industrial productivity and versatile performance, polymeric peroxides having two or more peroxy bonds in one molecule, and polymeric peroxides having two or more azo bonds in one molecule are selected. It is preferable to produce by radical polymerization using a polyazo compound as a polymerization initiator. As the polymerization method, ordinary bulk polymerization method, suspension polymerization method, solution polymerization method, emulsion polymerization method, etc. are employed.

The production method using polymeric peroxide as a polymerization initiator will be specifically explained as follows. First, using polymeric peroxide, a copolymerization reaction of the monomer shown by the above chemical formula 2 forming the structural unit (B) and glycidyl (meth)acrylate forming the chemical formula 3 is carried out, and a peroxy bond is introduced into the chain. A peroxy bond-containing vinyl polymer is obtained. When polymerization is carried out by adding the monomer shown by the above chemical formula 1 or the mixture of the monomer shown by the chemical formula 1 and the monomer shown by the above chemical formula 2 forming the structural unit (A), peroxy The bonds are cleaved at the peroxy bonds they contain, and a block copolymer can be efficiently obtained.

The polymeric peroxide mentioned above may be any compound having two or more peroxy bonds in one molecule.
Those described in No. 54239, JP-A No. 60-22410, etc. can be preferably used. Compositional analysis of the block copolymer of the present invention can be performed by known means such as NMR analysis, IR analysis, and elemental analysis.

[0047] Water resistance, which is the object of the present invention,
Properties such as moisture resistance, stain resistance, and mold releasability depend on the composition at a certain depth of the surface of an object formed from the epoxy resin composition of the present invention. Examples of this object include molded products having a predetermined shape by casting an epoxy resin composition, and coating films obtained by coating on various substrates. An X-ray photoelectron analyzer (
(hereinafter abbreviated as ESCA) is known. When measuring using this device under the condition that the escape angle of photoelectrons from the object surface is 90 degrees, the molar ratio of fluorine atoms to carbon atoms (hereinafter referred to as [F
]/[C]) is required to be 0.4 to 2.5, and preferably 0.7 to 2.5.

[0048] If [F]/[C] is less than 0.4, properties such as water resistance, moisture resistance, stain resistance, and mold releasability will be insufficient. The higher [F]/[C] is, the better it is, but in the epoxy resin composition of the present invention, the compositionally upper limit is 2.5, and there is virtually no composition higher than this. [F]/[C] on the surface of an object formed from the epoxy resin composition of the present invention is determined by the amount and structure of the fluorine-containing block copolymer in the composition of the present invention. The structure is as described above. [F]/[C] is 0.4 to 2 without impairing the bulk properties of the epoxy resin.
．． 5, it is necessary that the amount of the fluorine-containing block copolymer be 0.1 to 40 parts by weight based on 100 parts by weight of the epoxy resin. If it is less than 0.1 part by weight [F
]/[C] is difficult to set to 0.4 or more. Moreover, if it exceeds 40 parts by weight, the mechanical strength of the epoxy resin decreases.

In the present invention, the compatibility and chemical reactivity of the epoxy resin and the fluorine-containing block copolymer are good, and the composition of the surface of the object formed from the epoxy resin composition is within a specific range. The purpose is achieved by To this end, it is necessary that the amount of the fluorine-containing block copolymer be 0.1 to 40 parts by weight per 100 parts by weight of the epoxy resin, and that the object formed from the epoxy resin composition be measured using the above-mentioned specific measuring method. Measured [F]/[C]
is required to be 0.4 to 2.5. In addition, since the structure and composition of the block copolymer can be adjusted as appropriate,
There are no particular restrictions on the type and performance of the epoxy resin itself as long as it has performance suitable for each use.

Examples of the epoxy resin include bisphenol A epoxy resins having glycidyl groups at both ends and having various molecular weights, bisphenol F epoxy resins,
A phenol-novolac type multifunctional epoxy resin having glycidyl groups at the terminal and side chains, an orthocresol novolac type epoxy resin, a brominated epoxy resin, a glycidyl ester type epoxy resin, a biphenyl type epoxy resin, etc. are used. Furthermore, the epoxy resin may be in any of liquid, solid, solvent-soluble, and emulsion types.

The epoxy resin composition of the present invention may contain various organic solvents and reactive diluents such as glycidyl ether. In addition, curing agents are usually used, such as amine compounds such as aliphatic polyamines, polyaminoamides, aromatic diamines, alicyclic diamines, imidazole, and tertiary amines, acid anhydride compounds, phenolic resins, amino resins, and mercaptan compounds. compounds, dicyandiamide, Lewis acid complex compounds, etc. are used. These curing agents can be incorporated into the composition of the present invention and used as a one-component type, or can be used as a two-component type that is mixed at the time of use. By creating a cured epoxy resin using these curing agents, chemical bonding between the epoxy resin and the fluorine-containing block copolymer can be achieved.

The epoxy resin composition of the present invention can be used in inks and coating materials for electronic components, various electrical insulating materials such as sealants for semiconductor devices, and various heavy duty anticorrosion paints.

[0053]

[Examples] Examples embodying the present invention will be explained below in comparison with comparative examples. In each Example, Comparative Example, and Production Example, parts represent parts by weight, and % represents weight %. (Production Example 1) (1) Synthesis of peroxy bond-containing polymer 150 parts of methyl ethyl ketone (hereinafter referred to as MEK) was charged into a reactor equipped with a thermometer, a stirrer, and a reflux condenser, and heated to 70°C while blowing nitrogen gas. 135 parts of KEK, 120 parts of methyl methacrylate (hereinafter referred to as MMA), 80 parts of glycidyl methacrylate (hereinafter referred to as GMA),

[0054]

[Chemical formula 30]-(CO(CH2)4COO(C2H4O)
A mixed solution consisting of 10-12 parts of 3CO(CH2)4COOO) was charged over 2 hours, and a polymer reaction was further carried out for 4.5 hours to obtain a peroxy bond-containing polymer. MMA
, the polymerization conversion rate of GMA is shown in the gas chromatogram (hereinafter referred to as G
The results of measuring the amount of residual monomer (referred to as C) were 97% or more in all cases.

This polymer solution was diluted to 4 times its volume with acetone, and then poured into a large excess of hexane with stirring to re-precipitate the polymer. The precipitated polymer was sufficiently dried to obtain a powdery polymer. As a result of GC analysis, it was confirmed that no monomer remained. The amount of active oxygen in this powdered polymer was 0.11%, and the number average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC) was 14,500. (2) Synthesis of block copolymer Powdered polymer obtained in (1) above
28 parts

[0056]

[Chemical formula 31] CF3(CF2)7CH2CH2OCOCH
=CH212 MEK
60 parts of the mixed solution was charged into a reactor equipped with a thermometer, a stirrer, and a reflux condenser, and a polymerization reaction was carried out at 70° C. for 10 hours while blowing nitrogen gas. The polymerization conversion rate of the fluorine monomer was 98%.

The resulting polymer solution was diluted to 4 times its volume with Ascent and poured into a large excess of water with stirring to re-precipitate the polymer. The precipitated polymer was sufficiently dried to obtain a powdery polymer. 30 parts of this fine powder was added to a mixed solvent consisting of 450 parts of methanol and 150 parts of ethyl acetate.
The mixture was stirred at ℃ for 8 hours to extract one of the by-produced components, an acrylic polymer that does not contain fluorine. Next, the remaining polymer was poured into 60 parts of trichlorotrifluoroethane and stirred at 40° C. for 48 hours to extract the fluoropolymer.

As a result, it was found that the above powder was composed of block copolymer/fluorine-free acrylic polymer/fluorine-containing polymer in a composition ratio of 7.5/2.1/0.4. Understood. Therefore, the weight ratio of the fluorine-containing polymer part [structural unit (A)] and the fluorine-free polymer part [structural unit (B)] in the block copolymer is 3.
It turned out to be 3/67. Further, as a result of NMR analysis of the block copolymer using deuterium-substituted acetone, it was found that the constituent components of the fluorine-free polymer portion had an MMA/GMA ratio of 60/40 as originally prepared. (Production Examples 2 to 6) Using the same reactor as used in Production Example 1, 150 parts of MEK was charged into the reactor, and 7 parts of MEK was charged while blowing nitrogen gas.
It was heated to 0° C., and the mixed solution shown in Table 1 was charged over 2 hours, and the polymerization reaction was further carried out for 4.5 hours to obtain a peroxy bond-containing polymer. As a result of measuring the amount of residual monomer by GC, the polymerization conversion rate was 98% or more in all cases.

[0059] Subsequently, with 160 copies of MEK

0060
]

[Chemical formula 32] CH2=CHCOOC2H4N(CH3)S
A mixed solution with 86 parts of O2C8F17 was added dropwise over 30 minutes, and a polymerization reaction was further carried out at 70°C for 3 hours and at 77°C for 3 hours. As a result of GC analysis, the polymerization conversion rate of monomer was 9.
It was 8% or more.

[0061]

[Table 1]

(Production Examples 7 to 10) The peroxy bond-containing polymer powder synthesized in (1) of Production Example 1 and various monomers,
After adjusting the mixed solution consisting of organic solvent as shown in Table 2, Table 2
A block copolymer was obtained by performing synthesis under the polymerization conditions shown in . The polymerization results are also shown in Table 2.

[0063]

[Table 2]

(Production Examples 11 and 12) 100 parts of MEK was charged into the reactor used in Production Example 1, and heated to 85° C. while blowing nitrogen gas. The mixed solution shown in Table 3 was added to it over 2 hours, and the polymerization reaction was further carried out for 9 hours.
A random copolymer was obtained. The polymerization results are shown in Table 3. In addition, as a polymerization initiator,

[0065]

[Chemical 33]CH3(CH2)3CH(C2H5)COO
Ot-Bu was used.

[0066]

[Table 3]

(Examples 1 to 5, Comparative Examples 1 to 9) Production Example 1
A molded body was prepared using the composition consisting of the fluorine-containing block copolymer obtained in steps 1 to 12 and an epoxy resin, and various properties of this molded body were evaluated. All of the fluorine-containing copolymers synthesized in Production Examples 1 to 12 were adjusted by adding MEK so that the solid content concentration was 20% by weight.

100 parts of bisphenol A epoxy resin (trade name Epicote 828, manufactured by Yuka Shell Epoxy Co., Ltd.);
30 parts of bis(para-aminocyclohexyl)methane, ME
An epoxy resin composition was prepared by adding a predetermined amount of the above fluoropolymer solution to a polymer solution consisting of 130 parts of K. Next, the composition was poured into an aluminum container with a flat bottom and heated at 80°C for 20 minutes with the surface exposed to air.
The solvent was removed by fractional treatment, and further heat curing was performed at 120° C. for 40 minutes to create a molded product with a thickness of 2 mm.

The following tests were conducted on this molded article. ■Surface composition: Using a Shimadzu ESCA850 photoelectron spectrometer, MgKα as the X-ray source, voltage 8KV,
[F]/[C] was measured under the conditions of a current of 30 mA, an analysis chamber of 6 x 10-6 Pa, and a photoelectron escape angle of 90 degrees. ■Bulk properties: The molded body was heated to 20°C using IPA/MEK (8
The degree of transparency and brittleness of the object was evaluated before and after immersion for 24 hours in 0/20 weight ratio).

◎: Shows good transparency before immersion. There is no decrease in transparency even after immersion, and the shape of the molded product is completely maintained. Good: Transparency before immersion is slightly lower than when no fluoropolymer is added, but there is no change in transparency due to immersion. Moreover, the shape of the molded body is completely maintained.

Δ: A decrease in transparency is observed before immersion, and this tendency increases after immersion. Crazing (cracks) can be seen in the molded product due to immersion. ×: The molded article before immersion is whiteish. The shape is destroyed after immersion. (2) Water resistance: The molded body was immersed in hot water at 90°C for 100 hours to evaluate the degree of transparency and brittleness of the body.

◎: There is no change in the transparency and shape of the molded product. ○: The transparency of the molded product slightly decreases, but there is no change in shape. △: The transparency of the molded article is decreased, and swelling due to hot water is observed. ×: The molded product is white, swells, and its shape is partially destroyed. ■Stain resistance: After marking with a red marker manufactured by Pentel, the surface was left for 24 hours, the surface was rubbed with a towel soaked in water, and judgment was made based on the degree of removal of the marker.

○: Magic is completely removed. △: Slight traces remain. ×: Almost no magic can be removed. ■ Release property Sekisui Chemical's adhesive tape with a width of 5 cm was rolled back and forth 5 times with a rubber roller weighing 2 kg, and left to stand for 2 hours after being thickly applied.
The 180 degree peel force was measured at a peel rate of mm/min.

The evaluation results are shown in Tables 4 and 5.

[0075]

[Table 4]

[0076]

[Table 5]

[0077] From these results, it was found that the molded article formed from the epoxy resin composition of the present invention has a high concentration of fluorine-containing groups on its surface while maintaining its bulk properties.
It is clear that excellent stain resistance, mold releasability, and water resistance are provided. On the other hand, as shown in the comparative examples, in epoxy resin compositions containing a fluoropolymer in a composition or amount outside the scope of the present invention, the bulk properties may deteriorate or the amount of fluorine-containing groups present on the surface may decrease. It was found that stain resistance, mold releasability, and water resistance were low.

[0078]

According to the first invention, compatibility and chemical reactivity between the fluorine-containing block copolymer and the epoxy resin can be achieved, and the fluorine-containing block is formed on the surface of an object formed from the epoxy resin composition. Two functions are simultaneously expressed: the copolymer is efficiently oriented and fluorine-containing groups are present at a high concentration on the surface. As a result, the epoxy resin has the excellent effect of imparting water resistance and moisture resistance based on the fluorine-containing group, as well as surface properties such as stain resistance and mold releasability, without impairing the inherent properties of the epoxy resin.

Further, according to the second invention, the same effect as the first invention can be achieved by setting the structural unit (A) and structural unit (B) constituting the block copolymer at a predetermined ratio. This has the effect that it is effectively demonstrated.

Claims (2)

[Claims] Claim 1: An epoxy resin composition containing an epoxy resin and the following fluorine-containing block copolymer,
The content of the fluorine-containing block copolymer is 0.1 to 40 parts by weight based on 100 parts by weight of the epoxy resin, and the escape angle of photoelectrons from the surface of the object formed from the epoxy resin composition is An epoxy resin composition characterized in that the molar ratio of fluorine atoms to carbon atoms is 0.4 to 2.5 as measured by an X-ray photoelectron analyzer at 90 degrees. Fluorine-containing block copolymer: a structural unit (A) derived from the following chemical formula 1, and a structural unit (B) consisting of a polymer portion derived from the following chemical compound 2 and a polymer portion having the following chemical compound 3 as a unit. The proportion of the polymer portion having chemical formula 3 as a unit in the structural unit (B) is 10 to 70% by weight, and the ratio of structural unit (A)/structural unit (B) is 70/30 to 70% by weight. A fluorine-containing block copolymer with a ratio of 10/90. [Chemical formula 1] [Chemical formula 2] [Chemical formula 3] 2. The fluorine-containing block copolymer comprises a structural unit (A) consisting of 40% by weight or more of a polymer portion derived from the chemical formula 1 and 60% by weight or less of a polymer portion derived from the chemical formula 2; , consisting of a structural unit (B) consisting of a polymer part derived from the above chemical formula 2 and a polymer part having the above chemical formula 3 as a unit, and the proportion of the polymer part having the chemical formula 3 as a unit in the structural unit (B) is 10 to 70% by weight, and the ratio of structural unit (A)/structural unit (B) is 70/3 by weight.
The epoxy resin composition according to claim 1, wherein the epoxy resin composition has a molecular weight of 0 to 10/90.