KR20130047280A - Manufacturing method of new nvolac resin - Google Patents

Abstract

PURPOSE: A manufacturing method of a phenol novolac type resin is provided to obtain divalent or less functional phenols with high purity by using a molar ratio of a phenol/formaldehyde with a specific range, thereby obtaining a commercially usable phenol novolac resin without special treatment. CONSTITUTION: A manufacturing method of a phenol novolac type resin comprises a step of putting phenol, formaldehyde, and acid catalyst into a reactor; a step of stirring and mixing the material and obtaining the phenol novolac type resin by removing water, unreacted water, and residual catalyst from the result. The reaction molar ratio of the phenol and aldehyde is 3-6 moles and desirably 4-5 moles. The acid catalyst is hydrochloric acid, sulfuric acid, salicylic acid, p-toluenesulfonic acid, and organic or inorganic oxalic acid.

Description

Novel manufacturing method of phenol novolak-type resin, epoxy resin manufacturing method using the same and flame retardant epoxy resin manufacturing method using the same {Manufacturing method of new nvolac resin}

The present invention relates to a process for producing a novel novolak-type phenol resin, a method for producing an epoxy resin using the same, a method for producing a new phosphorus-containing flame retardant epoxy resin using the epoxy, a prepreg and a copper foil using the flame-retardant epoxy resin. It relates to a method for producing a laminate.

The phenol novolak resin in the widely used novolak phenol resin is obtained by the condensation reaction of phenol and foraldehyde with acid catalyst. Typically, the molar ratio of phenol and formaldehyde is in the range of about 1 to 3 moles, and on average contains 4 to 5 phenolic compounds per molecule, and the phenolic content of divalent or less is 10 to 30% by weight. Doing.

It is known that the distribution of phenols per molecule of the novolak-type phenol resin is determined by the molar ratio (hereinafter, P / F molar ratio) between phenols and aldehydes. For example, polyhydric phenol, which is a raw material of the most widely used phenol novolac epoxy resin obtained by reacting with a P / F molar ratio of 2.05, has a phenolic content of less than 25% and a 20% content of trivalent phenolic content. In addition, the content of tetravalent phenol is more than 15%.

Increasing the P / F molar ratio increases the content of the dihydric phenol, resulting in a lower molecular weight of the final product. The closer the P / F molar ratio is to 1, the lower the dihydric phenol is and the higher the content of the tetravalent phenol. The molecular weight of the phenol novolak resin, which is the final product, increases.

When the content of the dihydric phenol is increased in the novolak-type phenolic resin, the effect of lowering the overall molecular weight is lowered, and the viscosity is lowered. Is low, making it difficult to obtain the desired properties.

On the other hand, in order to prepare a novolak-type phenolic resin having a low content of dihydric phenol, if the P / F molar ratio is low, the viscosity is high and the molecular weight is high. The reaction does not occur smoothly, and a large amount of by-products are generated, making it difficult to prepare an epoxy resin.

As such, the method of lowering the phenolic content of divalent or less by the conventional method must lower the P / F molar ratio, which inevitably generates a high molecular weight polyhydric phenol, which causes many problems in the epoxidation reaction.

A method for producing a phenol novolak resin having a low content of phenolic compounds having a dihydric acid or less, as described in Japanese Patent Office No. 62-501780, a method of extracting a phenolic compound having a dihydric acid or less using hot water after the reaction, As described in Japanese Patent Application Laid-Open No. 90-60915, a slightly soluble solvent is added to water, followed by adding a water-soluble alcohol and water to remove the low-cost phenol, or as described in Japanese Patent Application Laid-Open No. 6-128183. After preparing bisphenol F and obtaining high purity bisphenol F through thin film distillation, a method of obtaining a phenol novolak resin by reacting phenol and aldehyde again with the remaining low molecular weight polyhydric phenol is described.

However, these methods are not only complicated in process, but also have a limitation in commercial use due to the removal of dihydric phenol or lower phenols, and are very effective in producing high-purity bisphenol F by the method of Japanese Patent Application Laid-Open No. 6-128183. However, for the commercially available phenol novolac co-occurrence disclosed in the patent there is a problem of producing the reaction by reacting again. In addition, only the opinion of producing a high molecular weight phenol novolak resin by reacting again with a commercial method using a new phenol novolak resin, which is a leach product, was disclosed.

The present invention closely examines the above problems, and as a result, after preparing a general phenol novolak resin using a specific range P / F molar ratio, if a portion of the divalent or less phenol is separated, high purity 2 It has been found that not only the following phenols can be obtained, but also commercially available phenol novolak resins can be obtained without special treatment.

In addition, the phenol novolak resin obtained by the above method has a molecular weight, softening point, and epoxy similar to that of the phenol novolak resin commonly used as a raw material for producing an epoxy resin, although the content of dihydric phenol is lower than 10%. The reactions have similar reactivity and process effectiveness.

In addition, when the epoxy resin is produced using the phenol novolak resin obtained by the above method, it is possible to obtain a new epoxy resin having a very high heat resistance, an epoxy group functional group, etc., while the conventional properties of the epoxy resin can be obtained very similarly.

In addition, when the phosphorus-containing flame-retardant epoxy resin is prepared by reacting with a reactive phosphorus compound using the epoxy resin obtained by the above method, the heat resistance is higher than that of the phosphorus-containing flame-retardant epoxy resin obtained from commercially available similar molecular weight novolak epoxy resins. It was found to be greatly improved.

In order to solve the above problems, the present inventors closely examined the molecular structure of an epoxy resin derived from a novolak-type phenolic resin, and as a result, if the dihydric phenols are controlled below a certain component, heat resistance, hygroscopicity, reactivity, as well as copper foil laminate It has also been found that resin flow problems that can occur in fabrication and PCB processes can be significantly improved.

Since the reaction is equipped with a general chemical reaction device such as a stirrer, a temperature control device, a reflux device equipped with a cooler, an electric device, and a pressure reduction device, phenol, formaldehyde, and an acid catalyst are added thereto, and the reaction is performed at a constant temperature for a certain time under stirring. The produced product, unreacted phenol and residual catalyst are removed from the reaction product to obtain a phenol novolak resin.

As the phenol used in the present invention, phenol derivatives capable of producing a novolak resin by reacting with aldehydes such as phenols substituted with methyl groups, such as o-cresol, m-cresol, and p-cresol, in addition to phenol, can be used without limitation.

Moreover, the reaction molar ratio P / F molar ratio of a phenol and an aldehyde is 3 or more normally, Preferably it is 3-6 mol, More preferably, it is 4-5 mol. When the P / F molar ratio is 3 mol or less, the high purity bisphenol F outflow called n = 0 decreases, the molecular weight of the desired new phenol novolak resin becomes high, and when the molar ratio is 6 mol or more, it is not commercially preferable. The production of high purity bisphenol F and commercially preferred novel phenol novolak resin at a molar ratio of 4.5 moles of P / F can be obtained 1: 1 by weight, which is considered to be the most preferable molar ratio. By controlling the amount to 6 moles, the production of high-purity bisphenol F and novel phenol novolak resins can be controlled.

The acid catalyst used may be a solid acid catalyst fixed bed such as a cation exchange resin, or may be hydrochloric acid, sulfuric acid, salicylic acid, p-toluene sulfonic acid and oxal organic acid and inorganic acid.

The reaction temperature and time usually follow the reaction temperature for producing a phenol novolak resin. Usually, when manufacturing a phenol novolak resin, reaction temperature is 50-110 degreeC and time is 0.5 to 10 hours.

The catalyst removal process varies depending on the type of catalyst, but in the case of commonly used oxal organic acid (hydroxyl), both the effluent and the phenol removal process are simultaneously removed.

Subsequently, unreacted phenol and effluent are removed by distillation under reduced pressure to obtain a phenol novolak resin. In general, it is preferable to minimize the content of unreacted phenol through the process of separating the phenol and water during the distillation under reduced pressure, and the step of steaming steam into the reactor droplets in the final decompression step.

The phenol novolac resin thus prepared was continuously supplied to a thin film evaporator equipped with a cooling device, and the distillation temperature was 250 ° C or higher and 300 ° C at a pressure of 10torr or lower, preferably 5torr or lower, more preferably 3-5torr or lower. Below, preferably 260 ° C or more and 290 ° C or less, the rate of supplying the phenol novolak resin to the still is 50 kg / hr or more, preferably 80 kg / hr or more, more preferably 100 kg / hr or more and 300 kg / hr or less Is carried out. The number of distillers does not have to be several.

Japanese Patent Laid-Open No. 6-128183, which discloses a process similar to the present invention, discloses that when a preferable distillation temperature is performed at 250 ° C. or higher, there is a risk of coloration and pyrolysis of effluents and effluents. It was found that if the resin was injected into the still, and the distillation was not performed several times and the distillation was performed at a high temperature, at least 270 ° C. or more, only one distillation was performed, and the productivity was improved without fear of color change and pyrolysis of the product.

By the above method, high-purity bisphenol F obtained by distillation through a thin film and new phenol novolak resin remaining in the still without distillation can be obtained.

When the process is carried out in the P / F molar ratio of the above-described range

1) Since the amount of phenol expected to remain unreacted during the reaction is less than the case of 6 mol or more, the productivity per unit batch is higher than the method disclosed in the literature, the productivity is excellent,

2) Since the amount of high-purity bisphenol F and new phenol novolac obtained by distillation is similar, it is advantageous to control the production according to the situation.

3) Since the general properties of the novel phenol novolac obtained during distillation are similar to general purpose phenol novolac for epoxy resin production, it is commercially useful because it can be used for the preparation of epoxy resin without any special operation.

Another aspect of the present invention is to prepare an epoxy resin using a novel phenol novolak resin obtained by the above method as a raw material.

The novel phenol novolac resin obtained by the above method does not show a big difference in appearance characteristics and reactivity with phenol novolac commonly used in reaction with epichlorohydrin (ECH), which is generally used as a main raw material for epoxy reactions. Even if the epoxy resin is prepared directly without changing the process, it does not show a big difference in processability, etc., while most of the general characteristics are similar, there is an advantage that the heat resistance is greatly improved.

The novel phenol novolac resin obtainable by the method of the present invention has a relatively high end group content compared to commercial phenol novolac resins having a low molecular weight and a high content of trivalent or higher phenolic compounds, having a similar range of molecular weight. . This is maintained even when the epoxy resin is prepared by epoxidation. The phenol content of the phenol novolak resin and the epoxy group content of the epoxy resin after epoxidation are proportional to each other. Therefore, the epoxy resin epoxidized using the novel phenol novolak resin produced by the method of the present invention also has a low divalent epoxy content and a high trivalent or higher epoxy content. Therefore, the properties of the epoxy resin itself, such as equivalent weight, viscosity, molecular weight, are similar to the general phenol novolac epoxy resin, and the properties such as heat resistance are greatly improved by increasing the crosslinking density due to the content of many epoxy bodies.

In another aspect of the present invention, a novel phosphorus-containing flame-retardant epoxy resin is obtained by using a novel phenol novolac epoxy resin obtained by the above method as a base resin.

DOPO (9,10-dihydr-9-oxy-10-phosphaphenanthrene-10oxide), which is widely used in the production of phosphorus-containing flame-retardant epoxy resins, has only one active hydrogen at the end of the phosphorus group, so Reaction with 1 equivalent of epoxy groups reduces the total epoxy groups by that amount. Reducing the epoxy group means that the crosslinking density decreases after the final crosslinking reaction, and when the crosslinking density decreases, thermal characteristics, physical properties, and the like tend to generally fall. Especially. Epoxy crosslinking density has a great influence on environmental properties such as heat resistance and moisture absorption, such as Tg.

Epoxy resins obtained from novel phenol novolac resins have a higher epoxy group content than conventional phenol novolac epoxy resins, so that less end group reduction occurs from a single reactor raw material such as DOPO. From this point, a higher crosslinking density can be obtained, and more improved heat resistance such as Tg can be expressed.

Among the molecular structures constituting the novolak-type phenolic resins, epoxy resins derived from novolak phenolic resins having a content of at least trivalent or higher phenolic compounds and a bivalent or lower phenolic compound controlled to a certain component or less are used. The flame-retardant epoxy resin obtained by reacting with the reactive phosphorus compound has only general properties such as heat resistance, withstand voltage, and hygroscopicity than those using an epoxy resin originating from a novolak phenol resin having no controlled dihydric phenol content. In addition, stable reactivity, processability at the time of manufacturing a copper foil laminated board, etc. are remarkably improved.

1 is a GPC pattern of a novel phenol novolak resin obtained in Example 1. FIG.
2 is a GPC pattern of a phenol novolac epoxy resin obtained in Example 2. FIG.
3 is a GPC pattern of a phenol novolak resin for general epoxy of Comparative Example 2. FIG.
4 is a GPC pattern of a phenol novolac epoxy resin obtained from Comparative Example 2. FIG.

The present invention relates to a method for adjusting the phenolic content of divalent or less in the composition of the novolak phenolic resin, a method for producing an epoxy resin from a novolak phenolic resin having a divalent or less phenolic compound and a compound containing the epoxy resin and Reacts to a new flame retardant epoxy resin.

Hereinafter, the method for implementing the present invention will be described in more detail.

Example 1

Into a four-necked flask equipped with a stirrer, a nitrogen inlet, and a reflux tube connected to a cooling tube, 1300 g of phenol, 144 g of PW, and 3.9 g of oxalic acid were added and dissolved at 80 ° C. 249 g of 37% aqueous formalin solution was metered into the system for 30 minutes, and the reaction mixture was heated at 90 ° C. for 3 hours. At this time, the P / F molar ratio is 4.5 mol. The temperature of the system was sequentially raised to 112 ° C., followed by a dehydration step, and then the temperature was reduced under reduced pressure to recover unreacted phenol while preventing droplets of the system from 180 ° C. to 5 torr. When no more effluent comes out of the system, steam is injected into the system under reduced pressure to proceed with the stipping process to remove even the remaining amount of phenol to obtain 511 g of a phenol novolak resin.

The prepared phenol novolac resin is quantitatively supplied to the thin film evaporator at a rate of 100 kg / hr using a liquid feeding pump. The fruit temperature of the thin film evaporator is set to 285 ° C. and the degree of vacuum is set to 3 torr. The evaporated portion through the thin film was obtained through recrystallization to give 251g high purity bisphenol F having 98% of dihydric phenol, and the 260g new phenol novolac having 10% of divalent phenol. Obtained as resin. The molecular weight of the novel phenol novolak resin was Mn = 500 g / mol, Mw = 565 g / mol and Mn / Mw = 1.1292. 1 shows a GPC pattern of a phenol novolak resin. The area corresponding to 37.325 minutes of retention time was a dihydric phenol, and its content was 9.85%.

[Example 2]

260 g of the novel phenol novolak resin of Example 1 and 1030 g of epichlorohydrin (ECH) were added to a 3-liter four-necked flask equipped with a decanter, a cooling tube, a stirrer, and a nitrogen inlet, and dissolved by heating to 60 ° C. When the solution in the system is completely dissolved, 16 g of 50% aqueous solution of caustic soda is metered in for 1 hour, followed by preliminary reaction for 3 hours. Thereafter, a reduced pressure of 65 ° C. and 150 torr was added to the system, and 194 g of an aqueous 50% caustic soda solution was metered in for 4 hours to proceed with the present reaction. Water generated during the reaction is continuously removed from the system through a decanter. After completion of the reaction, the reaction mixture was gradually heated and reduced in pressure to 150 to 5torr to remove unreacted ECH. After the completion of the ECH outflow, the mixture was decompressed to 110 ° C., 400 g of methyl isobutyl ketone was added to dissolve, and the purification reaction was carried out. After neutralization reaction and washing with water twice, methyl isobutyl ketone is removed under reduced pressure to obtain a new phenol novolac epoxy resin.

In this case, the epoxy equivalent was 179 g / eq, the hydrolyzed chlorine content was 50 ppm, the viscosity was I, and the yield was 98% relative to the theoretical resin amount. There was no significant difference from the commonly used phenol novolac epoxy resin. Table 1 shows the general characteristics of the conventional phenol novolac epoxy resin and the epoxy resin prepared by the above method. The molecular weight distribution (GPC) of the epoxy resin is shown in FIG.

[Example 3]

Into a 2-liter four-necked flask equipped with a reflux tube, a stirrer, and a nitrogen inlet, 300 g of the novel phenol novolac epoxy resin obtained in Example 2 and 79.64 g of HCA were added and dissolved at 110 ° C. at elevated temperature. 0.16 g of triphenyl phosphine (TPP) was added to the completely dissolved system, and the reaction was performed at 160 ° C for 3 hours. After completion of the reaction, 170 g of acetone is gradually added to the system to dissolve, thereby obtaining a phosphorus-containing flame-retardant epoxy resin. At this time, the theoretical phosphorus content was 3%, the epoxy equivalent was 298 g / eq, the viscosity of the solution was 290 cps @ 25 ° C, and the nonvolatile content was 70.5%. Table 3 compares the general properties and the curing properties of the epoxy resins.

Comparative Example 1

2000 g of phenol, 86.3 g of formalin and 5.6 g of oxalic acid dihydrate were charged to a 3 L four-necked flask equipped with a stirrer, a nitrogen inlet, a reflux tube connected to a cooling tube. At this time, the P / F molar ratio is 20 mol. It heated to 70 degreeC, stirring, and operated the reflux condenser, and reaction was performed at atmospheric pressure for 4 hours.

Next, the obtained reaction product was heated to 160 ° C. under atmospheric pressure to remove water and a small amount of phenol, and heated to a die pressure of 20 tor and a temperature of 170 ° C. to separate unreacted phenol, and a pressure of 6 tor and a temperature of 210 ° C. It heated up to remove unreacted phenol, and obtained the bisphenol F. The obtained bisphenol F was 200 g and the content of dihydric phenols was 87%.

Next, as a Demister (trade name), the bisphenol F was distilled off using the apparatus which attached the McMahon packing of diameter 15mm and height 20mm. Distillation was carried out at a pressure of 3 mmHg until the final temperature of 250 ° C. to obtain 270 g of high-purity bisphenol F and 79 g of a phenol novolak resin having a divalent phenol content of 7%.

This process was very useful for commercially obtaining high-purity bisphenol F, but the yield of new phenol novolac resins with low dihydric phenol content was very low compared to the complex process, which was remarkably disadvantageous in terms of productivity. The molecular weight of the new phenol novolac was too small to produce a commercially available epoxy resin.

Comparative Example 2

260 g of KPN-2065 (general phenol novolak resin for epoxy at a softening point of 65 ° C) and epichlorohydrin (ECH) in a 3-liter four-necked flask equipped with a decanter, a cooling tube, a stirrer and a nitrogen inlet. 1030g is added and dissolved while heating up to 60 ° C. Thereafter, the process proceeds in the same manner as in Example 2.

At this time, the epoxy equivalent was 179.5 g / eq, the hydrolyzed chlorine was 52 ppm, the viscosity was I +, and the yield was 96.5% compared to the theoretical resin amount. As a result of the epoxy resin production, similar levels were obtained to most of the epoxy physical properties except for the dihydric phenol content compared to Example 2.

The GPC pattern of the phenol novolak epoxy resin (KPN-2065) for general epoxy (FIG. 3) and the phenol novolak epoxy resin obtained from it are shown in FIG.

[Comparative Example 3]

KPN-111 (Gangnam Chemical Co., Ltd., general phenol novolak resin for curing agent at softening point of 105 ° C, dihydric phenolic substance, 9.87%, Mn =) 260 g of 687 g / mol, Mw = 2360 g / mol) and 1030 g of epichlorohydrin (ECH) were added, and dissolved at a temperature of 60 ° C. Thereafter, the process proceeds in the same manner as in Example 2.

At this time, the epoxy equivalent was 189.5 g / eq, the hydrolyzed chlorine content was 150 ppm, the softening point was 64 degreeC, and the theoretical resin yield ratio was 56%. Epoxy resin production was possible, but the yield was very low due to the problem that a large amount of by-products, which are referred to as intermediates, were produced after the main reaction and the purification reaction due to the high molecular weight of the raw material.

[Comparative Example 4]

Into a 2-liter four-necked flask equipped with a reflux tube, agitator, and nitrogen inlet, 300 g of YDPN-638 (manufactured by Kukdo Chemical Co., Ltd., general purpose phenol novolac epoxy resin) epoxy resin and 79.64 g of HCA were added. Proceed in the same manner as 3 to obtain a phosphorus-containing flame-retardant epoxy resin. The theoretical phosphorus content was 3%, epoxy equivalent weight was 299g / eq, solution viscosity was 350cps @ 25 ° C, and the nonvolatile content was 70.4%.

Example 4 and Comparative Example 5

The phosphorus-containing epoxy resin varnish solution was prepared by stirring and dissolving 500 g of phosphorus-containing epoxy resin obtained in Example 3 and Comparative Example 4, 5.1 g of dicyanide diamide, 0.34 g of 2-methyl imidazole, and 100 g of 2-methoxyethanol for 3 hours. Manufacture. 170 ° C. gelation time of each prepared varnish solution is shown in Table 4.

The prepared varnish solution was impregnated into woven glass fibers and dried in an oven at 170 ° C. for 4 minutes to prepare an epoxy-glass fiber prepreg. The gelation time of the semiprecured semipreg and the minimum viscosity upon cure flow are shown in Table 3.

Example 5 and Comparative Example 6

Eight prepregs and 1 oz copper foil prepared from Example 4 and Comparative Example 5 were pressed at 180 ° C. and 300 psi for 90 minutes to prepare a copper clad laminate. PressFlow amount and Tg and Td values of the copper clad laminate were shown in Table 4.

Epoxy Resin Properties Obtained from Example 2, Comparative Examples 2 and 3 Item Epoxy of Example 2 Epoxy of Comparative Example 2 Epoxy of Comparative Example 3 Epoxy equivalent weight
(g / eq) 179 179.5 189.5 Hy-Cl
(ppm) 50 52 150 Viscosity
(Gardener) I I + - Softening point
(℃) - - 65 yield
(% Of theory) 98 96.5 56 Fairness Good Good Bad 2
Epoxy content (area%) 9.03 22.5 8.23

Curing Properties of Epoxy Resin Obtained from Example 2 and Comparative Example 2 Item Example 2 Comparative Example 2 Tear strength (MPa) 6.2 6.1 Flexural Strength (MPa) 117 120 Tensile Strength (MPa) 76 78 Compressive strength (MPa) 270 258 Shore-d 86 84 Tg 126.7 117.8

※ Curing Agent: D-230 (Jeffamine)

※ compounding ratio: Subject: Hardener = 100: 34

※ Curing condition: 80 ℃ × 3hr precure, 100 ℃ × 1hr postcure

※ How to measure

   Tear strength:

   Flexural Strength: ISO-527

   Tensile Strength: ISO-178

   Compressive Strength: ISO-604

   Shore-D: ISO-868

Tg: using Mettler DSC 823, 20 ~ 200 ℃ heating rate 20 ℃ / min

Comparison of the properties of flame retardant epoxy resins obtained from Example 3 and Comparative Example 4 Item Example 3 Comparative Example 4 equivalent weight
(g / eq) 298 290 Chlorine
(ppm) 33 32 Nonvolatile matter
(%) 70.5 70.4 Viscosity
(cps @ 25 ℃) 290 299 Phosphorus content
(%) 3 3

 Comparison of physical properties obtained from Examples 4 and 5 and Comparative Examples 4 and 5 Item Example 4,5 Comparative Example 4, 5 Varnish Gel Time
(sec, 170 ℃) 260 255 Prepreg Gel Time
(sec, 170 ℃) 132 134 Minimum viscosity during hardening flow
(cps) 6000 5200 Impregnation Good Good Copper Clad Laminate Characteristics Resin Flow
(%) Less than 1% 2% Tg
(℃) 151 133 Td
(℃) 362 352

※ Method of measurement: IPC-TM-650 method.

Claims (1)

As a method for preparing a phenol novolak resin by adding phenol, formaldehyde and an acid catalyst to the reaction tank, reacting the reaction product at a constant temperature for a certain time under stirring, and removing the produced water, unreacted phenol and residual catalyst from the reaction product.
The reaction molar ratio (P / F molar ratio) of the said phenol and an aldehyde is 3-6 mol, More preferably, it is 4-5 mol. The manufacturing method of the phenol novolak resin characterized by the above-mentioned.

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