JP2011068760A5 - - Google Patents

Description

The present invention relates to a method for co-production of high purity bisphenol F and a novolac type phenol resin excellent in balance of physical properties such as handling and heat resistance.

However, in the method disclosed in Patent Document 1, although high purity bisphenol F such as 99.6 % by weight is obtained, the obtained bisphenol type novolak resin has high viscosity and is insufficient in fluidity and impregnation. In addition, heat resistance is not sufficient.

An object of the present invention is to provide a production method capable of co-producing a high-purity bisphenol F and a bisphenol-type novolak resin having excellent handling such as fluidity and impregnation properties and excellent heat resistance.

Examples of formaldehyde include formalin, paraformaldehyde, and trioxane . Among them, formalin is preferable, and a formalin aqueous solution having a concentration of up to 42% by weight can be used, and a formalin aqueous solution having a concentration of 37 to 42% by weight is more preferable. Formaldehyde may be used alone or in combination of two or more.

The acid catalyst used in step 1 in the first step of the present invention may be a fixed bed of a solid acid catalyst such as a cation exchange resin, hydrochloric acid, sulfuric acid, salicylic acid, paratoluenesulfonic acid, oxalic acid Organic acids and inorganic acids such as these may be used. The reaction temperature and reaction time vary depending on the type and amount of the catalyst used or the reaction molar ratio [(P) / (F)], etc., but the reaction temperature is usually 50 to 110 ° C. The reaction time is usually 0.5 to 10 hours. After obtaining the mixture (1) in the first step, the catalyst can be decomposed and the produced water removed as necessary. While the decomposition and removal of product water of the catalyst, for example, a mixture obtained after completion of the reaction (1) can be performed by maintaining for 1-5 hours at 170 to 200 ° C., maintaining the temperature as needed You may perform pressure reduction of 200 mmHg or less.

The temperature of the thin film heat transfer medium when performing thin film distillation is preferably 150 to 200 ° C. so that the volatility of phenol and the phenol resin are difficult to decompose, and more preferably 170 to 190 ° C. In addition, it is preferable that the distiller outlet pressure is maintained at 10 to 50 mm Hg in the thin film distiller from the viewpoint of good phenol volatility, and a thin film distiller maintained at 20 to 40 mm Hg is more preferable. Further, when the mixture (1) is supplied to the thin film still, it is efficiently volatilized (removed) that phenol is supplied at a rate of 100 to 400 kg / hr per 1 m ² of the thin film transfer surface of the thin film still. It is preferable because it can be performed, and 200 to 320 kg / hr is more preferable.

Although the reason why the novolac type phenol resin obtained in the present invention is a novolac type phenol resin that is excellent in handling and excellent in heat resistance of the cured product is not clear, the inventors of the present invention are This is considered to be due to the content of tetranuclear and binuclear (bisphenol F) contained in (area% of GPC analysis chart) and the area ratio of the tetranuclear and binuclear. That is, in the present invention, by including the first step to the third step, the area percentage of the tetranuclear in the resulting novolak type phenol resin is 9 to 25%, and the area percentage of the binuclear is 4 to 4. 20% Ratio of tetranuclear area% (4) to dinuclear area% (2) [(4) / (2) is 0.4 to 2.5, The present inventors consider that the balance of the tetranuclear body has a great influence on the performance of the novolac type phenol resin.

In the third step, the thin-film surface heat transfer medium temperature is preferably 200 to 250 ° C. because distillation efficiency is good and decomposition of the novolac type phenol resin can be avoided, and 205 to 240 ° C. is more preferable. The thin film outlet pressure is preferably from 0.1 to 3 mmHg because distillation efficiency is good and a distillate with good quality is also obtained, and 0.2 to 2 mmHg is more preferable. Further, in the third step, the mixture (2) is supplied to the thin film distiller so that the mixture is 8 to ²⁰ g / hr per 1 cm ² of the transmission surface of the thin film because a distillate with good quality can be obtained. Preferably, 10-18 g / hr is more preferable.

<Evaluation of ease of handling>
A stirrer, thermocouple, and 255 g of novolak type phenol resin and 500 g of Epicron N-665-EXP-S [o-cresol novolak type epoxy resin, epoxy equivalent 202 g / eq, softening point 72 ° C., manufactured by DIC Corporation] Then, the mixture was charged into a stainless steel flask having a reflux condenser and a nitrogen introduction tube, melted and mixed at 120 ° C. in a nitrogen atmosphere, and the time for complete homogeneous melting was measured. The shorter the time, because the mixing time can be shortened, workability on obtaining industrially molded product, easy to handle. As a comparison, a phenol resin PHENOLITE TD-2131 [softening point: 80 ° C., manufactured by DIC Corporation] manufactured by a known method was used.