JPS60199014A - Production of tung oil-modified phenolic resin - Google Patents

Abstract

PURPOSE:To produce the titled resin having high trasparency without lowering electrical properties and plasticity, by mixing a reaction product of a phenolic compound and tung oil with a reaction product of methyl eleostearate and a phenolic compound at a specific ratio, and reacting the mixture with formaldehyde. CONSTITUTION:The reaction product (TP) prepared by the reaction of a phenolic compound with tung oil in the presence of p-toluene-sulfonic acid, triethanolamine, etc. is mixed with the reaction product (EP) prepared by the reacton of methyl eleostearate with a phenolic compound, at a weight ratio [EP/(TP+EP)] of 30-60. The mixture is made to react with formaldehyde in the presence of ammonia water, triethylamine, etc. to obtain the objective resin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention belongs to the field of phenolic resin plasticization technology. On the other hand, it also belongs to the field of manufacturing technology for laminates. More specifically, it belongs to the technical field of plasticizing phenolic resin laminates by modifying them with tung oil.

[Background Art] When producing a plasticized phenolic resin laminate, it is common practice to modify the resin with tung oil.

When reacting tung oil with phenols, it is a common practice to add water in order to make the addition reaction proceed stably.

If water is added, hydrolysis of tung oil by water will occur,
If a large amount of hydrolysis products (which are thought to be mainly carboxylic acids) are present, the electrical properties and punching processability of the resulting laminate will deteriorate. In order to avoid this, it is desirable to keep the amount of hydrolysis products below 5%.

Note that the percentage of hydrolyzate here is calculated as the ratio of the volume of substances with lower molecular weight than tung oil to the volume of the product produced by the addition reaction between tung oil and phenols, excluding unreacted phenols. This value is calculated using data from GPC measurements.

However, when the hydrolysis products are reduced, the resulting cured resin becomes opaque. If the resin becomes opaque, the performance or appearance of the laminate will deteriorate and the commercial value will decrease, which is undesirable. This is due to poor compatibility with the chemical properties), and as a result of poor compatibility, various performances deteriorate. It is difficult to improve transparency while reducing hydrolysis products as described above, and there has been a desire for a solution to this problem.

[Objective of the invention] To provide a method for producing a tung oil-modified phenolic resin with good transparency without deteriorating electrical performance and plasticity (evaluated by punching workability). With the goal.

[Disclosure of invention] Tung oil modification of phenolic resin has already been put into practical use.

The modification is characterized in that phenols and tung oil are first subjected to an addition reaction in the presence of a strong acid, and the addition reaction product is used as a modifier. That is, the content is that the addition reaction product, unreacted phenols (phenols may be added depending on the case), and formaldehyde are subjected to a condensation reaction in the presence of an alkali catalyst. As the phenols for the addition reaction with tung oil, there are used phenols such as phenol and cresol which are usually used as raw materials for producing phenolic resins and which have the property of undergoing an addition reaction with tung oil. In this case, phenols with vacant positions are said to have excellent reactivity.

Now, in this invention, when producing a tung oil-modified phenolic resin, a product (TP) obtained by reacting phenols and tung oil, and a product (TP) obtained by reacting eleostearic acid methyl ester and phenols. EP)
are blended in a weight ratio of EP/(TP+EP) in the range of 30 to 60, and this is reacted with formaldehyde.

In addition, in the above, the reaction between phenols and tung oil or eleostearic acid methyl ester is mainly a reaction called an addition reaction. contains unreacted phenols.

This will be explained in detail below.

[11 Reaction between tung oil and phenols Tung oil, phenols, a catalyst (strong acid such as para-toluenesulfonic acid), and water are heated in a reaction vessel with stirring to obtain an addition reaction product (referred to as TP). In this addition reaction, the amount of the hydrolysis product is 5% by weight or less (hereinafter abbreviated as %).

Note that the amount of hydrolyzed products decreases as the amount of water added at this time is reduced. However, too little water causes gelation, so a certain amount of water is necessary. The conditions for the addition reaction are not limited.

Although the weight ratio of tung oil/phenols in the above addition reaction is not intended to be limited, it is preferably in the range of 377 to 7/3, and the preferable amount of water added is 0.2 to 2.0% relative to the entire reaction system. In a 5% equivalent amount, para-toluenesulfonic acid is 0.2 to 1.0 in a 50% aqueous solution to the entire reaction system.
% equivalent amount is preferred. The reaction time is preferably 30 to 250 minutes, and the reaction temperature is preferably 70 to 90°C.

Triethanolamine is added after the reaction is complete. Preferably, this is added as an aqueous solution. The amount added is preferably 0.2 to 0.8% equivalent in terms of 50% aqueous solution based on the entire reaction system.

[11] Reaction between methyl eleostearate and phenols The tung oil in [I] above is replaced with methyl eleostearate and the reaction is carried out under the same conditions to obtain an addition reaction product (referred to as EP). However, it is not always necessary to add water.

[11 Preparation of modifier Weight ratio of the addition reaction (TP) obtained in [11] and the addition reaction (B P) obtained in [+1]: EP/ (TP+EP)
Mix so that the ratio is 30 to 70.

[IV] Production of tung oil modified phenolic resin Formalin and a catalyst are added to the modifier obtained above to obtain a modified phenolic resin. Although the reaction conditions are not limited, the reaction is usually carried out under the following conditions. That is, formaldehyde, usually formalin, is added so that the reaction molar ratio of formaldehyde/unreacted phenols is 1.0 to 1.5.

A catalyst is added to carry out a condensation reaction to obtain a modified phenol resin. The catalyst used here is, for example, ammonia, diethylamine, trimethylamine, or a mixture thereof. The reaction temperature is 60-11
Preferably, the temperature is 0°C and the reaction time is 40 to 240 minutes.

After the reaction, the mixture is dehydrated under reduced pressure and diluted by adding a solvent. Solvents used here include acetone, methanol, T
HF etc. are used.

The tung oil-modified phenolic resin obtained above is not particularly limited in its uses, but is particularly conveniently used for laminated boards. When a laminate is manufactured using this modified resin, it contains less carboxylic acid component, which is a hydrolysis product, and has excellent electrical performance and excellent plasticity as evaluated by punching workability. This makes it possible to produce laminates with different laminates.

Transparency is also good. The reason for this good transparency is not clear, but it is thought to be because the addition reaction product of methyl eleostearate and phenols has excellent compatibility with both the reactant of tung oil and the phenol resin. It will be done.

Example (1) A reaction between tung oil and phenols was carried out under the following conditions.

Phenol 61.4 parts by weight Tung oil 38.6 parts by weight Para-toluenesulfonic acid 0.7 parts by weight Water 1.3 parts by weight Triethanolamine (after reaction) 0.6 parts by weight Reaction temperature 80°C Reaction time 60 minutes or more The hydrolysis product in the obtained addition reaction product is 4
．． It was 5%.

Note that the hydrolyzate was measured by analysis using GPC. The amount of the hydrolyzed product was calculated as the ratio of the volume of tung oil molecules to the volume of the reaction product between tung oil and phenols, excluding unreacted phenols.

(2) Next, methyl eleostearate and phenol were reacted as follows.

Phenol 61.4 parts by weight Eleostearic acid methyl ester 38.6 parts by weight Para-toluenesulfonic acid 0. 7 parts by weight Triethanolamine (reaction t&) 0.6 parts by weight Reaction temperature 80°C Reaction time 60 minutes 30.4 in weight%
(0.50%, 60.70%), and a modified phenolic resin was synthesized using the following basic formulation.

TP, BP mixture 74.4 parts by weight Formalin (37%) 1.0 parts by weight 25% aqueous ammonia 1.0 parts by weight Triethylamine 2.4 parts by weight The reaction time was 150 minutes, and the reaction temperature was 80°C. After the reaction, the mixture was dehydrated under reduced pressure. For 100 parts by weight of the obtained resin, 4
A 0M part of methanol was added to obtain a varnish.

(4) In order to evaluate the performance of the tung oil-modified phenolic resin obtained above, a paper-based phenolic resin laminate was manufactured. That is, kraft paper with a thickness of 10 mils was impregnated with the above varnish, dried to prepare a prepreg, 8 sheets of prepreg were stacked, copper foil with adhesive was placed on top, and a laminate was obtained by pressure forming. Ta.

When the performance of the obtained laminate was examined, it was as shown in Table 1.

Comparative Example A comparative experiment was conducted under the same conditions as in the example. The results of the performance evaluation are shown in Table 2.

However, TP in Comparative Example 5 was conducted under the following reaction conditions.

Phenol 61.4 parts Tung oil 38.6 parts Para-toluenesulfonic acid 0.7 parts Water 4.31 parts Triethanolamine (after reaction) 0.6 parts Reaction temperature 80°C Reaction time 120 minutes Margin below E ] Table 1 Table 2 Note 2 Insulation resistance after boiling Performance at future surface temperature 50 [Effects of the invention] This invention provides a method for producing a tung oil-modified phenolic resin.
Addition reaction product of phenols and tung oil (TP), and addition reaction product of eleostearic acid methyl ester and phenol (TP).
EP), the weight ratio of EP/(TP+EP) is 30 to 60
Since it is characterized in that it is used as a modifier in a proportion within the range of , it was possible to obtain a modified phenol resin with excellent electrical properties and transparency.

Patent applicant: Matsushita Electric Works Co., Ltd. Representative Patent Attorney Toshimaru Takemoto (and 2 others)

Claims (1)

[Claims] (1) In the method for producing tung oil-modified phenolic resin, a product obtained by reacting phenols with tung oil (TP) and a product obtained by reacting eleostearic acid methyl ester with phenols (EP) are converted into BP. / (TP
+BP) in a weight ratio of 30 to 60, and reacting the mixture with formaldehyde.